Added askReadout

data/inject.js

@@ -1,4 +1,4 @@
-/* global self, window, console, unsafeWindow */
+/* global self, window, console, unsafeWindow, exportFunction */
 (function(){
 	"use strict";
 	
@@ -12,7 +12,12 @@
 			}
 		},
 		readAPI: {
-			status: "allow"
+			status: "allow",
+			askStatus: {
+				askOnce: false,
+				alreadyAsked: false,
+				answer: null
+			}
 		}
 	};
 	
@@ -62,108 +67,86 @@
 		return bytes;
 	}());
 	
-	var originalToDataURL = unsafeWindow.HTMLCanvasElement.prototype.toDataURL;
+	// Readout API blocking
-	Object.defineProperty(
+	var fakeFunctions = {
-		unsafeWindow.HTMLCanvasElement.prototype,
+		toDataURL: {
-		"toDataURL",
+			object: unsafeWindow.HTMLCanvasElement,
-		{
+			func: function(){
-			enumerable: true,
+				var type = arguments[0] || "image/png";
-			configureable: false,
+				return "data:" + type + ";base64," + btoa(randomImage);
-			get: exportFunction(function(){
+			}
-				switch (blockMode.readAPI.status){
+		},
-					case "allow":
+		toBlob: {
-						return originalToDataURL;
+			object: unsafeWindow.HTMLCanvasElement,
-					case "block":
+			func: function(callback){
-					default:
+				var type = arguments[0] || "image/png";
-						return exportFunction(
+				var blob = new window.Blob(randomImage, {type: type});
-							function(){
+				callback(blob);
-								var type = arguments[0] || "image/png";
+			},
-								return "data:" + type + ";base64," + btoa(randomImage);
+			exportOptions: {allowCallbacks: true}
-							},
+		},
-							unsafeWindow
+		mozGetAsFile: {
-						);
+			object: unsafeWindow.HTMLCanvasElement,
+			func: undef
+		},
+		getImageData: {
+			object: unsafeWindow.CanvasRenderingContext2D,
+			func: function(sx, sy, sw, sh){
+				var imageData = new window.ImageData(sw, sh);
+				var l = sw * sh * 4;
+				for (var i = 0; i < l; i += 1){
+					imageData.data[i] = Math.floor(
+						Math.random() * 256
+					);
 				}
-			}, unsafeWindow)
+				return imageData;
+			}
 		}
-	);
+	};
 	
-	var originalToBlob = unsafeWindow.HTMLCanvasElement.prototype.toBlob;
+	Object.keys(fakeFunctions).forEach(function(name){
-	Object.defineProperty(
+		var fakeFunction = fakeFunctions[name];
-		unsafeWindow.HTMLCanvasElement.prototype,
+		var original = fakeFunction.object.prototype[name];
-		"toBlob",
+		Object.defineProperty(
-		{
+			fakeFunction.object.prototype,
-			enumerable: true,
+			name,
-			configureable: false,
+			{
-			get: exportFunction(function(){
+				enumerable: true,
-				switch (blockMode.readAPI.status){
+				configureable: false,
-					case "allow":
+				get: exportFunction(function(){
-						return originalToBlob;
+					var status = blockMode.readAPI.status;
-					case "block":
+					if (status === "ask"){
-					default:
+						var askStatus = blockMode.readAPI.askStatus;
-						return exportFunction(
+						var allow;
-							function(callback){
+						if (askStatus.askOnce && askStatus.alreadyAsked){
-								var type = arguments[0] || "image/png";
+							// console.log("already asked");
-								var blob = new window.Blob(randomImage, {type: type});
+							allow = askStatus.answer;
-								callback(blob);
+						}
-							},
+						else {
-							unsafeWindow,
+							// console.log("asking");
-							{allowCallbacks: true}
+							allow = window.confirm(_("askForReadoutPermission"));
-						);
+							askStatus.alreadyAsked = true;
-				}
+							askStatus.answer = allow;
-			}, unsafeWindow)
+						}
-		}
+						status = allow? "allow": "block";
-	);
+					}
+					switch (status){
+						case "allow":
+							return original;
+						case "block":
+						default:
+							return exportFunction(
+								fakeFunction.func,
+								unsafeWindow,
+								fakeFunction.exportOptions
+							);
+					}
+				}, unsafeWindow)
+			}
+		);
+	});
 	
-	var originalMozGetAsFile = unsafeWindow.HTMLCanvasElement.prototype.mozGetAsFile;
+	// Translation
-	Object.defineProperty(
-		unsafeWindow.HTMLCanvasElement.prototype,
-		"mozGetAsFile",
-		{
-			enumerable: true,
-			configureable: false,
-			get: exportFunction(function(){
-				switch (blockMode.readAPI.status){
-					case "allow":
-						return originalMozGetAsFile;
-					case "block":
-					default:
-						undef
-				}
-			}, unsafeWindow)
-		}
-	);
-	
-	var originalGetImageData = unsafeWindow.CanvasRenderingContext2D.prototype.getImageData;
-	Object.defineProperty(
-		unsafeWindow.CanvasRenderingContext2D.prototype,
-		"getImageData",
-		{
-			enumerable: true,
-			configureable: false,
-			get: exportFunction(function(){
-				switch (blockMode.readAPI.status){
-					case "allow":
-						return originalGetImageData;
-					case "block":
-					default:
-						return exportFunction(
-							function(sx, sy, sw, sh){
-								var imageData = new window.ImageData(sw, sh);
-								var l = sw * sh * 4;
-								for (var i = 0; i < l; i += 1){
-									imageData.data[i] = Math.floor(
-										Math.random() * 256
-									);
-								}
-								return imageData;
-							},
-							unsafeWindow
-						);
-				}
-			}, unsafeWindow)
-		}
-	);
-
 	var _ = function(name){
 		return _[name] || name;
 	};
@@ -171,6 +154,8 @@
 		_[name] = translation;
 	});
 	
+	// Communication with main.js
+	
 	function checkPDF(blocking){
 		if (document.contentType.match(/\/pdf$/i)){
 			self.port.emit("isPDF", blocking);
@@ -198,6 +183,13 @@
 			blockMode.readAPI.status = "block";
 		}
 	});
+	self.port.on("askReadout", function(force, askOnce){
+		if (force || !checkPDF("askReadout")){
+			blockMode.getContext.status = "allow";
+			blockMode.readAPI.status = "ask";
+			blockMode.readAPI.askStatus.askOnce = askOnce;
+		}
+	});
 	self.port.on("unblock", function(){
 		blockMode.getContext.status = "allow";
 		blockMode.readAPI.status = "allow";

lib/main.js

@@ -109,6 +109,17 @@
 					mode = "blockReadout";
 				}
 				break;
+			case "askReadout":
+				if (whiteList.match(url)){
+					mode = "unblock";
+				}
+				else if (blackList.match(url)){
+					mode = "block";
+				}
+				else {
+					mode = "askReadout";
+				}
+				break;
 			case "blockOnlyBlackList":
 				if (blackList.match(url)){
 					mode = "block";
@@ -161,6 +172,7 @@
 				}
 			});
 			worker.port.emit("setTranslation", "askForPermission", _("askForPermission"));
+			worker.port.emit("setTranslation", "askForReadoutPermission", _("askForReadoutPermission"));
 			checkWorker(worker);
 		},
 	});

locale/de-DE.properties

@@ -11,6 +11,7 @@ blockMode_options.block everything= alles blockieren
 blockMode_options.allow only white list= nur Einträge der Whitelist erlauben
 blockMode_options.ask for permission= um Erlaubnis fragen
 blockMode_options.block readout API= Auslese-API blockieren
+blockMode_options.ask for readout API permission= bei Auslese-API um Erlaubnis fragen
 blockMode_options.block only black list= nur Einträge der Blacklist blockieren
 blockMode_options.allow everything= alles erlauben
 
@@ -20,4 +21,5 @@ askOnlyOnce_description= Wenn eine Seite öfters versucht, die <canvas>-API abzu
 allowPDFCanvas_title= <canvas> in PDFs erlauben
 allowPDFCanvas_description= Die native pdf.js verwendet <canvas> um den Inhalt von PDFs anzuzeigen. Wenn dies nicht markiert ist, werden viele Nachfragedialoge erscheinen oder die PDF Ansicht nicht funktionieren.
 
-askForPermission= Wollen Sie <canvas> erlauben?
+askForPermission= Wollen Sie <canvas> erlauben?
+askForReadoutPermission= Wollen Sie das Auslesen von <canvas> erlauben?

locale/en-US.properties

@@ -11,6 +11,7 @@ blockMode_options.block everything= block everything
 blockMode_options.allow only white list= allow only white list
 blockMode_options.ask for permission= ask for permission
 blockMode_options.block readout API= block readout API
+blockMode_options.ask for readout API permission= ask for readout API permission
 blockMode_options.block only black list= block only black list
 blockMode_options.allow everything= allow everything
 
@@ -20,4 +21,5 @@ askOnlyOnce_description= If a page tries to access the <canvas>-API several time
 allowPDFCanvas_title= Allow canvas in PDFs
 allowPDFCanvas_description= The native pdf.js uses <canvas> to display the PDF content. If this is unchecked there will lots of annoying ask dialogs or the PDF display will not work.
 
-askForPermission= Do you want to allow <canvas>?
+askForPermission= Do you want to allow <canvas>?
+askForReadoutPermission= Do you want to allow <canvas> readout?

package.json

@@ -20,7 +20,7 @@
 			"name": "blockMode",
 			"title": "block mode",
 			"type": "menulist",
-			"value": "blockReadout",
+			"value": "askReadout",
 			"options": [
 				{
 					"value": "blockEverything",
@@ -38,6 +38,10 @@
 					"value": "blockReadout",
 					"label": "block readout API"
 				},
+				{
+					"value": "askReadout",
+					"label": "ask for readout API permission"
+				},
 				{
 					"value": "blockOnlyBlackList",
 					"label": "block only black list"