Create a salted SHA512 password hash for use with Dovecot, updated for python 3

SSHA512_gen.py

#!/usr/bin/python

import os
import hashlib
import getpass
import base64

password1 = None
password2 = None

# Read the password
while password1 != password2 or password1 == None:
  password1 = getpass.getpass()
  password2 = getpass.getpass("Confirm password: ")
  if (password1 != password2):
    print("\nPassword mismatch, try again.")

# Generate a 5 byte random salt
salt = os.urandom(5)

# Hash our password + salt
sha = hashlib.sha512()
sha.update(password1.encode('utf-8'))
sha.update(salt)
ssha512 = base64.b64encode('{}{}'.format(sha.digest(), salt).encode('utf-8'))

# Print it out with a prefix for Dovecot
print("\n{{SSHA512}}{}".format(ssha512))