wcfsetup/install/files/lib/util/ImageUtil.class.php

   1 <?php
   2 namespace wcf\util;
   3 use wcf\system\exception\SystemException;
   4 use wcf\system\image\ImageHandler;
   5
   6 /**
   7  * Contains image-related functions.
   8  *
   9  * @author      Marcel Werk
  10  * @copyright   2001-2019 WoltLab GmbH
  11  * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
  12  * @package     WoltLabSuite\Core\Util
  13  */
  14 final class ImageUtil {
  15         /**
  16          * image extensions
  17          * @var array
  18          */
  19         protected static $imageExtensions = ['jpeg', 'jpg', 'png', 'gif'];
  20
  21         /**
  22          * Checks the content of an image for bad sections, e.g. the use of javascript
  23          * and returns false if any bad stuff was found.
  24          *
  25          * @param       string          $file
  26          * @return      boolean
  27          */
  28         public static function checkImageContent($file) {
  29                 // get file content
  30                 $content = file_get_contents($file);
  31
  32                 // remove some characters
  33                 $content = strtolower(preg_replace('/[^a-z0-9<\(]+/i', '', $content));
  34                 $content = str_replace('description', '', $content);
  35
  36                 // search for javascript
  37                 if (strpos($content, 'script') !== false || strpos($content, 'javascript') !== false || strpos($content, 'expression(') !== false) return false;
  38
  39                 return true;
  40         }
  41
  42         /**
  43          * Checks whether a given file is a valid image.
  44          *
  45          * @param       string          $location
  46          * @param       string|null     $filename
  47          * @param       bool            $handleSvgAsValidImage  flag, whether a svg file is handled as image
  48          * @return      bool
  49          */
  50         public static function isImage($location, $filename = null, $handleSvgAsValidImage = false) {
  51                 if ($filename === null) {
  52                         $filename = basename($location);
  53                 }
  54
  55                 if (@getimagesize($location) !== false) {
  56                         $extension = pathinfo($filename, PATHINFO_EXTENSION);
  57
  58                         if (in_array(mb_strtolower($extension), self::$imageExtensions)) {
  59                                 return true;
  60                         }
  61                 }
  62                 else if ($handleSvgAsValidImage) {
  63                         if (in_array(FileUtil::getMimeType($location), ['image/svg', 'image/svg+xml']) && mb_strtolower(pathinfo($filename, PATHINFO_EXTENSION)) === 'svg') {
  64                                 return true;
  65                         }
  66                 }
  67
  68                 return false;
  69         }
  70
  71         /**
  72          * Return the file extension for an image with the given mime type.
  73          *
  74          * @param       string          $mimeType
  75          * @return      string
  76          * @see http://www.php.net/manual/en/function.image-type-to-mime-type.php
  77          */
  78         public static function getExtensionByMimeType($mimeType) {
  79                 switch ($mimeType) {
  80                         case 'image/gif':
  81                                 return 'gif';
  82                         case 'image/jpeg':
  83                                 return 'jpg';
  84                         case 'image/png':
  85                                 return 'png';
  86                         case 'application/x-shockwave-flash':
  87                                 return 'swf';
  88                         case 'image/psd':
  89                                 return 'psd';
  90                         case 'image/bmp':
  91                         case 'image/x-ms-bmp':
  92                                 return 'bmp';
  93                         case 'image/tiff':
  94                                 return 'tiff';
  95                         default:
  96                                 return '';
  97                 }
  98         }
  99
 100         /**
 101          * Enforces dimensions for given image.
 102          *
 103          * @param       string          $filename
 104          * @param       integer         $maxWidth
 105          * @param       integer         $maxHeight
 106          * @param       boolean         $obtainDimensions
 107          * @return      string          new filename if file was changed, otherwise old filename
 108          * @since       5.2
 109          */
 110         public static function enforceDimensions($filename, $maxWidth, $maxHeight, $obtainDimensions = true) {
 111                 $imageData = getimagesize($filename);
 112                 if ($imageData[0] > $maxWidth || $imageData[1] > $maxHeight) {
 113                         $adapter = ImageHandler::getInstance()->getAdapter();
 114                         $adapter->loadFile($filename);
 115                         $filename = FileUtil::getTemporaryFilename();
 116                         $thumbnail = $adapter->createThumbnail($maxWidth, $maxHeight, $obtainDimensions);
 117                         $adapter->writeImage($thumbnail, $filename);
 118                 }
 119
 120                 return $filename;
 121         }
 122
 123         /**
 124          * Rotates the given image based on the orientation stored in the exif data.
 125          *
 126          * @param       string          $filename
 127          * @return      string          new filename if file was changed, otherwise old filename
 128          * @since       5.2
 129          */
 130         public static function fixOrientation($filename) {
 131                 try {
 132                         $exifData = ExifUtil::getExifData($filename);
 133                         if (!empty($exifData)) {
 134                                 $orientation = ExifUtil::getOrientation($exifData);
 135                                 if ($orientation != ExifUtil::ORIENTATION_ORIGINAL) {
 136                                         $adapter = ImageHandler::getInstance()->getAdapter();
 137                                         $adapter->loadFile($filename);
 138
 139                                         $newImage = null;
 140                                         switch ($orientation) {
 141                                                 case ExifUtil::ORIENTATION_180_ROTATE:
 142                                                         $newImage = $adapter->rotate(180);
 143                                                         break;
 144
 145                                                 case ExifUtil::ORIENTATION_90_ROTATE:
 146                                                         $newImage = $adapter->rotate(90);
 147                                                         break;
 148
 149                                                 case ExifUtil::ORIENTATION_270_ROTATE:
 150                                                         $newImage = $adapter->rotate(270);
 151                                                         break;
 152
 153                                                 case ExifUtil::ORIENTATION_HORIZONTAL_FLIP:
 154                                                 case ExifUtil::ORIENTATION_VERTICAL_FLIP:
 155                                                 case ExifUtil::ORIENTATION_VERTICAL_FLIP_270_ROTATE:
 156                                                 case ExifUtil::ORIENTATION_HORIZONTAL_FLIP_270_ROTATE:
 157                                                         // unsupported
 158                                                         break;
 159                                         }
 160
 161                                         if ($newImage !== null) {
 162                                                 if ($newImage instanceof \Imagick) {
 163                                                         $newImage->setImageOrientation(\Imagick::ORIENTATION_TOPLEFT);
 164                                                 }
 165
 166                                                 $adapter->load($newImage, $adapter->getType());
 167                                         }
 168
 169                                         $newFilename = FileUtil::getTemporaryFilename();
 170                                         $adapter->writeImage($newFilename);
 171                                         $filename = $newFilename;
 172                                 }
 173                         }
 174                 }
 175                 catch (SystemException $e) {}
 176
 177                 return $filename;
 178         }
 179
 180         /**
 181          * Forbid creation of ImageUtil objects.
 182          */
 183         private function __construct() {
 184                 // does nothing
 185         }
 186 }