Free WebRTC project

Welcome! Goal of this project is to rethink approach to implementation of communication protocols in C++. Many other implementations of WebRTC stack exist in this world but this implementation is different:

• It does not have any strict dependencies (for example openssl is only one option that can be used for crypto functions)
• It is written in software architecture-agnostic way:
  • If you need just STUN message parser it is standalone
  • If you need STUN client implementation - you can get it and put it in your environment by implenting sleeps / sends etc
  • If you want secure random for STUN transaction identifiers you can replace it
  • etc.
• Code highly relies on strong typing
• Thorough unit testing (175 tests and counting)
• No quirky practicies with raw pointers and type casts.
• Test coverage
• Address sanitizer
• -Wall -Werror -pedantic from the beginning
• No global variables and side effects
• References to standards everywhere where these standards implemented

Maturity

Project is on very early stages in terms of completeness of WebRTC implementation. But pieces that are already built should be very high level of quality.

What is implemented:

• RFC 2104: HMAC: Keyed-Hashing for Message Authentication
• RFC 8489: Session Traversal Utilities for NAT (STUN)
  • Conformant STUN message parser
  • FINGERPRINT mechanism
  • Authentication with short-term credential mechanism
  • ALTERNATE-SERVER mechanism
  • Backward compatibility with RFC3489
  • All STUN attributes
  • STUN statless server
  • STUN UDP client with full transaction support
  • Initial RTO adjustment using Karn's algorithm and RFC6298
• RFC 5769: Test Vectors for Session Traversal Utilities for NAT (STUN)
• RFC 8445: Interactive Connectivity Establishment (ICE)
  • STUN Extensions (PRIORITY, ICE-CONTROLLED, ICE-CONTROLLING, USE-CANDIDATE)

Build

Known environment that can compile this code:

• Ubuntu 22.04 with gcc/g++ compiler
• macOS 12.4 with clang/clang++ compiler

To build static library and tests:

cd freewebrtc
cmake -S . -B _build
make -C _build

Run tests

_build/tests/freewebrtc_tests

Node.js examples

STUN UDP client

And example of STUN client using node.js.

Prerequisite: build freewebrtc (see above)

cd freewebrtc/examples/stun_client
npm run build
node ./index.js

Echo server

As an example and to make development closer to real-life node.js example is implemented. This is very early stage example of echo server that in future will

• Negotiate ICE connectivity
• Establish DTLS
• Receive RTP streams and return it back to client

Build and run of the example:

Client:

cd freewebrtc/examples/echo/frontend
npm install
npm run start

Server:

cd freewebrtc/examples/echo/backend
npm install
npm run build

After running server you can connect to localhost:8000 and this will be test. And don't expect too much from it. It is in the early stage.