[rql rewriting] handle case where we've and optional inlined relation in the original query. Also, we should append EXISTS even in subquery to avoid inserting duplicates in results
"""Simple cryptographic routines, based on python-crypto.
:organization: Logilab
:copyright: 2009-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
"""
__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)