Implementation of Hash Function using Blow-CAST-Fish Algorithm in MDC-2 Compression Function

Abstract

Hash functions are one-way mathematical algorithms and produce a fixed length output string. The most widely used in many of the cryptographic applications currently are hash functions based on block ciphers. In this system MDC-2 algorithm is used to generate a compression function with a Blow-Cast-Fish block cipher. MDC-2 generates double block length and concatenated them to have the same input block length at output. MDC-2 is an unkeyed hash function. Blow-Cast-Fish is a block cipher, combination of Blowfish and Cast algorithm. In the implementation of hash function it generally consists of preprocessing, iterative processing. The output transformation is added with these general processings to achieve the optional output. MDC-2 is used in the iterated processing and Blow-Cast-Fish is used as a part in MDC-2 compression function. The result hash value from MDC-2 is compressed in the function to yield 256 fixed block length. This is again compressed in the optional function to have 128 bit hash codes. As the result, the time analysis for computing hash value of this system is compared with other hash functions (MD5 and SHA-1).