simple password tools - random password, password hashing with various algorithms, verify password hash

password.py

#!/usr/bin/env python
# coding=utf-8

import argparse
import getpass
import os
import random
import string

from passlib.hash import (bcrypt, des_crypt, md5_crypt, sha1_crypt,
                          sha256_crypt, sha512_crypt)


def random_password():
    '''
    generate random password which satisfies minimum 2 digits, 2 special chars and 20 chars long.
    '''
    random.seed = (os.urandom(16))
    alphabets = ''.join(random.choice(string.ascii_letters) for _ in range(16))
    digits = ''.join(random.choice(string.digits) for _ in range(2))
    special_chars = ''.join(random.choice('!@#$%^&*(),.') for _ in range(2))
    passwd_char_list = list(alphabets+digits+special_chars)
    for _ in range(1024):
        random.shuffle(passwd_char_list)
    return ''.join(passwd_char_list)


def des_password(password):
    return des_crypt.hash(password)


def bcrypt_password(password):
    return bcrypt.using(rounds=10).hash(password)


def md5_password(password):
    return md5_crypt.hash(password, salt_size=4)


def sha1_password(password):
    return sha1_crypt.hash(password, rounds=random.randrange(20000, 30000))


def sha256_password(password):
    return sha256_crypt.hash(password, rounds=5000)


def sha512_password(password):
    return sha512_crypt.hash(password, rounds=5000)


def encrypt(alg):
    crypt_funcs = {
        'des': des_password,
        'bcrypt': bcrypt_password,
        'md5': md5_password,
        'sha1': sha1_password,
        'sha256': sha256_password,
        'sha512': sha512_password
    }
    password = getpass.getpass("Password:")
    encrypted = crypt_funcs[alg](password)
    return encrypted


def verify_password(encrypted):
    password = getpass.getpass("Password:")

    try:
        return ('DES', des_crypt.verify(password, encrypted))
    except:
        pass

    try:
        return ('BCRYPT', bcrypt.verify(password, encrypted))
    except:
        pass

    try:
        return ('MD5', md5_crypt.verify(password, encrypted))
    except:
        pass

    try:
        return ('SHA1', sha1_crypt.verify(password, encrypted))
    except:
        pass

    try:
        return ('SHA256', sha256_crypt.verify(password, encrypted))
    except:
        pass

    try:
        return ('SHA512', sha512_crypt.verify(password, encrypted))
    except:
        pass

    print("Not a valid encrypted hash value or unsupported algorithm.")
    return False

if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='password utility')

    group = parser.add_mutually_exclusive_group()
    group.add_argument("-a", "--algorithm", choices=['des', 'bcrypt', 'md5', 'sha1', 'sha256', 'sha512'],
                       help='encryption algorithm')
    group.add_argument("-v", "--verify", nargs=1,
                       metavar='hash', help='Verify encrypted hash value.')
    group.add_argument("-g", "--generate", action='store_true',
                       help='Generate random password.')

    args = parser.parse_args()

    if args.algorithm:
        print(encrypt(args.algorithm))
    elif args.verify:
        print(verify_password(args.verify[0]))
    elif args.generate:
        print(random_password() + '\t(Note: this is not an encrypted hash.)')
    else:
        parser.print_help()