모듈라 곱셈의 충돌 입력에 기반한 부채널 공격 및 대응책

Abstract

ABSTRACT The power analysis attack is a cryptanalytic technique to retri eve an user's secret key using the side-channel power leakage occurred during the execution of cryptographic algorithm embedd ed on a physical device. Especially, many power analysis attacks have targeted on an exponentiation algorithm which is c omposed of hundreds of squarings and multiplications and adopted in public key cryptosystem such as RSA. Recently, a new correlation power attack, which is tried when two modular multiplications have a same input, is proposed in order to reco ver secret key. In this paper, after reviewing the principle of side-channel attack based on input collisions in modular multip lications, we analyze the vulnerability of some exponentiation algorithms having regularity property. Furthermore, we present an improved exponentiation countermeasure to resist against the input collision-based CPA(Correlation Power Analysis) attack an d existing side channel attacks and compare its security with other countermeasures.Keywords: Power Analysis Attack, Exponentiation Algorithm, Modular Multi plication, Input Collision-based CPA