cli.py

#!/usr/bin/env python3

import sys
import argparse

from manytime import many_time_pad_attack


def main() -> None:
    """
    Main entry point for CLI program
    """
    parser = argparse.ArgumentParser(description='Break One-Time Pad Encryption with key reuse')
    parser.add_argument('file', type=str, help='file containing hexadecimal ciphertexts, delimited by new lines')
    parser.add_argument('-o', type=str, dest='output_file', default='result.json', help='filename to export decryptions to')
    args = parser.parse_args()

    with open(args.file, 'r') as f:
        ciphertexts = [line.rstrip() for line in f]

    try:
        ciphertexts = list(map(bytearray.fromhex, ciphertexts))
    except ValueError as error:
        sys.exit("Invalid hexadecimal: {error}")

    many_time_pad_attack(ciphertexts, args.output_file)