Revocation method and apparatus for secure content

• US 7,672,903 B2
• Filed: 08/27/2001
• Issued: 03/02/2010
• Est. Priority Date: 08/27/2001
• Status: Active Grant

• Current Assignee: Chemtron Research LLC (Intellectual Ventures LLC)
• Original Assignee: DPHI Acquisitions, Inc.
• Inventors: Feldman, Timothy R., Lee, Lane W., Kiwimagi, Gary G., Rayburn, Douglas M.
• Primary Examiner(s): Fischer, Andrew J.
• Assistant Examiner(s): ZELASKIEWICZ, CHRYSTINA E
• Application Number:
  US09/939,896
• Publication Number:
  US 20030149668A1
• Time in Patent Office: 3,109 Days
• Field of Search: 705/51, 705 54- 57, 705/67, 705/75
• US Class Current: 705/51
• 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: G06Q 20/382 insuring higher security of transaction

Abstract

A system and method is provided for revoking a device. A method includes receiving a certificate from the device, the certificate including one or more of fields, at least one of the fields holding a signature, attempting to verify the signature, receiving a revocation list from a source, the revocation list identifying one or more data on the certificate as valid or invalid, the data including at least one of the fields of the certificate; and if one of one or more signatures identified unsuccessfully verified and one or more data is identified as invalid, preventing the transmission of a session key to the device, the session key being required to establish a secure communication channel.

Claims

1. A method of revoking a host device on a file-by-file basis, comprising:

receiving at a storage engine a certificate from the host device, the certificate containing a digital signature;

authenticating the digital signature;

establishing a secure session by transmitting a session key to the host device; and

during the secure session;

receiving at the storage engine a file request from the host device, the file request being directed to a file stored on a storage medium accessible to the storage engine;

reading a revocation list associated with the file from the storage medium, the revocation list containing at least one rule, the at least one rule associating data in the revocation list with data in the certificate;

applying the at least one rule on the data in the revocation list and the associated data in the certificate; and

if the application of the at least one rule provides a failing result, denying the file request.

2. The method of claim 1, wherein the at least one rule comprises a plurality of rules.

3. The method of claim 1, wherein the storage medium is an optical disk.

4. The method of claim 1, wherein the application of the at least one rule act comprises matching the data in the revocation file with the data in the certificate.

5. The method of claim 1, further comprising:

if the application of the at least one rule provides a successful result, granting the file request.