SoK: Trusted Execution in SoC-FPGAs

Trusted Execution Environments (TEEs) have emerged at the forefront of edge computing to combat the lack of trust between system components. Field Programmable Gate Arrays (FPGAs) are commonly used as edge computers but were not created with security as a primary consideration. Thus, FPGA-based edge computers are increasingly the target of cyberattacks. We analyze the existing literature to systematize the applications and features of FPGA-based TEEs. We identified 27 primary studies related to different types of System-on-Chip FPGA-based TEEs. Across a wide range of applications and features, the availability of extensible solutions is limited. Most solutions focus on specific features and applications, whereas few solutions focus on feature-rich, comprehensive TEEs that can be utilized across computer systems. Whether TEEs are specific or extensible, the paucity of published studies provides evidence of research gaps. This SoK delineates these gaps revealing opportunities for researchers and developers.