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

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