Subversion Repositories freemyipod

#!/usr/bin/env python

#

#

#    Copyright 2010 TheSeven

#

#

#    This file is part of TheSeven's iPod tools.

#

#    TheSeven's iBugger is free software: you can redistribute it and/or

#    modify it under the terms of the GNU General Public License as

#    published by the Free Software Foundation, either version 2 of the

#    License, or (at your option) any later version.

#

#    TheSeven's iBugger is distributed in the hope that it will be useful,

#    but WITHOUT ANY WARRANTY; without even the implied warranty of

#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

#    See the GNU General Public License for more details.

#

#    You should have received a copy of the GNU General Public License along

#    with TheSeven's iPod tools.  If not, see <http://www.gnu.org/licenses/>.

#

#

import sys

import struct

from optparse import *

parser = OptionParser("usage: %prog [options] <infile> <outfile>")

parser.add_option("--signature", metavar = "SIGN",

                  help = "The device signature. Must be 4 characters, e.g. \"nn2x\". (mandantory)")

parser.add_option("--targetid", type = "int", metavar = "ID",

                  help = "The numeric target ID. (mandantory)")

(options, args) = parser.parse_args()

if len(args) != 2: parser.error("incorrect number of arguments")

if not options.signature: parser.error("please specify a device signature")

if not options.targetid: parser.error("please specify numeric target id")

if len(options.signature) != 4: parser.error("device signature must be 4 characters")

file = open(args[0], "rb")

data = file.read()

file.close()

checksum = options.targetid

for i in range(len(data)):

  checksum = (checksum  + struct.unpack("B", data[i])[0]) & 0xffffffff

file = open(args[1], "wb")

file.write(struct.pack(">I", checksum) + options.signature + data)

file.close()