This is a simple implementation of an encrypted chat. It uses end-to-end AES 128 encryption.

Keys (passwords) are never sent to the server, so the system is immune to man-in-the-middle attacks. This, however, requires that a password be transmitted via a different channel.

Cryptoch contains two main modules: a client using jquery-mobile and angularJS and a server using node.js.

Cryptoch also works perfectly on mobile.

I assume you are using a Debian VPS.

If you have node.js installed, skip this step. If you don't have node.js installed, I recommend using https://github.com/creationix/nvm to install it:

wget -qO- https://raw.githubusercontent.com/creationix/nvm/v0.31.4/install.sh | bash

Then do:

source ~/.bashrc

Then install latest node.js and use it:

nvm install node
nvm use node

Now open .bashrc file in nano:

nano ~/.bashrc

And add this line at the end of this file:

nvm use node

Then use F3 to save and Ctrl+X to leave nano. Now node.js is installed.

First of all, clone git repository (If you don't have git installed do sudo apt-get install git):

git clone https://github.com/aikei/cryptoch

Then go into the created directory:

cd cryptoch

Now install an http-server module globally:

npm install -g http-server

Launch http-server which will serve the client:

http-server app

Install dependencies:

cd server
npm install

Then launch the server:

node srv.js

If you want to use SSL, change config.js file in the following way:

• set SSL to true instead of false
• set the keyPath string to the path to your key file
• set the certPath string to the path to your cert file

SSL, however, is not requiered for security, since chat password is never tramsmitted anyway, and all text is transmitted in encrypted form. This way, you don't need to trust the server.