+
−# -*- coding: UTF-8 -*-
+
−# Copyright (c) 2010 - 2011, Pascal Volk
+
−# See COPYING for distribution information.
+
−
+
−"""
+
−    VirtualMailManager.pycompat.hashlib
+
−
+
−    VirtualMailManager's minimal hashlib emulation for Python 2.4
+
−
+
−    hashlib.md5(...), hashlib.sha1(...), hashlib.new('md5', ...) and
+
−    hashlib.new('sha1', ...) will work always.
+
−
+
−    When the PyCrypto module <http://www.pycrypto.org/> could be found in
+
−    sys.path hashlib.new('md4', ...) will also work.
+
−
+
−    With PyCrypto >= 2.1.0alpha1 hashlib.new('sha256', ...) and
+
−    hashlib.sha256(...) becomes functional.
+
−"""
+
−
+
−
+
−import md5 as _md5
+
−import sha as _sha1
+
−
+
−try:
+
−    import Crypto
+
−except ImportError:
+
−    _md4 = None
+
−    SHA256 = None
+
−else:
+
−    from Crypto.Hash import MD4 as _md4
+
−    if hasattr(Crypto, 'version_info'):  # <- Available since v2.1.0alpha1
+
−        from Crypto.Hash import SHA256   # SHA256 works since v2.1.0alpha1
+
−        sha256 = SHA256.new
+
−    else:
+
−        SHA256 = None
+
−    del Crypto
+
−
+
−
+
−compat = 0x01
+
−md5 = _md5.new
+
−sha1 = _sha1.new
+
−
+
−
+
−def new(name, string=''):
+
−    """Return a new hashing object using the named algorithm, optionally
+
−    initialized with the provided string.
+
−    """
+
−    if name in ('md5', 'MD5'):
+
−        return _md5.new(string)
+
−    if name in ('sha1', 'SHA1'):
+
−        return _sha1.new(string)
+
−    if not _md4:
+
−        raise ValueError('unsupported hash type')
+
−    if name in ('md4', 'MD4'):
+
−        return _md4.new(string)
+
−    if name in ('sha256', 'SHA256') and SHA256:
+
−        return SHA256.new(string)
+
−    raise ValueError('unsupported hash type')