Security Evaluation Against Electromagnetic Analysis at Design Time

Abstract

Electromagnetic analysis (EMA) can be used to compromise secret information by analysing the electric and/or magnetic fields emanating from a device. It follows differential power analysis (DPA) becoming an important side channel cryptanalysis attack on many cryptographic implementations, so that constitutes a real threat to smart card security. A systematic simulation methodology is proposed to identify and assess electromagnetic (EM) leakage characteristics of secure processors at design time. This EM simulation methodology involves current flow simulation, chip layout parasitics extraction, then data processing to simulate direct EM emissions or modulated emissions. Tests implemented on synchronous and asynchronous processors indicates that the synchronous processor has data dependent EM emission, while the asynchronous processor has data dependent timing which is visible in differential EM analysis (DEMA). In particular, DEMA of amplitude demodulated emissions reveals greater leakage compared to DEMA of direct emissions and DPA. The proposed simulation methodology can be easily employed in the framework of an integrated circuit (IC) design flow to perform a systematic EM characteristics analysis.