Method for extending the CRTM in a trusted platform

• US 20060010326A1
• Filed: 07/08/2004
• Published: 01/12/2006
• Est. Priority Date: 07/08/2004
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bade, Steven A., Van Doorn, Leendert Peter, Perez, Ronald, Weber, Helmut H.
• Application Number:
  US10/887,441
• Publication Number:
  US 20060010326A1
• Time in Patent Office: Days
• US Class Current: 713/176
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]

Abstract

A method, system and computer program product for enhancing the functionality of the existing core root of trust measurement (CRTM). The CRTM is extended to allow platform manufacturer controlled and certified code to be incorporated into the function of the CRTM, wherein the manufacturer may define the policy for accepting a new function into the CRTM. When a firmware or software module image is compiled, the build process generates a hash value of the compiled firmware or software image, wherein the hash value reflects a fingerprint (or short hand) representation of the compiled image. A determination is made as to whether the hash value of the firmware or software image is to be a CRTM extension. If so, a digital signature of the module is created using the CRTM extension private key. This signature value is added to the firmware or software module.

Claims

1. A method in a data processing system for extending a core root of trust measurement within a trusted computing platform, comprising:

responsive to compiling a module image, generating a hash value;

determining if the hash value of the module image is to be an extension of the core root of trust measurement;

in response to determining that the hash value of the module image is to be a core root of trust measurement extension, creating a digital signature for the module using the core root of trust measurement private key; and

adding the digital signature to the module, wherein adding the digital signature allows platform manufacturer controlled and certified code to be incorporated into functions of the core root of trust measurement.

2. The method of claim 1, further comprising:

responsive to determining that the hash value of the module image is not to be a core root of trust measurement extension, releasing the module image.

3. The method of claim 1, wherein incorporating platform manufacturer controlled and certified code into the core root of trust measurement allows the platform manufacturer to define a policy for accepting a new function into the core root of trust measurement.

4. The method of claim 3, wherein the extended core root of trust measurement may be updated using the manufacturer defined policy.

5. The method of claim 1, wherein the module is a firmware module.

6. The method of claim 1, wherein the module is a software module.

7. A method in a data processing system for allowing a core root of trust measurement within a trusted computing platform to validate a module signature against a public key of a manufacturer, comprising:

loading the module into the data processing system;

determining if the module is signed by a core root of trust measurement extension signing key;

responsive to determining that the module is signed, validating the module signature against the public key of the manufacturer; and

creating an entry in a platform configuration register, wherein the platform configuration register is extended to include functions of the core root of trust measurement.

8. A data processing system for extending a core root of trust measurement within a trusted computing platform, comprising:

generating means for generating a hash value in response to compiling a module image;

determining means for determining if the hash value of the module image is to be a core root of trust measurement extension;

creating means for creating a digital signature for the module using the core root of trust measurement private key in response to determining that the hash value of the module image is to be a core root of trust measurement extension; and

adding means for adding the digital signature to the module, wherein adding the digital signature allows platform manufacturer controlled and certified code to be incorporated into functions of the core root of trust measurement.

9. The data processing system of claim 8, further comprising:

releasing means for releasing the module image in response determining that the hash value of the module image is not to be a core root of trust measurement extension.

10. The data processing system of claim 8, wherein incorporating platform manufacturer controlled and certified code into the core root of trust measurement allows the platform manufacturer to define a policy for accepting a new function into the CRTM.

11. The data processing system of claim 10, wherein the extended core root of trust measurement may be updated using the manufacturer defined policy.

12. The data processing system of claim 8, wherein the module is a firmware module.

13. The data processing system of claim 8, wherein the module is a software module.

14. A computer program product in a computer readable medium for extending a core root of trust measurement within a trusted computing platform, comprising:

first instructions for generating a hash value in response to compiling a module image;

second instructions for determining if the hash value of the module image is to be a core root of trust measurement extension;

third instructions for creating a digital signature for the module using the core root of trust measurement private key in response to determining that the hash value of the module image is to be a core root of trust measurement extension; and

fourth instructions for adding the digital signature to the module, wherein adding the digital signature allows platform manufacturer controlled and certified code to be incorporated into functions of the core root of trust measurement.

15. The computer program product of claim 14, further comprising:

fifth instructions for releasing the module image in response to determining that the hash value of the module image is not to be a core root of trust measurement extension.

16. The computer program product of claim 14, wherein incorporating platform manufacturer controlled and certified code into the core root of trust measurement allows the platform manufacturer to define a policy for accepting a new function into the core root of trust measurement.

17. The computer program product of claim 16, wherein the extended core root of trust measurement may be updated using the manufacturer defined policy.

18. The computer program product of claim 14, wherein the module is a firmware module.

19. The computer program product of claim 14, wherein the module is a software module.