BLOWFISH ENCRYPTION ALGORITHM

ABOUT

My Implementation of the 64-bit Blowfish Cryptographic block cipher

This is(never was) not meant to be used in production code, nor as a source of reference. This was purely a programming excercise. Mistakes & vulnerabilities are bound to creeep into this code. So don't use this code in professional environments.

REQUIREMENTS

My machine has GCC version 9.2.0. Although, any C compiler, with support of ISO C11 may be used to compile this code, preferably GCC version 4.9+

COMPILE AND RUN

gcc blowfish.c main.c -o ./blow -lm

./blow

HOW TO CHANGE PREDEFINED INPUTS

Inside main.c, there are two macro definitions, namely #define PLAINTEXT and #define KEY. Edit these values with your own custom plaintext and key values. Keep in mind, keysize should not be greater than 56 characters (preferable less than 55).

RESOURCES USED

1. https://morf.lv/introduction-to-data-encryption (basic feistel cipher and then Blowfish using Qt and C++)