Chapter 6. Encrypt at-rest swift objects

By default, objects uploaded to Object Storage are stored unencrypted. Because of this, it is possible to access objects directly from the file system. This can present a security risk if disks are not properly erased before they are discarded. When you have barbican enabled, the Object Storage service (swift) can transparently encrypt and decrypt your stored (at-rest) objects. At-rest encryption is distinct from in-transit encryption in that it refers to the objects being encrypted while being stored on disk.

Swift performs these encryption tasks transparently, with the objects being automatically encrypted when uploaded to swift, then automatically decrypted when served to a user. This encryption and decryption is done using the same (symmetric) key, which is stored in barbican.

Note

You cannot disable encryption after you have enabled encryption and added data to the swift cluster, because the data is now stored in an encrypted state. Consequently, the data will not be readable if encryption is disabled, until you re-enable encryption with the same key.

6.1. Enable at-rest encryption for swift

  1. You can enable the swift encryption capabilities by including SwiftEncryptionEnabled: True in your environment file, then re-running openstack overcloud deploy using /home/stack/overcloud_deploy.sh. Note that you still need to enable barbican, as described in the Install Barbican chapter.
  2. Confirm that swift is configured to use at-rest encryption:

    $ crudini --get /var/lib/config-data/puppet-generated/swift/etc/swift/proxy-server.conf pipeline-main pipeline
    
    pipeline = catch_errors healthcheck proxy-logging cache ratelimit bulk tempurl formpost authtoken keystone staticweb copy container_quotas account_quotas slo dlo versioned_writes kms_keymaster encryption proxy-logging proxy-server

    The result should include an entry for encryption.