| <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); |
| /** |
| * CodeIgniter |
| * |
| * An open source application development framework for PHP 4.3.2 or newer |
| * |
| * @package CodeIgniter |
| * @author ExpressionEngine Dev Team |
| * @copyright Copyright (c) 2008 - 2010, EllisLab, Inc. |
| * @license http://codeigniter.com/user_guide/license.html |
| * @link http://codeigniter.com |
| * @since Version 1.0 |
| * @filesource |
| */ |
| |
| // ------------------------------------------------------------------------ |
| |
| /* |
| Instructions: |
| |
| Load the plugin using: |
| |
| $this->load->plugin('captcha'); |
| |
| Once loaded you can generate a captcha like this: |
| |
| $vals = array( |
| 'word' => 'Random word', |
| 'img_path' => './captcha/', |
| 'img_url' => 'http://example.com/captcha/', |
| 'font_path' => './system/fonts/texb.ttf', |
| 'img_width' => '150', |
| 'img_height' => 30, |
| 'expiration' => 7200 |
| ); |
| |
| $cap = create_captcha($vals); |
| echo $cap['image']; |
| |
| |
| NOTES: |
| |
| The captcha function requires the GD image library. |
| |
| Only the img_path and img_url are required. |
| |
| If a "word" is not supplied, the function will generate a random |
| ASCII string. You might put together your own word library that |
| you can draw randomly from. |
| |
| If you do not specify a path to a TRUE TYPE font, the native ugly GD |
| font will be used. |
| |
| The "captcha" folder must be writable (666, or 777) |
| |
| The "expiration" (in seconds) signifies how long an image will |
| remain in the captcha folder before it will be deleted. The default |
| is two hours. |
| |
| RETURNED DATA |
| |
| The create_captcha() function returns an associative array with this data: |
| |
| [array] |
| ( |
| 'image' => IMAGE TAG |
| 'time' => TIMESTAMP (in microtime) |
| 'word' => CAPTCHA WORD |
| ) |
| |
| The "image" is the actual image tag: |
| <img src="http://example.com/captcha/12345.jpg" width="140" height="50" /> |
| |
| The "time" is the micro timestamp used as the image name without the file |
| extension. It will be a number like this: 1139612155.3422 |
| |
| The "word" is the word that appears in the captcha image, which if not |
| supplied to the function, will be a random string. |
| |
| |
| ADDING A DATABASE |
| |
| In order for the captcha function to prevent someone from posting, you will need |
| to add the information returned from create_captcha() function to your database. |
| Then, when the data from the form is submitted by the user you will need to verify |
| that the data exists in the database and has not expired. |
| |
| Here is a table prototype: |
| |
| CREATE TABLE captcha ( |
| captcha_id bigint(13) unsigned NOT NULL auto_increment, |
| captcha_time int(10) unsigned NOT NULL, |
| ip_address varchar(16) default '0' NOT NULL, |
| word varchar(20) NOT NULL, |
| PRIMARY KEY `captcha_id` (`captcha_id`), |
| KEY `word` (`word`) |
| ) |
| |
| |
| Here is an example of usage with a DB. |
| |
| On the page where the captcha will be shown you'll have something like this: |
| |
| $this->load->plugin('captcha'); |
| $vals = array( |
| 'img_path' => './captcha/', |
| 'img_url' => 'http://example.com/captcha/' |
| ); |
| |
| $cap = create_captcha($vals); |
| |
| $data = array( |
| 'captcha_id' => '', |
| 'captcha_time' => $cap['time'], |
| 'ip_address' => $this->input->ip_address(), |
| 'word' => $cap['word'] |
| ); |
| |
| $query = $this->db->insert_string('captcha', $data); |
| $this->db->query($query); |
| |
| echo 'Submit the word you see below:'; |
| echo $cap['image']; |
| echo '<input type="text" name="captcha" value="" />'; |
| |
| |
| Then, on the page that accepts the submission you'll have something like this: |
| |
| // First, delete old captchas |
| $expiration = time()-7200; // Two hour limit |
| $DB->query("DELETE FROM captcha WHERE captcha_time < ".$expiration); |
| |
| // Then see if a captcha exists: |
| $sql = "SELECT COUNT(*) AS count FROM captcha WHERE word = ? AND ip_address = ? AND date > ?"; |
| $binds = array($_POST['captcha'], $this->input->ip_address(), $expiration); |
| $query = $this->db->query($sql, $binds); |
| $row = $query->row(); |
| |
| if ($row->count == 0) |
| { |
| echo "You must submit the word that appears in the image"; |
| } |
| |
| */ |
| |
| |
| |
| /** |
| |========================================================== |
| | Create Captcha |
| |========================================================== |
| | |
| */ |
| function create_captcha($data = '', $img_path = '', $img_url = '', $font_path = '') |
| { |
| $defaults = array('word' => '', 'img_path' => '', 'img_url' => '', 'img_width' => '150', 'img_height' => '30', 'font_path' => '', 'expiration' => 7200); |
| |
| foreach ($defaults as $key => $val) |
| { |
| if ( ! is_array($data)) |
| { |
| if ( ! isset($$key) OR $$key == '') |
| { |
| $$key = $val; |
| } |
| } |
| else |
| { |
| $$key = ( ! isset($data[$key])) ? $val : $data[$key]; |
| } |
| } |
| |
| if ($img_path == '' OR $img_url == '') |
| { |
| return FALSE; |
| } |
| |
| if ( ! @is_dir($img_path)) |
| { |
| return FALSE; |
| } |
| |
| if ( ! is_really_writable($img_path)) |
| { |
| return FALSE; |
| } |
| |
| if ( ! extension_loaded('gd')) |
| { |
| return FALSE; |
| } |
| |
| // ----------------------------------- |
| // Remove old images |
| // ----------------------------------- |
| |
| list($usec, $sec) = explode(" ", microtime()); |
| $now = ((float)$usec + (float)$sec); |
| |
| $current_dir = @opendir($img_path); |
| |
| while($filename = @readdir($current_dir)) |
| { |
| if ($filename != "." and $filename != ".." and $filename != "index.html") |
| { |
| $name = str_replace(".jpg", "", $filename); |
| |
| if (($name + $expiration) < $now) |
| { |
| @unlink($img_path.$filename); |
| } |
| } |
| } |
| |
| @closedir($current_dir); |
| |
| // ----------------------------------- |
| // Do we have a "word" yet? |
| // ----------------------------------- |
| |
| if ($word == '') |
| { |
| $pool = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; |
| |
| $str = ''; |
| for ($i = 0; $i < 8; $i++) |
| { |
| $str .= substr($pool, mt_rand(0, strlen($pool) -1), 1); |
| } |
| |
| $word = $str; |
| } |
| |
| // ----------------------------------- |
| // Determine angle and position |
| // ----------------------------------- |
| |
| $length = strlen($word); |
| $angle = ($length >= 6) ? rand(-($length-6), ($length-6)) : 0; |
| $x_axis = rand(6, (360/$length)-16); |
| $y_axis = ($angle >= 0 ) ? rand($img_height, $img_width) : rand(6, $img_height); |
| |
| // ----------------------------------- |
| // Create image |
| // ----------------------------------- |
| |
| // PHP.net recommends imagecreatetruecolor(), but it isn't always available |
| if (function_exists('imagecreatetruecolor')) |
| { |
| $im = imagecreatetruecolor($img_width, $img_height); |
| } |
| else |
| { |
| $im = imagecreate($img_width, $img_height); |
| } |
| |
| // ----------------------------------- |
| // Assign colors |
| // ----------------------------------- |
| |
| $bg_color = imagecolorallocate ($im, 255, 255, 255); |
| $border_color = imagecolorallocate ($im, 153, 102, 102); |
| $text_color = imagecolorallocate ($im, 204, 153, 153); |
| $grid_color = imagecolorallocate($im, 255, 182, 182); |
| $shadow_color = imagecolorallocate($im, 255, 240, 240); |
| |
| // ----------------------------------- |
| // Create the rectangle |
| // ----------------------------------- |
| |
| ImageFilledRectangle($im, 0, 0, $img_width, $img_height, $bg_color); |
| |
| // ----------------------------------- |
| // Create the spiral pattern |
| // ----------------------------------- |
| |
| $theta = 1; |
| $thetac = 7; |
| $radius = 16; |
| $circles = 20; |
| $points = 32; |
| |
| for ($i = 0; $i < ($circles * $points) - 1; $i++) |
| { |
| $theta = $theta + $thetac; |
| $rad = $radius * ($i / $points ); |
| $x = ($rad * cos($theta)) + $x_axis; |
| $y = ($rad * sin($theta)) + $y_axis; |
| $theta = $theta + $thetac; |
| $rad1 = $radius * (($i + 1) / $points); |
| $x1 = ($rad1 * cos($theta)) + $x_axis; |
| $y1 = ($rad1 * sin($theta )) + $y_axis; |
| imageline($im, $x, $y, $x1, $y1, $grid_color); |
| $theta = $theta - $thetac; |
| } |
| |
| // ----------------------------------- |
| // Write the text |
| // ----------------------------------- |
| |
| $use_font = ($font_path != '' AND file_exists($font_path) AND function_exists('imagettftext')) ? TRUE : FALSE; |
| |
| if ($use_font == FALSE) |
| { |
| $font_size = 5; |
| $x = rand(0, $img_width/($length/3)); |
| $y = 0; |
| } |
| else |
| { |
| $font_size = 16; |
| $x = rand(0, $img_width/($length/1.5)); |
| $y = $font_size+2; |
| } |
| |
| for ($i = 0; $i < strlen($word); $i++) |
| { |
| if ($use_font == FALSE) |
| { |
| $y = rand(0 , $img_height/2); |
| imagestring($im, $font_size, $x, $y, substr($word, $i, 1), $text_color); |
| $x += ($font_size*2); |
| } |
| else |
| { |
| $y = rand($img_height/2, $img_height-3); |
| imagettftext($im, $font_size, $angle, $x, $y, $text_color, $font_path, substr($word, $i, 1)); |
| $x += $font_size; |
| } |
| } |
| |
| |
| // ----------------------------------- |
| // Create the border |
| // ----------------------------------- |
| |
| imagerectangle($im, 0, 0, $img_width-1, $img_height-1, $border_color); |
| |
| // ----------------------------------- |
| // Generate the image |
| // ----------------------------------- |
| |
| $img_name = $now.'.jpg'; |
| |
| ImageJPEG($im, $img_path.$img_name); |
| |
| $img = "<img src=\"$img_url$img_name\" width=\"$img_width\" height=\"$img_height\" style=\"border:0;\" alt=\" \" />"; |
| |
| ImageDestroy($im); |
| |
| return array('word' => $word, 'time' => $now, 'image' => $img); |
| } |
| |
| |
| /* End of file captcha_pi.php */ |
| /* Location: ./system/plugins/captcha_pi.php */ |