PathFinder: side channel protection through automatic leaky paths identification and obfuscation

Side-channel analysis (SCA) attacks show an enormous threat to cryptographic integrated circuits (ICs). To address this threat, designers try to adopt various countermeasures during the IC development process. However, many existing solutions are costly in terms of area, power and/or performance, and may require full-custom circuit design for proper implementations. In this paper, we propose a tool, namely PathFinder, to automatically identify leaky paths and protect the design, and is compatible with the commercial design flow. The tool first finds out partial logic cells that leak the most information through dynamic correlation analysis. PathFinder then exploits static security checking to construct complete leaky paths based on these cells. After leaky paths are identified, PathFinder will leverage proper hardware countermeasures, including Boolean masking and random precharge, to eliminate information leakage from these paths. The effectiveness of PathFinder is validated both through simulation and physical measurements on FPGA implementations. Results demonstrate more than 1000X improvements on side-channel resistance, with less than 6.53% penalty to the power, area and performance.