Miscellaneous Hacks - reCAPTCHA!vB

THIS MODIFICATION SHOULD NOT BE USED WITH VBULLETIN 3.7+ AS IT IS A DEFAULT FEATURE.

Keywords: reCAPTCHA, CAPTCHA, spam, register

Description:
This modification will replaced the default vBulletin registration CAPTCHA with the newer, more advanced reCAPTCHA.

What is CAPTCHA/reCAPTCHA?:
A CAPTCHA is a program that can tell whether its user is a human or a computer. You've probably seen them ? colorful images with distorted text at the bottom of Web registration forms. CAPTCHAs are used by many websites to prevent abuse from "bots," or automated programs usually written to generate spam. No computer program can read distorted text as well as humans can, so bots cannot navigate sites protected by CAPTCHAs.

About 60 million CAPTCHAs are solved by humans around the world every day. In each case, roughly ten seconds of human time are being spent. Individually, that's not a lot of time, but in aggregate these little puzzles consume more than 150,000 hours of work each day. What if we could make positive use of this human effort? reCAPTCHA does exactly that by channeling the effort spent solving CAPTCHAs online into "reading" books.

To archive human knowledge and to make information more accessible to the world, multiple projects are currently digitizing physical books that were written before the computer age. The book pages are being photographically scanned, and then, to make them searchable, transformed into text using "Optical Character Recognition" (OCR). The transformation into text is useful because scanning a book produces images, which are difficult to store on small devices, expensive to download, and cannot be searched. The problem is that OCR is not perfect.



reCAPTCHA improves the process of digitizing books by sending words that cannot be read by computers to the Web in the form of CAPTCHAs for humans to decipher. More specifically, each word that cannot be read correctly by OCR is placed on an image and used as a CAPTCHA. This is possible because most OCR programs alert you when a word cannot be read correctly.

But if a computer can't read such a CAPTCHA, how does the system know the correct answer to the puzzle? Here's how: Each new word that cannot be read correctly by OCR is given to a user in conjunction with another word for which the answer is already known. The user is then asked to read both words. If they solve the one for which the answer is known, the system assumes their answer is correct for the new one. The system then gives the new image to a number of other people to determine, with higher confidence, whether the original answer was correct.

Currently, we are helping to digitize books from the Internet Archive.

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Installation:

1. Download and unzip the recaptcha101.zip archive.
2. Upload the functions_recaptcha.php to your /includes/ directory.
3. Import the product-recaptcha.xml via the Product Manager.
4. Obtain a FREE public and private reCAPTCHA key here.
5. Make any desired configuration changes via AdminCP > vBulletin Options > reCAPTCHA Options
6. Make a backup of your register.php file, located in your forum root.
7. Perform ONE (1) of the following methods:
   • Method A:
     • Download the register-patch.zip archive, extract, then upload the register.patch file to your forum root, then apply the patch:
       
       *Note: Please note that this method requires a basic understanding of UNIX shell commands and requires shell access to your host. If you do not have either of these or you are unsure how to use GNU patch, I highly suggest performing Method B instead)
       
       

       # patch -b register.php < register.patch

       This will perform the file edits automatically. Once finished, you may delete the register.patch file.
   • Method B:
     Perform the following simple file edits:
     • IN register.php:
       1. FIND:
          
          PHP Code:

          eval('$imagereg = "' . fetch_template('imagereg') . '";'); 

          REPLACE WITH:
          
          PHP Code:

          $imagereg = recaptcha_get_html($vbulletin->options['recaptcha_publickey'], $error); 

       2. FIND AND REMOVE:
          
          PHP Code:

                          'imagestamp'          => TYPE_STR,
                'imagehash'           => TYPE_STR, 

       3. FIND:
          
          PHP Code:

                  // Check Reg Image
        if ($vbulletin->options['regimagecheck'] AND $vbulletin->options['regimagetype'])
        {
                require_once(DIR . '/includes/functions_regimage.php');
                if (!verify_regimage_hash($vbulletin->GPC['imagehash'], $vbulletin->GPC['imagestamp']))
                {
                        $userdata->error('register_imagecheck');
                }
        } 

          REPLACE WITH:
          
          PHP Code:

                  // Check Reg Image
        if ($vbulletin->options['regimagecheck'] AND $vbulletin->options['regimagetype'])
        {
                $resp = recaptcha_check_answer ($vbulletin->options['recaptcha_privatekey'],
                                                $_SERVER["REMOTE_ADDR"],
                                                $_POST["recaptcha_challenge_field"],
                                                $_POST["recaptcha_response_field"]);

                if (!$resp->is_valid)
                {
                        $userdata->error('register_imagecheck');
                }
        } 


NOTE: YOU MAY ALSO REPLACE THE CAPTCHA DISPLAYED TO GUESTS WHEN USING THE "CONTACT US" FORM BY FOLLOWING THE INSTRUCTIONS HERE.

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Tips, tricks and modifications:

• Apply "Method A" without shell access (DOCTOR DAN)
• Restore "image verification" frame around reCAPTCHA panel (DOCTOR DAN)

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Comments:
As with all my hacks, this modification is provided free of charge. However, if you find this product useful and have money burning a hole in your pocket, feel free to make a small donation, I won't mind.. really.

Version History:

• 1.0.0 - Initial release, here's to hoping...
• 1.0.1 - Woops! Forgot to include a aesthetic template edit in the original release. All is well, simply redownload and overwrite the XML. That's it!
• 1.1.0 - Added alternate language support. Now various reCAPTCHA tags and text will be displayed in your selected language. Also added a fieldset to the automatic template edits around the display block for a more uniform look (thanks DOCTOR DAN!).

Currently Known Bugs:

• None

* Please note that this modification was developed on a forum with a userbase of 1 (myself). I've tested it for basic functionality but I cannot guarantee functionality or behavior on your forum. So, please -- make backups before installing this product!

[Smoothie]

Installed, not having much luck changing themes. Is that theme dropdown suppose to work?

Edit: Ok, I tried the 3 themes and the only that shows for me is that butt-ugly red one.

[magnus]

If you're having a problem with themes, chances are the automatic template edit isn't taking effect. Simply make the edit manually.

In the register template:

• FIND:
  

  			$imagereg

  REPLACE WITH::
  

  			<script type='text/javascript'>
  			var RecaptchaOptions = {
  			   theme : "$vboptions[recaptcha_theme]",
  			   tabindex : $vboptions[recaptcha_tabindex]
  			};
  			</script>
  
  			$imagereg

And, just for good measure you might want to disable the automatic template edit plugin. In AdminCP > Plugins & Products > Plugin Manager look for Automatically modify register template (located under reCAPTCHA!vB) and uncheck the box, then click "Save Active Status".

That should do it!

[Alibass]

@magnus

Thank you for posting instructions here on how to make captcha work for guest using "Contact Us" form.

Works great and thanks again.

[kayakbabe]

Would be absolutely great if this could also be used by registred users for things like replies, quick replies, new threads, etc. Even better if it could be used for registered users with less than x postings to their credit. So that it will help drive those manual spammers away.

[magnus]

Why would you want registered users to be subjected to CAPTCHA's?

[pitzerwm]

I think that I followed all of the instructions but when I click on "register" it does go to /register.php but its blank. I replace it with the original and its ok. I did the upload etc. and added the keys to the product in the appropriate spaces. I have double and triple checked my typing. Any suggestions?

Thanks

// Check Reg Image
if ($vbulletin->options['regimagecheck'] AND $vbulletin->options['regimagetype'])
{
$resp = recaptcha_check_answer ($vbulletin->options['recaptcha_privatekey'],
$_SERVER["REMOTE_ADDR"],
$_POST["recaptcha_challenge_field"],
$_POST["recaptcha_response_field"];

if (!$resp->is_valid)
{
$userdata->error('register_imagecheck');
}
}

if ($vbulletin->options['regimagecheck'] AND $vbulletin->options['regimagetype'])
{
$imagereg = recaptcha_get_html
($vbulletin->options['recaptcha_publickey'],
$error);
}
else
{
$imagereg = '';
}

[magnus]

Originally Posted by pitzerwm

I think that I followed all of the instructions but when I click on "register" it does go to /register.php but its blank. I replace it with the original and its ok. I did the upload etc. and added the keys to the product in the appropriate spaces. I have double and triple checked my typing. Any suggestions?

Thanks

You're missing a close bracket ')' in the following block (highlighted in red):

// Check Reg Image
	if ($vbulletin->options['regimagecheck'] AND $vbulletin->options['regimagetype'])
	{
		$resp = recaptcha_check_answer ($vbulletin->options['recaptcha_privatekey'],
		$_SERVER["REMOTE_ADDR"],
		$_POST["recaptcha_challenge_field"],
		$_POST["recaptcha_response_field"]);
		
		if (!$resp->is_valid)
		{
		$userdata->error('register_imagecheck');
		}
	}

Also, why are you typing out the code changes manually? Just copy and paste them from the original post to make sure there are no typo's and to retain proper formatting.

[pitzerwm]

Thanks for your help, I knew that it was something stupid. Works great now. I guess that it was midnight, that I didn't think to cut & paste.

[Caerydd]

Love this method, love this hack, works flawlessly so far, and much more in keeping with my board ^^

Go you!

[magnus]

Originally Posted by Caerydd

Love this method, love this hack, works flawlessly so far, and much more in keeping with my board ^^

Go you!

Glad you like it!