Add support for OIDC (#389)

* added support for oidc auth

* fixed oidc usernames

* hiding password for users that aren't logged in via local auth

* add dependency, update settings

* keep change password link

* add tests

* add docs

---------

Co-authored-by: Sascha Ißbrücker <sascha.issbruecker@gmail.com>

README.md

@@ -43,9 +43,9 @@ The name comes from:
 - Installable as a Progressive Web App (PWA)
 - Extensions for [Firefox](https://addons.mozilla.org/firefox/addon/linkding-extension/) and [Chrome](https://chrome.google.com/webstore/detail/linkding-extension/beakmhbijpdhipnjhnclmhgjlddhidpe), as well as a bookmarklet
 - Light and dark themes
+- SSO support via OIDC or authentication proxies
 - REST API for developing 3rd party apps
 - Admin panel for user self-service and raw data access
-- Easy setup using Docker and a SQLite database, with PostgreSQL as an option
 
 
 **Demo:** https://demo.linkding.link/ ([see here](https://github.com/sissbruecker/linkding/issues/408) if you have trouble accessing it)

bookmarks/templates/registration/login.html

@@ -17,22 +17,24 @@
       {% endif %}
       <div class="form-group">
         <label class="form-label" for="{{ form.username.id_for_label }}">Username</label>
-        {{ form.username|add_class:'form-input'|attr:"placeholder: " }}
+        {{ form.username|add_class:'form-input'|attr:'placeholder: ' }}
       </div>
       <div class="form-group">
         <label class="form-label" for="{{ form.password.id_for_label }}">Password</label>
-        {{ form.password|add_class:'form-input'|attr:"placeholder: " }}
+        {{ form.password|add_class:'form-input'|attr:'placeholder: ' }}
       </div>
 
       <br/>
       <div class="d-flex justify-between">
-        <input type="submit" value="Login" class="btn btn-primary btn-wide">
+        <input type="submit" value="Login" class="btn btn-primary btn-wide"/>
-        <input type="hidden" name="next" value="{{ next }}">
+        <input type="hidden" name="next" value="{{ next }}"/>
+        {% if enable_oidc %}
+          <a class="btn btn-link" href="{% url 'oidc_authentication_init' %}">Login with OIDC</a>
+        {% endif %}
         {% if allow_registration %}
           <a href="{% url 'django_registration_register' %}" class="btn btn-link">Register</a>
         {% endif %}
       </div>
-
     </form>
   </section>
 {% endblock %}

bookmarks/templates/settings/general.html

@@ -150,7 +150,9 @@
             <i class="form-icon"></i> Import public bookmarks as shared
           </label>
           <div class="form-input-hint">
-            When importing bookmarks from a service that supports marking bookmarks as public or private (using the <code>PRIVATE</code> attribute), enabling this option will import all bookmarks that are marked as not private as shared bookmarks.
+            When importing bookmarks from a service that supports marking bookmarks as public or private (using the
+            <code>PRIVATE</code> attribute), enabling this option will import all bookmarks that are marked as not
+            private as shared bookmarks.
             Otherwise, all bookmarks will be imported as private bookmarks.
           </div>
         </div>

bookmarks/tests/test_login_view.py

@@ -0,0 +1,29 @@
+from django.test import TestCase, override_settings
+from django.urls import path, include
+
+from bookmarks.tests.helpers import HtmlTestMixin
+from siteroot.urls import urlpatterns as base_patterns
+
+# Register OIDC urls for this test, otherwise login template can not render when OIDC is enabled
+urlpatterns = base_patterns + [path("oidc/", include("mozilla_django_oidc.urls"))]
+
+
+@override_settings(ROOT_URLCONF=__name__)
+class LoginViewTestCase(TestCase, HtmlTestMixin):
+
+    def test_should_not_show_oidc_login_by_default(self):
+        response = self.client.get("/login/")
+        soup = self.make_soup(response.content.decode())
+
+        oidc_login_link = soup.find("a", text="Login with OIDC")
+
+        self.assertIsNone(oidc_login_link)
+
+    @override_settings(LD_ENABLE_OIDC=True)
+    def test_should_show_oidc_login_when_enabled(self):
+        response = self.client.get("/login/")
+        soup = self.make_soup(response.content.decode())
+
+        oidc_login_link = soup.find("a", text="Login with OIDC")
+
+        self.assertIsNotNone(oidc_login_link)

bookmarks/tests/test_oidc_support.py

@@ -0,0 +1,51 @@
+import importlib
+import os
+
+from django.test import TestCase, override_settings
+from django.urls import URLResolver
+
+
+class OidcSupportTest(TestCase):
+    def test_should_not_add_oidc_urls_by_default(self):
+        siteroot_urls = importlib.import_module("siteroot.urls")
+        importlib.reload(siteroot_urls)
+        oidc_url_found = any(
+            isinstance(urlpattern, URLResolver) and urlpattern.pattern._route == "oidc/"
+            for urlpattern in siteroot_urls.urlpatterns
+        )
+
+        self.assertFalse(oidc_url_found)
+
+    @override_settings(LD_ENABLE_OIDC=True)
+    def test_should_add_oidc_urls_when_enabled(self):
+        siteroot_urls = importlib.import_module("siteroot.urls")
+        importlib.reload(siteroot_urls)
+        oidc_url_found = any(
+            isinstance(urlpattern, URLResolver) and urlpattern.pattern._route == "oidc/"
+            for urlpattern in siteroot_urls.urlpatterns
+        )
+
+        self.assertTrue(oidc_url_found)
+
+    def test_should_not_add_oidc_authentication_backend_by_default(self):
+        base_settings = importlib.import_module("siteroot.settings.base")
+        importlib.reload(base_settings)
+
+        self.assertListEqual(
+            ["django.contrib.auth.backends.ModelBackend"],
+            base_settings.AUTHENTICATION_BACKENDS,
+        )
+
+    def test_should_add_oidc_authentication_backend_when_enabled(self):
+        os.environ["LD_ENABLE_OIDC"] = "True"
+        base_settings = importlib.import_module("siteroot.settings.base")
+        importlib.reload(base_settings)
+
+        self.assertListEqual(
+            [
+                "django.contrib.auth.backends.ModelBackend",
+                "mozilla_django_oidc.auth.OIDCAuthenticationBackend",
+            ],
+            base_settings.AUTHENTICATION_BACKENDS,
+        )
+        del os.environ["LD_ENABLE_OIDC"]  # Remove the temporary environment variable

bookmarks/utils.py

@@ -1,5 +1,6 @@
 import logging
 import re
+import unicodedata
 from datetime import datetime
 from typing import Optional
 
@@ -111,3 +112,12 @@ def get_safe_return_url(return_url: str, fallback_url: str):
     if not return_url or not re.match(r"^/[a-z]+", return_url):
         return fallback_url
     return return_url
+
+
+def generate_username(email):
+    # taken from mozilla-django-oidc docs :)
+
+    # Using Python 3 and Django 1.11+, usernames can contain alphanumeric
+    # (ascii and unicode), _, @, +, . and - characters. So we normalize
+    # it and slice at 150 characters.
+    return unicodedata.normalize("NFKC", email)[:150]

docs/Options.md

@@ -94,6 +94,31 @@ For example, for Authelia, which passes the `Remote-User` HTTP header, the `LD_A
 By default, the logout redirects to the login URL, which means the user will be automatically authenticated again.
 Instead, you might want to configure the logout URL of the auth proxy here.
 
+### `LD_ENABLE_OIDC`
+
+Values: `True`, `False` | Default = `False`
+
+Enables support for OpenID Connect (OIDC) authentication, allowing to use single sign-on (SSO) with OIDC providers.
+When enabled, this shows a button on the login page that allows users to authenticate using an OIDC provider.
+Users are associated by the email address provided from the OIDC provider, which is used as the username in linkding.
+If there is no user with that email address as username, a new user is created automatically. 
+
+This requires configuring a number of other options, which of those you need depends on which OIDC provider you use and how it is configured.
+In general, you should find the required information in the UI of your OIDC provider, or its documentation. 
+
+The options are adopted from the [mozilla-django-oidc](https://mozilla-django-oidc.readthedocs.io/en/stable/) library, which is used by linkding for OIDC support.
+Please check their documentation for more information on the options.
+
+The following options are available:
+- `OIDC_RP_CLIENT_ID` - Required. The client ID of your linkding instance in the OIDC provider.
+- `OIDC_OP_AUTHORIZATION_ENDPOINT` - Required. The authorization endpoint of the OIDC provider.
+- `OIDC_OP_TOKEN_ENDPOINT` - Required. The token endpoint of the OIDC provider.
+- `OIDC_OP_USER_ENDPOINT` - Required. The user info endpoint of the OIDC provider.
+- `OIDC_USE_PKCE` - Optional. Whether to use PKCE for the OIDC flow. Default is `True`. If you leave this enabled you should configure your OIDC provider to use the PKCE flow as well. You need to disable this if you want to use an authentication flow with a client secret.
+- `OIDC_RP_CLIENT_SECRET` - Optional. The client secret of the OIDC application. You need to disable PKCE if you want to use a client secret.
+- `OIDC_RP_SIGN_ALGO` - Optional. The signing algorithm to use for the OIDC flow. Default is `HS256`.
+- `OIDC_OP_JWKS_ENDPOINT` - Optional. The JWKS endpoint of the OIDC provider.
+
 ### `LD_CSRF_TRUSTED_ORIGINS`
 
 Values: `String` | Default = None

requirements.in

@@ -8,6 +8,7 @@ django-widget-tweaks
 django4-background-tasks
 djangorestframework
 Markdown
+mozilla-django-oidc
 psycopg2-binary
 python-dateutil
 requests

requirements.txt

@@ -14,17 +14,25 @@ bleach-allowlist==1.0.3
     # via -r requirements.in
 certifi==2023.11.17
     # via requests
+cffi==1.16.0
+    # via cryptography
 charset-normalizer==3.3.2
     # via requests
 click==8.1.7
     # via waybackpy
 confusable-homoglyphs==3.2.0
     # via django-registration
+cryptography==42.0.5
+    # via
+    #   josepy
+    #   mozilla-django-oidc
+    #   pyopenssl
 django==5.0.2
     # via
     #   -r requirements.in
     #   django-registration
     #   djangorestframework
+    #   mozilla-django-oidc
 django-registration==3.4
     # via -r requirements.in
 django-sass-processor==1.4
@@ -37,10 +45,18 @@ djangorestframework==3.14.0
     # via -r requirements.in
 idna==3.6
     # via requests
+josepy==1.14.0
+    # via mozilla-django-oidc
 markdown==3.5.2
     # via -r requirements.in
+mozilla-django-oidc==4.0.1
+    # via -r requirements.in
 psycopg2-binary==2.9.9
     # via -r requirements.in
+pycparser==2.21
+    # via cffi
+pyopenssl==24.1.0
+    # via josepy
 python-dateutil==2.8.2
     # via -r requirements.in
 pytz==2023.3.post1
@@ -48,6 +64,7 @@ pytz==2023.3.post1
 requests==2.31.0
     # via
     #   -r requirements.in
+    #   mozilla-django-oidc
     #   waybackpy
 six==1.16.0
     # via

scripts/setup-oicd.sh

@@ -0,0 +1,7 @@
+# Example setup for OIDC with Zitadel
+export LD_ENABLE_OIDC=True
+export OIDC_USE_PKCE=True
+export OIDC_OP_AUTHORIZATION_ENDPOINT=http://localhost:8080/oauth/v2/authorize
+export OIDC_OP_TOKEN_ENDPOINT=http://localhost:8080/oauth/v2/token
+export OIDC_OP_USER_ENDPOINT=http://localhost:8080/oidc/v1/userinfo
+export OIDC_RP_CLIENT_ID=258574559115018243@linkding

siteroot/settings/base.py

@@ -43,6 +43,7 @@ INSTALLED_APPS = [
     "rest_framework",
     "rest_framework.authtoken",
     "background_task",
+    "mozilla_django_oidc",
 ]
 
 MIDDLEWARE = [
@@ -182,6 +183,24 @@ MAX_ATTEMPTS = 5
 BACKGROUND_TASK_RUN_ASYNC = True
 BACKGROUND_TASK_ASYNC_THREADS = 2
 
+# Enable OICD support if configured
+LD_ENABLE_OIDC = os.getenv("LD_ENABLE_OIDC", False) in (True, "True", "1")
+
+AUTHENTICATION_BACKENDS = ["django.contrib.auth.backends.ModelBackend"]
+
+if LD_ENABLE_OIDC:
+    AUTHENTICATION_BACKENDS.append("mozilla_django_oidc.auth.OIDCAuthenticationBackend")
+
+    OIDC_USERNAME_ALGO = "bookmarks.utils.generate_username"
+    OIDC_RP_CLIENT_ID = os.getenv("OIDC_RP_CLIENT_ID")
+    OIDC_OP_AUTHORIZATION_ENDPOINT = os.getenv("OIDC_OP_AUTHORIZATION_ENDPOINT")
+    OIDC_OP_TOKEN_ENDPOINT = os.getenv("OIDC_OP_TOKEN_ENDPOINT")
+    OIDC_OP_USER_ENDPOINT = os.getenv("OIDC_OP_USER_ENDPOINT")
+    OIDC_USE_PKCE = os.getenv("OIDC_USE_PKCE", True) in (True, "True", "1")
+    OIDC_RP_CLIENT_SECRET = os.getenv("OIDC_RP_CLIENT_SECRET")
+    OIDC_RP_SIGN_ALGO = os.getenv("OIDC_RP_SIGN_ALGO", "HS256")
+    OIDC_OP_JWKS_ENDPOINT = os.getenv("OIDC_OP_JWKS_ENDPOINT")
+
 # Enable authentication proxy support if configured
 LD_ENABLE_AUTH_PROXY = os.getenv("LD_ENABLE_AUTH_PROXY", False) in (True, "True", "1")
 LD_AUTH_PROXY_USERNAME_HEADER = os.getenv(
@@ -194,9 +213,7 @@ if LD_ENABLE_AUTH_PROXY:
     # in the LD_AUTH_PROXY_USERNAME_HEADER request header
     MIDDLEWARE.append("bookmarks.middlewares.CustomRemoteUserMiddleware")
     # Configure auth backend that does not require a password credential
-    AUTHENTICATION_BACKENDS = [
+    AUTHENTICATION_BACKENDS = ["django.contrib.auth.backends.RemoteUserBackend"]
-        "django.contrib.auth.backends.RemoteUserBackend",
-    ]
     # Configure logout URL
     if LD_AUTH_PROXY_LOGOUT_URL:
         LOGOUT_REDIRECT_URL = LD_AUTH_PROXY_LOGOUT_URL

siteroot/urls.py

@@ -19,16 +19,27 @@ from django.contrib.auth import views as auth_views
 from django.urls import path, include
 
 from bookmarks.admin import linkding_admin_site
-from .settings import ALLOW_REGISTRATION, DEBUG
+
+
+class LinkdingLoginView(auth_views.LoginView):
+    """
+    Custom login view to lazily add additional context data
+    Allows to override settings in tests
+    """
+
+    def get_context_data(self, **kwargs):
+        context = super().get_context_data(**kwargs)
+
+        context["allow_registration"] = settings.ALLOW_REGISTRATION
+        context["enable_oidc"] = settings.LD_ENABLE_OIDC
+        return context
+
 
 urlpatterns = [
     path("admin/", linkding_admin_site.urls),
     path(
         "login/",
-        auth_views.LoginView.as_view(
+        LinkdingLoginView.as_view(redirect_authenticated_user=True),
-            redirect_authenticated_user=True,
-            extra_context=dict(allow_registration=ALLOW_REGISTRATION),
-        ),
         name="login",
     ),
     path("logout/", auth_views.LogoutView.as_view(), name="logout"),
@@ -45,13 +56,16 @@ urlpatterns = [
     path("", include("bookmarks.urls")),
 ]
 
+if settings.LD_ENABLE_OIDC:
+    urlpatterns.append(path("oidc/", include("mozilla_django_oidc.urls")))
+
 if settings.LD_CONTEXT_PATH:
     urlpatterns = [path(settings.LD_CONTEXT_PATH, include(urlpatterns))]
 
-if DEBUG:
+if settings.DEBUG:
     import debug_toolbar
 
     urlpatterns.append(path("__debug__/", include(debug_toolbar.urls)))
 
-if ALLOW_REGISTRATION:
+if settings.ALLOW_REGISTRATION:
     urlpatterns.append(path("", include("django_registration.backends.one_step.urls")))