Storage medium processing method, storage medium processing device, and program

• US 8,126,150 B2
• Filed: 06/08/2005
• Issued: 02/28/2012
• Est. Priority Date: 06/16/2004
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kasahara, Akihiro, Miura, Akira, Suu, Hiroshi
• Primary Examiner(s): Orgad, Edan
• Assistant Examiner(s): HOLDER, BRADLEY W
• Application Number:
  US11/570,074
• Publication Number:
  US 20080260155A1
• Time in Patent Office: 2,456 Days
• Field of Search: 380/277, 380/278, 380/279
• US Class Current: 380/277
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 21/78 to assure secure storage of data address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/0084 wherein the usage restriction can be expressed as a specific time or date
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 2463/062 applying encryption of the keys cryptographic mechanisms or cryptographic arrangements for key distribution using key encryption key H04L9/0822
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 63/0853 using an additional device, e.g. smartcard, SIM or a different communication terminal cryptographic mechanisms or cryptographic arrangements for entity authentication involving additional secure or trusted devices H04L9/3234
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/083 involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying

Abstract

Spread of a forged storage medium is prevented suppressing an authentic storage medium'"'"'s damage and trouble of a owner to the minimum. When there is an update request of user key data, the update history of the user key data concerning the shown above-mentioned medium identifier IDm is referred to. When judged that the update of the user key data concerning the shown medium identifier IDm not being performed within a predetermined period, the update of user key data is performed. The request of a update is refused when judged that the update of the user key data concerning the shown medium identifier IDm being performed within a predetermined period.

Claims

1. A storage medium processing method for a storage medium and a user terminal, the storage medium being configured to store medium identifier data, medium unique key data generated based on the medium identifier data, user key data encrypted so that the user key data is decrypted using the medium unique key data, and content key data encrypted so that the content key data is decrypted using the user key data, the method comprising:

retaining, at the user terminal, content data encrypted so that the content data is decrypted using the content key data, the user terminal being connected to the storage medium;

requesting, at the user terminal to a license center, an update of both the user key data and an expiration term of the user key data from the license center by submitting the medium identifier data to the license center;

accessing, at the license center, an update history of the user key data corresponding to the submitted medium identifier data;

updating, at the license center, the user key data based on an update request, which includes an old user key, from the user terminal in response to an update of the user key data corresponding to the submitted medium identifier data having not been last performed within a predetermined period;

refusing, at the license center, the update request, which includes the old user key, from the user terminal in response to the update of the user key data corresponding to the submitted medium identifier data having last been performed within a predetermined period; and

displaying, at the user terminal, a message requesting a mailing of the storage medium after a refusal of the update request.

2. The storage medium processing method according to claim 1, wherein the updating of the user key data further includes generating new encrypted content key data by encrypting the content key data using an updated user key data.

3. The storage medium processing method according to claim 1, wherein

the user key data contains

data of a key body, and

management metadata for managing the user key data, and

the license center retains an original key body and only updates the management metadata.

4. A storage medium processing device comprising:

a storage medium connected to the storage medium processing device and configured to store medium identifier data, medium unique key data generated based on the medium identifier data, user key data encrypted so that the user key data is decrypted using the medium unique key data, and content key data encrypted so that the content key data is decrypted using the user key data;

a data processor for data-processing of the storage medium via a user terminal that stores content data encrypted so that the content data is decrypted using the content key data;

an update history database configured to retain an update history of user key data associated with the medium identifier data; and

a key delivery server configured

to receive an update request from the user terminal to update both the user key data and an expiration term of the user key data, the update request being accompanied by the medium identifier data,

to update the user key data and publish new user key data when the update request, which includes an old user key, is proper, the key delivery server referring to the update history database and determining that the update request is proper in response to an update of the user key data corresponding to the submitted medium identifier data having not been last performed within a predetermined period, the new user key data being transmitted to the user terminal, and

to refuse the update request, which includes the old user key, in response to the update of the user key data corresponding to the submitted medium identifier data having last been performed within a predetermined period,

wherein the key delivery server displays a message requesting a mailing of the storage medium after a refusal by the key deliver server to update the user key data.

5. The storage medium processing device according to claim 4, further comprising:

a user key database-configured to retain the user key data,

wherein the key delivery server rewrites the user key data stored in the user key database when performing the update of the user key data.

6. The storage medium processing device according to claim 4, wherein the key delivery server generates, when updating the user key data, new encrypted content key data by encrypting the content key data using the new user key data.

7. The storage medium processing device according to claim 4, wherein

the user key data contains

data of a key body, and

management metadata for managing the user key data, and

the key delivery server retains, when executing an update of the user key data, an original key body and updates only the management metadata.

8. A non-transitory computer-readable medium storing computer readable instructions thereon that when executed by a storage medium and a user terminal cause the user terminal to perform a method,

wherein the storage medium stores medium identifier data, medium unique key data generated based on the medium identifier data, user key data encrypted so that the user key data is decrypted using the medium unique key data, and content key data encrypted so that the content key data is decrypted using the user key data, the method comprising:

retaining, at a user terminal connected to the storage medium, content data encrypted so that the content data is decrypted using the content key data;

obtaining various kinds of data from a license center;

requesting both an update of the user key data and an expiration term of the user key data from the license center by submitting the medium identifier data to the license center;

retaining to an update history of the user key data corresponding to the submitted medium identifier data;

updating the user key data based on an update request, which includes an old user key, from the user terminal in response to an update of the user key data corresponding to the submitted medium identifier data having not been last performed within a predetermined period;

refusing the update request, which includes the old user key, from the user terminal in response to the update of the user key data corresponding to the submitted medium identifier data having last been performed within a predetermined period; and

displaying, at the user terminal, a message requesting a mailing of the storage medium after a refusal of the update request.

9. A server that manages an availability of content data in a user terminal, the server comprising:

a database configured to store an update history of user key data which is stored in a storage medium which is connected to the user terminal, the storage medium being configured to store medium identifier data, medium unique key data generated based on the medium identifier data, user key data encrypted so that the user key data is decrypted using the medium unique key data, and content key data encrypted so that the content key data is decrypted using the user key data, the user terminal being configured to obtain, via a network, encrypted content data corresponding to the content key data;

a receiving unit configured to receive from the user terminal an update request, which includes an old user key, to update both the user key data and an expiration term of the user key data, the update request being accompanied by medium identifier data;

a user key update unit configured to

refer to the update history of the user key data corresponding to the medium identifier data,

issue and transmit new user key data in response to the update history showing that an update of the user key data corresponding to submitted medium identifier data was not last performed within a predetermined period, and

transmit to the user terminal a response refusing to issue the new user key data and the updated expiration term in response to the update history showing that the update of the user key data corresponding to the submitted medium identifier data was last performed within a predetermined period,

wherein the user terminal displays a message requesting a mailing of the storage medium after a refusal of the update request.