Volume Security
Available as of v1.4.0
Harvester v1.4.0 and later versions allow you to encrypt and decrypt virtual machine images. The encryption mechanism utilizes the Linux kernel module dm_crypt and the command-line utility cryptsetup.
Prerequisites
Prepare the following resources:
Secret: A Kubernetes secret is used as the passphrase of dm_crypt. You must specify the value of the
CRYPTO_KEY_VALUE
field. All other fields are fixed.Example Secret:
apiVersion: v1
kind: Secret
metadata:
name: encryption
namespace: default
data:
CRYPTO_KEY_CIPHER: aes-xts-plain64
CRYPTO_KEY_HASH: sha256
CRYPTO_KEY_PROVIDER: secret
CRYPTO_KEY_SIZE: 256
CRYPTO_KEY_VALUE: "Your encryption passphrase"
CRYPTO_PBKDF: argon2iimportantThe example contains the default YAML code for Kubernetes secrets. Aside from this, you can use encryption options for LUKS mode, which is a cryptsetup operating mode. Harvester v1.4.1 and later versions support these options, but you must verify that these are supported by your nodes.
Option Possible Values CRYPTO_KEY_CIPHER aes-xts-plain, aes-xts-plain64, aes-cbc-plain, aes-cbc-plain64, aes-cbc-essiv:sha256 CRYPTO_KEY_HASH sha256, sha384, sha512 CRYPTO_KEY_SIZE 256, 384, 512 CRYPTO_PBKDF argon2i, argon2id, pbkdf2 You can create a secret in the system namespace using kubectl or the Harvester UI (Edit as YAML feature). Resources in the system namespace are not displayed on the Harvester UI Secrets screen.
StorageClass: Images are encrypted using Longhorn, so required fields must be passed to the Longhorn CSI Driver. You can specify the encryption secret when creating a StorageClass. For more information, see Image StorageClass.
Example of a StorageClass:
allowVolumeExpansion: true
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: encryption
parameters:
csi.storage.k8s.io/node-publish-secret-name: encryption
csi.storage.k8s.io/node-publish-secret-namespace: default
csi.storage.k8s.io/node-stage-secret-name: encryption
csi.storage.k8s.io/node-stage-secret-namespace: default
csi.storage.k8s.io/provisioner-secret-name: encryption
csi.storage.k8s.io/provisioner-secret-namespace: default
encrypted: "true"
migratable: "true"
numberOfReplicas: "3"
staleReplicaTimeout: "2880"
provisioner: driver.longhorn.io
reclaimPolicy: Delete
volumeBindingMode: ImmediateimportantYou can create a secret in the system namespace using the Harvester UI (Edit as YAML feature) and kubectl. Resources in the system namespace are not displayed on the Harvester UI Secrets screen.
Encrypted Volumes
You can create an encrypted volume using an encrypted StorageClass on the following UI locations:
Volumes: Create screen
Volumes tab on the Virtual Machine: Create screen
Advanced Usage with Rancher Integration
The secret is an unencrypted Base64-encoded string. To keep the secret safe, you can use projects and namespaces to isolate permissions. For more information, see Multi-Tenancy.
Limitations
You cannot perform the following actions:
- Export a new volume from an encrypted volume
- Restore an encrypted volume to an unencrypted volume
- Restore an unencrypted volume to an encrypted volume