Hapi Auth with JSON Web Tokens (JWT)

The authentication scheme/plugin for Hapi.js apps using JSON Web Tokens

This node.js module (Hapi plugin) lets you use JSON Web Tokens (JWTs) for authentication in your Hapi.js web application.

If you are totally new to JWTs, we wrote an introductory post explaining
the concepts & benefits: https://github.com/dwyl/learn-json-web-tokens

If you (or anyone on your team) are unfamiliar with Hapi.js we have a
quick guide for that too: https://github.com/nelsonic/learn-hapi

Usage

We tried to make this plugin as user (developer) friendly as possible, but if anything is unclear, please submit any questions as issues on GitHub: https://github.com/dwyl/hapi-auth-jwt2/issues

Install from NPM

npm install hapi-auth-jwt2 --save

Example

This basic usage example should help you get started:

var Hapi = require('hapi');

var people = { // our "users database"
    1: {
      id: 1,
      name: 'Jen Jones'
    }
};

// bring your own validation function
var validate = function (decoded, request, callback) {

    // do your checks to see if the person is valid
    if (!people[decoded.id]) {
      return callback(null, false);
    }
    else {
      return callback(null, true);
    }
};

var server = new Hapi.Server();
server.connection({ port: 8000 });
        // include our module here ↓↓
server.register(require('hapi-auth-jwt2'), function (err) {

    if(err){
      console.log(err);
    }

    server.auth.strategy('jwt', 'jwt',
    { key: 'NeverShareYourSecret',          // Never Share your secret key
      validateFunc: validate,            // validate function defined above
      verifyOptions: { algorithms: [ 'HS256' ] } // pick a strong algorithm
    });
    
    server.auth.default('jwt');

    server.route([
      {
        method: "GET", path: "/", config: { auth: false },
        handler: function(request, reply) {
          reply({text: 'Token not required'});
        }
      },
      {
        method: 'GET', path: '/restricted', config: { auth: 'jwt' },
        handler: function(request, reply) {
          reply({text: 'You used a Token!'})
          .header("Authorization", request.headers.authorization);
        }
      }
    ]);
});

server.start(function () {
  console.log('Server running at:', server.info.uri);
});

Run the server with: node example/server.js

Now use curl to access the two routes:

No Token Required

curl -v http://localhost:8000/

Token Required

Try to access the /restricted content without supplying a Token (expect to see a 401 error):

curl -v http://localhost:8000/restricted

Now access the url using the following format: curl -H "Authorization: <TOKEN>" http://localhost:8000/restricted

A here's a valid token you can use (copy-paste this command):

curl -v -H "Authorization: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpZCI6MSwibmFtZSI6IkFudGhvbnkgVmFsaWQgVXNlciIsImlhdCI6MTQyNTQ3MzUzNX0.KA68l60mjiC8EXaC2odnjFwdIDxE__iDu5RwLdN1F2A" \
http://localhost:8000/restricted

That's it.

Write your own validateFunc with what ever checks you want to perform on the decoded token before allowing the visitor to proceed.

Documentation

• key - (required) the secret key used to check the signature of the token or a key lookup function with signature function(decoded, callback) where:
  • decoded - the decoded but unverified JWT received from client
  • callback - callback function with the signature function(err, key, extraInfo) where:
    • err - an internal error
    • key - the secret key
    • extraInfo - (optional) any additional information that you would like to use in validateFunc which can be accessed via request.plugins['hapi-auth-jwt2'].extraInfo
• validateFunc - (required) the function which is run once the Token has been decoded with signature function(decoded, request, callback) where:
  • decoded - (required) is the decoded and verified JWT received from the client in request.headers.authorization
  • request - (required) is the original request received from the client
  • callback - (required) a callback function with the signature function(err, isValid, credentials) where:
    • err - an internal error.
    • valid - true if the JWT was valid, otherwise false.
    • credentials - (optional) alternative credentials to be set instead of decoded.
• verifyOptions - (optional) settings to define how tokens are verified by jsonwebtoken library
  • ignoreExpiration - ignore expired tokens
  • audience - do not enforce token audience
  • issuer - do not require the issuer to be valid
  • algorithms - list of allowed algorithms
• urlKey - (optional) if you prefer to pass your token via url, simply add a token url parameter to your request or use a custom parameter by setting urlKey
• cookieKey - (optional) if you prefer to pass your token via a cookie, simply set the cookie token=your.jsonwebtoken.here or use a custom key by setting cookieKey

verifyOptions let you define how to Verify the Tokens (Optional)

example:

server.auth.strategy('jwt', 'jwt', true,
{ key: 'NeverShareYourSecret', // Never Share your secret key
  validateFunc: validate,      // validate function defined above
  verifyOptions: {
    ignoreExpiration: true,    // do not reject expired tokens
    algorithms: [ 'HS256' ]    // specify your secure algorithm
  }
});

Read more about this at: jsonwebtoken verify options

Specify Signing Algorithm (Optional but highly recommended)

For security reasons it is recommended that you specify the allowed algorithms used when signing the tokens:

server.auth.strategy('jwt', 'jwt', true,
{ key: 'YourSuperLongKeyHere', // Never Share your secret key
  validateFunc: validate,      // validate function defined above
  verifyOptions: { algorithms: [ 'HS256' ] }  // only allow HS256 algorithm
});

If you prefer not to use any of these verifyOptions simply do not set them when registering the plugin with your app; they are all optional.

This feature was requested in: issues/29

Authentication Modes

This plugin supports authentication modes on routes.

• required - requires Authorization header to be sent with every request

• optional - if no Authorization header is provided, request will pass with request.auth.isAuthenticated set to true and request.auth.credentials set to empty object

• try - similar to optional but invalid Authorization header will pass with request.auth.isAuthenticated set to false and failed credentials provided in request.auth.credentials

Additional notes on key lookup functions

• This option to look up a secret key was added to support "multi-tenant" environments. One use case would be companies that white label API services for their customers and cannot use a shared secret key.

• The reason why you might want to pass back extraInfo in the callback is because you likely need to do a database call to get the key which also probably returns useful user data. This could save you another call in validateFunc.

URL (URI) Token

Several people requested the ability pass in JSNOWebTokens via request URL: dwyl#19

Usage

Setup your hapi.js server as described above (no special setup for using jwt tokens in urls)

https://yoursite.co/path?token=your.jsonwebtoken.here

You will need to generage valid tokens for this to work.

var JWT   = require('jsonwebtoken');
var obj   = { id:123,"name":"Charlie" }; // object/info you want to sign
var token = JWT.sign(obj, secret);
var url   = "/path?token="+token;

Generating Your Secret Key

@skota asked "How to generate secret key?" in: dwyl#48

There are several options for generating secret keys. The easist way is to simply copy paste a strong random string of alpha-numeric characters from https://www.grc.com/passwords.htm (if you want a longer key simply refresh the page and copy-paste multiple random strings)

Want to send/store your JWT in a Cookie?

@benjaminlees requested the ability to send tokens as cookies: dwyl#55
So we added the ability to optionally send/store your tokens in cookies to simplify building your web app.

To enable cookie support in your application all you need to do is add a few lines to your code:

Cookie Options

Firstly set the options you want to apply to your cookie:

var cookie_options = {
  ttl: 365 * 24 * 60 * 60 * 1000, // expires a year from today
  encoding: 'none',    // we already used JWT to encode
  isSecure: true,      // warm & fuzzy feelings
  isHttpOnly: true,    // prevent client alteration
  clearInvalid: false, // remove invalid cookies
  strictHeader: true   // don't allow violations of RFC 6265
}

Set the Cookie on your reply

Then, in your authorisation handler

reply({text: 'You have been authenticated!'})
.header("Authorization", token)        // where token is the JWT
.state("token", token, cookie_options) // set the cookie with options

For a detailed example please see: https://github.com/nelsonic/hapi-auth-jwt2-cookie-example

Background Reading

• Wikipedia has a good intro (general): https://en.wikipedia.org/wiki/HTTP_cookie
• Cookies Explained (by Nicholas C. Zakas - JavaScript über-master) http://www.nczonline.net/blog/2009/05/05/http-cookies-explained/
• The Unofficial Cookie FAQ: http://www.cookiecentral.com/faq/
• HTTP State Management Mechanism (long but complete spec): http://tools.ietf.org/html/rfc6265

---

Frequently Asked Questions (FAQ)

1. Do I need to include jsonwebtoken in my project? asked in hapi-auth-jwt2/issues/32
   Q: Must I include the jsonwebtoken package in my project [given that hapi-auth-jwt2 plugin already includes it] ?
   A: Yes, you need to manually install the jsonwebtoken node module from NPM with npm install jsonwebtoken --save if you want to sign JWTs in your app.
   Even though hapi-auth-jwt2 includes it as a dependency your app does not know where to find it in the node_modules tree for your project.
   Unless you include it via relative path e.g: var JWT = require('./node_modules/hapi-auth-jwt2/node_modules/jsonwebtoken');
   we recommend including it in your package.json explicitly as a dependency for your project.

If you have a question, please post an issue/question on GitHub: https://github.com/dwyl/hapi-auth-jwt2/issues

Real World Example ?

If you would like to see a "real world example" of this plugin in use in a production web app (API) please see: https://github.com/dwyl/time/tree/master/api/lib

• app.js registering the hapi-auth-jwt2 plugin: app.js#L13
• telling app.js where to find our validateFunction: app.js#L21
• validateFunction (how we check the JWT is still valid): api/lib/auth_jwt_validate.js looks up the person's session in our ElasticSearch Database if the session record is found (valid) and not ended we allow the person to see the restricted content.
• Signing your JWTs: in your app you need a method to sign the JWTs (and put them in a database if that's how you are verifying your sessions) ours is: api/lib/auth_jwt_sign.js

If you have any questions on this please post an issue/question on GitHub: https://github.com/dwyl/hapi-auth-jwt2/issues
(we are here to help get you started on your journey to hapiness!)

Production-ready Example using Redis?

Redis is perfect for storing session data that needs to be checked on every authenticated request.

If you are unfamiliar with Redis or anyone on your team needs a refresher, please checkout: https://github.com/dwyl/learn-redis

The code is at: https://github.com/dwyl/hapi-auth-jwt2-example and with tests. please ask additional questions if unclear!

Having a more real-world example was seconded by @manonthemat see: hapi-auth-jwt2/issues/9

---

Contributing

If you spot an area for improvement, please raise an issue: https://github.com/dwyl/hapi-auth-jwt2/issues
Someone in the dwyl team is always online so we will usually answer within a few hours.

Running the tests requires environment variables

The "real world example" expects to have two environment variables: JWT_SECRET and REDISCLOUD_URL.

Ask @nelsonic for a valid Redis Cloud url (...we cannot publish the real one on GitHub...)

export JWT_SECRET='ItsNoSecretBecauseYouToldEverybody'
export REDISCLOUD_URL='redis://rediscloud:[email protected]:10689'

tl;dr

Motivation

While making Time we want to ensure our app (and API) is as simple as possible to use.
This lead us to using JSON Web Tokens for Stateless Authentication.

We did a extensive research into existing modules that might solve our problem; there are many on NPM:

but they were invariably too complicated, poorly documented and had useless (non-real-world) "examples"!

Also, none of the existing modules exposed the request object to the validateFunc which we thought might be handy.

So we decided to write our own module addressing all these issues.

Don't take our word for it, do your own homework and decide which module you prefer.

Guiding Principal

"perfection is attained not when there is nothing more to add,
but when there is nothing more to remove" ~ Antoine de Saint-Exupéry

Why hapi-auth-jwt2 ?

The name we wanted was taken.
Think of our module as the "new, simplified and actively maintained version"

Useful Links

• For more background on jsonwebtokens (JWTs) see our detailed overview: https://github.com/dwyl/learn-json-web-tokens
• Securing Hapi Client Side Sessions: https://blog.liftsecurity.io/2014/11/26/securing-hapi-client-side-sessions

Hapi.js Auth

We borrowed code from the following:

• http://hapijs.com/tutorials/auth
• https://github.com/hapijs/hapi-auth-basic
• https://github.com/hapijs/hapi-auth-cookie
• https://github.com/hapijs/hapi-auth-hawk
• https://github.com/ryanfitz/hapi-auth-jwt (Ryan made a good start - however, when we tried to submit a pull request to improve (security) it was ignored for weeks ... an authentication plugin that ignores security updates in dependencies is a no-go for us; security matters!) If you spot any issue in hapi-auth-jwt2 please create an issue: https://github.com/dwyl/hapi-auth-jwt2/issues so we can get it resolved ASAP!