Patent ID: 7721346
Filing Date: 2010-05-18
Classification: G06F,G11B

Abstract:
1. A storage device comprising: an ordinary data storage unit which stores encrypted contents data; a secret data storage unit which stores license data containing a contents key for decrypting the encrypted contents data; a cryptographic processing unit which receives, from a host device, and executes a command corresponding to each of a plurality of sequenced subprocesses produced by dividing each of a series of cryptographic input and output processes for encrypting data to be secured and inputting and outputting the data between the storage device and the host device; a controller which inputs and outputs the license data via the cryptographic processing unit and inputs and outputs the encrypted contents data bypassing the cryptographic processing unit; and a bus for receiving the command from the host device, the bus being deallocated for another command when the command is issued, wherein the cryptographic processing unit receives commands corresponding to a plurality of subprocesses respectively belonging to two or more different cryptographic input and output processes via the bus, refers to identifying information attached to the command, identifies to which cryptographic input and output process the command belongs, manages the sequence of commands executed in each cryptographic input and output process, and rejects the execution of an incorrectly sequenced command when the cryptographic processing unit receives the incorrectly sequenced command.