Prototype of a secure real-time peer-to-peer encrypted communication network. Developed in a 36-hour period at a security hackathon.

• Example
• Architecture
• Tech stack/protocols/ideas etc.
• Features
• Design

Clone repo, get the requirements to your local virtual environment:

$ git clone https://github.com/KaroliShp/encryp.io.git
$ cd encryp.io
$ pip install -r requirements.txt

Start the server at localhost:5000:

$ python encrypio/server.py

In separate terminals start two clients which will connec:

$ python encrypio/client.py klevas
$ python encrypio/client.py berzas

Then once the connection is established, just enter the other UID in one of the terminals (for example klevas in berzas terminal) and once you're connected, click enter.

Example connection screenshot:

A diagram of the architecture:

Each user has their own UID and public and private key pair.

End users (Alice and Bob) connect to the server and authenticate with it. Security is achieved by establishing a TLS connection (both server and client verification).

One of the end users (the initiator) then asks to establish a connection with the other user(s). After the contacted user(s) has accepted the incomming connection request, the server shares relevant public keys and UIDs with relevant parties. P2P connection is then established between the parties.

P2P is secured using ECDH key exchange (with key size of 384 bits). AES keys of 256 bits size are used thereafter to encrypt the communications. Forward secrecy is achieved by using unique symmetric key for each message that gets sent - this gives assurances your session keys will not be compromised even if one of the private keys is compromised.

• Python (sockets, SSL, cryptography libraries)
• Public key infrastructure (kind of)
• Cryptography (symmetric ciphers, key-agreement protocols)
• Networking (communication via TCP-based sockets)

• Online-only messaging (theoretically, the client could locally hold a limited number of messages for the other party until the other party becomes available)

• No chat history, thus messages are NEVER stored on any server (a timer is used to ensure message self-destruction in the clients)

Some neat design solutions from one of the h4x0rz (gifs)