* @category Text */ /** * * Require PEAR class for error handling. * */ require_once 'PEAR.php'; /** * * Require Text_Password class for generating the phrase. * */ require_once 'Text/Password.php'; /** * Text_CAPTCHA - creates a CAPTCHA for Turing tests * * Class to create a Turing test for websites by * creating an image, ASCII art or something else * with some (obfuscated) characters * * @package Text_CAPTCHA */ /* // This is a simple example script 0 && strlen($_SESSION['phrase']) > 0 && $_POST['phrase'] == $_SESSION['phrase']) { $msg = 'OK!'; $ok = true; unset($_SESSION['phrase']); } else { $msg = 'Please try again!'; } unlink(md5(session_id()) . '.png'); } print "
$msg
"; if (!$ok) { require_once 'Text/CAPTCHA.php'; // Set CAPTCHA image options (font must exist!) $imageOptions = array( 'font_size' => 24, 'font_path' => './', 'font_file' => 'COUR.TTF', 'text_color' => '#DDFF99', 'lines_color' => '#CCEEDD', 'background_color' => '#555555' ); // Set CAPTCHA options $options = array( 'width' => 200, 'height' => 80, 'output' => 'png', 'imageOptions' => $imageOptions ); // Generate a new Text_CAPTCHA object, Image driver $c = Text_CAPTCHA::factory('Image'); $retval = $c->init($options); if (PEAR::isError($retval)) { printf('Error initializing CAPTCHA: %s!', $retval->getMessage()); exit; } // Get CAPTCHA secret passphrase $_SESSION['phrase'] = $c->getPhrase(); // Get CAPTCHA image (as PNG) $png = $c->getCAPTCHA(); if (PEAR::isError($png)) { printf('Error generating CAPTCHA: %s!', $png->getMessage()); exit; } file_put_contents(md5(session_id()) . '.png', $png); echo ''; } ?> */ class Text_CAPTCHA { /** * Version number * * @access private * @var string */ var $_version = '0.3.1'; /** * Phrase * * @access private * @var string */ var $_phrase; /** * Create a new Text_CAPTCHA object * * @param string $driver name of driver class to initialize * * @return mixed a newly created Text_CAPTCHA object, or a PEAR * error object on error * * @see PEAR::isError() */ function &factory($driver) { if ($driver == '') { return PEAR::raiseError('No CAPTCHA type specified ... aborting. You must call ::factory() with one parameter, the CAPTCHA type.', true); } $driver = basename($driver); include_once "Text/CAPTCHA/Driver/$driver.php"; $classname = "Text_CAPTCHA_Driver_$driver"; $obj =& new $classname; return $obj; } /** * Create random CAPTCHA phrase * * This method creates a random phrase, 8 characters long * * @access private */ function _createPhrase() { $len = 8; $this->_phrase = Text_Password::create($len); } /** * Return secret CAPTCHA phrase * * This method returns the CAPTCHA phrase * * @access public * @return phrase secret phrase */ function getPhrase() { return $this->_phrase; } /** * Sets secret CAPTCHA phrase * * This method sets the CAPTCHA phrase * (use null for a random phrase) * * @access public * @param string $phrase the (new) phrase * @void */ function setPhrase($phrase = null) { if (!empty($phrase)) { $this->_phrase = $phrase; } else { $this->_createPhrase(); } } /** * Place holder for the real init() method * used by extended classes to initialize CAPTCHA * * @access private * @return PEAR_Error */ function init() { return PEAR::raiseError('CAPTCHA type not selected', true); } /** * Place holder for the real _createCAPTCHA() method * used by extended classes to generate CAPTCHA from phrase * * @access private * @return PEAR_Error */ function _createCAPTCHA() { return PEAR::raiseError('CAPTCHA type not selected', true); } /** * Place holder for the real getCAPTCHA() method * used by extended classes to return the generated CAPTCHA * (as an image resource, as an ASCII text, ...) * * @access private * @return PEAR_Error */ function getCAPTCHA() { return PEAR::raiseError('CAPTCHA type not selected', true); } } ?>