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<?php/*** CodeIgniter** An open source application development framework for PHP** This content is released under the MIT License (MIT)** Copyright (c) 2014 - 2016, British Columbia Institute of Technology** Permission is hereby granted, free of charge, to any person obtaining a copy* of this software and associated documentation files (the "Software"), to deal* in the Software without restriction, including without limitation the rights* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell* copies of the Software, and to permit persons to whom the Software is* furnished to do so, subject to the following conditions:** The above copyright notice and this permission notice shall be included in* all copies or substantial portions of the Software.** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN* THE SOFTWARE.** @package CodeIgniter* @author EllisLab Dev Team* @copyright Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)* @copyright Copyright (c) 2014 - 2016, British Columbia Institute of Technology (http://bcit.ca/)* @license http://opensource.org/licenses/MIT MIT License* @link https://codeigniter.com* @since Version 1.0.0* @filesource*/defined('BASEPATH') OR exit('No direct script access allowed');/*** CodeIgniter CAPTCHA Helper** @package CodeIgniter* @subpackage Helpers* @category Helpers* @author EllisLab Dev Team* @link https://codeigniter.com/user_guide/helpers/captcha_helper.html*/// ------------------------------------------------------------------------if ( ! function_exists('create_captcha')){/*** Create CAPTCHA** @param array $data data for the CAPTCHA* @param string $img_path path to create the image in* @param string $img_url URL to the CAPTCHA image folder* @param string $font_path server path to font* @return string*/function create_captcha($data = '', $img_path = '', $img_url = '', $font_path = ''){$defaults = array('word' => '','img_path' => '','img_url' => '','img_width' => '150','img_height' => '30','font_path' => '','expiration' => 7200,'word_length' => 8,'font_size' => 16,'img_id' => '','pool' => '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ','colors' => array('background' => array(255,255,255),'border' => array(153,102,102),'text' => array(204,153,153),'grid' => array(255,182,182)));foreach ($defaults as $key => $val){if ( ! is_array($data) && empty($$key)){$$key = $val;}else{$$key = isset($data[$key]) ? $data[$key] : $val;}}if ($img_path === '' OR $img_url === ''OR ! is_dir($img_path) OR ! is_really_writable($img_path)OR ! extension_loaded('gd')){return FALSE;}// -----------------------------------// Remove old images// -----------------------------------$now = microtime(TRUE);$current_dir = @opendir($img_path);while ($filename = @readdir($current_dir)){if (in_array(substr($filename, -4), array('.jpg', '.png'))&& (str_replace(array('.jpg', '.png'), '', $filename) + $expiration) < $now){@unlink($img_path.$filename);}}@closedir($current_dir);// -----------------------------------// Do we have a "word" yet?// -----------------------------------if (empty($word)){$word = '';$pool_length = strlen($pool);$rand_max = $pool_length - 1;// PHP7 or a suitable polyfillif (function_exists('random_int')){try{for ($i = 0; $i < $word_length; $i++){$word .= $pool[random_int(0, $rand_max)];}}catch (Exception $e){// This means fallback to the next possible// alternative to random_int()$word = '';}}}if (empty($word)){// Nobody will have a larger character pool than// 256 characters, but let's handle it just in case ...//// No, I do not care that the fallback to mt_rand() can// handle it; if you trigger this, you're very obviously// trying to break it. -- Narfif ($pool_length > 256){return FALSE;}// We'll try using the operating system's PRNG first,// which we can access through CI_Security::get_random_bytes()$security = get_instance()->security;// To avoid numerous get_random_bytes() calls, we'll// just try fetching as much bytes as we need at once.if (($bytes = $security->get_random_bytes($pool_length)) !== FALSE){$byte_index = $word_index = 0;while ($word_index < $word_length){// Do we have more random data to use?// It could be exhausted by previous iterations// ignoring bytes higher than $rand_max.if ($byte_index === $pool_length){// No failures should be possible if the// first get_random_bytes() call didn't// return FALSE, but still ...for ($i = 0; $i < 5; $i++){if (($bytes = $security->get_random_bytes($pool_length)) === FALSE){continue;}$byte_index = 0;break;}if ($bytes === FALSE){// Sadly, this means fallback to mt_rand()$word = '';break;}}list(, $rand_index) = unpack('C', $bytes[$byte_index++]);if ($rand_index > $rand_max){continue;}$word .= $pool[$rand_index];$word_index++;}}}if (empty($word)){for ($i = 0; $i < $word_length; $i++){$word .= $pool[mt_rand(0, $rand_max)];}}elseif ( ! is_string($word)){$word = (string) $word;}// -----------------------------------// Determine angle and position// -----------------------------------$length = strlen($word);$angle = ($length >= 6) ? mt_rand(-($length-6), ($length-6)) : 0;$x_axis = mt_rand(6, (360/$length)-16);$y_axis = ($angle >= 0) ? mt_rand($img_height, $img_width) : mt_rand(6, $img_height);// Create image// PHP.net recommends imagecreatetruecolor(), but it isn't always available$im = function_exists('imagecreatetruecolor')? imagecreatetruecolor($img_width, $img_height): imagecreate($img_width, $img_height);// -----------------------------------// Assign colors// ----------------------------------is_array($colors) OR $colors = $defaults['colors'];foreach (array_keys($defaults['colors']) as $key){// Check for a possible missing valueis_array($colors[$key]) OR $colors[$key] = $defaults['colors'][$key];$colors[$key] = imagecolorallocate($im, $colors[$key][0], $colors[$key][1], $colors[$key][2]);}// Create the rectangleImageFilledRectangle($im, 0, 0, $img_width, $img_height, $colors['background']);// -----------------------------------// Create the spiral pattern// -----------------------------------$theta = 1;$thetac = 7;$radius = 16;$circles = 20;$points = 32;for ($i = 0, $cp = ($circles * $points) - 1; $i < $cp; $i++){$theta += $thetac;$rad = $radius * ($i / $points);$x = ($rad * cos($theta)) + $x_axis;$y = ($rad * sin($theta)) + $y_axis;$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, $colors['grid']);$theta -= $thetac;}// -----------------------------------// Write the text// -----------------------------------$use_font = ($font_path !== '' && file_exists($font_path) && function_exists('imagettftext'));if ($use_font === FALSE){($font_size > 5) && $font_size = 5;$x = mt_rand(0, $img_width / ($length / 3));$y = 0;}else{($font_size > 30) && $font_size = 30;$x = mt_rand(0, $img_width / ($length / 1.5));$y = $font_size + 2;}for ($i = 0; $i < $length; $i++){if ($use_font === FALSE){$y = mt_rand(0 , $img_height / 2);imagestring($im, $font_size, $x, $y, $word[$i], $colors['text']);$x += ($font_size * 2);}else{$y = mt_rand($img_height / 2, $img_height - 3);imagettftext($im, $font_size, $angle, $x, $y, $colors['text'], $font_path, $word[$i]);$x += $font_size;}}// Create the borderimagerectangle($im, 0, 0, $img_width - 1, $img_height - 1, $colors['border']);// -----------------------------------// Generate the image// -----------------------------------$img_url = rtrim($img_url, '/').'/';if (function_exists('imagejpeg')){$img_filename = $now.'.jpg';imagejpeg($im, $img_path.$img_filename);}elseif (function_exists('imagepng')){$img_filename = $now.'.png';imagepng($im, $img_path.$img_filename);}else{return FALSE;}$img = '<img '.($img_id === '' ? '' : 'id="'.$img_id.'"').' src="'.$img_url.$img_filename.'" style="width: '.$img_width.'; height: '.$img_height .'; border: 0;" alt=" " />';ImageDestroy($im);return array('word' => $word, 'time' => $now, 'image' => $img, 'filename' => $img_filename);}}