Formal Verification of Virtualization-Based Trusted Execution Environments
Hasini Witharana, Hansika Weerasena, Prabhat Mishra · IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems · 2024
Trusted execution environments (TEEs) provide a secure environment for computation, ensuring that the code and data inside the TEE are protected with respect to confidentiality and integrity. Virtual machine (VM)-based TEEs extend this concept by utilizing virtualization technology to create isolated execution spaces that can support a complete operating system or specific applications. As the complexity and importance of VM-based TEEs grow, ensuring their reliability and security through formal verification becomes crucial. However, these technologies often operate without formal assurances of their security properties. Our research introduces a formal framework for representing and verifying VM-based TEEs. This approach provides a rigorous foundation for defining and verifying key security attributes for safeguarding execution environments. To demonstrate the applicability of our verification framework, we conduct an analysis of real-world TEE platforms, including Intel’s trust domain extensions (TDX). This work not only emphasizes the necessity of formal verification in enhancing the security of VM-based TEEs but also provides a systematic approach for evaluating the resilience of these platforms against sophisticated adversarial models.