METHOD OF PROTECTING A PASSWORD FROM UNAUTHORIZED ACCESS AND DATA PROCESSING UNIT

• US 20090083858A1
• Filed: 09/26/2007
• Published: 03/26/2009
• Est. Priority Date: 09/26/2007
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Infineon Technologies AG
• Inventors: Knight, Richard, Goedecke, Michael, Barstow, John, Eder, Patrik, JENNINGS, David
• Granted Patent: US 8,239,963 B2
• Time in Patent Office: Days
• US Class Current: 726/27
• CPC Class Codes: G06F 21/34 involving the use of external additional devices, e.g. dongles or smart cards
• CPC Class Codes: G06F 21/6209 to a single file or object, e.g. in a secure envelope, encrypted and accessed using a key, or with access control rules appended to the object itself

Abstract

A method of protecting a password from unauthorized access and a data processing unit are provided. An embodiment of the method of protecting a password from unauthorized access comprises storing data representing at least a portion of a password in a memory, assigning the data to at least one of a plurality of instructions, storing the plurality of instructions as processor executable code in the memory, and preventing read-out of the processor executable code as data from the memory.

Claims

1. Method of protecting a password from unauthorized access, comprising:

storing data representing at least a portion of a password in a memory;

assigning the data to at least one of a plurality of instructions;

storing the plurality of instructions as processor executable code in the memory; and

preventing read-out of the processor executable code as data from the memory.

2. The method as recited in claim 1, further comprising:

allowing read-out of the processor executable code as code to be executed by a processor; and

allowing transfer of the allowably read-out processor executable code to a processor.

3. The method as recited in claim 1, further comprising storing the data as part of the processor executable code.

4. The method as recited in claim 1, further comprising building the data into at least one of the plurality of instructions.

5. The method as recited in claim 1, wherein the at least one of a plurality of instructions is an immediate instruction.

6. The method as recited in claim 1, further comprising executing the processor executable code to retrieve the data representing at least a portion of a password.

7. The method as recited in claim 1, wherein preventing read-out of the processor executable code as data from the memory includes controlling accesses to the memory or to a memory address range where the processor executable code is stored.

8. The method as recited in claim 1, wherein preventing read-out of the processor executable code as data from the memory includes limiting data read accesses accessing the memory or a memory address range where the processor executable code is stored.

9. The method as recited in claim 2, wherein allowing read-out of the processor executable code as code to be executed by a processor includes allowing instruction read accesses accessing the memory or a memory address range where the processor executable code is stored.

10. Method of protecting a password from unauthorized access, comprising:

distributing data representing at least a portion of a password into a plurality of data portions;

combining each of the data portions with at least one of a plurality of instructions;

storing the plurality of instructions including the combined data portions as processor executable code in a memory; and

preventing read-out of the processor executable code as data from the memory.

11. The method as recited in claim 10, further comprising:

allowing read-out of the processor executable code as code to be executed by a processor; and

allowing transfer of the allowably read-out processor executable code to a processor.

12. The method as recited in claim 10, wherein combining includes embedding each of the data portions in one of the plurality of instructions.

13. The method as recited in claim 10, further comprising executing the processor executable code to retrieve the data representing at least a portion of a password.

14. The method as recited in claim 10, further comprising distributing the combined data portions throughout the processor executable code.

15. Data processing unit comprising:

a memory to store data representing at least a portion of a password, the memory further to store a plurality of instructions as processor executable code;

a control unit to assign the data to at least one of the plurality of instructions; and

a circuit arrangement to prevent read-out of the processor executable code as data from the memory.

16. The data processing unit as recited in claim 15, the circuit arrangement further to allow read-out of the processor executable code as code to be executed by a processor;

and

the circuit arrangement further to allow transfer of the allowably read-out processor executable code to a processor.

17. The data processing unit as recited in claim 15, the memory further to store the data as part of the processor executable code.

18. The data processing unit as recited in claim 15, the control unit further to build the data into at least one of the plurality of instructions.

19. The data processing unit as recited in claim 15, wherein the at least one of a plurality of instructions is an immediate instruction.

20. The data processing unit as recited in claim 15, further comprising:

a processor to process instructions and having an instruction input port, the processor further to execute the processor executable code to retrieve the data representing at least a portion of a password when receiving the processor executable code via the instruction input port;

the circuit arrangement further to transfer the allowably read-out processor executable code to the instruction input port of the processor.

21. The data processing unit as recited in claim 15, the circuit arrangement further comprising a bus arrangement to couple the memory to a processor, the bus arrangement having a bus watching circuit to control accesses to the memory or to a memory address range where the processor executable code is stored.

22. Data processing unit comprising:

a control unit to distribute data representing at least a portion of a password into a plurality of data portions, the control unit further to combine each of the data portions with one of a plurality of instructions;

a memory to store the plurality of instructions including the combined data portions as processor executable code; and

a circuit arrangement to prevent read-out of the processor executable code as data from the memory.

23. The data processing unit as recited in claim 22, the circuit arrangement further to allow read-out of the processor executable code as code to be executed by a processor;

and

the circuit arrangement further to allow transfer of the allowably read-out processor executable code to a processor

24. The data processing unit as recited in claim 22, wherein the control unit is configured to embed each of the data portions in one of the plurality of instructions.

25. The data processing unit as recited in claim 22, further comprising:

a processor to process instructions, and having an instruction input port, and further to execute the processor executable code to retrieve the data representing at least a portion of a password when receiving the processor executable code via the instruction input port;

the circuit arrangement further to transfer the allowably read-out processor executable code to the instruction input port of the processor.