Simple /etc/shadow Cracker - linux

Question

I'm trying to get this shadow file cracker working but I keep getting a TypeError: integer required.
I'm sure its the way I'm using the bytearray function. I've tried creating a new object with bytearray for the "word" and the "salt" however to no avail. So then I tried passing the bytearray constructor to the pbkdf2 function and still nothing. I will post the code:
#!/usr/bin/python
# -*- coding: utf-8 -*-
import hashlib, binascii
import os,sys
import crypt
import codecs
from datetime import datetime,timedelta
import argparse
today = datetime.today()
# Takes in user and the encrypted passwords and does a simple
# Brute Force Attack useing the '==' operator. SHA* is defined by
# a number b/w $, the char's b/w the next $ marker would be the
# rounds, then the salt, and after that the hashed password.
# object.split("some symbol or char")[#], where # is the
# location/index within the list
def testPass(cryptPass,user):
digest = hashlib.sha512
dicFile = open ('Dictionary.txt','r')
ctype = cryptPass.split("$")[1]
if ctype == '6':
print "[+] Hash type SHA-512 detected ..."
print "[+] Be patien ..."
rounds = cryptPass.split("$")[2].strip('rounds=')
salt = cryptPass.split("$")[3]
print "[DEBUG]: " + rounds
print "[DEBUG]: " + salt
# insalt = "$" + ctype + "$" + salt + "$" << COMMENTED THIS OUT
for word in dicFile.readlines():
word = word.strip('\n')
print "[DEBUG]: " + word
cryptWord = hashlib.pbkdf2_hmac(digest().name,bytearray(word, 'utf-8'),bytearray(salt, 'utf-8'), rounds)
if (cryptWord == cryptPass):
time = time = str(datetime.today() - today)
print "[+] Found password for the user: " + user + " ====> " + word + " Time: "+time+"\n"
return
else:
print "Nothing found, bye!!"
exit
# argparse is used in main to parse arguments pass by the user.
# Path to shadow file is required as a argument.
def main():
parse = argparse.ArgumentParser(description='A simple brute force /etc/shadow .')
parse.add_argument('-f', action='store', dest='path', help='Path to shadow file, example: \'/etc/shadow\'')
argus=parse.parse_args()
if argus.path == None:
parse.print_help()
exit
else:
passFile = open (argus.path,'r', 1) # ADDING A 1 INDICATES A BUFFER OF A
for line in passFile.readlines(): # SINGLE LINE '1<=INDICATES
line = line.replace("\n","").split(":") # EXACT BUFFER SIZE
if not line[1] in [ 'x', '*','!' ]:
user = line[0]
cryptPass = line[1]
testPass(cryptPass,user)
if __name__=="__main__":
main()
OUTPUT:
[+] Hash type SHA-512 detected ...
[+] Be patien ...
[DEBUG]: 65536
[DEBUG]: A9UiC2ng
[DEBUG]: hellocat
Traceback (most recent call last):
File "ShadowFileCracker.py", line 63, in <module>
main()
File "ShadowFileCracker.py", line 60, in main
testPass(cryptPass,user)
File "ShadowFileCracker.py", line 34, in testPass
cryptWord = hashlib.pbkdf2_hmac(digest().name,bytearray(word, 'utf-8'),bytearray(salt, 'utf-8'), rounds)
TypeError: an integer is required

Answer 1

The rounds variable needs to be an integer, not a string. The correct line should be:
rounds = int(cryptPass.split("$")[2].strip('rounds='))
Also, strip() might not be the best method for removing the leading "rounds=". It will work, but it strips a set of characters and not a string. A slightly better method would be:
rounds = int(cryptPass.split("$")[2].split("=")[1])