Xoodyak is lightweight cryptography algortithm. The Algorithm of Xoodyak is simply just hashing message into message digest then do Xoodoo permutation.
SHA-256 is one of the most secure in Hash family. As you might heard that MD4, MD5, SHA-1 is not collision resistance. SHA-256 is so fast, that's why we choose SHA-256 as alternative of latest, most secure Hash Algorithm, Keccak. I think this is the easiest VHDL SHA-256 Algorithm to understand, don't worry we also made "step-by-step how to use SHA-256". If you have any questions regarding the algorithm i've made. You can email me @adeirman2705. I also made this SHA-256 is so powerful, it can hash 12.7 Million bits into 256 bit message digest in matter of minutes in Python.
Keccak is winner from NIST as a Secure Hash Algorithm (SHA-3). The Algorithm is super famous, "Sponge Construction" that consist 2 big step, absorbtion and squeeze. You can try this algorithm in Python Implementation folder. In python implementation, Keccak can hash 1.2 Million bits into 384 bits in just 40 seconds.
Xoodoo Permutation is so similar with Keccak Permuatation, we simply re-arrange bits in cube 4 x 32 x 3. Xoodoo Permutation need input from SHA-256 or SHA-384 and will permutatate and resulting 384 bits.