FastCFI: Real-Time Control Flow Integrity Using FPGA Without Code Instrumentation

Abstract

Control Flow Integrity (CFI) is an effective defense technique against a variety of memory-based cyber attacks. CFI is usually enforced through software methods, which entail considerable performance overhead. Hardware-based CFI techniques can largely avoid performance overhead, but typically rely on code instrumentation, which forms a non-trivial hurdle to the application of CFI. We develop FastCFI, an FPGA based CFI system that can perform fine-grained and stateful checking without code instrumentation. We also propose an automated Verilog generation technique that facilitates fast deployment of FastCFI. Experiments on popular benchmarks confirm that FastCFI can detect fine-grained CFI violations over unmodified binaries. The measurement results show an average of 0.36% performance overhead on SPEC 2006 benchmarks.