Vigenère cipher provider
This is a very small demonstration that shows the minimum required things for a cipher in an OpenSSL 3.0 provider module.
This provider implements an extended version of the well known Vigenère cipher, covering the whole range of byte values, not just alphabetic characters. For a description of this cipher, as well as its history, see https://en.wikipedia.org/wiki/Vigenère_cipher
It goes without saying that at this day and age, this cipher should not be used in a real situation, but the implementation can be used as a template for other cipher providers to start from. If you want to use this for real, go back to the 16th century 😉
Documentation
Detailed user documentation can be found in vigenere.md.
Building
Building this provider requires cmake and a building toolchain that it supports.
Simple configuration, for a system installation of OpenSSL 3:
cmake -S . -B _build
If you have OpenSSL 3 installed somewhere else, do the following
instead, with {path} replaced with the directory of an OpenSSL 3
installation:
cmake -DCMAKE_PREFIX_PATH={path} -S . -B _build
To build, do this:
cmake --build _build
The result is _build/vigenere.so or _build/Debug/vigenere.dll.