ldapauthenticator

Simple LDAP Authenticator Plugin for JupyterHub

Installation

You can install it from pip with:

pip install jupyterhub-ldapauthenticator

Requirements

I've only tested with python3 - anyone willing to test with python2 is welcome to do so! There's no reason it shouldn't work.

Logging people out

If you make any changes to JupyterHub's authentication setup that changes which group of users is allowed to login (such as changing allowed_groups or even just turning on LDAPAuthenticator), you have to change the jupyterhub cookie secret, or users who were previously logged in and did not log out would continue to be able to log in!

You can do this by deleting the jupyterhub_cookie_secret file. Note that this will log out all users who are currently logged in.

Usage

You can enable this authenticator with the folling lines in your jupyter_config.py:

c.JupyterHub.authenticator_class = 'ldapauthenticator.LDAPAuthenticator'

Required configuration

At least the following two configuration options must be set before the LDAP Authenticator can be used:

LDAPAuthenticator.server_address

Address of the LDAP Server to contact. Just use a bare hostname or IP, without a port name or protocol prefix.

LDAPAuthenticator.bind_dn_template

Template to use to generate the full dn for a user from the human readable username.This must be set to either empty [] or to a list of templates users belong to. For example, if some of the users in your LDAP database have DN of the form uid=Yuvipanda,ou=people,dc=wikimedia,dc=org and some other users have DN like uid=Mike,ou=developers,dc=wikimedia,dc=org where Yuvipanda and Mike are the usernames, you would set this config item to be:

c.LDAPAuthenticator.bind_dn_template = [
    'uid={username},ou=people,dc=wikimedia,dc=org',
    'uid={username},ou=developers,dc=wikimedia,dc=org'

Don't forget the preceeding c. for setting configuration parameters! JupyterHub uses traitlets for configuration, and the c represents the config object.

The {username} is expanded into the username the user provides.

Optional configuration

LDAPAuthenticator.allowed_groups

LDAP groups whose members are allowed to log in. This must be set to either empty [] (the default, to disable) or to a list of full DNs that have a member attribute that includes the current user attempting to log in.

As an example, to restrict access only to people in groups researcher or operations,

c.LDAPAuthenticator.allowed_groups = [
    'cn=researcher,ou=groups,dc=wikimedia,dc=org',
    'cn=operations,ou=groups,dc=wikimedia,dc=org'
]

LDAPAuthenticator.valid_username_regex

All usernames will be checked against this before being sent to LDAP. This acts as both an easy way to filter out invalid usernames as well as protection against LDAP injection attacks.

By default it looks for the regex ^[a-z][.a-z0-9_-]*$ which is what most shell username validators do.

LDAPAuthenticator.use_ssl

Boolean to specify whether to use SSL encryption when contacting the LDAP server. Highly recommended that this be left to True (the default) unless there are very good reasons otherwise.

LDAPAuthenticator.server_port

Port to use to contact the LDAP server. Defaults to 389 if no SSL is being used, and 636 is SSL is being used.

LDAPAuthenticator.lookup_dn

Whether to try a reverse lookup to obtain the user's DN. Some LDAP servers, such as Active Directory, don't always bind with the true DN, so this allows us to discover it based on the username.

c.LDAPAuthenticator.lookup_dn = True

LDAPAuthenticator.user_search_base

Only used with lookup_dn=True. Defines the search base for looking up users in the directory.

c.LDAPAuthenticator.user_search_base = 'ou=People,dc=example,dc=com'

LDAPAuthenticator.user_attribute

Only used with lookup_dn=True. Defines the attribute that stores a user's username in your directory.

# Active Directory
c.LDAPAuthenticator.user_attribute = 'sAMAccountName'

# OpenLDAP
c.LDAPAuthenticator.user_attribute = 'uid'

Compatibility

This has been tested against an OpenLDAP server, with the client running Python 3.4. Verifications of this code working well with other LDAP setups welcome, as are bug reports and patches to make it work with other LDAP setups!