How to modify odex file under the framework

Android system is generally divided into engineering version and user version. The system that ordinary users get is the user version, and the intuitive difference of the user version is that jar and apk files under /system/framework and /system/app are odex.

For odex under /system/app, we can use baksmali tool to decompile smali file. After modifying some smali files, we use the dexopt-wrapper tool to make odex on the target machine, and then push it to /system/app. However, for files under the framework, it is generally not possible to modify them in this way. After modification, when you push them under /system/framework, the system will usually hang. If the files under the framework can't be modified, isn't it fun to play Android?

How to edit the ODEX framework file?

This method needs to be improved to be suitable for various models.

There are two main reasons why odex under the framework can't run when it is packaged, decompiled and pushed to the machine.

The first point is that many jar packages under the framework are boot classpaths that dalvik virtual needs to use. Android has a special security mechanism for this, so we need to add $ boot classpaths when making odex.

The second point is the signature problem. If the previous one is wrong, then fail will still start, which can be solved by copying the original odex file header.

Specific methods, we take the following example, modify android.policy.odex as an example.

We extract android.policy.odex and android.policy.jar from the target machine, then use baksmali to modify smali, use smali tool to package it into classes.dex, and then replace it with android. Policy. jar.

Let's start our text method:

1, create a zangcf_changed directory and zangcf_original directory in /data/local/tmp.

ADB Shell

cd /data/local/tmp

mkdir zangcf_changed

mkdir zangcf_original

export

2. Copy the original file and the modified file to the target machine.

ADB Shell

Adb pushes. /zang cf _ changed/Android . policy . jar/data/local/tmp/zang cf _ changed/

Adb pushes. /zang cf _ original/Android . policy . jar/data/local/tmp/zang cf _ original/

Adb pushes. /zang cf _ original/Android . policy . odex/data/local/tmp/zang cf _ original/

export

3. Prepare the execution environment

Adb shell

Soviet Union (short for USSR)

Install -o rw, reinstall/system.

chmod 777 /system/bin

Chmod 777/ system/framework/

export

Adb pushes. /dexopt-wrapper /system/bin

Adb shell

Soviet Union (short for USSR)

chmod 777/system/bin/dex opt-wrapper

export

4、odex

Adb shell

Soviet Union (short for USSR)

CP/data/local/tmp/zang cf _ changed/Android . policy . jar/system/framework/Android . policy . jar

dex opt-wrapper/system/framework/Android . policy . jar/system/framework/new _ Android . policy . odex＄boot class path

CP-f/SD card/ame stris _ original/Android . policy . jar/system/framework

chmod 777/system/framework/Android . policy . odex

chmod 777/system/framework/Android . policy . jar

chmod 777/system/framework/new _ Android . policy . odex

export

5. Copy the header of the original file.

Adb shell

Soviet Union (short for USSR)

busybox DD if =/system/framework/Android . policy . odex of =/system/framework/new _ Android . policy . odex bs = 1 count = 20 skip = 52 seek = 52 conv = not runc

CP/system/framework/new _ Android . policy . odex/system/framework/Android . policy . odex

export

6. Delete temporary files and modify file properties.

ADB Shell

Soviet Union (short for USSR)

chmod 644/system/framework/Android . policy . odex

chown root . root/system/framework/Android . policy . odex

RM/system/framework/new _ Android . policy . odex

export

7, ok, and then restart

ADB restarts.

Inspirational signature excerpt