BMADecoder.py

import sys, binascii, string, re
import xml.etree.ElementTree

def decrypt(encoded):
    key = 0x398e27fc50276a656065b0e525f4c06c04c61075286b8e7aeda59da9813b5dd6c80d2fb38068773fa59ba47c17ca6c6479015c1d5b8b8f6b9a
    output = hex(key^(int(encoded, 16)))
    binary_output = binascii.unhexlify(output[2:116]) # needed to drop the 0x at the beginning

    return (binascii.b2a_qp(binary_output[0:40]), binascii.b2a_qp(binary_output[40:57]))

def main():
    # Find file on your device at "/data/data/com.blizzard.bma/shared_prefs/com.blizzard.bma.AUTH_STORE.xml"
    filename = "/home/yourname/backup/authstore.xml"
    e = xml.etree.ElementTree.parse(filename).getroot()

    serial = e.find('string').text

    out = decrypt(serial)
    print "Token: ", out[0]
    print "Serial: ", out[1]

if __name__ == '__main__':
    main()