137 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			PHP
		
	
	
		
		
			
		
	
	
			137 lines
		
	
	
		
			4.3 KiB
		
	
	
	
		
			PHP
		
	
	
|  | <?php | ||
|  | 
 | ||
|  | /** | ||
|  |  * Implements data: URI for base64 encoded images supported by GD. | ||
|  |  */ | ||
|  | class HTMLPurifier_URIScheme_data extends HTMLPurifier_URIScheme | ||
|  | { | ||
|  |     /** | ||
|  |      * @type bool | ||
|  |      */ | ||
|  |     public $browsable = true; | ||
|  | 
 | ||
|  |     /** | ||
|  |      * @type array | ||
|  |      */ | ||
|  |     public $allowed_types = array( | ||
|  |         // you better write validation code for other types if you
 | ||
|  |         // decide to allow them
 | ||
|  |         'image/jpeg' => true, | ||
|  |         'image/gif' => true, | ||
|  |         'image/png' => true, | ||
|  |     ); | ||
|  |     // this is actually irrelevant since we only write out the path
 | ||
|  |     // component
 | ||
|  |     /** | ||
|  |      * @type bool | ||
|  |      */ | ||
|  |     public $may_omit_host = true; | ||
|  | 
 | ||
|  |     /** | ||
|  |      * @param HTMLPurifier_URI $uri | ||
|  |      * @param HTMLPurifier_Config $config | ||
|  |      * @param HTMLPurifier_Context $context | ||
|  |      * @return bool | ||
|  |      */ | ||
|  |     public function doValidate(&$uri, $config, $context) | ||
|  |     { | ||
|  |         $result = explode(',', $uri->path, 2); | ||
|  |         $is_base64 = false; | ||
|  |         $charset = null; | ||
|  |         $content_type = null; | ||
|  |         if (count($result) == 2) { | ||
|  |             list($metadata, $data) = $result; | ||
|  |             // do some legwork on the metadata
 | ||
|  |             $metas = explode(';', $metadata); | ||
|  |             while (!empty($metas)) { | ||
|  |                 $cur = array_shift($metas); | ||
|  |                 if ($cur == 'base64') { | ||
|  |                     $is_base64 = true; | ||
|  |                     break; | ||
|  |                 } | ||
|  |                 if (substr($cur, 0, 8) == 'charset=') { | ||
|  |                     // doesn't match if there are arbitrary spaces, but
 | ||
|  |                     // whatever dude
 | ||
|  |                     if ($charset !== null) { | ||
|  |                         continue; | ||
|  |                     } // garbage
 | ||
|  |                     $charset = substr($cur, 8); // not used
 | ||
|  |                 } else { | ||
|  |                     if ($content_type !== null) { | ||
|  |                         continue; | ||
|  |                     } // garbage
 | ||
|  |                     $content_type = $cur; | ||
|  |                 } | ||
|  |             } | ||
|  |         } else { | ||
|  |             $data = $result[0]; | ||
|  |         } | ||
|  |         if ($content_type !== null && empty($this->allowed_types[$content_type])) { | ||
|  |             return false; | ||
|  |         } | ||
|  |         if ($charset !== null) { | ||
|  |             // error; we don't allow plaintext stuff
 | ||
|  |             $charset = null; | ||
|  |         } | ||
|  |         $data = rawurldecode($data); | ||
|  |         if ($is_base64) { | ||
|  |             $raw_data = base64_decode($data); | ||
|  |         } else { | ||
|  |             $raw_data = $data; | ||
|  |         } | ||
|  |         if ( strlen($raw_data) < 12 ) { | ||
|  |             // error; exif_imagetype throws exception with small files,
 | ||
|  |             // and this likely indicates a corrupt URI/failed parse anyway
 | ||
|  |             return false; | ||
|  |         } | ||
|  |         // XXX probably want to refactor this into a general mechanism
 | ||
|  |         // for filtering arbitrary content types
 | ||
|  |         if (function_exists('sys_get_temp_dir')) { | ||
|  |             $file = tempnam(sys_get_temp_dir(), ""); | ||
|  |         } else { | ||
|  |             $file = tempnam("/tmp", ""); | ||
|  |         } | ||
|  |         file_put_contents($file, $raw_data); | ||
|  |         if (function_exists('exif_imagetype')) { | ||
|  |             $image_code = exif_imagetype($file); | ||
|  |             unlink($file); | ||
|  |         } elseif (function_exists('getimagesize')) { | ||
|  |             set_error_handler(array($this, 'muteErrorHandler')); | ||
|  |             $info = getimagesize($file); | ||
|  |             restore_error_handler(); | ||
|  |             unlink($file); | ||
|  |             if ($info == false) { | ||
|  |                 return false; | ||
|  |             } | ||
|  |             $image_code = $info[2]; | ||
|  |         } else { | ||
|  |             trigger_error("could not find exif_imagetype or getimagesize functions", E_USER_ERROR); | ||
|  |         } | ||
|  |         $real_content_type = image_type_to_mime_type($image_code); | ||
|  |         if ($real_content_type != $content_type) { | ||
|  |             // we're nice guys; if the content type is something else we
 | ||
|  |             // support, change it over
 | ||
|  |             if (empty($this->allowed_types[$real_content_type])) { | ||
|  |                 return false; | ||
|  |             } | ||
|  |             $content_type = $real_content_type; | ||
|  |         } | ||
|  |         // ok, it's kosher, rewrite what we need
 | ||
|  |         $uri->userinfo = null; | ||
|  |         $uri->host = null; | ||
|  |         $uri->port = null; | ||
|  |         $uri->fragment = null; | ||
|  |         $uri->query = null; | ||
|  |         $uri->path = "$content_type;base64," . base64_encode($raw_data); | ||
|  |         return true; | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * @param int $errno | ||
|  |      * @param string $errstr | ||
|  |      */ | ||
|  |     public function muteErrorHandler($errno, $errstr) | ||
|  |     { | ||
|  |     } | ||
|  | } |