Systems and methods for watermarking software and other media

• US 9,659,157 B2
• Filed: 05/02/2016
• Issued: 05/23/2017
• Est. Priority Date: 07/29/1999
• Status: Expired due to Fees

• Current Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Original Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Inventors: Horne, William G., Tarjan, Robert E., Maheshwari, Umesh, Sibert, W. Olin, Horning, James J., Matheson, Lesley R., Wright, Andrew K., Owicki, Susan S.
• Primary Examiner(s): Najjar, Saleh
• Assistant Examiner(s): ALMEIDA, DEVIN E
• Application Number:
  US15/144,145
• Publication Number:
  US 20160342778A1
• Time in Patent Office: 386 Days
• CPC Class Codes: G06F 11/3604 Software analysis for verifying properties of programs byte-code verification G06F9/44589
• CPC Class Codes: G06F 16/245 Query processing
• CPC Class Codes: G06F 21/16 Program or content traceability, e.g. by watermarking
• CPC Class Codes: G06N 7/01 Probabilistic graphical models, e.g. probabilistic networks
• CPC Class Codes: G09C 5/00 Ciphering apparatus or methods not provided for in the preceding groups, e.g. involving the concealment or deformation of graphic data such as designs, written or printed messages
• CPC Class Codes: H04K 1/00 Secret communication
• CPC Class Codes: H04K 1/02 by adding a second signal to make the desired signal unintelligible
• CPC Class Codes: H04L 2209/608 Watermarking
• CPC Class Codes: H04L 9/3226 using a predetermined code, e.g. password, passphrase or PIN network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

Systems and methods are disclosed for embedding information in software and/or other electronic content such that the information is difficult for an unauthorized party to detect, remove, insert, forge, and/or corrupt. The embedded information can be used to protect electronic content by identifying the content'"'"'s source, thus enabling unauthorized copies or derivatives to be reliably traced, and thus facilitating effective legal recourse by the content owner. Systems and methods are also disclosed for protecting, detecting, removing, and decoding information embedded in electronic content, and for using the embedded information to protect software or other media from unauthorized analysis, attack, and/or modification.

Claims

1. A method for watermarking computer code, the method performed by a computer system comprising a processor and a memory encoded with program instructions that, when executed by the processor, cause the system to perform the method, the method comprising:

statistically analyzing the computer code to generate a probabilistic state model relating to sequences of operation codes included in the computer code, wherein the analyzing comprises;

analyzing the computer code to identify a first operation code included in the computer code;

analyzing the computer code to identify a second operation code included in the computer code; and

determining a probability that the first operation code is followed by the second operation code within the computer code;

generating one or more statistical models of the computer code based on the probabilistic state model;

generating at least one watermark based on the one or more statistical models of the computer code; and

inserting the at least one watermark into the computer code.

2. The method of claim 1, wherein the method further comprises:

prior to inserting the at least one watermark, accepting the at least one watermark for insertion based on the one or more statistical models of the computer code.

3. The method of claim 1, wherein statistically analyzing the computer code further comprises:

analyzing the computer code to determine a number of times each of a plurality of operation codes are included in the computer code;

identifying a plurality of common operation codes based on the determined number of times each of the plurality of operation codes are included in the computer code; and

generating the statistical model based on the identified plurality of common operation codes.

4. The method of claim 3, wherein generating the at least one watermark is further based on at least one operation code of the plurality of common operation codes.

5. The method of claim 1, wherein the probabilistic state model comprises a first node associated with the first operation code, a second node associated with the second operation code, and an edge associated with the determined probability that the first operation code is followed by the second operation code within the computer code.

6. The method of claim 1, wherein inserting the at least one watermark comprises inserting the at least one watermark into inert code included in the computer code.

7. The method of claim 1, wherein inserting the at least one watermark comprises inserting the at least one watermark into unused code included in the computer code.

8. The method of claim 1, wherein inserting the at least one watermark comprises identifying unused code included in the computer code and replacing the unused code with the watermark.

9. The method of claim 1, wherein the at least one watermark comprises inert code.

10. The method of claim 1, wherein generating the at least one watermark is further based on a plurality of watermark primitives.

11. A method for watermarking a first computer code, the method performed by a computer system comprising a processor and a memory encoded with program instructions that, when executed by the processor, cause the system to perform the method, the method comprising:

statistically analyzing a second computer code to generate a probabilistic state model relating to sequences of operation codes included in the second computer code, where the analyzing comprises;

analyzing the second computer code to identify a first operation code included in the second computer code;

analyzing the second computer code to identify a second operation code included in the second computer code; and

determining a probability that the first operation code is followed by the second operation code within the second computer code;

generating one or more statistical models of the second computer code based on the probabilistic state model;

generating at least one watermark based on the one or more statistical models of the second computer code; and

inserting the at least one watermark into the first computer code.

12. The method of claim 11, wherein the first computer code is different, at least in part, than the second computer code.

13. The method of claim 11, wherein the first computer code is identical to the second computer code.

14. The method of claim 11, wherein the method further comprises:

prior to inserting the at least one watermark, accepting the at least one watermark for insertion based on the one or more statistical models of the second computer code.

15. The method of claim 11, wherein statistically analyzing the computer code further comprises:

analyzing the second computer code to determine a number of times each of a plurality of operation codes are included in the second computer code;

identifying a plurality of common operation codes based on the determined number of times each of the plurality of operation codes are included in the second computer code; and

generating the statistical model based on the identified plurality of common operation codes.

16. The method of claim 15, wherein generating the at least one watermark is further based on at least one operation code of the plurality of common operation codes.

17. The method of claim 11, wherein inserting the at least one watermark comprises inserting the at least one watermark into unused code included in the first computer code.

18. The method of claim 11, wherein inserting the at least one watermark comprises identifying unused code included in the first computer code and replacing the unused code with the watermark.

19. The method of claim 11, wherein the at least one watermark comprises inert code.

20. The method of claim 11, wherein generating the at least one watermark is further based on a plurality of watermark primitives.