第一课时 Hook In Java

vscode中自动提示npm i @types/froda-gum

hook java层代码

function hook_java() {
    Java.perform(function() {
    var clazz = Java.use("java class")          // Java.use 是java的类包装器
    clazz.a.implementation = function(str, str2) { // a为函数
      var result = this.a(str, str2);
    }   
  })    
}

开启frida frida -U packageName -l hook.js

调用函数，静态的能直接调用，非静态的要用Java.Choose来调用函数

function call_FridaActivity2() {
    //主动调用函数
    Java.perform(function () {
        var FridaActivity2 = Java.use("com.example.androiddemo.Activity.FridaActivity2");
        FridaActivity2.setStatic_bool_var();    //调用静态函数
                // 非静态 要找到对象
        Java.choose("com.example.androiddemo.Activity.FridaActivity2", {
            onMatch: function (instance) {
                instance.setBool_var();
            },
            onComplete: function () {

            }
        });
    });
}

直接设置类中的变量，静态的值就直接修改即可，非静态的需要获取他的对象在修改，如果函数的名字和变量一样，就要在变量前面加个下划线。

function call_FridaActivity3() {
    Java.perform(function () {
        var FridaActivity3 = Java.use("com.example.androiddemo.Activity.FridaActivity3");
        FridaActivity3.static_bool_var.value = true;        //设置静态成员变量

        console.log(FridaActivity3.static_bool_var.value);

        Java.choose("com.example.androiddemo.Activity.FridaActivity3", {
            onMatch: function (instance) {
                //设置非静态成员变量的值
                instance.bool_var.value = true;
                //设置有相同函数名的成员变量的值
                instance._same_name_bool_var.value = true;
                console.log(instance.bool_var.value, instance._same_name_bool_var.value);
            },
            onComplete: function () {

            }
        });
    });
}

内部类的函数

function hook_InnerClasses() {
    Java.perform(function () {
        //hook内部类
        var InnerClasses = Java.use("com.example.androiddemo.Activity.FridaActivity4$InnerClasses");
        console.log(InnerClasses);
        InnerClasses.check1.implementation = function () {
            return true;
        };
        InnerClasses.check2.implementation = function () {
            return true;
        };
        InnerClasses.check3.implementation = function () {
            return true;
        };
        InnerClasses.check4.implementation = function () {
            return true;
        };
        InnerClasses.check5.implementation = function () {
            return true;
        };
        InnerClasses.check6.implementation = function () {
            return true;
        };
    });
}

hook 多个函数的

function hook_mul_function() {
    Java.perform(function () {
        //hook 类的多个函数
        var class_name = "com.example.androiddemo.Activity.FridaActivity4$InnerClasses";
        var InnerClasses = Java.use(class_name);
        var all_methods = InnerClasses.class.getDeclaredMethods();
        for (var i = 0; i < all_methods.length; i++) {
            var method = (all_methods[i]);
            var methodStr = method.toString();
            var substring = methodStr.substr(methodStr.indexOf(class_name) + class_name.length + 1);
            var methodname = substring.substr(0, substring.indexOf("("));
            console.log(methodname);

            InnerClasses[methodname].implementation = function () {
                console.log("hook_mul_function:", this);
                return true;
            }

        }

    });
}

hook 动态的dex，

unction hook_dyn_dex() {
    Java.perform(function () {
        var FridaActivity5 = Java.use("com.example.androiddemo.Activity.FridaActivity5");
        Java.choose("com.example.androiddemo.Activity.FridaActivity5", {
            onMatch: function (instance) {
                console.log(instance.getDynamicDexCheck().$className);
            }, onComplete: function () {

            }
        });


        //hook 动态加载的dex
        Java.enumerateClassLoaders({
            onMatch: function (loader) {
                try {
                    if (loader.findClass("com.example.androiddemo.Dynamic.DynamicCheck")) {
                        console.log(loader);
                        Java.classFactory.loader = loader;      //切换classloader
                    }
                } catch (error) {

                }

            }, onComplete: function () {

            }
        });

        var DynamicCheck = Java.use("com.example.androiddemo.Dynamic.DynamicCheck");
        console.log(DynamicCheck);
        DynamicCheck.check.implementation = function () {
            console.log("DynamicCheck.check");
            return true;
        }
    });
}