unix-crypt-sha512

README.md

unix-crypt-sha512

command to make SHA512 password hash from stdin as crypt(3).

Options

• -s: specifying salt.
• -c: checking specified hash is valid for stdin.

Dependency

• unix-crypt: unix-crypt-sha512.rb depends on it. To install, do gen install unix-crypt.

unix-crypt-sha512.py

#! /usr/bin/env python3.7

import sys
import crypt
import re

def check(pass_hash):
    m = re.match(r'^\$6\$(.+)\$.{86}$', pass_hash)
    if not m:
        print("invalid hash: %s" % pass_hash, file=sys.stderr)
        exit(1)
    salt = m.group(1)
    if crypt.crypt(sys.stdin.read(), "$6$%s" % salt) == pass_hash:
        print("True", file=sys.stderr)
        exit(0)
    else:
        print("False", file=sys.stderr)
        exit(1)

def main(argv):
    if len(argv) == 3:
        if argv[1] == '-s':
            print(crypt.crypt(sys.stdin.read(), '$6$%s' % argv[2]))
        elif argv[1] == '-c':
            check(argv[2])
    elif len(argv) == 1:
        print(crypt.crypt(sys.stdin.read()))
    else:
        print("option can be only '-s' or '-c'", file=sys.stderr)
        exit(1)

if __name__ == '__main__':
    assert crypt.methods[0] == crypt.METHOD_SHA512, \
        'METHOD_SHA512 cannot be used.'
    main(sys.argv)

unix-crypt-sha512.rb

#! /usr/bin/env ruby

require 'unix_crypt'

def check(pass_hash)
  m = /^\$6\$(.+)\$.{86}$/.match(pass_hash)
  if not m then
    puts ("invalid hash: %s" % pass_hash)
    exit 1
  end
  salt = m.captures[0]
  if UnixCrypt::SHA512.build($stdin.read, salt) == pass_hash then
    STDERR.puts "True"
    exit 0
  else
    STDERR.puts "False"
    exit 1
  end
end

def main(argv)
  if argv.length == 0 then
    pass = UnixCrypt::SHA512.build($stdin.read)
    puts pass
  elsif argv.length == 2 then
    if argv[0] == "-s" then
      salt = argv[1]
      pass = UnixCrypt::SHA512.build($stdin.read, salt)
      puts pass
    elsif argv[0] == "-c" then
      check(argv[1])
    else
      STDERR.puts "option can be only '-s' or '-c'"
      exit 1
    end
  else
    STDERR.puts "invalid numbers of args are passed."
    exit 1
  end
end

if __FILE__ == $0
  main ARGV
end