$ npm install passport-iucas

var iucas_strategy = new iucas.Strategy(function(username, done) {
    //TODO - lookup user from specified username
    return done(null, {id: username, email: '[email protected]'});
});
passport.use(iucas_strategy);

//access this to login via IU CAS
app.use('/protected', passport.authenticate('iucas', { failureRedirect: '/iucas/fail' }), function(req, res, next) {
    //user object can be accessed via req.user
    //render your protected content
});

function ensureAuth(req, res, next) {
    if(req.isAuthenticated()) {
        return next();
    } else {
        res.redirect('/login');
    }
}
app.use('/protected', ensureAuth, function(req, res) {
    res.json({user: req.user});
});