This is a TCP chat room which supports real time instant messaging between clients using a custom messaging protocol. This can be ran on a local network or over the internet, the messaging protocol uses a secure key exchange between the server and client and fully encrypts all traffic
- Realtime instant messaging
- Encrypted communication
- GZIP compression
- Effective disconnection handling
- Client loads the conversation when it first connects
- Client loads a list of all of the other clients connected
- Client creates RSA public and private key
- Client sends RSA public key to the server
- Server creates an AES key
- Server encrypts the AES key with the client's RSA public key
- Server sends encrypted AES key to the client
- Client decrypts the AES key using its RSA private key
- This AES key is used throughout the rest of the session
The custom stream-based messaging protocol uses JSON based messages. Each message consists of a header and a body, the header contains the size of the body and a SHA256 hash of the body to ensure the data received is correct. Each packet has its own channel, this is a string in the header which describes what the packet is, for example a ChatMessage object would have the header "message" so the receiver knows that the packet body contains information for a message. Packets are GZIP compressed and AES encrypted before they are sent
Message Packet Structure:
- HEADER_DATA
- PACKET_SPLITTER (Delimiter to seperate the header data from the packet body)
- PACKET_BODY
This application uses SoftJson as a JSON parser to pack and unpack data
The GUI was programmed in the DearIMGUI library using OpenGL. Users can send messages, view messages and view a list of all of the connected clients. Each user has their own random username with 4 digits on the end
