django-python3-ldap

Django LDAP user authentication backend for Python 3.


License
BSD-3-Clause
Install
pip install django-python3-ldap==0.9.12

Documentation

django-python3-ldap

django-python3-ldap provides a Django LDAP user authentication backend. Python 3.6+ is required.

Features

  • Authenticate users with an LDAP server.
  • Sync LDAP users with a local Django database.
  • Supports custom Django user models.

Installation

  1. Install using pip install django-python3-ldap.
  2. Add 'django_python3_ldap' to your INSTALLED_APPS setting.
  3. Set your AUTHENTICATION_BACKENDS setting to ("django_python3_ldap.auth.LDAPBackend",)
  4. Configure the settings for your LDAP server(s) (see Available settings, below).
  5. Optionally, run ./manage.py ldap_sync_users (or ./manage.py ldap_sync_users <list of user lookups>) to perform an initial sync of LDAP users.
  6. Optionally, run ./manage.py ldap_promote <username> to grant superuser admin access to a given user.

Available settings

Note: The settings below show their default values. You only need to add settings to your settings.py file that you intend to override.

# The URL of the LDAP server(s).  List multiple servers for high availability ServerPool connection.
LDAP_AUTH_URL = ["ldap://localhost:389"]

# Initiate TLS on connection.
LDAP_AUTH_USE_TLS = False

# Specify which TLS version to use (Python 3.10 requires TLSv1 or higher)
import ssl
LDAP_AUTH_TLS_VERSION = ssl.PROTOCOL_TLSv1_2

# The LDAP search base for looking up users.
LDAP_AUTH_SEARCH_BASE = "ou=people,dc=example,dc=com"

# The LDAP class that represents a user.
LDAP_AUTH_OBJECT_CLASS = "inetOrgPerson"

# User model fields mapped to the LDAP
# attributes that represent them.
LDAP_AUTH_USER_FIELDS = {
    "username": "uid",
    "first_name": "givenName",
    "last_name": "sn",
    "email": "mail",
}

# A tuple of django model fields used to uniquely identify a user.
LDAP_AUTH_USER_LOOKUP_FIELDS = ("username",)

# Path to a callable that takes a dict of {model_field_name: value},
# returning a dict of clean model data.
# Use this to customize how data loaded from LDAP is saved to the User model.
LDAP_AUTH_CLEAN_USER_DATA = "django_python3_ldap.utils.clean_user_data"

# Path to a callable that takes a user model, a dict of {ldap_field_name: [value]}
# a LDAP connection object (to allow further lookups), and saves any additional
# user relationships based on the LDAP data.
# Use this to customize how data loaded from LDAP is saved to User model relations.
# For customizing non-related User model fields, use LDAP_AUTH_CLEAN_USER_DATA.
LDAP_AUTH_SYNC_USER_RELATIONS = "django_python3_ldap.utils.sync_user_relations"

# Path to a callable that takes a dict of {ldap_field_name: value},
# returning a list of [ldap_search_filter]. The search filters will then be AND'd
# together when creating the final search filter.
LDAP_AUTH_FORMAT_SEARCH_FILTERS = "django_python3_ldap.utils.format_search_filters"

# Path to a callable that takes a dict of {model_field_name: value}, and returns
# a string of the username to bind to the LDAP server.
# Use this to support different types of LDAP server.
LDAP_AUTH_FORMAT_USERNAME = "django_python3_ldap.utils.format_username_openldap"

# Sets the login domain for Active Directory users.
LDAP_AUTH_ACTIVE_DIRECTORY_DOMAIN = None

# The LDAP username and password of a user for querying the LDAP database for user
# details. If None, then the authenticated user will be used for querying, and
# the `ldap_sync_users`, `ldap_clean_users` commands will perform an anonymous query.
LDAP_AUTH_CONNECTION_USERNAME = None
LDAP_AUTH_CONNECTION_PASSWORD = None

# Set connection/receive timeouts (in seconds) on the underlying `ldap3` library.
LDAP_AUTH_CONNECT_TIMEOUT = None
LDAP_AUTH_RECEIVE_TIMEOUT = None

Microsoft Active Directory support

django-python3-ldap is configured by default to support login via OpenLDAP. To connect to a Microsoft Active Directory, you need to modify your settings file.

For simple usernames (e.g. "username"):

LDAP_AUTH_FORMAT_USERNAME = "django_python3_ldap.utils.format_username_active_directory"

For down-level login name formats (e.g. "DOMAIN\username"):

LDAP_AUTH_FORMAT_USERNAME = "django_python3_ldap.utils.format_username_active_directory"
LDAP_AUTH_ACTIVE_DIRECTORY_DOMAIN = "DOMAIN"

For user-principal-name formats (e.g. "user@domain.com"):

LDAP_AUTH_FORMAT_USERNAME = "django_python3_ldap.utils.format_username_active_directory_principal"
LDAP_AUTH_ACTIVE_DIRECTORY_DOMAIN = "domain.com"

Depending on how your Active Directory server is configured, the following additional settings may match your server better than the defaults used by django-python3-ldap:

LDAP_AUTH_USER_FIELDS = {
    "username": "sAMAccountName",
    "first_name": "givenName",
    "last_name": "sn",
    "email": "mail",
}

LDAP_AUTH_OBJECT_CLASS = "user"

Sync User Relations

As part of the user authentication process, django-python3-ldap calls a function specified by the LDAP_AUTH_SYNC_USER_RELATIONS configuraton item. This function can be used for making additional updates to the user database (for example updaing the groups the user is a member of), or getting further information from the LDAP server.

The signature of the called function is:-

def sync_user_relations(user, ldap_attributes, *, connection=None, dn=None):

The parameters are:-

  • user - a Django user model object
  • ldap_attributes - a dict of LDAP attributes
  • connection - the LDAP connection object (optional keyword only parameter)
  • dn - the DN (Distinguished Name) of the LDAP matched user (optional keyword only parameter)

Clean User

When a LDAP user is removed from server it could be interresting to deactive or delete its local Django account to prevent unauthorized access.

To do so run:

./manage.py ldap_clean_users (or ./manage.py ldap_clean_users --purge).

It will deactivate all local users non declared on LDAP server. If --purge is specified, all local users will be deleted.

Can't get authentication to work?

LDAP is a very complicated protocol. Enable logging (see below), and see what error messages the LDAP connection is throwing.

Logging

Print information about failed logins to your console by adding the following to your settings.py file.

LOGGING = {
    "version": 1,
    "disable_existing_loggers": False,
    "handlers": {
        "console": {
            "class": "logging.StreamHandler",
        },
    },
    "loggers": {
        "django_python3_ldap": {
            "handlers": ["console"],
            "level": "INFO",
        },
    },
}

Custom user filters

By default, any users within LDAP_AUTH_SEARCH_BASE and of the correct LDAP_AUTH_OBJECT_CLASS will be considered a valid user. You can apply further filtering by setting a custom LDAP_AUTH_FORMAT_SEARCH_FILTERS callable.

# settings.py
LDAP_AUTH_FORMAT_SEARCH_FILTERS = "path.to.your.custom_format_search_filters"

# path/to/your/module.py
from django_python3_ldap.utils import format_search_filters

def custom_format_search_filters(ldap_fields):
    # Add in simple filters.
    ldap_fields["memberOf"] = "foo"
    # Call the base format callable.
    search_filters = format_search_filters(ldap_fields)
    # Advanced: apply custom LDAP filter logic.
    search_filters.append("(|(memberOf=groupA)(memberOf=GroupB))")
    # All done!
    return search_filters

The returned list of search filters will be AND'd together to make the final search filter.

How it works

When a user attempts to authenticate, a connection is made to one of the listed LDAP servers, and the application attempts to bind using the provided username and password.

If the bind attempt is successful, the user details are loaded from the LDAP server and saved in a local Django User model. The local model is only created once, and the details will be kept updated with the LDAP record details on every login.

To perform a full sync of all LDAP users to the local database, run ./manage.py ldap_sync_users. This is not required, as the authentication backend will create users on demand. Syncing users has the advantage of allowing you to assign permissions and groups to the existing users using the Django admin interface.

Running ldap_sync_users as a background cron task is another optional way to keep all users in sync on a regular basis.

Support and announcements

Downloads and bug tracking can be found at the main project website.

More information

The django-python3-ldap project was developed by Dave Hall. You can get the code from the django-python3-ldap project site.

Dave Hall is a freelance web developer, based in Cambridge, UK. You can usually find him on the Internet in a number of different places: