Secure content distribution with distributed hardware

• US 8,837,722 B2
• Filed: 10/16/2007
• Issued: 09/16/2014
• Est. Priority Date: 10/16/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Schnell, Patrik, Alkove, James M., Grigorovitch, Alexandre V.
• Primary Examiner(s): Zand, Kambiz
• Assistant Examiner(s): Baum, Ronald
• Application Number:
  US11/872,832
• Publication Number:
  US 20090097642A1
• Time in Patent Office: 2,527 Days
• Field of Search: 380/200
• US Class Current: 380/200
• 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: H04N 21/4181 for conditional access
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/8355 involving usage data, e.g. number of copies or viewings allowed
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

This document describes tools capable of securely distributing entertainment content among and using distributed hardware. These tools may do so robustly by rebinding entertainment content between distributed hardware units. The tools, for example, may distribute content protection in hardware between a policy unit, a transcryption unit, a graphics processing unit, and a playback unit. By so doing the tools enable, among other things, users to select from many graphics cards rather than rely on the graphics capabilities of an integrated (e.g., SOC) hardware solution.

Claims

1. A device comprising:

a transcryption unit implemented, at least in part, in hardware, and configured to perform operations comprising;

establishing one or more first secure, authenticated communication channels with a hardware or software entity or entities capable of providing encrypted entertainment content and an encrypted signed policy associated with said encrypted entertainment content and governing usage rights of said encrypted entertainment content, said encrypted signed policy encrypted with a public key corresponding to a private key in the transcription unit;

receiving said encrypted entertainment content and said encrypted signed policy over said one or more first secure, authenticated communication channels;

decrypting said encrypted entertainment content to provide decrypted entertainment content;

decrypting said encrypted signed policy with the private key to provide a decrypted policy;

establishing a second secure, authenticated communication channel with a hardware graphics unit, hardware audio unit, or hardware device unit;

re-encrypting at least said decrypted entertainment content such that only said hardware graphics unit, hardware audio unit, or hardware device unit is permitted to decrypt at least said re-encrypted entertainment content;

receiving, over the second secure, authenticated communication channel, a request associated with the usage of the entertainment content from said hardware graphics unit, hardware audio unit, or hardware device unit;

sending, over the second secure, authenticated communication channel, said re-encrypted entertainment content to said hardware graphics unit, hardware audio unit, or hardware device unit;

determining whether the entertainment content has been utilized based, at least in part, on said received request associated with the usage of the entertainment content, wherein utilizing the entertainment content comprises at least one of;

copying the entertainment content;

or

playing the entertainment content;

and

responsive to determining the entertainment content has been utilized;

generating at least one indication of the utilization of said encrypted entertainment content; and

updating said decrypted policy to reflect the utilization of said encrypted entertainment content.

2. The device as described in claim 1, the transcription unit further configured to perform operations comprising:

receiving, over the one or more first secure, authenticated communication channels, an encrypted content key, said encrypted content key encrypted with a public key corresponding to a private key in the hardware transcryption unit, wherein the capability of decrypting said encrypted entertainment content comprises decrypting said encrypted content key with the private key to provide a decrypted content key and decrypting said encrypted entertainment content with the decrypted content key.

3. The device as described in claim 1, the transcription unit further configured to perform operations comprising:

receiving, over the one or more first secure, authenticated communication channels, a previously double-encrypted content key, said previously double-encrypted content key encrypted with a public key corresponding to a private key in the hardware transcryption unit and said previously double-encrypted content key having been doubly encrypted and decrypted to provide said previously double-encrypted content key by a policy unit prior to receipt by the hardware transcryption unit thereby prohibiting the policy unit from being able to decrypt the previously double-encrypted content key to provide a decrypted content key,

wherein the transcription unit is further configured to decrypt said encrypted entertainment content by decrypting said previously double-encrypted content key with the private key to provide a decrypted content key and decrypting said encrypted entertainment content with the decrypted content key.

4. The device as described in claim 3, wherein said previously double-encrypted content key is not received from said policy unit without said policy unit determining that a policy permits said hardware graphics unit, hardware audio unit, or hardware device unit to use said re-encrypted entertainment content.

5. The device as described in claim 1, wherein re-encrypting said decrypted entertainment content and said decrypted policy further comprises receiving a public key corresponding to a private key of said hardware graphics unit, hardware audio unit, or hardware device unit and re-encrypting said decrypted entertainment content and said decrypted policy with said public key.

6. The device as described in claim 1, the transcription unit further configured to perform operations comprising:

combining said decrypted entertainment content and said decrypted policy prior to re-encrypting said decrypted entertainment content to provide a combination of said decrypted entertainment content and said decrypted policy,

wherein re-encrypting said decrypted entertainment content further comprises re-encrypting the combination.

7. The device as described in claim 1, wherein the second secure, authenticated communication channel is established with said hardware graphics unit and wherein the transcryption unit is further configured to perform operations comprising:

establishing a third secure, authenticated communication channel with said hardware audio unit;

re-encrypting a second time said decrypted entertainment content such that only said hardware audio unit is capable of decrypting the second re-encrypted entertainment content; and

providing, over the third secure, authenticated communication channel, said second re-encrypted entertainment content to said hardware audio unit.

8. The device as described in claim 1, wherein the second secure, authenticated communication channel is established with said hardware device unit.

9. A method comprising:

establishing a secure, authenticated communication channel between distributed hardware units, the distributed hardware units comprising a transcryption unit and a graphics or audio unit effective to enable the transcryption unit to securely provide and the graphics or audio unit to securely receive entertainment content and associated policy with a hardware-based level of security, the graphics or audio unit further configured to;

decrypt the entertainment content and associated policy; and

mix the entertainment content with audio or video from other sources;

establishing a second secure, authenticated communication channel between said graphics or audio unit and an output device capable of rendering the entertainment content and mixed entertainment content;

receiving, over the second secure, authenticated communication channel, a request associated with the usage of the entertainment content from said graphics or audio unit;

determining, with the transcryption unit, whether the entertainment content has been utilized based, at least in part, on said received request associated with the usage of the entertainment content, wherein utilizing the entertainment content comprises at least one of;

copying the entertainment content;

or

playing the entertainment content;

and

responsive to determining the entertainment content has been utilized;

generating, using the transcryption unit, at least one indication of the utilization of said encrypted entertainment content; and

updating, using the transcryption unit, said associated policy to reflect the utilization of said encrypted entertainment content.

10. The method as described in claim 9, wherein the transcryption unit is part of a digital rights management (DRM) domain having one or more other transcryption units and further comprising establishing a second secure, authenticated communication channel between at least one of said one or more other transcryption units and said graphics or audio unit.

11. The method as described in claim 10, wherein the transcryption unit and said one or more other transcryption units have a same cryptographic key pair.

12. The method as described in claim 10, wherein the transcryption unit has a first cryptographic key pair and said one or more other transcryption units have a second cryptographic key pair, the first cryptographic key pair and the second cryptographic key pair being different.

13. The method as described in claim 12, further comprising receiving a content key at the transcryption unit that is encrypted with the first cryptographic key pair or at said one or more other transcryption units that is encrypted with the second cryptographic key pair, the first cryptographic key pair providing a hardware-based level of security and the second cryptographic key pair providing a software-based level of security.

14. The method as described in claim 9, wherein the act of establishing the secure, authenticated communication channel comprises establishing said channel using cryptographic certificates for each of the distributed hardware units.

15. The method as described in claim 9, further comprising establishing a third secure, authenticated communication channel between said graphics or audio unit and a second output device effective to enable the graphics or audio unit to securely provide the entertainment content to either or both of the first-mentioned output device and the second output device.

16. The method as described in claim 9, wherein said secure, authenticated communication channel is between said transcryption unit and said graphics unit and further comprising establishing a third secure, authenticated communication channel between said transcryption unit and a different, second graphics unit, the first-mentioned and second authenticated communication channels enabling secure receipt of the entertainment content by said first graphics unit and said second graphics unit, respectively.

17. One or more computer-readable storage memories comprising processor-executable instructions which, responsive to execution by at least one processor, are configured to enable a device to:

establish a secure, authenticated communication channel between distributed hardware units, the distributed hardware units comprising a transcryption unit and a graphics or audio unit effective to enable the transcryption unit to securely provide and the graphics or audio unit to securely receive entertainment content and associated policy with a hardware-based level of security, the graphics or audio unit further configured to;

decrypt the entertainment content and associated policy; and

mix the entertainment content with audio or video from other sources;

establish a second secure, authenticated communication channel between said graphics or audio unit and an output device capable of rendering the entertainment content and mixed entertainment content;

receiving, over the second secure, authenticated communication channel, a request associated with the usage of the entertainment content from said graphics or audio unit;

determine whether the entertainment content has been utilized based, at least in part, on the received request associated with the usage of the entertainment content, wherein utilizing the entertainment content comprises at least one of;

copying the entertainment content;

or

playing the entertainment content;

and

responsive to determining the entertainment content has been utilized;

generate at least one indication of the utilization of said encrypted entertainment content; and

update said associated policy to reflect the utilization of said encrypted entertainment content.

18. The one or more computer-readable storage memories of claim 17, wherein processor-executable instructions are further configured to enable the device to establish the secure, authenticated communication channel by establishing said channel using cryptographic certificates for each of the distributed hardware units.

19. The one or more computer-readable storage memories of claim 17, wherein the processor-executable instructions are further configured to enable the device to establish a third secure, authenticated communication channel between said graphics or audio unit and a second output device effective to enable the graphics or audio unit to securely provide the entertainment content to either or both of the first-mentioned output device and the second output device.