From 211d6710f65da75f97ff46df8ac070b27780cb0b Mon Sep 17 00:00:00 2001
From: kkapsner <github@mail.kkapsner.de>
Date: Tue, 26 Jan 2021 13:47:59 +0100
Subject: [PATCH] First proxy attempt

---
 lib/extension.js         | 10 +++++++++
 lib/iframeProtection.js  |  3 ++-
 lib/intercept.js         | 47 +++++++++++++++++++++++++++-------------
 lib/modifiedCanvasAPI.js |  3 ++-
 4 files changed, 46 insertions(+), 17 deletions(-)

diff --git a/lib/extension.js b/lib/extension.js
index 7d8a6e2..c61c166 100644
--- a/lib/extension.js
+++ b/lib/extension.js
@@ -136,6 +136,16 @@
 		}
 	};
 	
+	scope.createProxyFunction = function createProxyFunction(window, original, replacement){
+		const wrappedWindow = scope.getWrapped(window);
+		const handler = wrappedWindow.Object.create(wrappedWindow.Object);
+		handler.apply = scope.exportFunctionWithName(function(target, thisArgs, args){
+			// console.log(target, thisArgs, args);
+			return replacement.apply(thisArgs, args);
+		}, window, "");
+		return new wrappedWindow.Proxy(original, handler);
+	};
+	
 	const changedPropertiesByWindow = new WeakMap();
 	scope.changeProperty = function(window, group, {object, name, type, changed}){
 		let changedProperties = changedPropertiesByWindow.get(scope.getWrapped(window));
diff --git a/lib/iframeProtection.js b/lib/iframeProtection.js
index 42cf545..38461ab 100644
--- a/lib/iframeProtection.js
+++ b/lib/iframeProtection.js
@@ -25,7 +25,8 @@
 			const descriptor = Object.getOwnPropertyDescriptor(object, name);
 			const original = descriptor[type];
 			if ((typeof changed) === "function"){
-				changed = extension.exportFunctionWithName(changed, window, original.name);
+				// changed = extension.exportFunctionWithName(changed, window, original.name);
+				changed = extension.createProxyFunction(window, original, changed);
 			}
 			extension.changeProperty(window, "iframeProtection", {object, name, type, changed});
 		}
diff --git a/lib/intercept.js b/lib/intercept.js
index 8db72bc..ed77f03 100644
--- a/lib/intercept.js
+++ b/lib/intercept.js
@@ -240,7 +240,7 @@
 		name, changedFunction, siteStatus, original,
 		window: windowToProcess, prefs, notify, checkStack, ask
 	}){
-		return function checker(callingDepth = 2){
+		return function checker(callingDepth = 3){
 			const errorStack = (new Error()).stack;
 			
 			try {
@@ -344,24 +344,39 @@
 				let changed;
 				if (type ==="value"){
 					if (changedFunction.fakeGenerator){
-						changed = extension.exportFunctionWithName(
-							changedFunction.fakeGenerator(checker, original, windowToProcess),
-							windowToProcess,
-							original.name
-						);
+						// const proxy = new windowToProcess.Proxy(original, {apply: function(target, thisArgs, args){
+						// 	console.log(target, thisArgs, args, generated);
+						// 	return generated.apply(thisArgs, args);
+						// }});
+						if ((changedFunction.exportOptions || {}).allowCallbacks){
+							changed = extension.exportFunctionWithName(
+								changedFunction.fakeGenerator(checker, original, windowToProcess),
+								windowToProcess,
+								original.name
+							);
+						}
+						else {
+							const generated = changedFunction.fakeGenerator(checker, original, windowToProcess);
+							changed = extension.createProxyFunction(windowToProcess, original, generated);
+						}
 					}
 					else {
 						changed = null;
 					}
 				}
 				else {
-					changed = extension.exportFunctionWithName(function(){
-						return extension.exportFunctionWithName(
-							changedFunction.fakeGenerator(checker),
-							windowToProcess,
-							original.name
-						);
-					}, windowToProcess, descriptor.get.name);
+					// changed = extension.exportFunctionWithName(function(){
+					// 	return extension.exportFunctionWithName(
+					// 		changedFunction.fakeGenerator(checker),
+					// 		windowToProcess,
+					// 		original.name
+					// 	);
+					// }, windowToProcess, descriptor.get.name);
+					changed = extension.createProxyFunction(windowToProcess, original, extension.exportFunctionWithName(
+						changedFunction.fakeGenerator(checker),
+						windowToProcess,
+						original.name
+					));
 				}
 				extension.changeProperty(windowToProcess, changedFunction.api, {
 					object, name, type, changed
@@ -393,7 +408,8 @@
 					extension.changeProperty(windowToProcess, changedGetter.api,
 						{
 							object, name, type: "get",
-							changed: extension.exportFunctionWithName(getter, windowToProcess, original.name)
+							// changed: extension.exportFunctionWithName(getter, windowToProcess, original.name)
+							changed: extension.createProxyFunction(windowToProcess, original, getter)
 						}
 					);
 					
@@ -407,7 +423,8 @@
 						extension.changeProperty(windowToProcess, changedGetter.api,
 							{
 								object, name, type: "set",
-								changed: extension.exportFunctionWithName(setter, windowToProcess, original.name)
+								// changed: extension.exportFunctionWithName(setter, windowToProcess, original.name)
+								changed: extension.createProxyFunction(windowToProcess, original, setter)
 							}
 						);
 					}
diff --git a/lib/modifiedCanvasAPI.js b/lib/modifiedCanvasAPI.js
index 4935345..42797af 100644
--- a/lib/modifiedCanvasAPI.js
+++ b/lib/modifiedCanvasAPI.js
@@ -372,7 +372,8 @@
 				return function mozGetAsFile(callback){
 					return checkerWrapper(checker, this, arguments, useFakeCanvasCallback);
 				};
-			}
+			},
+			exportOptions: {allowCallbacks: true}
 		},
 		getImageData: {
 			type: "readout",