separate persistent random numbers for incognito windows

lib/frame.js

@@ -56,12 +56,14 @@
 			notice("my tab id is", data.tabId);
 			tabId = data.tabId;
 		}
-		if (data.hasOwnProperty("persistentRnd")){
+		const persistentRndName = "persistent" + (browser.extension.inIncognitoContext? "Incognito": "") + "Rnd";
-			notice("got persistent random data", data.persistentRnd);
+		if (data.hasOwnProperty(persistentRndName)){
+			const persistentRndValue = data[persistentRndName];
+			notice("got persistent random data", persistentRndValue);
 			const {persistent: persistentRnd} = require("./randomSupplies.js");
-			Object.keys(data.persistentRnd).forEach(function(domain){
+			Object.keys(persistentRndValue).forEach(function(domain){
-				verbose("random data for", domain, data.persistentRnd[domain]);
+				verbose("random data for", domain, persistentRndValue[domain]);
-				persistentRnd.setDomainRnd(domain, data.persistentRnd[domain]);
+				persistentRnd.setDomainRnd(domain, persistentRndValue[domain]);
 			});
 		}
 	});

lib/main.js

@@ -28,6 +28,7 @@
 			if (data["canvasBlocker-new-domain-rnd"]){
 				persistentRndStorage.setDomainData(
 					data["canvasBlocker-new-domain-rnd"].domain,
+					data["canvasBlocker-new-domain-rnd"].incognito,
 					data["canvasBlocker-new-domain-rnd"].rnd
 				);
 				if (keys.length === 1){
@@ -55,7 +56,8 @@
 			verbose("send back the persistent random seeds", persistentRndStorage.persistentRnd);
 			port.postMessage({
 				tabId: port.sender.tab.id,
-				persistentRnd: persistentRndStorage.persistentRnd
+				persistentRnd: persistentRndStorage.persistentRnd,
+				persistentIncognitoRnd: persistentRndStorage.persistentIncognitoRnd
 			});
 			var url = new URL(port.sender.url);
 			port.onMessage.addListener(function(data){

lib/persistentRndStorage.js

@@ -18,6 +18,7 @@
 	const logging = require("./logging");
 	
 	scope.persistentRnd = Object.create(null);
+	scope.persistentIncognitoRnd = Object.create(null);
 	scope.init = function init(){
 		logging.message("initializing persistent rng storage");
 
@@ -75,6 +76,16 @@
 		};
 	}();
 	
+	browser.windows.onRemoved.addListener(function(){
+		browser.windows.getAll().then(function(windows){
+			if (windows.every(function(window){
+				return !window.incognito;
+			})){
+				clearIncognito();
+			}
+		});
+	});
+
 	let clearTimeout;
 	function registerTimeout(){
 		var interval = getInterval();
@@ -98,19 +109,30 @@
 			});
 		});
 	}
+	function clearIncognito(){
+		scope.persistentIncognitoRnd = Object.create(null);
+		settings.persistentIncognitoRndStorage = JSON.stringify(scope.persistentIncognitoRnd);
+	}
 	function clear(){
 		logging.verbose("domain rnd cleared");
 		scope.persistentRnd = Object.create(null);
 		settings.persistentRndStorage = JSON.stringify(scope.persistentRnd);
 		settings.lastPersistentRndClearing = Date.now();
+		clearIncognito();
 		registerTimeout();
 		broadcast({"canvasBlocker-clear-domain-rnd": true});
 	}
-	function setDomainData(domain, rnd){
+	function setDomainData(domain, incognito, rnd){
-		logging.verbose("got new domain rnd for ", domain, ":", rnd);
+		logging.verbose("got new domain rnd for ", domain, " (incognito:", incognito, "):", rnd);
-		scope.persistentRnd[domain] = rnd;
+		if (incognito){
-		settings.persistentRndStorage = JSON.stringify(scope.persistentRnd);
+			scope.persistentIncognitoRnd[domain] = rnd;
-		broadcast({"canvasBlocker-set-domain-rnd": {domain, rnd}});
+			settings.persistentIncognitoRndStorage = JSON.stringify(scope.persistentIncognitoRnd);
+		}
+		else {
+			scope.persistentRnd[domain] = rnd;
+			settings.persistentRndStorage = JSON.stringify(scope.persistentRnd);
+		}
+		broadcast({"canvasBlocker-set-domain-rnd": {domain, incognito, rnd}});
 	}
 
 	scope.clear = clear;

lib/randomSupplies.js

@@ -80,7 +80,11 @@
 	var persistentRnd = Object.create(null);
 	settings.onloaded(function(){
 		try {
-			let storedData = JSON.parse(settings.persistentRndStorage);
+			let storedData = JSON.parse(
+				browser.extension.inIncognitoContext?
+					settings.persistentIncognitoRndStorage:
+					settings.persistentRndStorage
+			);
 			for (var domain in storedData){
 				var value = storedData[domain];
 				if (
@@ -102,8 +106,10 @@
 		
 		browser.runtime.onMessage.addListener(function(data){
 			if (data["canvasBlocker-set-domain-rnd"]){
-				var {domain, rnd} = data["canvasBlocker-set-domain-rnd"];
+				var {domain, incognito, rnd} = data["canvasBlocker-set-domain-rnd"];
-				persistentRnd[domain] = new Uint8Array(rnd);
+				if (incognito === browser.extension.inIncognitoContext){
+					persistentRnd[domain] = new Uint8Array(rnd);
+				}
 			}
 			if (data["canvasBlocker-clear-domain-rnd"]){
 				persistentRnd = Object.create(null);
@@ -117,7 +123,11 @@
 				persistentRnd[domain] = new Uint8Array(128);
 				window.crypto.getRandomValues(persistentRnd[domain]);
 				browser.runtime.sendMessage({
-					"canvasBlocker-new-domain-rnd": {domain, rnd: Array.from(persistentRnd[domain])}
+					"canvasBlocker-new-domain-rnd": {
+						domain,
+						incognito: browser.extension.inIncognitoContext,
+						rnd: Array.from(persistentRnd[domain])
+					}
 				});
 			}
 			return persistentRnd[domain];

lib/settingDefinitions.js

@@ -113,6 +113,11 @@
 			name: "persistentRndStorage",
 			defaultValue: ""
 		},
+		{
+			name: "persistentIncognitoRndStorage",
+			resetOnStartup: true,
+			defaultValue: ""
+		},
 		{
 			name: "storePersistentRnd",
 			defaultValue: false

releaseNotes.txt

@@ -3,11 +3,13 @@ Version 0.5.2:
 		- 
 	
 	new features:
-		- 
+		- separate persistent random numbers for incognito windows
+			(resets when closing all incognito windows - like cookies do)
 	
 	fixes:
 		- optimized CSP
 		- in Firefox ESR (52) iFrames with a blob-URL cannot be protected -> they have to be blocked there as well
+		- broken when using with Random Agent Spoofer
 	
 	known issues:
 		- if a data URL is blocked the page action button does not appear