Encryption At Rest

encryptionAtRest variable enables encrypting kubernetes resources at rest using provided encryption provider. When this variable is set, kuberntetes secrets and configmaps are encrypted before writing them at etcd.

If the encryptionAtRest property is not specified, then the customization will be skipped. The secrets and configmaps will not be stored as encrypted in etcd.

We support following encryption providers

• aescbc
• secretbox

More information about encryption at-rest: Encrypting Confidential Data at Rest

Example

To encrypt configmaps and secrets kubernetes resources using aescbc encryption provider:

apiVersion: cluster.x-k8s.io/v1beta1
kind: Cluster
metadata:
  name: <NAME>
spec:
  topology:
    variables:
      - name: clusterConfig
        value:
          encryptionAtRest:
            providers:
              - aescbc: {}

Applying this configuration will result in

1. <CLUSTER_NAME>-encryption-config secret generated.

A secret key for the encryption provider is generated and stored in <CLUSTER_NAME>-encryption-config secret. The APIServer will be configured to use the secret key to encrypt secrets and configmaps kubernetes resources before writing them to etcd. When reading resources from etcd, encryption provider that matches the stored data attempts in order to decrypt the data. CAREN currently does not rotate the key once it generated.

1. Configure APIServer with encryption configuration:

• KubeadmControlPlaneTemplate:

    spec:
      kubeadmConfigSpec:
        clusterConfiguration:
          apiServer:
            extraArgs:
              encryption-provider-config: /etc/kubernetes/pki/encryptionconfig.yaml
      files:
        - contentFrom:
            secret:
              key: config
              name: <CLUSTER_NAME>-encryption-config
          path: /etc/kubernetes/pki/encryptionconfig.yaml
          permissions: "0640"