A randomised scheme for secured modular exponentiation against power analysis attacks

This paper presents an approach to compute secured modular exponentiation to mitigate power analysis attacks. Two processes have been designed based on ‘multiply-always’ binary method, which injects dummy multiplications so that the original multiplications can remain intact. The two processes are being invoked based on a random variable, which generated either 0 or 1. With these randomised modular exponentiation, the proposed approach can resist simple and differential power analysis attacks to a large extent. The proposed approach has been implemented using conventional ‘squaring-multiplication’ and ‘Montgomery-Ladder’ methods. Further, the work has also been extended to CRT-RSA, which is widely used for fast computation. The proposed method has been implemented for different key sizes of 1024-bit, 1536-bit and 2048-bit RSA & CRT-RSA. The analysis and results show that with a complexity of O(n), the proposed approach can resist some of the standard DPA attacks on modular exponentiation. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.