More Practical Power Analysis Attack on LFSR Based Stream Ciphers

摘要

Power analysis attack is a powerful cryptanalytic technique aiming to extract the secret data from a cryptographic device by collecting and analyzing power consumption traces. In this paper, we present a practical power analysis attack on Linear Feedback Shift Registers (LFSR) based stream ciphers. Based on Information Theory, the problem of the power analysis attack is converted into the problem of decoding over a 3-ary symmetric channel. By setting two thresholds, the attack algorithm can significantly eliminate the effect of noise. And therefore, the correctness of decoding is enhanced. Compared with Burman's attack, the proposed attack algorithm is much more practical since the algorithmic noise and electronic noise are taken into account. Simulation results show that when the Signal to Noise Ratio (SNR) is higher than -6.5dB, the algorithm can always be practically performed and effective.