Quick brute-force password finder of an encrypted zip file.

zip-password-finder.py

"""
Quick brute-force password finder of an encrypted zip file.
"Life's short, use Python."

by WKBae (https://github.com/WKBae/)
"""

import zipfile
from multiprocessing import Pool

# Unused character for marking 'end' of the list.
# Change if this character is used
dummy_char = '`'

# Whole list of the password letters, numbers(0-9) only
letters = [str(i) for i in range(10)] + [dummy_char]

# Including numbers, alphabets upper&lower cases
"""
letters = [str(i) for i in range(10)] +
            [chr(c) for c in range(ord('a'), ord('z') + 1)] +
            [chr(c) for c in range(ord('A'), ord('Z') + 1)] +
            [dummy_char]
"""

def str_to_pwd(pwstr):
    return list(map(lambda c: letters.index(c), reversed(pwstr)))
def pwd_to_str(pwd):
    return ''.join(map(lambda i: letters[i], reversed(pwd)))

def add_and_check_range(pwd, digit):
    if digit >= len(pwd):
        return

    pwd[digit] += 1
    if pwd[digit] >= len(letters):
        pwd[digit] = 0
        add_and_check_range(pwd, digit + 1)

def cracker(filename, start, end):
    try:
        curr = str_to_pwd(start)
        last = str_to_pwd(end)
        zip_file = zipfile.ZipFile(filename)

        while curr != last:
            pws = pwd_to_str(curr)
            try:
                # May need to change string encoding if non-ascii characters are used(not tested)
                zip_file.extractall(pwd=pws.encode('ascii'))
                return pws
            except:
                pass

            add_and_check_range(curr, 0)

        return None
    except KeyboardInterrupt:
        return None

def main():
    file = 'a.zip'
    min_length = 1
    max_length = 9

    pool = Pool(None)
    try:
        for length in range(min_length, max_length + 1):
            works = []
            last_pws = None
            for c in letters:
                new_pws = c + '0' * (length - 1)
                if last_pws is not None:
                    works.append((file, last_pws, new_pws))
                last_pws = new_pws

            results = pool.starmap(cracker, works)
            successes = list(filter(lambda result: result is not None, results))
            if len(successes) > 0:
                print("Password found:")
                for pwd in successes:
                    print("> " + pwd)
                break
            else:
                print("Not found at length {}".format(length))
    except KeyboardInterrupt:
        print("Interrupted!")
        return

if __name__ == '__main__':
    main()