Changeset 3031

Timestamp:

07/10/2008 11:06:23 AM (3 months ago)

Author:

Geert

Message:

A few minor tweaks to Basic and Alpha Captcha style in order to preserve enough readability and make both styles differ a bit more.

Also changed internal terminology to the "official" convention: http://en.wikipedia.org/wiki/Challenge-response_authentication

Location:

trunk

Files:

• application/controllers/examples.php (modified) (2 diffs)
• system/config/captcha.php (modified) (2 diffs)
• system/libraries/Captcha.php (modified) (3 diffs)
• system/libraries/drivers/Captcha/Alpha.php (modified) (4 diffs)
• system/libraries/drivers/Captcha/Basic.php (modified) (3 diffs)

trunk/application/controllers/examples.php

@@ -176 +176 @@
         {
                 // Form submitted
-                if (isset($_POST['captcha_answer']))
+                if (isset($_POST['captcha_response']))
                 {
                         // Note: Captcha::valid() can be used in conjunction with the Validation library too
-                        echo (Captcha::valid($_POST['captcha_answer'])) ? 'Good answer!' : 'Wrong answer!';
+                        echo (Captcha::valid($_POST['captcha_response'])) ? 'Good answer!' : 'Wrong answer!';
                 }
 
@@ -187 +187 @@
                 echo Captcha::factory()->render(); // <-- shows the Captcha challenge (image/riddle/etc)
                 echo '</p>';
-                echo form::input('captcha_answer');
+                echo form::input('captcha_response');
                 echo form::submit(array('value' => 'Check'));
                 echo form::close();

trunk/system/config/captcha.php

@@ -8 +8 @@
  *
  * Group Options:
- *  style           - Captcha type, e.g. basic, word, math, riddle
+ *  style           - Captcha type, e.g. basic, alpha, word, math, riddle
  *  width           - Width of the Captcha image
  *  height          - Height of the Captcha image
@@ -19 +19 @@
 $config['default'] = array
 (
-        'style'           => 'basic',
+        'style'           => 'alpha',
         'width'           => 150,
         'height'          => 50,

trunk/system/libraries/Captcha.php

@@ -27 +27 @@
 
         // The Captcha challenge answer, the text the user is supposed to enter
-        public static $answer;
+        public static $response;
 
         /**
@@ -121 +121 @@
 
                 // Generate a new Captcha challenge
-                self::$answer = (string) $this->driver->generate_challenge();
+                self::$response = (string) $this->driver->generate_challenge();
 
                 // Store the answer in a session
-                Session::instance()->set('captcha_answer', self::$answer);
+                Session::instance()->set('captcha_response', self::$response);
 
                 Log::add('debug', 'Captcha Library initialized');
@@ -130 +130 @@
 
         /**
-         * Validates a Captcha answer.
+         * Validates a Captcha response.
          *
-         * @param   string   captcha answer
+         * @param   string   captcha response
          * @return  boolean
          */
-        public static function valid($answer)
+        public static function valid($response)
         {
-                return (strtoupper($answer) === strtoupper(Session::instance()->get('captcha_answer')));
+                return (strtoupper($response) === strtoupper(Session::instance()->get('captcha_response')));
         }
 

trunk/system/libraries/drivers/Captcha/Alpha.php

@@ -1 +1 @@
 <?php defined('SYSPATH') or die('No direct script access.');
 /**
- * Captcha driver for "basic" style.
+ * Captcha driver for "alpha" style.
  *
  * $Id$
@@ -39 +39 @@
                 $this->image_gradient($color1, $color2);
 
+                // Add a few random circles
+                for ($i = 0, $count = mt_rand(10, Captcha::$config['complexity'] * 3); $i < $count; $i++)
+                {
+                        $color = imagecolorallocatealpha($this->image, mt_rand(0, 255), mt_rand(0, 255), mt_rand(0, 255), mt_rand(80, 120));
+                        $size = mt_rand(5, Captcha::$config['height'] / 3);
+                        imagefilledellipse($this->image, mt_rand(0, Captcha::$config['width']), mt_rand(0, Captcha::$config['height']), $size, $size, $color);
+                }
+
                 // Calculate character font-size and spacing
-                $default_size = min(Captcha::$config['width'], Captcha::$config['height'] * 2) / strlen(Captcha::$answer);
-                $spacing = (int) (Captcha::$config['width'] * 0.9 / strlen(Captcha::$answer));
+                $default_size = min(Captcha::$config['width'], Captcha::$config['height'] * 2) / strlen(Captcha::$response);
+                $spacing = (int) (Captcha::$config['width'] * 0.9 / strlen(Captcha::$response));
 
                 // Background alphabetic character attributes
@@ -48 +56 @@
 
                 // Draw each Captcha character with varying attributes
-                for ($i = 0, $strlen = strlen(Captcha::$answer); $i < $strlen; $i++)
+                for ($i = 0, $strlen = strlen(Captcha::$response); $i < $strlen; $i++)
                 {
                         $angle = mt_rand(-40, 20);
                         // Scale the character size on image height
                         $size = $default_size / 10 * mt_rand(8, 12);
-                        $box = imageftbbox($size, $angle, Captcha::$config['font'], Captcha::$answer[$i]);
+                        $box = imageftbbox($size, $angle, Captcha::$config['font'], Captcha::$response[$i]);
 
                         // Calculate character starting coordinates
@@ -64 +72 @@
 
                         // Write text character to image
-                        imagefttext($this->image, $size, $angle, $x, $y, $color, Captcha::$config['font'], Captcha::$answer[$i]);
+                        imagefttext($this->image, $size, $angle, $x, $y, $color, Captcha::$config['font'], Captcha::$response[$i]);
 
                         // Draw "ghost" alphabetic character
-                        $text_color = imagecolorallocatealpha($this->image, mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand(60, 120));
-                        $char = substr($chars, mt_rand(0,14), 1);
-                        imagettftext($this->image, $size, ($angle + (mt_rand(5,10))), ($x - (mt_rand(5,10))), ($y + (mt_rand(5,10))), $text_color, Captcha::$config['font'], $char);
-
+                        $text_color = imagecolorallocatealpha($this->image, mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand($color_limit + 8, 255), mt_rand(70, 120));
+                        $char = substr($chars, mt_rand(0, 14), 1);
+                        imagettftext($this->image, $size * 2, mt_rand(-45, 45), ($x - (mt_rand(5, 10))), ($y + (mt_rand(5, 10))), $text_color, Captcha::$config['font'], $char);
                 }
 

trunk/system/libraries/drivers/Captcha/Basic.php

@@ -40 +40 @@
 
                 // Add a few random lines
-                for ($i = 0, $count = mt_rand(5, 10); $i < $count; $i++)
+                for ($i = 0, $count = mt_rand(5, Captcha::$config['complexity'] * 3); $i < $count; $i++)
                 {
-                        $color = imagecolorallocatealpha($this->image, mt_rand(100, 255), mt_rand(100, 255), mt_rand(100, 255), mt_rand(60, 120));
+                        $color = imagecolorallocatealpha($this->image, mt_rand(100, 255), mt_rand(100, 255), mt_rand(100, 255), mt_rand(50, 120));
                         imageline($this->image, mt_rand(0, Captcha::$config['width']), mt_rand(0, Captcha::$config['height']), mt_rand(0, Captcha::$config['width']), mt_rand(0, Captcha::$config['height']), $color);
                 }
 
                 // Calculate character font-size and spacing
-                $default_size = min(Captcha::$config['width'], Captcha::$config['height'] * 2) / (strlen(Captcha::$answer) + 1);
-                $spacing = (int) (Captcha::$config['width'] * 0.9 / strlen(Captcha::$answer));
+                $default_size = min(Captcha::$config['width'], Captcha::$config['height'] * 2) / (strlen(Captcha::$response) + 1);
+                $spacing = (int) (Captcha::$config['width'] * 0.9 / strlen(Captcha::$response));
 
                 // Draw each Captcha character with varying attributes
-                for ($i = 0, $strlen = strlen(Captcha::$answer); $i < $strlen; $i++)
+                for ($i = 0, $strlen = strlen(Captcha::$response); $i < $strlen; $i++)
                 {
                         // Allocate random color, size and rotation attributes to text
@@ -59 +59 @@
                         // Scale the character size on image height
                         $size = $default_size / 10 * mt_rand(8, 12);
-                        $box = imageftbbox($size, $angle, Captcha::$config['font'], Captcha::$answer[$i]);
+                        $box = imageftbbox($size, $angle, Captcha::$config['font'], Captcha::$response[$i]);
 
                         // Calculate character starting coordinates
@@ -66 +66 @@
 
                         // Write text character to image
-                        imagefttext($this->image, $size, $angle, $x, $y, $color, Captcha::$config['font'], Captcha::$answer[$i]);
+                        imagefttext($this->image, $size, $angle, $x, $y, $color, Captcha::$config['font'], Captcha::$response[$i]);
                 }