Protecting confidential data with transactional processing in execute-only memory

• US 9,665,373 B2
• Filed: 06/26/2015
• Issued: 05/30/2017
• Est. Priority Date: 06/26/2015
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Huntley, Barry E., Lemay, Michael, Durham, David M., Shanbhogue, Vedvyas, Sahita, Ravi L., Rajwar, Ravi
• Primary Examiner(s): Reza, Mohammad W
• Application Number:
  US14/752,079
• Publication Number:
  US 20160378490A1
• Time in Patent Office: 704 Days
• Field of Search: 713189
• CPC Class Codes: G06F 11/0745 in an input/output transactions management context input/output processing in general G06F13/00
• CPC Class Codes: G06F 11/0751 Error or fault detection not based on redundancy power supply failures G06F1/30; network fault management H04L41/06
• CPC Class Codes: G06F 9/3004 to perform operations on memory
• CPC Class Codes: G06F 9/30076 to perform miscellaneous control operations, e.g. NOP
• CPC Class Codes: G06F 9/30145 Instruction analysis, e.g. decoding, instruction word fields
• CPC Class Codes: G06F 9/30167 of immediate specifier, e.g. constants
• CPC Class Codes: G06F 9/30189 according to execution mode, e.g. mode flag
• CPC Class Codes: G06F 9/3802 Instruction prefetching

Abstract

Generally, this disclosure provides systems, devices, methods and computer readable media for protecting confidential data with transactional processing in execute-only memory. The system may include a memory module configured to store an execute-only code page. The system may also include a transaction processor configured to enforce a transaction region associated with at least a portion of the code page. The system may further include a processor configured to execute a load instruction fetched from the code page, the load instruction configured to load at least a portion of the confidential data from an immediate operand of the load instruction if a transaction mode of the transaction region is enabled.

Claims

1. A system for protecting confidential data, said system comprising:

a memory module to store an execute-only code page;

a transaction processor to enforce a transaction region associated with at least a portion of said code page; and

a processor to execute a load instruction fetched from said code page, said load instruction to load at least a portion of said confidential data from an immediate operand of said load instruction if a transaction mode of said transaction region is enabled.

2. The system of claim 1, further comprising a register associated with said processor, wherein said load instruction is to load said confidential data to said register.

3. The system of claim 1, wherein said processor is further to cause said load instruction to generate a fault if said transaction mode of said transaction region is not enabled.

4. The system of claim 1, wherein said processor is further to cause said load instruction to load a pre-determined constant, said constant unassociated with said confidential data, if said transaction mode of said transaction region is not enabled.

5. The system of claim 1, wherein said transaction processor is further to clear said loaded confidential data in response to an abort of said transaction mode.

6. The system of claim 1, wherein said portion of said confidential data is encoded in said immediate operand such that said encoded data represents at least a portion of a no-operation (NOP) instruction sequence of said processor.

7. The system of claim 1, wherein said processor is further to execute a check instruction to verify that execution is from said code page and to abort said transaction mode if said verification fails.

8. A method for protecting confidential data, said method comprising:

establishing a code page in memory, said code page restricted to execute-only access;

defining a transaction region associated with at least a portion of said code page; and

executing a load instruction located in said code page, said load instruction to load at least a portion of said confidential data from an immediate operand of said load instruction if a transaction mode of said transaction region is enabled.

9. The method of claim 8, wherein said load instruction is to load said confidential data to a register associated with a processor.

10. The method of claim 8, wherein said load instruction is to generate a fault if said transaction mode of said transaction region is not enabled.

11. The method of claim 8, wherein said load instruction is to load a pre-determined constant, said constant unassociated with said confidential data, if said transaction mode of said transaction region is not enabled.

12. The method of claim 8, further comprising clearing said loaded confidential data in response to an abort of said transaction mode.

13. The method of claim 8, further comprising clearing said loaded confidential data on exit of said transaction mode.

14. The method of claim 8, further comprising encoding said portion of said confidential data in said immediate operand such that said encoded data represents at least a portion of a no-operation (NOP) instruction sequence.

15. The method of claim 8, further comprising:

executing a pre-guard code segment before said load instruction, said pre-guard code segment to load a selected constant into a first location; and

executing a post-guard code segment after said load instruction, said post-guard code segment to load said selected constant into a second location and to verify that the content of said first and said second locations match.

16. The method of claim 8, further comprising executing a check instruction to verify that execution is from said code page and aborting said transaction mode if said verification fails.

17. The method of claim 8, wherein said confidential data is an encryption key and said load instruction is dynamically generated based on information received over a secure network connection.

18. The method of claim 8, wherein at least a portion of said code page is encrypted.

19. At least one non-transitory computer-readable storage medium having instructions stored thereon which when executed by a processor result in the following operations for protecting confidential data, said operations comprising:

establishing a code page in memory, said code page restricted to execute-only access;

defining a transaction region associated with at least a portion of said code page; and

executing a load instruction located in said code page, said load instruction to load at least a portion of said confidential data from an immediate operand of said load instruction if a transaction mode of said transaction region is enabled.

20. The computer-readable storage medium of claim 19, wherein said load instruction is to load said confidential data to a register associated with a processor.

21. The computer-readable storage medium of claim 19, wherein said load instruction is to generate a fault if said transaction mode of said transaction region is not enabled.

22. The computer-readable storage medium of claim 19, wherein said load instruction is to load a pre-determined constant, said constant unassociated with said confidential data, if said transaction mode of said transaction region is not enabled.

23. The computer-readable storage medium of claim 19, further comprising clearing said loaded confidential data in response to an abort of said transaction mode.

24. The computer-readable storage medium of claim 19, further comprising clearing said loaded confidential data on exit of said transaction mode.

25. The computer-readable storage medium of claim 19, further comprising encoding said portion of said confidential data in said immediate operand such that said encoded data represents at least a portion of a no-operation (NOP) instruction sequence.

26. The computer-readable storage medium of claim 19, further comprising:

executing a pre-guard code segment before said load instruction, said pre-guard code segment to load a selected constant into a first location; and

executing a post-guard code segment after said load instruction, said post-guard code segment to load said selected constant into a second location and to verify that the content of said first and said second locations match.

27. The computer-readable storage medium of claim 19, further comprising executing a check instruction to verify that execution is from said code page and aborting said transaction mode if said verification fails.

28. The computer-readable storage medium of claim 19, wherein said confidential data is an encryption key and said load instruction is dynamically generated based on information received over a secure network connection.