inc/main/classes/filter/verifier/class_GraphicalCodeCaptchaVerifierFilter.php

   1 <?php
   2 // Own namespace
   3 namespace CoreFramework\Filter\Verifier\Captcha;
   4
   5 // Import framework stuff
   6 use CoreFramework\Factory\ObjectFactory;
   7 use CoreFramework\Filter\BaseFilter;
   8 use CoreFramework\Request\Requestable;
   9 use CoreFramework\Response\Responseable;
  10
  11 /**
  12  * A concrete filter for validating code graphical CAPTCHAs with hashes
  13  *
  14  * @author              Roland Haeder <webmaster@shipsimu.org>
  15  * @version             0.0.0
  16  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2017 Core Developer Team
  17  * @license             GNU GPL 3.0 or any newer version
  18  * @link                http://www.shipsimu.org
  19  *
  20  * This program is free software: you can redistribute it and/or modify
  21  * it under the terms of the GNU General Public License as published by
  22  * the Free Software Foundation, either version 3 of the License, or
  23  * (at your option) any later version.
  24  *
  25  * This program is distributed in the hope that it will be useful,
  26  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28  * GNU General Public License for more details.
  29  *
  30  * You should have received a copy of the GNU General Public License
  31  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  32  */
  33 class GraphicalCodeCaptchaVerifierFilter extends BaseFilter implements Filterable {
  34         /**
  35          * Protected constructor
  36          *
  37          * @return      void
  38          */
  39         protected function __construct () {
  40                 // Call parent constructor
  41                 parent::__construct(__CLASS__);
  42         }
  43
  44         /**
  45          * Creates an instance of this filter class
  46          *
  47          * @return      $filterInstance         An instance of this filter class
  48          */
  49         public static final function createGraphicalCodeCaptchaVerifierFilter () {
  50                 // Get a new instance
  51                 $filterInstance = new GraphicalCodeCaptchaVerifierFilter();
  52
  53                 // Return the instance
  54                 return $filterInstance;
  55         }
  56
  57         /**
  58          * Executes the filter with given request and response objects
  59          *
  60          * @param       $requestInstance        An instance of a class with an Requestable interface
  61          * @param       $responseInstance       An instance of a class with an Responseable interface
  62          * @return      void
  63          * @throws      FilterChainException    If this filter fails to operate
  64          */
  65         public function execute (Requestable $requestInstance, Responseable $responseInstance) {
  66                 // Is the form set?
  67                 if (($requestInstance->getRequestElement('command') !== 'do_form') ||  (!$requestInstance->isRequestElementSet('form'))) {
  68                         // Required field not set
  69                         $requestInstance->requestIsValid(FALSE);
  70
  71                         // Add fatal message
  72                         $responseInstance->addFatalMessage('command_form_invalid');
  73
  74                         // Skip further processing
  75                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
  76                 } // END - if
  77
  78                 // Create config entry
  79                 $configKey = sprintf('%s_captcha_secured',
  80                         $requestInstance->getRequestElement('form')
  81                 );
  82
  83                 // Is the CAPTCHA enabled?
  84                 if ($this->getConfigInstance()->getConfigEntry($configKey) != 'Y') {
  85                         // Not enabled, so don't check
  86                         return;
  87                 } // END - if
  88
  89                 // Get the captcha code
  90                 $captchaCode = $requestInstance->getRequestElement('c_code');
  91
  92                 // Is this set?
  93                 if (is_null($captchaCode)) {
  94                         // Not set so request is invalid
  95                         $requestInstance->requestIsValid(FALSE);
  96
  97                         // Add fatal message
  98                         $responseInstance->addFatalMessage('captcha_code_unset');
  99
 100                         // Skip further processing
 101                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 102                 } elseif (empty($captchaCode)) {
 103                         // Empty value so request is invalid
 104                         $requestInstance->requestIsValid(FALSE);
 105
 106                         // Add fatal message
 107                         $responseInstance->addFatalMessage('captcha_code_empty');
 108
 109                         // Skip further processing
 110                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 111                 }
 112
 113                 // Get the hash as well
 114                 $captchaHash = $requestInstance->getRequestElement('hash');
 115
 116                 // Is this set?
 117                 if (is_null($captchaHash)) {
 118                         // Not set so request is invalid
 119                         $requestInstance->requestIsValid(FALSE);
 120
 121                         // Add fatal message
 122                         $responseInstance->addFatalMessage('captcha_hash_unset');
 123
 124                         // Skip further processing
 125                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 126                 } elseif (empty($captchaHash)) {
 127                         // Empty value so request is invalid
 128                         $requestInstance->requestIsValid(FALSE);
 129
 130                         // Add fatal message
 131                         $responseInstance->addFatalMessage('captcha_hash_empty');
 132
 133                         // Skip further processing
 134                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 135                 }
 136
 137                 // Now, both are set hash the given one. First get a crypto instance
 138                 $cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');
 139
 140                 // Then hash the code
 141                 $hashedCode = $cryptoInstance->hashString($captchaCode, $captchaHash);
 142
 143                 // Is this CAPTCHA valid?
 144                 if ($hashedCode != $captchaHash) {
 145                         // Not the same so request is invalid
 146                         $requestInstance->requestIsValid(FALSE);
 147
 148                         // Add fatal message
 149                         $responseInstance->addFatalMessage('captcha_hash_mismatch');
 150
 151                         // Skip further processing
 152                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 153                 } // END - not the same!
 154         }
 155
 156 }