Frida构造数组，对象，Map和类参数
- 数组/（字符串）对象数组/gson/Java.array
- 对象/多态，强转Java.cast
- 接口interface，Java.register
- 枚举，泛型，List,Map,Set,迭代打印
- 重要思路:开发时如何打印，frida中也是如何打印
- non-ascii 方法名 hook
0x01
1.app代码:
Log.d(“SimpleArray”, “onCreate: SImpleArray”);
char arr[][] = new char[4][]; // 创建一个4行的二维数组
arr[0] = new char[] { ‘春’, ‘眠’, ‘不’, ‘觉’, ‘晓’ }; // 为每一行赋值
arr[1] = new char[] { ‘处’, ‘处’, ‘闻’, ‘啼’, ‘鸟’ };
arr[2] = new char[] { ‘夜’, ‘来’, ‘风’, ‘雨’, ‘声’ };
arr[3] = new char[] { ‘花’, ‘落’, ‘知’, ‘多’, ‘少’ };
Log.d(“SimpleArray”, “—–横版—–“);
for (int i = 0; i < 4; i++) { // 循环4行
//Log.d(“SimpleArraysToString”, Arrays.toString(arr[i]));
//Log.d(“SimpleStringBytes”, Arrays.toString (Arrays.toString (arr[i]).getBytes()));
for (int j = 0; j < 5; j++) { // 循环5列
Log.d(“SimpleArray”, Character.toString(arr[i][j])); // 输出数组中的元素
}
if (i % 2 == 0) {
Log.d(“SimpleArray”, “,”);// 如果是一、三句，输出逗号
} else {
Log.d(“SimpleArray”, “。”);// 如果是二、四句，输出句号
}
}
这里直接hook java.lang.Character的toString方法，打印出参数和返回值
function main()
{
Java.perform(function(){
Java.use(“java.lang.Character”).toString.overload(‘char’).implementation=function(arg1)
{
var result=this.toString(arg1);
console.log(“x,result”,arg1,result);
return result;
}
})
}
setImmediate(main);
2.对象数组
这里引出一个参数为char类型的数组，hook一下
function main()
{
Java.perform(function(){
Java.use(“java.lang.Character”).toString.overload(‘char’).implementation=function(arg1)
{
var result=this.toString(arg1);
console.log(“x,result”,arg1,result);
return result;
}
Java.use(“java.util.Arrays”).toString.overload(‘[C’).implementation=function(x)
{
var result=this.toString(x);
console.log(“x,result”,x,result);
return result;
}
})
}
setImmediate(main);
这里发现hook出来的参数发现无法打印出来，两个都是Object类型，需要有特殊的操作
1. 使用Json.stringify(x)方法可以打印出Object
Java.use(“java.util.Arrays”).toString.overload(‘[C’).implementation=function(x)
{
var result=this.toString(x);
console.log(“x,result”,JSON.stringify(x),result);
return result;
}
- 肉丝表哥自己编译的一个gson包来处理
先将下载好的dex文件放入/data/local/tmp目录下，然后frida动态加载dex，调用其中方法
function main()
{
Java.perform(function(){
/*Java.use(“java.lang.Character”).toString.overload(‘char’).implementation=function(arg1)
{
var result=this.toString(arg1);
console.log(“x,result”,arg1,result);
return result;
}*/
Java.openClassFile(“/data/local/tmp/r0gson.dex”).load();
const gson=Java.use(“com.r0ysue.gson.Gson”);
Java.use(“java.util.Arrays”).toString.overload(‘[C’).implementation=function(x)
{
var result=this.toString(x);
console.log(“x,result”,gson.$new().toJson(x),result);
return result;
}
})
}
setImmediate(main);
3.自己构造一个char数组对象(Java.array)
function main()
{
Java.perform(function(){
/*Java.use(“java.lang.Character”).toString.overload(‘char’).implementation=function(arg1)
{
var result=this.toString(arg1);
console.log(“x,result”,arg1,result);
return result;
}*/
Java.openClassFile(“/data/local/tmp/r0gson.dex”).load();
const gson=Java.use(“com.r0ysue.gson.Gson”);
Java.use(“java.util.Arrays”).toString.overload(‘[C’).implementation=function(x)
{
var charArray=Java.array(‘char’,[‘1′,’2′,’3′,’4′,’5’]);
var result=this.toString(charArray);
console.log(“x,result”,gson.$new().toJson(x),result);
return result;
}
})
}
setImmediate(main);
4.对象类型强制转换Java.cast
总体来说就是父类是无法强转成子类的，子类可以向上强转成父类的，然后就是查找对象时，有时候时机过早或过晚，会导致找不到实例，所以选择的话，选择延时hook，setTimeout(function,3000),然后用spawn方式启动app
function main()
{
Java.perform(function(){
/*Java.use(“java.lang.Character”).toString.overload(‘char’).implementation=function(arg1)
{
var result=this.toString(arg1);
console.log(“x,result”,arg1,result);
return result;
}*/
Java.openClassFile(“/data/local/tmp/r0gson.dex”).load();
const gson=Java.use(“com.r0ysue.gson.Gson”);
/*
Java.use(“java.util.Arrays”).toString.overload(‘[C’).implementation=function(x)
{
var charArray=Java.array(‘char’,[‘1′,’2′,’3′,’4′,’5’]);
var result=this.toString(charArray);
console.log(“x,result”,gson.$new().toJson(x),result);
return result;
}
*/
var waterhandle=null;
Java.choose(“com.r0ysue.a0526printout.Water”,{
onMatch:function(instance){
console.log(“found instance:”,instance);
console.log(“water call still:”,instance.still(instance));
waterhandle=instance;
},onComplete:function(){
console.log(“search completed”)
}
})
var JuiceHandle=Java.cast(waterhandle,Java.use(“com.r0ysue.a0526printout.Juice”));
console.log(“Juice fillEnergy method:”,JuiceHandle.fillEnergy());
var JuiceHandle=null;
Java.choose(“com.r0ysue.a0526printout.Juice”,{
onMatch:function(instance){
console.log(“found instance:”,instance);
console.log(“filling energy,”,instance.fillEnergy());
JuiceHandle=instance;
},onComplete:function(){“Search Completed”}
})
var waterhandle=Java.cast(JuiceHandle,Java.use(“com.r0ysue.a0526printout.Water”));
console.log(“Water invoke kill”);
})
}
setImmediate(main);
5。接口
可以在frida中创建一个java类，实现java层中的接口，案例:
var beer=Java.registerClass({
name:”com.r0ysue.a0526printout.beer”,
implements:[Java.use(‘com.r0ysue.a0526printout.liquid’)],
methods:{
flow:function(){
console.log(“look I’m beer”);
return “taste good”;
}
}
});
console.log(“beer.flow”,beer.$new().flow())
})
这里就是新建一个类实现了对应的接口
6.枚举
Java.choose(“com.r0ysue.a0526printout.Signal”,{
onMatch:function(instance){
console.log(“found instance:”,instance)
console.log(“invoke getDeclaringClass”,instance.getDeclaringClass());
},onComplete:function(){console.log(“Search Completed!”)}
})
})
枚举可以直接看成是一个类，那么这样对frida来说就是小菜一碟了
7.泛型，List,Map,Set,迭代打印
- Map
function hashmap888()
{
Java.perform(function(){
Java.choose(“java.util.HashMap”,{
onMatch:function(instance){
if(instance.toString().indexOf(“Sim”))
{
console.log(“found instance”,instance);
console.log(“HashmapString”,instance.toString());
}
},onComplete:function(){console.log(“search Completed!”)}
})
})
}
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[安全狗的自我修养](https://mp.weixin.qq.com/s/E6Kp0fd7_I3VY5dOGtlD4w)
[github haidragon](https://github.com/haidragon)
https://github.com/haidragon
原文地址：http://www.cnblogs.com/haidragon/p/16879570.html
