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z3c.bcrypt 2.0.0

Password manager utility using bcrypt or pbkdf2 encoding. Useful in combination with zope.password

z3c.bcrypt

z3c.bcrypt provides zope.password compatible “password manager” utilities that use bcrypt (or alternatively pbkdf2) encoding for storing passwords.

Both encoding schemes are implemented in the cryptacular library that is a dependency for this pacakge.

Using z3c.bcrypt

>>> from zope.interface.verify import verifyObject
>>> from zope.password.interfaces import IPasswordManager
>>> from z3c.bcrypt import BcryptPasswordManager
>>> manager = BcryptPasswordManager()
>>> verifyObject(IPasswordManager, manager)
True
>>> password = u"right \N{CYRILLIC CAPITAL LETTER A}"
>>> encoded = manager.encodePassword(password)
>>> encoded
'$2a$...'
>>> manager.checkPassword(encoded, password)
True
>>> manager.checkPassword(encoded, password + u"wrong")
False
>>> from z3c.bcrypt import PBKDF2PasswordManager
>>> manager = PBKDF2PasswordManager()
>>> verifyObject(IPasswordManager, manager)
True
>>> encoded = manager.encodePassword(password)
>>> encoded
u'$p5k2$...'
>>> manager.checkPassword(encoded, password)
True
>>> manager.checkPassword(encoded, password + u"wrong")
False
>>> # A previously encoded password, should be decodable even if the
>>> # current encoding of the same password is different::
>>> previouslyencoded = (
...     '$p5k2$1000$LgAFPIlc9CgrlSaxHyTUMA='
...     '=$IuUYplhMkR4qCl8-ONRVjEgJNwE=')
>>> encoded == previouslyencoded
False
>>> manager.checkPassword(previouslyencoded , password)
True

Excessively long “passwords” will take up a lot of computation time that can be used as a DOS attack vector. The password managers in z3c.bcrypt will only use the first 4096 characters of the incoming password for checking.

This is inspired by:

https://www.djangoproject.com/weblog/2013/sep/15/security/

This test would take significantly longer if the 4096 length limit would not be in place. XXX how to test that reliably?

>>> incomming = '$p5k2$1000$' + 'a' * 1024 * 1024 * 100  # lot of data.
>>> manager.checkPassword(encoded, incomming)
False

Configuration

This package provides a configure.zcml which installs implementations of the IPasswordManager as utilities:

>>> from zope.configuration import xmlconfig
>>> _ = xmlconfig.string("""
... <configure
...    xmlns="http://namespaces.zope.org/zope">
...
...    <include package="z3c.bcrypt" />
... </configure>
... """)
>>> from zope import component
>>> from zope.password.interfaces import IPasswordManager
>>> component.getUtility(IPasswordManager, name='bcrypt')
<z3c.bcrypt.passwordmanager.BcryptPasswordManager object at ...>
>>> component.getUtility(IPasswordManager, name='pbkdf2')
<z3c.bcrypt.passwordmanager.PBKDF2PasswordManager object at ...>

Changelog of z3c.bcrypt

2.0.0 (2017-05-10)

  • Standardize namespace __init__.
  • Add support for Python 3.4, 3.5, 3.6 and PyPy.

1.2 (2013-10-10)

1.1 (2010-02-22)

  • Fixes in the configure.zcml.

1.0 (2010-02-18)

  • Initial public release.
 
File Type Py Version Uploaded on Size
z3c.bcrypt-2.0.0-py2.py3-none-any.whl (md5) Python Wheel py2.py3 2017-05-10 9KB
z3c.bcrypt-2.0.0.tar.gz (md5) Source 2017-05-10 6KB