Emulating Side Channel Attacks on gem5: lessons learned

Side channel attacks (SCA) have the potential of disrupting the trust of the users on computing platforms and cryptographic algorithms. The main challenge in the design of countermeasures against such threats is that an evaluation of their effectiveness can only be performed after they have been implemented. By that point, significant resources would have been invested in the creation of a prototype. Moreover, the large volume of combinations from all the potential target algorithms and computing systems complicates a systematical analysis. It is necessary to find strategies to simplify and systematize the study of SCAs and their countermeasures. gem5 is a cycle-accurate simulator which offers the possibility to emulate a broad range of computing architectures. Beyond the functional verification, this tool computes multiple physical statistics from the simulated system. In this paper, we discuss the lessons learned from using gem5 to simulate SCAs on an ARM system. Our work shows that while there is a correlation between the data and the reported statistics, there are significant challenges that must be addressed to improve the use of gem5 for the emulation of physical phenomena.