I'm Using this example found on github for passport local strategy with mongoose/mongodb.
The problem that I'm encountering is that when a user logs out, they can still access restricted information by hitting the back button on the browser. I'm kind of new to node.js but I would imagine that some kind of hook would need to be implemented to call the ensureAuthenticated function - located all the way at the very bottom of the code - before the back and forward buttons are executed. How can I prevent a user from accessing restricted information, by hitting the back button, after the user has logged out?
var express = require('express')
, passport = require('passport')
, LocalStrategy = require('passport-local').Strategy
, mongodb = require('mongodb')
, mongoose = require('mongoose')
, bcrypt = require('bcrypt')
, SALT_WORK_FACTOR = 10;
mongoose.connect('localhost', 'test');
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function callback() {
console.log('Connected to DB');
});
// User Schema
var userSchema = mongoose.Schema({
username: { type: String, required: true, unique: true },
email: { type: String, required: true, unique: true },
password: { type: String, required: true},
accessToken: { type: String } // Used for Remember Me
});
// Bcrypt middleware
userSchema.pre('save', function(next) {
var user = this;
if(!user.isModified('password')) return next();
bcrypt.genSalt(SALT_WORK_FACTOR, function(err, salt) {
if(err) return next(err);
bcrypt.hash(user.password, salt, function(err, hash) {
if(err) return next(err);
user.password = hash;
next();
});
});
});
// Password verification
userSchema.methods.comparePassword = function(candidatePassword, cb) {
bcrypt.compare(candidatePassword, this.password, function(err, isMatch) {
if(err) return cb(err);
cb(null, isMatch);
});
};
// Remember Me implementation helper method
userSchema.methods.generateRandomToken = function () {
var user = this,
chars = "_!abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890",
token = new Date().getTime() + '_';
for ( var x = 0; x < 16; x++ ) {
var i = Math.floor( Math.random() * 62 );
token += chars.charAt( i );
}
return token;
};
// Seed a user
var User = mongoose.model('User', userSchema);
// var usr = new User({ username: 'bob', email: 'bob@example.com', password: 'secret' });
// usr.save(function(err) {
// if(err) {
// console.log(err);
// } else {
// console.log('user: ' + usr.username + " saved.");
// }
// });
// Passport session setup.
// To support persistent login sessions, Passport needs to be able to
// serialize users into and deserialize users out of the session. Typically,
// this will be as simple as storing the user ID when serializing, and finding
// the user by ID when deserializing.
//
// Both serializer and deserializer edited for Remember Me functionality
passport.serializeUser(function(user, done) {
var createAccessToken = function () {
var token = user.generateRandomToken();
User.findOne( { accessToken: token }, function (err, existingUser) {
if (err) { return done( err ); }
if (existingUser) {
createAccessToken(); // Run the function again - the token has to be unique!
} else {
user.set('accessToken', token);
user.save( function (err) {
if (err) return done(err);
return done(null, user.get('accessToken'));
})
}
});
};
if ( user._id ) {
createAccessToken();
}
});
passport.deserializeUser(function(token, done) {
User.findOne( {accessToken: token } , function (err, user) {
done(err, user);
});
});
// Use the LocalStrategy within Passport.
// Strategies in passport require a `verify` function, which accept
// credentials (in this case, a username and password), and invoke a callback
// with a user object. In the real world, this would query a database;
// however, in this example we are using a baked-in set of users.
passport.use(new LocalStrategy(function(username, password, done) {
User.findOne({ username: username }, function(err, user) {
if (err) { return done(err); }
if (!user) { return done(null, false, { message: 'Unknown user ' + username }); }
user.comparePassword(password, function(err, isMatch) {
if (err) return done(err);
if(isMatch) {
return done(null, user);
} else {
return done(null, false, { message: 'Invalid password' });
}
});
});
}));
var app = express();
// configure Express
app.configure(function() {
app.set('views', __dirname + '/views');
app.set('view engine', 'ejs');
app.engine('ejs', require('ejs-locals'));
app.use(express.logger());
app.use(express.cookieParser());
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(express.session({ secret: 'keyboard cat' })); // CHANGE THIS SECRET!
// Remember Me middleware
app.use( function (req, res, next) {
if ( req.method == 'POST' && req.url == '/login' ) {
if ( req.body.rememberme ) {
req.session.cookie.maxAge = 2592000000; // 30*24*60*60*1000 Rememeber 'me' for 30 days
} else {
req.session.cookie.expires = false;
}
}
next();
});
// Initialize Passport! Also use passport.session() middleware, to support
// persistent login sessions (recommended).
app.use(passport.initialize());
app.use(passport.session());
app.use(app.router);
app.use(express.static(__dirname + '/../../public'));
});
app.get('/users', function(req, res) {
var users = User.find();
console.log(users);
res.send(users);
});
app.get('/', function(req, res){
res.render('index', { user: req.user });
});
app.get('/account', ensureAuthenticated, function(req, res){
res.render('account', { user: req.user });
});
app.get('/login', function(req, res){
res.render('login', { user: req.user, message: req.session.messages });
});
// POST /login
// Use passport.authenticate() as route middleware to authenticate the
// request. If authentication fails, the user will be redirected back to the
// login page. Otherwise, the primary route function function will be called,
// which, in this example, will redirect the user to the home page.
//
// curl -v -d "username=bob&password=secret" http://127.0.0.1:3000/login
//
/***** This version has a problem with flash messages
app.post('/login',
passport.authenticate('local', { failureRedirect: '/login', failureFlash: true }),
function(req, res) {
res.redirect('/');
});
*/
// POST /login
// This is an alternative implementation that uses a custom callback to
// acheive the same functionality.
app.post('/login', function(req, res, next) {
passport.authenticate('local', function(err, user, info) {
if (err) { return next(err) }
if (!user) {
req.session.messages = [info.message];
return res.redirect('/login')
}
req.logIn(user, function(err) {
if (err) { return next(err); }
return res.redirect('/');
});
})(req, res, next);
});
app.get('/logout', function(req, res){
req.logout();
res.redirect('/');
});
app.listen(3000, function() {
console.log('Express server listening on port 3000');
});
// Simple route middleware to ensure user is authenticated.
// Use this route middleware on any resource that needs to be protected. If
// the request is authenticated (typically via a persistent login session),
// the request will proceed. Otherwise, the user will be redirected to the
// login page.
function ensureAuthenticated(req, res, next) {
if (req.isAuthenticated()) { return next(); }
res.redirect('/login')
}
Edit
I think I might be on to something but can't get it to work. After doing some more research,
It seems that what I need to do is prevent local cacheing. I'm attempting to do this from within my app.configure function:
app.configure(function() {
app.use(function(req, res, next) {
res.header('Cache-Control', 'no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0');
next();
});
});
However, this does not seem to be effecting my headers.
