Digital rights management of a digital device

• US 8,572,408 B2
• Filed: 10/11/2004
• Issued: 10/29/2013
• Est. Priority Date: 11/05/2002
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Candelore, Brant L.
• Primary Examiner(s): Orgad, Edan
• Assistant Examiner(s): SCHMIDT, KARI L
• Application Number:
  US10/962,830
• Publication Number:
  US 20050063541A1
• Time in Patent Office: 3,305 Days
• Field of Search: 380/239, 380/281, 380/200, 380/201, 380/210, 713/155, 713/193, 713/165, 713/170, 713/189
• US Class Current: 713/193
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/2541 Rights Management protecting software against unauthorised usage in a vending or licensing environment G06F21/10; 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 21/43853 involving multiplex stream decryption arrangements using cryptography for the use of broadcast information or broadcast-related information H04H60/23
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/4623 Processing of entitlement messages, e.g. ECM [Entitlement Control Message] or EMM [Entitlement Management Message] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• 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 21/47211 for requesting pay-per-view content payment schemes payment architectures or payment protocols G06Q20/00, G07F
• CPC Class Codes: H04N 21/835 Generation of protective data, e.g. certificates protecting software against unauthorised usage in a vending or licensing environment G06F21/10
• CPC Class Codes: H04N 21/8355 involving usage data, e.g. number of copies or viewings allowed
• CPC Class Codes: H04N 7/165 Centralised control of user terminal subsequent to an upstream request signal H04N7/17345; Registering at central by two-way working H04N7/17309
• 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

According to one embodiment, an apparatus involves the descrambling of scrambled digital content using a one-time programmable key and digital rights management. The apparatus comprises a processor and a descrambler. The processor is adapted to execute a Digital Rights Management (DRM) function in order to determine whether each entitlement needed to access the digital content is pre-stored. The descrambler is adapted to decrypt encrypted information using a Unique Key stored within the one-time programmable memory. After determining that each entitlement needed to access the digital content is pre-stored, the decrypted information is used to generate a key, which is used to decrypt at least one service key for descrambling the scrambled digital content.

Claims

1. A method for descrambling scrambled digital content within a subscriber terminal device, comprising:

conducting digital rights management by a first component of the subscriber terminal device to determine whether entitlements needed for accessing digital content in a descrambled format are available to the subscriber terminal device; and

deriving a key within a second component of the subscriber terminal device logically separate from and independent of the first component in response to determining that all of the entitlements needed for accessing the digital content are available to the subscriber terminal device, the key being used to decrypt service keys used for descrambling the scrambled digital content, wherein deriving the key comprises decrypting encrypted data using a Unique Key and subsequently conducting hash operations on the decrypted data to produce the key, wherein the key is a hash value.

2. The method of claim 1, wherein the first component is the main central processing unit (CPU), and the second component is a descrambler.

3. The method of claim 1, wherein prior to deriving the key, the method further comprising:

prompting a subscriber of the subscriber terminal device to purchase an entitlement if the entitlement is needed to access the digital content and is currently unavailable to the subscriber terminal device.

4. The method of claim 3, wherein the prompting of the subscriber includes generating an image displayed on a display unit in communication with the subscriber terminal device, the image includes a selectable field.

5. The method of claim 4, wherein prior to deriving the key, the method further comprising:

sending a message to a headend upon selection of the selectable field, the message being a request for a selected entitlement to be sent to the subscriber terminal device.

6. The method of claim 5, wherein selection of the selectable field is performed by a control unit accessible to the subscriber.

7. The method of claim 1, wherein conducting digital rights management includes analyzing a plurality of entitlements to be enforced, each of the plurality of entitlements controlling playback of the digital content.

8. An apparatus adapted to receive and descramble scrambled digital content, comprising:

a processor to execute a Digital Rights Management (DRM) function to determine whether each entitlement needed to access the digital content in a descrambled format is pre-stored; and

a descrambler to decrypt encrypted information using a Unique Key stored within a one-time programmable memory of the descrambler, the decrypted information being used to generate a key that is used to decrypt at least one service key used to descramble the scrambled digital content and recover the digital content upon determining that each entitlement needed to access the digital content is pre-stored, wherein the descrambler comprises a sequence of process blocks forming a key ladder, the sequence of process blocks includes at least a first process block and a second process block, the first process block to decrypt a plurality of keys encrypted with the Unique Key to produce a plurality of decrypted keys and the second process block to conduct one-way hash operations using the plurality of decrypted keys to produce the key, wherein the key is a hash value.

9. The apparatus of claim 8, wherein the processor and the descrambler are placed on a single integrated circuit.

10. The apparatus of claim 8, wherein the the key ladder is arranged to produce the key to recover the at least one service key for descrambling of the scrambled digital content.

11. The apparatus of claim 10, wherein the descrambler is implemented with the sequence of process blocks each having a dedicated function without a processor being employed within the descrambler.

12. The apparatus of claim 11, wherein a first process block of the sequence of process blocks to decrypt a plurality of keys encrypted with the Unique Key to produce a plurality of decrypted keys.

13. The apparatus of claim 12, wherein a second process block of the sequence of process blocks to conduct one-way hash operations using at least one of the plurality of decrypted keys and at least one pre-computed hash value to produce the key.

14. The apparatus of claim 13, wherein a third process block of the sequence of process blocks to descramble the incoming scrambled digital content to produce descrambled digital content.

15. The apparatus of claim 10 being coupled to a display, a hard disk recording unit and a subscriber terminal device over a transmission medium, wherein the descrambler comprises encrypting logic coupled to the plurality of process blocks, the encrypting logic to receive the descrambled digital content and to re-encrypt the digital content for transmission to the subscriber terminal device over the transmission medium.

16. An integrated circuit device adapted to descramble incoming scrambled content, comprising:

a first component to execute a Digital Rights Management (DRM) function; and

a second component including a one-time programmable memory storing a Unique Key and operating fully independent from the DRM function,

the second component being implemented with a sequence of process blocks forming a key ladder, the sequence of process blocks including at least a first process block and a second process block,

the second component, when operable, to decrypt encrypted information using the Unique Key in the first process block to produce decrypted information, and the decrypted information being hashed in the second process block to generate a key that is used to decrypt at least one service key used to descramble the scrambled content upon determining that each entitlement needed to access the content is stored within the integrated circuit, wherein the key is a hash value.

17. The integrated circuit device of claim 16, wherein the first component and the second component are placed on a single integrated circuit.

18. The integrated circuit device of claim 16, wherein the first component is a processor.

19. The integrated circuit device of claim 18, wherein the second component is a descrambler implemented with the sequence of process blocks each having a dedicated function, the key ladder arranged to produce the key to recover the at least one service key.