Access to a storage device, such as a disk, is controlled by performing a disk operation using a single cryptographic engine. Keys associated with each layer of a layered structure associated with controlling access to the storage device are combined. The resultant of this combination is used as the key to the cryptographic engine. Data to be retrieved from and written to the storage device are operated on by the cryptographic engine utilizing the combined key. Keys are combined by combining functions associated with layers of the layered structure. A combining function can include an exclusive or function, a cryptographic hash function, or a combination thereof.