【摘要】 有限域上的模乘和模逆运算是椭圆曲线密码体系的两个核心运算。该文在Blakley算法的基础上提出一种radix-4快速双有限域模乘算法,该算法采用Booth编码技术将原算法的迭代次数减少一半,并利用符号估计技术简化约减操作;在扩展Euclidean求逆算法的基础上提出一种能够同时支持双有限域运算的高效模逆算法,该算法不仅避免了大整数比较操作,而且提高了算法在每次迭代过程中的移位效率。然后针对这两种算法特点设计出一种能够同时完成双有限域上模乘和模逆操作的统一硬件结构。实现结果表明:256位的模乘和模逆统一硬件电路与同类型设计相比较,在电路面积没有增加的情况下,模乘运算速度提高68%,模逆运算的速度也提高了17.4%。更多还原

【Abstract】 Modular multiplication and modular inversion algorithms are the kernel of elliptic curve cryptography. In this paper,a radix-4 dual-filed modular multiplication algorithm which is based on Blakely’s algorithm is proposed. Booth’s algorithm is used to halve the iteration number of the Blakely’s algorithm,and the sign estimation is employed to simplify the modular reduction operation. A dual-field modular inversion algorithm which is derived from extended Euclidean algorithm is presented to avoid magnitude comparison and shift efficiently. Furthermore,a unified hardware structure which can support dual-field modular multiplication and modular inversion operation is designed,and the result of the hardware implementation shows that the circuit can run 68% faster for modular multiplication and 17.4% faster for modular inversion without area increasing than others.更多还原