A novel SM4 cryptographic architecture against higher order power analysis attacks.

In this letter, a novel secret merchant‐4 (SM4) cryptographic circuit implementation is proposed against higher order power analysis attacks (PAAs). Four different random number generators (RNGs) are embedded into the SM4 architecture for breaking the correlation between the processed data and monitored power dissipation against PAAs. Firstly, fake keys are created by the first RNG to scramble the critical information related with the actual secret key. Furthermore, the second RNG controls the implementations of substitution boxes (Sboxes) with composite fields or look‐up tables randomly while the third RNG randomizes the substitution locations with respect to these Sboxes. Ultimately, the fourth RNG randomly swaps the behaviors of the fake SM4 and true SM4 to further break the critical correlation. Under the assistance of the four embedded RNGs, the proposed SM4 cryptographic architecture is capable of resisting against fourth‐order PAAs effectively with a 300 Mbps throughput and 165,354 μm2 area after synthesizing in the TSMC 90 nm process design kits (PDK). [ABSTRACT FROM AUTHOR]