Authenticate socket.io incoming connections with JWTs. This is useful if you are build a single page application and you are not using cookies as explained in this blog post: Cookies vs Tokens. Getting auth right with Angular.JS.

Installation

npm install socketio-jwt

Example usage

// set authorization for socket.io
io.sockets
  .on('connection', socketioJwt.authorize({
    secret: 'your secret or public key',
    timeout: 15000 // 15 seconds to send the authentication message
  })).on('authenticated', function(socket) {
    //this socket is authenticated, we are good to handle more events from it.
    console.log('hello! ' + socket.decoded_token.name);
  });

Note: If you are using a base64-encoded secret (e.g. your Auth0 secret key), you need to convert it to a Buffer: Buffer('your secret key', 'base64')

Client side:

var socket = io.connect('http://localhost:9000');
socket.on('connect', function () {
  socket
    .emit('authenticate', {token: jwt}) //send the jwt
    .on('authenticated', function () {
      //do other things
    })
    .on('unauthorized', function(msg) {
      console.log("unauthorized: " + JSON.stringify(msg.data));
      throw new Error(msg.data.type);
    })
});

One roundtrip

The previous approach uses a second roundtrip to send the jwt, there is a way you can authenticate on the handshake by sending the JWT as a query string, the caveat is that intermediary HTTP servers can log the url.

var io            = require("socket.io")(server);
var socketioJwt   = require("socketio-jwt");

//// With socket.io < 1.0 ////
io.set('authorization', socketioJwt.authorize({
  secret: 'your secret or public key',
  handshake: true
}));
//////////////////////////////

//// With socket.io >= 1.0 ////
io.use(socketioJwt.authorize({
  secret: 'your secret or public key',
  handshake: true
}));
///////////////////////////////

io.on('connection', function (socket) {
  // in socket.io < 1.0
  console.log('hello!', socket.handshake.decoded_token.name);

  // in socket.io 1.0
  console.log('hello! ', socket.decoded_token.name);
})

For more validation options see auth0/jsonwebtoken.

Client side:

Append the jwt token using query string:

var socket = io.connect('http://localhost:9000', {
  'query': 'token=' + your_jwt
});

Handling token expiration

Server side:

When you sign the token with an expiration time:

var token = jwt.sign(user_profile, jwt_secret, {expiresInMinutes: 60});

Your client-side code should handle it as below.

Client side:

socket.on("unauthorized", function(error) {
  if (error.data.type == "UnauthorizedError" || error.data.code == "invalid_token") {
    // redirect user to login page perhaps?
    console.log("User's token has expired");
  }
});

Handling invalid token

Token sent by client is invalid.

Server side:

No further configuration needed.

Client side:

Add a callback client-side to execute socket disconnect server-side.

socket.on("unauthorized", function(error, callback) {
  if (error.data.type == "UnauthorizedError" || error.data.code == "invalid_token") {
    // redirect user to login page perhaps or execute callback:
    callback();
    console.log("User's token has expired");
  }
});

Server side:

To disconnect socket server-side without client-side callback:

io.sockets.on('connection', socketioJwt.authorize({
  secret: 'secret goes here',
  // No client-side callback, terminate connection server-side
  callback: false
}))

Client side:

Nothing needs to be changed client-side if callback is false.

Server side:

To disconnect socket server-side while giving client-side 15 seconds to execute callback:

io.sockets.on('connection', socketioJwt.authorize({
  secret: 'secret goes here',
  // Delay server-side socket disconnect to wait for client-side callback
  callback: 15000
}))

Your client-side code should handle it as below.

Client side:

socket.on("unauthorized", function(error, callback) {
  if (error.data.type == "UnauthorizedError" || error.data.code == "invalid_token") {
    // redirect user to login page perhaps or execute callback:
    callback();
    console.log("User's token has expired");
  }
});

Getting the secret dynamically

You can pass a function instead of an string when configuring secret. This function receives the request, the decoded token and a callback. This way, you are allowed to use a different secret based on the request and / or the provided token.

Server side:

var SECRETS = {
  'user1': 'secret 1',
  'user2': 'secret 2'
}

io.use(socketioJwt.authorize({
  secret: function(request, decodedToken, callback) {
    // SECRETS[decodedToken.userId] will be used a a secret or
    // public key for connection user.

    callback(null, SECRETS[decodedToken.userId]);
  },
  handshake: false
}));

Using JWKS

JWKS is a specification that allows the publication of public keys for the verification of JWTs.

To validate JWTs using JWKS, set the jwks option to the URL of the JWKS file:

io.use(socketioJwt.authorize({
  jwks: 'https://example.com/.well-known/jwks.json',
  handshake: true
}));

Contribute

You are always welcome to open an issue or provide a pull-request!

Also check out the unit tests:

npm test

Issue Reporting

If you have found a bug or if you have a feature request, please report them at this repository issues section. Please do not report security vulnerabilities on the public GitHub issue tracker. The Responsible Disclosure Program details the procedure for disclosing security issues.

Author

Dan Rumney

License

This project is licensed under the MIT license. See the LICENSE file for more info.