Super-Optimistic Disk Image Password-Guesser: ./unlock.py foo.dmg 6

unlock.py

#!/usr/bin/env python

import sys, time, string, logging, itertools, subprocess, multiprocessing

hdiutil_opts = [
    '-quiet', '-readonly', '-stdinpass', '-nomount', '-noverify', '-noautofsck', '-noidme', '-noautoopen'
]

def mount(image, queue):
    """Worker to attempt to mount the image. Return if successful or poisoned."""

    while True:
        password = queue.get()
        if password is None:
            logging.info("Oh, I am slain!")
            return

        logging.info("Trying: {0}".format(password))
        process = subprocess.Popen(
            ['hdiutil', 'mount', image] + hdiutil_opts,
            stdin=subprocess.PIPE
        )
        process.communicate(password)

        if not process.wait():
            logging.info("Success: {0}".format(password))
            queue.close()
            return
        logging.info("Failed: {0}".format(password))

if __name__ == '__main__':
    logging.basicConfig(level=logging.INFO, format='%(asctime)s: %(message)s')
    image = sys.argv[1]
    length = int(sys.argv[2])
    processes = 20  # multiprocessing.cpu_count() * 4
    queue = multiprocessing.Queue(processes * 2)
    
    # start the workers
    for _ in range(processes):
        multiprocessing.Process(target=mount, args=(image, queue)).start()

    # sequential iterator for passwords
    passwords = (
        ''.join(p)
        for p in itertools.chain.from_iterable(
            itertools.permutations(string.lowercase, w)
            for w in range(1, length + 1)
        )
    )

    try:
        for password in passwords:
            # don't overload queue
            while queue.full():
                time.sleep(0.1)
            queue.put(password)
    except KeyboardInterrupt:
        for _ in range(processes):
            queue.put(None)  # poison the workers. poison all of them!