Software self-checking systems and methods

• US 9,141,788 B2
• Filed: 04/28/2014
• Issued: 09/22/2015
• Est. Priority Date: 06/13/2001
• Status: Active Grant

• Current Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Original Assignee: Intertrust Technologies Corporation (Fidelio Acquisition Co LLC)
• Inventors: Horne, William G., Matheson, Lesley R., Sheehan, Casey, Tarjan, Robert E.
• Primary Examiner(s): Song, Hosuk
• Application Number:
  US14/263,650
• Publication Number:
  US 20150067837A1
• Time in Patent Office: 512 Days
• Field of Search: 713/176, 713/181, 713/187, 726/22, 726 26- 27, 714/37
• US Class Current: 1/1
• CPC Class Codes: G06F 11/3624 by performing operations on the source code, e.g. via a compiler
• CPC Class Codes: G06F 21/52 during program execution, e.g. stack integrity ; Preventing unwanted data erasure; Buffer overflow
• CPC Class Codes: G06F 21/54 by adding security routines or objects to programs
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: G06F 2221/2149 Restricted operating environment
• CPC Class Codes: G06F 3/0623 in relation to content
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0673 Single storage device

Abstract

Software self-checking mechanisms are described for improving software tamper resistance and/or reliability. Redundant tests are performed to detect modifications to a program while it is running. Modifications are recorded or reported. Embodiments of the software self-checking mechanisms can be implemented such that they are relatively stealthy and robust, and so that it they are compatible with copy-specific static watermarking and other tamper-resistance techniques.

Claims

1. A non-transitory computer-readable storage medium, the computer-readable storage medium storing programming instructions that, if executed by a processor of a computer system, are operable to cause the computer system to perform operations comprising:

calculating, by a self-checking code sequence included in a program, during execution of the program, a result of a function based on a portion of the program;

comparing, by the self-checking code sequence, the result with a predefined value;

determining, by the self-checking code sequence, that the result does not match a predefined value based on the comparison; and

triggering a tamper response mechanism based on the determination that the result does not match the predefined value.

2. The non-transitory computer-readable storage medium of claim 1, wherein the self-checking code sequence comprises a first self-checking code sequence of a plurality of self-checking code sequences.

3. The non-transitory computer-readable storage medium of claim 2, wherein the portion of the program comprises a first portion of a plurality of portions of the program.

4. The non-transitory computer-readable storage medium of claim 3, wherein each portion of the plurality of portions comprises at least one corrector value.

5. The non-transitory computer-readable storage medium of claim 3, wherein the plurality of portions of the program overlap at least in part.

6. The non-transitory computer-readable storage medium of claim 3, wherein the self-checking code sequence is included in the first portion of the program.

7. The non-transitory computer-readable storage medium of claim 3, wherein the self-checking code sequence is included in a second portion of the program different, at least in part, from the first portion.

8. The non-transitory computer-readable storage medium of claim 5, wherein each self-checking code sequence of the plurality of self-checking code sequences is associated with a portion of the plurality of portions of the program in a relatively random fashion.

9. The non-transitory computer-readable storage medium of claim 3, wherein the first self-checking code sequence is configured to check the integrity of at least one other self-checking code sequence of the plurality of self-checking code sequences.

10. The non-transitory computer-readable storage medium of claim 3, wherein the plurality of self-checking code sequences are distributed in a relatively uniform fashion throughout the program.

11. The non-transitory computer-readable storage medium of claim 1, wherein the function comprises a hash function.

12. The non-transitory computer-readable storage medium of claim 11, wherein the hash function is invertible.

13. The non-transitory computer-readable storage medium of claim 11, wherein the hash function is relatively lightweight.

14. The non-transitory computer-readable storage medium of claim 1, wherein triggering the tamper response mechanism comprises terminating execution of the program.

15. The non-transitory computer-readable storage medium of claim 1, wherein triggering the tamper response mechanism comprises disabling a function of the program.

16. The non-transitory computer-readable storage medium of claim 1, wherein triggering the tamper response mechanism comprises terminating the ability of the program to access protected data.

17. The non-transitory computer-readable storage medium of claim 1, wherein triggering the tamper response mechanism comprises generating and transmitting a message to a system administrator.