Patent ID: 7636826
Filing Date: 2009-12-22
Classification: G06F

Abstract:
1. An information storage device comprising: a memory for storing data; and a controller for performing access control on the memory, wherein the controller performs locking of the memory on the basis of a lock command and an identifier (ID) input from an information processing apparatus, and the controller determines, on the basis of the lock command, whether a key set including the identifier (ID) is (a) a standard lock key set serving as a key set prohibiting output, or (b) an export lock key set serving as a key set permitting output, and stores determination information in storage means, wherein the controller determines whether it is permitted to output the export lock key set to the information processing apparatus, and the determination includes verification of a key set unique to the information processing apparatus, which is input from the information processing apparatus, and the export lock key set is output to the information processing apparatus at least provided that the verification succeeds, and wherein the key set unique to the information processing apparatus is a primary key set [IDs, LKs] consisting of a primary ID (IDs) serving as a unique ID of the information processing apparatus and a primary lock key (LKs) serving as a lock key associated with the unique ID, the information storage device has a lock master key (LMK) that is applicable to compute the primary lock key (LKs), which is a hash value based on the relationship LKs=H(LMK, IDs), the hash value being computed for the primary ID (IDs) by applying the lock master key (LMK), and the controller verifies the key set unique to the information processing apparatus, which is input from the information processing apparatus, on the basis of a lock key (LK) obtained by computing the hash value by applying the lock master key (LMK).