#!/usr/bin/python3
# MStar firmware decryption tool
from Crypto.Cipher import AES
import sys

key = 4 * b'\x12\x34\x56\x78'
aes = AES.new(bytes(key), AES.MODE_ECB)

for filename in sys.argv[1:]:
    with open(filename, 'rb') as f:
        data = f.read()
    dec = aes.decrypt(data[:(len(data)-16)&~0xf])
    with open(filename + '.out', 'wb') as f:
        f.write(dec)