Access control method and device in an embedded system

• US 7,363,293 B2
• Filed: 12/11/2002
• Issued: 04/22/2008
• Est. Priority Date: 12/12/2001
• Status: Expired due to Term

• Current Assignee: Axalto S A
• Original Assignee: Axalto S A
• Inventors: Marchetaux, Jean-Claude, Siegelin, Christoph, Boudou, Alain
• Primary Examiner(s): PANNALA, SATHYANARAYA R
• Application Number:
  US10/497,738
• Publication Number:
  US 20050005079A1
• Time in Patent Office: 1,959 Days
• Field of Search: 711/146, 711/172, 711/206, 345/424, 707 1- 4
• US Class Current: 1/1
• CPC Class Codes: G06F 12/1441 for a range
• CPC Class Codes: G06F 12/1483 using an access-table, e.g. matrix or list

Abstract

A method and device to control the access to a data memory space of a computer system by an active process stored in a program space of the system. When the active process attempts to perform an operation on a part of the data memory space the method or device controls the access to the part of the data memory space by comparing a dynamic attribute linked to the active process to an attribute linked to the part of the data memory space the process is attempting access. The value of the dynamic attribute is updated according to the present and previous status of the active process.

Claims

1. An access control method for parts of a memory space of a computer system by an active process stored in a program memory space of said computer system, said active process performing an operation on said parts of the memory space, wherein the method comprises:

controlling the access to at least one part of the memory space via a dynamic attribute linked to said active process;

updating the value of the dynamic attribute according to the present and previous status of the active process;

comparing an attribute linked to the target part of the memory space with the dynamic attribute linked to the active process;

accepting the operation in response to the comparison indicating satisfaction of an acceptance criteria between the attribute linked to the targeted part of the memory space and the dynamic attribute linked to the active process; and

rejecting the operation in response to the comparison indicating failure of an acceptance criteria between the attribute linked to the targeted part of the memory space and the dynamic attribute linked to the active process.

2. The access control method according to claim 1, further comprising:

chaining inter-module call; and

wherein the acceptance criteria comprises determining that the targeted memory space corresponds to a part of the memory space corresponding to at least one module in an inter-module chain of modules.

3. The access control method according to claim 1, wherein the dynamic-attribute is a stack including each module in a chain of modules from a chaining of inter-module calls having a most recently called module on top of the stack, and wherein the comparing step comprises determining whether the at least one part of the targeted memory space is in a data space corresponding to a module at the top of the stack.

4. The access control method according to claim 1, wherein the dynamic attribute is a list including each module in a chain of modules from a chaining of inter-module calls, and wherein the comparing step comprises determining whether the at least one part of the targeted memory space is in a data space corresponding to a module in said list.

5. The access control method according to claim 1, wherein the updating step comprises:

checking the identity and the rights of a module being part of the active process;

explicitly requesting the update of the dynamic attribute; and

making said update if the module is authorised to update the dynamic attribute.

6. The access control method of claim 1 wherein the step of accepting or rejecting the access to said at least one part of the memory space further comprises accepting or rejecting access to said at least one part of the memory space according to the type of operation.

7. The access control method of claim 1 wherein at least one of the steps of accepting and rejecting the access to said at least one part of the memory space further comprises, respectively, accepting or rejecting access to said at least one part of the memory space according to predefined rules.

8. The access control method according to claim 1, wherein said method further comprises managing said update by checking the identity and the rights of a module being part of the active process and implicitly updating the dynamic attribute and making said update if the module is authorised to update the dynamic attribute.

9. A programmable storage media having computer program instructions for causing a data processing system to execute an access control method for parts of a data memory space, the program instructions comprising to cause the data processing system to:

control the access to at least one part of the memory space via a dynamic attribute linked to said active process;

update the value of the dynamic attribute according to the present and previous status of the active process;

compare an attribute linked to the target part of the memory space with the dynamic attribute linked to the active process;

accept the operation in response to the comparison indicating satisfaction of an acceptance criteria between the attribute linked to the targeted part of the memory space and the dynamic attribute linked to the active process; and

reject the operation in response to the comparison indicating failure of an acceptance criteria between the attribute linked to the targeted part of the memory space and the dynamic attribute linked to the active process.

10. The programmable storage media having computer program instructions for causing a data processing system to execute an access control method according to claim 9, wherein said acceptance criteria comprises determining that the targeted memory space corresponds to a part of the memory space corresponding to at least one module in an inter-module chain of modules.

11. The programmable storage media having computer program instructions for causing a data processing system to execute an access control method according to claim 9, wherein the dynamic-attribute is a stack including each module in a chain of modules from a chaining of inter-module calls having a most recently called module on top of the stack, and wherein instructions to compare comprises determining whether the at least one part of the targeted memory space is in a data space corresponding to a module at the top of the stack.

12. The programmable storage media having computer program instructions for causing a data processing system to execute an access control method according to claim 9, wherein the dynamic attribute is a list including each module in a chain of modules from a chaining of inter-module calls, and wherein instructions to compare comprises determining whether the at least one part of the targeted data memory space is in a data space corresponding to a module in said list.

13. The programmable storage media having computer program instructions for causing a data processing system to execute an access control method according to claim 9, wherein the instructions to updated comprises instructions to cause the data processing system to:

check the identity and the rights of a module being part of the active process;

request the update of the dynamic attribute; and

make said update only if the module is authorised to update the dynamic attribute.