$value )
{
$req .= $key . "=" . urlencode(stripslashes($value)) . "&";
}
$req = substr($req, 0, strlen($req) - 1);
return $req;
}
/**
* Submits an HTTP POST to a reCAPTCHA server
* @param string $host
* @param string $path
* @param array $data
* @param int port
* @return array response
*/
function _recaptcha_http_post($host, $path, $data, $port = 80)
{
$req = _recaptcha_qsencode($data);
$http_request = "POST " . $path . " HTTP/1.0\r\n";
$http_request .= "Host: " . $host . "\r" . "\n";
$http_request .= "Content-Type: application/x-www-form-urlencoded;\r\n";
$http_request .= "Content-Length: " . strlen($req) . "\r\n";
$http_request .= "User-Agent: reCAPTCHA/PHP\r\n";
$http_request .= "\r\n";
$http_request .= $req;
$response = '';
if( false == ($fs = @fsockopen($host, $port, $errno, $errstr, 10)) )
{
exit( "reCAPTCHA Error: Could not open socket" );
}
fwrite($fs, $http_request);
while( !feof($fs) )
{
$response .= fgets($fs, 1160);
}
fclose($fs);
$response = explode("\r\n\r\n", $response, 2);
return $response;
}
/**
* Gets the challenge HTML (javascript and non-javascript version).
* This is called from the browser, and the resulting reCAPTCHA HTML widget
* is embedded within the HTML form it was called from.
* @param string $pubkey A public key for reCAPTCHA
* @param string $error The error given by reCAPTCHA (optional, default is null)
* @param boolean $use_ssl Should the request be made over ssl? (optional, default is false)
* @return string - The HTML to be embedded in the user's form.
*/
function recaptcha_get_html($pubkey, $error = null, $use_ssl = false)
{
if( $pubkey == null || $pubkey == '' )
{
return "Required reCAPTCHA Keys missing from Setup > General Settings > Security";
}
if( $_SERVER['HTTPS'] && $_SERVER['HTTPS'] != 'off' )
{
$use_ssl = true;
}
if( $use_ssl )
{
$server = RECAPTCHA_API_SECURE_SERVER;
}
else
{
$server = RECAPTCHA_API_SERVER;
}
$errorpart = '';
if( $error )
{
$errorpart = "&error=" . $error;
}
return "\n ";
}
/**
* Calls an HTTP POST function to verify if the user's guess was correct
* @param string $privkey
* @param string $remoteip
* @param string $challenge
* @param string $response
* @param array $extra_params an array of extra variables to post to the server
* @return ReCaptchaResponse
*/
function recaptcha_check_answer($privkey, $remoteip, $challenge, $response, $extra_params = array( ))
{
if( $privkey == null || $privkey == '' )
{
return "Required reCAPTCHA Keys missing from Setup > General Settings > Security";
}
if( $remoteip == null || $remoteip == '' )
{
return "For security reasons, you must pass the remote ip to reCAPTCHA";
}
if( $challenge == null || strlen($challenge) == 0 || $response == null || strlen($response) == 0 )
{
$recaptcha_response = new ReCaptchaResponse();
$recaptcha_response->is_valid = false;
$recaptcha_response->error = 'incorrect-captcha-sol';
return $recaptcha_response;
}
$response = _recaptcha_http_post(RECAPTCHA_VERIFY_SERVER, '/recaptcha/api/verify', array( 'privatekey' => $privkey, 'remoteip' => $remoteip, 'challenge' => $challenge, 'response' => $response ) + $extra_params);
$answers = explode("\n", $response[1]);
$recaptcha_response = new ReCaptchaResponse();
if( trim($answers[0]) == 'true' )
{
$recaptcha_response->is_valid = true;
}
else
{
$recaptcha_response->is_valid = false;
$recaptcha_response->error = $answers[1];
}
return $recaptcha_response;
}
/**
* gets a URL where the user can sign up for reCAPTCHA. If your application
* has a configuration page where you enter a key, you should provide a link
* using this function.
* @param string $domain The domain where the page is hosted
* @param string $appname The name of your application
*/
function recaptcha_get_signup_url($domain = null, $appname = null)
{
return "https://www.google.com/recaptcha/admin/create?" . _recaptcha_qsencode(array( 'domains' => $domain, 'app' => $appname ));
}
function _recaptcha_aes_pad($val)
{
$block_size = 16;
$numpad = $block_size - strlen($val) % $block_size;
return str_pad($val, strlen($val) + $numpad, chr($numpad));
}
function _recaptcha_aes_encrypt($val, $ky)
{
if( !function_exists('mcrypt_encrypt') )
{
exit( "reCAPTCHA Error: To use reCAPTCHA Mailhide, you need to have the mcrypt php module installed." );
}
$mode = MCRYPT_MODE_CBC;
$enc = MCRYPT_RIJNDAEL_128;
$val = _recaptcha_aes_pad($val);
return mcrypt_encrypt($enc, $ky, $val, $mode, '');
}
function _recaptcha_mailhide_urlbase64($x)
{
return strtr(base64_encode($x), "+/", '-_');
}
function recaptcha_mailhide_url($pubkey, $privkey, $email)
{
if( $pubkey == '' || $pubkey == null || $privkey == '' || $privkey == null )
{
exit( "reCAPTCHA Error: To use reCAPTCHA Mailhide, you have to sign up for a public and private key, " . "you can do so at http://www.google.com/recaptcha/mailhide/apikey" );
}
$ky = pack("H*", $privkey);
$cryptmail = _recaptcha_aes_encrypt($email, $ky);
return "http://www.google.com/recaptcha/mailhide/d?k=" . $pubkey . "&c=" . _recaptcha_mailhide_urlbase64($cryptmail);
}
/**
* gets the parts of the email to expose to the user.
* eg, given johndoe@example,com return ['john', "example.com"].
* the email is then displayed as john...@example.com
*/
function _recaptcha_mailhide_email_parts($email)
{
$arr = preg_split("/@/", $email);
if( strlen($arr[0]) <= 4 )
{
$arr[0] = substr($arr[0], 0, 1);
}
else
{
if( strlen($arr[0]) <= 6 )
{
$arr[0] = substr($arr[0], 0, 3);
}
else
{
$arr[0] = substr($arr[0], 0, 4);
}
}
return $arr;
}
/**
* Gets html to display an email address given a public an private key.
* to get a key, go to:
*
* http://www.google.com/recaptcha/mailhide/apikey
*/
function recaptcha_mailhide_html($pubkey, $privkey, $email)
{
$emailparts = _recaptcha_mailhide_email_parts($email);
$url = recaptcha_mailhide_url($pubkey, $privkey, $email);
return htmlentities($emailparts[0]) . "...@" . htmlentities($emailparts[1]);
}