ENCRYPTION PROCESSOR, METHOD FOR BUILDING ENCRYPTION PROCESSING ALGORITHM, ENCRYPTION PROCESSING METHOD, AND COMPUTER PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide an extended Feistel-type common key block encryption process configuration for realizing a diffusion matrix switching mechanism (DSM).

SOLUTION: In an encryption process configuration using the extended Feistel structure in which a data sequence number d is an integer not smaller than 2, a plurality of different matrixes are selectively applied in the linear conversion process of the F function unit by selecting a plurality of different matrixes which satisfy the condition that the minimum branching number in all the data sequence selected from the minimum branching number corresponding to a data sequence based on the linear conversion matrix contained in the F function inputted to each data sequence of the extended Feistel structure is a value not smaller than a predetermined value. The present invention realizes a common key block encryption having a high resistance for linear analysis and differential analysis based on the DSM.

COPYRIGHT: (C)2008,JPO&INPIT