Specification and Formal Analysis of Attestation Mechanisms in Confidential Computing

Attestation is one of the most critical mechanisms in confidential computing (CC). This talk presents a novel approach based on the combination of Trusted Execution Environment (TEE)-agnostic attestation architecture and formal analysis enabling comprehensive and rigorous security analysis of attestation mechanisms in CC. We demonstrate the application of our approach for three prominent industrial representatives, namely Arm Confidential Compute Architecture (CCA) in architecture lead solutions, Intel Trust Domain Extensions (TDX) in vendor solutions, and Secure CONtainer Environment (SCONE) in frameworks. For each of these solutions, we provide a comprehensive specification of all phases of the attestation mechanism in confidential computing, namely provisioning, initialization, and attestation protocol. Our approach reveals design and security issues in Intel TDX and SCONE attestation.