Android逆向|Xposed Hook(下)

admin 2022年5月3日00:55:32评论157 views字数 4200阅读14分0秒阅读模式

本篇是《Android逆向入门教程》的第八章第1.4节,具体课程详情可点击下方图片查看:

Android逆向|Xposed Hook(下)

每一章节详细内容及实验材料可通过加入底部免费的【Android逆向成长计划】星球获得!


声明:所有实验含部分虚构,纯属技术练习,未对真实环境造成任何影响。也请勿将相关技术用于非法操作,否则责任自负。


0x01 Hook替换函数与函数置空

在我们Hook的时候,常用的回调函数是XC_MethodHook(),用来获取或者修改我们Hook的参数列表。除了这个回调函数外,还有一个XC_MethodReplacement()函数,用来替换要Hook的函数或者将Hook的函数置空。实现代码如下:

package com.xposed;

import android.util.Log;import de.robv.android.xposed.IXposedHookLoadPackage;import de.robv.android.xposed.XC_MethodReplacement;import de.robv.android.xposed.XposedHelpers;import de.robv.android.xposed.callbacks.XC_LoadPackage.LoadPackageParam;

public class Hook implements IXposedHookLoadPackage {public void handleLoadPackage(final LoadPackageParam lpparam) throws Throwable {if (lpparam.packageName.equals("com.feichen.xposeddemo")){final Class<?> clazz = XposedHelpers.findClass("com.feichen.xposeddemo.Demo",lpparam.classLoader);XposedHelpers.findAndHookMethod(clazz,"test",new XC_MethodReplacement(){@Overrideprotected Object replaceHookedMethod(MethodHookParam param)throws Throwable {Log.d("====================", "replaceHook");return null;}});}}}

日志输出效果图如下:

Android逆向|Xposed Hook(下)

可以发现test()函数已经被我们成功的替换掉,同理当我们什么也不写只返回Null就相当于将Hook的函数置空。


0x02 Hook内部类与匿名类

在Hook的时候,我们经常也会遇到一些内部类以及匿名内部类,我们还是以之前的案例为例进行说明。

Android逆向|Xposed Hook(下)

Android逆向|Xposed Hook(下)

然后编写我们的Hook代码如下:

package com.xposed;

import android.util.Log;import de.robv.android.xposed.IXposedHookLoadPackage;import de.robv.android.xposed.XC_MethodReplacement;import de.robv.android.xposed.XposedHelpers;import de.robv.android.xposed.callbacks.XC_LoadPackage.LoadPackageParam;

public class Hook implements IXposedHookLoadPackage {public void handleLoadPackage(final LoadPackageParam lpparam) throws Throwable {if (lpparam.packageName.equals("com.feichen.xposeddemo")){final Class<?> clazz = XposedHelpers.findClass("com.feichen.xposeddemo.Demo$InnerClass",lpparam.classLoader);XposedHelpers.findAndHookMethod(clazz,"innerFunc",String.class,new XC_MethodReplacement(){@Overrideprotected Object replaceHookedMethod(MethodHookParam param)throws Throwable {Log.d("====================", "我是被替换的内部类");return null;}});final Class<?> clazz1 = XposedHelpers.findClass("com.feichen.xposeddemo.Demo$1",lpparam.classLoader);XposedHelpers.findAndHookMethod(clazz1,"eatFunc",String.class,new XC_MethodReplacement(){@Overrideprotected Object replaceHookedMethod(MethodHookParam param)throws Throwable {Log.d("====================", "我是被替换的匿名内部类");return null;}});}}}

Hook日志如下:

Android逆向|Xposed Hook(下)

我们通过编写的Hook代码可以发现,Hook内部类的字节码为:类路径$类名

Hook匿名内部类的字节码为:类路径$1  类路径$2  类路径$3


0x03 Xposed主动调用

在Hook的时候,我们有时候也是需要对app内部的函数进行主动调用,其中主动调用的函数为XposedHelpers.callMethod(),他的第一个参数为类的实例即clazz.newInstance(),第二个参数是方法名,第三个参数是参数列表,对于没有参数的函数可省略。那我还是以上个案例为例,找到其中的一个未被调用的函数refl()

Android逆向|Xposed Hook(下)

然后编写Hook代码如下:

package com.xposed;

import android.util.Log;import de.robv.android.xposed.IXposedHookLoadPackage;import de.robv.android.xposed.XC_MethodReplacement;import de.robv.android.xposed.XposedHelpers;import de.robv.android.xposed.callbacks.XC_LoadPackage.LoadPackageParam;

public class Hook implements IXposedHookLoadPackage {public void handleLoadPackage(final LoadPackageParam lpparam) throws Throwable {if (lpparam.packageName.equals("com.feichen.xposeddemo")){final Class<?> clazz = XposedHelpers.findClass("com.feichen.xposeddemo.Demo$InnerClass",lpparam.classLoader);XposedHelpers.findAndHookMethod(clazz,"innerFunc",String.class,new XC_MethodReplacement(){@Overrideprotected Object replaceHookedMethod(MethodHookParam param)throws Throwable {Log.d("====================", "我是被替换的内部类");return null;}});final Class<?> clazz1 = XposedHelpers.findClass("com.feichen.xposeddemo.Demo$1",lpparam.classLoader);XposedHelpers.findAndHookMethod(clazz1,"eatFunc",String.class,new XC_MethodReplacement(){@Overrideprotected Object replaceHookedMethod(MethodHookParam param)throws Throwable {Log.d("====================", "我是被替换的匿名内部类");return null;}});//主动调用final Class<?> clazz2 = XposedHelpers.findClass("com.feichen.xposeddemo.Demo",lpparam.classLoader);XposedHelpers.callMethod(clazz2.newInstance(),"refl");}}}

运行日志如下:

Android逆向|Xposed Hook(下)


发现已经成功主动调用到该函数。



团队公开知识库链接:

https://www.yuque.com/books/share/f7515884-c39f-4d2b-ab15-55921c8205b8?# 《WhITECat公开知识积累》密码:kstn

知识星球:

Android逆向|Xposed Hook(下)

Android逆向|Xposed Hook(下)

往期经典


Android逆向入门成长计划【免费知识星球+微信交流群】

《从入门到秃头之PWN蛇皮走位》

漏洞挖掘|条件竞争在漏洞挖掘中的妙用

漏洞笔记|记一次与XXE漏洞的爱恨纠缠

移动安全-APP渗透进阶之AppCan本地文件解密

内网渗透之从信息收集到横向独家姿势总结-linux篇

HVV前奏|最新版AWVS&Nessus破解及批量脚本分享

Android抓包总结-HTTPS单向认证&双向认证突破

图形验证码绕过新姿势之深度学习与burp结合


Android逆向|Xposed Hook(下)

扫描二维码 |关注我们



原文始发于微信公众号(WhITECat安全团队):Android逆向|Xposed Hook(下)

  • 左青龙
  • 微信扫一扫
  • weinxin
  • 右白虎
  • 微信扫一扫
  • weinxin
admin
  • 本文由 发表于 2022年5月3日00:55:32
  • 转载请保留本文链接(CN-SEC中文网:感谢原作者辛苦付出):
                   Android逆向|Xposed Hook(下)http://cn-sec.com/archives/967254.html

发表评论

匿名网友 填写信息