| 0,0 → 1,57 |
|---|
| from blockcipher import * |
| import Crypto.Cipher.CAST |
| |
| def new(key,mode=MODE_ECB,IV=None,counter=None,segment_size=None): |
| """Create a new cipher object |
| |
| CAST using pycrypto for algo and pycryptoplus for ciphermode |
| |
| key = raw string containing the keys |
| mode = python_AES.MODE_ECB/CBC/CFB/OFB/CTR/CMAC, default is ECB |
| IV = IV as a raw string, default is "all zero" IV |
| -> only needed for CBC mode |
| counter = counter object (CryptoPlus.Util.util.Counter) |
| -> only needed for CTR mode |
| segment_size = amount of bits to use from the keystream in each chain part |
| -> supported values: multiple of 8 between 8 and the blocksize |
| of the cipher (only per byte access possible), default is 8 |
| -> only needed for CFB mode |
| |
| EXAMPLES: |
| ********** |
| IMPORTING: |
| ----------- |
| >>> from CryptoPlus.Cipher import CAST |
| |
| ECB example: http://www.rfc-editor.org/rfc/rfc2144.txt |
| ------------- |
| 128 bit key |
| |
| >>> key = "0123456712345678234567893456789A".decode('hex') |
| >>> plaintext = "0123456789ABCDEF".decode('hex') |
| >>> cipher = CAST.new(key,CAST.MODE_ECB,) |
| >>> cipher.encrypt(plaintext).encode('hex') |
| '238b4fe5847e44b2' |
| |
| 40 bit key |
| >>> from CryptoPlus.Cipher import CAST |
| >>> key = "0123456712".decode('hex') |
| >>> plaintext = "0123456789ABCDEF".decode('hex') |
| >>> cipher = CAST.new(key,CAST.MODE_ECB,) |
| >>> cipher.encrypt(plaintext).encode('hex').upper() |
| '7AC816D16E9B302E' |
| """ |
| return CAST(key,mode,IV,counter,segment_size) |
| |
| class CAST(BlockCipher): |
| def __init__(self,key,mode,IV,counter,segment_size): |
| cipher_module = Crypto.Cipher.CAST.new |
| self.blocksize = 8 |
| BlockCipher.__init__(self,key,mode,IV,counter,cipher_module,segment_size) |
| |
| def _test(): |
| import doctest |
| doctest.testmod() |
| |
| if __name__ == "__main__": |
| _test() |