A storage device. In some embodiments, the storage device includes a storage interface, configured to be connected to a host computer, a processing circuit, and persistent storage media. The processing circuit may be configured to: read first data from the persistent storage media in response to a read command received through the storage interface; transmit second data through the storage interface, the second data being based on the first data; receive a write command, with third data, through the storage interface; write fourth data, based on the third data, to the persistent storage media; and perform a cryptographic operation on the first data or on the third data.