1: <?php
  2: /**
  3:  * Digest authentication
  4:  *
  5:  * PHP 5
  6:  *
  7:  * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
  8:  * Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
  9:  *
 10:  * Licensed under The MIT License
 11:  * Redistributions of files must retain the above copyright notice.
 12:  *
 13:  * @copyright     Copyright 2005-2012, Cake Software Foundation, Inc. (http://cakefoundation.org)
 14:  * @link          http://cakephp.org CakePHP(tm) Project
 15:  * @package       Cake.Network.Http
 16:  * @since         CakePHP(tm) v 2.0.0
 17:  * @license       MIT License (http://www.opensource.org/licenses/mit-license.php)
 18:  */
 19: 
 20: /**
 21:  * Digest authentication
 22:  *
 23:  * @package       Cake.Network.Http
 24:  */
 25: class DigestAuthentication {
 26: 
 27: /**
 28:  * Authentication
 29:  *
 30:  * @param HttpSocket $http
 31:  * @param array $authInfo
 32:  * @return void
 33:  * @link http://www.ietf.org/rfc/rfc2617.txt
 34:  */
 35:     public static function authentication(HttpSocket $http, &$authInfo) {
 36:         if (isset($authInfo['user'], $authInfo['pass'])) {
 37:             if (!isset($authInfo['realm']) && !self::_getServerInformation($http, $authInfo)) {
 38:                 return;
 39:             }
 40:             $http->request['header']['Authorization'] = self::_generateHeader($http, $authInfo);
 41:         }
 42:     }
 43: 
 44: /**
 45:  * Retrieve information about the authentication
 46:  *
 47:  * @param HttpSocket $http
 48:  * @param array $authInfo
 49:  * @return boolean
 50:  */
 51:     protected static function _getServerInformation(HttpSocket $http, &$authInfo) {
 52:         $originalRequest = $http->request;
 53:         $http->configAuth(false);
 54:         $http->request($http->request);
 55:         $http->request = $originalRequest;
 56:         $http->configAuth('Digest', $authInfo);
 57: 
 58:         if (empty($http->response['header']['WWW-Authenticate'])) {
 59:             return false;
 60:         }
 61:         preg_match_all('@(\w+)=(?:(?:")([^"]+)"|([^\s,$]+))@', $http->response['header']['WWW-Authenticate'], $matches, PREG_SET_ORDER);
 62:         foreach ($matches as $match) {
 63:             $authInfo[$match[1]] = $match[2];
 64:         }
 65:         if (!empty($authInfo['qop']) && empty($authInfo['nc'])) {
 66:             $authInfo['nc'] = 1;
 67:         }
 68:         return true;
 69:     }
 70: 
 71: /**
 72:  * Generate the header Authorization
 73:  *
 74:  * @param HttpSocket $http
 75:  * @param array $authInfo
 76:  * @return string
 77:  */
 78:     protected static function _generateHeader(HttpSocket $http, &$authInfo) {
 79:         $a1 = md5($authInfo['user'] . ':' . $authInfo['realm'] . ':' . $authInfo['pass']);
 80:         $a2 = md5($http->request['method'] . ':' . $http->request['uri']['path']);
 81: 
 82:         if (empty($authInfo['qop'])) {
 83:             $response = md5($a1 . ':' . $authInfo['nonce'] . ':' . $a2);
 84:         } else {
 85:             $authInfo['cnonce'] = uniqid();
 86:             $nc = sprintf('%08x', $authInfo['nc']++);
 87:             $response = md5($a1 . ':' . $authInfo['nonce'] . ':' . $nc . ':' . $authInfo['cnonce'] . ':auth:' . $a2);
 88:         }
 89: 
 90:         $authHeader = 'Digest ';
 91:         $authHeader .= 'username="' . str_replace(array('\\', '"'), array('\\\\', '\\"'), $authInfo['user']) . '", ';
 92:         $authHeader .= 'realm="' . $authInfo['realm'] . '", ';
 93:         $authHeader .= 'nonce="' . $authInfo['nonce'] . '", ';
 94:         $authHeader .= 'uri="' . $http->request['uri']['path'] . '", ';
 95:         $authHeader .= 'response="' . $response . '"';
 96:         if (!empty($authInfo['opaque'])) {
 97:             $authHeader .= ', opaque="' . $authInfo['opaque'] . '"';
 98:         }
 99:         if (!empty($authInfo['qop'])) {
100:             $authHeader .= ', qop="auth", nc=' . $nc . ', cnonce="' . $authInfo['cnonce'] . '"';
101:         }
102:         return $authHeader;
103:     }
104: 
105: }
106: