Building Your Own Trusted Execution Environments Using FPGA
Md Armanuzzaman, Ahmad‐Reza Sadeghi, Ziming Zhao · 2024
Despite of their benefits, existing Trusted Execution Environments (TEE) or enclaves have been criticized for lack of transparency, vulnerabilities, and various restrictions. A significant limitation is that they only provide a static and fixed hardware Trusted Computing Base (TCB) that cannot be customized for different applications. The design violates the principle of least privilege by including unnecessary peripherals in the hardware TCB and buggy peripheral drivers in the software TCB. Additionally, Existing TEEs time-share a processor core with the Rich Execution Environment (REE), making execution less efficient and vulnerable to cache side-channel attacks. Although many previous projects have focused on addressing software issues in TEEs on SGX, TrustZone, or RISC-V, some TEE issues are inherent in the hardware system's design, making them impossible to resolve with software alone.