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Diffstat (limited to 'frozen_deps/Crypto/Cipher/CAST.py')
| -rw-r--r-- | frozen_deps/Crypto/Cipher/CAST.py | 123 |
1 files changed, 0 insertions, 123 deletions
diff --git a/frozen_deps/Crypto/Cipher/CAST.py b/frozen_deps/Crypto/Cipher/CAST.py deleted file mode 100644 index 89543b2..0000000 --- a/frozen_deps/Crypto/Cipher/CAST.py +++ /dev/null @@ -1,123 +0,0 @@ -# -*- coding: utf-8 -*- -# -# Cipher/CAST.py : CAST -# -# =================================================================== -# The contents of this file are dedicated to the public domain. To -# the extent that dedication to the public domain is not available, -# everyone is granted a worldwide, perpetual, royalty-free, -# non-exclusive license to exercise all rights associated with the -# contents of this file for any purpose whatsoever. -# No rights are reserved. -# -# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, -# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF -# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND -# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS -# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN -# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN -# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE -# SOFTWARE. -# =================================================================== -"""CAST-128 symmetric cipher - -CAST-128_ (or CAST5) is a symmetric block cipher specified in RFC2144_. - -It has a fixed data block size of 8 bytes. Its key can vary in length -from 40 to 128 bits. - -CAST is deemed to be cryptographically secure, but its usage is not widespread. -Keys of sufficient length should be used to prevent brute force attacks -(128 bits are recommended). - -As an example, encryption can be done as follows: - - >>> from Crypto.Cipher import CAST - >>> from Crypto import Random - >>> - >>> key = b'Sixteen byte key' - >>> iv = Random.new().read(CAST.block_size) - >>> cipher = CAST.new(key, CAST.MODE_OPENPGP, iv) - >>> plaintext = b'sona si latine loqueris ' - >>> msg = cipher.encrypt(plaintext) - >>> - ... - >>> eiv = msg[:CAST.block_size+2] - >>> ciphertext = msg[CAST.block_size+2:] - >>> cipher = CAST.new(key, CAST.MODE_OPENPGP, eiv) - >>> print cipher.decrypt(ciphertext) - -.. _CAST-128: http://en.wikipedia.org/wiki/CAST-128 -.. _RFC2144: http://tools.ietf.org/html/rfc2144 - -:undocumented: __revision__, __package__ -""" - -__revision__ = "$Id$" - -from Crypto.Cipher import blockalgo -from Crypto.Cipher import _CAST - -class CAST128Cipher(blockalgo.BlockAlgo): - """CAST-128 cipher object""" - - def __init__(self, key, *args, **kwargs): - """Initialize a CAST-128 cipher object - - See also `new()` at the module level.""" - blockalgo.BlockAlgo.__init__(self, _CAST, key, *args, **kwargs) - -def new(key, *args, **kwargs): - """Create a new CAST-128 cipher - - :Parameters: - key : byte string - The secret key to use in the symmetric cipher. - Its length may vary from 5 to 16 bytes. - :Keywords: - mode : a *MODE_** constant - The chaining mode to use for encryption or decryption. - Default is `MODE_ECB`. - IV : byte string - The initialization vector to use for encryption or decryption. - - It is ignored for `MODE_ECB` and `MODE_CTR`. - - For `MODE_OPENPGP`, IV must be `block_size` bytes long for encryption - and `block_size` +2 bytes for decryption (in the latter case, it is - actually the *encrypted* IV which was prefixed to the ciphertext). - It is mandatory. - - For all other modes, it must be `block_size` bytes longs. It is optional and - when not present it will be given a default value of all zeroes. - counter : callable - (*Only* `MODE_CTR`). A stateful function that returns the next - *counter block*, which is a byte string of `block_size` bytes. - For better performance, use `Crypto.Util.Counter`. - segment_size : integer - (*Only* `MODE_CFB`).The number of bits the plaintext and ciphertext - are segmented in. - It must be a multiple of 8. If 0 or not specified, it will be assumed to be 8. - - :Return: an `CAST128Cipher` object - """ - return CAST128Cipher(key, *args, **kwargs) - -#: Electronic Code Book (ECB). See `blockalgo.MODE_ECB`. -MODE_ECB = 1 -#: Cipher-Block Chaining (CBC). See `blockalgo.MODE_CBC`. -MODE_CBC = 2 -#: Cipher FeedBack (CFB). See `blockalgo.MODE_CFB`. -MODE_CFB = 3 -#: This mode should not be used. -MODE_PGP = 4 -#: Output FeedBack (OFB). See `blockalgo.MODE_OFB`. -MODE_OFB = 5 -#: CounTer Mode (CTR). See `blockalgo.MODE_CTR`. -MODE_CTR = 6 -#: OpenPGP Mode. See `blockalgo.MODE_OPENPGP`. -MODE_OPENPGP = 7 -#: Size of a data block (in bytes) -block_size = 8 -#: Size of a key (in bytes) -key_size = range(5,16+1) |