| Index: third_party/google-endpoints/Crypto/Cipher/CAST.py
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| diff --git a/third_party/google-endpoints/Crypto/Cipher/CAST.py b/third_party/google-endpoints/Crypto/Cipher/CAST.py
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| new file mode 100644
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| index 0000000000000000000000000000000000000000..f08dab3e0e55c293c12d5d5fed0bd4160f68f6eb
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| --- /dev/null
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| +++ b/third_party/google-endpoints/Crypto/Cipher/CAST.py
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| @@ -0,0 +1,123 @@
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| +# -*- coding: utf-8 -*-
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| +#
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| +# Cipher/CAST.py : CAST
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| +#
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| +# ===================================================================
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| +# The contents of this file are dedicated to the public domain. To
|
| +# the extent that dedication to the public domain is not available,
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| +# everyone is granted a worldwide, perpetual, royalty-free,
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| +# non-exclusive license to exercise all rights associated with the
|
| +# contents of this file for any purpose whatsoever.
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| +# No rights are reserved.
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| +#
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| +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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| +# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
| +# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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| +# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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| +# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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| +# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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| +# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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| +# SOFTWARE.
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| +# ===================================================================
|
| +"""CAST-128 symmetric cipher
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| +
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| +CAST-128_ (or CAST5) is a symmetric block cipher specified in RFC2144_.
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| +
|
| +It has a fixed data block size of 8 bytes. Its key can vary in length
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| +from 40 to 128 bits.
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| +
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| +CAST is deemed to be cryptographically secure, but its usage is not widespread.
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| +Keys of sufficient length should be used to prevent brute force attacks
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| +(128 bits are recommended).
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| +
|
| +As an example, encryption can be done as follows:
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| +
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| + >>> from Crypto.Cipher import CAST
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| + >>> from Crypto import Random
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| + >>>
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| + >>> key = b'Sixteen byte key'
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| + >>> iv = Random.new().read(CAST.block_size)
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| + >>> cipher = CAST.new(key, CAST.MODE_OPENPGP, iv)
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| + >>> plaintext = b'sona si latine loqueris '
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| + >>> msg = cipher.encrypt(plaintext)
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| + >>>
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| + ...
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| + >>> eiv = msg[:CAST.block_size+2]
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| + >>> ciphertext = msg[CAST.block_size+2:]
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| + >>> cipher = CAST.new(key, CAST.MODE_OPENPGP, eiv)
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| + >>> print cipher.decrypt(ciphertext)
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| +
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| +.. _CAST-128: http://en.wikipedia.org/wiki/CAST-128
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| +.. _RFC2144: http://tools.ietf.org/html/rfc2144
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| +
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| +:undocumented: __revision__, __package__
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| +"""
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| +
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| +__revision__ = "$Id$"
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| +
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| +from Crypto.Cipher import blockalgo
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| +from Crypto.Cipher import _CAST
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| +
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| +class CAST128Cipher(blockalgo.BlockAlgo):
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| + """CAST-128 cipher object"""
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| +
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| + def __init__(self, key, *args, **kwargs):
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| + """Initialize a CAST-128 cipher object
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| +
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| + See also `new()` at the module level."""
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| + blockalgo.BlockAlgo.__init__(self, _CAST, key, *args, **kwargs)
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| +
|
| +def new(key, *args, **kwargs):
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| + """Create a new CAST-128 cipher
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| +
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| + :Parameters:
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| + key : byte string
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| + The secret key to use in the symmetric cipher.
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| + Its length may vary from 5 to 16 bytes.
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| + :Keywords:
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| + mode : a *MODE_** constant
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| + The chaining mode to use for encryption or decryption.
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| + Default is `MODE_ECB`.
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| + IV : byte string
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| + The initialization vector to use for encryption or decryption.
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| +
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| + It is ignored for `MODE_ECB` and `MODE_CTR`.
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| +
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| + For `MODE_OPENPGP`, IV must be `block_size` bytes long for encryption
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| + and `block_size` +2 bytes for decryption (in the latter case, it is
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| + actually the *encrypted* IV which was prefixed to the ciphertext).
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| + It is mandatory.
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| +
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| + For all other modes, it must be `block_size` bytes longs. It is optional and
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| + when not present it will be given a default value of all zeroes.
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| + counter : callable
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| + (*Only* `MODE_CTR`). A stateful function that returns the next
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| + *counter block*, which is a byte string of `block_size` bytes.
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| + For better performance, use `Crypto.Util.Counter`.
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| + segment_size : integer
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| + (*Only* `MODE_CFB`).The number of bits the plaintext and ciphertext
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| + are segmented in.
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| + It must be a multiple of 8. If 0 or not specified, it will be assumed to be 8.
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| +
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| + :Return: an `CAST128Cipher` object
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| + """
|
| + return CAST128Cipher(key, *args, **kwargs)
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| +
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| +#: Electronic Code Book (ECB). See `blockalgo.MODE_ECB`.
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| +MODE_ECB = 1
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| +#: Cipher-Block Chaining (CBC). See `blockalgo.MODE_CBC`.
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| +MODE_CBC = 2
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| +#: Cipher FeedBack (CFB). See `blockalgo.MODE_CFB`.
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| +MODE_CFB = 3
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| +#: This mode should not be used.
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| +MODE_PGP = 4
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| +#: Output FeedBack (OFB). See `blockalgo.MODE_OFB`.
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| +MODE_OFB = 5
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| +#: CounTer Mode (CTR). See `blockalgo.MODE_CTR`.
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| +MODE_CTR = 6
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| +#: OpenPGP Mode. See `blockalgo.MODE_OPENPGP`.
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| +MODE_OPENPGP = 7
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| +#: Size of a data block (in bytes)
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| +block_size = 8
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| +#: Size of a key (in bytes)
|
| +key_size = xrange(5,16+1)
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|
|