http://spend-a-day.at/scriptalertxssscript
You might wanna sanitize the room name and username fields.
Happy to answer any questions if some.
I need to study more about symmetric key cryptography. Any good hints from where to learn about it the best.
It shouldn't be too hard to find a JS implementation. For instance: https://github.com/mdp/gibberish-aes
http://spend-a-day.at/scriptalertxssscript
You might wanna sanitize the room name and username fields.