Media content protection utilizing public key cryptography

• US 6,438,235 B2
• Filed: 08/05/1998
• Issued: 08/20/2002
• Est. Priority Date: 08/05/1998
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Sims, J. Robert III
• Primary Examiner(s): Decady, Albert
• Assistant Examiner(s): KABAKOFF, STEPHEN ERIC
• Application Number:
  US09/129,370
• Publication Number:
  US 20020016919A1
• Time in Patent Office: 1,476 Days
• Field of Search: 380/282, 380/279, 380/283, 380/285, 705/51, 705/52, 705/54, 705/56
• US Class Current: 380/285
• 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 21/445 by mutual authentication, e.g. between devices or programs
• CPC Class Codes: G06F 2211/008 Public Key, Asymmetric Key, Asymmetric Encryption
• CPC Class Codes: G06F 2221/2121 Chip on media, e.g. a disk or tape with a chip embedded in its case
• CPC Class Codes: G06F 2221/2129 Authenticate client device independently of the user
• CPC Class Codes: G06F 2221/2135 Metering
• CPC Class Codes: G06Q 20/10 specially adapted for electronic funds transfer [EFT] systems; specially adapted for home banking systems
• CPC Class Codes: G06Q 20/367 involving electronic purses or money safes
• 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 20/00137 involving measures which result in a restriction to contents recorded on or reproduced from a record carrier to authorised users
• CPC Class Codes: G11B 20/00144 involving a user identifier, e.g. a unique customer ID
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00253 wherein the key is stored on the record carrier
• CPC Class Codes: G11B 20/00543 wherein external data is encrypted, e.g. for secure communication with an external device or for encrypting content on a separate record carrier
• CPC Class Codes: G11B 20/0071 involving a purchase action
• CPC Class Codes: G11B 20/00746 wherein the usage restriction can be expressed as a specific number
• CPC Class Codes: G11B 20/00768 wherein copy control information is used, e.g. for indicating whether a content may be copied freely, no more, once, or never, by setting CGMS, SCMS, or CCI flags

Abstract

A system and method for providing protection of content stored on a bulk storage media is disclosed. The technique for providing protection from unauthorized utilization of the content so stored is provided publicly in order to allow for those utilizing a conforming media device to master or generate content protected according to the present invention. Various ways in which to protect content are disclosed including verification of the authenticity of a particular media, utilization of an accepted list of media play-back devices and their corresponding published public keys in order to securely pass media content keys thereto, and utilization of an external contact to provide media content keys and/or updates of accepted media play-back devices.

Claims

1. A method for preventing unauthorized access to content stored on a media, comprising:

receiving a request to access content stored on a media from a particular play-back device including an identifier indicative of a type of device of said particular play-back device;

matching said identifier to a list of authorized play-back device types, said list being stored on said media; and

when said identifier matches one entry of said list of authorized play-back device types, performing the steps of;

(i) retrieving a public key associated with said one entry from said media;

(ii) retrieving a content key utilized to encrypt said content from said media;

(iii) encrypting said content key with said public key, and

(iv) communicating said encrypted content key to said particular play-back device.

2. The method of claim 1 further comprising:

controlling a drive unit reading said media to prevent said particular play-back device from directly accessing portions of said media which contain the content key.

3. The method of claim 2 wherein said content key is interspersed at different portions of said media.

4. The method of claim 1 wherein said content key is encoded as errors on said media via an error correction code.

5. The method of claim 1 wherein said content key is stored on an active portion of said media.

6. The method of claim 5 wherein said active portion includes a processor which is operable to only communicate said content key in encrypted form.

7. The method of claim 1 wherein said content key is a private key.

8. The method of claim 1 further comprising the steps of:

receiving an encrypted random number from said particular play-back device; and

decrypting said encrypted random number;

wherein said step of encrypting said content key with said public key, includes the sub-step of performing an exclusive-or (XOR) operation with said content key and said random number.

9. The method of claim 1 wherein said media is a mass distributed media.

10. A system for preventing unauthorized utilization of content, comprising:

a processor operating under a set of instructions to control access to content stored on a media utilizing access information stored on said media and validation information received from a particular play-back device;

said content being encrypted with a media cryptographic key, said media cryptographic key being stored on said media;

said access information including a list of identifiers of a plurality of authorized play-back device types;

said access information further including a respective device cryptographic key for each authorized play-back device type of said plurality of authorized play-back device types;

said set of instructions including code to receive said validation information from said particular play-back device in a request to read said content on said media;

said set of instructions including code to determine whether said received validation information matches one of said identifiers of said list of identifiers; and

said set of instructions including code to communicate said media cryptographic key encrypted by said respective device cryptographic key associated with said particular play-back device type to said particular play-back device when said validation information matches one of said identifiers.

11. The system of claim 10 wherein said processor controls a drive unit for recovering information from said media.

12. The system of claim 11 wherein said processor controls said drive unit by preventing said play-back device from directly accessing portions of said media which store said media cryptographic key.

13. The system of claim 11 within said media cryptographic key is stored at interspersed locations on said media, and wherein said set of instructions includes code for identifying said predetermined interspersed locations.

14. The system of claim 13 wherein said media cryptographic key is encoded as errors in data via an error correction code.

15. The system of claim 10 wherein said processor is implemented on an active portion of said media.

16. The system of claim 15 wherein said media cryptographic key is stored on said active portion.

17. The system of claim 16 wherein said processor prevents said particular play-back device from directly accessing said active portion to obtain said media cryptographic key.

18. The system of claim 10 wherein said media cryptographic key is a private key.

19. The system of claim 10 wherein each respective device cryptographic key is a public key.

20. The system of claim 10 wherein said set of instructions further includes code to receive an encrypted random number, code for decrypting said encrypted random number utilizing a respective device cryptographic key, and wherein said code to communicate is operable to perform an exclusive-or (XOR) operation on said media cryptographic key with said random number.

21. The system of claim 10 wherein said media is a mass distributed media.

22. A method for preventing unauthorized access to content, comprising:

storing content on a media encrypted with a content key, wherein said content key is stored on said media, and wherein said media is distributed in mass;

storing information indicative of authorized media player types on said media;

storing a respective public key for each authorized media player type of said authorized media player types on said media;

receiving from a particular media player a request to access said content from said media, wherein said request includes an identifier specifying a type of said particular media player;

validating said particular media player by matching said identifier against said information indicative of authorized media player types; and

when said validating step determines said particular media player is authorized, sending said content key encrypted by said respective public key associated with said particular media player to said particular media player.

23. The method of claim 22 further comprising:

controlling a drive unit to access data stored on said media.

24. The method of claim 23 wherein said step of controlling a drive unit prevents said particular media player from directly accessing portions of said media which store said content key.

25. The method of claim 22 wherein said content key is interspersed through different portions of said media.

26. The method of claim 25 wherein said content key is encoded as errors in an error correction code.

27. The method of claim 22 wherein said content key is a private key.

28. The method of claim 22 wherein said steps of receiving, validating, and sending are performed by a processor on an active portion of said media.

29. The method of claim 22 wherein the step of sending further comprises:

receiving an encrypted random number;

decrypting said random number; and

performing an exclusive-or (XOR) operation on said content key.