includes/upload/UploadBase.php

   1 <?php
   2 /**
   3  * Base class for the backend of file upload.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Upload
  22  */
  23
  24 /**
  25  * @defgroup Upload Upload related
  26  */
  27
  28 /**
  29  * @ingroup Upload
  30  *
  31  * UploadBase and subclasses are the backend of MediaWiki's file uploads.
  32  * The frontends are formed by ApiUpload and SpecialUpload.
  33  *
  34  * @author Brion Vibber
  35  * @author Bryan Tong Minh
  36  * @author Michael Dale
  37  */
  38 abstract class UploadBase {
  39         protected $mTempPath;
  40         protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
  41         protected $mTitle = false, $mTitleError = 0;
  42         protected $mFilteredName, $mFinalExtension;
  43         protected $mLocalFile, $mFileSize, $mFileProps;
  44         protected $mBlackListedExtensions;
  45         protected $mJavaDetected, $mSVGNSError;
  46
  47         protected static $safeXmlEncodings = array(
  48                 'UTF-8',
  49                 'ISO-8859-1',
  50                 'ISO-8859-2',
  51                 'UTF-16',
  52                 'UTF-32'
  53         );
  54
  55         const SUCCESS = 0;
  56         const OK = 0;
  57         const EMPTY_FILE = 3;
  58         const MIN_LENGTH_PARTNAME = 4;
  59         const ILLEGAL_FILENAME = 5;
  60         const OVERWRITE_EXISTING_FILE = 7; # Not used anymore; handled by verifyTitlePermissions()
  61         const FILETYPE_MISSING = 8;
  62         const FILETYPE_BADTYPE = 9;
  63         const VERIFICATION_ERROR = 10;
  64
  65         # HOOK_ABORTED is the new name of UPLOAD_VERIFICATION_ERROR
  66         const UPLOAD_VERIFICATION_ERROR = 11;
  67         const HOOK_ABORTED = 11;
  68         const FILE_TOO_LARGE = 12;
  69         const WINDOWS_NONASCII_FILENAME = 13;
  70         const FILENAME_TOO_LONG = 14;
  71
  72         const SESSION_STATUS_KEY = 'wsUploadStatusData';
  73
  74         /**
  75          * @param int $error
  76          * @return string
  77          */
  78         public function getVerificationErrorCode( $error ) {
  79                 $code_to_status = array(
  80                         self::EMPTY_FILE => 'empty-file',
  81                         self::FILE_TOO_LARGE => 'file-too-large',
  82                         self::FILETYPE_MISSING => 'filetype-missing',
  83                         self::FILETYPE_BADTYPE => 'filetype-banned',
  84                         self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  85                         self::ILLEGAL_FILENAME => 'illegal-filename',
  86                         self::OVERWRITE_EXISTING_FILE => 'overwrite',
  87                         self::VERIFICATION_ERROR => 'verification-error',
  88                         self::HOOK_ABORTED => 'hookaborted',
  89                         self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
  90                         self::FILENAME_TOO_LONG => 'filename-toolong',
  91                 );
  92                 if ( isset( $code_to_status[$error] ) ) {
  93                         return $code_to_status[$error];
  94                 }
  95
  96                 return 'unknown-error';
  97         }
  98
  99         /**
 100          * Returns true if uploads are enabled.
 101          * Can be override by subclasses.
 102          * @return bool
 103          */
 104         public static function isEnabled() {
 105                 global $wgEnableUploads;
 106
 107                 if ( !$wgEnableUploads ) {
 108                         return false;
 109                 }
 110
 111                 # Check php's file_uploads setting
 112                 return wfIsHHVM() || wfIniGetBool( 'file_uploads' );
 113         }
 114
 115         /**
 116          * Returns true if the user can use this upload module or else a string
 117          * identifying the missing permission.
 118          * Can be overridden by subclasses.
 119          *
 120          * @param User $user
 121          * @return bool|string
 122          */
 123         public static function isAllowed( $user ) {
 124                 foreach ( array( 'upload', 'edit' ) as $permission ) {
 125                         if ( !$user->isAllowed( $permission ) ) {
 126                                 return $permission;
 127                         }
 128                 }
 129
 130                 return true;
 131         }
 132
 133         // Upload handlers. Should probably just be a global.
 134         private static $uploadHandlers = array( 'Stash', 'File', 'Url' );
 135
 136         /**
 137          * Create a form of UploadBase depending on wpSourceType and initializes it
 138          *
 139          * @param WebRequest $request
 140          * @param string|null $type
 141          * @return null|UploadBase
 142          */
 143         public static function createFromRequest( &$request, $type = null ) {
 144                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 145
 146                 if ( !$type ) {
 147                         return null;
 148                 }
 149
 150                 // Get the upload class
 151                 $type = ucfirst( $type );
 152
 153                 // Give hooks the chance to handle this request
 154                 $className = null;
 155                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 156                 if ( is_null( $className ) ) {
 157                         $className = 'UploadFrom' . $type;
 158                         wfDebug( __METHOD__ . ": class name: $className\n" );
 159                         if ( !in_array( $type, self::$uploadHandlers ) ) {
 160                                 return null;
 161                         }
 162                 }
 163
 164                 // Check whether this upload class is enabled
 165                 if ( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 166                         return null;
 167                 }
 168
 169                 // Check whether the request is valid
 170                 if ( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 171                         return null;
 172                 }
 173
 174                 /** @var UploadBase $handler */
 175                 $handler = new $className;
 176
 177                 $handler->initializeFromRequest( $request );
 178
 179                 return $handler;
 180         }
 181
 182         /**
 183          * Check whether a request if valid for this handler
 184          * @param WebRequest $request
 185          * @return bool
 186          */
 187         public static function isValidRequest( $request ) {
 188                 return false;
 189         }
 190
 191         public function __construct() {
 192         }
 193
 194         /**
 195          * Returns the upload type. Should be overridden by child classes
 196          *
 197          * @since 1.18
 198          * @return string
 199          */
 200         public function getSourceType() {
 201                 return null;
 202         }
 203
 204         /**
 205          * Initialize the path information
 206          * @param string $name The desired destination name
 207          * @param string $tempPath The temporary path
 208          * @param int $fileSize The file size
 209          * @param bool $removeTempFile (false) remove the temporary file?
 210          * @throws MWException
 211          */
 212         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 213                 $this->mDesiredDestName = $name;
 214                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 215                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 216                 }
 217                 $this->mTempPath = $tempPath;
 218                 $this->mFileSize = $fileSize;
 219                 $this->mRemoveTempFile = $removeTempFile;
 220         }
 221
 222         /**
 223          * Initialize from a WebRequest. Override this in a subclass.
 224          *
 225          * @param WebRequest $request
 226          */
 227         abstract public function initializeFromRequest( &$request );
 228
 229         /**
 230          * Fetch the file. Usually a no-op
 231          * @return Status
 232          */
 233         public function fetchFile() {
 234                 return Status::newGood();
 235         }
 236
 237         /**
 238          * Return true if the file is empty
 239          * @return bool
 240          */
 241         public function isEmptyFile() {
 242                 return empty( $this->mFileSize );
 243         }
 244
 245         /**
 246          * Return the file size
 247          * @return int
 248          */
 249         public function getFileSize() {
 250                 return $this->mFileSize;
 251         }
 252
 253         /**
 254          * Get the base 36 SHA1 of the file
 255          * @return string
 256          */
 257         public function getTempFileSha1Base36() {
 258                 return FSFile::getSha1Base36FromPath( $this->mTempPath );
 259         }
 260
 261         /**
 262          * @param string $srcPath The source path
 263          * @return string|bool The real path if it was a virtual URL Returns false on failure
 264          */
 265         function getRealPath( $srcPath ) {
 266                 wfProfileIn( __METHOD__ );
 267                 $repo = RepoGroup::singleton()->getLocalRepo();
 268                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 269                         /** @todo Just make uploads work with storage paths UploadFromStash
 270                          *  loads files via virtual URLs.
 271                          */
 272                         $tmpFile = $repo->getLocalCopy( $srcPath );
 273                         if ( $tmpFile ) {
 274                                 $tmpFile->bind( $this ); // keep alive with $this
 275                         }
 276                         $path = $tmpFile ? $tmpFile->getPath() : false;
 277                 } else {
 278                         $path = $srcPath;
 279                 }
 280                 wfProfileOut( __METHOD__ );
 281
 282                 return $path;
 283         }
 284
 285         /**
 286          * Verify whether the upload is sane.
 287          * @return mixed Const self::OK or else an array with error information
 288          */
 289         public function verifyUpload() {
 290                 wfProfileIn( __METHOD__ );
 291
 292                 /**
 293                  * If there was no filename or a zero size given, give up quick.
 294                  */
 295                 if ( $this->isEmptyFile() ) {
 296                         wfProfileOut( __METHOD__ );
 297
 298                         return array( 'status' => self::EMPTY_FILE );
 299                 }
 300
 301                 /**
 302                  * Honor $wgMaxUploadSize
 303                  */
 304                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 305                 if ( $this->mFileSize > $maxSize ) {
 306                         wfProfileOut( __METHOD__ );
 307
 308                         return array(
 309                                 'status' => self::FILE_TOO_LARGE,
 310                                 'max' => $maxSize,
 311                         );
 312                 }
 313
 314                 /**
 315                  * Look at the contents of the file; if we can recognize the
 316                  * type but it's corrupt or data of the wrong type, we should
 317                  * probably not accept it.
 318                  */
 319                 $verification = $this->verifyFile();
 320                 if ( $verification !== true ) {
 321                         wfProfileOut( __METHOD__ );
 322
 323                         return array(
 324                                 'status' => self::VERIFICATION_ERROR,
 325                                 'details' => $verification
 326                         );
 327                 }
 328
 329                 /**
 330                  * Make sure this file can be created
 331                  */
 332                 $result = $this->validateName();
 333                 if ( $result !== true ) {
 334                         wfProfileOut( __METHOD__ );
 335
 336                         return $result;
 337                 }
 338
 339                 $error = '';
 340                 if ( !wfRunHooks( 'UploadVerification',
 341                         array( $this->mDestName, $this->mTempPath, &$error ) )
 342                 ) {
 343                         wfProfileOut( __METHOD__ );
 344
 345                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 346                 }
 347
 348                 wfProfileOut( __METHOD__ );
 349
 350                 return array( 'status' => self::OK );
 351         }
 352
 353         /**
 354          * Verify that the name is valid and, if necessary, that we can overwrite
 355          *
 356          * @return mixed True if valid, otherwise and array with 'status'
 357          * and other keys
 358          */
 359         public function validateName() {
 360                 $nt = $this->getTitle();
 361                 if ( is_null( $nt ) ) {
 362                         $result = array( 'status' => $this->mTitleError );
 363                         if ( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 364                                 $result['filtered'] = $this->mFilteredName;
 365                         }
 366                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 367                                 $result['finalExt'] = $this->mFinalExtension;
 368                                 if ( count( $this->mBlackListedExtensions ) ) {
 369                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 370                                 }
 371                         }
 372
 373                         return $result;
 374                 }
 375                 $this->mDestName = $this->getLocalFile()->getName();
 376
 377                 return true;
 378         }
 379
 380         /**
 381          * Verify the MIME type.
 382          *
 383          * @note Only checks that it is not an evil MIME. The "does it have
 384          *  correct extension given its MIME type?" check is in verifyFile.
 385          *  in `verifyFile()` that MIME type and file extension correlate.
 386          * @param string $mime Representing the MIME
 387          * @return mixed True if the file is verified, an array otherwise
 388          */
 389         protected function verifyMimeType( $mime ) {
 390                 global $wgVerifyMimeType;
 391                 wfProfileIn( __METHOD__ );
 392                 if ( $wgVerifyMimeType ) {
 393                         wfDebug( "mime: <$mime> extension: <{$this->mFinalExtension}>\n" );
 394                         global $wgMimeTypeBlacklist;
 395                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 396                                 wfProfileOut( __METHOD__ );
 397
 398                                 return array( 'filetype-badmime', $mime );
 399                         }
 400
 401                         # Check what Internet Explorer would detect
 402                         $fp = fopen( $this->mTempPath, 'rb' );
 403                         $chunk = fread( $fp, 256 );
 404                         fclose( $fp );
 405
 406                         $magic = MimeMagic::singleton();
 407                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 408                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 409                         foreach ( $ieTypes as $ieType ) {
 410                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 411                                         wfProfileOut( __METHOD__ );
 412
 413                                         return array( 'filetype-bad-ie-mime', $ieType );
 414                                 }
 415                         }
 416                 }
 417
 418                 wfProfileOut( __METHOD__ );
 419
 420                 return true;
 421         }
 422
 423         /**
 424          * Verifies that it's ok to include the uploaded file
 425          *
 426          * @return mixed True of the file is verified, array otherwise.
 427          */
 428         protected function verifyFile() {
 429                 global $wgVerifyMimeType;
 430                 wfProfileIn( __METHOD__ );
 431
 432                 $status = $this->verifyPartialFile();
 433                 if ( $status !== true ) {
 434                         wfProfileOut( __METHOD__ );
 435
 436                         return $status;
 437                 }
 438
 439                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 440                 $mime = $this->mFileProps['mime'];
 441
 442                 if ( $wgVerifyMimeType ) {
 443                         # XXX: Missing extension will be caught by validateName() via getTitle()
 444                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 445                                 wfProfileOut( __METHOD__ );
 446
 447                                 return array( 'filetype-mime-mismatch', $this->mFinalExtension, $mime );
 448                         }
 449                 }
 450
 451                 $handler = MediaHandler::getHandler( $mime );
 452                 if ( $handler ) {
 453                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 454                         if ( !$handlerStatus->isOK() ) {
 455                                 $errors = $handlerStatus->getErrorsArray();
 456                                 wfProfileOut( __METHOD__ );
 457
 458                                 return reset( $errors );
 459                         }
 460                 }
 461
 462                 wfRunHooks( 'UploadVerifyFile', array( $this, $mime, &$status ) );
 463                 if ( $status !== true ) {
 464                         wfProfileOut( __METHOD__ );
 465
 466                         return $status;
 467                 }
 468
 469                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 470                 wfProfileOut( __METHOD__ );
 471
 472                 return true;
 473         }
 474
 475         /**
 476          * A verification routine suitable for partial files
 477          *
 478          * Runs the blacklist checks, but not any checks that may
 479          * assume the entire file is present.
 480          *
 481          * @return mixed True for valid or array with error message key.
 482          */
 483         protected function verifyPartialFile() {
 484                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 485                 wfProfileIn( __METHOD__ );
 486
 487                 # getTitle() sets some internal parameters like $this->mFinalExtension
 488                 $this->getTitle();
 489
 490                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 491
 492                 # check MIME type, if desired
 493                 $mime = $this->mFileProps['file-mime'];
 494                 $status = $this->verifyMimeType( $mime );
 495                 if ( $status !== true ) {
 496                         wfProfileOut( __METHOD__ );
 497
 498                         return $status;
 499                 }
 500
 501                 # check for htmlish code and javascript
 502                 if ( !$wgDisableUploadScriptChecks ) {
 503                         if ( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 504                                 wfProfileOut( __METHOD__ );
 505
 506                                 return array( 'uploadscripted' );
 507                         }
 508                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 509                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath );
 510                                 if ( $svgStatus !== false ) {
 511                                         wfProfileOut( __METHOD__ );
 512
 513                                         return $svgStatus;
 514                                 }
 515                         }
 516                 }
 517
 518                 # Check for Java applets, which if uploaded can bypass cross-site
 519                 # restrictions.
 520                 if ( !$wgAllowJavaUploads ) {
 521                         $this->mJavaDetected = false;
 522                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 523                                 array( $this, 'zipEntryCallback' ) );
 524                         if ( !$zipStatus->isOK() ) {
 525                                 $errors = $zipStatus->getErrorsArray();
 526                                 $error = reset( $errors );
 527                                 if ( $error[0] !== 'zip-wrong-format' ) {
 528                                         wfProfileOut( __METHOD__ );
 529
 530                                         return $error;
 531                                 }
 532                         }
 533                         if ( $this->mJavaDetected ) {
 534                                 wfProfileOut( __METHOD__ );
 535
 536                                 return array( 'uploadjava' );
 537                         }
 538                 }
 539
 540                 # Scan the uploaded file for viruses
 541                 $virus = $this->detectVirus( $this->mTempPath );
 542                 if ( $virus ) {
 543                         wfProfileOut( __METHOD__ );
 544
 545                         return array( 'uploadvirus', $virus );
 546                 }
 547
 548                 wfProfileOut( __METHOD__ );
 549
 550                 return true;
 551         }
 552
 553         /**
 554          * Callback for ZipDirectoryReader to detect Java class files.
 555          *
 556          * @param array $entry
 557          */
 558         function zipEntryCallback( $entry ) {
 559                 $names = array( $entry['name'] );
 560
 561                 // If there is a null character, cut off the name at it, because JDK's
 562                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 563                 // were constructed which had ".class\0" followed by a string chosen to
 564                 // make the hash collide with the truncated name, that file could be
 565                 // returned in response to a request for the .class file.
 566                 $nullPos = strpos( $entry['name'], "\000" );
 567                 if ( $nullPos !== false ) {
 568                         $names[] = substr( $entry['name'], 0, $nullPos );
 569                 }
 570
 571                 // If there is a trailing slash in the file name, we have to strip it,
 572                 // because that's what ZIP_GetEntry() does.
 573                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 574                         $this->mJavaDetected = true;
 575                 }
 576         }
 577
 578         /**
 579          * Alias for verifyTitlePermissions. The function was originally
 580          * 'verifyPermissions', but that suggests it's checking the user, when it's
 581          * really checking the title + user combination.
 582          *
 583          * @param User $user User object to verify the permissions against
 584          * @return mixed An array as returned by getUserPermissionsErrors or true
 585          *   in case the user has proper permissions.
 586          */
 587         public function verifyPermissions( $user ) {
 588                 return $this->verifyTitlePermissions( $user );
 589         }
 590
 591         /**
 592          * Check whether the user can edit, upload and create the image. This
 593          * checks only against the current title; if it returns errors, it may
 594          * very well be that another title will not give errors. Therefore
 595          * isAllowed() should be called as well for generic is-user-blocked or
 596          * can-user-upload checking.
 597          *
 598          * @param User $user User object to verify the permissions against
 599          * @return mixed An array as returned by getUserPermissionsErrors or true
 600          *   in case the user has proper permissions.
 601          */
 602         public function verifyTitlePermissions( $user ) {
 603                 /**
 604                  * If the image is protected, non-sysop users won't be able
 605                  * to modify it by uploading a new revision.
 606                  */
 607                 $nt = $this->getTitle();
 608                 if ( is_null( $nt ) ) {
 609                         return true;
 610                 }
 611                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 612                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 613                 if ( !$nt->exists() ) {
 614                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 615                 } else {
 616                         $permErrorsCreate = array();
 617                 }
 618                 if ( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 619                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 620                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 621
 622                         return $permErrors;
 623                 }
 624
 625                 $overwriteError = $this->checkOverwrite( $user );
 626                 if ( $overwriteError !== true ) {
 627                         return array( $overwriteError );
 628                 }
 629
 630                 return true;
 631         }
 632
 633         /**
 634          * Check for non fatal problems with the file.
 635          *
 636          * This should not assume that mTempPath is set.
 637          *
 638          * @return array Array of warnings
 639          */
 640         public function checkWarnings() {
 641                 global $wgLang;
 642                 wfProfileIn( __METHOD__ );
 643
 644                 $warnings = array();
 645
 646                 $localFile = $this->getLocalFile();
 647                 $filename = $localFile->getName();
 648
 649                 /**
 650                  * Check whether the resulting filename is different from the desired one,
 651                  * but ignore things like ucfirst() and spaces/underscore things
 652                  */
 653                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 654                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 655
 656                 if ( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 657                         $warnings['badfilename'] = $filename;
 658                         // Debugging for bug 62241
 659                         wfDebugLog( 'upload', "Filename: '$filename', mDesiredDestName: "
 660                                 . "'$this->mDesiredDestName', comparableName: '$comparableName'" );
 661                 }
 662
 663                 // Check whether the file extension is on the unwanted list
 664                 global $wgCheckFileExtensions, $wgFileExtensions;
 665                 if ( $wgCheckFileExtensions ) {
 666                         $extensions = array_unique( $wgFileExtensions );
 667                         if ( !$this->checkFileExtension( $this->mFinalExtension, $extensions ) ) {
 668                                 $warnings['filetype-unwanted-type'] = array( $this->mFinalExtension,
 669                                         $wgLang->commaList( $extensions ), count( $extensions ) );
 670                         }
 671                 }
 672
 673                 global $wgUploadSizeWarning;
 674                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 675                         $warnings['large-file'] = array( $wgUploadSizeWarning, $this->mFileSize );
 676                 }
 677
 678                 if ( $this->mFileSize == 0 ) {
 679                         $warnings['emptyfile'] = true;
 680                 }
 681
 682                 $exists = self::getExistsWarning( $localFile );
 683                 if ( $exists !== false ) {
 684                         $warnings['exists'] = $exists;
 685                 }
 686
 687                 // Check dupes against existing files
 688                 $hash = $this->getTempFileSha1Base36();
 689                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 690                 $title = $this->getTitle();
 691                 // Remove all matches against self
 692                 foreach ( $dupes as $key => $dupe ) {
 693                         if ( $title->equals( $dupe->getTitle() ) ) {
 694                                 unset( $dupes[$key] );
 695                         }
 696                 }
 697                 if ( $dupes ) {
 698                         $warnings['duplicate'] = $dupes;
 699                 }
 700
 701                 // Check dupes against archives
 702                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 703                 if ( $archivedImage->getID() > 0 ) {
 704                         if ( $archivedImage->userCan( File::DELETED_FILE ) ) {
 705                                 $warnings['duplicate-archive'] = $archivedImage->getName();
 706                         } else {
 707                                 $warnings['duplicate-archive'] = '';
 708                         }
 709                 }
 710
 711                 wfProfileOut( __METHOD__ );
 712
 713                 return $warnings;
 714         }
 715
 716         /**
 717          * Really perform the upload. Stores the file in the local repo, watches
 718          * if necessary and runs the UploadComplete hook.
 719          *
 720          * @param string $comment
 721          * @param string $pageText
 722          * @param bool $watch
 723          * @param User $user
 724          *
 725          * @return Status Indicating the whether the upload succeeded.
 726          */
 727         public function performUpload( $comment, $pageText, $watch, $user ) {
 728                 wfProfileIn( __METHOD__ );
 729
 730                 $status = $this->getLocalFile()->upload(
 731                         $this->mTempPath,
 732                         $comment,
 733                         $pageText,
 734                         File::DELETE_SOURCE,
 735                         $this->mFileProps,
 736                         false,
 737                         $user
 738                 );
 739
 740                 if ( $status->isGood() ) {
 741                         if ( $watch ) {
 742                                 WatchAction::doWatch(
 743                                         $this->getLocalFile()->getTitle(),
 744                                         $user,
 745                                         WatchedItem::IGNORE_USER_RIGHTS
 746                                 );
 747                         }
 748                         wfRunHooks( 'UploadComplete', array( &$this ) );
 749
 750                         $this->postProcessUpload();
 751                 }
 752
 753                 wfProfileOut( __METHOD__ );
 754
 755                 return $status;
 756         }
 757
 758         /**
 759          * Perform extra steps after a successful upload.
 760          */
 761         public function postProcessUpload() {
 762                 global $wgUploadThumbnailRenderMap;
 763
 764                 $jobs = array();
 765
 766                 $sizes = $wgUploadThumbnailRenderMap;
 767                 rsort( $sizes );
 768
 769                 foreach ( $sizes as $size ) {
 770                         $jobs []= new ThumbnailRenderJob( $this->getLocalFile()->getTitle(), array(
 771                                 'transformParams' => array( 'width' => $size ),
 772                         ) );
 773                 }
 774
 775                 JobQueueGroup::singleton()->push( $jobs );
 776         }
 777
 778         /**
 779          * Returns the title of the file to be uploaded. Sets mTitleError in case
 780          * the name was illegal.
 781          *
 782          * @return Title The title of the file or null in case the name was illegal
 783          */
 784         public function getTitle() {
 785                 if ( $this->mTitle !== false ) {
 786                         return $this->mTitle;
 787                 }
 788                 /* Assume that if a user specified File:Something.jpg, this is an error
 789                  * and that the namespace prefix needs to be stripped of.
 790                  */
 791                 $title = Title::newFromText( $this->mDesiredDestName );
 792                 if ( $title && $title->getNamespace() == NS_FILE ) {
 793                         $this->mFilteredName = $title->getDBkey();
 794                 } else {
 795                         $this->mFilteredName = $this->mDesiredDestName;
 796                 }
 797
 798                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 799                 # exclamation mark, so restrict file name to 240 bytes.
 800                 if ( strlen( $this->mFilteredName ) > 240 ) {
 801                         $this->mTitleError = self::FILENAME_TOO_LONG;
 802                         $this->mTitle = null;
 803
 804                         return $this->mTitle;
 805                 }
 806
 807                 /**
 808                  * Chop off any directories in the given filename. Then
 809                  * filter out illegal characters, and try to make a legible name
 810                  * out of it. We'll strip some silently that Title would die on.
 811                  */
 812                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 813                 /* Normalize to title form before we do any further processing */
 814                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 815                 if ( is_null( $nt ) ) {
 816                         $this->mTitleError = self::ILLEGAL_FILENAME;
 817                         $this->mTitle = null;
 818
 819                         return $this->mTitle;
 820                 }
 821                 $this->mFilteredName = $nt->getDBkey();
 822
 823                 /**
 824                  * We'll want to blacklist against *any* 'extension', and use
 825                  * only the final one for the whitelist.
 826                  */
 827                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 828
 829                 if ( count( $ext ) ) {
 830                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 831                 } else {
 832                         $this->mFinalExtension = '';
 833
 834                         # No extension, try guessing one
 835                         $magic = MimeMagic::singleton();
 836                         $mime = $magic->guessMimeType( $this->mTempPath );
 837                         if ( $mime !== 'unknown/unknown' ) {
 838                                 # Get a space separated list of extensions
 839                                 $extList = $magic->getExtensionsForType( $mime );
 840                                 if ( $extList ) {
 841                                         # Set the extension to the canonical extension
 842                                         $this->mFinalExtension = strtok( $extList, ' ' );
 843
 844                                         # Fix up the other variables
 845                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 846                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 847                                         $ext = array( $this->mFinalExtension );
 848                                 }
 849                         }
 850                 }
 851
 852                 /* Don't allow users to override the blacklist (check file extension) */
 853                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 854                 global $wgFileExtensions, $wgFileBlacklist;
 855
 856                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 857
 858                 if ( $this->mFinalExtension == '' ) {
 859                         $this->mTitleError = self::FILETYPE_MISSING;
 860                         $this->mTitle = null;
 861
 862                         return $this->mTitle;
 863                 } elseif ( $blackListedExtensions ||
 864                         ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 865                                 !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) )
 866                 ) {
 867                         $this->mBlackListedExtensions = $blackListedExtensions;
 868                         $this->mTitleError = self::FILETYPE_BADTYPE;
 869                         $this->mTitle = null;
 870
 871                         return $this->mTitle;
 872                 }
 873
 874                 // Windows may be broken with special characters, see bug 1780
 875                 if ( !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() )
 876                         && !RepoGroup::singleton()->getLocalRepo()->backendSupportsUnicodePaths()
 877                 ) {
 878                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
 879                         $this->mTitle = null;
 880
 881                         return $this->mTitle;
 882                 }
 883
 884                 # If there was more than one "extension", reassemble the base
 885                 # filename to prevent bogus complaints about length
 886                 if ( count( $ext ) > 1 ) {
 887                         $iterations = count( $ext ) - 1;
 888                         for ( $i = 0; $i < $iterations; $i++ ) {
 889                                 $partname .= '.' . $ext[$i];
 890                         }
 891                 }
 892
 893                 if ( strlen( $partname ) < 1 ) {
 894                         $this->mTitleError = self::MIN_LENGTH_PARTNAME;
 895                         $this->mTitle = null;
 896
 897                         return $this->mTitle;
 898                 }
 899
 900                 $this->mTitle = $nt;
 901
 902                 return $this->mTitle;
 903         }
 904
 905         /**
 906          * Return the local file and initializes if necessary.
 907          *
 908          * @return LocalFile|UploadStashFile|null
 909          */
 910         public function getLocalFile() {
 911                 if ( is_null( $this->mLocalFile ) ) {
 912                         $nt = $this->getTitle();
 913                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 914                 }
 915
 916                 return $this->mLocalFile;
 917         }
 918
 919         /**
 920          * If the user does not supply all necessary information in the first upload
 921          * form submission (either by accident or by design) then we may want to
 922          * stash the file temporarily, get more information, and publish the file
 923          * later.
 924          *
 925          * This method will stash a file in a temporary directory for later
 926          * processing, and save the necessary descriptive info into the database.
 927          * This method returns the file object, which also has a 'fileKey' property
 928          * which can be passed through a form or API request to find this stashed
 929          * file again.
 930          *
 931          * @param User $user
 932          * @return UploadStashFile Stashed file
 933          */
 934         public function stashFile( User $user = null ) {
 935                 // was stashSessionFile
 936                 wfProfileIn( __METHOD__ );
 937
 938                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $user );
 939                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
 940                 $this->mLocalFile = $file;
 941
 942                 wfProfileOut( __METHOD__ );
 943
 944                 return $file;
 945         }
 946
 947         /**
 948          * Stash a file in a temporary directory, returning a key which can be used
 949          * to find the file again. See stashFile().
 950          *
 951          * @return string File key
 952          */
 953         public function stashFileGetKey() {
 954                 return $this->stashFile()->getFileKey();
 955         }
 956
 957         /**
 958          * alias for stashFileGetKey, for backwards compatibility
 959          *
 960          * @return string File key
 961          */
 962         public function stashSession() {
 963                 return $this->stashFileGetKey();
 964         }
 965
 966         /**
 967          * If we've modified the upload file we need to manually remove it
 968          * on exit to clean up.
 969          */
 970         public function cleanupTempFile() {
 971                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 972                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 973                         unlink( $this->mTempPath );
 974                 }
 975         }
 976
 977         public function getTempPath() {
 978                 return $this->mTempPath;
 979         }
 980
 981         /**
 982          * Split a file into a base name and all dot-delimited 'extensions'
 983          * on the end. Some web server configurations will fall back to
 984          * earlier pseudo-'extensions' to determine type and execute
 985          * scripts, so the blacklist needs to check them all.
 986          *
 987          * @param string $filename
 988          * @return array
 989          */
 990         public static function splitExtensions( $filename ) {
 991                 $bits = explode( '.', $filename );
 992                 $basename = array_shift( $bits );
 993
 994                 return array( $basename, $bits );
 995         }
 996
 997         /**
 998          * Perform case-insensitive match against a list of file extensions.
 999          * Returns true if the extension is in the list.
1000          *
1001          * @param string $ext
1002          * @param array $list
1003          * @return bool
1004          */
1005         public static function checkFileExtension( $ext, $list ) {
1006                 return in_array( strtolower( $ext ), $list );
1007         }
1008
1009         /**
1010          * Perform case-insensitive match against a list of file extensions.
1011          * Returns an array of matching extensions.
1012          *
1013          * @param array $ext
1014          * @param array $list
1015          * @return bool
1016          */
1017         public static function checkFileExtensionList( $ext, $list ) {
1018                 return array_intersect( array_map( 'strtolower', $ext ), $list );
1019         }
1020
1021         /**
1022          * Checks if the MIME type of the uploaded file matches the file extension.
1023          *
1024          * @param string $mime The MIME type of the uploaded file
1025          * @param string $extension The filename extension that the file is to be served with
1026          * @return bool
1027          */
1028         public static function verifyExtension( $mime, $extension ) {
1029                 $magic = MimeMagic::singleton();
1030
1031                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' ) {
1032                         if ( !$magic->isRecognizableExtension( $extension ) ) {
1033                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
1034                                         "unrecognized extension '$extension', can't verify\n" );
1035
1036                                 return true;
1037                         } else {
1038                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; " .
1039                                         "recognized extension '$extension', so probably invalid file\n" );
1040
1041                                 return false;
1042                         }
1043                 }
1044
1045                 $match = $magic->isMatchingExtension( $extension, $mime );
1046
1047                 if ( $match === null ) {
1048                         if ( $magic->getTypesForExtension( $extension ) !== null ) {
1049                                 wfDebug( __METHOD__ . ": No extension known for $mime, but we know a mime for $extension\n" );
1050
1051                                 return false;
1052                         } else {
1053                                 wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
1054
1055                                 return true;
1056                         }
1057                 } elseif ( $match === true ) {
1058                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
1059
1060                         /** @todo If it's a bitmap, make sure PHP or ImageMagick resp. can handle it! */
1061                         return true;
1062                 } else {
1063                         wfDebug( __METHOD__
1064                                 . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
1065
1066                         return false;
1067                 }
1068         }
1069
1070         /**
1071          * Heuristic for detecting files that *could* contain JavaScript instructions or
1072          * things that may look like HTML to a browser and are thus
1073          * potentially harmful. The present implementation will produce false
1074          * positives in some situations.
1075          *
1076          * @param string $file Pathname to the temporary upload file
1077          * @param string $mime The MIME type of the file
1078          * @param string $extension The extension of the file
1079          * @return bool True if the file contains something looking like embedded scripts
1080          */
1081         public static function detectScript( $file, $mime, $extension ) {
1082                 global $wgAllowTitlesInSVG;
1083                 wfProfileIn( __METHOD__ );
1084
1085                 # ugly hack: for text files, always look at the entire file.
1086                 # For binary field, just check the first K.
1087
1088                 if ( strpos( $mime, 'text/' ) === 0 ) {
1089                         $chunk = file_get_contents( $file );
1090                 } else {
1091                         $fp = fopen( $file, 'rb' );
1092                         $chunk = fread( $fp, 1024 );
1093                         fclose( $fp );
1094                 }
1095
1096                 $chunk = strtolower( $chunk );
1097
1098                 if ( !$chunk ) {
1099                         wfProfileOut( __METHOD__ );
1100
1101                         return false;
1102                 }
1103
1104                 # decode from UTF-16 if needed (could be used for obfuscation).
1105                 if ( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
1106                         $enc = 'UTF-16BE';
1107                 } elseif ( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
1108                         $enc = 'UTF-16LE';
1109                 } else {
1110                         $enc = null;
1111                 }
1112
1113                 if ( $enc ) {
1114                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
1115                 }
1116
1117                 $chunk = trim( $chunk );
1118
1119                 /** @todo FIXME: Convert from UTF-16 if necessary! */
1120                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
1121
1122                 # check for HTML doctype
1123                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
1124                         wfProfileOut( __METHOD__ );
1125
1126                         return true;
1127                 }
1128
1129                 // Some browsers will interpret obscure xml encodings as UTF-8, while
1130                 // PHP/expat will interpret the given encoding in the xml declaration (bug 47304)
1131                 if ( $extension == 'svg' || strpos( $mime, 'image/svg' ) === 0 ) {
1132                         if ( self::checkXMLEncodingMissmatch( $file ) ) {
1133                                 wfProfileOut( __METHOD__ );
1134
1135                                 return true;
1136                         }
1137                 }
1138
1139                 /**
1140                  * Internet Explorer for Windows performs some really stupid file type
1141                  * autodetection which can cause it to interpret valid image files as HTML
1142                  * and potentially execute JavaScript, creating a cross-site scripting
1143                  * attack vectors.
1144                  *
1145                  * Apple's Safari browser also performs some unsafe file type autodetection
1146                  * which can cause legitimate files to be interpreted as HTML if the
1147                  * web server is not correctly configured to send the right content-type
1148                  * (or if you're really uploading plain text and octet streams!)
1149                  *
1150                  * Returns true if IE is likely to mistake the given file for HTML.
1151                  * Also returns true if Safari would mistake the given file for HTML
1152                  * when served with a generic content-type.
1153                  */
1154                 $tags = array(
1155                         '<a href',
1156                         '<body',
1157                         '<head',
1158                         '<html', #also in safari
1159                         '<img',
1160                         '<pre',
1161                         '<script', #also in safari
1162                         '<table'
1163                 );
1164
1165                 if ( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
1166                         $tags[] = '<title';
1167                 }
1168
1169                 foreach ( $tags as $tag ) {
1170                         if ( false !== strpos( $chunk, $tag ) ) {
1171                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1172                                 wfProfileOut( __METHOD__ );
1173
1174                                 return true;
1175                         }
1176                 }
1177
1178                 /*
1179                  * look for JavaScript
1180                  */
1181
1182                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1183                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1184
1185                 # look for script-types
1186                 if ( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1187                         wfDebug( __METHOD__ . ": found script types\n" );
1188                         wfProfileOut( __METHOD__ );
1189
1190                         return true;
1191                 }
1192
1193                 # look for html-style script-urls
1194                 if ( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1195                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1196                         wfProfileOut( __METHOD__ );
1197
1198                         return true;
1199                 }
1200
1201                 # look for css-style script-urls
1202                 if ( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1203                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1204                         wfProfileOut( __METHOD__ );
1205
1206                         return true;
1207                 }
1208
1209                 wfDebug( __METHOD__ . ": no scripts found\n" );
1210                 wfProfileOut( __METHOD__ );
1211
1212                 return false;
1213         }
1214
1215         /**
1216          * Check a whitelist of xml encodings that are known not to be interpreted differently
1217          * by the server's xml parser (expat) and some common browsers.
1218          *
1219          * @param string $file Pathname to the temporary upload file
1220          * @return bool True if the file contains an encoding that could be misinterpreted
1221          */
1222         public static function checkXMLEncodingMissmatch( $file ) {
1223                 global $wgSVGMetadataCutoff;
1224                 $contents = file_get_contents( $file, false, null, -1, $wgSVGMetadataCutoff );
1225                 $encodingRegex = '!encoding[ \t\n\r]*=[ \t\n\r]*[\'"](.*?)[\'"]!si';
1226
1227                 if ( preg_match( "!<\?xml\b(.*?)\?>!si", $contents, $matches ) ) {
1228                         if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1229                                 && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1230                         ) {
1231                                 wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1232
1233                                 return true;
1234                         }
1235                 } elseif ( preg_match( "!<\?xml\b!si", $contents ) ) {
1236                         // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1237                         // bytes. There shouldn't be a legitimate reason for this to happen.
1238                         wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1239
1240                         return true;
1241                 } elseif ( substr( $contents, 0, 4 ) == "\x4C\x6F\xA7\x94" ) {
1242                         // EBCDIC encoded XML
1243                         wfDebug( __METHOD__ . ": EBCDIC Encoded XML\n" );
1244
1245                         return true;
1246                 }
1247
1248                 // It's possible the file is encoded with multi-byte encoding, so re-encode attempt to
1249                 // detect the encoding in case is specifies an encoding not whitelisted in self::$safeXmlEncodings
1250                 $attemptEncodings = array( 'UTF-16', 'UTF-16BE', 'UTF-32', 'UTF-32BE' );
1251                 foreach ( $attemptEncodings as $encoding ) {
1252                         wfSuppressWarnings();
1253                         $str = iconv( $encoding, 'UTF-8', $contents );
1254                         wfRestoreWarnings();
1255                         if ( $str != '' && preg_match( "!<\?xml\b(.*?)\?>!si", $str, $matches ) ) {
1256                                 if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1257                                         && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1258                                 ) {
1259                                         wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1260
1261                                         return true;
1262                                 }
1263                         } elseif ( $str != '' && preg_match( "!<\?xml\b!si", $str ) ) {
1264                                 // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1265                                 // bytes. There shouldn't be a legitimate reason for this to happen.
1266                                 wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1267
1268                                 return true;
1269                         }
1270                 }
1271
1272                 return false;
1273         }
1274
1275         /**
1276          * @param string $filename
1277          * @return mixed False of the file is verified (does not contain scripts), array otherwise.
1278          */
1279         protected function detectScriptInSvg( $filename ) {
1280                 $this->mSVGNSError = false;
1281                 $check = new XmlTypeCheck(
1282                         $filename,
1283                         array( $this, 'checkSvgScriptCallback' ),
1284                         true,
1285                         array( 'processing_instruction_handler' => 'UploadBase::checkSvgPICallback' )
1286                 );
1287                 if ( $check->wellFormed !== true ) {
1288                         // Invalid xml (bug 58553)
1289                         return array( 'uploadinvalidxml' );
1290                 } elseif ( $check->filterMatch ) {
1291                         if ( $this->mSVGNSError ) {
1292                                 return array( 'uploadscriptednamespace', $this->mSVGNSError );
1293                         }
1294
1295                         return array( 'uploadscripted' );
1296                 }
1297
1298                 return false;
1299         }
1300
1301         /**
1302          * Callback to filter SVG Processing Instructions.
1303          * @param string $target Processing instruction name
1304          * @param string $data Processing instruction attribute and value
1305          * @return bool (true if the filter identified something bad)
1306          */
1307         public static function checkSvgPICallback( $target, $data ) {
1308                 // Don't allow external stylesheets (bug 57550)
1309                 if ( preg_match( '/xml-stylesheet/i', $target ) ) {
1310                         return true;
1311                 }
1312
1313                 return false;
1314         }
1315
1316         /**
1317          * @todo Replace this with a whitelist filter!
1318          * @param string $element
1319          * @param array $attribs
1320          * @return bool
1321          */
1322         public function checkSvgScriptCallback( $element, $attribs ) {
1323                 list( $namespace, $strippedElement ) = $this->splitXmlNamespace( $element );
1324
1325                 // We specifically don't include:
1326                 // http://www.w3.org/1999/xhtml (bug 60771)
1327                 static $validNamespaces = array(
1328                         '',
1329                         'adobe:ns:meta/',
1330                         'http://creativecommons.org/ns#',
1331                         'http://inkscape.sourceforge.net/dtd/sodipodi-0.dtd',
1332                         'http://ns.adobe.com/adobeillustrator/10.0/',
1333                         'http://ns.adobe.com/adobesvgviewerextensions/3.0/',
1334                         'http://ns.adobe.com/extensibility/1.0/',
1335                         'http://ns.adobe.com/flows/1.0/',
1336                         'http://ns.adobe.com/illustrator/1.0/',
1337                         'http://ns.adobe.com/imagereplacement/1.0/',
1338                         'http://ns.adobe.com/pdf/1.3/',
1339                         'http://ns.adobe.com/photoshop/1.0/',
1340                         'http://ns.adobe.com/saveforweb/1.0/',
1341                         'http://ns.adobe.com/variables/1.0/',
1342                         'http://ns.adobe.com/xap/1.0/',
1343                         'http://ns.adobe.com/xap/1.0/g/',
1344                         'http://ns.adobe.com/xap/1.0/g/img/',
1345                         'http://ns.adobe.com/xap/1.0/mm/',
1346                         'http://ns.adobe.com/xap/1.0/rights/',
1347                         'http://ns.adobe.com/xap/1.0/stype/dimensions#',
1348                         'http://ns.adobe.com/xap/1.0/stype/font#',
1349                         'http://ns.adobe.com/xap/1.0/stype/manifestitem#',
1350                         'http://ns.adobe.com/xap/1.0/stype/resourceevent#',
1351                         'http://ns.adobe.com/xap/1.0/stype/resourceref#',
1352                         'http://ns.adobe.com/xap/1.0/t/pg/',
1353                         'http://purl.org/dc/elements/1.1/',
1354                         'http://purl.org/dc/elements/1.1',
1355                         'http://schemas.microsoft.com/visio/2003/svgextensions/',
1356                         'http://sodipodi.sourceforge.net/dtd/sodipodi-0.dtd',
1357                         'http://taptrix.com/inkpad/svg_extensions',
1358                         'http://web.resource.org/cc/',
1359                         'http://www.freesoftware.fsf.org/bkchem/cdml',
1360                         'http://www.inkscape.org/namespaces/inkscape',
1361                         'http://www.opengis.net/gml',
1362                         'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
1363                         'http://www.w3.org/2000/svg',
1364                         'http://www.w3.org/tr/rec-rdf-syntax/',
1365                 );
1366
1367                 if ( !in_array( $namespace, $validNamespaces ) ) {
1368                         wfDebug( __METHOD__ . ": Non-svg namespace '$namespace' in uploaded file.\n" );
1369                         /** @todo Return a status object to a closure in XmlTypeCheck, for MW1.21+ */
1370                         $this->mSVGNSError = $namespace;
1371
1372                         return true;
1373                 }
1374
1375                 /*
1376                  * check for elements that can contain javascript
1377                  */
1378                 if ( $strippedElement == 'script' ) {
1379                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1380
1381                         return true;
1382                 }
1383
1384                 # e.g., <svg xmlns="http://www.w3.org/2000/svg">
1385                 #  <handler xmlns:ev="http://www.w3.org/2001/xml-events" ev:event="load">alert(1)</handler> </svg>
1386                 if ( $strippedElement == 'handler' ) {
1387                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1388
1389                         return true;
1390                 }
1391
1392                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1393                 if ( $strippedElement == 'stylesheet' ) {
1394                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1395
1396                         return true;
1397                 }
1398
1399                 # Block iframes, in case they pass the namespace check
1400                 if ( $strippedElement == 'iframe' ) {
1401                         wfDebug( __METHOD__ . ": iframe in uploaded file.\n" );
1402
1403                         return true;
1404                 }
1405
1406                 foreach ( $attribs as $attrib => $value ) {
1407                         $stripped = $this->stripXmlNamespace( $attrib );
1408                         $value = strtolower( $value );
1409
1410                         if ( substr( $stripped, 0, 2 ) == 'on' ) {
1411                                 wfDebug( __METHOD__
1412                                         . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1413
1414                                 return true;
1415                         }
1416
1417                         # href with non-local target (don't allow http://, javascript:, etc)
1418                         if ( $stripped == 'href'
1419                                 && strpos( $value, 'data:' ) !== 0
1420                                 && strpos( $value, '#' ) !== 0
1421                         ) {
1422                                 if ( !( $strippedElement === 'a'
1423                                         && preg_match( '!^https?://!im', $value ) )
1424                                 ) {
1425                                         wfDebug( __METHOD__ . ": Found href attribute <$strippedElement "
1426                                                 . "'$attrib'='$value' in uploaded file.\n" );
1427
1428                                         return true;
1429                                 }
1430                         }
1431
1432                         # href with embedded svg as target
1433                         if ( $stripped == 'href' && preg_match( '!data:[^,]*image/svg[^,]*,!sim', $value ) ) {
1434                                 wfDebug( __METHOD__ . ": Found href to embedded svg "
1435                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1436
1437                                 return true;
1438                         }
1439
1440                         # href with embedded (text/xml) svg as target
1441                         if ( $stripped == 'href' && preg_match( '!data:[^,]*text/xml[^,]*,!sim', $value ) ) {
1442                                 wfDebug( __METHOD__ . ": Found href to embedded svg "
1443                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1444
1445                                 return true;
1446                         }
1447
1448                         # use set/animate to add event-handler attribute to parent
1449                         if ( ( $strippedElement == 'set' || $strippedElement == 'animate' )
1450                                 && $stripped == 'attributename'
1451                                 && substr( $value, 0, 2 ) == 'on'
1452                         ) {
1453                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with "
1454                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1455
1456                                 return true;
1457                         }
1458
1459                         # use set to add href attribute to parent element
1460                         if ( $strippedElement == 'set'
1461                                 && $stripped == 'attributename'
1462                                 && strpos( $value, 'href' ) !== false
1463                         ) {
1464                                 wfDebug( __METHOD__ . ": Found svg setting href attribute '$value' in uploaded file.\n" );
1465
1466                                 return true;
1467                         }
1468
1469                         # use set to add a remote / data / script target to an element
1470                         if ( $strippedElement == 'set'
1471                                 && $stripped == 'to'
1472                                 && preg_match( '!(http|https|data|script):!sim', $value )
1473                         ) {
1474                                 wfDebug( __METHOD__ . ": Found svg setting attribute to '$value' in uploaded file.\n" );
1475
1476                                 return true;
1477                         }
1478
1479                         # use handler attribute with remote / data / script
1480                         if ( $stripped == 'handler' && preg_match( '!(http|https|data|script):!sim', $value ) ) {
1481                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script "
1482                                         . "'$attrib'='$value' in uploaded file.\n" );
1483
1484                                 return true;
1485                         }
1486
1487                         # use CSS styles to bring in remote code
1488                         # catch url("http:..., url('http:..., url(http:..., but not url("#..., url('#..., url(#....
1489                         $tagsList = "font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke";
1490                         if ( $stripped == 'style'
1491                                 && preg_match_all(
1492                                         '!((?:' . $tagsList . ')\s*:\s*url\s*\(\s*["\']?\s*[^#]+.*?\))!sim',
1493                                         $value,
1494                                         $matches
1495                                 )
1496                         ) {
1497                                 foreach ( $matches[1] as $match ) {
1498                                         if ( !preg_match( '!(?:' . $tagsList . ')\s*:\s*url\s*\(\s*(#|\'#|"#)!sim', $match ) ) {
1499                                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1500                                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1501
1502                                                 return true;
1503                                         }
1504                                 }
1505                         }
1506
1507                         # image filters can pull in url, which could be svg that executes scripts
1508                         if ( $strippedElement == 'image'
1509                                 && $stripped == 'filter'
1510                                 && preg_match( '!url\s*\(!sim', $value )
1511                         ) {
1512                                 wfDebug( __METHOD__ . ": Found image filter with url: "
1513                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1514
1515                                 return true;
1516                         }
1517                 }
1518
1519                 return false; //No scripts detected
1520         }
1521
1522         /**
1523          * Divide the element name passed by the xml parser to the callback into URI and prifix.
1524          * @param string $element
1525          * @return array Containing the namespace URI and prefix
1526          */
1527         private static function splitXmlNamespace( $element ) {
1528                 // 'http://www.w3.org/2000/svg:script' -> array( 'http://www.w3.org/2000/svg', 'script' )
1529                 $parts = explode( ':', strtolower( $element ) );
1530                 $name = array_pop( $parts );
1531                 $ns = implode( ':', $parts );
1532
1533                 return array( $ns, $name );
1534         }
1535
1536         /**
1537          * @param string $name
1538          * @return string
1539          */
1540         private function stripXmlNamespace( $name ) {
1541                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1542                 $parts = explode( ':', strtolower( $name ) );
1543
1544                 return array_pop( $parts );
1545         }
1546
1547         /**
1548          * Generic wrapper function for a virus scanner program.
1549          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1550          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1551          *
1552          * @param string $file Pathname to the temporary upload file
1553          * @return mixed False if not virus is found, null if the scan fails or is disabled,
1554          *   or a string containing feedback from the virus scanner if a virus was found.
1555          *   If textual feedback is missing but a virus was found, this function returns true.
1556          */
1557         public static function detectVirus( $file ) {
1558                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1559                 wfProfileIn( __METHOD__ );
1560
1561                 if ( !$wgAntivirus ) {
1562                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1563                         wfProfileOut( __METHOD__ );
1564
1565                         return null;
1566                 }
1567
1568                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1569                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1570                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1571                                 array( 'virus-badscanner', $wgAntivirus ) );
1572                         wfProfileOut( __METHOD__ );
1573
1574                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1575                 }
1576
1577                 # look up scanner configuration
1578                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1579                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1580                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
1581                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
1582
1583                 if ( strpos( $command, "%f" ) === false ) {
1584                         # simple pattern: append file to scan
1585                         $command .= " " . wfEscapeShellArg( $file );
1586                 } else {
1587                         # complex pattern: replace "%f" with file to scan
1588                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
1589                 }
1590
1591                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1592
1593                 # execute virus scanner
1594                 $exitCode = false;
1595
1596                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1597                 #      that does not seem to be worth the pain.
1598                 #      Ask me (Duesentrieb) about it if it's ever needed.
1599                 $output = wfShellExecWithStderr( $command, $exitCode );
1600
1601                 # map exit code to AV_xxx constants.
1602                 $mappedCode = $exitCode;
1603                 if ( $exitCodeMap ) {
1604                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1605                                 $mappedCode = $exitCodeMap[$exitCode];
1606                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1607                                 $mappedCode = $exitCodeMap["*"];
1608                         }
1609                 }
1610
1611                 /* NB: AV_NO_VIRUS is 0 but AV_SCAN_FAILED is false,
1612                  * so we need the strict equalities === and thus can't use a switch here
1613                  */
1614                 if ( $mappedCode === AV_SCAN_FAILED ) {
1615                         # scan failed (code was mapped to false by $exitCodeMap)
1616                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1617
1618                         $output = $wgAntivirusRequired
1619                                 ? wfMessage( 'virus-scanfailed', array( $exitCode ) )->text()
1620                                 : null;
1621                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1622                         # scan failed because filetype is unknown (probably imune)
1623                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1624                         $output = null;
1625                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1626                         # no virus found
1627                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1628                         $output = false;
1629                 } else {
1630                         $output = trim( $output );
1631
1632                         if ( !$output ) {
1633                                 $output = true; #if there's no output, return true
1634                         } elseif ( $msgPattern ) {
1635                                 $groups = array();
1636                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
1637                                         if ( $groups[1] ) {
1638                                                 $output = $groups[1];
1639                                         }
1640                                 }
1641                         }
1642
1643                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1644                 }
1645
1646                 wfProfileOut( __METHOD__ );
1647
1648                 return $output;
1649         }
1650
1651         /**
1652          * Check if there's an overwrite conflict and, if so, if restrictions
1653          * forbid this user from performing the upload.
1654          *
1655          * @param User $user
1656          *
1657          * @return mixed True on success, array on failure
1658          */
1659         private function checkOverwrite( $user ) {
1660                 // First check whether the local file can be overwritten
1661                 $file = $this->getLocalFile();
1662                 if ( $file->exists() ) {
1663                         if ( !self::userCanReUpload( $user, $file ) ) {
1664                                 return array( 'fileexists-forbidden', $file->getName() );
1665                         } else {
1666                                 return true;
1667                         }
1668                 }
1669
1670                 /* Check shared conflicts: if the local file does not exist, but
1671                  * wfFindFile finds a file, it exists in a shared repository.
1672                  */
1673                 $file = wfFindFile( $this->getTitle() );
1674                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1675                         return array( 'fileexists-shared-forbidden', $file->getName() );
1676                 }
1677
1678                 return true;
1679         }
1680
1681         /**
1682          * Check if a user is the last uploader
1683          *
1684          * @param User $user
1685          * @param string $img Image name
1686          * @return bool
1687          */
1688         public static function userCanReUpload( User $user, $img ) {
1689                 if ( $user->isAllowed( 'reupload' ) ) {
1690                         return true; // non-conditional
1691                 }
1692                 if ( !$user->isAllowed( 'reupload-own' ) ) {
1693                         return false;
1694                 }
1695                 if ( is_string( $img ) ) {
1696                         $img = wfLocalFile( $img );
1697                 }
1698                 if ( !( $img instanceof LocalFile ) ) {
1699                         return false;
1700                 }
1701
1702                 return $user->getId() == $img->getUser( 'id' );
1703         }
1704
1705         /**
1706          * Helper function that does various existence checks for a file.
1707          * The following checks are performed:
1708          * - The file exists
1709          * - Article with the same name as the file exists
1710          * - File exists with normalized extension
1711          * - The file looks like a thumbnail and the original exists
1712          *
1713          * @param File $file The File object to check
1714          * @return mixed False if the file does not exists, else an array
1715          */
1716         public static function getExistsWarning( $file ) {
1717                 if ( $file->exists() ) {
1718                         return array( 'warning' => 'exists', 'file' => $file );
1719                 }
1720
1721                 if ( $file->getTitle()->getArticleID() ) {
1722                         return array( 'warning' => 'page-exists', 'file' => $file );
1723                 }
1724
1725                 if ( $file->wasDeleted() && !$file->exists() ) {
1726                         return array( 'warning' => 'was-deleted', 'file' => $file );
1727                 }
1728
1729                 if ( strpos( $file->getName(), '.' ) == false ) {
1730                         $partname = $file->getName();
1731                         $extension = '';
1732                 } else {
1733                         $n = strrpos( $file->getName(), '.' );
1734                         $extension = substr( $file->getName(), $n + 1 );
1735                         $partname = substr( $file->getName(), 0, $n );
1736                 }
1737                 $normalizedExtension = File::normalizeExtension( $extension );
1738
1739                 if ( $normalizedExtension != $extension ) {
1740                         // We're not using the normalized form of the extension.
1741                         // Normal form is lowercase, using most common of alternate
1742                         // extensions (eg 'jpg' rather than 'JPEG').
1743                         //
1744                         // Check for another file using the normalized form...
1745                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1746                         $file_lc = wfLocalFile( $nt_lc );
1747
1748                         if ( $file_lc->exists() ) {
1749                                 return array(
1750                                         'warning' => 'exists-normalized',
1751                                         'file' => $file,
1752                                         'normalizedFile' => $file_lc
1753                                 );
1754                         }
1755                 }
1756
1757                 // Check for files with the same name but a different extension
1758                 $similarFiles = RepoGroup::singleton()->getLocalRepo()->findFilesByPrefix(
1759                         "{$partname}.", 1 );
1760                 if ( count( $similarFiles ) ) {
1761                         return array(
1762                                 'warning' => 'exists-normalized',
1763                                 'file' => $file,
1764                                 'normalizedFile' => $similarFiles[0],
1765                         );
1766                 }
1767
1768                 if ( self::isThumbName( $file->getName() ) ) {
1769                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1770                         $nt_thb = Title::newFromText(
1771                                 substr( $partname, strpos( $partname, '-' ) + 1 ) . '.' . $extension,
1772                                 NS_FILE
1773                         );
1774                         $file_thb = wfLocalFile( $nt_thb );
1775                         if ( $file_thb->exists() ) {
1776                                 return array(
1777                                         'warning' => 'thumb',
1778                                         'file' => $file,
1779                                         'thumbFile' => $file_thb
1780                                 );
1781                         } else {
1782                                 // File does not exist, but we just don't like the name
1783                                 return array(
1784                                         'warning' => 'thumb-name',
1785                                         'file' => $file,
1786                                         'thumbFile' => $file_thb
1787                                 );
1788                         }
1789                 }
1790
1791                 foreach ( self::getFilenamePrefixBlacklist() as $prefix ) {
1792                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1793                                 return array(
1794                                         'warning' => 'bad-prefix',
1795                                         'file' => $file,
1796                                         'prefix' => $prefix
1797                                 );
1798                         }
1799                 }
1800
1801                 return false;
1802         }
1803
1804         /**
1805          * Helper function that checks whether the filename looks like a thumbnail
1806          * @param string $filename
1807          * @return bool
1808          */
1809         public static function isThumbName( $filename ) {
1810                 $n = strrpos( $filename, '.' );
1811                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1812
1813                 return (
1814                         substr( $partname, 3, 3 ) == 'px-' ||
1815                         substr( $partname, 2, 3 ) == 'px-'
1816                 ) &&
1817                 preg_match( "/[0-9]{2}/", substr( $partname, 0, 2 ) );
1818         }
1819
1820         /**
1821          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1822          *
1823          * @return array List of prefixes
1824          */
1825         public static function getFilenamePrefixBlacklist() {
1826                 $blacklist = array();
1827                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
1828                 if ( !$message->isDisabled() ) {
1829                         $lines = explode( "\n", $message->plain() );
1830                         foreach ( $lines as $line ) {
1831                                 // Remove comment lines
1832                                 $comment = substr( trim( $line ), 0, 1 );
1833                                 if ( $comment == '#' || $comment == '' ) {
1834                                         continue;
1835                                 }
1836                                 // Remove additional comments after a prefix
1837                                 $comment = strpos( $line, '#' );
1838                                 if ( $comment > 0 ) {
1839                                         $line = substr( $line, 0, $comment - 1 );
1840                                 }
1841                                 $blacklist[] = trim( $line );
1842                         }
1843                 }
1844
1845                 return $blacklist;
1846         }
1847
1848         /**
1849          * Gets image info about the file just uploaded.
1850          *
1851          * Also has the effect of setting metadata to be an 'indexed tag name' in
1852          * returned API result if 'metadata' was requested. Oddly, we have to pass
1853          * the "result" object down just so it can do that with the appropriate
1854          * format, presumably.
1855          *
1856          * @param ApiResult $result
1857          * @return array Image info
1858          */
1859         public function getImageInfo( $result ) {
1860                 $file = $this->getLocalFile();
1861                 /** @todo This cries out for refactoring.
1862                  *  We really want to say $file->getAllInfo(); here.
1863                  * Perhaps "info" methods should be moved into files, and the API should
1864                  * just wrap them in queries.
1865                  */
1866                 if ( $file instanceof UploadStashFile ) {
1867                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
1868                         $info = ApiQueryStashImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1869                 } else {
1870                         $imParam = ApiQueryImageInfo::getPropertyNames();
1871                         $info = ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1872                 }
1873
1874                 return $info;
1875         }
1876
1877         /**
1878          * @param array $error
1879          * @return Status
1880          */
1881         public function convertVerifyErrorToStatus( $error ) {
1882                 $code = $error['status'];
1883                 unset( $code['status'] );
1884
1885                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
1886         }
1887
1888         /**
1889          * @param null|string $forType
1890          * @return int
1891          */
1892         public static function getMaxUploadSize( $forType = null ) {
1893                 global $wgMaxUploadSize;
1894
1895                 if ( is_array( $wgMaxUploadSize ) ) {
1896                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
1897                                 return $wgMaxUploadSize[$forType];
1898                         } else {
1899                                 return $wgMaxUploadSize['*'];
1900                         }
1901                 } else {
1902                         return intval( $wgMaxUploadSize );
1903                 }
1904         }
1905
1906         /**
1907          * Get the current status of a chunked upload (used for polling).
1908          * The status will be read from the *current* user session.
1909          * @param string $statusKey
1910          * @return Status[]|bool
1911          */
1912         public static function getSessionStatus( $statusKey ) {
1913                 return isset( $_SESSION[self::SESSION_STATUS_KEY][$statusKey] )
1914                         ? $_SESSION[self::SESSION_STATUS_KEY][$statusKey]
1915                         : false;
1916         }
1917
1918         /**
1919          * Set the current status of a chunked upload (used for polling).
1920          * The status will be stored in the *current* user session.
1921          * @param string $statusKey
1922          * @param array|bool $value
1923          * @return void
1924          */
1925         public static function setSessionStatus( $statusKey, $value ) {
1926                 if ( $value === false ) {
1927                         unset( $_SESSION[self::SESSION_STATUS_KEY][$statusKey] );
1928                 } else {
1929                         $_SESSION[self::SESSION_STATUS_KEY][$statusKey] = $value;
1930                 }
1931         }
1932 }