Design and Implementation of a Reconfigurable Cryptographic Coprocessor with Multiple Side-Channel Attacks Countermeasures

Abstract

Nowadays, countermeasures against side-channel attack (SCA) have become necessary in hardware security. And the need for supporting multiple crypto algorithms on a chip is increasing. We propose a reconfigurable crypto coprocessor, which not only supports multiple crypto algorithms, but also provides multiple effective SCA countermeasures of SPA, DPA and EMA, by making use of its own reconfigurable features other than using extra resources. The countermeasure methods include several global and encryption flow related countermeasures, which can also be reconfigured along with the circuit function. This coprocessor is a coarse-grained reconfigurable architecture composed of several reconfigurable modules, such as logic arithmetic, shift, modular ADD/Substrate, permutation, S-box and modular multiplication units, all of which are reconfigurable. This reconfigurable cryptographic coprocessor is integrated into a system-on chip with a 32-bit CPU and fabricated in 0.18 m CMOS process with 1.8[Formula: see text]V supply and 100 MHz maximum frequency. Experimental results show that it can successfully resist SPA and DPA with one million power traces. As for EMA, if we use full countermeasures, it can resist EMA with up to 1.2 million electromagnetic traces without revealing the right subkey. Thus, this reconfigurable coprocessor can provide a good solution for both supporting multiple algorithms and providing SCA resistance, with no frequency influence, neglectable area overhead and small power overhead.