Helper script to try many different openssl cipher algorithms against a file

filedec.py

#!/usr/bin/env python

import subprocess
import argparse
import os
import sys

def yesno(message_type, default = 'y'):
    if message_type == 'DELETE_FILES_IN_FOLDER':
        question = 'The folder is not empty. Do you want to delete the files in it?'


    valid = {'yes': True, 'y': True, 'no': False, 'n': False}

    if default is None:
        appendix = '[y/n]'
    elif default is 'y':
        appendix = '[Y/n]'
    else:
        appendix = '[y/N]'

    message = "[?] %s %s "%(question, appendix)

    while True:
        sys.stdout.write(message)
        input = raw_input().lower()
        if not default is None and input is '':
            return valid[default]
        elif input in valid:
            return valid[input]
        else:
            sys.stdout.write("[*] Invalid option. Please respond with yes/y or no/n\n")

def getCiphers():
    ciphers = {
        'aes': [],
        'bf': [],
        'camellia': [],
        'cast': [],
        'cast5': [],
        'des': [],
        'desx': [],
        'rc2': [],
        'rc4': [],
        'seed': [],
        'other': []
    }

    tmp = []
    proc = subprocess.Popen(['openssl', 'list-cipher-algorithms'], stdout=subprocess.PIPE)
    tmp = proc.stdout.read().lower().split('\n')[:-1]

    for cipher in tmp:
        try:
            if len(cipher.split(' => ')) is 2:
                cipher = cipher.split(' => ')[1]
            group = cipher.split('-')[:1][0]
            if cipher not in ciphers[group]:
                ciphers[group].append(cipher)
        except:
            if cipher not in ciphers['other']:
                ciphers['other'].append(cipher)

    return ciphers

def help(name=None):
    print """
    Arguments:

    -if <file>                              Encrypted file

    -c, --cipher <cipher[,cipher,...]>      Comma separated cipher list
    -g, --cipher-group <group[,group,...]>  Comma separated cipher group list
    -a, --all-ciphers                       Use all ciphers

    --pass <password>                       Decrypt using this password
    -
    """

def decrypt(infile, cipher, outfile = None, password = None):
    command = ['openssl', 'enc', '-d', '-%s'%(cipher)]
    command.append('-in')
    command.append(infile)

    if not outfile is None:
        command.append('-out')
        command.append(outfile)

    if not password is None:
        command.append('-pass')
        prefix = 'pass' if not os.path.isfile(password) else 'file'
        command.append('%s:%s'%(prefix, password))

    subprocess.Popen(command)

def main(args):

    if not args.list_ciphers is False:
        ciphers = getCiphers()

        print ""
        for group in sorted(ciphers):
            print "[*] Listing ciphers in group '%s'"%(group)
            for cipher in sorted(ciphers[group]):
                print "    %s"%(cipher)
            print ""
        exit(0)

    infile = args.infile
    ciphers = args.cipher.split(',') if not args.cipher is None else None
    cipher_groups = args.cipher_group.split(',') if not args.cipher_group is None else None
    all_ciphers = args.all_ciphers
    password = args.password

    cipher_list = []
    if not ciphers is None:
        cipher_list = ciphers

    elif not cipher_groups is None:
        ciphers = getCiphers()
        for group in cipher_groups:
            for cipher in ciphers[group]:
                cipher_list.append(cipher)

    elif not all_ciphers is None:
        ciphers = getCiphers()
        for group in ciphers:
            for cipher in ciphers[group]:
                cipher_list.append(cipher)

    cipher_list = sorted(cipher_list)


    if not os.path.exists('DECRYPTED_FILES'):
        print "[*] Attempting to create folder 'DECRYPTED_FILES'"
        try:
            os.makedirs('DECRYPTED_FILES')
            print '[+] Folder successfully created\n'
        except:
            print '[-] Unable to create folder. Terminating...'
            exit(1)
    else:
        answer = yesno('DELETE_FILES_IN_FOLDER')
        if answer:
            print '[*] Attempting to clean remove files in folder';
            try:
                folder = 'DECRYPTED_FILES'
                for filename in os.listdir(folder):
                    filepath = os.path.join(folder, filename)
                    try:
                        os.unlink(filepath)
                    except Exception, e:
                        print '[!] %s'%(e)
                print '[+] All files in DECRYPTED_FILES was successfully deleted. Continuing...'
            except:
                print '[-] Unable to delete files in DECRYPTED_FILES. Terminating...'
                exit(1)

    print ""

    print '[*] Decryption process started...'

    for cipher in cipher_list:
        print "[+] Decrypting with cipher '%s'"%(cipher)
        outfile = '%s-%s'%(infile, cipher.replace('-', '_'))
        decrypt(infile, cipher, 'DECRYPTED_FILES/%s'%(outfile), password)

if __name__ == '__main__':

    parser = argparse.ArgumentParser()
    parser.add_argument('-infile', metavar='FILE')
    parser.add_argument('-c', '--cipher', metavar='', help='<cipher[,cipher,...]>')
    parser.add_argument('-g', '--cipher-group', metavar='', help='<group[,group,...]>')
    parser.add_argument('-a', '--all-ciphers', help='Try all ciphers', action='store_true')
    parser.add_argument('--list-ciphers', help='List available ciphers', action='store_true')
    parser.add_argument('--password', help='Password string or filepath')
    parser.add_argument('--pass-is-string', help='Force value of --password to not be treated as filepath if a file has the same name', action='store_true')
    args = parser.parse_args()

    main(args)