mediawiki-extensions-ConfirmEdit/ReCaptcha.php

<?php

/**
 * Captcha class using the reCAPTCHA widget.
 * Stop Spam. Read Books.
 *
 * @addtogroup Extensions
 * @author Mike Crawford <mike.crawford@gmail.com>
 * @copyright Copyright (c) 2007 reCAPTCHA -- http://recaptcha.net
 * @licence MIT/X11
 */

if ( !defined( 'MEDIAWIKI' ) ) {
	exit;
}

require_once dirname( __FILE__ ) . '/ConfirmEdit.php';
$wgCaptchaClass = 'ReCaptcha';

$wgExtensionMessagesFiles['ReCaptcha'] = dirname( __FILE__ ) . '/ReCaptcha.i18n.php';

require_once( 'recaptchalib.php' );

// Set these in LocalSettings.php
$wgReCaptchaPublicKey = '';
$wgReCaptchaPrivateKey = '';
// For backwards compatibility
$recaptcha_public_key = '';
$recaptcha_private_key = '';

/**
 * Sets the theme for ReCaptcha
 *
 * See http://code.google.com/apis/recaptcha/docs/customization.html
 */
$wgReCaptchaTheme = 'red';

$wgExtensionFunctions[] = 'efReCaptcha';

/**
 * Make sure the keys are defined.
 */
function efReCaptcha() {
	global $wgReCaptchaPublicKey, $wgReCaptchaPrivateKey;
	global $recaptcha_public_key, $recaptcha_private_key;
	global $wgServerName;

	// Backwards compatibility
	if ( $wgReCaptchaPublicKey == '' ) {
		$wgReCaptchaPublicKey = $recaptcha_public_key;
	}
	if ( $wgReCaptchaPrivateKey == '' ) {
		$wgReCaptchaPrivateKey = $recaptcha_private_key;
	}

	if ($wgReCaptchaPublicKey == '' || $wgReCaptchaPrivateKey == '') {
		die ('You need to set $wgReCaptchaPrivateKey and $wgReCaptchaPublicKey in LocalSettings.php to ' .
			"use the reCAPTCHA plugin. You can sign up for a key <a href='" .
			htmlentities(recaptcha_get_signup_url ($wgServerName, "mediawiki")) . "'>here</a>.");
	}
}


class ReCaptcha extends SimpleCaptcha {

	//reCAPTHCA error code returned from recaptcha_check_answer
	private $recaptcha_error = null;

	/**
	 * Displays the reCAPTCHA widget.
	 * If $this->recaptcha_error is set, it will display an error in the widget.
	 *
	 */
	function getForm() {
		global $wgReCaptchaPublicKey, $wgReCaptchaTheme;
		$useHttps = ( isset( $_SERVER['HTTPS'] ) && $_SERVER['HTTPS'] == 'on' );
		$js = 'var RecaptchaOptions = ' . Xml::encodeJsVar( array( 'theme' => $wgReCaptchaTheme, 'tabindex' => 1  ) );

		return Html::inlineScript( $js ) . recaptcha_get_html($wgReCaptchaPublicKey, $this->recaptcha_error, $useHttps);
	}

	/**
	 * Calls the library function recaptcha_check_answer to verify the users input.
	 * Sets $this->recaptcha_error if the user is incorrect.
	 * @return boolean
	 *
	 */
	function passCaptcha() {
		global $wgReCaptchaPrivateKey, $wgRequest;

		//API is hardwired to return wpCaptchaId and wpCaptchaWord, so use that if the standard two are empty
		$challenge = $wgRequest->getVal( 'recaptcha_challenge_field', $wgRequest->getVal( 'wpCaptchaId' ) );
		$response = $wgRequest->getVal( 'recaptcha_response_field', $wgRequest->getVal( 'wpCaptchaWord' ) );
		
		if ( $response === null ) {
			//new captcha session
			return false;
		}

		$recaptcha_response = recaptcha_check_answer(
			$wgReCaptchaPrivateKey,
			$wgRequest->getIP(),
			$challenge,
			$response
		);
		
		if (!$recaptcha_response->is_valid) {
			$this->recaptcha_error = $recaptcha_response->error;
			return false;
		}
		
		$recaptcha_error = null;
		
		return true;

	}

	function addCaptchaAPI( &$resultArr ) {
		global $wgReCaptchaPublicKey;
		$resultArr['captcha']['type'] = 'recaptcha';
		$resultArr['captcha']['mime'] = 'image/png';
		$resultArr['captcha']['key'] = $wgReCaptchaPublicKey;
		$resultArr['captcha']['error'] = $this->recaptcha_error;
	}

	/**
	 * Show a message asking the user to enter a captcha on edit
	 * The result will be treated as wiki text
	 *
	 * @param $action Action being performed
	 * @return string
	 */
	function getMessage( $action ) {
		$name = 'recaptcha-' . $action;
		$text = wfMsg( $name );
		# Obtain a more tailored message, if possible, otherwise, fall back to
		# the default for edits
		return wfEmptyMsg( $name, $text ) ? wfMsg( 'recaptcha-edit' ) : $text;
	}

	public function APIGetAllowedParams( &$module, &$params ) {
		return true;
	}

	public function APIGetParamDescription( &$module, &$desc ) {
		return true;
	}
}