Testing the Resilience of Cryptographic Modules Against Fine-Grained Time- and Frequency-Domain EM Side-Channel Analysis Attacks
V Iyer, Aditya Thimmaiah, Ali E. Yılmaz · 2021
The ability of various countermeasures to secure cryptographic modules implementing the Advanced Encryption Standard (AES) algorithm is experimentally evaluated using fine-grained time- and frequency-domain electromagnetic side-channel analysis (EM SCA) attacks. Because an infeasibly large number of measurements of on-chip EM emanations should be required to break the cryptographic protection of a secure cryptosystem, a novel approach is used to keep acquisition costs low while testing the system resilience to EM SCA attacks. An adaptive scan protocol is used first to rapidly isolate optimal measurement configurations on an unsecured implementation. Then, the effectiveness of these optimal configurations are evaluated in the presence of countermeasures. The methodology is used to disclose the key from unsecured and secured FPGA implementations of AES-128. The most secure countermeasures are found to be >25× more resilient against the time-domain EM SCA attack and >20× more resilient against the frequency-domain EM SCA attack.