ReCAPTCHA

Category:Libraries Category:Libraries::reCAPTCHA

This is a CI implementation of the ReCAPTCHA server (http://www.recaptcha.net)

There are three files needed:

1. /application/config/recaptcha.php
2. /application/libraries/Recaptcha.php
3. /application/views/recaptcha.php

config: [code] $config['recaptcha'] = array( 'public'=>'your_key_here', 'private'=>'your_key_here', 'RECAPTCHA_API_SERVER' =>'http://api.recaptcha.net', 'RECAPTCHA_API_SECURE_SERVER'=>'https://api-secure.recaptcha.net', 'RECAPTCHA_VERIFY_SERVER' =>'api-verify.recaptcha.net', 'theme' => 'red' ); [/code]

library: [code] <?php if (!defined('BASEPATH')) exit('No direct script access allowed'); /*

• This is a PHP library that handles calling reCAPTCHA.
• • Documentation and latest version

•      http://recaptcha.net/plugins/php/
  

• • Get a reCAPTCHA API Key

•      http://recaptcha.net/api/getkey
  

• • Discussion group

•      http://groups.google.com/group/recaptcha
  

• Copyright (c) 2007 reCAPTCHA -- http://recaptcha.net
• AUTHORS:
• Mike Crawford
• Ben Maurer
• Permission is hereby granted, free of charge, to any person obtaining a copy
• of this software and associated documentation files (the "Software"), to deal
• in the Software without restriction, including without limitation the rights
• to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
• copies of the Software, and to permit persons to whom the Software is
• furnished to do so, subject to the following conditions:
• The above copyright notice and this permission notice shall be included in
• all copies or substantial portions of the Software.
• THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
• IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
• FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
• AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
• LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
• OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
• THE SOFTWARE. */

/**

• Recaptcha modified to integrate easily with Code Igniter

• @package CodeIgniter

• @subpackage Libraries

• @category Captcha

• @author Jon Trelfa [email protected]

• @link none yet */ class Recaptcha {

  //private var $_rConfig; var $_ci;

  //public var $is_valid; var $error;

  //set the default URLs for using Recaptcha function __construct() { log_message('debug', 'Recaptcha class Initialized'); $this->_ci =& get_instance(); $this->_ci->config->load('recaptcha'); $this->_rConfig = $this->_ci->config->item('recaptcha'); $this->is_valid = false; $this->error = ''; }

  /**

  • Encodes the given data into a query string format
  • @param $data - array of string elements to be encoded
  • @return string - encoded request */ function _recaptcha_qsencode($data) { return http_build_query($data); }

  /**

  • 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 = $this->_recaptcha_qsencode($data); $http_request = implode('',array( "POST $path HTTP/1.0\r\n", "Host: $host\r\n", "Content-Type: application/x-www-form-urlencoded;\r\n", "Content-Length:".strlen($req)."\r\n", "User-Agent: reCAPTCHA/PHP\r\n", "\r\n", $req)); $response = ''; if( false == ( $fs = @fsockopen($host, $port, $errno, $errstr, 10) ) ) { show_error('Could not open socket'); }

  fwrite($fs, $http_request); while (!feof($fs)) { $response .= fgets($fs, 1160); // One TCP-IP packet } 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 ($error = null, $use_ssl = false) { if ($this->_rConfig['public'] == '') { show_error("To use reCAPTCHA you must get an API key from http://recaptcha.net/api/getkey"); }

    if ($use_ssl) { $server = $this->_rConfig['RECAPTCHA_API_SECURE_SERVER']; } else { $server = $this->_rConfig['RECAPTCHA_API_SERVER']; }

  $errorpart = ""; if ($error) { $errorpart = "&error=" . $error; } $data = array( 'server'=>$server, 'key'=>$this->_rConfig['public'], 'theme'=>$this->_rConfig['theme'], 'errorpart'=>$errorpart ); return $this->_ci->load->view('recaptcha',$data,true); }

  /**

  • 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, $appname = null) { return "http://recaptcha.net/api/getkey?".$this->_recaptcha_qsencode(array ('domain' => $domain, 'app' => $appname)); }

  /**

  • 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 ($remoteip, $challenge, $response, $extra_params = array()) { if ($this->_rConfig['private'] == '') { die ("To use reCAPTCHA you must get an API key from http://recaptcha.net/api/getkey"); }

    if ($remoteip == null || $remoteip == '') { show_error("For security reasons, you must pass the remote ip to reCAPTCHA"); }

  //discard spam submissions if ($challenge == null || strlen($challenge) == 0 || $response == null || strlen($response) == 0) { $this->is_valid = false; $this->error = 'incorrect-captcha-sol'; return; }

  $response = $this->_recaptcha_http_post( $this->_rConfig['RECAPTCHA_VERIFY_SERVER'], "/verify", array ( 'privatekey' => $this->_rConfig['private'], 'remoteip' => $remoteip, 'challenge' => $challenge, 'response' => $response ) + $extra_params ); //show_error($response);

  $answers = explode ("\n", $response [1]);

  if (trim ($answers [0]) == 'true') { $this->is_valid = true; } else { $this->is_valid = false; $this->error = $answers [1]; } return; }

} ?> [/code]

view:[code]

<script type="text/javascript"> var RecaptchaOptions = { theme:"<?= $theme ?>" }; </script> <script type="text/javascript" src="<?= $server ?>/challenge?k=<?= $key . $errorpart?>"></script>

<iframe src="<?= $server ?>/noscript?k=<?= $key.$errorpart ?>" height="300" width="500" frameborder="0"></iframe>
<textarea name="recaptcha_challenge_field" rows="3" cols="40"></textarea> <input type="hidden" name="recaptcha_response_field" value="manual_challenge"/> [/code] Usage:

In your controller, you do the following: [code] $this->load->library('recaptcha'); $data = array( 'captcha' => $this->recaptcha->recaptcha_get_html() );

// Add the following to regular form validation Rules $rules = array( 'recaptcha_response_field'=>'required|callback_check_captcha' );

$this->validation->set_rules($rules);

// Function to check to see if captcha is correctly submitted

function check_captcha($val) { $this->recaptcha->recaptcha_check_answer($_SERVER["REMOTE_ADDR"],$this->input->post('recaptcha_challenge_field'),$val); if ($this->recaptcha->is_valid) { return true; } else { $this->validation->set_message('check_captcha','Incorrect Security Image Response'); return false; } }

// Load the view and $data as per normal $this->load->view('view_name',$data); [/code]

In your view: [code] <?PHP echo $captcha ?> [/code]

That's it :)