Secure and Efficient Designs for Public Key Cryptosystems

• Main Authors: Chia-YuLu, 盧嘉昱
• Other Authors: Jar-Ferr Yang
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/32831355324391260998

博士 === 國立成功大學 === 電腦與通信工程研究所 === 100 === For portable and resource-constrained devices, we may demand cryptographic primitives to provide functionality like authentication, integrity and secrecy. These cryptographic primitives (e.g., RSA and ECC) require basic operations such as modular exponentiation or point (scalar) multiplication. In practice, if modular exponentiation and point (scalar) multiplication are not protected with specific methods, they may be vulnerable to side-channel analysis (SCA), which typically includes simple power analysis (SPA) and differential power analysis (DPA). Designing a SCA-resistant multiplication algorithm requires balancing speed and security through challenging designs. We found though many SPA-resistant scalar multiplication algorithms have been proposed, most are inefficient and not interoperable with other recoding methods. Based on the concept of asynchronous strategy, we propose an efficient method to compute modular exponentiations against SPA for DSA-like schemes. To provide better multiplication algorithm, we develop a general framework based on the side-channel atomicity techniques to protect nearly all fast recoding methods/number systems. Our framework supplies security and flexibility, and has best average performance among previous works. Moreover, we give solutions to address the effects caused by conditional branches to prevent from the SN-sequence attack and its variants. Our solutions are easily incorporated to achieve more security resilience and incur low overhead in most cases. Using the proposed techniques, a comprehensive countermeasure against numerous SCAs can be accomplished while possessing competitive efficiency.