Configuring a Keystone identity provider

Configure the keystone identity provider to integrate your OpenShift Container Platform cluster with Keystone to enable shared authentication with an OpenStack Keystone v3 server configured to store users in an internal database. This configuration allows users to log in to OpenShift Container Platform with their Keystone credentials.

About identity providers in OpenShift Container Platform

By default, only a kubeadmin user exists on your cluster. To specify an identity provider, you must create a custom resource (CR) that describes that identity provider and add it to the cluster.

Note

OpenShift Container Platform user names containing /, :, and % are not supported.

About Keystone authentication

Keystone is an OpenStack project that provides identity, token, catalog, and policy services.

You can configure the integration with Keystone so that the new OpenShift Container Platform users are based on either the Keystone user names or unique Keystone IDs. With both methods, users log in by entering their Keystone user name and password. Basing the OpenShift Container Platform users on the Keystone ID is more secure because if you delete a Keystone user and create a new Keystone user with that user name, the new user might have access to the old user’s resources.

Creating the secret

Identity providers use OpenShift Container Platform Secret objects in the openshift-config namespace to contain the client secret, client certificates, and keys.

Procedure

Create a Secret object that contains the key and certificate by using the following command:

$ oc create secret tls <secret_name> --key=key.pem --cert=cert.pem -n openshift-config

Tip

You can alternatively apply the following YAML to create the secret:

apiVersion: v1
kind: Secret
metadata:
  name: <secret_name>
  namespace: openshift-config
type: kubernetes.io/tls
data:
  tls.crt: <base64_encoded_cert>
  tls.key: <base64_encoded_key>

Creating a config map

Identity providers use OpenShift Container Platform ConfigMap objects in the openshift-config namespace to contain the certificate authority bundle. These are primarily used to contain certificate bundles needed by the identity provider.

Procedure

Define an OpenShift Container Platform ConfigMap object containing the certificate authority by using the following command. The certificate authority must be stored in the ca.crt key of the ConfigMap object.
```
$ oc create configmap ca-config-map --from-file=ca.crt=/path/to/ca -n openshift-config
```
Tip

You can alternatively apply the following YAML to create the config map:
```
apiVersion: v1
kind: ConfigMap
metadata:
  name: ca-config-map
  namespace: openshift-config
data:
  ca.crt: |
    <CA_certificate_PEM>
```

Sample Keystone CR

The following custom resource (CR) shows the parameters and acceptable values for a Keystone identity provider.

Keystone CR

apiVersion: config.openshift.io/v1
kind: OAuth
metadata:
  name: cluster
spec:
  identityProviders:
  - name: keystoneidp 
    mappingMethod: claim 
    type: Keystone
    keystone:
      domainName: default 
      url: https://keystone.example.com:5000 
      ca: 
        name: ca-config-map
      tlsClientCert: 
        name: client-cert-secret
      tlsClientKey: 
        name: client-key-secret

This provider name is prefixed to provider user names to form an identity name.
Controls how mappings are established between this provider’s identities and User objects.
Keystone domain name. In Keystone, usernames are domain-specific. Only a single domain is supported.
The URL to use to connect to the Keystone server (required). This must use https.
Optional: Reference to an OpenShift Container Platform ConfigMap object containing the PEM-encoded certificate authority bundle to use in validating server certificates for the configured URL.
Optional: Reference to an OpenShift Container Platform Secret object containing the client certificate to present when making requests to the configured URL.
Reference to an OpenShift Container Platform Secret object containing the key for the client certificate. Required if tlsClientCert is specified.

Additional resources

See Identity provider parameters for information on parameters, such as mappingMethod, that are common to all identity providers.

Adding an identity provider to your cluster

After you install your cluster, add an identity provider to it so your users can authenticate.

Prerequisites

Create an OpenShift Container Platform cluster.
Create the custom resource (CR) for your identity providers.
You must be logged in as an administrator.

Procedure

Apply the defined CR:
```
$ oc apply -f </path/to/CR>
```
Note

If a CR does not exist, oc apply creates a new CR and might trigger the following warning: Warning: oc apply should be used on resources created by either oc create --save-config or oc apply. In this case you can safely ignore this warning.
Log in to the cluster as a user from your identity provider, entering the password when prompted.
```
$ oc login -u <username>
```
Confirm that the user logged in successfully, and display the user name.
```
$ oc whoami
```