Source code for girder.models.password

#!/usr/bin/env python
# -*- coding: utf-8 -*-

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#  Copyright 2013 Kitware Inc.
#
#  Licensed under the Apache License, Version 2.0 ( the "License" );
#  you may not use this file except in compliance with the License.
#  You may obtain a copy of the License at
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#    http://www.apache.org/licenses/LICENSE-2.0
#
#  Unless required by applicable law or agreed to in writing, software
#  distributed under the License is distributed on an "AS IS" BASIS,
#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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import cherrypy
import hashlib
import re
import six

from girder import events
from girder.exceptions import ValidationException
from girder.utility import config
from .model_base import Model
from .token import genToken


[docs]class Password(Model): """ This model deals with managing user passwords. """
[docs] def initialize(self): self.name = 'password'
def _digest(self, alg, password, salt=None): """ Helper method to perform the password digest. :param alg: The hash algorithm to use. :type alg: str - 'sha512' | 'bcrypt' :param password: The password to digest. :type password: str :param salt: The salt to use. In the case of bcrypt, when storing the password, pass None; when testing the password, pass the hashed value. :type salt: None or str :returns: The hashed value as a string. """ cur_config = config.getConfig() if alg == 'sha512': return hashlib.sha512((password + salt).encode('utf8')).hexdigest() elif alg == 'bcrypt': try: import bcrypt except ImportError: raise Exception( 'Bcrypt module is not installed. See girder.local.cfg.') password = password.encode('utf8') if salt is None: rounds = int(cur_config['auth']['bcrypt_rounds']) return bcrypt.hashpw(password, bcrypt.gensalt(rounds)) else: if isinstance(salt, six.text_type): salt = salt.encode('utf8') return bcrypt.hashpw(password, salt) else: raise Exception('Unsupported hash algorithm: %s' % alg)
[docs] def validate(self, doc): if not doc.get('_id', ''): # Internal error, this should not happen raise Exception('Attempting to store empty password.') return doc
[docs] def hasPassword(self, user): """ Returns whether or not the given user has a password stored in the database. If not, it is expected that the user will be authenticated by an external service. :param user: The user to test. :type user: dict :returns: bool """ return 'hashAlg' in user
[docs] def authenticate(self, user, password): """ Authenticate a user. :param user: The user document. :type user: dict :param password: The attempted password. :type password: str :returns: Whether authentication succeeded (bool). """ if not self.hasPassword(user): e = events.trigger('no_password_login_attempt', { 'user': user, 'password': password }) if len(e.responses): return e.responses[-1] raise ValidationException( 'This user does not have a password. You must log in with an ' 'external service, or reset your password.') hash = self._digest(salt=user['salt'], alg=user['hashAlg'], password=password) if user['hashAlg'] == 'bcrypt': if isinstance(user['salt'], six.text_type): user['salt'] = user['salt'].encode('utf8') return hash == user['salt'] else: return self.load(hash, False) is not None
[docs] def encryptAndStore(self, password): """ Encrypt and store the given password. The exact internal details and mechanisms used for storage are abstracted away, but the guarantee is made that once this method is called on a password and the returned salt and algorithm are stored with the user document, calling Password.authenticate() with that user document and the same password will return True. :param password: The password to encrypt and store. :type password: str :returns: {tuple} (salt, hashAlg) The salt to store with the user document and the algorithm used for secure storage. Both should be stored in the corresponding user document as 'salt' and 'hashAlg' respectively. """ cur_config = config.getConfig() # Normally this would go in validate() but password is a special case. if not re.match(cur_config['users']['password_regex'], password): raise ValidationException( cur_config['users']['password_description'], 'password') alg = cherrypy.config['auth']['hash_alg'] if alg == 'bcrypt': """ With bcrypt, we actually need the one-to-one correspondence of hashed password to user, so we store the hash as the salt entry in the user table. """ salt = self._digest(alg=alg, password=password) else: """ With other hashing algorithms, we store the salt with the user and store the hashed value in a separate table with no correspondence to the user. """ salt = genToken() hash = self._digest(salt=salt, alg=alg, password=password) self.save({'_id': hash}) return salt, alg