As per the README.md of the upstream source at
https://github.com/B-Con/crypto-algorithms, this source code was released
into the public domain, so make that explicit in the copyright line in the
header.
Everyone loves to names similar things the same, then there're conflicts
between different libraries. The namespace prefix used is "CRYAL_", which
is weird, and that's good, as that minimizes chance of another conflict.