t48.py

import binascii
import struct
import hexdump
import glob
from collections import namedtuple, OrderedDict


def xorbytes(a, b):
    c = bytearray()
    for i in range(len(a)):
        c.append(a[i] ^ b[i])
    return c


FILE_HEADER = struct.Struct("<BBHI4xI")
FileHeader = namedtuple('FileHeader', ['minor_version', 'major_version', 'magic', 'crc32',
                                       'num_blocks'])
BLOCK = struct.Struct("<III4x 260s")
Block = namedtuple('Block', ['crc32', 'index', 'unknown', 'data'])

def read_file(filename):
    with open(filename, "rb") as fil:
        filedata = fil.read()

        file_header = FileHeader(*FILE_HEADER.unpack(filedata[:FILE_HEADER.size]))

        blocks = OrderedDict()
        offset = FILE_HEADER.size
        for i in range(file_header.num_blocks):
            block = Block(*BLOCK.unpack(filedata[offset:offset + BLOCK.size]))
            blocks[block.crc32] = block
            offset += BLOCK.size

        return file_header, blocks


if 1:
    files = {}
    for filename in glob.glob("./UpdateT48*.dat"):
        files[filename] = read_file(filename)

    for i in files.keys():
        fil1 = files[i]
        for j in files.keys():
            if i == j:
                continue
            fil2 = files[j]

            identical = len(fil1[1].keys())
            for k, crc32 in enumerate(fil1[1].keys()):
                if crc32 in fil2[1].keys():
                    xored = xorbytes(fil1[1][crc32].data, fil2[1][crc32].data)
                    if fil1[1][crc32].index != fil2[1][crc32].index and b"\x00\x00" in xored:
                        print(hex(k), hex(crc32), i, hex(fil1[1][crc32].index), j,
                              hex(fil2[1][crc32].index))
                    # if crc32 in ffs:
                        # print("FOUND!")
                    # print(i, j)
                        print(hexdump.hexdump(xorbytes(fil1[1][crc32].data, fil2[1][crc32].data)))
                    # break
                    identical -= 1

            # print("%s and %s are identical: %d" % (i, j, identical))

# fil1 = read_file("UpdateT48_V1223.dat")
# fil2 = read_file("UpdateT48_V1225.dat")
# identical = len(fil1[1].keys())
# for k, crc32 in enumerate(fil1[1].keys()):
    # if crc32 in fil2[1].keys():
        # print(hex(k), hex(crc32), hex(fil1[1][crc32].index), hex(fil2[1][crc32].index))
        # # if crc32 in ffs:
            # # print("FOUND!")
        # # print(i, j)
        # print(hexdump.hexdump(xorbytes(fil1[1][crc32].data, fil2[1][crc32].data)))
        # # break

# open("1230x1232.dat", "wb").write(xorbytes(open("UpdateT48_V1232.dat", "rb").read(),
                                           # open("UpdateT48_V1230.dat", "rb").read()))