Designing Secure Cryptographic Accelerators with Information Flow Enforcement: A Case Study on AES

Designing a secure cryptographic accelerator is challenging as vulnerabilities may arise from design decisions and implementation flaws. To provide high security assurance, we propose to design and build cryptographic accelerators with hardware-level information flow control so that the security of an implementation can be formally verified. This paper uses an AES accelerator as a case study to demonstrate how to express security requirements of a cryptographic accelerator as information flow policies for security enforcement. Our AES prototype on an FPGA shows that the proposed protection has a marginal impact on area and performance.