mirror of
https://github.com/django/django.git
synced 2024-12-27 03:25:58 +00:00
127 lines
5.7 KiB
Plaintext
127 lines
5.7 KiB
Plaintext
=========================================
|
|
How to authenticate using ``REMOTE_USER``
|
|
=========================================
|
|
|
|
This document describes how to make use of external authentication sources
|
|
(where the web server sets the ``REMOTE_USER`` environment variable) in your
|
|
Django applications. This type of authentication solution is typically seen on
|
|
intranet sites, with single sign-on solutions such as IIS and Integrated
|
|
Windows Authentication or Apache and `mod_authnz_ldap`_, `CAS`_, `Cosign`_,
|
|
`WebAuth`_, `mod_auth_sspi`_, etc.
|
|
|
|
.. _mod_authnz_ldap: https://httpd.apache.org/docs/2.2/mod/mod_authnz_ldap.html
|
|
.. _CAS: https://www.apereo.org/projects/cas
|
|
.. _Cosign: http://weblogin.org
|
|
.. _WebAuth: https://uit.stanford.edu/service/authentication
|
|
.. _mod_auth_sspi: https://sourceforge.net/projects/mod-auth-sspi
|
|
|
|
When the web server takes care of authentication it typically sets the
|
|
``REMOTE_USER`` environment variable for use in the underlying application. In
|
|
Django, ``REMOTE_USER`` is made available in the :attr:`request.META
|
|
<django.http.HttpRequest.META>` attribute. Django can be configured to make
|
|
use of the ``REMOTE_USER`` value using the ``RemoteUserMiddleware``
|
|
or ``PersistentRemoteUserMiddleware``, and
|
|
:class:`~django.contrib.auth.backends.RemoteUserBackend` classes found in
|
|
:mod:`django.contrib.auth`.
|
|
|
|
Configuration
|
|
=============
|
|
|
|
First, you must add the
|
|
:class:`django.contrib.auth.middleware.RemoteUserMiddleware` to the
|
|
:setting:`MIDDLEWARE` setting **after** the
|
|
:class:`django.contrib.auth.middleware.AuthenticationMiddleware`::
|
|
|
|
MIDDLEWARE = [
|
|
"...",
|
|
"django.contrib.auth.middleware.AuthenticationMiddleware",
|
|
"django.contrib.auth.middleware.RemoteUserMiddleware",
|
|
"...",
|
|
]
|
|
|
|
Next, you must replace the :class:`~django.contrib.auth.backends.ModelBackend`
|
|
with :class:`~django.contrib.auth.backends.RemoteUserBackend` in the
|
|
:setting:`AUTHENTICATION_BACKENDS` setting::
|
|
|
|
AUTHENTICATION_BACKENDS = [
|
|
"django.contrib.auth.backends.RemoteUserBackend",
|
|
]
|
|
|
|
With this setup, ``RemoteUserMiddleware`` will detect the username in
|
|
``request.META['REMOTE_USER']`` and will authenticate and auto-login that user
|
|
using the :class:`~django.contrib.auth.backends.RemoteUserBackend`.
|
|
|
|
Be aware that this particular setup disables authentication with the default
|
|
``ModelBackend``. This means that if the ``REMOTE_USER`` value is not set
|
|
then the user is unable to log in, even using Django's admin interface.
|
|
Adding ``'django.contrib.auth.backends.ModelBackend'`` to the
|
|
``AUTHENTICATION_BACKENDS`` list will use ``ModelBackend`` as a fallback
|
|
if ``REMOTE_USER`` is absent, which will solve these issues.
|
|
|
|
Django's user management, such as the views in ``contrib.admin`` and
|
|
the :djadmin:`createsuperuser` management command, doesn't integrate with
|
|
remote users. These interfaces work with users stored in the database
|
|
regardless of ``AUTHENTICATION_BACKENDS``.
|
|
|
|
.. note::
|
|
|
|
Since the ``RemoteUserBackend`` inherits from ``ModelBackend``, you will
|
|
still have all of the same permissions checking that is implemented in
|
|
``ModelBackend``.
|
|
|
|
Users with :attr:`is_active=False
|
|
<django.contrib.auth.models.User.is_active>` won't be allowed to
|
|
authenticate. Use
|
|
:class:`~django.contrib.auth.backends.AllowAllUsersRemoteUserBackend` if
|
|
you want to allow them to.
|
|
|
|
If your authentication mechanism uses a custom HTTP header and not
|
|
``REMOTE_USER``, you can subclass ``RemoteUserMiddleware`` and set the
|
|
``header`` attribute to the desired ``request.META`` key. For example::
|
|
|
|
from django.contrib.auth.middleware import RemoteUserMiddleware
|
|
|
|
|
|
class CustomHeaderMiddleware(RemoteUserMiddleware):
|
|
header = "HTTP_AUTHUSER"
|
|
|
|
.. warning::
|
|
|
|
Be very careful if using a ``RemoteUserMiddleware`` subclass with a custom
|
|
HTTP header. You must be sure that your front-end web server always sets or
|
|
strips that header based on the appropriate authentication checks, never
|
|
permitting an end-user to submit a fake (or "spoofed") header value. Since
|
|
the HTTP headers ``X-Auth-User`` and ``X-Auth_User`` (for example) both
|
|
normalize to the ``HTTP_X_AUTH_USER`` key in ``request.META``, you must
|
|
also check that your web server doesn't allow a spoofed header using
|
|
underscores in place of dashes.
|
|
|
|
This warning doesn't apply to ``RemoteUserMiddleware`` in its default
|
|
configuration with ``header = 'REMOTE_USER'``, since a key that doesn't
|
|
start with ``HTTP_`` in ``request.META`` can only be set by your WSGI
|
|
server, not directly from an HTTP request header.
|
|
|
|
If you need more control, you can create your own authentication backend
|
|
that inherits from :class:`~django.contrib.auth.backends.RemoteUserBackend` and
|
|
override one or more of its attributes and methods.
|
|
|
|
.. _persistent-remote-user-middleware-howto:
|
|
|
|
Using ``REMOTE_USER`` on login pages only
|
|
=========================================
|
|
|
|
The ``RemoteUserMiddleware`` authentication middleware assumes that the HTTP
|
|
request header ``REMOTE_USER`` is present with all authenticated requests. That
|
|
might be expected and practical when Basic HTTP Auth with ``htpasswd`` or
|
|
similar mechanisms are used, but with Negotiate (GSSAPI/Kerberos) or other
|
|
resource intensive authentication methods, the authentication in the front-end
|
|
HTTP server is usually only set up for one or a few login URLs, and after
|
|
successful authentication, the application is supposed to maintain the
|
|
authenticated session itself.
|
|
|
|
:class:`~django.contrib.auth.middleware.PersistentRemoteUserMiddleware`
|
|
provides support for this use case. It will maintain the authenticated session
|
|
until explicit logout by the user. The class can be used as a drop-in
|
|
replacement of :class:`~django.contrib.auth.middleware.RemoteUserMiddleware`
|
|
in the documentation above.
|