/**
* Generates the captcha values
*
* @return array
*/
protected function _generate()
{
if ($this->captcha_generated === TRUE) {
return;
}
# Choose the first number randomly between 6 and 10. This is to stop the answer being negative.
$numberOne = mt_rand(6, 9);
# Choose the second number randomly between 0 and 5.
$numberTwo = mt_rand(1, 5);
# Choose the operator randomly from the array.
$captchaOperator = $this->captcha_operator_convert[mt_rand(0, count($this->captcha_operator_convert) - 1)];
# Get the equation in textual form to show to the user.
$this->captcha_text = $numberOne . ' ' . $captchaOperator . ' ' . $numberTwo;
# Evaluate the equation and get the result.
$this->captcha_result = $numberOne - $numberTwo;
# Session-Way (only one form at a time) - must be a component then
//$this->Session->write('Captcha.result', $result);
# DB-Way (several forms possible, high security via IP-Based max limits)
// the following should be done in a component and passed to the view/helper
// $Captcha = ClassRegistry::init('Captcha');
// $Captcha->new(); $Captcha->update(); etc
# Timestamp-SessionID-Hash-Way (several forms possible, not as secure)
$this->captcha_hash = SimpleCaptcha::buildHash(array('timestamp' => time(), 'result' => $this->captcha_result), $this->options);
$this->captcha_generated = TRUE;
return;
}
/**
* Validates captcha calculation
*
* flood protection by false fields and math code
* TODO: build in floodProtection (max Trials etc)
* TODO: SESSION based one as alternative
*
* @param array $data
* @return bool
*/
protected function _validateCaptcha($data)
{
if (!isset($data['captcha'])) {
# form inputs missing? SPAM!
return $this->error('Captcha content missing');
}
$captcha_params = array('timestamp' => $data['captcha_time'], 'result' => $data['captcha']);
$hash = SimpleCaptcha::buildHash($captcha_params, $this->settings[$this->Model->alias]);
if ($data['captcha_hash'] == $hash) {
return true;
}
# wrong captcha content or session expired
return $this->error('Captcha incorrect', 'SubmittedResult = \'' . $data['captcha'] . '\'');
}