Employing dual-complementary flip-flops to detect EMFI attacks

Abstract

Electromagnetic Fault Injection (EMFI) is a powerful class of fault attacks that can break hardware and software security mechanisms. The main advantage of EMFI over the other fault injection methods is being able to create local faults without depackaging the target chip. Therefore, designing low-cost and efficient detection mechanisms to sense EMFI is a challenging task. In this work, we propose a low-cost, fully-digital, and cycle-accurate mechanism to detect EMFI. We also present a framework to integrate the proposed detector into any logic core. We implemented the proposed detection mechanism on an Altera Cyclone-IV FPGA and integrated it with a round-serial hardware implementation of AES-128. The area overhead of this design is 14.6% and 81.5% in the number of LUTs and registers, respectively. We also experimentally demonstrated the efficiency of the implemented design under actual EM fault injection. In our experiments, we applied 20000 EM pulses with different parameters (i.e, timing, location, pulse width, energy). In total, 7% of the applied pulses causes faults in the output of the AES. The proposed mechanism successfully detected all of the injected faults without any false alarms.