Simple LDAP Authenticator Plugin for JupyterHub
You can install it from pip with:
pip install jupyterhub-ldapauthenticator
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.
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 must 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.
You can enable this authenticator with the following lines in your
jupyter_config.py
:
c.JupyterHub.authenticator_class = 'ldapauthenticator.LDAPAuthenticator'
At minimum, the following two configuration options must be set before the LDAP Authenticator can be used:
Address of the LDAP Server to contact. Just use a bare hostname or IP, without a port name or protocol prefix.
Template used 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 the
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.
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'
]
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.
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.
Port to use to contact the LDAP server. Defaults to 389 if no SSL is being used, and 636 is SSL is being used.
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
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'
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'
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 are welcome, as are bug reports and patches to make it work with other LDAP setups!
Currently, local user creation by the LDAPAuthenticator is unsupported as this is insecure since there's no cleanup method for these created users. As a result, users who are disabled in LDAP will have access to this for far longer.
Alternatively, there's good support in Linux for integrating LDAP into the system user setup directly, and users can just use PAM (which is supported in not just JupyterHub, but ssh and a lot of other tools) to log in. You can see http://www.tldp.org/HOWTO/archived/LDAP-Implementation-HOWTO/pamnss.html and lots of other documentation on the web on how to set up LDAP to provide user accounts for your system. Those methods are very widely used, much more secure and more widely documented. We recommend you use them rather than have JupyterHub create local accounts using the LDAPAuthenticator.
Issue #19 provides additional discussion on local user creation.