Reprogrammable security for controlling piracy and enabling interactive content

• US 20080137848A1
• Filed: 10/31/2007
• Published: 06/12/2008
• Est. Priority Date: 07/07/2003
• Status: Active Grant

• Current Assignee: Irdeto USA Incorporated (MultiChoice Group Ltd.)
• Original Assignee: Cryptography Research, Inc. (Rambus Inc.)
• Inventors: Laren, Carter C., Kocher, Paul C., Lawson, Nathaniel J., Jun, Benjamin C., Pearson, Peter K., Jaffe, Joshua M.
• Granted Patent: US 8,131,646 B2
• Time in Patent Office: Days
• US Class Current: 380/201
• 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 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: G06F 9/445 Program loading or initiating bootstrapping G06F9/4401; security arrangements for program loading or initiating G06F21/57
• CPC Class Codes: G06Q 50/188 Electronic negotiation
• 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 20/00115 wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00231 wherein the key is obtained from a local external medium, e.g. a card
• CPC Class Codes: G11B 20/00246 wherein the key is obtained from a local device, e.g. device key initially stored by the player or by the recorder
• CPC Class Codes: G11B 20/00253 wherein the key is stored on the record carrier
• CPC Class Codes: G11B 20/00449 content scrambling system [CSS]
• CPC Class Codes: G11B 20/00818 wherein the usage restriction limits the signal quality, e.g. by low-pass filtering of audio signals or by reducing the resolution of video signals
• CPC Class Codes: G11B 20/00884 involving a watermark, i.e. a barely perceptible transformation of the original data which can nevertheless be recognised by an algorithm
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 9/0844 with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys
• CPC Class Codes: H04L 9/302 involving the integer factorization problem, e.g. RSA or quadratic sieve [QS] schemes
• CPC Class Codes: H04L 9/3236 using cryptographic hash functions
• CPC Class Codes: H04L 9/3249 using RSA or related signature schemes, e.g. Rabin scheme
• CPC Class Codes: H04L 9/3271 using challenge-response
• CPC Class Codes: H04N 2005/91342 : the copy protection signal being an authentication signal
• CPC Class Codes: H04N 2005/91364 : the video signal being scrambled
• CPC Class Codes: H04N 21/4181 : for conditional access
• CPC Class Codes: H04N 21/42646 : for reading from or writing on a non-volatile solid state storage medium, e.g. DVD, CD-ROM
• CPC Class Codes: H04N 21/4325 : by playing back content from the storage medium reproduction of recorded television signals H04N5/76; reproduction of recorded television signals H04N9/79
• CPC Class Codes: H04N 21/4405 : involving video stream decryption
• 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 21/8193 : dedicated tools, e.g. video decoder software or IPMP tool
• CPC Class Codes: H04N 21/8358 : involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection

Abstract

Technologies are disclosed to transfer responsibility and control over security from player makers to content authors by enabling integration of security logic and content. An exemplary optical disc carries an encrypted digital video title combined with data processing operations that implement the title'"'"'s security policies and decryption processes. Player devices include a processing environment (e.g., a real-time virtual machine), which plays content by interpreting its processing operations. Players also provide procedure calls to enable content code to load data from media, perform network communications, determine playback environment configurations, access secure nonvolatile storage, submit data to CODECs for output, and/or perform cryptographic operations. Content can insert forensic watermarks in decoded output for tracing pirate copies. If pirates compromise a player or title, future content can be mastered with security features that, for example, block the attack, revoke pirated media, or use native code to correct player vulnerabilities.

Claims

1. A method of distributing audiovisual content intended for secure playback, comprising:

(a) modifying at least a portion of the audiovisual content to thereby corrupt the video;

(b) generating program logic associated with the modified content, the program logic adapted to correct a modification applied in step (a);

(c) distributing the modified content; and

(d) distributing the program logic.

2. The method of claim 1 where:

(a) steps (c) and (d) are performed together by distributing the modified content and program logic on a common optical disc; and

(b) generating program logic includes generating program logic further adapted to interrogate playback environment.

3. The method of claim 1 where generating program logic includes generating program logic adapted to apply one of a plurality of substitutions to correct modification of said video, said substitution being selected based on information characterizing said playback device.

4. The method of claim 1 where:

(a) said method further comprises encrypting at least a portion of said program logic with a key derived using at least one key associated with a specific playback device seeking to play content; and

(b) distributing said program logic includes distributing any portions thereof which have been encrypted using at least one key associated with said specific playback device.

5. The method of claim 1 further comprising:

(a) configuring the program logic to accept information from a user; and

(b) configuring the program logic to use said information to derive a key necessary for correcting modification of said audiovisual content.

6. The method of claim 1 further comprising configuring the program logic to cause a player device to access a server over a network.

7. The method of claim 1 further comprising configuring the program logic to determine whether a countermeasure is to be applied to playback environment, by:

(a) identifying at least one characteristic of playback environment;

(b) using said characteristic to determine whether a countermeasure is to be applied to the playback environment; and

(c) if a countermeasure is to be applied to the playback environment, executing said countermeasure before correcting modification.

8. The method of claim 7 where the program logic is configured to access over a network a database that matches at least one characteristic to an indication of whether a countermeasure is to be applied, and to download said countermeasure.

9. The method of claim 7 where the program logic is further configured to access non-volatile memory of a playback device.

10. An apparatus comprising program logic stored on machine-readable media, said program logic adapted for distribution in connection with audiovisual content that had been at least in part degraded in quality, said program logic adapted to:

(a) identify at least one characteristic of playback environment associated with a playback device seeking to play the content;

(b) determine whether the at least one characteristic reflects a valid playback device, with playback device validity determined by at least one of (i) authenticating playback device manufacturer, (ii) authenticating player device model, (iii) authenticating player device firmware, and (iv) determining that playback environment does not reflect a predetermined security; and

(c) process the content to restore level of quality if the at least one characteristic reflects a valid playback device.

11. The apparatus of claim 10 further comprising modified content stored together with said program logic on a common optical disc.

12. The apparatus of claim 10 where the program logic is adapted to restore content to one of a plurality of said non-degraded states, with state selection being based on information characterizing said playback device.

13. The apparatus of claim 10 where at least a portion of program logic is encrypted with a key derived using at least one key associated with a playback device.

14. The apparatus of claim 10 where the program logic is configured to:

(a) accept information from a user; and

(b) use the information to derive a key necessary for the decoding of audiovisual content.

15. The apparatus of claim 14 where the program logic is configured to cause a player device to access a server over a network.

16. The apparatus of claim 10 where the program logic is configured to determine whether a countermeasure is to be applied to playback environment, by:

(a) identifying at least one characteristic of playback environment;

(b) using said characteristic to determine whether a countermeasure is to be applied to the playback environment; and

(c) if said countermeasure is to be applied to the playback environment, executing said countermeasure before correcting modification.

17. The apparatus of claim 16 where the program logic is configured to access over a network a database that matches at least one characteristic to an indication of whether a countermeasure is to be applied, and to download said associated countermeasure.

18. The apparatus of claim 16 where the program logic is further configured to access non-volatile memory of a playback device.

19. A method for verifying the integrity of encrypted audiovisual content on an optical medium, comprising:

(a) performing hashes of portions of said encrypted audiovisual content;

(b) creating a hash tree from said hashes by hashing multiple of said hashes together; and

(c) digitally signing said hash tree such that said signature can be verified by a playback device seeking to playback said audiovisual content.