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authorDerek Jones <derek.jones@ellislab.com>2010-03-05 18:22:45 +0100
committerDerek Jones <derek.jones@ellislab.com>2010-03-05 18:22:45 +0100
commitb41032d2df1e63566f1183533b388372538c46d0 (patch)
tree76517ce02bcd19a4acf06845d3fe6a534d199a64
parent99111e3abe02e9a40795fa96f33ea08e492eadcd (diff)
moved CAPTCHA plugin to a helper
-rw-r--r--system/helpers/captcha_helper.php246
-rw-r--r--system/plugins/captcha_pi.php355
-rw-r--r--user_guide/helpers/captcha_helper.html195
3 files changed, 441 insertions, 355 deletions
diff --git a/system/helpers/captcha_helper.php b/system/helpers/captcha_helper.php
new file mode 100644
index 000000000..a58789219
--- /dev/null
+++ b/system/helpers/captcha_helper.php
@@ -0,0 +1,246 @@
+<?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
+ */
+
+// ------------------------------------------------------------------------
+
+/**
+ * CodeIgniter CAPTCHA Helper
+ *
+ * @package CodeIgniter
+ * @subpackage Helpers
+ * @category Helpers
+ * @author ExpressionEngine Dev Team
+ * @link http://codeigniter.com/user_guide/helpers/xml_helper.html
+ */
+
+// ------------------------------------------------------------------------
+
+/**
+ * Create CAPTCHA
+ *
+ * @access public
+ * @param array array of data for the CAPTCHA
+ * @param string path to create the image in
+ * @param string URL to the CAPTCHA image folder
+ * @param string server path to font
+ * @return string
+ */
+if ( ! function_exists('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_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 */ \ No newline at end of file
diff --git a/system/plugins/captcha_pi.php b/system/plugins/captcha_pi.php
deleted file mode 100644
index 7092f28e1..000000000
--- a/system/plugins/captcha_pi.php
+++ /dev/null
@@ -1,355 +0,0 @@
-<?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' => './path/to/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_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
- $this->db->query("DELETE FROM captcha WHERE captcha_time < ".$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_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 */ \ No newline at end of file
diff --git a/user_guide/helpers/captcha_helper.html b/user_guide/helpers/captcha_helper.html
new file mode 100644
index 000000000..297e47e2a
--- /dev/null
+++ b/user_guide/helpers/captcha_helper.html
@@ -0,0 +1,195 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+<head>
+
+<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+<title>CAPTCHA Helper : CodeIgniter User Guide</title>
+
+<style type='text/css' media='all'>@import url('../userguide.css');</style>
+<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' />
+
+<script type="text/javascript" src="../nav/nav.js"></script>
+<script type="text/javascript" src="../nav/prototype.lite.js"></script>
+<script type="text/javascript" src="../nav/moo.fx.js"></script>
+<script type="text/javascript" src="../nav/user_guide_menu.js"></script>
+
+<meta http-equiv='expires' content='-1' />
+<meta http-equiv= 'pragma' content='no-cache' />
+<meta name='robots' content='all' />
+<meta name='author' content='ExpressionEngine Dev Team' />
+<meta name='description' content='CodeIgniter User Guide' />
+
+</head>
+<body>
+
+<!-- START NAVIGATION -->
+<div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div>
+<div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle_darker.jpg" width="154" height="43" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div>
+<div id="masthead">
+<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
+<tr>
+<td><h1>CodeIgniter User Guide Version 1.7.2</h1></td>
+<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td>
+</tr>
+</table>
+</div>
+<!-- END NAVIGATION -->
+
+
+<!-- START BREADCRUMB -->
+<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
+<tr>
+<td id="breadcrumb">
+<a href="http://codeigniter.com/">CodeIgniter Home</a> &nbsp;&#8250;&nbsp;
+<a href="../index.html">User Guide Home</a> &nbsp;&#8250;&nbsp;
+CAPTCHA Helper
+</td>
+<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="codeigniter.com/user_guide/" />Search User Guide&nbsp; <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" />&nbsp;<input type="submit" class="submit" name="sa" value="Go" /></form></td>
+</tr>
+</table>
+<!-- END BREADCRUMB -->
+
+<br clear="all" />
+
+
+<!-- START CONTENT -->
+<div id="content">
+
+
+<h1>CAPTCHA Helper</h1>
+
+<p>The CAPTCHA Helper file contains functions that assist in creating CAPTCHA images.</p>
+
+
+<h2>Loading this Helper</h2>
+
+<p>This helper is loaded using the following code:</p>
+<code>$this->load->helper('captcha');</code>
+
+<p>The following functions are available:</p>
+
+<h2>captcha_create(<var>$data</var>)</h2>
+
+<p>Takes an array of information to generate the CAPTCHA as input and creates the image to your specifications, returning an array of associative data about the image.</p>
+
+<code>[array]<br />
+(<br />
+&nbsp;&nbsp;'image' => IMAGE TAG<br />
+&nbsp;&nbsp;'time' => TIMESTAMP (in microtime)<br />
+&nbsp;&nbsp;'word' => CAPTCHA WORD<br />
+)</code>
+
+ <p>The "image" is the actual image tag:
+<code>&lt;img src=&quot;http://example.com/captcha/12345.jpg&quot; width=&quot;140&quot; height=&quot;50&quot; /&gt;</code></p>
+
+ <p>The "time" is the micro timestamp used as the image name without the file
+ extension. It will be a number like this: 1139612155.3422</p>
+
+ <p>The "word" is the word that appears in the captcha image, which if not
+ supplied to the function, will be a random string.</p>
+
+ <h3>Using the CAPTCHA plugin</h3>
+
+ <p>Once loaded you can generate a captcha like this:</p>
+
+<code>$vals = array(<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'word' => 'Random word',<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'img_path' => './captcha/',<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'img_url' => 'http://example.com/captcha/',<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'font_path' => './path/to/fonts/texb.ttf',<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'img_width' => '150',<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'img_height' => 30,<br />
+&nbsp;&nbsp;&nbsp;&nbsp;'expiration' => 7200<br />
+&nbsp;&nbsp;&nbsp;&nbsp;);<br />
+<br />
+$cap = create_captcha($vals);<br />
+echo $cap['image'];</code>
+
+ <ul>
+ <li>The captcha function requires the GD image library.</li>
+ <li>Only the img_path and img_url are required.</li>
+ <li>If a "word" is not supplied, the function will generate a random
+ ASCII string. You might put together your own word library that
+ you can draw randomly from.</li>
+ <li>If you do not specify a path to a TRUE TYPE font, the native ugly GD
+ font will be used.</li>
+ <li>The "captcha" folder must be writable (666, or 777)</li>
+ <li>The "expiration" (in seconds) signifies how long an image will
+ remain in the captcha folder before it will be deleted. The default
+ is two hours.</li>
+ </ul>
+
+ <h3>Adding a Database</h3>
+
+ <p>In order for the captcha function to prevent someone from submitting, you will need
+ to add the information returned from <kbd>create_captcha()</kbd> function to your database.
+ Then, when the data from the form is submitted by the user you will need to verify
+ that the data exists in the database and has not expired.</p>
+
+ <p>Here is a table prototype:</p>
+
+<code>CREATE TABLE captcha (<br />
+&nbsp;captcha_id bigint(13) unsigned NOT NULL auto_increment,<br />
+&nbsp;captcha_time int(10) unsigned NOT NULL,<br />
+&nbsp;ip_address varchar(16) default '0' NOT NULL,<br />
+&nbsp;word varchar(20) NOT NULL,<br />
+&nbsp;PRIMARY KEY `captcha_id` (`captcha_id`),<br />
+&nbsp;KEY `word` (`word`)<br />
+)</code>
+
+ <p>Here is an example of usage with a database. On the page where the CAPTCHA will be shown you'll have something like this:</p>
+
+<code>$this-&gt;load-&gt;plugin(&#x27;captcha&#x27;);<br />
+$vals = array(<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&#x27;img_path&#x27; =&gt; &#x27;./captcha/&#x27;,<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&#x27;img_url&#x27; =&gt; &#x27;http://example.com/captcha/&#x27;<br />
+&nbsp;&nbsp;&nbsp;&nbsp;);<br />
+<br />
+$cap = create_captcha($vals);<br />
+<br />
+$data = array(<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&#x27;captcha_time&#x27; =&gt; $cap[&#x27;time&#x27;],<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&#x27;ip_address&#x27; =&gt; $this-&gt;input-&gt;ip_address(),<br />
+&nbsp;&nbsp;&nbsp;&nbsp;&#x27;word&#x27; =&gt; $cap[&#x27;word&#x27;]<br />
+&nbsp;&nbsp;&nbsp;&nbsp;);<br />
+<br />
+$query = $this-&gt;db-&gt;insert_string(&#x27;captcha&#x27;, $data);<br />
+$this-&gt;db-&gt;query($query);<br />
+<br />
+echo &#x27;Submit the word you see below:&#x27;;<br />
+echo $cap[&#x27;image&#x27;];<br />
+echo &#x27;&lt;input type=&quot;text&quot; name=&quot;captcha&quot; value=&quot;&quot; /&gt;&#x27;;</code>
+
+ <p>Then, on the page that accepts the submission you'll have something like this:</p>
+
+<code>// First, delete old captchas<br />
+$expiration = time()-7200; // Two hour limit<br />
+$this-&gt;db-&gt;query(&quot;DELETE FROM captcha WHERE captcha_time &lt; &quot;.$expiration); <br />
+<br />
+// Then see if a captcha exists:<br />
+$sql = &quot;SELECT COUNT(*) AS count FROM captcha WHERE word = ? AND ip_address = ? AND date &gt; ?&quot;;<br />
+$binds = array($_POST[&#x27;captcha&#x27;], $this-&gt;input-&gt;ip_address(), $expiration);<br />
+$query = $this-&gt;db-&gt;query($sql, $binds);<br />
+$row = $query-&gt;row();<br />
+<br />
+if ($row-&gt;count == 0)<br />
+{<br />
+&nbsp;&nbsp;&nbsp;&nbsp;echo &quot;You must submit the word that appears in the image&quot;;<br />
+}</code>
+
+</div>
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