utils of hook javascript function and value changes for js reverse engineering
As of
// ==UserScript==
// @name ConsoleHook
// @namespace http://tampermonkey.net/
// @version 2025-01-09-patch1
// @description utils of hook javascript function and value changes for js reverse engineering
// @author @Esonhugh
// @match http://*
// @match https://*
// @include http://*
// @include https://*
// @icon https://blog.eson.ninja/img/reol.png
// @grant none
// @license MIT
// @run-at document-start
// ==/UserScript==
(function () {
console.hooks = {
// settings
settings: {
// trigger debugger if hook is caught
autoDebug: false,
// don't let page jump to other place
blockPageJump: false,
// log prefix
prefix: "[EHOOKS] ",
// init with eventListener added
checkEventListnerAdded: false,
// init with cookie change listener
checkCookieChange: false,
// init with localstorage get set
checkLocalStorageGetSet: false,
// anti dead loop debugger in script
antiDeadLoopDebugger: true,
// hidden too many logs
hiddenlog: false,
},
rawlog: function (...data) {
if (this.settings.hiddenlog) {
return; // don't print
}
return console.debug(...data);
},
log: console.warn,
debugger: function () {
// traped in debug
if (this.settings.autoDebug) {
debugger;
}
},
hooked: {},
dumpstack() {
var err = new Error();
this.log(err.stack.split("\n").slice(2) // delete Error and dumpstack self
.reverse().concat(`${this.settings.prefix}Stack Dump -> STACK TOP`).reverse()
// add StackDump message at top
.join("\n"))
},
dumpHooked() {
for (var i in this.hooked) {
this.log(`${i}: `, this.hooked[i]);
}
},
hookfunc: function (
object,
functionName,
posthook = () => {},
prehook = () => {}
) {
(function (originalFunction) {
object[functionName] = function () {
// hook logic
// 1. Allow Check
var args = prehook([originalFunction, arguments, this]);
var realargs = arguments;
if (args) {
realargs = args;
} else {
realargs = arguments;
}
// 2. Execute old function
var returnValue = originalFunction.apply(this, realargs);
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook function trap-> func[${functionName}]`,
"args->",
realargs,
"ret->",
returnValue
);
console.hooks.debugger();
// 3. Post hook change values
var newReturn = posthook([
returnValue,
originalFunction,
realargs,
this,
]);
if (newReturn) {
return newReturn;
}
return returnValue;
};
object[functionName].toString = function () {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Found hook toString check!`,
originalFunction
);
console.hooks.debugger();
return originalFunction.toString();
};
console.hooks.hooked[functionName] = originalFunction;
})(object[functionName]);
this.rawlog(
`${console.hooks.settings.prefix}Hook function`,
functionName,
"success!"
);
},
unhookfunc: function (object, functionName) {
object[functionName] = console.hooks.hooked[functionName];
this.rawlog(
`${console.hooks.settings.prefix}unHook function`,
functionName,
"success!"
);
},
hookCookie: function () {
try {
var cookieDesc =
Object.getOwnPropertyDescriptor(Document.prototype, "cookie") ||
Object.getOwnPropertyDescriptor(HTMLDocument.prototype, "cookie");
if (cookieDesc && cookieDesc.configurable) {
this.hooked["Cookie"] = document.cookie;
Object.defineProperty(document, "cookie", {
set: function (val) {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook捕获到cookie设置->`,
val
);
console.hooks.debugger();
console.hooks.hooked["Cookie"] = val;
return val;
},
get: function () {
return (console.hooks.hooked["Cookie"] = "");
},
configurable: true,
});
} else {
var org = document.__lookupSetter__("cookie");
document.__defineSetter__("cookie", function (cookie) {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Cookie Set as`,
cookie
);
console.hooks.debugger();
org = cookie;
});
document.__defineGetter__("cookie", function () {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Cookie Got`,
org
);
console.hooks.debugger();
return org;
});
}
} catch (e) {
this.rawlog(`${console.hooks.settings.prefix}Cookie hook failed!`);
}
},
hookLocalStorage: function () {
this.hookfunc(localStorage, "getItem");
this.hookfunc(localStorage, "setItem");
this.hookfunc(localStorage, "removeItem");
this.hookfunc(localStorage, "clear");
this.rawlog(`${console.hooks.settings.prefix}LocalStorage hooked!`);
},
hookValueViaGetSet: function (name, obj, key) {
if (obj[key]) {
this.hooked[key] = obj[key];
}
var obj_name = `${name}.${key}`;
var org = obj.__lookupSetter__(key);
obj.__defineSetter__(key, function (val) {
org = console.hooks.hooked[key];
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook value set `,
obj_name,
"value->",
org,
"newvalue->",
val
);
console.hooks.debugger();
console.hooks.hooked[key] = val;
});
obj.__defineGetter__(key, function () {
org = console.hooks.hooked[key];
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook value get `,
obj_name,
"value->",
org
);
console.hooks.debugger();
return org;
});
},
hookValueViaProxy: function (name, obj, key = "default_all") {
var obj_name = "OBJ_" + name;
return new Proxy(obj, {
get: function (target, property, receiver) {
if (!target[property]) {
ret = undefined;
} else {
ret = target[property];
}
if (key === "default_all") {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook Proxy value get`,
`${obj_name}.${property}`,
"value->",
ret
);
console.hooks.debugger();
}
if (property == key && key != "default_all") {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook Proxy value get`,
`${obj_name}.${property}`,
"value->",
ret
);
console.hooks.debugger();
}
return target[property];
},
set: function (target, property, newValue, receiver) {
if (!target[property]) {
ret = undefined;
} else {
ret = target[property];
}
if (key === "default_all") {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook Proxy value set`,
`${obj_name}.${property}`,
"value->",
ret,
"newvalue->",
newValue
);
console.hooks.debugger();
}
if (property == key && key != "default_all") {
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook Proxy value get`,
`${obj_name}.${property}`,
"value->",
ret,
"newvalue->",
newValue
);
console.hooks.debugger();
}
target[property] = newValue;
return true;
},
});
},
hookEvents: function (params) {
var placeToReplace;
if (window.EventTarget && EventTarget.prototype.addEventListener) {
placeToReplace = EventTarget;
} else {
placeToReplace = Element;
}
this.hookfunc(
placeToReplace.prototype,
"addEventListener",
function (res) {
let [ret, originalFunction, arguments] = res;
console.hooks.rawlog(
`${console.hooks.settings.prefix}Hook event listener added!`,
arguments
);
}
);
},
antiDebuggerLoops: function () {
processDebugger = (type,res) => {
let [originalFunction, arguments, t] = res;
var handler = arguments[0];
console.hooks.debugger();
if (handler.toString().includes("debugger")) {
console.hooks.log(
`${console.hooks.settings.prefix}found debug loop in ${type}`
);
console.hooks.debugger();
let func = handler.toString().replaceAll("debugger", "");
arguments[0] = new Function("return " + func)();
return arguments;
} else {
return arguments;
}
};
this.hookfunc(
window,
"setInterval",
() => {},
(res)=>{return processDebugger("setInterval", res)}
);
this.hookfunc(
window,
"setTimeout",
() => {},
(res) => {return processDebugger("setTimeout", res)}
);
this.hookfunc(Function.prototype, "constructor", (res) => {
let [ret, originalFunction, arguments, env] = res;
if (ret.toString().includes("debugger")) {
console.hooks.log(
`${console.hooks.settings.prefix}found debug loop in Function constructor`
);
console.hooks.debugger();
let func = ret.toString().replaceAll("debugger", "");
return new Function("return " + func)();
}
return ret;
});
},
init: function () {
if (this.settings.blockPageJump) {
window.onbeforeunload = function () {
return "ANTI LEAVE";
};
}
if (this.settings.checkEventListnerAdded) {
this.hookEvents();
}
if (this.settings.checkCookieChange) {
this.hookCookie();
}
if (this.settings.checkLocalStorageGetSet) {
this.hookLocalStorage();
}
if (this.settings.antiDeadLoopDebugger) {
this.antiDebuggerLoops();
}
},
main: function () {
this.hookfunc(window, "eval");
this.hookfunc(window, "Function");
this.hookfunc(window, "atob");
this.hookfunc(window, "btoa");
this.hookfunc(window, "fetch");
this.hookfunc(window, "encodeURI");
this.hookfunc(window, "encodeURIComponent");
this.hookfunc(JSON, "parse");
this.hookfunc(JSON, "stringify");
this.hookfunc(console, "log");
// this.hookfunc(console, "warn")
// this.hookfunc(console, "error")
// this.hookfunc(console, "info")
// this.hookfunc(console, "debug")
// this.hookfunc(console, "table")
// this.hookfunc(console, "trace")
this.hookfunc(console, "clear");
},
};
// auto run init
console.hooks.init();
})();