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diff --git a/Lib/hashlib.py b/Lib/hashlib.py
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+# $Id$
+#
+# Copyright (C) 2005 Gregory P. Smith (greg@electricrain.com)
+# Licensed to PSF under a Contributor Agreement.
+#
+
+__doc__ = """hashlib module - A common interface to many hash functions.
+
+new(name, string='') - returns a new hash object implementing the
+ given hash function; initializing the hash
+ using the given string data.
+
+Named constructor functions are also available, these are much faster
+than using new():
+
+md5(), sha1(), sha224(), sha256(), sha384(), and sha512()
+
+More algorithms may be available on your platform but the above are
+guaranteed to exist.
+
+Choose your hash function wisely. Some have known weaknesses.
+sha384 and sha512 will be slow on 32 bit platforms.
+"""
+
+
+def __get_builtin_constructor(name):
+ if name in ('SHA1', 'sha1'):
+ import _sha
+ return _sha.new
+ elif name in ('MD5', 'md5'):
+ import _md5
+ return _md5.new
+ elif name in ('SHA256', 'sha256', 'SHA224', 'sha224'):
+ import _sha256
+ bs = name[3:]
+ if bs == '256':
+ return _sha256.sha256
+ elif bs == '224':
+ return _sha256.sha224
+ elif name in ('SHA512', 'sha512', 'SHA384', 'sha384'):
+ import _sha512
+ bs = name[3:]
+ if bs == '512':
+ return _sha512.sha512
+ elif bs == '384':
+ return _sha512.sha384
+
+ raise ValueError, "unsupported hash type"
+
+
+def __py_new(name, string=''):
+ """new(name, string='') - Return a new hashing object using the named algorithm;
+ optionally initialized with a string.
+ """
+ return __get_builtin_constructor(name)(string)
+
+
+def __hash_new(name, string=''):
+ """new(name, string='') - Return a new hashing object using the named algorithm;
+ optionally initialized with a string.
+ """
+ try:
+ return _hashlib.new(name, string)
+ except ValueError:
+ # If the _hashlib module (OpenSSL) doesn't support the named
+ # hash, try using our builtin implementations.
+ # This allows for SHA224/256 and SHA384/512 support even though
+ # the OpenSSL library prior to 0.9.8 doesn't provide them.
+ return __get_builtin_constructor(name)(string)
+
+
+try:
+ import _hashlib
+ # use the wrapper of the C implementation
+ new = __hash_new
+
+ for opensslFuncName in filter(lambda n: n.startswith('openssl_'), dir(_hashlib)):
+ funcName = opensslFuncName[len('openssl_'):]
+ try:
+ # try them all, some may not work due to the OpenSSL
+ # version not supporting that algorithm.
+ f = getattr(_hashlib, opensslFuncName)
+ f()
+ # Use the C function directly (very fast)
+ exec funcName + ' = f'
+ except ValueError:
+ try:
+ # Use the builtin implementation directly (fast)
+ exec funcName + ' = __get_builtin_constructor(funcName)'
+ except ValueError:
+ # this one has no builtin implementation, don't define it
+ pass
+ # clean up our locals
+ del f
+ del opensslFuncName
+ del funcName
+
+except ImportError:
+ # We don't have the _hashlib OpenSSL module?
+ # use the built in legacy interfaces via a wrapper function
+ new = __py_new
+
+ # lookup the C function to use directly for the named constructors
+ md5 = __get_builtin_constructor('md5')
+ sha1 = __get_builtin_constructor('sha1')
+ sha224 = __get_builtin_constructor('sha224')
+ sha256 = __get_builtin_constructor('sha256')
+ sha384 = __get_builtin_constructor('sha384')
+ sha512 = __get_builtin_constructor('sha512')
+