System and method for combining user and platform authentication in negotiated channel security protocols

• US 7,574,600 B2
• Filed: 03/24/2004
• Issued: 08/11/2009
• Est. Priority Date: 03/24/2004
• Status: Expired due to Fees

• Current Assignee: Tahoe Research Limited (f/k/a Learndale Limited) (Vector Capital Corporation)
• Original Assignee: Intel Corporation
• Inventors: Smith, Ned M.
• Primary Examiner(s): Moazzami; Nasser G
• Assistant Examiner(s): Traore; Fatoumata
• Application Number:
  US10/808,973
• Publication Number:
  US 20050216736A1
• Time in Patent Office: 1,966 Days
• Field of Search: 380/255, 380/259, 380/281, 380/23, 380/25, 380/44, 713/155, 713/168, 713/169, 713/170
• US Class Current: 713/168
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/166 at the transport layer

Abstract

A security protocol for combining user and platform authentication. The security protocol includes a first handshake phase to issue attestation identity credentials, and a second handshake phase to authenticate based on the attestation identity credentials issued in the first handshake phase. The security protocol also includes a session resumption phase to resume a previous session.

Claims

1. A security protocol method comprising:

cryptographically hashing a platform configuration value from a platform configuration register (PCR) in a trusted platform module (TPM) that indicates integrity of an endpoint platform, the platform configuration value representing a configuration state of the endpoint platform that indicates an integrity of the endpoint platform to generate a cryptographic hash of the platform configuration;

generating a master secret by hashing together the cryptographic hash of the platform configuration with a pre-master secret from which the master secret is derived, and data from a stored measurement log that stores configuration state measured values for the endpoint platform;

negotiating a communication channel;

signing the generated master secret with multiple authentication facets of the endpoint, the multiple authentication facets including a user key representing a particular user and a platform key representing the particular endpoint platform to produce a master secret signed with multiple authentication keys to authenticate the endpoint;

authenticating, as part of a bidirectional handshaking protocol exchange, the negotiated communication channel with the signed master secret to establish the negotiated communication channel as a secure channel to achieve late binding of the secure channel to prevent the binding from persisting outside the secure channel, including generating a session key for the communication channel, where the session key is generated from the master secret.

2. The method of claim 1, wherein a platform private key is bound to the platform configuration using the TPM.

3. The method of claim 2, wherein the TPM comprises a processor coupled to a protected storage device.

4. The method of claim 1, wherein cryptographically hashing the platform configuration comprises cryptographically hashing the platform configuration using a secure hashing algorithm.

5. The method of claim 4, wherein the secure hashing algorithm comprises Secure Hashing Algorithm Version 1.0 (SHA-1).

6. The method of claim 1, wherein the platform configuration includes multiple identities and the platform key includes one or more platform identity keys.

7. The method of claim 1, wherein the platform configuration includes multiple identities and the platform key includes each platform configuration identity key.

8. The method of claim 1, further comprising:

exchanging an explanation of the platform configuration hashes following session key negotiations to finalize the authentication;

verifying, at both endpoints, key exchange messages, certificates and platform configuration data; and

authenticating the session if no problems arise during verification.

9. The method of claim 8, further comprising halting the authentication session if problems arise during verification.

10. The method of claim 8, further comprising enabling endpoints to exchange data, wherein each endpoint knows that the platform from the other endpoint has been authenticated using a platform identity that ties to the trusted platform module.

11. A computer readable storage medium having instructions stored thereon, which when executed by a processor, provide for simultaneously authenticating multiple facets of an endpoint by:

cryptographically hashing a platform configuration value from a platform configuration register (PCR) in a trusted platform module (TPM) that indicates integrity of an endpoint platform, the platform configuration value representing a configuration state of the endpoint platform that indicates an integrity of the endpoint platform to generate a cryptographic hash of the platform configuration;

generating a master secret by hashing together the cryptographic hash of the platform configuration with a pre-master secret from which the master secret is derived, and data from a stored measurement log that stores configuration state measured values for the endpoint platform;

negotiating a communication channel;

signing the generated master secret with multiple authentication facets of the endpoint, the multiple authentication facets including a user key representing a particular user and a platform key representing the particular endpoint platform to produce a master secret signed with multiple authentication keys to authenticate the endpoint;

authenticating, as part of a bidirectional handshaking protocol exchange, the negotiated communication channel with the signed master secret to establish the negotiated communication channel as a secure channel to achieve late binding of the secure channel to prevent the binding from persisting outside the secure channel, including generating a session key for the communication channel, where the session key is generated from the master secret.

12. The computer readable storage medium of claim 11, wherein a platform private key is bound to the platform configuration using the TPM.

13. The computer readable storage medium of claim 12, wherein the TPM comprises a processor coupled to a protected storage device.

14. The computer readable storage medium of claim 11, wherein instructions for cryptographically hashing the platform configuration comprises instructions for cryptographically hashing the platform configuration using a secure hashing algorithm.

15. The computer readable storage medium of claim 14, wherein the secure hashing algorithm comprises Secure Hashing Algorithm Version 1.0 (SHA-1).

16. The computer readable storage medium of claim 11, wherein the platform configuration includes multiple identities and the platform key includes one or more platform identity keys.

17. The computer readable storage medium of claim 11, further comprising instructions for:

exchanging an explanation of the platform configuration hashes following session key negotiations to finalize the authentication;

verifying, at both endpoints, key exchange messages, certificates and platform configuration data; and

authenticating the session if no problems arise during verification.

18. The computer readable storage medium of claim 17, further comprising instructions for halting the authentication session if problems arise during verification.

19. The computer readable storage medium of claim 17, further comprising instructions for enabling endpoints to exchange data, wherein each endpoint knows that the platform from the other endpoint has been authenticated using a platform identity that ties to the trusted platform module.