Koa CAS Authentication

This is a CAS authentication library designed to be used with an Koa server.

It provides two middleware functions for controlling access to routes:

bounce: Redirects an unauthenticated client to the CAS login page and then back to the requested page.
block: Completely denies access to an unauthenticated client and returns a 401 response.

It also provides two route endpoint functions:

bounce_redirect: Acts just like bounce but once the client is authenticated they will be redirected to the provided returnTo query parameter.
logout: De-authenticates the client with the Koa server and then redirects them to the CAS logout page.

Installation

npm install koa2-cas

Setup

import Cas from 'koa2-cas'

const cas = new Cas({
  cas_url: 'https://my-cas-host.com/cas',
  service_url: 'https://my-service-host.com',
  cas_version: '3.0',
  renew: false,
  is_dev_mode: false,
  dev_mode_user: '',
  dev_mode_info: {},
  session_name: 'cas_user',
  session_info: 'cas_userinfo',
  destroy_session: false
})

Options

Name	Type	Description	Default
cas_url	string	The URL of the CAS server.	(required)
service_url	string	The URL of the application which is registered with the CAS server as a valid service.	(required)
cas_version	"1.0"\|"2.0\|"3.0"\|"saml1.1"	The CAS protocol version.	"3.0"
renew	boolean	If true, an unauthenticated client will be required to login to the CAS system regardless of whether a single sign-on session exists.	false
is_dev_mode	boolean	If true, no CAS authentication will be used and the session CAS variable will be set to whatever user is specified as dev_mode_user.	false
dev_mode_user	string	The CAS user to use if dev mode is active.	""
dev_mode_info	Object	The CAS user information to use if dev mode is active.	{}
session_name	string	The name of the session variable that will store the CAS user once they are authenticated.	"cas_user"
session_info	string	The name of the session variable that will store the CAS user information once they are authenticated. If set to false (or something that evaluates as false), the additional information supplied by the CAS will not be forwarded. This will not work with CAS 1.0, as it does not support additional user information.	false
destroy_session	boolean	If true, the logout function will destroy the entire session upon CAS logout. Otherwise, it will only delete the session variable storing the CAS user.	false

Usage

const Koa = require('koa')
const Router = require('koa-router')
const Session = require('koa-session')
const Cas = require('koa2-cas')

// Set up an Koa session, which is required for CASAuthentication.
app.keys = ['some secret hurr']
app.use(Session(app))

// Create a new instance of CASAuthentication.
const cas = new Cas({
  cas_url: 'https://my-cas-host.com/cas',
  service_url: 'https://my-service-host.com'
})

const router = Router()

// Unauthenticated clients will be redirected to the CAS login and then back to
// this route once authenticated.
router.get('/app', cas.bounce, ctx => {
  ctx.body = '<html><body>Hello!</body></html>'
})

// Unauthenticated clients will receive a 401 Unauthorized response instead of
// the JSON data.
router.get('/api', cas.block, ctx => {
  ctx.body = { success: true }
})

// An example of accessing the CAS user session variable. This could be used to
// retrieve your own local user records based on authenticated CAS username.
router.get('/api/user', cas.block, ctx => {
  ctx.body = {
    cas_user: ctx.session[cas.session_name]
  }
})

// Unauthenticated clients will be redirected to the CAS login and then to the
// provided "redirectTo" query parameter once authenticated.
router.get('/authenticate', cas.bounce_redirect)

// This route will de-authenticate the client with the Koa server and then
// redirect the client to the CAS logout page.
router.get('/logout', cas.logout)

app.use(router.routes())

app.listen(3000, _ => {
  console.log('listening on port 3000')
})

Donny2333/koa2-sso

Koa CAS Authentication

Installation

Setup

Options

Usage