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Viewing changes to attic/crypto.py

  • Committer: Package Import Robot
  • Author(s): Clint Adams
  • Date: 2013-11-25 09:06:12 UTC
  • mfrom: (1.1.1)
  • Revision ID: package-import@ubuntu.com-20131125090612-hp1yitu1qnpbuaq7
Tags: 0.8.1-1
* New upstream version.
* Bump to Standards-Version 3.9.5.

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attic/crypto.py
 
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"""A thin ctypes based wrapper for OpenSSL 1.0
 
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"""
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import sys
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from ctypes import cdll, c_char_p, c_int, c_uint, c_void_p, POINTER, create_string_buffer
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from ctypes.util import find_library
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# Default libcrypto on OS X is too old, try the brew version
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if not hasattr(libcrypto, 'PKCS5_PBKDF2_HMAC') and sys.platform == 'darwin':
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    libcrypto = cdll.LoadLibrary('/usr/local/opt/openssl/lib/libcrypto.dylib')
 
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# Default libcrypto on FreeBSD is too old, try the ports version
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if not hasattr(libcrypto, 'PKCS5_PBKDF2_HMAC') and sys.platform.startswith('freebsd'):
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    libcrypto = cdll.LoadLibrary('/usr/local/lib/libcrypto.so')
 
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libcrypto.PKCS5_PBKDF2_HMAC.argtypes = (c_char_p, c_int, c_char_p, c_int, c_int, c_void_p, c_int, c_char_p)
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libcrypto.EVP_sha256.restype = c_void_p
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libcrypto.AES_set_encrypt_key.argtypes = (c_char_p, c_int, c_char_p)
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libcrypto.AES_ctr128_encrypt.argtypes = (c_char_p, c_char_p, c_int, c_char_p, c_char_p, c_char_p, POINTER(c_uint))
 
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libcrypto.RAND_bytes.argtypes = (c_char_p, c_int)
 
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libcrypto.RAND_bytes.restype = c_int
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_int = struct.Struct('>I')
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_long = struct.Struct('>Q')
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long_to_bytes = lambda x: _long.pack(x)
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def num_aes_blocks(length):
 
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    """Return the number of AES blocks required to encrypt/decrypt *length* bytes of data
 
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    """
 
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    return (length + 15) // 16
 
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def pbkdf2_sha256(password, salt, iterations, size):
 
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    """Password based key derivation function 2 (RFC2898)
 
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    """
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    key = create_string_buffer(size)
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    rv = libcrypto.PKCS5_PBKDF2_HMAC(password, len(password), salt, len(salt), iterations, libcrypto.EVP_sha256(), size, key)
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    if not rv:
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    """Return n cryptographically strong pseudo-random bytes
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    """
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    buf = create_string_buffer(n)
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    if not libcrypto.RAND_bytes(buf, n):
 
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    if libcrypto.RAND_bytes(buf, n) < 1:
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        raise Exception('RAND_bytes failed')
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    return buf.raw
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class AES:
 
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    """A thin wrapper around the OpenSSL AES CTR_MODE cipher
 
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    """
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    def __init__(self, key, iv=None):
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        self.key = create_string_buffer(2000)
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        self.iv = create_string_buffer(16)