| 0,0 → 1,80 |
|---|
| from blockcipher import * |
| import pyDes |
| |
| def new(key,mode=MODE_ECB,IV=None,counter=None,segment_size=None): |
| """Create a DES-EDE3 or DES-EDE2 cipher object |
| |
| wrapper for pure python 3DES implementation pyDes.py |
| |
| key = raw string containing the 2/3 keys |
| - DES-EDE2: supply 2 keys as 1 single concatenated 16byte key= key1|key2 |
| - DES-EDE3: supply 3 keys as 1 single concatenated 24byte key= key1|key2|key3 |
| 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 python_DES3 |
| |
| CBC TDES-EDE3 EXAMPLE: (using test vectors from http://csrc.nist.gov/groups/STM/cavp/documents/des/DESMMT.pdf) |
| ------------ |
| >>> key = ('37ae5ebf46dff2dc0754b94f31cbb3855e7fd36dc870bfae').decode('hex') |
| >>> IV = ('3d1de3cc132e3b65').decode('hex') |
| >>> cipher = python_DES3.new(key, python_DES3.MODE_CBC, IV) |
| >>> ciphertext = cipher.encrypt(('84401f78fe6c10876d8ea23094ea5309').decode('hex')) |
| >>> (ciphertext).encode('hex') |
| '7b1f7c7e3b1c948ebd04a75ffba7d2f5' |
| >>> decipher = python_DES3.new(key, python_DES3.MODE_CBC, IV) |
| >>> plaintext = decipher.decrypt(ciphertext) |
| >>> (plaintext).encode('hex') |
| '84401f78fe6c10876d8ea23094ea5309' |
| |
| CMAC TDES-EDE3 EXAMPLE: |
| ------------- |
| testvector: http://csrc.nist.gov/publications/nistpubs/800-38B/Updated_CMAC_Examples.pdf |
| |
| >>> key = '8aa83bf8cbda10620bc1bf19fbb6cd58bc313d4a371ca8b5'.decode('hex') |
| >>> plaintext = '6bc1bee22e409f96e93d7e117393172aae2d8a57'.decode('hex') |
| >>> cipher = python_DES3.new(key, python_DES3.MODE_CMAC) |
| >>> cipher.encrypt(plaintext).encode('hex') |
| '743ddbe0ce2dc2ed' |
| |
| CMAC TDES-EDE2 EXAMPLE: |
| ----------------------- |
| testvector: http://csrc.nist.gov/groups/STM/cavp/documents/mac/cmactestvectors.zip |
| |
| >>> key1 = "5104f2c76180c1d3".decode('hex') |
| >>> key2 = "b9df763e31ada716".decode('hex') |
| >>> key = key1 + key2 |
| >>> plaintext = 'a6866be2fa6678f264a19c4474968e3f4eec24f5086d'.decode('hex') |
| >>> cipher = python_DES3.new(key, python_DES3.MODE_CMAC) |
| >>> cipher.encrypt(plaintext).encode('hex') |
| '32e7758f3f614dbf'""" |
| return python_DES3(key,mode,IV,counter,segment_size) |
| |
| class python_DES3(BlockCipher): |
| key_error_message = "Key should be 128 or 192 bits" |
| |
| def __init__(self,key,mode,IV,counter,segment_size): |
| cipher_module = pyDes.triple_des |
| self.blocksize = 8 |
| BlockCipher.__init__(self,key,mode,IV,counter,cipher_module,segment_size) |
| |
| def keylen_valid(self,key): |
| return len(key) in (16,24) |
| |
| def _test(): |
| import doctest |
| doctest.testmod() |
| |
| if __name__ == "__main__": |
| _test() |