Added preference to control rng type.

lib/askForPermission.js

@@ -14,7 +14,7 @@
 		if (context){
 			var nodeName;
 			try {
-				nodeName = context.nodeName
+				nodeName = context.nodeName;
 			}
 			catch (e){}
 			if (nodeName === "CANVAS"){

lib/callingStack.js

@@ -1,4 +1,4 @@
-/* global console,exports */
+/* global exports */
 /* jslint moz: true */
 /* 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

lib/intercept.js

@@ -5,10 +5,22 @@
 (function(){
 	"use strict";
 	
-	const {changedFunctions} = require("./modifiedAPI");
+	const {changedFunctions, setRandomSupply} = require("./modifiedAPI");
+	const randomSupplies = require("./randomSupplies");
+	setRandomSupply(randomSupplies.nonPersistent);
 	var apiNames = Object.keys(changedFunctions);
 	var undef;
 	
+	function setRandomSupplyByType(type){
+		switch (type){
+			case "persistent":
+				setRandomSupply(randomSupplies.persistent);
+				break;
+			default:
+				setRandomSupply(randomSupplies.nonPersistent);
+		}
+	}
+	exports.setRandomSupplyByType = setRandomSupplyByType;
 	exports.intercept = function intercept({subject: window}, {check, ask, notify, prefs}){
 		apiNames.forEach(function(name){
 			var changedFunction = changedFunctions[name];
@@ -34,8 +46,8 @@
 								case "allow":
 									return original;
 								case "fake":
+									setRandomSupplyByType(prefs("rng"));
 									if (changedFunction.fake){
-										
 										return changedFunction.fake;
 									}
 									else {

lib/modifiedAPI.js

@@ -1,20 +1,13 @@
-/* jslint moz: true, bitwise: true */
+/* jslint moz: true */
 /* 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";
 	
-	const rnd = {};
+	var randomSupply = null;
+	
 	function getFakeCanvas(window, original){
-		var domain = window.document.location.host;
-		if (!rnd[domain]){
-			rnd[domain] = new Uint8Array(128);
-			for (var i = 0; i < rnd[domain].length; i += 1){
-				rnd[domain][i] = Math.floor(Math.random() * 0xFF);
-			}
-			console.log("created new rnd for domain", domain);
-		}
 		var context = window.HTMLCanvasElement.prototype.getContext.call(original, "2d");
 		var imageData, data, source;
 		if (context){
@@ -38,14 +31,10 @@
 		}
 		data = imageData.data;
 		var l = data.length;
+		var rng = randomSupply.getRng(l, window);
 		
 		for (var i = 0; i < l; i += 1){
-			var value = source[i];
-			var index = value & 0x7F;
-			var bitIndex = ((i & 0x03) << 1) | (value >>> 7);
-			var bit = (rnd[domain][index] >>> bitIndex) & 0x01;
-			if (bitIndex % 2) console.log(rnd[domain][index], index, bitIndex, bit);
-			data[i] = value ^ bit;
+			data[i] = rng(source[i], i);
 		}
 		var canvas = original.cloneNode(true);
 		context = window.HTMLCanvasElement.prototype.getContext.call(canvas, "2d");
@@ -55,6 +44,10 @@
 	function getWindow(canvas){
 		return canvas.ownerDocument.defaultView;
 	}
+	
+	exports.setRandomSupply = function(supply){
+		randomSupply = supply;
+	};
 	// changed functions and their fakes
 	exports.changedFunctions = {
 		getContext: {
@@ -111,7 +104,7 @@
 						imageData.data[i] = data[i];
 					}
 					return imageData;
-				}
+				};
 			}
 		},
 		readPixels: {

lib/randomSupplies.js

@@ -0,0 +1,68 @@
+/* jslint moz: true, bitwise: true */
+/* 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";
+	
+	const persistentRnd = {};
+	exports.persistent = {
+		getRng: function(length, window){
+			var domain = window.document.location.host;
+			if (!persistentRnd[domain]){
+				persistentRnd[domain] = new Uint8Array(128);
+				for (var i = 0; i < persistentRnd[domain].length; i += 1){
+					persistentRnd[domain][i] = Math.floor(Math.random() * 0xFF);
+				}
+			}
+			var bitSet = persistentRnd[domain];
+			
+			return function(value, i){
+				var index = value & 0x7F;
+				var bitIndex = ((i & 0x03) << 1) | (value >>> 7);
+				var bit = (bitSet[index] >>> bitIndex) & 0x01;
+				return value ^ bit;
+			};
+		}
+	};
+	
+	exports.nonPersistent = {
+		getRng: function(length, window){
+			var randomI = 65536;
+			// var randomOffset = 0;
+			var randomNumbers = new Uint8Array(Math.min(65536, length));
+			
+			return function(value, i){
+				if (randomI >= randomNumbers.length){
+					randomI = 0;
+					// randomOffset += randomNumbers.length;
+					if (length - i < 65536){
+						randomNumbers = new Uint8Array(length - i);
+					}
+					window.crypto.getRandomValues(randomNumbers);
+				}
+				var rnd = randomNumbers[randomI];
+				if (value >= 0x80){
+					value = value ^ (rnd & 0x1F);
+				}
+				else if (value >= 0x40){
+					value = value ^ (rnd & 0x0F);
+				}
+				else if (value >= 0x20){
+					value = value ^ (rnd & 0x07);
+				}
+				else if (value >= 0x10){
+					value = value ^ (rnd & 0x03);
+				}
+				else if (value >= 0x08){
+					value = value ^ (rnd & 0x01);
+				}
+				// else if (value >= 0x04){
+					// value = value ^ (rnd * 0x00);
+				// }
+				randomI += 1;
+				return value;
+			};
+		}
+	};
+}());	

locale/de-DE.json

@@ -11,6 +11,7 @@
 	"askOnlyOnce_title": "Nur einmal nachfragen",
 	"blackList_description": "Domänen oder URLs, die die <canvas>-API niemals verwenden dürfen. Mehrere Einträge müssen durch ein Komma getrennt werden.",
 	"blackList_title": "Blacklist",
+	
 	"blockMode_description": "",
 	"blockMode_options.allow everything": "alles erlauben",
 	"blockMode_options.allow only white list": "nur Einträge der Whitelist erlauben",
@@ -21,13 +22,21 @@
 	"blockMode_options.block readout API": "Auslese-API blockieren",
 	"blockMode_options.fake readout API": "Auslese-API vortäuschen",
 	"blockMode_title": "Blockiermodus",
- "maxFakeSize_description": "Maximale Vortäuschgröße", 
- "maxFakeSize_": "Canvas, die eine größe Fläche als die hier angegeben Zahl haben, werden nicht vorgetäuscht. (Null eingeben, um es zu deaktivieren.)", 
+	
+	"maxFakeSize_description": "Canvas, die eine größe Fläche als die hier angegeben Zahl haben, werden nicht vorgetäuscht. (Null eingeben, um es zu deaktivieren.)",
+	"maxFakeSize_title": "Maximale Vortäuschgröße",
+	
+	"rng_description": "",
+	"rng_options.persistent": "persistent",
+	"rng_options.non persistent": "nicht persistent",
+	"rng_title": "Zufallszahlengenerator",
+	
 	"disableNotifications": "Benachrichtigungen deaktivieren",
 	"displayCallingStack": "Aufrufestack anzeigen",
 	"displayFullURL": "URL anzeigen",
 	"enableStackList_description": "",
 	"enableStackList_title": "Dateispezifische Whitelist verwenden",
+	
 	"fakedReadout": "Auslese vorgetäuscht auf {url}",
 	"ignoreList_description": "Domänen oder URLs, bei denen keine Benachrichtigung angezeigt werden. Mehrere Einträge müssen durch ein Komma getrennt werden.",
 	"ignoreList_title": "Ignorierliste",

locale/en-US.json

@@ -11,6 +11,7 @@
 	"askOnlyOnce_title": "Ask only once",
 	"blackList_description": "Domains or URLs where the <canvas>-API should always be blocked. To add multiple entries, separate them by commas.",
 	"blackList_title": "Black list",
+	
 	"blockMode_description": "",
 	"blockMode_options.allow everything": "allow everything",
 	"blockMode_options.allow only white list": "allow only white list",
@@ -21,13 +22,21 @@
 	"blockMode_options.block readout API": "block readout API",
 	"blockMode_options.fake readout API": "fake readout API",
 	"blockMode_title": "Block mode",
- "maxFakeSize_description": "Maximal fake size", 
- "maxFakeSize_": "Canvas with a bigger area than this number will not be faked. (Enter zero to disable.)", 
+	
+	"maxFakeSize_description": "Canvas with a bigger area than this number will not be faked. (Enter zero to disable.)",
+	"maxFakeSize_title": "Maximal fake size",
+	
+	"rng_description": "",
+	"rng_options.persistent": "persistent",
+	"rng.non persistent": "non persistent",
+	"rng_title": "Random number generator",
+
 	"disableNotifications": "disable notifications",
 	"displayCallingStack": "display calling stack",
 	"displayFullURL": "display full URL",
 	"enableStackList_description": "",
 	"enableStackList_title": "Use file specific white list",
+	
 	"fakedReadout": "Faked readout on {url}",
 	"ignoreList_description": "Domains or URLs where no notification will be shown. To add multiple entries, separate them by commas.",
 	"ignoreList_title": "Ignore list",

package.json

@@ -68,6 +68,22 @@
 			"type": "integer",
 			"value": 0
 		},
+		{
+			"name": "rng",
+			"title": "Random number generator",
+			"type": "menulist",
+			"value": "nonPersistent",
+			"options": [
+				{
+					"value": "nonPersistent",
+					"label": "non persistent"
+				},
+				{
+					"value": "persistent",
+					"label": "persistent"
+				}
+			]
+		},
 		{
 			"name": "askOnlyOnce",
 			"title": "Ask only once",