How to hash and crack UNIX passwords in python

Crypt module

I am using the crypt module here, which is a one-way hash function based upon a modified DES algorithm. You can easily adjust the script to crack secure hash algorithms (SHA1, SHA224, SHA256, SHA384, and SHA512 (defined in FIPS 180-2) as well as RSA’s MD5 algorithm ) by using the hashlib  module.

Crypt Overview

import crypt
crypt.crypt("user", "AD")

'AD5Qg2vQhsLRw'

AD is the salt, which is a random two-character string which will be used to perturb the DES algorithm in one of 4096 ways.

The python password cracking script

import crypt
def testPass(hashpass):
    salt = hashpass[0:2]
    dictionary = open('dictionary.txt', 'r') #this is our dictionary file
    for word in dictionary.readlines():
        word = word.strip('\n')
        crypto = crypt.crypt(word,salt)
        if crypto == hashpass:
            print "[+] Password: "+word+"\n"
            return
    print "[-] Password Not Found.\n"
    return

def main():
    hashpass = open('passwords.txt', 'r') #file with hashed password
    for line in hashpass.readlines():
        if ":" in line:
            user = line.split(':')[0]
            hashpass = line.split(':')[1].strip(' ')
            print "[*] Cracking Password For: "+user
            testPass(hashpass)
if __name__ == "__main__":
    main() 

Save the script as cracker.py.
You also need to create a dictionary.txt and password.txt  (with the hashed passwords) file to successfully run the program.

Create a new folder and put the three files into it, afterwards simply run 

python cracker.py

You can download all of the files here: Drive