code.kerkeslager.com Git - sandbox/blob - cryptopals-python/cryptopals.py

   1 import codecs
   2 import unittest
   3
   4 def base64_from_hex(_hex):
   5     return codecs.encode(bytes.fromhex(_hex), 'base64').decode('utf-8')
   6
   7 def hex_xor(hex0, hex1):
   8     assert len(hex0) == len(hex1)
   9     bytes0 = bytes.fromhex(hex0)
  10     bytes1 = bytes.fromhex(hex1)
  11     xored_bytes = bytes(byte0 ^ byte1 for byte0, byte1 in zip(bytes0, bytes1))
  12     return codecs.encode(xored_bytes, 'hex').decode('utf-8')
  13
  14 class Set1Challenge1Tests(unittest.TestCase):
  15     def test_converts_hex_to_base64(self):
  16         expected = 'SSdtIGtpbGxpbmcgeW91ciBicmFpbiBsaWtlIGEgcG9pc29ub3VzIG11c2hyb29t\n'
  17         actual = base64_from_hex('49276d206b696c6c696e6720796f757220627261696e206c696b65206120706f69736f6e6f7573206d757368726f6f6d')
  18         self.assertEqual(expected, actual)
  19
  20 class Set1Challenge2Tests(unittest.TestCase):
  21     def test_xors_hex_strings(self):
  22         hex0 = '1c0111001f010100061a024b53535009181c'
  23         hex1 = '686974207468652062756c6c277320657965'
  24
  25         expected = '746865206b696420646f6e277420706c6179'
  26         actual = hex_xor(hex0, hex1)
  27
  28         self.assertEqual(expected, actual)
  29
  30 if __name__ == '__main__':
  31     unittest.main()