1: <?php
2: /**
3: * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
4: * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
5: *
6: * Licensed under The MIT License
7: * For full copyright and license information, please see the LICENSE.txt
8: * Redistributions of files must retain the above copyright notice.
9: *
10: * @copyright Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
11: * @link http://cakephp.org CakePHP(tm) Project
12: * @license http://www.opensource.org/licenses/mit-license.php MIT License
13: */
14:
15: App::uses('BasicAuthenticate', 'Controller/Component/Auth');
16:
17: /**
18: * Digest Authentication adapter for AuthComponent.
19: *
20: * Provides Digest HTTP authentication support for AuthComponent. Unlike most AuthComponent adapters,
21: * DigestAuthenticate requires a special password hash that conforms to RFC2617. You can create this
22: * password using `DigestAuthenticate::password()`. If you wish to use digest authentication alongside other
23: * authentication methods, its recommended that you store the digest authentication separately.
24: *
25: * Clients using Digest Authentication must support cookies. Since AuthComponent identifies users based
26: * on Session contents, clients without support for cookies will not function properly.
27: *
28: * ### Using Digest auth
29: *
30: * In your controller's components array, add auth + the required settings.
31: * ```
32: * public $components = array(
33: * 'Auth' => array(
34: * 'authenticate' => array('Digest')
35: * )
36: * );
37: * ```
38: *
39: * In your login function just call `$this->Auth->login()` without any checks for POST data. This
40: * will send the authentication headers, and trigger the login dialog in the browser/client.
41: *
42: * ### Generating passwords compatible with Digest authentication.
43: *
44: * Due to the Digest authentication specification, digest auth requires a special password value. You
45: * can generate this password using `DigestAuthenticate::password()`
46: *
47: * `$digestPass = DigestAuthenticate::password($username, env('SERVER_NAME'), $password);`
48: *
49: * Its recommended that you store this digest auth only password separate from password hashes used for other
50: * login methods. For example `User.digest_pass` could be used for a digest password, while `User.password` would
51: * store the password hash for use with other methods like Basic or Form.
52: *
53: * @package Cake.Controller.Component.Auth
54: * @since 2.0
55: */
56: class DigestAuthenticate extends BasicAuthenticate {
57:
58: /**
59: * Settings for this object.
60: *
61: * - `fields` The fields to use to identify a user by.
62: * - `userModel` The model name of the User, defaults to User.
63: * - `userFields` Array of fields to retrieve from User model, null to retrieve all. Defaults to null.
64: * - `scope` Additional conditions to use when looking up and authenticating users,
65: * i.e. `array('User.is_active' => 1).`
66: * - `recursive` The value of the recursive key passed to find(). Defaults to 0.
67: * - `contain` Extra models to contain and store in session.
68: * - `realm` The realm authentication is for, Defaults to the servername.
69: * - `nonce` A nonce used for authentication. Defaults to `uniqid()`.
70: * - `qop` Defaults to auth, no other values are supported at this time.
71: * - `opaque` A string that must be returned unchanged by clients.
72: * Defaults to `md5($settings['realm'])`
73: *
74: * @var array
75: */
76: public $settings = array(
77: 'fields' => array(
78: 'username' => 'username',
79: 'password' => 'password'
80: ),
81: 'userModel' => 'User',
82: 'userFields' => null,
83: 'scope' => array(),
84: 'recursive' => 0,
85: 'contain' => null,
86: 'realm' => '',
87: 'qop' => 'auth',
88: 'nonce' => '',
89: 'opaque' => '',
90: 'passwordHasher' => 'Simple',
91: );
92:
93: /**
94: * Constructor, completes configuration for digest authentication.
95: *
96: * @param ComponentCollection $collection The Component collection used on this request.
97: * @param array $settings An array of settings.
98: */
99: public function __construct(ComponentCollection $collection, $settings) {
100: parent::__construct($collection, $settings);
101: if (empty($this->settings['nonce'])) {
102: $this->settings['nonce'] = uniqid('');
103: }
104: if (empty($this->settings['opaque'])) {
105: $this->settings['opaque'] = md5($this->settings['realm']);
106: }
107: }
108:
109: /**
110: * Get a user based on information in the request. Used by cookie-less auth for stateless clients.
111: *
112: * @param CakeRequest $request Request object.
113: * @return mixed Either false or an array of user information
114: */
115: public function getUser(CakeRequest $request) {
116: $digest = $this->_getDigest();
117: if (empty($digest)) {
118: return false;
119: }
120:
121: list(, $model) = pluginSplit($this->settings['userModel']);
122: $user = $this->_findUser(array(
123: $model . '.' . $this->settings['fields']['username'] => $digest['username']
124: ));
125: if (empty($user)) {
126: return false;
127: }
128: $password = $user[$this->settings['fields']['password']];
129: unset($user[$this->settings['fields']['password']]);
130: if ($digest['response'] === $this->generateResponseHash($digest, $password)) {
131: return $user;
132: }
133: return false;
134: }
135:
136: /**
137: * Gets the digest headers from the request/environment.
138: *
139: * @return array Array of digest information.
140: */
141: protected function _getDigest() {
142: $digest = env('PHP_AUTH_DIGEST');
143: if (empty($digest) && function_exists('apache_request_headers')) {
144: $headers = apache_request_headers();
145: if (!empty($headers['Authorization']) && substr($headers['Authorization'], 0, 7) === 'Digest ') {
146: $digest = substr($headers['Authorization'], 7);
147: }
148: }
149: if (empty($digest)) {
150: return false;
151: }
152: return $this->parseAuthData($digest);
153: }
154:
155: /**
156: * Parse the digest authentication headers and split them up.
157: *
158: * @param string $digest The raw digest authentication headers.
159: * @return array|null An array of digest authentication headers
160: */
161: public function parseAuthData($digest) {
162: if (substr($digest, 0, 7) === 'Digest ') {
163: $digest = substr($digest, 7);
164: }
165: $keys = $match = array();
166: $req = array('nonce' => 1, 'nc' => 1, 'cnonce' => 1, 'qop' => 1, 'username' => 1, 'uri' => 1, 'response' => 1);
167: preg_match_all('/(\w+)=([\'"]?)([a-zA-Z0-9\:\#\%\?\&@=\.\/_-]+)\2/', $digest, $match, PREG_SET_ORDER);
168:
169: foreach ($match as $i) {
170: $keys[$i[1]] = $i[3];
171: unset($req[$i[1]]);
172: }
173:
174: if (empty($req)) {
175: return $keys;
176: }
177: return null;
178: }
179:
180: /**
181: * Generate the response hash for a given digest array.
182: *
183: * @param array $digest Digest information containing data from DigestAuthenticate::parseAuthData().
184: * @param string $password The digest hash password generated with DigestAuthenticate::password()
185: * @return string Response hash
186: */
187: public function generateResponseHash($digest, $password) {
188: return md5(
189: $password .
190: ':' . $digest['nonce'] . ':' . $digest['nc'] . ':' . $digest['cnonce'] . ':' . $digest['qop'] . ':' .
191: md5(env('REQUEST_METHOD') . ':' . $digest['uri'])
192: );
193: }
194:
195: /**
196: * Creates an auth digest password hash to store
197: *
198: * @param string $username The username to use in the digest hash.
199: * @param string $password The unhashed password to make a digest hash for.
200: * @param string $realm The realm the password is for.
201: * @return string the hashed password that can later be used with Digest authentication.
202: */
203: public static function password($username, $password, $realm) {
204: return md5($username . ':' . $realm . ':' . $password);
205: }
206:
207: /**
208: * Generate the login headers
209: *
210: * @return string Headers for logging in.
211: */
212: public function loginHeaders() {
213: $options = array(
214: 'realm' => $this->settings['realm'],
215: 'qop' => $this->settings['qop'],
216: 'nonce' => $this->settings['nonce'],
217: 'opaque' => $this->settings['opaque']
218: );
219: $opts = array();
220: foreach ($options as $k => $v) {
221: $opts[] = sprintf('%s="%s"', $k, $v);
222: }
223: return 'WWW-Authenticate: Digest ' . implode(',', $opts);
224: }
225:
226: }
227: