Redirect/universal_redirect.js

// entry point
function main(stage, parameters) {
	if (!parameters.redirectHost) {
		console.log("redirectHost parameter not specified!\nEdit your gadget.config and specify redirectHost in \"parameters\" section.");
		return;
	}
	
	// Redirect http requests
	const UnityWebRequestSetUrlPtr = Helpers.FindMethodImpl("UnityEngine.UnityWebRequestModule.dll", "UnityEngine.Networking", "UnityWebRequest", "set_url", 1);
	const UriCtorPtr = Helpers.FindMethodImpl("System.dll", "System", "Uri", ".ctor", 1);
	
	console.log("Found UnityWebRequest::set_url at " + UnityWebRequestSetUrlPtr);
	console.log("Found Uri::ctor at " + UriCtorPtr);
	
	RedirectCallback.targetHost = parameters.redirectHost;
	Interceptor.attach(UnityWebRequestSetUrlPtr, RedirectCallback);
	Interceptor.attach(UriCtorPtr, RedirectCallback);

	console.log("Attached successfully, will redirect all requests to: " + parameters.redirectHost);
	
	// Hook ZFGameBrowser to redirect in-game WebView
	const BrowserLoadURL = Helpers.FindMethodImpl("ZFBrowser.dll", "ZenFulcrum.EmbeddedBrowser", "Browser", "LoadURL", 2);
	
	if (BrowserLoadURL) {
		Interceptor.attach(BrowserLoadURL, {
			onEnter(args) {
				var requestUrl = args[1].readCSharpString();
				var prefix = requestUrl.split('/', 3).join('/');
				args[1] = Il2cppApiWrap.AllocateString(requestUrl.replace(prefix, parameters.redirectHost));
				
				console.log("EmbeddedBrowser redirected: " + args[1].readCSharpString());
			}
		});
		
		console.log("Successfully hooked EmbeddedBrowser");
	}
}

const RedirectCallback = {
	onEnter(args) {
		var requestUrl = args[1].readCSharpString();
		if (requestUrl.startsWith("http://") || requestUrl.startsWith("https://")) {
			if (requestUrl.includes(RedirectCallback.targetHost)) return; // already redirected
			
			var prefix = requestUrl.split('/', 3).join('/');
			args[1] = Il2cppApiWrap.AllocateString(requestUrl.replace(prefix, RedirectCallback.targetHost));
			
			console.log("redirected: " + args[1].readCSharpString());
		}
	}
};

const Helpers = {
	FindMethodImpl(moduleName, namespace, className, methodName, argCount) {
		const module = Il2cppApiWrap.GetImageByName(moduleName);
		if (module.equals(ptr(0))) return null;
		
		const il2cppClass = Il2cppApiWrap.GetClassByName(module, namespace, className);
		if (il2cppClass.equals(ptr(0))) return null;
		
		const il2cppMethod = Il2cppApiWrap.GetClassMethodByName(il2cppClass, methodName, argCount);
		if (il2cppMethod.equals(ptr(0))) return null;
		
		return il2cppMethod.readPointer();
	}
}

const Il2cppApiWrap = {
	AllocateString(value) {
		const pValue = Memory.allocUtf16String(value);
		
		return this.CallApiFunction('il2cpp_string_new_utf16', 'pointer', ['pointer', 'int'], [pValue, value.length]);
	},
	GetClassMethodByName(il2cppClass, name, argsCount) {
		const pName = Memory.allocUtf8String(name);
		
		return this.CallApiFunction('il2cpp_class_get_method_from_name', 'pointer', ['pointer', 'pointer', 'int'], [il2cppClass, pName, argsCount]);
	},
	GetClassByName(il2cppImage, namespace, name) {
		const pNamespace = Memory.allocUtf8String(namespace);
		const pName = Memory.allocUtf8String(name);
		
		return this.CallApiFunction('il2cpp_class_from_name', 'pointer', ['pointer', 'pointer', 'pointer'], [il2cppImage, pNamespace, pName]);
	},
	GetImageByName(name) {
		const domain = this.CallApiFunction('il2cpp_domain_get', 'pointer', [], []);
		
		const sizeOut = Memory.alloc(8);
		const assemblies = this.CallApiFunction('il2cpp_domain_get_assemblies', 'pointer', ['pointer', 'pointer'], [domain, sizeOut]);
		
		const size = sizeOut.readU64();
		for (var i = 0; i < size; i++) {
			const assembly = assemblies.add(i * 8).readPointer();
			const il2cppImage = this.CallApiFunction('il2cpp_assembly_get_image', 'pointer', ['pointer'], [assembly]);
			
			const imageName = this.CallApiFunction('il2cpp_image_get_name', 'pointer', ['pointer'], [il2cppImage]);
			if (imageName.readUtf8String() == name) {
				return il2cppImage;
			}
		}
		
		return null;
	},
	CallApiFunction(name, rettype, argTypes, args) {
		const nativeFunction = new NativeFunction(Module.findExportByName(null, name), rettype, argTypes);
		return nativeFunction.apply(nativeFunction, args);
	}
}

NativePointer.prototype.readCSharpString = function() {
    var length = this.add(16).readInt();
    return this.add(20).readUtf16String(length);
}

rpc.exports.init = main;