System and method for tamper evident certification

• US 20080155262A1
• Filed: 12/21/2006
• Published: 06/26/2008
• Est. Priority Date: 12/21/2006
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Thibadeau, Robert Harwell, Hars, Laszlo, Beaver, Donald Rozinak
• Granted Patent: US 8,281,389 B2
• Time in Patent Office: Days
• US Class Current: 713/173
• CPC Class Codes: H04L 9/0897 involving additional devices, e.g. trusted platform module [TPM], smartcard or USB
• CPC Class Codes: H04L 9/3263 involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements network architectures or network communication protocols for supporting authentication of entities using certificates in a packet data network H04L63/0823

Abstract

A storage device has a storage medium, a set of credentials stored on the storage medium, and a controller. The controller within the storage device is coupled to the storage medium, and adapted to identify security status of the storage device. The controller is adapted to alter one or more credentials of the set of credentials responsive to the security status.

Claims

1. A storage device comprising:

a storage medium; and

a controller adapted to respond to a relying party with a credential based upon a private key and indicative of security status of the storage device.

2. The storage device of claim 1 further comprising:

a security policy on the storage medium identifying one or more state changes indicative of increased vulnerability to tampering, wherein the controller determines the increased vulnerability based on the security policy.

3. The storage device of claim 2 wherein the security policy further comprises:

procedures for managing a set of credentials indicative of security of the storage device responsive to identified state changes, wherein the controller alters a credential of the set of credentials according to the procedures.

4. The storage device of claim 3 wherein the controller alters the one or more credentials by deleting, encrypting or removing the credential to prevent formation of a full trust relationship between the storage device and another device.

5. The storage device of claim 4 wherein unaltered credentials of the set of credentials allow formation of a partial trust relationship between the storage device and another device.

6. The storage device of claim 1 wherein a security of the storage device is related to a change or possible change to one or more files stored on the storage medium of the storage device.

7. The storage device of claim 2 further comprising:

a restoration agent adapted to store one or more credentials of the set of credentials and to restore the one or more credentials to the storage device upon verification that the storage device is in a known, untampered state.

8. The storage device of claim 7 wherein the restoration agent comprises a server coupled to the storage device via a secure network connection.

9. A storage device comprising:

a storage medium;

a security policy defining procedures for managing convincing evidence indivative of security status of the storage device; and

a controller adapted to manage the convincing evidence according to the security policy.

10. The storage device of claim 9 wherein the security policy comprises:

a set of state changes associated with the storage device and files stored on the storage device corresponding to potential increased vulnerability of the storage device to tampering.

11. The storage device of claim 10 wherein the set of state changes comprises software revisions, software updates, software installation, script installation, and debug inspection enablement.

12. The storage device of claim 9 wherein the convincing evidence comprises:

credentials for establishing a trust relationship between the storage device and a second device.

13. The storage device of claim 9 and further comprising:

a restoration agent adapted to restore convincing evidence based on escrowed information when the storage device is revised or restored to a known untampered state in a trusted environment.

14. The storage device of claim 9 wherein the controller is adapted to alter at least a portion of the convincing evidence responsive to a determination of a potential increased vulnerability of the storage device.

15. The system of claim 14 wherein unaltered credentials of the set of credentials allow formation of a partial trust relationship between the storage device and another device.

16. A method for tamper evident certification of a storage device comprising:

monitoring the storage device for a state change indicative of security status of the storage device; and

altering convincing evidence if a state change is identified.

17. The method of claim 16 wherein the step of monitoring comprises:

identifying state changes or interface commands associated with possible state changes to the storage device or to files stored on the storage device.

18. The method of claim 16 wherein the state change comprise a change to one or more files on the storage device based on a revision to software code of the storage device, enablement of a debugging inspection to firmware of the storage device, or installation of new software on the storage device.

19. The method of claim 18 wherein the convincing evidence comprises a private key.

20. The method of claim 19 wherein the step of altering comprises:

deleting with the controller the private key such that the private key is unavailable for establishing a trust relationship.