Secrets Store Container Storage Interface Driver Operator¶

To improve secret security and integrate with enterprise secret management systems, you can use the Secrets Store CSI Driver Operator to mount secrets from external stores without persisting them on the cluster after pod termination.

Overview of Secrets Store CSI Driver Operator¶

To store and manage your secrets securely, configure the Secrets Store CSI Driver Operator to mount secrets from an external secret management system, such as Azure Key Vault, by using a provider plugin. Applications can then use the secret, but the secret does not persist on the system after pod termination.

Secret objects are stored with Base64 encoding. etcd provides encryption at rest for these secrets, but when secrets are retrieved, they are decrypted and presented to the user. If role-based access control is not configured properly on your cluster, anyone with API or etcd access can retrieve or modify a secret. Additionally, anyone who is authorized to create a pod in a namespace can use that access to read any secret in that namespace.

The Secrets Store CSI Driver Operator, secrets-store.csi.k8s.io, enables OpenShift Container Platform to mount multiple secrets, keys, and certificates stored in enterprise-grade external secrets stores into pods as a volume. The Secrets Store CSI Driver Operator communicates with the provider using gRPC to fetch the mount contents from the specified external secrets store. After the volume is attached, the data in it is mounted into the container’s file system. Secrets store volumes are mounted in-line.

For more information about CSI inline volumes, see "CSI inline ephemeral volumes".

Familiarity with persistent storage and configuring CSI volumes is recommended when working with a CSI driver. For more information, see "Understanding persistent storage" and "Configuring CSI volumes".

Secrets store providers¶

You can store sensitive information needed by your applications in an external secret management system and use the Secrets Store CSI Driver Operator to mount the secret content as a pod volume. Using an external secret store protects information that you do not want developers to have and can be more secure than secret objects.

The Secrets Store CSI Driver Operator has been tested with the following secrets store providers:

• AWS Secrets Manager
• AWS Systems Manager Parameter Store
• Azure Key Vault
• Google Secret Manager
• HashiCorp Vault

About CSI¶

The Container Storage Interface (CSI) enables storage vendors to deliver plugins through a standard interface without modifying Kubernetes core code, replacing traditional embedded storage drivers.

CSI Operators give OpenShift Container Platform users storage options, such as volume snapshots, that are not possible with in-tree volume plugins.

Support for disconnected environments¶

You can use certain secrets store providers in disconnected OpenShift Container Platform clusters by configuring VPC endpoints or equivalent connectivity to enable communication between the driver and external secret management systems.

The following secrets store providers support using the Secrets Store CSI driver in disconnected clusters:

• AWS Secrets Manager
• Azure Key Vault
• Google Secret Manager
• HashiCorp Vault

To enable communication between Secrets Store CSI driver and the secrets store provider, configure Virtual Private Cloud (VPC) endpoints or equivalent connectivity to the corresponding secrets store provider, the OpenID Connect (OIDC) issuer, and the Secure Token Service (STS). The exact configuration depends on the secrets store provider, the authentication method, and the type of disconnected cluster.

Support for network policies¶

The Secrets Store CSI Driver Operator uses pre-defined NetworkPolicies to control ingress and egress traffic for enhanced security of the Operator and driver components.

The following table summarizes the default ingress and egress rules:

Installing the Secrets Store CSI driver¶

To enable OpenShift Container Platform to mount secrets from external secret management systems, install the Secrets Store CSI Driver Operator and create a ClusterCSIDriver instance.

Prerequisites

• Access to the OpenShift Container Platform web console.
• Administrator access to the cluster.

Procedure

1. Install the Secrets Store CSI Driver Operator:
   1. Log in to the web console.
   2. Click Ecosystem → Software Catalog.
   3. Locate the Secrets Store CSI Driver Operator by typing "Secrets Store CSI" in the filter box.
   4. Click the Secrets Store CSI Driver Operator button.
   5. On the Secrets Store CSI Driver Operator page, click Install.
   6. On the Install Operator page, ensure that:
      • All namespaces on the cluster (default) is selected.
      • Installed Namespace is set to openshift-cluster-csi-drivers.
   7. Click Install.

      After the installation finishes, the Secrets Store CSI Driver Operator is listed in the Installed Operators section of the web console.

2. Create the ClusterCSIDriver instance for the driver (secrets-store.csi.k8s.io):
   1. Click Administration → CustomResourceDefinitions → ClusterCSIDriver.
   2. On the Instances tab, click Create ClusterCSIDriver.

      Use the following YAML file:

      yaml

      apiVersion: operator.openshift.io/v1
      kind: ClusterCSIDriver
      metadata:
          name: secrets-store.csi.k8s.io
      spec:
        managementState: Managed

   3. Click Create.

Installing the Secrets Store CSI driver by using the CLI¶

The Secrets Store CSI driver is typically installed in the namespace openshift-cluster-csi-drivers. This namespace is present in the cluster as part of the installation of the Cluster Storage Operator.

Procedure

1. Create an OperatorGroup object by running the following command:
   terminal

   $ oc apply -f - <<EOF
   apiVersion: operators.coreos.com/v1
   kind: OperatorGroup
   metadata:
     name: openshift-cluster-csi-drivers
     namespace: openshift-cluster-csi-drivers
   spec: {}
   EOF

2. Create a Subscription object by running the following command:
   terminal

   $ oc apply -f - <<EOF
   apiVersion: operators.coreos.com/v1alpha1
   kind: Subscription
   metadata:
     name: secrets-store-csi-driver-operator
     namespace: openshift-cluster-csi-drivers
   spec:
     channel: stable
     installPlanApproval: Automatic
     name: secrets-store-csi-driver-operator
     source: redhat-operators
     sourceNamespace: openshift-marketplace
   EOF

3. Wait for the Operator to be up and running. You can check the Operator status by running the following command:
   terminal

   $ oc get csv -n openshift-cluster-csi-drivers

   Example output

   NAME    DISPLAY     VERSION         RELEASE   REPLACES   PHASE
   secrets-store-csi-driver-operator.v4.22.0-202607151755   Secrets Store CSI Driver Operator   4.22.0-202607151755                        Succeeded

4. Create the Cluster CSI driver by running the following command:
   terminal

   $ oc apply -f - <<EOF
   apiVersion: operator.openshift.io/v1
   kind: ClusterCSIDriver
   metadata:
     name: secrets-store.csi.k8s.io
   spec:
     managementState: Managed
   EOF

Verification

• Verify that the Operator is running:
  terminal

  $ oc get operator -n openshift-cluster-csi-drivers

  Example output

  NAME                                                             AGE
  secrets-store-csi-driver-operator.openshift-cluster-csi-drivers   7m55s

• Verify that the pods are running:
  terminal

  $ oc get pods -n openshift-cluster-csi-drivers

  Example output

  NAME                                                 READY   STATUS    RESTARTS   AGE
  ....
  ....
  secrets-store-csi-driver-node-bhp2d                  3/3     Running   0          45s
  secrets-store-csi-driver-operator-74696fc7bc-qjrl8   1/1     Running   0          7m40s

Uninstalling the Secrets Store CSI Driver Operator¶

To remove the Secrets Store CSI Driver Operator and free cluster resources, uninstall the Operator after stopping applications and removing the CSI driver.

Prerequisites

• Access to the OpenShift Container Platform web console.
• Administrator access to the cluster.

Procedure

1. Stop all application pods that use the secrets-store.csi.k8s.io provider.
2. Remove any third-party provider plug-in for your chosen secret store.
3. Remove the Container Storage Interface (CSI) driver and associated manifests:
   1. Click Administration → CustomResourceDefinitions → ClusterCSIDriver.
   2. On the Instances tab, for secrets-store.csi.k8s.io, on the far left side, click the drop-down menu, and then click Delete ClusterCSIDriver.
   3. When prompted, click Delete.
4. Verify that the CSI driver pods are no longer running.
5. Uninstall the Secrets Store CSI Driver Operator:
   Note

   Before you can uninstall the Operator, you must remove the CSI driver first.

   1. Click Ecosystem → Installed Operators.
   2. On the Installed Operators page, scroll or type "Secrets Store CSI" into the Search by name box to find the Operator, and then click it.
   3. On the upper, right of the Installed Operators > Operator details page, click Actions → Uninstall Operator.
   4. When prompted on the Uninstall Operator window, click the Uninstall button to remove the Operator from the namespace. Any applications deployed by the Operator on the cluster need to be cleaned up manually.

      After uninstalling, the Secrets Store CSI Driver Operator is no longer listed in the Installed Operators section of the web console.