Computer-implemented method and system for embedding ancillary information into the header of a digitally signed executable

• US 8,397,072 B2
• Filed: 03/31/2006
• Issued: 03/12/2013
• Est. Priority Date: 05/20/2005
• Status: Active Grant

• Current Assignee: Rovi Solutions Corporation (Adeia Inc.)
• Original Assignee: Rovi Solutions Corporation (Adeia Inc.)
• Inventors: Torrubia, Andres M., Roman, Miguel A.
• Primary Examiner(s): Zand, Kambiz
• Assistant Examiner(s): Tran, Tongoc
• Application Number:
  US11/395,194
• Publication Number:
  US 20060265591A1
• Time in Patent Office: 2,538 Days
• Field of Search: 713/156, 713/160, 713/176, 713/156.16
• US Class Current: 713/176
• 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 21/16 Program or content traceability, e.g. by watermarking
• CPC Class Codes: G06F 21/51 at application loading time, e.g. accepting, rejecting, starting or inhibiting executable software based on integrity or source reliability
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures

Abstract

A computer-implemented method and system for embedding ancillary information into the header of a digitally signed executable are disclosed. The method and system include identifying a digital signature block and a digital signature size block in a digitally signed file header, modifying a digital signature size value in the digital signature size block, the modified value corresponding to the size of the digital signature block plus the length of an ancillary data block plus a pre-determined pad, storing the modified digital signature size in the digital signature size block, and appending the ancillary data block to the end of the digital signature block.

Claims

1. A method comprising:

identifying, by use of a processor, an existing digital signature block and an existing digital signature size block in a digitally signed file header;

modifying a digital signature size value in the digital signature size block, the modified value corresponding to the size of the digital signature block plus the length of an ancillary data block plus a pre-determined pad;

appending the ancillary data block to the end of the digital signature block, the modifying and appending being performed without invalidating an existing digital signature of the digitally signed file header; and

storing ancillary data in the ancillary data block.

2. The method as claimed in claim 1 further including recomputing a CRC value for the digitally signed file.

3. The method as claimed in claim 1 further including storing data in the pre-determined pad.

4. The method as claimed in claim 1 wherein the ancillary data includes a URL.

5. The method as claimed in claim 1 wherein the ancillary data includes a pricing information.

6. The method as claimed in claim 1 wherein the ancillary data includes digital rights management information.

7. The method as claimed in claim 1 wherein the ancillary data includes distribution network information.

8. The method as claimed in claim 1 wherein the ancillary data includes a timestamp.

9. The method as claimed in claim 1 wherein the ancillary data includes information identifying a product.

10. The method as claimed in claim 1 wherein the ancillary data includes information uniquely identifying the corresponding digitally signed file.

25. The method as claimed in claim 1 further including appending a pre-determined pad block to the end of the ancillary data block.

11. An article of manufacture embodied as a non-transitory machine-accessible medium including data that, when accessed by a machine, causes the machine to perform operations comprising:

identifying an existing digital signature block and an existing digital signature size block in a digitally signed file header;

modifying a digital signature size value in the digital signature size block, the modified value corresponding to the size of the digital signature block plus the length of an ancillary data block plus a pre-determined pad;

appending the ancillary data block to the end of the digital signature block, the modifying and appending being performed without invalidating an existing digital signature of the digitally signed file header; and

storing ancillary data in the ancillary data block.

12. The article of manufacture as claimed in claim 11 further including recomputing a CRC value for the digitally signed file.

13. The article of manufacture as claimed in claim 11 further including storing data in the pre-determined pad.

14. The article of manufacture as claimed in claim 11 wherein the ancillary data includes a URL.

15. The article of manufacture as claimed in claim 11 wherein the ancillary data includes a pricing information.

16. The article of manufacture as claimed in claim 11 wherein the ancillary data includes digital rights management information.

17. The article of manufacture as claimed in claim 11 wherein the ancillary data includes distribution network information.

18. The article of manufacture as claimed in claim 11 wherein the ancillary data includes a timestamp.

19. The article of manufacture as claimed in claim 11 wherein the ancillary data includes information identifying a product.

20. The article of manufacture as claimed in claim 11 wherein the ancillary data includes information uniquely identifying the corresponding digitally signed file.

26. The article of manufacture as claimed in claim 11 further including appending a pre-determined pad block to the end of the ancillary data block.

21. A method comprising:

identifying, by use of a processor, an existing CRC block in a digitally signed file header;

storing ancillary data associated with an index; and

modifying the CRC block in the digitally signed file header with the index value to retrieve ancillary data, the modifying being performed without invalidating an existing digital signature of the digitally signed file header.

22. The method as claimed in claim 21 wherein the ancillary data is stored on a server.

23. The method as claimed in claim 21 wherein the ancillary data is stored in local memory.

24. The method as claimed in claim 21 wherein the ancillary data is stored in a data storage device.