[Python-checkins] python/dist/src/Lib hashlib.py, NONE, 1.1 md5.py, NONE, 1.1 sha.py, NONE, 1.1 hmac.py, 1.8, 1.9

[greg@users.sourceforge.net]

Update of /cvsroot/python/python/dist/src/Lib
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv32064/Lib

Modified Files:
	hmac.py 
Added Files:
	hashlib.py md5.py sha.py 
Log Message:
[ sf.net patch # 1121611 ]

A new hashlib module to replace the md5 and sha modules.  It adds
support for additional secure hashes such as SHA-256 and SHA-512.  The
hashlib module uses OpenSSL for fast platform optimized
implementations of algorithms when available.  The old md5 and sha
modules still exist as wrappers around hashlib to preserve backwards
compatibility.



--- NEW FILE: hashlib.py ---
# $Id: hashlib.py,v 1.1 2005/08/21 18:46:00 greg Exp $
#
#  Copyright (C) 2005   Gregory P. Smith (greg at 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')


--- NEW FILE: md5.py ---
# $Id: md5.py,v 1.1 2005/08/21 18:46:00 greg Exp $
#
#  Copyright (C) 2005   Gregory P. Smith (greg at electricrain.com)
#  Licensed to PSF under a Contributor Agreement.

from hashlib import md5
new = md5

blocksize = 1        # legacy value (wrong in any useful sense)
digest_size = 16

--- NEW FILE: sha.py ---
# $Id: sha.py,v 1.1 2005/08/21 18:46:00 greg Exp $
#
#  Copyright (C) 2005   Gregory P. Smith (greg at electricrain.com)
#  Licensed to PSF under a Contributor Agreement.

from hashlib import sha1 as sha
new = sha

blocksize = 1        # legacy value (wrong in any useful sense)
digest_size = 20
digestsize = 20

Index: hmac.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/hmac.py,v
retrieving revision 1.8
retrieving revision 1.9
diff -u -d -r1.8 -r1.9
--- hmac.py	20 Mar 2004 20:11:29 -0000	1.8
+++ hmac.py	21 Aug 2005 18:46:00 -0000	1.9
@@ -28,27 +28,33 @@
 
         key:       key for the keyed hash object.
         msg:       Initial input for the hash, if provided.
-        digestmod: A module supporting PEP 247. Defaults to the md5 module.
+        digestmod: A module supporting PEP 247.  *OR*
+                   A hashlib constructor returning a new hash object.
+                   Defaults to hashlib.md5.
         """
 
         if key is _secret_backdoor_key: # cheap
             return
 
         if digestmod is None:
-            import md5
-            digestmod = md5
+            import hashlib
+            digestmod = hashlib.md5
 
-        self.digestmod = digestmod
-        self.outer = digestmod.new()
-        self.inner = digestmod.new()
-        self.digest_size = digestmod.digest_size
+        if callable(digestmod):
+            self.digest_cons = digestmod
+        else:
+            self.digest_cons = lambda d='': digestmod.new(d)
+
+        self.outer = self.digest_cons()
+        self.inner = self.digest_cons()
+        self.digest_size = self.inner.digest_size
 
         blocksize = 64
         ipad = "\x36" * blocksize
         opad = "\x5C" * blocksize
 
         if len(key) > blocksize:
-            key = digestmod.new(key).digest()
+            key = self.digest_cons(key).digest()
 
         key = key + chr(0) * (blocksize - len(key))
         self.outer.update(_strxor(key, opad))
@@ -70,7 +76,7 @@
         An update to this copy won't affect the original object.
         """
         other = HMAC(_secret_backdoor_key)
-        other.digestmod = self.digestmod
+        other.digest_cons = self.digest_cons
         other.digest_size = self.digest_size
         other.inner = self.inner.copy()
         other.outer = self.outer.copy()