crypto.py
author Christophe de Vienne <christophe@unlish.com>
Mon, 29 Dec 2014 12:35:34 +0100
changeset 10178 4b33246cb43c
parent 7879 9aae456abab5
child 10602 4845012cfc8e
permissions -rw-r--r--
[native] Change SQL errors log level. - The SQL error itself is logged as 'info'. - The 'transaction has been rolled back' message is logged as 'debug'. These log entries should not be critical: - If an error occur at the sql level, it will be transmitted as a CW error. The exception is raised and handled in a higher level function, which will decide if it is critical or not. - Admitting that rolling-back automatically on errors is wanted in some cases, it cannot be considered 'critical'. The caller will receive the original exception anyway, it is its job to decide if it is critical or not. Closes #4801120

# copyright 2003-2011 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
"""Simple cryptographic routines, based on python-crypto."""
__docformat__ = "restructuredtext en"

from pickle import dumps, loads
from base64 import b64encode, b64decode

from Crypto.Cipher import Blowfish


_CYPHERERS = {}
def _cypherer(seed):
    try:
        return _CYPHERERS[seed]
    except KeyError:
        _CYPHERERS[seed] = Blowfish.new(seed, Blowfish.MODE_ECB)
        return _CYPHERERS[seed]


def encrypt(data, seed):
    string = dumps(data)
    string = string + '*' * (8 - len(string) % 8)
    string = b64encode(_cypherer(seed).encrypt(string))
    return unicode(string)


def decrypt(string, seed):
    # pickle ignores trailing characters so we do not need to strip them off
    string = _cypherer(seed).decrypt(b64decode(string))
    return loads(string)