HeliTeknik / PHP-Auth

Authentication for PHP. Simple, lightweight and secure.

Auth

Authentication for PHP. Simple, lightweight and secure.

Written once, to be used everywhere.

Completely framework-agnostic and database-agnostic.

Why do I need this?

• There are tons of websites with weak authentication systems. Don't build such a site.
• Re-implementing a new authentication system for every PHP project is not a good idea.
• Building your own authentication classes piece by piece, and copying it to every project, is not recommended, either.
• A secure authentication system with an easy-to-use API should be thoroughly designed and planned.
• Peer-review for your critical infrastructure is a must.

Requirements

• PHP 5.5.0+
  • OpenSSL extension
• MySQL 5.5.3+ or MariaDB 5.5.23+

Installation

• Set up the PHP library

  • Install via Composer (recommended)

    $ composer require delight-im/auth

    Include the Composer autoloader:

    require __DIR__.'/vendor/autoload.php';

  • or

  • Install manually

    • Copy the contents of the src directory to a subfolder of your project
    • Include the files in your code via require or require_once
• Set up a database and create the required tables
  • MySQL

Usage

Create a new instance

// $db = new PDO('mysql:dbname=database;host=localhost;charset=utf8mb4', 'username', 'password');
// $db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$auth = new \Delight\Auth\Auth($db);

If you have an open PDO connection already, just re-use it.

If you do enforce HTTPS on your site, pass true as the second parameter to the constructor. This is optional and the default is false.

Only in the very rare case that you need access to your cookies from JavaScript, pass true as the third argument to the constructor. This is optional and the default is false. There is almost always a better solution than enabling this, however.

If your web server is behind a proxy server and $_SERVER['REMOTE_ADDR'] only contains the proxy's IP address, you must pass the user's real IP address to the constructor in the fourth argument. The default is null.

Sign up a new user (register)

try {
    $userId = $auth->register($_POST['email'], $_POST['password'], $_POST['username'], function ($selector, $token) {
        // send `$selector` and `$token` to the user (e.g. via email)
    });

    // we have signed up a new user with the ID `$userId`
}
catch (\Delight\Auth\InvalidEmailException $e) {
    // invalid email address
}
catch (\Delight\Auth\InvalidPasswordException $e) {
    // invalid password
}
catch (\Delight\Auth\UserAlreadyExistsException $e) {
    // user already exists
}
catch (\Delight\Auth\TooManyRequestsException $e) {
    // too many requests
}

The username in the third parameter is optional. You can pass null here if you don't want to manage usernames.

For email verification, you should build an URL with the selector and token and send it to the user, e.g.:

$url = 'https://www.example.com/verify_email?selector='.urlencode($selector).'&token='.urlencode($token);

If you don't want to perform email verification, just omit the last parameter to register(...). The new user will be active immediately, then.

Sign in an existing user (login)

try {
    $auth->login($_POST['email'], $_POST['password'], ($_POST['remember'] == 1));

    // user is logged in
}
catch (\Delight\Auth\InvalidEmailException $e) {
    // wrong email address
}
catch (\Delight\Auth\InvalidPasswordException $e) {
    // wrong password
}
catch (\Delight\Auth\EmailNotVerifiedException $e) {
    // email not verified
}
catch (\Delight\Auth\TooManyRequestsException $e) {
    // too many requests
}

The third parameter controls whether the login is persistent with a long-lived cookie. With such a persistent login, users may stay authenticated for a long time, even when the browser session has already been closed and the session cookies have expired. Typically, you'll want to keep the user logged in for weeks or months with this feature, which is known as "remember me" or "keep me logged in". Many users will find this more convenient, but it may be less secure if they leave their devices unattended.

Without the persistent login, which is the default behavior, a user will only stay logged in until they close their browser, or as long as configured via session.cookie_lifetime and session.gc_maxlifetime in PHP.

Set the third parameter to false to disable the feature. Otherwise, ask the user if they want to enable "remember me". This is usually done with a checkbox in your user interface. Use the input from that checkbox to decide between false and true here. This is optional and the default is false.

Perform email verification

Extract the selector and token from the URL that the user clicked on in the verification email.

try {
    $auth->confirmEmail($_GET['selector'], $_GET['token']);

    // email address has been verified
}
catch (\Delight\Auth\InvalidSelectorTokenPairException $e) {
    // invalid token
}
catch (\Delight\Auth\TokenExpiredException $e) {
    // token expired
}
catch (\Delight\Auth\TooManyRequestsException $e) {
    // too many requests
}

Change the current user's password

If a user is currently logged in, they may change their password.

try {
    $auth->changePassword($_POST['oldPassword'], $_POST['newPassword']);

    // password has been changed
}
catch (\Delight\Auth\NotLoggedInException $e) {
    // not logged in
}
catch (\Delight\Auth\InvalidPasswordException $e) {
    // invalid password(s)
}

Logout

$auth->logout();

// user has been signed out

Check if the user is signed in

if ($auth->isLoggedIn()) {
    // user is signed in
}
else {
    // user is *not* signed in yet
}

A shorthand/alias for this method is $auth->check().

Get the user's ID

$id = $auth->getUserId();

If the user is not currently signed in, this returns null.

A shorthand/alias for this method is $auth->id().

Get the user's email address

$email = $auth->getEmail();

If the user is not currently signed in, this returns null.

Get the user's display name

$email = $auth->getUsername();

Remember that usernames are optional and there is only a username if you supplied it during registration.

If the user is not currently signed in, this returns null.

Check if the user was "remembered"

if ($auth->isRemembered()) {
    // user did not sign in but was logged in through their long-lived cookie
}
else {
    // user signed in manually
}

If the user is not currently signed in, this returns null.

Get the user's IP address

$ip = $auth->getIpAddress();

Read and write session data

For detailed information on how to read and write session data conveniently, please refer to the documentation of the session library, which is included by default.

Utilities

Create a random string

$length = 24;
$randomStr = \Delight\Auth\Auth::createRandomString($length);

Create a UUID v4 as per RFC 4122

$uuid = \Delight\Auth\Auth::createUuid();

Features

• registration
  • secure password storage using the bcrypt algorithm
  • email verification through message with confirmation link
  • assurance of unique email addresses
  • customizable password requirements and enforcement
  • optional usernames with customizable restrictions
• login
  • keeping the user logged in for a long time (beyond expiration of browser session) via secure long-lived token ("remember me")
• account management
  • change password
  • tracking the time of sign up and last login
  • check if user has been logged in via "remember me" cookie
• logout
  • full and reliable destruction of session
• session management
  • protection against session hijacking via cross-site scripting (XSS)
    • do not permit script-based access to cookies
    • restrict cookies to HTTPS to prevent session hijacking via non-secure HTTP
  • protection against session fixation attacks
  • protection against cross-site request forgery (CSRF)
    • works automatically (i.e. no need for CSRF tokens everywhere)
    • do not use HTTP GET requests for "dangerous" operations
• throttling
  • per IP address
  • per account
• enhanced HTTP security
  • prevents clickjacking
  • prevent content sniffing (MIME sniffing)
  • disables caching of potentially sensitive data
• miscellaneous
  • ready for both IPv4 and IPv6
  • works behind proxy servers as well
  • privacy-friendly (e.g. does not save readable IP addresses)

Exceptions

This library throws two types of exceptions to indicate problems:

• AuthException and its subclasses are thrown whenever a method does not complete successfully. You should always catch these exceptions as they carry the normal error responses that you must react to.
• AuthError and its subclasses are thrown whenever there is an internal problem or the library has not been installed correctly. You should not catch these exceptions.

General advice

• Both serving the authentication pages (e.g. login and registration) and submitting the data entered by the user should only be done over TLS (HTTPS).
• You should enforce a minimum length for passwords, e.g. 10 characters, but no maximum length. Moreover, you should not restrict the set of allowed characters.
• Whenever a user was remembered ("remember me") and did not log in by entering their password, you should require re-authentication for critical features.
• Encourage users to use passphrases, i.e. combinations of words or even full sentences, instead of single passwords.
• Do not prevent users' password managers from working correctly. Thus please use the standard form fields only and do not prevent copy and paste.
• Before executing sensitive account operations (e.g. changing a user's email address, deleting a user's account), you should always require re-authentication, i.e. require the user to sign in once more.
• You should not offer an online password reset feature ("forgot password") for high-security applications.
• For high-security applications, you should not use email addresses as identifiers. Instead, choose identifiers that are specific to the application and secret, e.g. an internal customer number.

Contributing

All contributions are welcome! If you wish to contribute, please create an issue first so that your feature, problem or question can be discussed.

License

This project is licensed under the terms of the MIT License.