This is a project that is technically for the Univeristy of Southampton Space Cadets (advanced programming) classes week 4, however it's politically at the best/worst possible time for this exact project: an open source, end-to-end encrypted chat program. Therefore, I will be more explicit with the licensing of this project. The project is available under the GNU GPL v3, which means you can use this for essentially whatever, so long as it's open source.
In addition, since this contains what (I hope) is high standard cryptographic code, feel free to use parts of this program to help you learn how to write your own cryptographic code. I will also make this abundantly clear:
It is very possible that your country/region prohibits or limits this sort of technology. CHECK YOUR LOCAL LAWS BEFORE USING.
Anyway, the use of this program hasn't been documented as of yet, coming soon!