/captcha.php
PHP | 133 lines | 58 code | 14 blank | 61 comment | 8 complexity | a6ec0e470a5d9d9acc681b2310f804ba MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.1
- <?php
- /*
- * This file is part of kusaba.
- *
- * kusaba is free software; you can redistribute it and/or modify it under the
- * terms of the GNU General Public License as published by the Free Software
- * Foundation; either version 2 of the License, or (at your option) any later
- * version.
- *
- * kusaba is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
- * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * kusaba; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
- /**
- * Captcha display
- *
- * Generates a random word and stores it in a session variable, which is later used as a verification that the poster is in fact a human
- *
- * @package kusaba
- */
-
- /**
- * Start the session
- */
- session_start();
-
- $preconfig_db_unnecessary = true;
-
- /**
- * Require the configuration file
- */
- require 'config.php';
-
- /*
- * File: CaptchaSecurityImages.php
- * Author: Simon Jarvis
- * Copyright: 2006 Simon Jarvis
- * Date: 03/08/06
- * Updated: 07/02/07
- * Requirements: PHP 4/5 with GD and FreeType libraries
- * Link: http://www.white-hat-web-design.co.uk/articles/php-captcha.php
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details:
- * http://www.gnu.org/licenses/gpl.html
- *
- */
-
- /**
- * Captcha image class
- *
- * @package kusaba
- */
- class CaptchaSecurityImages {
-
- function CaptchaSecurityImages($width='120',$height='40',$characters='6',$font) {
- global $font,$font_ballback;
-
- require_once KU_ROOTDIR . 'inc/classes/randword.class.php';
- $randword_class = new Rand_Word;
-
- $code = $randword_class->rand_word($characters);
-
- /* font size will be 75% of the image height */
- $font_size = $height * 0.85;
- $image = @imagecreate($width, $height) or die('Cannot initialize new GD image stream');
- /* set the colours */
- $background_color = imagecolorallocate($image, 255, 255, 255);
- $text_color = imagecolorallocate($image, 35, 45, 100);
- $noise_color = imagecolorallocate($image, 100, 120, 180);
- /* generate random dots in background */
- if (@imagettfbbox($font_size, 0, $font, $code)) {
- $ttf_supported = true;
- for( $i=0; $i<($width*$height)/3; $i++ ) {
- imagefilledellipse($image, mt_rand(0,$width), mt_rand(0,$height), 1, 1, $noise_color);
- }
- } else {
- $ttf_supported = false;
- for( $i=0; $i<($width*$height)/12; $i++ ) {
- imagefilledellipse($image, mt_rand(0,$width), mt_rand(0,$height), 1, 1, $noise_color);
- }
- }
- /* generate random lines in background */
- if ($ttf_supported) {
- for( $i=0; $i<($width*$height)/150; $i++ ) {
- imageline($image, mt_rand(0,$width), mt_rand(0,$height), mt_rand(0,$width), mt_rand(0,$height), $noise_color);
- }
- }
- if ($ttf_supported) {
- $textbox = imagettfbbox($font_size, 0, $font, $code);
- $x = ($width - $textbox[4])/2;
- $y = ($height - $textbox[5])/2;
- imagettftext($image, $font_size, 0, $x, $y, $text_color, $font, $code);
- } else {
- $x = 4;
- $y = 5;
- imagestring($image, $font_ballback, $x, $y, $code, $text_color);
- }
- /* create textbox and add text*/
- $textbox = imagettfbbox($font_size, 0, $font, $code) or die('Error in imagettfbbox function');
- $x = ($width - $textbox[4])/2;
- $y = ($height - $textbox[5])/2;
- imagettftext($image, $font_size, 0, $x, $y, $text_color, $font, $code) or die('Error in imagettftext function');
- /*output captcha image to browser */
- header('Content-Type: image/jpeg');
- imagejpeg($image);
- imagedestroy($image);
- $_SESSION['security_code'] = $code;
- }
-
- }
-
- $width = 90;
- $height = 30;
- $characters = 6;
-
- $font = KU_ROOTDIR . 'lib/fonts/monofont.ttf';
- $font_fallback = imageloadfont(KU_ROOTDIR . 'lib/fonts/captchafont.gdf');
-
- $captcha = new CaptchaSecurityImages($width,$height,$characters,$font);
-
- ?>