Abstract: Based on the analysis of 34 stream ciphers such as A5, Grain and Trivium, this paper researches the structure of the linear and nonlinear feedback shift registers and summarizes the relevant operation characteristics. The special feedback shift register instructions are proposed, through configuration, which can realize multiple feedback shift registers with various structures as well as combinations formed by them. The reconfigurable hardware prototype is fabricated. This design is flexible and efficient, which can be a core function unit of the application specific microprocessor for stream ciphers.

Key words: stream cipher, feedback shift register, special instruction

摘要： 在对A5, Grain, Trivium等34种流密码算法结构进行分析的基础上，研究算法中线性和非线性反馈移位寄存器的结构特征，总结其相应操作。构造专用的反馈移位寄存器配置指令和操作指令，通过配置可灵活实现多种结构的反馈移位寄存器及其组合，并完成相应操作。设计实现支持其执行的硬件单元，可作为专用流密码微处理器的核心功能单元。

关键词: 流密码, 反馈移位寄存器, 专用指令

CLC Number: 

• TP309