| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  |  * This is a lightweight proxy for serving images, generally meant to be used alongside SSL | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  |  * Simple Machines Forum (SMF) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  |  * @package SMF | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  |  * @author Simple Machines http://www.simplemachines.org | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  |  * @copyright 2017 Simple Machines and individual contributors | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  |  * @license http://www.simplemachines.org/about/smf/license.php BSD | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  |  * @version 2.1 Beta 4 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  | define('SMF', 'proxy'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |  * Class ProxyServer | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  | class ProxyServer | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  | 	/** @var bool $enabled Whether or not this is enabled */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  | 	protected $enabled; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  | 	/** @var int $maxSize The maximum size for files to cache */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  | 	protected $maxSize; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  | 	/** @var string $secret A secret code used for hashing */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  | 	protected $secret; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  | 	/** @var string The cache directory */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  | 	protected $cache; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 35 |  |  | 	/** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  | 	 * Constructor, loads up the Settings for the proxy | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  | 	 * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  | 	 * @access public | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  | 	 */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  | 	public function __construct() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  | 	{ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  | 		global $image_proxy_enabled, $image_proxy_maxsize, $image_proxy_secret, $cachedir, $sourcedir; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  | 		require_once(dirname(__FILE__) . '/Settings.php'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  | 		require_once($sourcedir . '/Class-CurlFetchWeb.php'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  | 		require_once($sourcedir . '/Subs.php'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  | 		// Turn off all error reporting; any extra junk makes for an invalid image. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  | 		error_reporting(0); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  | 		$this->enabled = (bool) $image_proxy_enabled; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  | 		$this->maxSize = (int) $image_proxy_maxsize; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  | 		$this->secret = (string) $image_proxy_secret; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  | 		$this->cache = $cachedir . '/images'; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  | 	} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  | 	/** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  | 	 * Checks whether the request is valid or not | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  | 	 * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 |  |  | 	 * @access public | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  | 	 * @return bool Whether the request is valid | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  | 	 */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  | 	public function checkRequest() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 |  |  | 	{ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  | 		if (!$this->enabled) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  | 		// Try to create the image cache directory if it doesn't exist | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  | 		if (!file_exists($this->cache)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  | 			if (!mkdir($this->cache) || !copy(dirname($this->cache) . '/index.php', $this->cache . '/index.php')) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  | 				return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  | 		if (empty($_GET['hash']) || empty($_GET['request'])) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  | 		$hash = $_GET['hash']; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  | 		$request = $_GET['request']; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  | 		if (md5($request . $this->secret) != $hash) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  | 		// Attempt to cache the request if it doesn't exist | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  | 		if (!$this->isCached($request)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  | 			return $this->cacheImage($request); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  | 		return true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  | 	} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  | 	/** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  | 	 * Serves the request | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  | 	 * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 |  |  | 	 * @access public | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  | 	 * @return void | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  | 	 */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 |  |  | 	public function serve() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  | 	{ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  | 		$request = $_GET['request']; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 |  |  | 		$cached_file = $this->getCachedPath($request); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  | 		$cached = json_decode(file_get_contents($cached_file), true); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  | 		// Did we get an error when trying to fetch the image | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  | 		$response = $this->checkRequest(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  | 		if (!$response) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  | 			// Throw a 404 | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  | 			header('HTTP/1.0 404 Not Found'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  | 			exit; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  | 		} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 |  |  | 		// Is the cache expired? | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 |  |  | 		if (!$cached || time() - $cached['time'] > (5 * 86400)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  | 		{ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  | 			@unlink($cached_file); | 
                            
                    |  |  |  | 
                                                                                        
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                | 114 |  |  | 			if ($this->checkRequest()) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 |  |  | 				$this->serve(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  | 			redirectexit($request); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 |  |  | 		} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 |  |  | 		// Right, image not cached? Simply redirect, then. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  | 		if (!$response) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  | 		    redirectexit($request); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  | 		// Make sure we're serving an image | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 |  |  | 		$contentParts = explode('/', !empty($cached['content_type']) ? $cached['content_type'] : ''); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  | 		if ($contentParts[0] != 'image') | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  | 			exit; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  | 		header('Content-type: ' . $cached['content_type']); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 |  |  | 		header('Content-length: ' . $cached['size']); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  | 		echo base64_decode($cached['body']); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  | 	} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  | 	/** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 |  |  | 	 * Returns the request's hashed filepath | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 |  |  | 	 * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  | 	 * @access public | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 |  |  | 	 * @param string $request The request to get the path for | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  | 	 * @return string The hashed filepath for the specified request | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 139 |  |  | 	 */ | 
            
                                                                        
                            
            
                                    
            
            
                | 140 |  |  | 	protected function getCachedPath($request) | 
            
                                                                        
                            
            
                                    
            
            
                | 141 |  |  | 	{ | 
            
                                                                        
                            
            
                                    
            
            
                | 142 |  |  | 		return $this->cache . '/' . sha1($request . $this->secret); | 
            
                                                                        
                            
            
                                    
            
            
                | 143 |  |  | 	} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 |  |  | 	/** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 |  |  | 	 * Check whether the image exists in local cache or not | 
            
                                                                                                            
                            
            
                                    
            
            
                | 147 |  |  | 	 * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  | 	 * @access protected | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  | 	 * @param string $request The image to check for in the cache | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  | 	 * @return bool Whether or not the requested image is cached | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  | 	 */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  | 	protected function isCached($request) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 153 |  |  | 	{ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 |  |  | 		return file_exists($this->getCachedPath($request)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 |  |  | 	} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  | 	/** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 |  |  | 	 * Attempts to cache the image while validating it | 
            
                                                                                                            
                            
            
                                    
            
            
                | 159 |  |  | 	 * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  | 	 * @access protected | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  | 	 * @param string $request The image to cache/validate | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  | 	 * @return bool|int Whether the specified image was cached or error code when accessing | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 |  |  | 	 */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  | 	protected function cacheImage($request) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 |  |  | 	{ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 |  |  | 		$dest = $this->getCachedPath($request); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 |  |  | 		$curl = new curl_fetch_web_data(array(CURLOPT_BINARYTRANSFER => 1)); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  | 		$request = $curl->get_url_data($request); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  | 		$responseCode = $request->result('code'); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 |  |  | 		$response = $request->result(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  | 		if (empty($response)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 174 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  | 		if ($responseCode != 200) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  | 		} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  | 		$headers = $response['headers']; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  | 		// Make sure the url is returning an image | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 |  |  | 		$contentParts = explode('/', !empty($headers['content-type']) ? $headers['content-type'] : ''); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  | 		if ($contentParts[0] != 'image') | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 |  |  | 		// Validate the filesize | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 |  |  | 		if ($response['size'] > ($this->maxSize * 1024)) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 189 |  |  | 			return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 190 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 191 |  |  | 		return file_put_contents($dest, json_encode(array( | 
            
                                                                                                            
                            
            
                                    
            
            
                | 192 |  |  | 			'content_type' => $headers['content-type'], | 
            
                                                                                                            
                            
            
                                    
            
            
                | 193 |  |  | 			'size' => $response['size'], | 
            
                                                                                                            
                            
            
                                    
            
            
                | 194 |  |  | 			'time' => time(), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 195 |  |  | 			'body' => base64_encode($response['body']), | 
            
                                                                                                            
                            
            
                                    
            
            
                | 196 |  |  | 		))) === false ? 1 : null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 197 |  |  | 	} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 198 |  |  | } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 199 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 200 |  |  | $proxy = new ProxyServer(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 201 |  |  | $proxy->serve(); | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 202 |  |  |  | 
            
                                                        
            
                                    
            
            
                | 203 |  |  | ?> | 
                            
                    |  |  |  | 
                                                                                        
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