Methods of attack on a content screening algorithm based on adulteration of marked content

• US 20020144133A1
• Filed: 09/28/2001
• Published: 10/03/2002
• Est. Priority Date: 03/29/2001
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Epstein, Michael A., Krasinski, Raymond
• Granted Patent: US 6,976,173 B2
• Time in Patent Office: Days
• US Class Current: 713/189
• 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: G06T 1/0021 Image watermarking
• CPC Class Codes: G11B 19/122 involving the detection of an identification or authentication mark record carriers indicating unauthorised or prior use G11B23/28
• 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 20/00768 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
• CPC Class Codes: H04L 2463/103 applying security measure for protecting copyright
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources

Abstract

Methods and apparatus for attacking a screening algorithm. The methods include the steps of marking content to be downloaded, inserting at least one section of legitimate content into the marked content, and subjecting the content to a screening algorithm. The screening algorithm may include the steps of determining a number of segments that are included within the content, selecting at least two segments within the content, screening the two segments to determine whether the two segments verify correctly through the screening algorithm, and downloading the content when it is determined that the two segments verify correctly through the screening algorithm. Once the content has been successfully downloaded, the integrity of the downloaded content may be restored by removing the legitimate content that was previously inserted into the downloaded content.

Claims

1. A method of attacking a screening algorithm, the method comprising the steps of:

marking content to be downloaded;

inserting at least one section of legitimate content into the marked content; and

subjecting the marked content, having the at least one section of legitimate content inserted therein, to a screening algorithm.

2. The method of attacking a screening algorithm as recited in claim 1 wherein the screening algorithm is a Secure Digital Music Initiative screening algorithm.

3. The method of attacking a screening algorithm as recited in claim 1 wherein the screening algorithm relies on a sampling of data contained within the marked content.

4. The method of attacking a screening algorithm as recited in claim 1 wherein the marked content is downloaded from the Internet.

5. The method of attacking a screening algorithm as recited in claim 1 further comprising the step of writing the downloaded content to a memory device.

6. The method of attacking a screening algorithm as recited in claim 1 further comprising the step of restoring the integrity of the marked content by removing the legitimate content inserted into the marked content.

7. The method of attacking a screening algorithm as recited in claim 1 wherein the screening process includes the step of determining a number of segments of a predetermined duration of time which are included within the marked content having the at least one section of legitimate content inserted therein.

8. The method of attacking a screening algorithm as recited in claim 7 wherein the screening process further includes the steps of selecting at least two segments within the marked content;

screening the at least two segments to determine whether the at least two segments verify correctly through the screening algorithm; and

downloading the marked content when it is determined that the at least two segments verify correctly through the screening algorithm.

9. The method of attacking a screening algorithm as recited in claim 7 wherein the predetermined duration of time is fifteen seconds.

10. The method of attacking a screening algorithm as recited in claim 1 wherein the at least one section of legitimate content inserted into the marked content is a section of silence.

11. An apparatus for attacking a screening algorithm comprising:

a processor device for marking content to be downloaded and for inserting at least one section of legitimate content into the marked content, wherein the marked content having at least one section of legitimate content therein is subjected to a screening algorithm.

12. The apparatus for attacking a screening algorithm as recited in claim 11, further comprising:

a memory device associated with the processor device storing the content when the content passes through the screening algorithm.

13. The apparatus for attacking a screening algorithm as recited in claim 11, wherein the screening algorithm relies on a sampling of data contained within the marked content.

15. The article of manufacture for attacking a screening algorithm as recited in claim 14 wherein the screening algorithm is a Secure Digital Music Initiative screening algorithm.

16. The article of manufacture for attacking a screening algorithm as recited in claim 14 wherein the screening algorithm relies on a sampling of data contained within the marked content.

17. The article of manufacture for attacking a screening algorithm as recited in claim 14 further comprising the step of writing the downloaded content to a memory device.

18. The article of manufacture for attacking a screening algorithm as recited in claim 14 further comprising the step of restoring the integrity of the marked content by removing the legitimate content inserted into the marked content.

19. The article of manufacture for attacking a screening algorithm as recited in claim 14 wherein the screening process includes the step of determining a number of segments of a predetermined duration of time which are included within the marked content having the at least one section of legitimate content inserted therein.

20. The article of manufacture for attacking a screening algorithm as recited in claim 19 wherein the screening process further includes the steps of selecting at least two segments within the marked content;

screening the at least two segments to determine whether the at least two segments verify correctly through the screening algorithm; and

downloading the marked content when it is determined that the at least two segments verify correctly through the screening algorithm.

14. An article of manufacture for attacking a screening algorithm, the article comprising a machine readable medium containing one or more programs which when executed implement the steps of:

marking content to be downloaded;

inserting at least one section of legitimate content into the marked content; and

subjecting the marked content, having the at least one section of legitimate content inserted therein, to a screening algorithm.