Abstract: Montgomery multiplication algorithm is optimized for large-bit modular multiplication and VLSI implementation. It is combined with the R-L (Right to Left) binary method to achieve speed improvement. Special efforts are focused on the problems with long-bit modular arithmetic. A Carry-Save-Adder architecture, which is implemented by redesigned (4:2) compressors, is used in the multiplier to avoid the long carry propagation. A signal-backup strategy is used to resolve the problem of signal broadcasting. Using a multiplexer-based method, the datapath of the multiplier is reconfigurable to perform either one 1024-bit-multiplication or two 512-bit multiplications in parallel. The Chinese Remainder Theorem (CRT) increases the decryption data rate by a factor of 3.8.

Key words: RSA cryptoprocessor, Montgomery modular multiplier, modular exponentiator, public-key infrastructure (PKI), VLSI, carry-save-adder architecture, signal broadcasting, Chinese Remainder Theorem (CRT)

摘要： 介绍了采用蒙哥马利模乘法算法和指数的从右到左的二进制方法，并根据大整数模乘法运算和 VLSI 实现的要求进行改进的 RSA 处理器，在提供高速 RSA 处理能力的同时，可抵抗某些定时分析攻击和功耗分析攻击。该 RSA 处理器在其模乘法器中使用了 CSA（进位保留加法器）结构以避免长进位链，并采用一种新型（4∶2）压缩器结构以减少面积和延迟。提出了信号多重备份的方法，解决信号广播带来的大的负载和线长问题。数据通路的设计采用一种基于多选器的动态重构方法，其模乘法器可以执行一个 1024 位的模乘幂运算，也可以并行执行 2 个 512 位的模乘幂运算，从而支持基于中国剩余定理的加速策略。

关键词: RSA密码处理器, 蒙哥马利模乘法器, 模乘幂器, 公钥基础设施, 超大规模集成电路, 进位保留加法器结构, 信号广播, 中国剩余定理