js-smp-peer

js-smp-peer lets you run SMP(Socialist Millionaire Problem) Protocol with other users through network connections. Check out the wiki page to know more about SMP, and also the paper to understand the protocol.

Advantages of using js-smp-peer:

• Privacy: With SMP Protocol, users can compare their secrets without leaking any information. SMP Protocol implementation can be found in js-smp.
• Connection establishment at ease: A peer-to-peer connection is established for each run of SMP Protocol. Users don't need to worry about the annoying NAT traversals and other issues. They are handled by PeerJS, which utilizes WebRTC.

Setup

Install the library with npm

npm install js-smp-peer

Components

SMPPeer

SMPPeer is the core of js-smp-peer. It can initiate SMP requests and handle the requests from others.

Peer server

A Peer server makes the peers capable of discovering each others and exchanging necessary data used to establish WebRTC connections. We use PeerServer which is supported by PeerJS. Check out PeerServer for more information.

Usage

Connect to the default peer server and run SMP with a peer

import SMPPeer from 'js-smp-peer';

async function main() {
    // Secret is a plain string.
    const secret: string = 'my-secret';
    // Peer ID is the entity of you. It's a plain string as well.
    const peerID: string = 'my-peer-id';
    // Initialize a `SMPPeer`.
    const peer = new SMPPeer(secret, peerID);
    // Or you can omit `peerID`. The peer server will choose a uuid when connected to it.
    // const peer = new SMPPeer(secret);

    // Connect to the peer server, to contact or be contacted with the other peers.
    await peer.connectToPeerServer();

    // Run SMP with the peer whose id is "another-peer".
    const anotherPeer = 'another-peer';
    const result: boolean = await peer.runSMP(anotherPeer);
    console.log(`Finished running SMP with peer ${anotherPeer}, result=${result}`);
}

main();

Default peer server

By default, SMPPeer connects to the server specified in defaultPeerServerConfig in src/config.ts. The current default peer server at peekabookpeerserver.mhchia.com:8000 is run with the following command. The command peerjs can be installed with npm install peer -g.

npx peerjs --port 8000 --key peerjs --sslkey ./certs/privkey.pem --sslcert certs/cert.pem --path /myapp --allow_discovery

Use a custom peer server

You can connect to other peer servers by specifying a config when initializing SMPPeer.

const customConfig = {
  host: 'my-server'
  port: 5566,
  path: '/myapp',
  secure: true,
};

// Connect to the custom peer server.
const peer = new SMPPeer(secret, peerID, customConfig);