src/Cipher/DES3.py

   1 from blockcipher import *
   2 import Crypto.Cipher.DES3
   3
   4 def new(key,mode=MODE_ECB,IV=None,counter=None):
   5     """Create a new cipher object
   6
   7     DES using pycrypto for algo and pycryptoplus for ciphermode
   8
   9     new(key,mode=MODE_ECB,IV=None,counter=None):
  10         key = raw string containing the 2/3 keys
  11             - DES-EDE2: supply 2 keys as 1 single concatenated 16byte key= key1|key2
  12             - DES-EDE3: supply 3 keys as 1 single concatenated 24byte key= key1|key2|key3
  13         mode = python_AES.MODE_ECB/CBC/CFB/OFB/CTR/CMAC, default is ECB
  14         IV = IV as a raw string
  15             -> only needed for CBC mode
  16         counter = counter object (CryptoPlus.Util.util.Counter)
  17             -> only needed for CTR mode
  18
  19
  20     CBC TDES-EDE3 EXAMPLE: (using test vectors from http://csrc.nist.gov/groups/STM/cavp/documents/des/DESMMT.pdf)
  21     ------------
  22     >>> import DES3
  23     >>> from binascii import hexlify, unhexlify
  24     >>> key = unhexlify('37ae5ebf46dff2dc0754b94f31cbb3855e7fd36dc870bfae')
  25     >>> IV = unhexlify('3d1de3cc132e3b65')
  26     >>> cipher = DES3.new(key, DES3.MODE_CBC, IV)
  27     >>> ciphertext = cipher.encrypt(unhexlify('84401f78fe6c10876d8ea23094ea5309'))
  28     >>> hexlify(ciphertext)
  29     '7b1f7c7e3b1c948ebd04a75ffba7d2f5'
  30     >>> decipher = DES3.new(key, DES3.MODE_CBC, IV)
  31     >>> plaintext = decipher.decrypt(ciphertext)
  32     >>> hexlify(plaintext)
  33     '84401f78fe6c10876d8ea23094ea5309'
  34
  35     CMAC TDES-EDE3 EXAMPLE: (http://csrc.nist.gov/publications/nistpubs/800-38B/Updated_CMAC_Examples.pdf)
  36     -------------
  37     >>> key = '8aa83bf8cbda10620bc1bf19fbb6cd58bc313d4a371ca8b5'.decode('hex')
  38     >>> plaintext = '6bc1bee22e409f96e93d7e117393172aae2d8a57'.decode('hex')
  39     >>> cipher = DES3.new(key, DES3.MODE_CMAC)
  40     >>> cipher.encrypt(plaintext).encode('hex')
  41     '743ddbe0ce2dc2ed'
  42
  43     CMAC TDES-EDE2 EXAMPLE:
  44     -----------------------
  45     testvector: http://csrc.nist.gov/groups/STM/cavp/documents/mac/cmactestvectors.zip
  46
  47     >>> key1 = "5104f2c76180c1d3".decode('hex')
  48     >>> key2 = "b9df763e31ada716".decode('hex')
  49     >>> key = key1 + key2
  50     >>> plaintext = 'a6866be2fa6678f264a19c4474968e3f4eec24f5086d'.decode('hex')
  51     >>> cipher = DES3.new(key, DES3.MODE_CMAC)
  52     >>> cipher.encrypt(plaintext).encode('hex')
  53     '32e7758f3f614dbf'
  54     """
  55     return DES3(key,mode,IV,counter)
  56
  57 class DES3(BlockCipher):
  58     def __init__(self,key,mode,IV,counter):
  59         self.cipher = Crypto.Cipher.DES3.new(key)
  60         self.blocksize = Crypto.Cipher.DES3.block_size
  61         BlockCipher.__init__(self,key,mode,IV,counter)
  62
  63 def _test():
  64     import doctest
  65     doctest.testmod()
  66
  67 if __name__ == "__main__":
  68     _test()