mirror of
https://github.com/python/cpython.git
synced 2024-12-02 06:14:49 +08:00
110 lines
3.5 KiB
Python
110 lines
3.5 KiB
Python
# $Id$
|
|
#
|
|
# 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')
|