pas.plugins.oidc 1.0a6

An add-on for Plone

pas.plugins.oidc

This is an Plone authentication plugin for OpenID Connect. OAuth 2.0 should work as well, because OpenID Connect is built on top of this protocol.

Features

• PAS plugin, although currently no interfaces are activated.

• Three browser views for this PAS plugin, which are the main interaction with the outside world.

Installation

Install pas.plugins.oidc by adding it to your buildout:

[buildout]

...

eggs =
    pas.plugins.oidc

and then running bin/buildout

Warning

Pay attention to the customization of User info property used as userid field, with the wrong configuration it’s easy impersonate another user.

Example setup with Keycloak

Setup Keycloak as server

Please refer to the Keycloak documentation for up to date instructions. Specifically, here we will use a Docker image, so follow the instructions on how to get started with Keycloak on Docker. This does not give you a production setup, but it is fine for local development.

Keycloak runs on port 8080 by default. Plone uses the same port. When you are reading this, you probably know how to let Plone use a different port. So let’s indeed let Keycloak use its preferred port. At the moment of writing, this is how you start a Keycloak container:

docker run -p 8080:8080 -e KEYCLOAK_ADMIN=admin -e KEYCLOAK_ADMIN_PASSWORD=admin quay.io/keycloak/keycloak:19.0.3 start-dev

The plugin can be used with legacy(deprecated) keycloak redirect_uri parameter. To use this you need to enable the option in the plugin configuration. To test that you can run the keycloak server with the option–spi-login-protocol-openid-connect-legacy-logout-redirect-uri=true:

docker run -p 8080:8080 -e KEYCLOAK_ADMIN=admin -e KEYCLOAK_ADMIN_PASSWORD=admin quay.io/keycloak/keycloak:19.0.3 start-dev --spi-login-protocol-openid-connect-legacy-logout-redirect-uri=true

Note: when you exit this container, it still exists and you can restart it so you don’t lose your configuration. With docker ps -a figure out the name of the container and then use docker container start -ai <name>.

Follow the Keycloak Docker documentation further:

• Create a realm. Give this the name plone.

• Create a user. Remember to set a password for this user in the Credentials tab.

• Open a different browser and check that you can login to Keycloak with this user.

In the original browser, follow the steps for securing your first app. But we will be using different settings for Plone. And when last I checked, the actual UI differed from the documentation. So:

• Make sure you are logged in as admin in Keycloak, and are in the Plone realm.

• Go to Clients.

• Click ‘Create client’:

  • client type: OpenID Connect

  • client ID: plone

  • Turn ‘always display in console’ on. Useful for testing.

  • Click Next and Save.

• Now you can fill in the Access settings. We will assume Plone runs on port 8081:

  • Root URL: http://localhost:8081/Plone/

  • Home URL: http://localhost:8081/Plone/

  • Valid redirect URIs: http://localhost:8081/Plone*

  • Leave the rest at the defaults, unless you know what you are doing, and click Save.

Keycloak is ready.

Setup Plone as client

• In your Zope instance configuration, make sure Plone runs on port 8081.

• Make sure pas.plugins.oidc is installed with pip or Buildout.

• Start Plone and create a Plone site with id Plone.

• In the Add-ons control panel, install pas.plugins.oidc.

• In the ZMI go to the plugin properties at http://localhost:8081/Plone/acl_users/oidc/manage_propertiesForm

• Set these properties:

  • OIDC/Oauth2 Issuer: http://localhost:8080/realms/plone/

  • client ID: plone. This must match the client ID you have set in Keycloak.

  • Use deprecated redirect_uri. Use this if you need to run old versions of keycloak.

  • Leave the rest at the default and save the changes.

[TODO] screenshot.

Attention, before keycloak 18, the parameter for logout was redirect_uri and it is deprecated since version 18. But the keycloak server can run with the redirect_uri if needed, it is possible to use the plugin with the legacy parameter enabled also. The problem is that if the deprecated parameter is enabled in the plugin but not in the server, the plugin will not work.

So this is the way it works:

• With legacy enabled in keycloak, the plugin works in default mode.

• With legacy enabled in keycloak, the plugin also works with legacy mode.

• With legacy disabled in keycloak(default after version 18), the plugin works in default mode.

• With legacy disabled in keycloak(default after version 18), the plugin do NOT works with legacy mode.

So, for keycloak, it do not matter if we use the default or legacy mode if the keycloak runs in legacy mode.

If legacy is disabled in keycloak, this is the default since version 18 of keycloak according to this comment in starckoverflow: https://stackoverflow.com/a/72142887, the plugin will work only if the option use legacy mode is off(un-checked).

Login

Go to the other browser, or logout as admin from Keycloak. Currently, the Plone login form is unchanged. Instead, go to the login page of the plugin: http://localhost:8081/Plone/acl_users/oidc/login This will take you to Keycloak to login, and then return. You should now be logged in to Plone, and see the fullname and email, if you have set this in Keycloak.

Logout

If the login did worked as expected you can try to logout.

Go to the logout page of the plugin: http://localhost:8081/Plone/acl_users/oidc/logout This will take you to Keycloak to logout, and then return to the post logout redirect url.

Usage of sessions in the login process

This plugin uses sessions during the login process to identify the user while he goes to the OIDC provider and comes back from there.

The plugin has 2 ways of working with sessions:

• Use the Zope Session Management: if the “Use Zope session data manager” option in the plugin configuration is enabled, the plugin will use the sessioning configuration configured in Zope. To do so we advise to use Products.mcdutils to save the session data in a memcached based storage. Otherwise Zope will try to use ZODB based sessioning which has shown several problems in the past.

• Use the cookie based session management: if the “Use Zope session data manager” option in the plugin configuration is disabled, the plugin will use a Cookie to save that information in the client’s browser.

Settings in environment variables

Instead of editing your OIDC provider settings through the ZMI, you can use collective.regenv and provide a YAML file with your settings. This is very useful if you have different settings in different environments and and you do not want to edit the settings each time you move the contents.

Varnish

If you are using the Varnish caching server in front of Plone, you may see this plugin only partially working. Especially the came_from parameter may be ignored. This is because the standard configuration from plone.recipe.varnish removes most cookies to improve anonymous caching. Solution is to make sure the __ac_session cookie is added to the cookie-pass option. Check what the current default is in the recipe, and update it:

[varnish-configuration]
recipe = plone.recipe.varnish:configuration
...
cookie-pass = "auth_token|__ac(|_(name|password|persistent|session))=":"\.(js|css|kss)$"

Contribute

• Issue Tracker: https://github.com/collective/pas.plugins.oidc/issues

• Source Code: https://github.com/collective/pas.plugins.oidc

• Documentation: https://docs.plone.org/foo/bar

References

• Blog post: https://www.codesyntax.com/en/blog/log-in-in-plone-using-your-google-workspace-account

License

The project is licensed under the GPLv2.

Contributors

• mamico, [e-mail]

• erral, Mikel Larreategi

• alecghica, [e-mail]

• macagua, [e-mail]

Changelog

1.0a6 (2023-07-20)

• Added Spanish translation [macagua]

• Added improvements about i18n support [macagua]

• Drop python 2.7 and Plone 4 support [erral]

• Add support for the post_logout parameter for logout api. [ramiroluz]

1.0a5 (2023-04-05)

• Catch exceptions during the OAuth process [erral]

• Update the plugin to make challenges. An anonymous user who visits a page for which you have to be authenticated, is redirected to the new require_login view on the plugin. This works the same way as the standard require_login page of Plone. [maurits]

• Add a property for the default userinfo instead of using only sub. [eikichi18]

1.0a4 (2023-01-16)

• Call getProperty only once when getting redirect_uris or scope. [maurits]

• use getProperty accessor [mamico]

1.0a3 (2022-10-30)

• Removed the hardcoded auth cookie name [alecghica]

• Fixed Python compatibility with version >= 3.6 [alecghica]

• check if url is in portal before redirect #2 [erral]

• manage came_from [mamico]

1.0a2 (unreleased)

• do userinforequest if there is a client.userinfo_endpoint [mamico]

1.0a1 (unreleased)

• Initial release. [mamico]