解压华为P6 UPDATE.APP

#!/usr/bin/env python
# Version: 0.2.201308040830
# Author: linkscue
# Function: unpack any hauwei honor2 Update.app
# Thanks to McSpoon(zhaoxing-go@163.com)
# 20130411: Modified for alignment to 4 byte boundary by jnjn@163.com
# 20130804: Modified for python3 by atuo @ oschina.net

import os
import sys
import struct
from functools import reduce
print("Usage: unpack $huawei_app_file")
try:
    sys.argv[1]
except IndexError:
        File="UPDATE.APP"
else:
    File=sys.argv[1];

verify_code=0xa55aaa55
verify_bin=struct.pack("I",verify_code)

print("I: unpack",File)
f=open(File,'rb')
cont=f.read()
f.close()

start=0
sub_file=1
search=verify_bin
while True:
    index = cont.find(search, start)
    if index == -1:
        break

    if ((index) % 4  != 0 ):
        print("skipping a 55aa5aa5 at offset: 0x%08xn" % (index))
        start = index + 1
    else:
        packet_addr=cont[index+4:index+8]
        data_addr=cont[index+24:index+28]
        img_name=cont[index+60:index+76]
        packet_size_tuple=struct.unpack("I",packet_addr)
        data_size_tuple=struct.unpack("I",data_addr)
        packet_size=int(reduce(lambda rst, d: rst * 10 + d, packet_size_tuple))
        data_size=int(reduce(lambda rst, d: rst * 10 + d, data_size_tuple))
        temp=cont[index+packet_size:index+packet_size+data_size]
        filename=str(sub_file)+'_'+img_name.strip(b'x00').decode('ascii')+'.img'
        print( "%2d I: verify code found at: 0x%08x, size: %10d bytes, --> %-20s"
        % (sub_file,index,data_size,filename) )
        f1=open(filename,'wb')
        f1.write(temp)
        f1.close()
        start = index + 1
        sub_file += 1