Generate AS400 password. MIT License

genas400pass.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# Copyright © 2016 Taylor C. Richberger <taywee@gmx.com>
# This code is released under the license described in the LICENSE file

import argparse
import random
import string

STARTSPECIAL = '$@#'
SPECIAL = STARTSPECIAL + '_'

def rangeint(start, end):
    rng = range(start, end + 1)
    def checkrange(value):
        ivalue = int(value)
        if ivalue not in rng:
            raise argparse.ArgumentError('value {} not in range {}'.format(ivalue, rng))
        return ivalue
    return checkrange

def main():
    parser = argparse.ArgumentParser(description='Generate random passwords for as400 users')
    parser.add_argument('-d', '--digits', help='The minimum number of digits (default: %(default)s)', type=rangeint(0, 10), default=1)
    parser.add_argument('-l', '--letters', help='The minimum number of letters (default: %(default)s)', type=rangeint(0, 10), default=1)
    parser.add_argument('-s', '--special', help='The minimum number of chars (default: %(default)s)', type=rangeint(0, 10), default=1)
    parser.add_argument('-a', '--ambiguous', help='Allow ambiguous characters (1, I, 0, O)', action='store_true')
    parser.add_argument('length',
        help='The length of the password (default: %(default)s).  This will '
        'be exceeded if it is shorter than necessary for  the mandatory '
        'minimum characters', type=rangeint(1, 10), nargs='?', default=10)
    args = parser.parse_args()

    if args.ambiguous:
        letters = string.ascii_uppercase
        digits = string.digits
    else:
        letters = string.ascii_uppercase.translate({ord(c): None for c in 'OI'})
        digits = string.digits.translate({ord(c): None for c in '01'})

    if args.special > 0:
        firstchar = letters + STARTSPECIAL
    else:
        firstchar = letters

    all = ''.join((letters, digits, SPECIAL))

    chars = ([random.choice(digits) for i in range(args.digits)]
        + [random.choice(letters) for i in range(args.letters)]
        + [random.choice(SPECIAL) for i in range(args.special)])

    # Get up to one less than the length
    while len(chars) < (args.length - 1):
        chars.append(random.choice(all))

    random.shuffle(chars)

    # First char must not be numeric or underline character
    chars.insert(0, random.choice(firstchar))
    print(''.join(chars))

if __name__ == '__main__':
    main()

Needs two more option switches:

1. take a list of special chars
2. generate mixed case