The virtio crypto device is a virtual cryptography device as well as a kind of
virtual hardware accelerator for virtual machines. The encryption and
decryption requests are placed in the data queue and are ultimately handled by the
backend crypto accelerators. The second queue is the control queue used to create
or destroy sessions for symmetric algorithms and will control some advanced
features in the future. The virtio crypto device provides the following crypto
services: CIPHER, MAC, HASH, AEAD etc.