mstar-bin-tool

Command line tools to pack/unpack MStar bin firmware

Currently available tools:

• unpack.py - unpack MStar bin firmware
• pack.py - pack MStar bin firmware
• extract_keys.py - extract AES and RSA-public keys from MBOOT binary
• secure_partition.py - encrypt image and generate signature file

Unpack MStar bin firmware files

Usage: unpack.py <firmware> <output folder [default: ./unpacked/]>
        <firmware> - MStar bin firmware to unpack
        <output folder> - directory to store unpacked stuff. Default value: ./unpacked/

Pack MStar bin firmware

Usage: pack.py <config file>
Example: pack.py configs/letv-x355pro-full.ini
        <config file> - Configuration file. The config file structure will be described later.
                        For now you can take a look at configs/letv-x355pro-full.ini
                        and use it as an example

Extract keys from MBOOT

That tool is used to get AES and public RSA keys from the MBOOT. AES keys are needed to encrypt/decrypt boot.img and recovery.img images. aescrypt2 tool is used.

Usage: extract_keys.py <path to mboot> [<folder to store keys>] [<key bank offset>] [<key bank size>]
Defaults:
          <folder to store keys>        keys
          <key bank offset>             0x168e00
          <key bank size>               0x450
Example: extract_keys.py ./unpacked/MBOOT.img
Example: extract_keys.py ./unpacked/MBOOT.img ./keys 0x169e00 0x450

Encrypt/Decrypt partition

You can encrypt/decrypt partition with using aescrypt2.exe tool, which is located in bin/win32 folder

Default mstar key is hex:0007FF4154534D92FC55AA0FFF0110E0 All mstar default keys are in default_keys folder. (These keys are in public access in github)

Last parameter can be hex value or path to AES key. If your vendor is using custom aes keys you can use extract_keys.py to extract them.

To encrypt image use:

aescrypt2 0 boot.img boot.img.aes hex:0007FF4154534D92FC55AA0FFF0110E0
or
aescrypt2 0 boot.img boot.img.aes keys/AESBootKey

So to decrypt image use:

aescrypt2 1 boot.img.aes boot.img hex:0007FF4154534D92FC55AA0FFF0110E0
or
aescrypt2 1 boot.img boot.img.aes keys/AESBootKey

Encrypt partition and generate signature

All new MStar builds have SECURE_BOOT option enabled. In that case boot.img and recovery.img is encrypted (AES) and signed with RSA priv keys. That script is used to encrypt image and generate sign file.

To manually encrypt|decrypt image use aescrypt2 tool from bin folder. AES key can be extracted from MBOOT with extract_keys.py script.

Usage: secure_partition.py <file to encrypt> <AES key file> <RSA private key file> <RSA public key file> <output encrypted file> <output signature file>
Example: secure_partition.py ./pack/boot.img ./keys/AESbootKey ./keys/RSAboot_priv.txt ./keys/RSAboot_pub.txt ./pack/boot.img.aes ./pack/bootSign