Discovering trustworthy devices using attestation and mutual attestation

1. A method comprising:

receiving, by a relying node in a network environment, attestation information from an attester node in the network environment as part of a unidirectional push of information from the attester node according to a unidirectional link layer communication scheme;

verifying a trustworthiness of the attester node by identifying a level of trust of the attester node from the attestation information, wherein the attestation information includes signed synchronization information previously received by the relying node and the attester node; and

controlling network service access of the attester node through the relying node in the network environment based on the level of trust of the attester node identified from the attestation information.

2. The method of claim 1 , wherein the signed synchronization information includes attested time information or one or more time-synchronization tokens.

3. The method of claim 2 , wherein:

the attested time information is embedded in a metadata element or token included in the signed synchronization information; and

the one or more time-synchronization tokens includes a signed timestamp issued by a central timestamp authority.

4. The method of claim 1 , wherein the signed synchronization information is indicative of a freshness of the attestation information.

5. The method of claim 1 , wherein the unidirectional link layer communication scheme implements 802.1× unidirectional discovery and authentication.

6. The method of claim 5 , wherein the relying node is an authenticator and the attester node is a supplicant.

7. The method of claim 6 , wherein the authenticator receives the attestation information of the supplicant as part of an Extensible Authentication Protocol (EAP)—Response Identity message for initiating authentication of the supplicant according to the unidirectional link layer communication scheme.

8. The method of claim 5 , wherein the relying node is a supplicant and the attester node is an authenticator.

9. The method of claim 8 , wherein the supplicant receives the attestation information from the authenticator as part of an EAP-Request Identity message for initiating authentication of the supplicant according to the unidirectional link layer communication scheme.

10. The method of claim 9 , wherein the supplicant is configured to provide supplicant attestation information to the authenticator as part of an EAP-Response Identity message for verifying the trustworthiness of the supplicant according to the unidirectional link layer communication scheme based on whether the authenticator is verified as trustworthy from the attestation information received from the authenticator.

11. The method of claim 10 , wherein the supplicant is configured to refrain from responding with the supplicant attestation information included as part of the EAP-Response Identity message if the authenticator is verified as untrustworthy from the attestation information received from the authenticator.

12. The method of claim 10 , wherein the supplicant is configured to respond with the supplicant attestation information included as part of the EAP-Response Identity message if the authenticator is verified as trustworthy from the attestation information received from the authenticator.

13. The method of claim 5 , wherein the attestation information is nested attestation information generated by the attester node in response to a challenge received at the attester node from the relying node and the nested attestation information is received from the attester node as part of the unidirectional push of information from the attester node according to the unidirectional link layer communication scheme.

14. The method of claim 1 , wherein:

the unidirectional link layer communication scheme implements one or more link layer unidirectional discovery protocols; and

the attestation information is included as part of one or more type-length-value (TLV) records in one or more messages received from the attester node.

15. The method of claim 1 , wherein the attestation information is generated based on verification by a verifier and clock synchronization between the verifier and the relying node.

16. A system comprising:

one or more hardware processors; and

at least one computer-readable storage medium having stored therein instructions which, when executed by the one or more processors, cause the one or more processors to perform operations comprising:

receiving, by a relying node in a network environment, attestation information from an attester node in the network environment as part of a unidirectional push of information from the attester node according to a unidirectional link layer communication scheme that implements either 802.1× unidirectional discovery and authentication or one or more link layer unidirectional discovery protocols;

verifying a trustworthiness of the attester node by identifying a level of trust of the attester node from the attestation information, wherein the attestation information includes signed synchronization information previously received by the relying node and the attester node; and controlling network service access of the attester node through the relying node in the network environment based on the level of trust of the attester node identified from the attestation information.

17. The system of claim 16 , wherein:

the signed synchronization information includes one or more of attested time information, one or more time-synchronization tokens, or a timestamp issued by a central timestamp authority; and

the signed synchronization information is indicative of a freshness of the attestation information.

18. The system of claim 16 , wherein the unidirectional link layer communication scheme implements 802.1× unidirectional discovery and authentication and the relying node is an authenticator and the attester node is a supplicant, further wherein the authenticator receives the attestation information of the supplicant as part of an Extensible Authentication Protocol (EAP)—Response Identity message for initiating authentication of the supplicant according to the unidirectional link layer communication scheme.

19. The system of claim 16 , wherein the unidirectional link layer communication scheme implements 802.1× unidirectional discovery and authentication and the relying node is a supplicant and the attester node is an authenticator, further wherein the supplicant receives the attestation information from the authenticator as part of an EAP-Request Identity message for initiating authentication of the supplicant according to the unidirectional link layer communication scheme.

20. A non-transitory computer-readable storage medium having stored therein instructions which, when executed by one or more processors, cause the one or more processors to perform operations comprising:

receiving, by a relying node in a network environment, attestation information from an attester node in the network environment as part of a unidirectional push of information from the attester node according to a unidirectional link layer communication scheme that implements either or both unidirectional device discovery and unidirectional authentication;

verifying a trustworthiness of the attester node by identifying a level of trust of the attester node from the attestation information, wherein the attestation information includes signed synchronization information previously received by the relying node and the attester node; and

controlling network service access of the attester node through the relying node in the network environment based on the level of trust of the attester node identified from the attestation information.