Issuing a Publisher Use License Off-Line in a Digital Rights Management (DRM) System

• US 20080215896A1
• Filed: 03/21/2008
• Published: 09/04/2008
• Est. Priority Date: 02/25/2003
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Bourne, Steve, Malaviarachchi, Rushmi U., Venkatesh, Chandramouli, Dillaway, Blair Brewster, Jacomet, Pierre, Parambir, Kumar B., Rozenfeld, Yevgeniy (Eugene), Rose, Charles F.
• Granted Patent: US 8,700,535 B2
• Time in Patent Office: Days
• US Class Current: 713/193
• CPC Class Codes: G06F 21/107 License processing; Key processing
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management data processing systems or methods, specially adapted for commerce, e.g. marketing, shopping, billing, auctions or e-commerce G06Q30/00
• CPC Class Codes: H04L 63/104 Grouping of entities

Abstract

A publishing user publishes digital content and issues to itself a corresponding digital publisher license to allow itself to render the published digital content. The publishing user is supplied with a publishing certificate from a digital rights management (DRM) server, where the publishing certificate allows the publishing user to so publish the digital content and to so issue the publisher license.

Claims

1. A method for a publishing user to render published digital content based on a self-issued corresponding digital publisher license, the content being encrypted by a content key (CK) to form (CK(content)) and the publisher license including (CK) encrypted by a public key (PU-ENTITY) associated with the publishing user to form (PU-ENTITY(CK)) and having attached thereto a publishing certificate from a digital rights management (DRM) server, the publishing certificate having a public key (PU-OLP) and a corresponding private key (PR-OLP) encrypted by (PU-ENTITY) to form (PU-ENTITY(PR-OLP)), the publisher license being signed by (PR-OLP), the method comprising:

verifying the publishing certificate based on the chain of certificates;

obtaining (PU-OLP) from the publishing certificate;

employing the obtained (PU-OLP) to verify the signature of the publisher license;

retrieving (PU-ENTITY(CK)) from the verified publisher license;

applying to (PU-ENTITY(CK)) a private key (PR-ENTITY) corresponding to (PU-ENTITY) to obtain (CK);

applying (CK) to (CK(content)) to result in the content; and

forwarding the content to a rendering application for actual rendering.

2. The method of claim 1 wherein the publishing certificate further has a digital signature and is accompanied by a chain of certificates leading back to a root authority, the method further comprising verifying the publishing certificate based on the signature thereof and the chain of certificates leading back to the root authority.

3. The method of claim 1 wherein the publisher license includes (PU-ENTITY(CK)) and rights data specifying rights and conditions that must be satisfied to allow rendering of the content, the method further comprising verifying that the specified rights and conditions of the rights data allow the rendering.

4. The method of claim 3 comprising creating the license data corresponding to the content package with (PU-ENTITY(CK)) and with the rights data in an encrypted form, the method further comprising decrypting the rights data.

5. A computer-readable medium having computer-executable instructions thereon for performing a method for a publishing user to render published digital content based on a self-issued corresponding digital publisher license, the content being encrypted by a content key (CK) to form (CK(content)) and the publisher license including (CK) encrypted by a public key (PU-ENTITY) associated with the publishing user to form (PU-ENTITY(CK)) and having attached thereto a publishing certificate from a digital rights management (DRM) server, the publishing certificate having a public key (PU-OLP) and a corresponding private key (PR-OLP) encrypted by (PU-ENTITY) to form (PU-ENTITY(PR-OLP)), the publisher license being signed by (PR-OLP), the method comprising:

verifying the publishing certificate based on the chain of certificates;

obtaining (PU-OLP) from the publishing certificate;

employing the obtained (PU-OLP) to verify the signature of the publisher license;

retrieving (PU-ENTITY(CK)) from the verified publisher license;

applying to (PU-ENTITY(CK)) a private key (PR-ENTITY) corresponding to (PU-ENTITY) to obtain (CK);

applying (CK) to (CK(content)) to result in the content; and

forwarding the content to a rendering application for actual rendering.

6. The medium of claim 5 wherein the publishing certificate further has a digital signature and is accompanied by a chain of certificates leading back to a root authority, the method further comprising verifying the publishing certificate based on the signature thereof and the chain of certificates leading back to the root authority.

7. The medium of claim 5 wherein the publisher license includes (PU-ENTITY(CK)) and rights data specifying rights and conditions that must be satisfied to allow rendering of the content, the method further comprising verifying that the specified rights and conditions of the rights data allow the rendering.

8. The medium of claim 7 wherein the method comprises creating the license data corresponding to the content package with (PU-ENTITY(CK)) and with the rights data in an encrypted form, the method further comprising decrypting the rights data.

9. A system for a publishing user to render published digital content based on a self-issued corresponding digital publisher license, the content being encrypted by a content key (CK) to form (CK(content)) and the publisher license including (CK) encrypted by a public key (PU-ENTITY) associated with the publishing user to form (PU-ENTITY(CK)) and having attached thereto a publishing certificate from a digital rights management (DRM) server, the publishing certificate having a public key (PU-OLP) and a corresponding private key (PR-OLP) encrypted by (PU-ENTITY) to form (PU-ENTITY(PR-OLP)), the publisher license being signed by (PR-OLP), comprising at least one subsystem that:

verifies the publishing certificate based on the chain of certificates;

obtains (PU-OLP) from the publishing certificate;

employs the obtained (PU-OLP) to verify the signature of the publisher license;

retrieves (PU-ENTITY(CK)) from the verified publisher license;

applies to (PU-ENTITY(CK)) a private key (PR-ENTITY) corresponding to (PU-ENTITY) to obtain (CK);

applies (CK) to (CK(content)) to result in the content; and

forwards the content to a rendering application for actual rendering.

10. The system of claim 9 wherein the publishing certificate further has a digital signature and is accompanied by a chain of certificates leading back to a root authority, further comprising at least one subsystem that verifies the publishing certificate based on the signature thereof and the chain of certificates leading back to the root authority.

11. The system of claim 9 wherein the publisher license includes (PU-ENTITY(CK)) and rights data specifying rights and conditions that must be satisfied to allow rendering of the content, further comprising at least one subsystem that verifies that the specified rights and conditions of the rights data allow the rendering.

12. The system of claim 11 further comprising at least one subsystem that creates the license data corresponding to the content package with (PU-ENTITY(CK)) and with the rights data in an encrypted form, at least one subsystem that decrypts the rights data.