Fritz Alder

KU Leuven (Bélgica)

Trusted Execution with Real-Time and Availability Guarantees for Mixed-Criticality Embedded Systems

Embedded Trusted Execution Environments (TEEs) can provide hardware-enforced isolation and attestation for software in the Internet of Things or in embedded control systems. This allows us to develop highly compartmentalised distributed control systems with strong security and testability. However, many applications in this field also have stringent safety requirements. For example, a control system in a railway or smart power grid environment needs to be dependable in the sense that it upholds safety guarantees in the presence of cyber attackers. Approaches to combine the security of TEEs with real-time and availability guarantees are currently missing.

In this talk we will present technology that extends an embedded TEE with preemptive multitasking and restricted atomicity on top of strong software isolation and software attestation. Our approach allows the hardware to enforce confidentiality and integrity protections while a decoupled small software component can enforce availability and guarantee strict deadlines of critical code. We will discuss extended hardware support that allow for preemptive interruption and restricted atomicity on top of established TEE security primitives. As we will demonstrate, our open-source processor design enables the deployment of mixed-criticality software with configurable scheduling policies, and strong security and availability guarantees on light-weight open-source TEE processors.

PhD candidate at imec-DistriNet at KU Leuven, working on improving the guarantees of TEEs and extending their applicability across the computing spectrum. His recent work includes SGX cloud deployments and real-time availability guarantees for embedded TEEs.