A Structured Symmetric-Key Block Cipher

摘要

This paper presents a simple and structured symmetric-key block cipher called CHAIN which provides for variation in the block size, the key size, and the number of rounds of ciphering. This cipher performs encryption in three stages: mixing, permutation, and key-dependent substitution using the simple operations of XOR, table lookup, and substitution. The structure of CHAIN is bype- oriented, however the algorithm is designed in such a way that it can be expressed in a simple 'compact form' for efficient software or hardware implementation on platforms that support word sizes greater than 8 bits (such as on Intel's Pentium processor).