System and method for data processing by executing a security program routine initially stored in a protected part of irreversibly blocked memory upon start-up

• US 6,857,068 B1
• Filed: 06/21/2000
• Issued: 02/15/2005
• Est. Priority Date: 06/25/1999
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Smeets, Ben, Möller, Bernd, Osthoff, Harro, Poon, Kar-Fat
• Primary Examiner(s): Browne, Lynne H.
• Assistant Examiner(s): PATEL, NITIN C
• Application Number:
  US09/598,173
• Time in Patent Office: 1,700 Days
• Field of Search: 713/1, 713/2, 713/100, 713/151, 713/182, 713/183, 713/200, 380/247, 380/249, 380/255, 711/1, 711/152, 711/163
• US Class Current: 713/2
• CPC Class Codes: G06F 12/1433 for a module or a part of a module
• CPC Class Codes: G06F 21/79 in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 9/4401 Bootstrapping security arrangements therefor G06F21/57
• CPC Class Codes: G06F 9/468 Specific access rights for resources, e.g. using capability register

Abstract

Device for processing data includes a processor for executing program routines, and a memory for storing program routines to be executed by the processor. Part of the memory includes a protected part from which data can be read but which is protected against being written into. The processor is arranged to necessarily execute a program routine stored in the protected part of the memory upon start-up.

Claims

1. Device for processing data, comprising:

a processor for executing program routines, and a memory for storing program routines to be executed by said processor, where

at least a part of said memory is arranged as a protected part from which data can be read but which is protected against being written into, where said protected part is arranged such that a mechanism is provided such that after data is initially stored in said protected part, any subsequent writing of data into said protected part is irreversibly blocked, and

said processor is arranged to necessarily execute a security program routine stored in said protected part of said memory upon start-up.

2. Device according to claim 1, wherein said processor stores permanent start addresses that are necessarily called upon start-up of said processor, where at least one of said start addresses points to said protected part of said memory.

3. Device according to claim 1, wherein said protected part of said memory is a first part, and said memory further comprises a second part into which data can be written, where the security program routine from said protected part executed by said processor upon start-up comprises checking for changes in at least a part of the data contained in said second part.

4. Device according to claim 3, wherein said security program routine from said protected part executed by said processor upon start-up comprises calculating a characteristic parameter for data being checked for changes, and comparing said characteristic parameter with a value stored in said second part of said memory at the time of writing said data being checked for changes into said second part of said memory.

5. Device according to claim 4, wherein said characteristic parameter is a check sum.

6. Device according to claim 1, wherein said memory comprises a plurality of memory devices, one of which comprises said protected part, and the rest of which are arranged such that data may be written into them.

7. Device according to claim 1, wherein said protected area is arranged such that the process for storing data therein comprises:

writing data into said protected part via a write line, and

sending a signal to said protected part in response to which said write line is permanently interrupted.

8. Device according to claim 7, wherein said write line is a fusable link.

9. Device according to claim 1, wherein said memory comprises a finite state machine, said finite state machine defining a state which protects said protected part from being written into.

10. Device according to claim 1, wherein said memory comprise one or more of an EEPROM, a flash memory device, and a flash memory device emulating an EEPROM.

11. Device according to claim 1, wherein said memory comprises a memory chip having electrical contacts for being connected with a circuit board that are arranged such that said electrical contacts are covered by said memory chip when said memory chip is mounted on said circuit board.

12. Device according to claim 11, wherein said electrical contacts are provided in a ball-grid-array.

13. Communication device comprising a device for processing data according to claim 1.

14. Communication device according to claim 13, wherein said communication device is a mobile telephone.

15. Communication device according to claim 13, wherein said communication device is a bluetooth communication device.

16. Method for controlling a data processing device having a processor for executing program routines and a memory for storing program routines to be executed by said processor, comprising:

arranging at least a part of said memory as a protected part from which data can be read but which is protected against being written into;

after data is initially stored in said protected part, irreversibly blocking any subsequent writing of data into said protected part; and

said processor necessarily executing a security program routine stored in said protected part of said memory upon start-up.

17. Method according to claim 16, wherein said processor stores permanent start addresses that are necessarily called upon start-up of said processor, where at least one of said start addresses points to said protected part of said memory.

18. Method according to claim 16, wherein said protected part of said memory is a first part, and said memory further comprises a second part into which data can be written, where the security program routine from said protected part executed by said processor upon start-up comprises checking for changes in at least a part of the data contained in said second part.

19. Method according to claim 18, wherein said security program routine from said protected part executed by said processor upon start-up comprises calculating a characteristic parameter for data being checked for changes, and comparing said characteristic parameter with a value stored in said second part of said memory at the time of writing said data being checked for changes into said second part of said memory.

20. Method according to claim 19, wherein said characteristic parameter is a check sum.

21. Method according to claim 16, wherein said memory comprises a plurality of memory devices, one of which comprises said protected part, and the rest of which are arranged such that data may be written into them.

22. Method according to claim 16, wherein said protected area is arranged such that the process for storing data therein comprises:

writing data into said protected part via a write line, and

sending a signal to said protected part in response to which said write line is permanently interrupted.

23. Method according to claim 22, wherein said write line is a fusable link.

24. Method according to claim 16, wherein said memory comprises a finite state machine, said finite state machine defining a state which protects said protected part from being written into.

25. Method according to claim 16, wherein said memory comprises one or more of an EEPROM, a flash memory device, and a flash memory device emulating an EEPROM.

26. Method according to claim 16, wherein said memory comprises a memory chip having electrical contacts for being connected with a circuit board that are arranged such that said electrical contacts are covered by said memory chip when said memory chip is mounted on said circuit board.

27. Method according to claim 26, wherein said electrical contacts are provided in a ball-grid-array.

28. A medium readable by a data processing device, having a program recorded thereon, where the program is to make the data processing device execute the method of claim 16.