arXiv subjects

Alkistis Aikaterini Sigourou

Publications and source records attributed to Alkistis Aikaterini Sigourou.

4 recordsLinked to original sources

arXiv2026

Preventing Distinguishability between Multiplication and Squaring Operations

Scalar multiplication kP is a critical operation in Elliptic Curve Cryptosystems (ECC), often targeted by Side-Channel Analysis (SCA). Despite strategies based on atomic patterns to enhance security, the binary kP algorithms remain susceptible to simple SCA due to energy consumption variations in field multipliers during passing two different or two identical operands. This vulnerability arises independent of the multiplication method used. We implemented and analysed two mitigation techniques: one involving data redirection and another focusing on bus reloading.

cs.CR↗

arXiv2026

Horizontal SCA Attacks on Binary kP Algorithms using Chevallier-Mames Atomic Blocks

Scalar multiplication kP is the operation most frequently targeted in Elliptic Curve (EC) cryptosystems. To protect against single-trace Side-Channel Analysis (SCA) attacks, the atomicity principle and various atomic block patterns have been proposed in the past. In this work we use our software and hardware implementations to demonstrate that binary right-to left and left-to-right kP algorithms, when implemented with Chevallier-Mames atomic block patterns, are still vulnerable to single-trace SCA attacks. The vulnerability remains true for the left-to-right kP algorithm with projective coordinate randomization.

cs.CR↗

arXiv2024

Revisiting Atomic Patterns for Elliptic Curve Scalar Multiplication Revealing Inherent Vulnerability to Simple SCA

Elliptic Curve Scalar Multiplication denoted as kP operation is the basic operation in all Elliptic Curve based cryptographic protocols. The atomicity principle and different atomic patterns for kP algorithms were proposed in the past as countermeasures against simple side-channel analysis. In this work, we investigated the resistance of a kP algorithm implemented in hardware using Longa's atomic patterns. We analysed its simulated power trace. We show in the example of our kP implementation for the NIST EC P-256 that the field squaring operations are distinguishable from the field multiplications even if they are performed by the same field multiplier, due to the addressing of the second multiplicand. This inherent vulnerability of atomic patterns can be successfully exploited for revealing the scalar k.

cs.CR↗

arXiv2024

Practical Investigation on the Distinguishability of Longa's Atomic Patterns

This paper investigates the distinguishability of the atomic patterns for elliptic curve point doubling and addition operations proposed by Longa. We implemented a binary elliptic curve scalar multiplication kP algorithm with Longa's atomic patterns for the NIST elliptic curve P-256 using the open-source cryptographic library FLECC in C. We measured and analysed an electromagnetic trace of a single kP execution on a microcontroller (TI Launchpad F28379 board). Due to various technical limitations, significant differences in the execution time and the shapes of the atomic blocks could not be determined. Further investigations of the side channel analysis-resistance can be performed based on this work. Last but not least, we examined and corrected Longa's atomic patterns corresponding to formulae proposed by Longa.

cs.CR↗