cubicweb/crypto.py
author Sylvain Thénault <sylvain.thenault@logilab.fr>
Tue, 08 Nov 2016 18:37:47 +0100
branch3.24
changeset 11808 4a387179fa33
parent 11767 432f87a63057
child 12567 26744ad37953
child 12615 7abe23cbfda1
permissions -rw-r--r--
[migration] Drop cw_schema relation first without this, we ends up with the traceback shown at https://www.cubicweb.org/ticket/16130960. This is not the proper fix, which I have not been able to find. It seems due to this very rare case of deletion of such relation linked to CWRType vs order of execution of operation (in this case, the operation deleting the entity table is run before some other queries using it). As forcing this relation to be deleted before the entity type fixes the problem while this case seems rare enough, IMO this patch is "good enough". Closes #16130960

# 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."""


from base64 import b64encode, b64decode

from six.moves import cPickle as pickle

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 = pickle.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 pickle.loads(string)