pictcode

<?php

/**

 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)

 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 *

 * Licensed under The MIT License

 * For full copyright and license information, please see the LICENSE.txt

 * Redistributions of files must retain the above copyright notice.

 *

 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 * @link          http://cakephp.org CakePHP(tm) Project

 * @license       http://www.opensource.org/licenses/mit-license.php MIT License

 */

App::uses('BasicAuthenticate', 'Controller/Component/Auth');

/**

 * Digest Authentication adapter for AuthComponent.

 *

 * Provides Digest HTTP authentication support for AuthComponent. Unlike most AuthComponent adapters,

 * DigestAuthenticate requires a special password hash that conforms to RFC2617. You can create this

 * password using `DigestAuthenticate::password()`. If you wish to use digest authentication alongside other

 * authentication methods, its recommended that you store the digest authentication separately.

 *

 * Clients using Digest Authentication must support cookies. Since AuthComponent identifies users based

 * on Session contents, clients without support for cookies will not function properly.

 *

 * ### Using Digest auth

 *

 * In your controller's components array, add auth + the required settings.

 * ```

 *        public $components = array(

 *                'Auth' => array(

 *                        'authenticate' => array('Digest')

 *                )

 *        );

 * ```

 *

 * In your login function just call `$this->Auth->login()` without any checks for POST data. This

 * will send the authentication headers, and trigger the login dialog in the browser/client.

 *

 * ### Generating passwords compatible with Digest authentication.

 *

 * Due to the Digest authentication specification, digest auth requires a special password value. You

 * can generate this password using `DigestAuthenticate::password()`

 *

 * `$digestPass = DigestAuthenticate::password($username, env('SERVER_NAME'), $password);`

 *

 * Its recommended that you store this digest auth only password separate from password hashes used for other

 * login methods. For example `User.digest_pass` could be used for a digest password, while `User.password` would

 * store the password hash for use with other methods like Basic or Form.

 *

 * @package       Cake.Controller.Component.Auth

 * @since 2.0

 */

class DigestAuthenticate extends BasicAuthenticate {

/**

 * Settings for this object.

 *

 * - `fields` The fields to use to identify a user by.

 * - `userModel` The model name of the User, defaults to User.

 * - `userFields` Array of fields to retrieve from User model, null to retrieve all. Defaults to null.

 * - `scope` Additional conditions to use when looking up and authenticating users,

 *    i.e. `array('User.is_active' => 1).`

 * - `recursive` The value of the recursive key passed to find(). Defaults to 0.

 * - `contain` Extra models to contain and store in session.

 * - `realm` The realm authentication is for, Defaults to the servername.

 * - `nonce` A nonce used for authentication. Defaults to `uniqid()`.

 * - `qop` Defaults to auth, no other values are supported at this time.

 * - `opaque` A string that must be returned unchanged by clients.

 *    Defaults to `md5($settings['realm'])`

 *

 * @var array

 */

        public $settings = array(

                'fields' => array(

                        'username' => 'username',

                        'password' => 'password'

                ),

                'userModel' => 'User',

                'userFields' => null,

                'scope' => array(),

                'recursive' => 0,

                'contain' => null,

                'realm' => '',

                'qop' => 'auth',

                'nonce' => '',

                'opaque' => '',

                'passwordHasher' => 'Simple',

        );

/**

 * Constructor, completes configuration for digest authentication.

 *

 * @param ComponentCollection $collection The Component collection used on this request.

 * @param array $settings An array of settings.

 */

        public function __construct(ComponentCollection $collection, $settings) {

                parent::__construct($collection, $settings);

                if (empty($this->settings['nonce'])) {

                        $this->settings['nonce'] = uniqid('');

                }

                if (empty($this->settings['opaque'])) {

                        $this->settings['opaque'] = md5($this->settings['realm']);

                }

        }

/**

 * Get a user based on information in the request. Used by cookie-less auth for stateless clients.

 *

 * @param CakeRequest $request Request object.

 * @return mixed Either false or an array of user information

 */

        public function getUser(CakeRequest $request) {

                $digest = $this->_getDigest();

                if (empty($digest)) {

                        return false;

                }

                list(, $model) = pluginSplit($this->settings['userModel']);

                $user = $this->_findUser(array(

                        $model . '.' . $this->settings['fields']['username'] => $digest['username']

                ));

                if (empty($user)) {

                        return false;

                }

                $password = $user[$this->settings['fields']['password']];

                unset($user[$this->settings['fields']['password']]);

                if ($digest['response'] === $this->generateResponseHash($digest, $password)) {

                        return $user;

                }

                return false;

        }

/**

 * Gets the digest headers from the request/environment.

 *

 * @return array Array of digest information.

 */

        protected function _getDigest() {

                $digest = env('PHP_AUTH_DIGEST');

                if (empty($digest) && function_exists('apache_request_headers')) {

                        $headers = apache_request_headers();

                        if (!empty($headers['Authorization']) && substr($headers['Authorization'], 0, 7) === 'Digest ') {

                                $digest = substr($headers['Authorization'], 7);

                        }

                }

                if (empty($digest)) {

                        return false;

                }

                return $this->parseAuthData($digest);

        }

/**

 * Parse the digest authentication headers and split them up.

 *

 * @param string $digest The raw digest authentication headers.

 * @return array|null An array of digest authentication headers

 */

        public function parseAuthData($digest) {

                if (substr($digest, 0, 7) === 'Digest ') {

                        $digest = substr($digest, 7);

                }

                $keys = $match = array();

                $req = array('nonce' => 1, 'nc' => 1, 'cnonce' => 1, 'qop' => 1, 'username' => 1, 'uri' => 1, 'response' => 1);

                preg_match_all('/(\w+)=([\'"]?)([a-zA-Z0-9\:\#\%\?\&@=\.\/_-]+)\2/', $digest, $match, PREG_SET_ORDER);

                foreach ($match as $i) {

                        $keys[$i[1]] = $i[3];

                        unset($req[$i[1]]);

                }

                if (empty($req)) {

                        return $keys;

                }

                return null;

        }

/**

 * Generate the response hash for a given digest array.

 *

 * @param array $digest Digest information containing data from DigestAuthenticate::parseAuthData().

 * @param string $password The digest hash password generated with DigestAuthenticate::password()

 * @return string Response hash

 */

        public function generateResponseHash($digest, $password) {

                return md5(

                        $password .

                        ':' . $digest['nonce'] . ':' . $digest['nc'] . ':' . $digest['cnonce'] . ':' . $digest['qop'] . ':' .

                        md5(env('REQUEST_METHOD') . ':' . $digest['uri'])

                );

        }

/**

 * Creates an auth digest password hash to store

 *

 * @param string $username The username to use in the digest hash.

 * @param string $password The unhashed password to make a digest hash for.

 * @param string $realm The realm the password is for.

 * @return string the hashed password that can later be used with Digest authentication.

 */

        public static function password($username, $password, $realm) {

                return md5($username . ':' . $realm . ':' . $password);

        }

/**

 * Generate the login headers

 *

 * @return string Headers for logging in.

 */

        public function loginHeaders() {

                $options = array(

                        'realm' => $this->settings['realm'],

                        'qop' => $this->settings['qop'],

                        'nonce' => $this->settings['nonce'],

                        'opaque' => $this->settings['opaque']

                );

                $opts = array();

                foreach ($options as $k => $v) {

                        $opts[] = sprintf('%s="%s"', $k, $v);

                }

                return 'WWW-Authenticate: Digest ' . implode(',', $opts);

        }

}