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         /**
  73          * @param int $error
  74          * @return string
  75          */
  76         public function getVerificationErrorCode( $error ) {
  77                 $code_to_status = array(
  78                         self::EMPTY_FILE => 'empty-file',
  79                         self::FILE_TOO_LARGE => 'file-too-large',
  80                         self::FILETYPE_MISSING => 'filetype-missing',
  81                         self::FILETYPE_BADTYPE => 'filetype-banned',
  82                         self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  83                         self::ILLEGAL_FILENAME => 'illegal-filename',
  84                         self::OVERWRITE_EXISTING_FILE => 'overwrite',
  85                         self::VERIFICATION_ERROR => 'verification-error',
  86                         self::HOOK_ABORTED => 'hookaborted',
  87                         self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
  88                         self::FILENAME_TOO_LONG => 'filename-toolong',
  89                 );
  90                 if ( isset( $code_to_status[$error] ) ) {
  91                         return $code_to_status[$error];
  92                 }
  93
  94                 return 'unknown-error';
  95         }
  96
  97         /**
  98          * Returns true if uploads are enabled.
  99          * Can be override by subclasses.
 100          * @return bool
 101          */
 102         public static function isEnabled() {
 103                 global $wgEnableUploads;
 104
 105                 if ( !$wgEnableUploads ) {
 106                         return false;
 107                 }
 108
 109                 # Check php's file_uploads setting
 110                 return wfIsHHVM() || wfIniGetBool( 'file_uploads' );
 111         }
 112
 113         /**
 114          * Returns true if the user can use this upload module or else a string
 115          * identifying the missing permission.
 116          * Can be overridden by subclasses.
 117          *
 118          * @param User $user
 119          * @return bool|string
 120          */
 121         public static function isAllowed( $user ) {
 122                 foreach ( array( 'upload', 'edit' ) as $permission ) {
 123                         if ( !$user->isAllowed( $permission ) ) {
 124                                 return $permission;
 125                         }
 126                 }
 127
 128                 return true;
 129         }
 130
 131         // Upload handlers. Should probably just be a global.
 132         private static $uploadHandlers = array( 'Stash', 'File', 'Url' );
 133
 134         /**
 135          * Create a form of UploadBase depending on wpSourceType and initializes it
 136          *
 137          * @param WebRequest $request
 138          * @param string|null $type
 139          * @return null|UploadBase
 140          */
 141         public static function createFromRequest( &$request, $type = null ) {
 142                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 143
 144                 if ( !$type ) {
 145                         return null;
 146                 }
 147
 148                 // Get the upload class
 149                 $type = ucfirst( $type );
 150
 151                 // Give hooks the chance to handle this request
 152                 $className = null;
 153                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 154                 if ( is_null( $className ) ) {
 155                         $className = 'UploadFrom' . $type;
 156                         wfDebug( __METHOD__ . ": class name: $className\n" );
 157                         if ( !in_array( $type, self::$uploadHandlers ) ) {
 158                                 return null;
 159                         }
 160                 }
 161
 162                 // Check whether this upload class is enabled
 163                 if ( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 164                         return null;
 165                 }
 166
 167                 // Check whether the request is valid
 168                 if ( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 169                         return null;
 170                 }
 171
 172                 /** @var UploadBase $handler */
 173                 $handler = new $className;
 174
 175                 $handler->initializeFromRequest( $request );
 176
 177                 return $handler;
 178         }
 179
 180         /**
 181          * Check whether a request if valid for this handler
 182          * @param WebRequest $request
 183          * @return bool
 184          */
 185         public static function isValidRequest( $request ) {
 186                 return false;
 187         }
 188
 189         public function __construct() {
 190         }
 191
 192         /**
 193          * Returns the upload type. Should be overridden by child classes
 194          *
 195          * @since 1.18
 196          * @return string
 197          */
 198         public function getSourceType() {
 199                 return null;
 200         }
 201
 202         /**
 203          * Initialize the path information
 204          * @param string $name The desired destination name
 205          * @param string $tempPath The temporary path
 206          * @param int $fileSize The file size
 207          * @param bool $removeTempFile (false) remove the temporary file?
 208          * @throws MWException
 209          */
 210         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 211                 $this->mDesiredDestName = $name;
 212                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 213                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 214                 }
 215                 $this->mTempPath = $tempPath;
 216                 $this->mFileSize = $fileSize;
 217                 $this->mRemoveTempFile = $removeTempFile;
 218         }
 219
 220         /**
 221          * Initialize from a WebRequest. Override this in a subclass.
 222          *
 223          * @param WebRequest $request
 224          */
 225         abstract public function initializeFromRequest( &$request );
 226
 227         /**
 228          * Fetch the file. Usually a no-op
 229          * @return Status
 230          */
 231         public function fetchFile() {
 232                 return Status::newGood();
 233         }
 234
 235         /**
 236          * Return true if the file is empty
 237          * @return bool
 238          */
 239         public function isEmptyFile() {
 240                 return empty( $this->mFileSize );
 241         }
 242
 243         /**
 244          * Return the file size
 245          * @return int
 246          */
 247         public function getFileSize() {
 248                 return $this->mFileSize;
 249         }
 250
 251         /**
 252          * Get the base 36 SHA1 of the file
 253          * @return string
 254          */
 255         public function getTempFileSha1Base36() {
 256                 return FSFile::getSha1Base36FromPath( $this->mTempPath );
 257         }
 258
 259         /**
 260          * @param string $srcPath The source path
 261          * @return string|bool The real path if it was a virtual URL Returns false on failure
 262          */
 263         function getRealPath( $srcPath ) {
 264                 wfProfileIn( __METHOD__ );
 265                 $repo = RepoGroup::singleton()->getLocalRepo();
 266                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 267                         /** @todo Just make uploads work with storage paths UploadFromStash
 268                          *  loads files via virtual URLs.
 269                          */
 270                         $tmpFile = $repo->getLocalCopy( $srcPath );
 271                         if ( $tmpFile ) {
 272                                 $tmpFile->bind( $this ); // keep alive with $this
 273                         }
 274                         $path = $tmpFile ? $tmpFile->getPath() : false;
 275                 } else {
 276                         $path = $srcPath;
 277                 }
 278                 wfProfileOut( __METHOD__ );
 279
 280                 return $path;
 281         }
 282
 283         /**
 284          * Verify whether the upload is sane.
 285          * @return mixed Const self::OK or else an array with error information
 286          */
 287         public function verifyUpload() {
 288                 wfProfileIn( __METHOD__ );
 289
 290                 /**
 291                  * If there was no filename or a zero size given, give up quick.
 292                  */
 293                 if ( $this->isEmptyFile() ) {
 294                         wfProfileOut( __METHOD__ );
 295
 296                         return array( 'status' => self::EMPTY_FILE );
 297                 }
 298
 299                 /**
 300                  * Honor $wgMaxUploadSize
 301                  */
 302                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 303                 if ( $this->mFileSize > $maxSize ) {
 304                         wfProfileOut( __METHOD__ );
 305
 306                         return array(
 307                                 'status' => self::FILE_TOO_LARGE,
 308                                 'max' => $maxSize,
 309                         );
 310                 }
 311
 312                 /**
 313                  * Look at the contents of the file; if we can recognize the
 314                  * type but it's corrupt or data of the wrong type, we should
 315                  * probably not accept it.
 316                  */
 317                 $verification = $this->verifyFile();
 318                 if ( $verification !== true ) {
 319                         wfProfileOut( __METHOD__ );
 320
 321                         return array(
 322                                 'status' => self::VERIFICATION_ERROR,
 323                                 'details' => $verification
 324                         );
 325                 }
 326
 327                 /**
 328                  * Make sure this file can be created
 329                  */
 330                 $result = $this->validateName();
 331                 if ( $result !== true ) {
 332                         wfProfileOut( __METHOD__ );
 333
 334                         return $result;
 335                 }
 336
 337                 $error = '';
 338                 if ( !wfRunHooks( 'UploadVerification',
 339                         array( $this->mDestName, $this->mTempPath, &$error ) )
 340                 ) {
 341                         wfProfileOut( __METHOD__ );
 342
 343                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 344                 }
 345
 346                 wfProfileOut( __METHOD__ );
 347
 348                 return array( 'status' => self::OK );
 349         }
 350
 351         /**
 352          * Verify that the name is valid and, if necessary, that we can overwrite
 353          *
 354          * @return mixed True if valid, otherwise and array with 'status'
 355          * and other keys
 356          */
 357         public function validateName() {
 358                 $nt = $this->getTitle();
 359                 if ( is_null( $nt ) ) {
 360                         $result = array( 'status' => $this->mTitleError );
 361                         if ( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 362                                 $result['filtered'] = $this->mFilteredName;
 363                         }
 364                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 365                                 $result['finalExt'] = $this->mFinalExtension;
 366                                 if ( count( $this->mBlackListedExtensions ) ) {
 367                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 368                                 }
 369                         }
 370
 371                         return $result;
 372                 }
 373                 $this->mDestName = $this->getLocalFile()->getName();
 374
 375                 return true;
 376         }
 377
 378         /**
 379          * Verify the MIME type.
 380          *
 381          * @note Only checks that it is not an evil MIME. The "does it have
 382          *  correct extension given its MIME type?" check is in verifyFile.
 383          *  in `verifyFile()` that MIME type and file extension correlate.
 384          * @param string $mime Representing the MIME
 385          * @return mixed True if the file is verified, an array otherwise
 386          */
 387         protected function verifyMimeType( $mime ) {
 388                 global $wgVerifyMimeType;
 389                 wfProfileIn( __METHOD__ );
 390                 if ( $wgVerifyMimeType ) {
 391                         wfDebug( "mime: <$mime> extension: <{$this->mFinalExtension}>\n" );
 392                         global $wgMimeTypeBlacklist;
 393                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 394                                 wfProfileOut( __METHOD__ );
 395
 396                                 return array( 'filetype-badmime', $mime );
 397                         }
 398
 399                         # Check what Internet Explorer would detect
 400                         $fp = fopen( $this->mTempPath, 'rb' );
 401                         $chunk = fread( $fp, 256 );
 402                         fclose( $fp );
 403
 404                         $magic = MimeMagic::singleton();
 405                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 406                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 407                         foreach ( $ieTypes as $ieType ) {
 408                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 409                                         wfProfileOut( __METHOD__ );
 410
 411                                         return array( 'filetype-bad-ie-mime', $ieType );
 412                                 }
 413                         }
 414                 }
 415
 416                 wfProfileOut( __METHOD__ );
 417
 418                 return true;
 419         }
 420
 421         /**
 422          * Verifies that it's ok to include the uploaded file
 423          *
 424          * @return mixed True of the file is verified, array otherwise.
 425          */
 426         protected function verifyFile() {
 427                 global $wgVerifyMimeType, $wgDisableUploadScriptChecks;
 428                 wfProfileIn( __METHOD__ );
 429
 430                 $status = $this->verifyPartialFile();
 431                 if ( $status !== true ) {
 432                         wfProfileOut( __METHOD__ );
 433
 434                         return $status;
 435                 }
 436
 437                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 438                 $mime = $this->mFileProps['mime'];
 439
 440                 if ( $wgVerifyMimeType ) {
 441                         # XXX: Missing extension will be caught by validateName() via getTitle()
 442                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 443                                 wfProfileOut( __METHOD__ );
 444
 445                                 return array( 'filetype-mime-mismatch', $this->mFinalExtension, $mime );
 446                         }
 447                 }
 448
 449                 # check for htmlish code and javascript
 450                 if ( !$wgDisableUploadScriptChecks ) {
 451                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 452                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath, false );
 453                                 if ( $svgStatus !== false ) {
 454                                         wfProfileOut( __METHOD__ );
 455
 456                                         return $svgStatus;
 457                                 }
 458                         }
 459                 }
 460
 461                 $handler = MediaHandler::getHandler( $mime );
 462                 if ( $handler ) {
 463                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 464                         if ( !$handlerStatus->isOK() ) {
 465                                 $errors = $handlerStatus->getErrorsArray();
 466                                 wfProfileOut( __METHOD__ );
 467
 468                                 return reset( $errors );
 469                         }
 470                 }
 471
 472                 wfRunHooks( 'UploadVerifyFile', array( $this, $mime, &$status ) );
 473                 if ( $status !== true ) {
 474                         wfProfileOut( __METHOD__ );
 475
 476                         return $status;
 477                 }
 478
 479                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 480                 wfProfileOut( __METHOD__ );
 481
 482                 return true;
 483         }
 484
 485         /**
 486          * A verification routine suitable for partial files
 487          *
 488          * Runs the blacklist checks, but not any checks that may
 489          * assume the entire file is present.
 490          *
 491          * @return mixed True for valid or array with error message key.
 492          */
 493         protected function verifyPartialFile() {
 494                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 495                 wfProfileIn( __METHOD__ );
 496
 497                 # getTitle() sets some internal parameters like $this->mFinalExtension
 498                 $this->getTitle();
 499
 500                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 501
 502                 # check MIME type, if desired
 503                 $mime = $this->mFileProps['file-mime'];
 504                 $status = $this->verifyMimeType( $mime );
 505                 if ( $status !== true ) {
 506                         wfProfileOut( __METHOD__ );
 507
 508                         return $status;
 509                 }
 510
 511                 # check for htmlish code and javascript
 512                 if ( !$wgDisableUploadScriptChecks ) {
 513                         if ( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 514                                 wfProfileOut( __METHOD__ );
 515
 516                                 return array( 'uploadscripted' );
 517                         }
 518                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 519                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath, true );
 520                                 if ( $svgStatus !== false ) {
 521                                         wfProfileOut( __METHOD__ );
 522
 523                                         return $svgStatus;
 524                                 }
 525                         }
 526                 }
 527
 528                 # Check for Java applets, which if uploaded can bypass cross-site
 529                 # restrictions.
 530                 if ( !$wgAllowJavaUploads ) {
 531                         $this->mJavaDetected = false;
 532                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 533                                 array( $this, 'zipEntryCallback' ) );
 534                         if ( !$zipStatus->isOK() ) {
 535                                 $errors = $zipStatus->getErrorsArray();
 536                                 $error = reset( $errors );
 537                                 if ( $error[0] !== 'zip-wrong-format' ) {
 538                                         wfProfileOut( __METHOD__ );
 539
 540                                         return $error;
 541                                 }
 542                         }
 543                         if ( $this->mJavaDetected ) {
 544                                 wfProfileOut( __METHOD__ );
 545
 546                                 return array( 'uploadjava' );
 547                         }
 548                 }
 549
 550                 # Scan the uploaded file for viruses
 551                 $virus = $this->detectVirus( $this->mTempPath );
 552                 if ( $virus ) {
 553                         wfProfileOut( __METHOD__ );
 554
 555                         return array( 'uploadvirus', $virus );
 556                 }
 557
 558                 wfProfileOut( __METHOD__ );
 559
 560                 return true;
 561         }
 562
 563         /**
 564          * Callback for ZipDirectoryReader to detect Java class files.
 565          *
 566          * @param array $entry
 567          */
 568         function zipEntryCallback( $entry ) {
 569                 $names = array( $entry['name'] );
 570
 571                 // If there is a null character, cut off the name at it, because JDK's
 572                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 573                 // were constructed which had ".class\0" followed by a string chosen to
 574                 // make the hash collide with the truncated name, that file could be
 575                 // returned in response to a request for the .class file.
 576                 $nullPos = strpos( $entry['name'], "\000" );
 577                 if ( $nullPos !== false ) {
 578                         $names[] = substr( $entry['name'], 0, $nullPos );
 579                 }
 580
 581                 // If there is a trailing slash in the file name, we have to strip it,
 582                 // because that's what ZIP_GetEntry() does.
 583                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 584                         $this->mJavaDetected = true;
 585                 }
 586         }
 587
 588         /**
 589          * Alias for verifyTitlePermissions. The function was originally
 590          * 'verifyPermissions', but that suggests it's checking the user, when it's
 591          * really checking the title + user combination.
 592          *
 593          * @param User $user User object to verify the permissions against
 594          * @return mixed An array as returned by getUserPermissionsErrors or true
 595          *   in case the user has proper permissions.
 596          */
 597         public function verifyPermissions( $user ) {
 598                 return $this->verifyTitlePermissions( $user );
 599         }
 600
 601         /**
 602          * Check whether the user can edit, upload and create the image. This
 603          * checks only against the current title; if it returns errors, it may
 604          * very well be that another title will not give errors. Therefore
 605          * isAllowed() should be called as well for generic is-user-blocked or
 606          * can-user-upload checking.
 607          *
 608          * @param User $user User object to verify the permissions against
 609          * @return mixed An array as returned by getUserPermissionsErrors or true
 610          *   in case the user has proper permissions.
 611          */
 612         public function verifyTitlePermissions( $user ) {
 613                 /**
 614                  * If the image is protected, non-sysop users won't be able
 615                  * to modify it by uploading a new revision.
 616                  */
 617                 $nt = $this->getTitle();
 618                 if ( is_null( $nt ) ) {
 619                         return true;
 620                 }
 621                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 622                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 623                 if ( !$nt->exists() ) {
 624                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 625                 } else {
 626                         $permErrorsCreate = array();
 627                 }
 628                 if ( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 629                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 630                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 631
 632                         return $permErrors;
 633                 }
 634
 635                 $overwriteError = $this->checkOverwrite( $user );
 636                 if ( $overwriteError !== true ) {
 637                         return array( $overwriteError );
 638                 }
 639
 640                 return true;
 641         }
 642
 643         /**
 644          * Check for non fatal problems with the file.
 645          *
 646          * This should not assume that mTempPath is set.
 647          *
 648          * @return array Array of warnings
 649          */
 650         public function checkWarnings() {
 651                 global $wgLang;
 652                 wfProfileIn( __METHOD__ );
 653
 654                 $warnings = array();
 655
 656                 $localFile = $this->getLocalFile();
 657                 $filename = $localFile->getName();
 658
 659                 /**
 660                  * Check whether the resulting filename is different from the desired one,
 661                  * but ignore things like ucfirst() and spaces/underscore things
 662                  */
 663                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 664                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 665
 666                 if ( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 667                         $warnings['badfilename'] = $filename;
 668                         // Debugging for bug 62241
 669                         wfDebugLog( 'upload', "Filename: '$filename', mDesiredDestName: "
 670                                 . "'$this->mDesiredDestName', comparableName: '$comparableName'" );
 671                 }
 672
 673                 // Check whether the file extension is on the unwanted list
 674                 global $wgCheckFileExtensions, $wgFileExtensions;
 675                 if ( $wgCheckFileExtensions ) {
 676                         $extensions = array_unique( $wgFileExtensions );
 677                         if ( !$this->checkFileExtension( $this->mFinalExtension, $extensions ) ) {
 678                                 $warnings['filetype-unwanted-type'] = array( $this->mFinalExtension,
 679                                         $wgLang->commaList( $extensions ), count( $extensions ) );
 680                         }
 681                 }
 682
 683                 global $wgUploadSizeWarning;
 684                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 685                         $warnings['large-file'] = array( $wgUploadSizeWarning, $this->mFileSize );
 686                 }
 687
 688                 if ( $this->mFileSize == 0 ) {
 689                         $warnings['emptyfile'] = true;
 690                 }
 691
 692                 $exists = self::getExistsWarning( $localFile );
 693                 if ( $exists !== false ) {
 694                         $warnings['exists'] = $exists;
 695                 }
 696
 697                 // Check dupes against existing files
 698                 $hash = $this->getTempFileSha1Base36();
 699                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 700                 $title = $this->getTitle();
 701                 // Remove all matches against self
 702                 foreach ( $dupes as $key => $dupe ) {
 703                         if ( $title->equals( $dupe->getTitle() ) ) {
 704                                 unset( $dupes[$key] );
 705                         }
 706                 }
 707                 if ( $dupes ) {
 708                         $warnings['duplicate'] = $dupes;
 709                 }
 710
 711                 // Check dupes against archives
 712                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 713                 if ( $archivedImage->getID() > 0 ) {
 714                         if ( $archivedImage->userCan( File::DELETED_FILE ) ) {
 715                                 $warnings['duplicate-archive'] = $archivedImage->getName();
 716                         } else {
 717                                 $warnings['duplicate-archive'] = '';
 718                         }
 719                 }
 720
 721                 wfProfileOut( __METHOD__ );
 722
 723                 return $warnings;
 724         }
 725
 726         /**
 727          * Really perform the upload. Stores the file in the local repo, watches
 728          * if necessary and runs the UploadComplete hook.
 729          *
 730          * @param string $comment
 731          * @param string $pageText
 732          * @param bool $watch
 733          * @param User $user
 734          *
 735          * @return Status Indicating the whether the upload succeeded.
 736          */
 737         public function performUpload( $comment, $pageText, $watch, $user ) {
 738                 wfProfileIn( __METHOD__ );
 739
 740                 $status = $this->getLocalFile()->upload(
 741                         $this->mTempPath,
 742                         $comment,
 743                         $pageText,
 744                         File::DELETE_SOURCE,
 745                         $this->mFileProps,
 746                         false,
 747                         $user
 748                 );
 749
 750                 if ( $status->isGood() ) {
 751                         if ( $watch ) {
 752                                 WatchAction::doWatch(
 753                                         $this->getLocalFile()->getTitle(),
 754                                         $user,
 755                                         WatchedItem::IGNORE_USER_RIGHTS
 756                                 );
 757                         }
 758                         wfRunHooks( 'UploadComplete', array( &$this ) );
 759
 760                         $this->postProcessUpload();
 761                 }
 762
 763                 wfProfileOut( __METHOD__ );
 764
 765                 return $status;
 766         }
 767
 768         /**
 769          * Perform extra steps after a successful upload.
 770          *
 771          * @since  1.25
 772          */
 773         public function postProcessUpload() {
 774                 global $wgUploadThumbnailRenderMap;
 775
 776                 $jobs = array();
 777
 778                 $sizes = $wgUploadThumbnailRenderMap;
 779                 rsort( $sizes );
 780
 781                 foreach ( $sizes as $size ) {
 782                         $jobs[] = new ThumbnailRenderJob( $this->getLocalFile()->getTitle(), array(
 783                                 'transformParams' => array( 'width' => $size ),
 784                         ) );
 785                 }
 786
 787                 JobQueueGroup::singleton()->push( $jobs );
 788         }
 789
 790         /**
 791          * Returns the title of the file to be uploaded. Sets mTitleError in case
 792          * the name was illegal.
 793          *
 794          * @return Title The title of the file or null in case the name was illegal
 795          */
 796         public function getTitle() {
 797                 if ( $this->mTitle !== false ) {
 798                         return $this->mTitle;
 799                 }
 800                 /* Assume that if a user specified File:Something.jpg, this is an error
 801                  * and that the namespace prefix needs to be stripped of.
 802                  */
 803                 $title = Title::newFromText( $this->mDesiredDestName );
 804                 if ( $title && $title->getNamespace() == NS_FILE ) {
 805                         $this->mFilteredName = $title->getDBkey();
 806                 } else {
 807                         $this->mFilteredName = $this->mDesiredDestName;
 808                 }
 809
 810                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 811                 # exclamation mark, so restrict file name to 240 bytes.
 812                 if ( strlen( $this->mFilteredName ) > 240 ) {
 813                         $this->mTitleError = self::FILENAME_TOO_LONG;
 814                         $this->mTitle = null;
 815
 816                         return $this->mTitle;
 817                 }
 818
 819                 /**
 820                  * Chop off any directories in the given filename. Then
 821                  * filter out illegal characters, and try to make a legible name
 822                  * out of it. We'll strip some silently that Title would die on.
 823                  */
 824                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 825                 /* Normalize to title form before we do any further processing */
 826                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 827                 if ( is_null( $nt ) ) {
 828                         $this->mTitleError = self::ILLEGAL_FILENAME;
 829                         $this->mTitle = null;
 830
 831                         return $this->mTitle;
 832                 }
 833                 $this->mFilteredName = $nt->getDBkey();
 834
 835                 /**
 836                  * We'll want to blacklist against *any* 'extension', and use
 837                  * only the final one for the whitelist.
 838                  */
 839                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 840
 841                 if ( count( $ext ) ) {
 842                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 843                 } else {
 844                         $this->mFinalExtension = '';
 845
 846                         # No extension, try guessing one
 847                         $magic = MimeMagic::singleton();
 848                         $mime = $magic->guessMimeType( $this->mTempPath );
 849                         if ( $mime !== 'unknown/unknown' ) {
 850                                 # Get a space separated list of extensions
 851                                 $extList = $magic->getExtensionsForType( $mime );
 852                                 if ( $extList ) {
 853                                         # Set the extension to the canonical extension
 854                                         $this->mFinalExtension = strtok( $extList, ' ' );
 855
 856                                         # Fix up the other variables
 857                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 858                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 859                                         $ext = array( $this->mFinalExtension );
 860                                 }
 861                         }
 862                 }
 863
 864                 /* Don't allow users to override the blacklist (check file extension) */
 865                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 866                 global $wgFileExtensions, $wgFileBlacklist;
 867
 868                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 869
 870                 if ( $this->mFinalExtension == '' ) {
 871                         $this->mTitleError = self::FILETYPE_MISSING;
 872                         $this->mTitle = null;
 873
 874                         return $this->mTitle;
 875                 } elseif ( $blackListedExtensions ||
 876                         ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 877                                 !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) )
 878                 ) {
 879                         $this->mBlackListedExtensions = $blackListedExtensions;
 880                         $this->mTitleError = self::FILETYPE_BADTYPE;
 881                         $this->mTitle = null;
 882
 883                         return $this->mTitle;
 884                 }
 885
 886                 // Windows may be broken with special characters, see bug 1780
 887                 if ( !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() )
 888                         && !RepoGroup::singleton()->getLocalRepo()->backendSupportsUnicodePaths()
 889                 ) {
 890                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
 891                         $this->mTitle = null;
 892
 893                         return $this->mTitle;
 894                 }
 895
 896                 # If there was more than one "extension", reassemble the base
 897                 # filename to prevent bogus complaints about length
 898                 if ( count( $ext ) > 1 ) {
 899                         $iterations = count( $ext ) - 1;
 900                         for ( $i = 0; $i < $iterations; $i++ ) {
 901                                 $partname .= '.' . $ext[$i];
 902                         }
 903                 }
 904
 905                 if ( strlen( $partname ) < 1 ) {
 906                         $this->mTitleError = self::MIN_LENGTH_PARTNAME;
 907                         $this->mTitle = null;
 908
 909                         return $this->mTitle;
 910                 }
 911
 912                 $this->mTitle = $nt;
 913
 914                 return $this->mTitle;
 915         }
 916
 917         /**
 918          * Return the local file and initializes if necessary.
 919          *
 920          * @return LocalFile|UploadStashFile|null
 921          */
 922         public function getLocalFile() {
 923                 if ( is_null( $this->mLocalFile ) ) {
 924                         $nt = $this->getTitle();
 925                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 926                 }
 927
 928                 return $this->mLocalFile;
 929         }
 930
 931         /**
 932          * If the user does not supply all necessary information in the first upload
 933          * form submission (either by accident or by design) then we may want to
 934          * stash the file temporarily, get more information, and publish the file
 935          * later.
 936          *
 937          * This method will stash a file in a temporary directory for later
 938          * processing, and save the necessary descriptive info into the database.
 939          * This method returns the file object, which also has a 'fileKey' property
 940          * which can be passed through a form or API request to find this stashed
 941          * file again.
 942          *
 943          * @param User $user
 944          * @return UploadStashFile Stashed file
 945          */
 946         public function stashFile( User $user = null ) {
 947                 // was stashSessionFile
 948                 wfProfileIn( __METHOD__ );
 949
 950                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $user );
 951                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
 952                 $this->mLocalFile = $file;
 953
 954                 wfProfileOut( __METHOD__ );
 955
 956                 return $file;
 957         }
 958
 959         /**
 960          * Stash a file in a temporary directory, returning a key which can be used
 961          * to find the file again. See stashFile().
 962          *
 963          * @return string File key
 964          */
 965         public function stashFileGetKey() {
 966                 return $this->stashFile()->getFileKey();
 967         }
 968
 969         /**
 970          * alias for stashFileGetKey, for backwards compatibility
 971          *
 972          * @return string File key
 973          */
 974         public function stashSession() {
 975                 return $this->stashFileGetKey();
 976         }
 977
 978         /**
 979          * If we've modified the upload file we need to manually remove it
 980          * on exit to clean up.
 981          */
 982         public function cleanupTempFile() {
 983                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 984                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 985                         unlink( $this->mTempPath );
 986                 }
 987         }
 988
 989         public function getTempPath() {
 990                 return $this->mTempPath;
 991         }
 992
 993         /**
 994          * Split a file into a base name and all dot-delimited 'extensions'
 995          * on the end. Some web server configurations will fall back to
 996          * earlier pseudo-'extensions' to determine type and execute
 997          * scripts, so the blacklist needs to check them all.
 998          *
 999          * @param string $filename
1000          * @return array
1001          */
1002         public static function splitExtensions( $filename ) {
1003                 $bits = explode( '.', $filename );
1004                 $basename = array_shift( $bits );
1005
1006                 return array( $basename, $bits );
1007         }
1008
1009         /**
1010          * Perform case-insensitive match against a list of file extensions.
1011          * Returns true if the extension is in the list.
1012          *
1013          * @param string $ext
1014          * @param array $list
1015          * @return bool
1016          */
1017         public static function checkFileExtension( $ext, $list ) {
1018                 return in_array( strtolower( $ext ), $list );
1019         }
1020
1021         /**
1022          * Perform case-insensitive match against a list of file extensions.
1023          * Returns an array of matching extensions.
1024          *
1025          * @param array $ext
1026          * @param array $list
1027          * @return bool
1028          */
1029         public static function checkFileExtensionList( $ext, $list ) {
1030                 return array_intersect( array_map( 'strtolower', $ext ), $list );
1031         }
1032
1033         /**
1034          * Checks if the MIME type of the uploaded file matches the file extension.
1035          *
1036          * @param string $mime The MIME type of the uploaded file
1037          * @param string $extension The filename extension that the file is to be served with
1038          * @return bool
1039          */
1040         public static function verifyExtension( $mime, $extension ) {
1041                 $magic = MimeMagic::singleton();
1042
1043                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' ) {
1044                         if ( !$magic->isRecognizableExtension( $extension ) ) {
1045                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
1046                                         "unrecognized extension '$extension', can't verify\n" );
1047
1048                                 return true;
1049                         } else {
1050                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; " .
1051                                         "recognized extension '$extension', so probably invalid file\n" );
1052
1053                                 return false;
1054                         }
1055                 }
1056
1057                 $match = $magic->isMatchingExtension( $extension, $mime );
1058
1059                 if ( $match === null ) {
1060                         if ( $magic->getTypesForExtension( $extension ) !== null ) {
1061                                 wfDebug( __METHOD__ . ": No extension known for $mime, but we know a mime for $extension\n" );
1062
1063                                 return false;
1064                         } else {
1065                                 wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
1066
1067                                 return true;
1068                         }
1069                 } elseif ( $match === true ) {
1070                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
1071
1072                         /** @todo If it's a bitmap, make sure PHP or ImageMagick resp. can handle it! */
1073                         return true;
1074                 } else {
1075                         wfDebug( __METHOD__
1076                                 . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
1077
1078                         return false;
1079                 }
1080         }
1081
1082         /**
1083          * Heuristic for detecting files that *could* contain JavaScript instructions or
1084          * things that may look like HTML to a browser and are thus
1085          * potentially harmful. The present implementation will produce false
1086          * positives in some situations.
1087          *
1088          * @param string $file Pathname to the temporary upload file
1089          * @param string $mime The MIME type of the file
1090          * @param string $extension The extension of the file
1091          * @return bool True if the file contains something looking like embedded scripts
1092          */
1093         public static function detectScript( $file, $mime, $extension ) {
1094                 global $wgAllowTitlesInSVG;
1095                 wfProfileIn( __METHOD__ );
1096
1097                 # ugly hack: for text files, always look at the entire file.
1098                 # For binary field, just check the first K.
1099
1100                 if ( strpos( $mime, 'text/' ) === 0 ) {
1101                         $chunk = file_get_contents( $file );
1102                 } else {
1103                         $fp = fopen( $file, 'rb' );
1104                         $chunk = fread( $fp, 1024 );
1105                         fclose( $fp );
1106                 }
1107
1108                 $chunk = strtolower( $chunk );
1109
1110                 if ( !$chunk ) {
1111                         wfProfileOut( __METHOD__ );
1112
1113                         return false;
1114                 }
1115
1116                 # decode from UTF-16 if needed (could be used for obfuscation).
1117                 if ( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
1118                         $enc = 'UTF-16BE';
1119                 } elseif ( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
1120                         $enc = 'UTF-16LE';
1121                 } else {
1122                         $enc = null;
1123                 }
1124
1125                 if ( $enc ) {
1126                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
1127                 }
1128
1129                 $chunk = trim( $chunk );
1130
1131                 /** @todo FIXME: Convert from UTF-16 if necessary! */
1132                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
1133
1134                 # check for HTML doctype
1135                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
1136                         wfProfileOut( __METHOD__ );
1137
1138                         return true;
1139                 }
1140
1141                 // Some browsers will interpret obscure xml encodings as UTF-8, while
1142                 // PHP/expat will interpret the given encoding in the xml declaration (bug 47304)
1143                 if ( $extension == 'svg' || strpos( $mime, 'image/svg' ) === 0 ) {
1144                         if ( self::checkXMLEncodingMissmatch( $file ) ) {
1145                                 wfProfileOut( __METHOD__ );
1146
1147                                 return true;
1148                         }
1149                 }
1150
1151                 /**
1152                  * Internet Explorer for Windows performs some really stupid file type
1153                  * autodetection which can cause it to interpret valid image files as HTML
1154                  * and potentially execute JavaScript, creating a cross-site scripting
1155                  * attack vectors.
1156                  *
1157                  * Apple's Safari browser also performs some unsafe file type autodetection
1158                  * which can cause legitimate files to be interpreted as HTML if the
1159                  * web server is not correctly configured to send the right content-type
1160                  * (or if you're really uploading plain text and octet streams!)
1161                  *
1162                  * Returns true if IE is likely to mistake the given file for HTML.
1163                  * Also returns true if Safari would mistake the given file for HTML
1164                  * when served with a generic content-type.
1165                  */
1166                 $tags = array(
1167                         '<a href',
1168                         '<body',
1169                         '<head',
1170                         '<html', #also in safari
1171                         '<img',
1172                         '<pre',
1173                         '<script', #also in safari
1174                         '<table'
1175                 );
1176
1177                 if ( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
1178                         $tags[] = '<title';
1179                 }
1180
1181                 foreach ( $tags as $tag ) {
1182                         if ( false !== strpos( $chunk, $tag ) ) {
1183                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1184                                 wfProfileOut( __METHOD__ );
1185
1186                                 return true;
1187                         }
1188                 }
1189
1190                 /*
1191                  * look for JavaScript
1192                  */
1193
1194                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1195                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1196
1197                 # look for script-types
1198                 if ( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1199                         wfDebug( __METHOD__ . ": found script types\n" );
1200                         wfProfileOut( __METHOD__ );
1201
1202                         return true;
1203                 }
1204
1205                 # look for html-style script-urls
1206                 if ( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1207                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1208                         wfProfileOut( __METHOD__ );
1209
1210                         return true;
1211                 }
1212
1213                 # look for css-style script-urls
1214                 if ( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1215                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1216                         wfProfileOut( __METHOD__ );
1217
1218                         return true;
1219                 }
1220
1221                 wfDebug( __METHOD__ . ": no scripts found\n" );
1222                 wfProfileOut( __METHOD__ );
1223
1224                 return false;
1225         }
1226
1227         /**
1228          * Check a whitelist of xml encodings that are known not to be interpreted differently
1229          * by the server's xml parser (expat) and some common browsers.
1230          *
1231          * @param string $file Pathname to the temporary upload file
1232          * @return bool True if the file contains an encoding that could be misinterpreted
1233          */
1234         public static function checkXMLEncodingMissmatch( $file ) {
1235                 global $wgSVGMetadataCutoff;
1236                 $contents = file_get_contents( $file, false, null, -1, $wgSVGMetadataCutoff );
1237                 $encodingRegex = '!encoding[ \t\n\r]*=[ \t\n\r]*[\'"](.*?)[\'"]!si';
1238
1239                 if ( preg_match( "!<\?xml\b(.*?)\?>!si", $contents, $matches ) ) {
1240                         if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1241                                 && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1242                         ) {
1243                                 wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1244
1245                                 return true;
1246                         }
1247                 } elseif ( preg_match( "!<\?xml\b!si", $contents ) ) {
1248                         // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1249                         // bytes. There shouldn't be a legitimate reason for this to happen.
1250                         wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1251
1252                         return true;
1253                 } elseif ( substr( $contents, 0, 4 ) == "\x4C\x6F\xA7\x94" ) {
1254                         // EBCDIC encoded XML
1255                         wfDebug( __METHOD__ . ": EBCDIC Encoded XML\n" );
1256
1257                         return true;
1258                 }
1259
1260                 // It's possible the file is encoded with multi-byte encoding, so re-encode attempt to
1261                 // detect the encoding in case is specifies an encoding not whitelisted in self::$safeXmlEncodings
1262                 $attemptEncodings = array( 'UTF-16', 'UTF-16BE', 'UTF-32', 'UTF-32BE' );
1263                 foreach ( $attemptEncodings as $encoding ) {
1264                         wfSuppressWarnings();
1265                         $str = iconv( $encoding, 'UTF-8', $contents );
1266                         wfRestoreWarnings();
1267                         if ( $str != '' && preg_match( "!<\?xml\b(.*?)\?>!si", $str, $matches ) ) {
1268                                 if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1269                                         && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1270                                 ) {
1271                                         wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1272
1273                                         return true;
1274                                 }
1275                         } elseif ( $str != '' && preg_match( "!<\?xml\b!si", $str ) ) {
1276                                 // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1277                                 // bytes. There shouldn't be a legitimate reason for this to happen.
1278                                 wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1279
1280                                 return true;
1281                         }
1282                 }
1283
1284                 return false;
1285         }
1286
1287         /**
1288          * @param string $filename
1289          * @param bool $partial
1290          * @return mixed False of the file is verified (does not contain scripts), array otherwise.
1291          */
1292         protected function detectScriptInSvg( $filename, $partial ) {
1293                 $this->mSVGNSError = false;
1294                 $check = new XmlTypeCheck(
1295                         $filename,
1296                         array( $this, 'checkSvgScriptCallback' ),
1297                         true,
1298                         array( 'processing_instruction_handler' => 'UploadBase::checkSvgPICallback' )
1299                 );
1300                 if ( $check->wellFormed !== true ) {
1301                         // Invalid xml (bug 58553)
1302                         // But only when non-partial (bug 65724)
1303                         return $partial ? false : array( 'uploadinvalidxml' );
1304                 } elseif ( $check->filterMatch ) {
1305                         if ( $this->mSVGNSError ) {
1306                                 return array( 'uploadscriptednamespace', $this->mSVGNSError );
1307                         }
1308
1309                         return array( 'uploadscripted' );
1310                 }
1311
1312                 return false;
1313         }
1314
1315         /**
1316          * Callback to filter SVG Processing Instructions.
1317          * @param string $target Processing instruction name
1318          * @param string $data Processing instruction attribute and value
1319          * @return bool (true if the filter identified something bad)
1320          */
1321         public static function checkSvgPICallback( $target, $data ) {
1322                 // Don't allow external stylesheets (bug 57550)
1323                 if ( preg_match( '/xml-stylesheet/i', $target ) ) {
1324                         return true;
1325                 }
1326
1327                 return false;
1328         }
1329
1330         /**
1331          * @todo Replace this with a whitelist filter!
1332          * @param string $element
1333          * @param array $attribs
1334          * @return bool
1335          */
1336         public function checkSvgScriptCallback( $element, $attribs, $data = null ) {
1337
1338                 list( $namespace, $strippedElement ) = $this->splitXmlNamespace( $element );
1339
1340                 // We specifically don't include:
1341                 // http://www.w3.org/1999/xhtml (bug 60771)
1342                 static $validNamespaces = array(
1343                         '',
1344                         'adobe:ns:meta/',
1345                         'http://creativecommons.org/ns#',
1346                         'http://inkscape.sourceforge.net/dtd/sodipodi-0.dtd',
1347                         'http://ns.adobe.com/adobeillustrator/10.0/',
1348                         'http://ns.adobe.com/adobesvgviewerextensions/3.0/',
1349                         'http://ns.adobe.com/extensibility/1.0/',
1350                         'http://ns.adobe.com/flows/1.0/',
1351                         'http://ns.adobe.com/illustrator/1.0/',
1352                         'http://ns.adobe.com/imagereplacement/1.0/',
1353                         'http://ns.adobe.com/pdf/1.3/',
1354                         'http://ns.adobe.com/photoshop/1.0/',
1355                         'http://ns.adobe.com/saveforweb/1.0/',
1356                         'http://ns.adobe.com/variables/1.0/',
1357                         'http://ns.adobe.com/xap/1.0/',
1358                         'http://ns.adobe.com/xap/1.0/g/',
1359                         'http://ns.adobe.com/xap/1.0/g/img/',
1360                         'http://ns.adobe.com/xap/1.0/mm/',
1361                         'http://ns.adobe.com/xap/1.0/rights/',
1362                         'http://ns.adobe.com/xap/1.0/stype/dimensions#',
1363                         'http://ns.adobe.com/xap/1.0/stype/font#',
1364                         'http://ns.adobe.com/xap/1.0/stype/manifestitem#',
1365                         'http://ns.adobe.com/xap/1.0/stype/resourceevent#',
1366                         'http://ns.adobe.com/xap/1.0/stype/resourceref#',
1367                         'http://ns.adobe.com/xap/1.0/t/pg/',
1368                         'http://purl.org/dc/elements/1.1/',
1369                         'http://purl.org/dc/elements/1.1',
1370                         'http://schemas.microsoft.com/visio/2003/svgextensions/',
1371                         'http://sodipodi.sourceforge.net/dtd/sodipodi-0.dtd',
1372                         'http://taptrix.com/inkpad/svg_extensions',
1373                         'http://web.resource.org/cc/',
1374                         'http://www.freesoftware.fsf.org/bkchem/cdml',
1375                         'http://www.inkscape.org/namespaces/inkscape',
1376                         'http://www.opengis.net/gml',
1377                         'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
1378                         'http://www.w3.org/2000/svg',
1379                         'http://www.w3.org/tr/rec-rdf-syntax/',
1380                 );
1381
1382                 if ( !in_array( $namespace, $validNamespaces ) ) {
1383                         wfDebug( __METHOD__ . ": Non-svg namespace '$namespace' in uploaded file.\n" );
1384                         /** @todo Return a status object to a closure in XmlTypeCheck, for MW1.21+ */
1385                         $this->mSVGNSError = $namespace;
1386
1387                         return true;
1388                 }
1389
1390                 /*
1391                  * check for elements that can contain javascript
1392                  */
1393                 if ( $strippedElement == 'script' ) {
1394                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1395
1396                         return true;
1397                 }
1398
1399                 # e.g., <svg xmlns="http://www.w3.org/2000/svg">
1400                 #  <handler xmlns:ev="http://www.w3.org/2001/xml-events" ev:event="load">alert(1)</handler> </svg>
1401                 if ( $strippedElement == 'handler' ) {
1402                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1403
1404                         return true;
1405                 }
1406
1407                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1408                 if ( $strippedElement == 'stylesheet' ) {
1409                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1410
1411                         return true;
1412                 }
1413
1414                 # Block iframes, in case they pass the namespace check
1415                 if ( $strippedElement == 'iframe' ) {
1416                         wfDebug( __METHOD__ . ": iframe in uploaded file.\n" );
1417
1418                         return true;
1419                 }
1420
1421                 # Check <style> css
1422                 if ( $strippedElement == 'style'
1423                         && self::checkCssFragment( Sanitizer::normalizeCss( $data ) )
1424                 ) {
1425                         wfDebug( __METHOD__ . ": hostile css in style element.\n" );
1426                         return true;
1427                 }
1428
1429                 foreach ( $attribs as $attrib => $value ) {
1430                         $stripped = $this->stripXmlNamespace( $attrib );
1431                         $value = strtolower( $value );
1432
1433                         if ( substr( $stripped, 0, 2 ) == 'on' ) {
1434                                 wfDebug( __METHOD__
1435                                         . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1436
1437                                 return true;
1438                         }
1439
1440                         # href with non-local target (don't allow http://, javascript:, etc)
1441                         if ( $stripped == 'href'
1442                                 && strpos( $value, 'data:' ) !== 0
1443                                 && strpos( $value, '#' ) !== 0
1444                         ) {
1445                                 if ( !( $strippedElement === 'a'
1446                                         && preg_match( '!^https?://!im', $value ) )
1447                                 ) {
1448                                         wfDebug( __METHOD__ . ": Found href attribute <$strippedElement "
1449                                                 . "'$attrib'='$value' in uploaded file.\n" );
1450
1451                                         return true;
1452                                 }
1453                         }
1454
1455                         # href with embedded svg as target
1456                         if ( $stripped == 'href' && preg_match( '!data:[^,]*image/svg[^,]*,!sim', $value ) ) {
1457                                 wfDebug( __METHOD__ . ": Found href to embedded svg "
1458                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1459
1460                                 return true;
1461                         }
1462
1463                         # href with embedded (text/xml) svg as target
1464                         if ( $stripped == 'href' && preg_match( '!data:[^,]*text/xml[^,]*,!sim', $value ) ) {
1465                                 wfDebug( __METHOD__ . ": Found href to embedded svg "
1466                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1467
1468                                 return true;
1469                         }
1470
1471                         # Change href with animate from (http://html5sec.org/#137). This doesn't seem
1472                         # possible without embedding the svg, but filter here in case.
1473                         if ( $stripped == 'from'
1474                                 && $strippedElement === 'animate'
1475                                 && !preg_match( '!^https?://!im', $value )
1476                         ) {
1477                                 wfDebug( __METHOD__ . ": Found animate that might be changing href using from "
1478                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1479
1480                                 return true;
1481                         }
1482
1483                         # use set/animate to add event-handler attribute to parent
1484                         if ( ( $strippedElement == 'set' || $strippedElement == 'animate' )
1485                                 && $stripped == 'attributename'
1486                                 && substr( $value, 0, 2 ) == 'on'
1487                         ) {
1488                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with "
1489                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1490
1491                                 return true;
1492                         }
1493
1494                         # use set to add href attribute to parent element
1495                         if ( $strippedElement == 'set'
1496                                 && $stripped == 'attributename'
1497                                 && strpos( $value, 'href' ) !== false
1498                         ) {
1499                                 wfDebug( __METHOD__ . ": Found svg setting href attribute '$value' in uploaded file.\n" );
1500
1501                                 return true;
1502                         }
1503
1504                         # use set to add a remote / data / script target to an element
1505                         if ( $strippedElement == 'set'
1506                                 && $stripped == 'to'
1507                                 && preg_match( '!(http|https|data|script):!sim', $value )
1508                         ) {
1509                                 wfDebug( __METHOD__ . ": Found svg setting attribute to '$value' in uploaded file.\n" );
1510
1511                                 return true;
1512                         }
1513
1514                         # use handler attribute with remote / data / script
1515                         if ( $stripped == 'handler' && preg_match( '!(http|https|data|script):!sim', $value ) ) {
1516                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script "
1517                                         . "'$attrib'='$value' in uploaded file.\n" );
1518
1519                                 return true;
1520                         }
1521
1522                         # use CSS styles to bring in remote code
1523                         if ( $stripped == 'style'
1524                                 && self::checkCssFragment( Sanitizer::normalizeCss( $value ) )
1525                         ) {
1526                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1527                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1528                                 return true;
1529                         }
1530
1531                         # Several attributes can include css, css character escaping isn't allowed
1532                         $cssAttrs = array( 'font', 'clip-path', 'fill', 'filter', 'marker',
1533                                 'marker-end', 'marker-mid', 'marker-start', 'mask', 'stroke' );
1534                         if ( in_array( $stripped, $cssAttrs )
1535                                 && self::checkCssFragment( $value )
1536                         ) {
1537                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1538                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1539                                 return true;
1540                         }
1541
1542                         # image filters can pull in url, which could be svg that executes scripts
1543                         if ( $strippedElement == 'image'
1544                                 && $stripped == 'filter'
1545                                 && preg_match( '!url\s*\(!sim', $value )
1546                         ) {
1547                                 wfDebug( __METHOD__ . ": Found image filter with url: "
1548                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1549
1550                                 return true;
1551                         }
1552                 }
1553
1554                 return false; //No scripts detected
1555         }
1556
1557         /**
1558          * Check a block of CSS or CSS fragment for anything that looks like
1559          * it is bringing in remote code.
1560          * @param string $value a string of CSS
1561          * @param bool $propOnly only check css properties (start regex with :)
1562          * @return bool true if the CSS contains an illegal string, false if otherwise
1563          */
1564         private static function checkCssFragment( $value ) {
1565
1566                 # Forbid external stylesheets, for both reliability and to protect viewer's privacy
1567                 if ( strpos( $value, '@import' ) !== false ) {
1568                         return true;
1569                 }
1570
1571                 # We allow @font-face to embed fonts with data: urls, so we snip the string
1572                 # 'url' out so this case won't match when we check for urls below
1573                 $pattern = '!(@font-face\s*{[^}]*src:)url(\("data:;base64,)!im';
1574                 $value = preg_replace( $pattern, '$1$2', $value );
1575
1576                 # Check for remote and executable CSS. Unlike in Sanitizer::checkCss, the CSS
1577                 # properties filter and accelerator don't seem to be useful for xss in SVG files.
1578                 # Expression and -o-link don't seem to work either, but filtering them here in case.
1579                 # Additionally, we catch remote urls like url("http:..., url('http:..., url(http:...,
1580                 # but not local ones such as url("#..., url('#..., url(#....
1581                 if ( preg_match( '!expression
1582                                 | -o-link\s*:
1583                                 | -o-link-source\s*:
1584                                 | -o-replace\s*:!imx', $value ) ) {
1585                         return true;
1586                 }
1587
1588                 if ( preg_match_all(
1589                                 "!(\s*(url|image|image-set)\s*\(\s*[\"']?\s*[^#]+.*?\))!sim",
1590                                 $value,
1591                                 $matches
1592                         ) !== 0
1593                 ) {
1594                         # TODO: redo this in one regex. Until then, url("#whatever") matches the first
1595                         foreach ( $matches[1] as $match ) {
1596                                 if ( !preg_match( "!\s*(url|image|image-set)\s*\(\s*(#|'#|\"#)!im", $match ) ) {
1597                                         return true;
1598                                 }
1599                         }
1600                 }
1601
1602                 if ( preg_match( '/[\000-\010\013\016-\037\177]/', $value ) ) {
1603                         return true;
1604                 }
1605
1606                 return false;
1607         }
1608
1609         /**
1610          * Divide the element name passed by the xml parser to the callback into URI and prifix.
1611          * @param string $element
1612          * @return array Containing the namespace URI and prefix
1613          */
1614         private static function splitXmlNamespace( $element ) {
1615                 // 'http://www.w3.org/2000/svg:script' -> array( 'http://www.w3.org/2000/svg', 'script' )
1616                 $parts = explode( ':', strtolower( $element ) );
1617                 $name = array_pop( $parts );
1618                 $ns = implode( ':', $parts );
1619
1620                 return array( $ns, $name );
1621         }
1622
1623         /**
1624          * @param string $name
1625          * @return string
1626          */
1627         private function stripXmlNamespace( $name ) {
1628                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1629                 $parts = explode( ':', strtolower( $name ) );
1630
1631                 return array_pop( $parts );
1632         }
1633
1634         /**
1635          * Generic wrapper function for a virus scanner program.
1636          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1637          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1638          *
1639          * @param string $file Pathname to the temporary upload file
1640          * @return mixed False if not virus is found, null if the scan fails or is disabled,
1641          *   or a string containing feedback from the virus scanner if a virus was found.
1642          *   If textual feedback is missing but a virus was found, this function returns true.
1643          */
1644         public static function detectVirus( $file ) {
1645                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1646                 wfProfileIn( __METHOD__ );
1647
1648                 if ( !$wgAntivirus ) {
1649                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1650                         wfProfileOut( __METHOD__ );
1651
1652                         return null;
1653                 }
1654
1655                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1656                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1657                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1658                                 array( 'virus-badscanner', $wgAntivirus ) );
1659                         wfProfileOut( __METHOD__ );
1660
1661                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1662                 }
1663
1664                 # look up scanner configuration
1665                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1666                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1667                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
1668                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
1669
1670                 if ( strpos( $command, "%f" ) === false ) {
1671                         # simple pattern: append file to scan
1672                         $command .= " " . wfEscapeShellArg( $file );
1673                 } else {
1674                         # complex pattern: replace "%f" with file to scan
1675                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
1676                 }
1677
1678                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1679
1680                 # execute virus scanner
1681                 $exitCode = false;
1682
1683                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1684                 #      that does not seem to be worth the pain.
1685                 #      Ask me (Duesentrieb) about it if it's ever needed.
1686                 $output = wfShellExecWithStderr( $command, $exitCode );
1687
1688                 # map exit code to AV_xxx constants.
1689                 $mappedCode = $exitCode;
1690                 if ( $exitCodeMap ) {
1691                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1692                                 $mappedCode = $exitCodeMap[$exitCode];
1693                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1694                                 $mappedCode = $exitCodeMap["*"];
1695                         }
1696                 }
1697
1698                 /* NB: AV_NO_VIRUS is 0 but AV_SCAN_FAILED is false,
1699                  * so we need the strict equalities === and thus can't use a switch here
1700                  */
1701                 if ( $mappedCode === AV_SCAN_FAILED ) {
1702                         # scan failed (code was mapped to false by $exitCodeMap)
1703                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1704
1705                         $output = $wgAntivirusRequired
1706                                 ? wfMessage( 'virus-scanfailed', array( $exitCode ) )->text()
1707                                 : null;
1708                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1709                         # scan failed because filetype is unknown (probably imune)
1710                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1711                         $output = null;
1712                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1713                         # no virus found
1714                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1715                         $output = false;
1716                 } else {
1717                         $output = trim( $output );
1718
1719                         if ( !$output ) {
1720                                 $output = true; #if there's no output, return true
1721                         } elseif ( $msgPattern ) {
1722                                 $groups = array();
1723                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
1724                                         if ( $groups[1] ) {
1725                                                 $output = $groups[1];
1726                                         }
1727                                 }
1728                         }
1729
1730                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1731                 }
1732
1733                 wfProfileOut( __METHOD__ );
1734
1735                 return $output;
1736         }
1737
1738         /**
1739          * Check if there's an overwrite conflict and, if so, if restrictions
1740          * forbid this user from performing the upload.
1741          *
1742          * @param User $user
1743          *
1744          * @return mixed True on success, array on failure
1745          */
1746         private function checkOverwrite( $user ) {
1747                 // First check whether the local file can be overwritten
1748                 $file = $this->getLocalFile();
1749                 if ( $file->exists() ) {
1750                         if ( !self::userCanReUpload( $user, $file ) ) {
1751                                 return array( 'fileexists-forbidden', $file->getName() );
1752                         } else {
1753                                 return true;
1754                         }
1755                 }
1756
1757                 /* Check shared conflicts: if the local file does not exist, but
1758                  * wfFindFile finds a file, it exists in a shared repository.
1759                  */
1760                 $file = wfFindFile( $this->getTitle() );
1761                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1762                         return array( 'fileexists-shared-forbidden', $file->getName() );
1763                 }
1764
1765                 return true;
1766         }
1767
1768         /**
1769          * Check if a user is the last uploader
1770          *
1771          * @param User $user
1772          * @param string $img Image name
1773          * @return bool
1774          */
1775         public static function userCanReUpload( User $user, $img ) {
1776                 if ( $user->isAllowed( 'reupload' ) ) {
1777                         return true; // non-conditional
1778                 }
1779                 if ( !$user->isAllowed( 'reupload-own' ) ) {
1780                         return false;
1781                 }
1782                 if ( is_string( $img ) ) {
1783                         $img = wfLocalFile( $img );
1784                 }
1785                 if ( !( $img instanceof LocalFile ) ) {
1786                         return false;
1787                 }
1788
1789                 return $user->getId() == $img->getUser( 'id' );
1790         }
1791
1792         /**
1793          * Helper function that does various existence checks for a file.
1794          * The following checks are performed:
1795          * - The file exists
1796          * - Article with the same name as the file exists
1797          * - File exists with normalized extension
1798          * - The file looks like a thumbnail and the original exists
1799          *
1800          * @param File $file The File object to check
1801          * @return mixed False if the file does not exists, else an array
1802          */
1803         public static function getExistsWarning( $file ) {
1804                 if ( $file->exists() ) {
1805                         return array( 'warning' => 'exists', 'file' => $file );
1806                 }
1807
1808                 if ( $file->getTitle()->getArticleID() ) {
1809                         return array( 'warning' => 'page-exists', 'file' => $file );
1810                 }
1811
1812                 if ( $file->wasDeleted() && !$file->exists() ) {
1813                         return array( 'warning' => 'was-deleted', 'file' => $file );
1814                 }
1815
1816                 if ( strpos( $file->getName(), '.' ) == false ) {
1817                         $partname = $file->getName();
1818                         $extension = '';
1819                 } else {
1820                         $n = strrpos( $file->getName(), '.' );
1821                         $extension = substr( $file->getName(), $n + 1 );
1822                         $partname = substr( $file->getName(), 0, $n );
1823                 }
1824                 $normalizedExtension = File::normalizeExtension( $extension );
1825
1826                 if ( $normalizedExtension != $extension ) {
1827                         // We're not using the normalized form of the extension.
1828                         // Normal form is lowercase, using most common of alternate
1829                         // extensions (eg 'jpg' rather than 'JPEG').
1830                         //
1831                         // Check for another file using the normalized form...
1832                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1833                         $file_lc = wfLocalFile( $nt_lc );
1834
1835                         if ( $file_lc->exists() ) {
1836                                 return array(
1837                                         'warning' => 'exists-normalized',
1838                                         'file' => $file,
1839                                         'normalizedFile' => $file_lc
1840                                 );
1841                         }
1842                 }
1843
1844                 // Check for files with the same name but a different extension
1845                 $similarFiles = RepoGroup::singleton()->getLocalRepo()->findFilesByPrefix(
1846                         "{$partname}.", 1 );
1847                 if ( count( $similarFiles ) ) {
1848                         return array(
1849                                 'warning' => 'exists-normalized',
1850                                 'file' => $file,
1851                                 'normalizedFile' => $similarFiles[0],
1852                         );
1853                 }
1854
1855                 if ( self::isThumbName( $file->getName() ) ) {
1856                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1857                         $nt_thb = Title::newFromText(
1858                                 substr( $partname, strpos( $partname, '-' ) + 1 ) . '.' . $extension,
1859                                 NS_FILE
1860                         );
1861                         $file_thb = wfLocalFile( $nt_thb );
1862                         if ( $file_thb->exists() ) {
1863                                 return array(
1864                                         'warning' => 'thumb',
1865                                         'file' => $file,
1866                                         'thumbFile' => $file_thb
1867                                 );
1868                         } else {
1869                                 // File does not exist, but we just don't like the name
1870                                 return array(
1871                                         'warning' => 'thumb-name',
1872                                         'file' => $file,
1873                                         'thumbFile' => $file_thb
1874                                 );
1875                         }
1876                 }
1877
1878                 foreach ( self::getFilenamePrefixBlacklist() as $prefix ) {
1879                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1880                                 return array(
1881                                         'warning' => 'bad-prefix',
1882                                         'file' => $file,
1883                                         'prefix' => $prefix
1884                                 );
1885                         }
1886                 }
1887
1888                 return false;
1889         }
1890
1891         /**
1892          * Helper function that checks whether the filename looks like a thumbnail
1893          * @param string $filename
1894          * @return bool
1895          */
1896         public static function isThumbName( $filename ) {
1897                 $n = strrpos( $filename, '.' );
1898                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1899
1900                 return (
1901                         substr( $partname, 3, 3 ) == 'px-' ||
1902                         substr( $partname, 2, 3 ) == 'px-'
1903                 ) &&
1904                 preg_match( "/[0-9]{2}/", substr( $partname, 0, 2 ) );
1905         }
1906
1907         /**
1908          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1909          *
1910          * @return array List of prefixes
1911          */
1912         public static function getFilenamePrefixBlacklist() {
1913                 $blacklist = array();
1914                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
1915                 if ( !$message->isDisabled() ) {
1916                         $lines = explode( "\n", $message->plain() );
1917                         foreach ( $lines as $line ) {
1918                                 // Remove comment lines
1919                                 $comment = substr( trim( $line ), 0, 1 );
1920                                 if ( $comment == '#' || $comment == '' ) {
1921                                         continue;
1922                                 }
1923                                 // Remove additional comments after a prefix
1924                                 $comment = strpos( $line, '#' );
1925                                 if ( $comment > 0 ) {
1926                                         $line = substr( $line, 0, $comment - 1 );
1927                                 }
1928                                 $blacklist[] = trim( $line );
1929                         }
1930                 }
1931
1932                 return $blacklist;
1933         }
1934
1935         /**
1936          * Gets image info about the file just uploaded.
1937          *
1938          * Also has the effect of setting metadata to be an 'indexed tag name' in
1939          * returned API result if 'metadata' was requested. Oddly, we have to pass
1940          * the "result" object down just so it can do that with the appropriate
1941          * format, presumably.
1942          *
1943          * @param ApiResult $result
1944          * @return array Image info
1945          */
1946         public function getImageInfo( $result ) {
1947                 $file = $this->getLocalFile();
1948                 /** @todo This cries out for refactoring.
1949                  *  We really want to say $file->getAllInfo(); here.
1950                  * Perhaps "info" methods should be moved into files, and the API should
1951                  * just wrap them in queries.
1952                  */
1953                 if ( $file instanceof UploadStashFile ) {
1954                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
1955                         $info = ApiQueryStashImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1956                 } else {
1957                         $imParam = ApiQueryImageInfo::getPropertyNames();
1958                         $info = ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1959                 }
1960
1961                 return $info;
1962         }
1963
1964         /**
1965          * @param array $error
1966          * @return Status
1967          */
1968         public function convertVerifyErrorToStatus( $error ) {
1969                 $code = $error['status'];
1970                 unset( $code['status'] );
1971
1972                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
1973         }
1974
1975         /**
1976          * @param null|string $forType
1977          * @return int
1978          */
1979         public static function getMaxUploadSize( $forType = null ) {
1980                 global $wgMaxUploadSize;
1981
1982                 if ( is_array( $wgMaxUploadSize ) ) {
1983                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
1984                                 return $wgMaxUploadSize[$forType];
1985                         } else {
1986                                 return $wgMaxUploadSize['*'];
1987                         }
1988                 } else {
1989                         return intval( $wgMaxUploadSize );
1990                 }
1991         }
1992
1993         /**
1994          * Get the current status of a chunked upload (used for polling)
1995          *
1996          * The value will be read from cache.
1997          *
1998          * @param User $user
1999          * @param string $statusKey
2000          * @return Status[]|bool
2001          */
2002         public static function getSessionStatus( User $user, $statusKey ) {
2003                 $key = wfMemcKey( 'uploadstatus', $user->getId() ?: md5( $user->getName() ), $statusKey );
2004
2005                 return wfGetCache( CACHE_ANYTHING )->get( $key );
2006         }
2007
2008         /**
2009          * Set the current status of a chunked upload (used for polling)
2010          *
2011          * The value will be set in cache for 1 day
2012          *
2013          * @param User $user
2014          * @param string $statusKey
2015          * @param array|bool $value
2016          * @return void
2017          */
2018         public static function setSessionStatus( User $user, $statusKey, $value ) {
2019                 $key = wfMemcKey( 'uploadstatus', $user->getId() ?: md5( $user->getName() ), $statusKey );
2020
2021                 $cache = wfGetCache( CACHE_ANYTHING );
2022                 if ( $value === false ) {
2023                         $cache->delete( $key );
2024                 } else {
2025                         $cache->set( $key, $value, 86400 );
2026                 }
2027         }
2028 }