ccm

#!/usr/bin/python3

import sys
import argparse 

from ccm import CryptedCookie, CcmException


parser = argparse.ArgumentParser(description='''ccm is a command line utility that uses the ccm library to assist 
                                                finding vulnerabilities in the handling of encrypted data. It can
                                                be used to generate wordlists (bitflipping, block shuffling, padding
                                                oracle) based on an initial input value. While the initial purpose of
                                                this tool was originally to deal with encrypted cookies, it can be used
                                                for any kind of encrypted data.''')

parser.add_argument('blob', help='encrypted input value')
parser.add_argument('--aimed-flip', dest='aimed_flip', nargs=2, default=None, metavar=('current', 'desired'), help='deterministically flip a whole string')
parser.add_argument('--block', metavar='int', dest='block', action='append', default=[], type=int, help='specify blocks to shuffle')
parser.add_argument('--bit-flip', dest='bit_flip', action='store_true', help='create a bitflipping wordlist')
parser.add_argument('--block-size', metavar='int', dest='blocksize', default=None, type=int, help='blocksize of the encrypted data')
parser.add_argument('--encoding', metavar='(b64|hex)', choices=['b64', 'hex'], dest='encoding', help='encoding of the encrypted data')
parser.add_argument('--end-block', metavar='int', dest='end_block', default=None, type=int, help='block number to end with (index, including)')
parser.add_argument('--end-byte', metavar='int', dest='end_byte', default=None, type=int, help='byte position to end with (index, including)')
parser.add_argument('--keep', action='store_true', help='keep the original blocks during shuffle operations')
parser.add_argument('--max-byte', metavar='int', dest='max_byte', default=None, type=int, help='maximum byte for bitflipping attacks')
parser.add_argument('--min-byte', metavar='int', dest='min_byte', default=None, type=int, help='minimum byte for bitflipping attacks')
parser.add_argument('--padding', dest='padding', action='store_true', help='create a padding oracle wordlist')
parser.add_argument('--shuffle', dest='shuffle', action='store_true', help='create shuffle wordlist (move 1 at the time)')
parser.add_argument('--full-shuffle', dest='fshuffle', action='store_true', help='create a shuffle wordlist (all permutations)')
parser.add_argument('--start-block', metavar='int', dest='start_block', default=None, type=int, help='block number to start with (index, including)')
parser.add_argument('--start-byte', metavar='int', dest='start_byte', default=None, type=int, help='byte position to start with (index, including)')


def main():
    '''
    Start ccm. Behavior is controlled by the arguments received from argparse

    Parameters:
        None

    Returns:
        None
    '''
    args = parser.parse_args()

    blocksize = args.blocksize
    if args.blocksize:
        blocksize = [args.blocksize]

    try:
        cookie = CryptedCookie(args.blob, blocksize, args.encoding)

        if args.aimed_flip:
            current = args.aimed_flip[0]
            desired = args.aimed_flip[1]
            generator = cookie.aimed_flipping_generator(current, desired, args.start_byte, args.end_byte, args.start_block, args.end_block)

        elif args.bit_flip:
            generator = cookie.flipping_generator(args.start_byte, args.end_byte, args.start_block, args.end_block, args.min_byte, args.max_byte)

        elif args.padding:
            generator = cookie.padding_generator()

        elif args.fshuffle:

            if args.start_byte or args.end_byte:
                raise CcmException("Shuffle operations only allow '--start-block' or '--end-block' to be used.")

            generator = cookie.full_shuffeling_generator(args.start_block, args.end_block)

        elif args.shuffle:

            if args.start_byte or args.end_byte:
                raise CcmException("Shuffle operations only allow '--start-block' or '--end-block' to be used.")

            generator = cookie.shuffeling_generator(args.start_block, args.end_block, args.block, args.keep)

        else:
            cookie.print_info()
            sys.exit(0)

        for item in generator:
            print(item)

        sys.exit(0)

    except CcmException as e:
        print('[-] Error: ' + str(e))
        sys.exit(1)


if __name__ == '__main__': 
    main()