User defined function facility

• US 5,301,231 A
• Filed: 02/12/1992
• Issued: 04/05/1994
• Est. Priority Date: 02/12/1992
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hudson, John M., Stevens, James V., Henningsmeyer, Daniela, Johnson, Donald B., Matyas, Stephen M., Abraham, Dennis G., Le, An V.
• Primary Examiner(s): Gregory, Bernarr E.
• Application Number:
  US07/834,634
• Time in Patent Office: 783 Days
• Field of Search: 380/3, 380/4, 380/22, 380/23-25, 380/49, 380/50, 380/52, 235/379, 235/380
• US Class Current: 713/191
• CPC Class Codes: G06F 21/72 in cryptographic circuits
• CPC Class Codes: G06F 2207/7219 Countermeasures against side channel or fault attacks
• CPC Class Codes: G06F 9/30003 Arrangements for executing specific machine instructions

Abstract

In a cryptographic module, a User Defined Function (UDF) facility is provided which provides users with the capability of defining and creating custom functions to meet their cryptographic processing needs. The cryptographic module is contained within a physically and logically secure environment and comprises a processing unit and memory connected to the processing unit. The memory includes code for translating User Defined Functions (UDFs) into a machine-readable form and at least one command for operating on the UDFs. The UDFs are loaded into and executed in the secure area of the cryptographic module without compromising the total security of the transaction security system.

Claims

1. A cryptographic module for storing and operating on user defined cryptographic functions, said cryptographic module providing a physically and electrically secure environment, said user defined cryptographic functions including instructions arranged in a particular sequence to implement a desired cryptographic function, said cryptographic module comprising:

memory for storing said user defined cryptographic functions, said memory including;

code for translating said user defined cryptographic functions into a machine-executable form, and

code implementing at least one command for operating on said machine-executable form of said user defined cryptographic functions;

a processing unit connected to said memory for executing said code for translating said user defined cryptographic functions into a machine-executable form and for executing said code implementing at least one command for operating on said machine-executable form of said user defined cryptographic functions;

a physical protection device for protecting said cryptographic module from physical attack; and

an electrical protection device for protecting said cryptographic module from electrical attack.

2. The cryptographic module of claim 1 wherein said code for translating said user defined cryptographic functions into a machine-executable form includes an interpreter program.

3. The cryptographic module of claim 1 wherein said memory includes erasable programmable read only memory and random access memory.

4. The cryptographic module of claim 3 wherein said code for translating said user defined cryptographic functions into a machine-executable form is stored in said erasable programmable read only memory.

5. The cryptographic module of claim 4 wherein said code for translating said user defined cryptographic functions into a machine-executable form includes an interpreter program.

6. The cryptographic module of claim 3 wherein there is at least one executable cryptographic function stored in said erasable programmable read only memory.

7. The cryptographic module of claim 3 wherein there is at least one executable user defined cryptographic function stored in said random access memory.

8. The cryptographic module of claim 3 wherein said random access memory is non-volatile.

9. The cryptographic module of claim 1 wherein there is at least one executable cryptographic function stored in said memory.

10. The cryptographic module of claim 1 wherein there is at least one executable user defined cryptographic function stored in said memory.

11. The cryptographic module of claim 1 wherein said at least one command for operating on said machine-executable form of said user defined cryptographic functions is selected from the group of commands consisting of:

registering said user defined cryptographic functions in said memory,

loading said user defined cryptographic functions into said memory,

verifying that said user defined cryptographic functions have not been altered since they were registered in said memory,

deleting said user defined cryptographic functions form said memory,

invoking said user defined cryptographic functions, and

querying whether said user defined cryptographic functions have been registered in said memory.

12. The cryptographic module of claim 1 wherein said memory further includes code implementing a command for registering external objects in said memory.

13. The cryptographic module of claim 12 wherein said memory further includes code implementing a command for verifying that said external objects have not been altered since they were registered in said memory.

14. The cryptographic module of claim 12 wherein said memory further includes code implementing a command for deleting said external objects from said memory.

15. The cryptographic module of claim 12 wherein said memory further includes code implementing a command for querying whether said external objects have been registered in said memory.

16. The cryptographic module of claim 1 wherein said processing unit includes a cipher processor and a microprocessor.

17. The cryptographic module of claim 1 wherein there is memory contained outside of said physically and electrically secure environment connected to said processing unit.

18. The cryptographic module of claim 17 wherein said memory is random access memory.

19. The cryptographic module of claim 1 wherein said physical protection device includes an intrusion barrier for protecting against mechanical intrusion, chemical intrusion, temperature modification, and radiation exposure.

20. The cryptographic module of claim 1 wherein said electrical protection device includes electrical circuitry that prevents access to said memory while said processing unit is performing a read from said memory and that prevents access to said memory while said processing unit is executing an instruction which was not fetched from said memory.

21. The cryptographic module of claim 1 wherein there is a master key which is used by said user defined cryptographic functions to recover keys encrypted under said master key and wherein said master key is not available to said user defined cryptographic functions.

22. The cryptographic module of claim 1 wherein there is a cryptographic key which is utilized by said user defined cryptographic functions if a bit in a control vector associated with said cryptographic key is active and which is prevented from being utilized by said user defined cryptographic functions if said bit in said control vector associated with said cryptographic key is not active.

23. The cryptographic module of claim 1 wherein there are cryptographic keys and a control vector, said control vector including bits for use in separating cryptographic keys which are used in said user defined cryptographic functions and cryptographic keys which are used for other purposes.

24. A method of storing and operating on user defined cryptographic functions in a cryptographic module, the cryptographic module providing a physically and electrically secure environment, the user defined cryptographic functions including instructions arranged in a particular sequence to implement a desired cryptographic function, said method comprising the steps of:

storing the user defined cryptographic functions in memory in the cryptographic module;

translating the user defined cryptographic functions into a machine-executable form;

operating on the machine-executable form of the user defined cryptographic functions in the cryptographic module;

protecting the cryptographic module from physical attack; and

protecting the cryptographic module from electrical attack.

25. The method of claim 24 wherein said step of translating the user defined cryptographic functions into a machine-executable form includes the step of interpreting the user defined cryptographic functions.

26. The method of claim 24 wherein said memory includes erasable programmable read only memory and random access memory.

27. The method of claim 26 further comprising the step of storing at least one executable cryptographic function in said erasable programmable read only memory.

28. The method of claim 26 further comprising the step of storing at least one executable user defined cryptographic function in said random access memory.

29. The method of claim 26 wherein said random access memory is non-volatile.

30. The method of claim 24 further comprising the step of storing at least one executable cryptographic function in said memory.

31. The method of claim 24 further comprising the step of storing at least one executable user defined cryptographic function in said memory.

32. The method of claim 31 wherein said step of operating on the machine-executable form of the user defined cryptographic functions in the cryptographic module includes the step of executing code implementing at least one command for operating on the machine-executable form of the user defined cryptographic functions, wherein the at least one command is selected from the group of commands consisting of:

registering said user defined cryptographic functions in said memory,

loading said user defined cryptographic functions into said memory,

verifying that said user defined cryptographic functions have not been altered since they were registered in said memory,

deleting said user defined cryptographic functions from said memory,

invoking said user defined cryptographic functions, and

querying whether said user defined cryptographic functions have been registered in said memory.

33. The method of claim 24 wherein said step of operating on the machine-executable form of the user defined cryptographic functions in the cryptographic module includes the step of executing code implementing at least one command for operating on the machine-executable form of the user defined cryptographic functions, wherein the at least one command is selected from the group of commands consisting of:

registering said user defined cryptographic functions in said memory,

loading said user defined cryptographic functions into said memory,

verifying that said user defined cryptographic functions have not been altered since they were registered in said memory,

deleting said user defined cryptographic functions from said memory,

invoking said user defined cryptographic functions, and

querying whether said user defined cryptographic functions have been registered in said memory.

34. The method of claim 24 further comprising the step of executing code implementing a command for registering external objects in said memory.

35. The method of claim 34 further comprising the step of executing code implementing a command for versifying that said external objects have not been altered since they were registered in said memory.

36. The method of claim 34 further comprising the step of executing code implementing a command for deleting said external objects from said memory.

37. The method of claim 34 further comprising the step of executing code implementing a command for querying whether said external objects have been registered in said memory.

38. The method of claim 24 wherein said step of projecting the cryptographic module from physical attack includes the step of protecting the cryptographic module against mechanical intrusion, chemical intrusion, temperature modification, and radiation exposure.

39. The method of claim 24 wherein said step of protecting the cryptographic module from electrical attack includes the step of preventing access to said memory while a read is being performed from said memory and preventing access to said memory while an instruction which was not fetched from said memory is being executed.

40. The method of claim 24 further comprising the step of separating cryptographic keys which are used in said user defined cryptographic functions and cryptographic keys which are used for other purposes.

41. A cryptographic unit having electrical circuitry for storing and operating on user defined cryptographic functions, said cryptographic unit providing a physically and electrically secure environment, said user defined cryptographic functions including instructions arranged in a particular sequence to implement a desired cryptographic function, said cryptographic unit comprising:

memory for storing said user defined cryptographic functions, said memory including;

code for translating said user defined cryptographic functions into a machine-executable form, and

code implementing at least one command for operating on said machine-executable form of said user defined cryptographic functions;

a processing unit connected to said memory for executing said code for translating said user defined cryptographic functions into a machine-executable form and for executing said code implementing at least one command for operating on said machine-executable form of said user defined cryptographic functions;

a physical protection device for protecting said cryptographic module form physical attack; and

an electrical protection device for protecting said cryptographic module from electrical attack.

42. The cryptographic unit of claim 41 wherein said memory includes erasable programmable read only memory and random access memory.

43. The cryptographic unit of claim 41 wherein said processing unit includes a cipher processor and a microprocessor.