protocol:
{
  "driver": "file",
  "filename": "/var/lib/libvirt/images/i.qcow2",
  "size": 4294967296
}

format:
{
  "driver": "qcow2",
  "file": "0123456789ABCDEF0123456789ABCDE",
  "size": 8589934590,
  "encrypt": {
    "key-secret": "0123456789ABCDEF0123456789ABCDE-encalias",
    "cipher-alg": "serpent-256",
    "cipher-mode": "cbc",
    "hash-alg": "sha256",
    "ivgen-alg": "plain64",
    "ivgen-hash-alg": "sha256",
    "format": "luks"
  }
}