Identify Random Delays from Side Channel Traces with HMM
Deng Gaoming, Xie Di, Liu Xiao-qin, WU Heng-xu · International Conference on Instrumentation and Measurement, Computer, Communication and Control · 2013
Hidden Markov Model (HMM) is introduced to align side channel signals in side channel analysis attacks. We investigated the mechanism of adding random delays in a software implementation to induce variance to the position of a target operation in side channel measurement traces as resistance against side channel analysis. However, the dummy instructions in software can be identified from side channel traces. Based on the instruction frequency analysis and instruction context analysis, the HMM used for side channel analysis instructions identifying is built. A DES software with dummy instruction as random delay was implemented on AT89C52 micro controller. After the HMM instance was constructed, the Viterbi decoding algorithm was used to solve the HMM problem, the experiment result verified the efficiency of the proposed method.