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

   1 <?php
   2 // Own namespace
   3 namespace Org\Mxchange\CoreFramework\Filter\Verifier\Captcha;
   4
   5 // Import framework stuff
   6 use Org\Mxchange\CoreFramework\Bootstrap\FrameworkBootstrap;
   7 use Org\Mxchange\CoreFramework\Factory\Object\ObjectFactory;
   8 use Org\Mxchange\CoreFramework\Filter\BaseFilter;
   9 use Org\Mxchange\CoreFramework\Filter\Chain\FilterChainException;
  10 use Org\Mxchange\CoreFramework\Filter\Filterable;
  11 use Org\Mxchange\CoreFramework\Request\Requestable;
  12 use Org\Mxchange\CoreFramework\Response\Responseable;
  13
  14 /**
  15  * A concrete filter for validating code graphical CAPTCHAs with hashes
  16  *
  17  * @author              Roland Haeder <webmaster@shipsimu.org>
  18  * @version             0.0.0
  19  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2022 Core Developer Team
  20  * @license             GNU GPL 3.0 or any newer version
  21  * @link                http://www.shipsimu.org
  22  *
  23  * This program is free software: you can redistribute it and/or modify
  24  * it under the terms of the GNU General Public License as published by
  25  * the Free Software Foundation, either version 3 of the License, or
  26  * (at your option) any later version.
  27  *
  28  * This program is distributed in the hope that it will be useful,
  29  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  30  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  31  * GNU General Public License for more details.
  32  *
  33  * You should have received a copy of the GNU General Public License
  34  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  35  */
  36 class GraphicalCodeCaptchaVerifierFilter extends BaseFilter implements Filterable {
  37         /**
  38          * Protected constructor
  39          *
  40          * @return      void
  41          */
  42         private function __construct () {
  43                 // Call parent constructor
  44                 parent::__construct(__CLASS__);
  45         }
  46
  47         /**
  48          * Creates an instance of this filter class
  49          *
  50          * @return      $filterInstance         An instance of this filter class
  51          */
  52         public static final function createGraphicalCodeCaptchaVerifierFilter () {
  53                 // Get a new instance
  54                 $filterInstance = new GraphicalCodeCaptchaVerifierFilter();
  55
  56                 // Return the instance
  57                 return $filterInstance;
  58         }
  59
  60         /**
  61          * Executes the filter with given request and response objects
  62          *
  63          * @param       $requestInstance        An instance of a class with an Requestable interface
  64          * @param       $responseInstance       An instance of a class with an Responseable interface
  65          * @return      void
  66          * @throws      FilterChainException    If this filter fails to operate
  67          */
  68         public function execute (Requestable $requestInstance, Responseable $responseInstance) {
  69                 // Is the form set?
  70                 if (($requestInstance->getRequestElement('command') !== 'do_form') || (!$requestInstance->isRequestElementSet('form'))) {
  71                         // Required field not set
  72                         $requestInstance->setIsRequestValid(FALSE);
  73
  74                         // Add fatal message
  75                         $responseInstance->addFatalMessage('command_form_invalid');
  76
  77                         // Skip further processing
  78                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
  79                 }
  80
  81                 // Create config entry
  82                 $configKey = sprintf('%s_captcha_secured', $requestInstance->getRequestElement('form'));
  83
  84                 // Is the CAPTCHA enabled?
  85                 if (FrameworkBootstrap::getConfigurationInstance()->isEnabled($configKey)) {
  86                         // Not enabled, so don't check
  87                         return;
  88                 }
  89
  90                 // Get the captcha code
  91                 $captchaCode = $requestInstance->getRequestElement('c_code');
  92
  93                 // Is this set?
  94                 if (is_null($captchaCode)) {
  95                         // Not set so request is invalid
  96                         $requestInstance->setIsRequestValid(FALSE);
  97
  98                         // Add fatal message
  99                         $responseInstance->addFatalMessage('captcha_code_unset');
 100
 101                         // Skip further processing
 102                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 103                 } elseif (empty($captchaCode)) {
 104                         // Empty value so request is invalid
 105                         $requestInstance->setIsRequestValid(FALSE);
 106
 107                         // Add fatal message
 108                         $responseInstance->addFatalMessage('captcha_code_empty');
 109
 110                         // Skip further processing
 111                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 112                 }
 113
 114                 // Get the hash as well
 115                 $captchaHash = $requestInstance->getRequestElement('hash');
 116
 117                 // Is this set?
 118                 if (is_null($captchaHash)) {
 119                         // Not set so request is invalid
 120                         $requestInstance->setIsRequestValid(FALSE);
 121
 122                         // Add fatal message
 123                         $responseInstance->addFatalMessage('captcha_hash_unset');
 124
 125                         // Skip further processing
 126                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 127                 } elseif (empty($captchaHash)) {
 128                         // Empty value so request is invalid
 129                         $requestInstance->setIsRequestValid(FALSE);
 130
 131                         // Add fatal message
 132                         $responseInstance->addFatalMessage('captcha_hash_empty');
 133
 134                         // Skip further processing
 135                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 136                 }
 137
 138                 // Now, both are set hash the given one. First get a crypto instance
 139                 $cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');
 140
 141                 // Then hash the code
 142                 $hashedCode = $cryptoInstance->hashString($captchaCode, $captchaHash);
 143
 144                 // Is this CAPTCHA valid?
 145                 if ($hashedCode != $captchaHash) {
 146                         // Not the same so request is invalid
 147                         $requestInstance->setIsRequestValid(FALSE);
 148
 149                         // Add fatal message
 150                         $responseInstance->addFatalMessage('captcha_hash_mismatch');
 151
 152                         // Skip further processing
 153                         throw new FilterChainException($this, self::EXCEPTION_FILTER_CHAIN_INTERCEPTED);
 154                 }
 155         }
 156
 157 }