Keycloak: Home IdP Discovery
This is a simple Keycloak authenticator to redirect users to their home identity provider during login.
What is it good for?
When a federated user wants to login via Keycloak, Keycloak will present a username/password form and a list of configured identity providers to the user. The user needs to choose an identity provider to get redirected. This authenticator allows to skip the step of selecting an identity provider.
How does it work?
If this authenticator gets configured as part of a browser based login flow, Keycloak will present a username form (without password form and without list of configured identity providers). A user can then enter an email address. Keycloak will then choose an identity provider based on the provided email domain and forward the user to the chosen provider.
How to install?
Download a release (*.jar file) that works with your Keycloak version from the list of releases.
Server
Copy the jar to the providers folder and execute the following command:
${kc.home.dir}/bin/kc.sh buildContainer image (Docker)
For Docker-based setups mount or copy the jar to /opt/keycloak/providers.
You may want to check docker-compose.yml as an example.
Maven/Gradle
Packages are being released to GitHub Packages. You find the coordinates here!
It may happen that I remove older packages without prior notice, because the storage is limited on the free tier.
How to configure?
Configure email domains
Email domains can be configured per identity provider. Currently, this can only be achieved via Identity Providers REST API. Make sure to post the full body, as you may receive from a GET request to the same endpoint, plus the home.idp.discovery.domains configuration.
PUT /{realm}/identity-provider/instances/{alias}
{
...
"config": {
"home.idp.discovery.domains": "example.com##example.net",
...
},
...
}
Note that domains need to be separated by two hashtags (##).
You can also use the Admin CLI (kcadm):
kcadm.sh update identity-provider/instances/{alias} -s 'config."home.idp.discovery.domains"="example.com##example.net"'Add Authenticator Execution
- Navigate to
Authentication - Create a custom
Browserflow - Click
Add execution - Select
Home IdP Discovery
Configuration options
To configure click: Actions > Config
| Option | Description |
|---|---|
| Forward to linked IdP | If switched on, federated users (with already linked IdPs) will be forwarded to a linked IdP even if no IdP has been configured for the user's email address. Federated users can also use their local username for login instead of their email address. If switched off, users will only be forwarded to IdPs with matching email domains. |
Show configured email domains in Admin console
- Navigate to
Realm Settings - Click
Themestab - Choose
home-idp-discoveryfor theAdmin Console Theme - Click
Save - Reload the admin console (press F5 in your browser)
- Navigate to an identity provider
- Click
Home IdP Discoverytab
Frequently asked questions
Does it (already) work with Quarkus/Keycloak.X?
Yes it does!
Please note that with the release of Keycloak 17.0.0 the Quarkus-based distro (aka Keycloak.X) is now fully supported by the Keycloak team. Hence, I dropped support for the Wildfly-based distro already. Though this library may still work with the Wildfly-based distro, I will no longer put any efforts into keeping this extension compatible.
Does it work with the legady Wildfly-based Keycloak distro?
Maybe! There is even a high chance it will, since this extension does not make use of any Quarkus-related functionality. For installation instructions, please refer to an older version of this readme.
Does it work with Keycloak version X.Y.Z?
If you are using Keycloak version X (e.g. X.y.z), version X.b.c should be compatible.
Keycloak SPIs are quite stable. So, there is a high chance this authenticator will work with other versions, too. Check the details of latest build results for an overview or simply give it a try.
Authenticator version X.b.c is compiled against Keycloak version X.y.z. For example, version 16.3.1 will be compiled against Keycloak version 16.y.z.
I do not guarantee what version a.b or y.z will be. Neither do I backport features to older version, nor maintain any older versions of this authenticator. If you need the latest features or bugfixes for an older version, please fork this project or update your Keycloak instance. I recommend doing the latter on regular basis anyways.