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  * See also includes/docs/upload.txt
  35  *
  36  * @author Brion Vibber
  37  * @author Bryan Tong Minh
  38  * @author Michael Dale
  39  */
  40 abstract class UploadBase {
  41         protected $mTempPath;
  42         protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
  43         protected $mTitle = false, $mTitleError = 0;
  44         protected $mFilteredName, $mFinalExtension;
  45         protected $mLocalFile, $mFileSize, $mFileProps;
  46         protected $mBlackListedExtensions;
  47         protected $mJavaDetected;
  48
  49         const SUCCESS = 0;
  50         const OK = 0;
  51         const EMPTY_FILE = 3;
  52         const MIN_LENGTH_PARTNAME = 4;
  53         const ILLEGAL_FILENAME = 5;
  54         const OVERWRITE_EXISTING_FILE = 7; # Not used anymore; handled by verifyTitlePermissions()
  55         const FILETYPE_MISSING = 8;
  56         const FILETYPE_BADTYPE = 9;
  57         const VERIFICATION_ERROR = 10;
  58
  59         # HOOK_ABORTED is the new name of UPLOAD_VERIFICATION_ERROR
  60         const UPLOAD_VERIFICATION_ERROR = 11;
  61         const HOOK_ABORTED = 11;
  62         const FILE_TOO_LARGE = 12;
  63         const WINDOWS_NONASCII_FILENAME = 13;
  64         const FILENAME_TOO_LONG = 14;
  65
  66         /**
  67          * @param $error int
  68          * @return string
  69          */
  70         public function getVerificationErrorCode( $error ) {
  71                 $code_to_status = array(self::EMPTY_FILE => 'empty-file',
  72                                                                 self::FILE_TOO_LARGE => 'file-too-large',
  73                                                                 self::FILETYPE_MISSING => 'filetype-missing',
  74                                                                 self::FILETYPE_BADTYPE => 'filetype-banned',
  75                                                                 self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  76                                                                 self::ILLEGAL_FILENAME => 'illegal-filename',
  77                                                                 self::OVERWRITE_EXISTING_FILE => 'overwrite',
  78                                                                 self::VERIFICATION_ERROR => 'verification-error',
  79                                                                 self::HOOK_ABORTED =>  'hookaborted',
  80                                                                 self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
  81                                                                 self::FILENAME_TOO_LONG => 'filename-toolong',
  82                 );
  83                 if( isset( $code_to_status[$error] ) ) {
  84                         return $code_to_status[$error];
  85                 }
  86
  87                 return 'unknown-error';
  88         }
  89
  90         /**
  91          * Returns true if uploads are enabled.
  92          * Can be override by subclasses.
  93          * @return bool
  94          */
  95         public static function isEnabled() {
  96                 global $wgEnableUploads;
  97
  98                 if ( !$wgEnableUploads ) {
  99                         return false;
 100                 }
 101
 102                 # Check php's file_uploads setting
 103                 return wfIsHipHop() || wfIniGetBool( 'file_uploads' );
 104         }
 105
 106         /**
 107          * Returns true if the user can use this upload module or else a string
 108          * identifying the missing permission.
 109          * Can be overriden by subclasses.
 110          *
 111          * @param $user User
 112          * @return bool
 113          */
 114         public static function isAllowed( $user ) {
 115                 foreach ( array( 'upload', 'edit' ) as $permission ) {
 116                         if ( !$user->isAllowed( $permission ) ) {
 117                                 return $permission;
 118                         }
 119                 }
 120                 return true;
 121         }
 122
 123         // Upload handlers. Should probably just be a global.
 124         static $uploadHandlers = array( 'Stash', 'File', 'Url' );
 125
 126         /**
 127          * Create a form of UploadBase depending on wpSourceType and initializes it
 128          *
 129          * @param $request WebRequest
 130          * @param $type
 131          * @return null
 132          */
 133         public static function createFromRequest( &$request, $type = null ) {
 134                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 135
 136                 if( !$type ) {
 137                         return null;
 138                 }
 139
 140                 // Get the upload class
 141                 $type = ucfirst( $type );
 142
 143                 // Give hooks the chance to handle this request
 144                 $className = null;
 145                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 146                 if ( is_null( $className ) ) {
 147                         $className = 'UploadFrom' . $type;
 148                         wfDebug( __METHOD__ . ": class name: $className\n" );
 149                         if( !in_array( $type, self::$uploadHandlers ) ) {
 150                                 return null;
 151                         }
 152                 }
 153
 154                 // Check whether this upload class is enabled
 155                 if( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 156                         return null;
 157                 }
 158
 159                 // Check whether the request is valid
 160                 if( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 161                         return null;
 162                 }
 163
 164                 $handler = new $className;
 165
 166                 $handler->initializeFromRequest( $request );
 167                 return $handler;
 168         }
 169
 170         /**
 171          * Check whether a request if valid for this handler
 172          * @param $request
 173          * @return bool
 174          */
 175         public static function isValidRequest( $request ) {
 176                 return false;
 177         }
 178
 179         public function __construct() {}
 180
 181         /**
 182          * Returns the upload type. Should be overridden by child classes
 183          *
 184          * @since 1.18
 185          * @return string
 186          */
 187         public function getSourceType() { return null; }
 188
 189         /**
 190          * Initialize the path information
 191          * @param $name string the desired destination name
 192          * @param $tempPath string the temporary path
 193          * @param $fileSize int the file size
 194          * @param $removeTempFile bool (false) remove the temporary file?
 195          * @throws MWException
 196          */
 197         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 198                 $this->mDesiredDestName = $name;
 199                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 200                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 201                 }
 202                 $this->mTempPath = $tempPath;
 203                 $this->mFileSize = $fileSize;
 204                 $this->mRemoveTempFile = $removeTempFile;
 205         }
 206
 207         /**
 208          * Initialize from a WebRequest. Override this in a subclass.
 209          */
 210         public abstract function initializeFromRequest( &$request );
 211
 212         /**
 213          * Fetch the file. Usually a no-op
 214          * @return Status
 215          */
 216         public function fetchFile() {
 217                 return Status::newGood();
 218         }
 219
 220         /**
 221          * Return true if the file is empty
 222          * @return bool
 223          */
 224         public function isEmptyFile() {
 225                 return empty( $this->mFileSize );
 226         }
 227
 228         /**
 229          * Return the file size
 230          * @return integer
 231          */
 232         public function getFileSize() {
 233                 return $this->mFileSize;
 234         }
 235
 236         /**
 237          * @param $srcPath String: the source path
 238          * @return string the real path if it was a virtual URL
 239          */
 240         function getRealPath( $srcPath ) {
 241                 wfProfileIn( __METHOD__ );
 242                 $repo = RepoGroup::singleton()->getLocalRepo();
 243                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 244                         // @TODO: just make uploads work with storage paths
 245                         // UploadFromStash loads files via virtuals URLs
 246                         $tmpFile = $repo->getLocalCopy( $srcPath );
 247                         $tmpFile->bind( $this ); // keep alive with $thumb
 248                         wfProfileOut( __METHOD__ );
 249                         return $tmpFile->getPath();
 250                 }
 251                 wfProfileOut( __METHOD__ );
 252                 return $srcPath;
 253         }
 254
 255         /**
 256          * Verify whether the upload is sane.
 257          * @return mixed self::OK or else an array with error information
 258          */
 259         public function verifyUpload() {
 260                 wfProfileIn( __METHOD__ );
 261
 262                 /**
 263                  * If there was no filename or a zero size given, give up quick.
 264                  */
 265                 if( $this->isEmptyFile() ) {
 266                         wfProfileOut( __METHOD__ );
 267                         return array( 'status' => self::EMPTY_FILE );
 268                 }
 269
 270                 /**
 271                  * Honor $wgMaxUploadSize
 272                  */
 273                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 274                 if( $this->mFileSize > $maxSize ) {
 275                         wfProfileOut( __METHOD__ );
 276                         return array(
 277                                 'status' => self::FILE_TOO_LARGE,
 278                                 'max' => $maxSize,
 279                         );
 280                 }
 281
 282                 /**
 283                  * Look at the contents of the file; if we can recognize the
 284                  * type but it's corrupt or data of the wrong type, we should
 285                  * probably not accept it.
 286                  */
 287                 $verification = $this->verifyFile();
 288                 if( $verification !== true ) {
 289                         wfProfileOut( __METHOD__ );
 290                         return array(
 291                                 'status' => self::VERIFICATION_ERROR,
 292                                 'details' => $verification
 293                         );
 294                 }
 295
 296                 /**
 297                  * Make sure this file can be created
 298                  */
 299                 $result = $this->validateName();
 300                 if( $result !== true ) {
 301                         wfProfileOut( __METHOD__ );
 302                         return $result;
 303                 }
 304
 305                 $error = '';
 306                 if( !wfRunHooks( 'UploadVerification',
 307                         array( $this->mDestName, $this->mTempPath, &$error ) ) )
 308                 {
 309                         wfProfileOut( __METHOD__ );
 310                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 311                 }
 312
 313                 wfProfileOut( __METHOD__ );
 314                 return array( 'status' => self::OK );
 315         }
 316
 317         /**
 318          * Verify that the name is valid and, if necessary, that we can overwrite
 319          *
 320          * @return mixed true if valid, otherwise and array with 'status'
 321          * and other keys
 322          **/
 323         protected function validateName() {
 324                 $nt = $this->getTitle();
 325                 if( is_null( $nt ) ) {
 326                         $result = array( 'status' => $this->mTitleError );
 327                         if( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 328                                 $result['filtered'] = $this->mFilteredName;
 329                         }
 330                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 331                                 $result['finalExt'] = $this->mFinalExtension;
 332                                 if ( count( $this->mBlackListedExtensions ) ) {
 333                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 334                                 }
 335                         }
 336                         return $result;
 337                 }
 338                 $this->mDestName = $this->getLocalFile()->getName();
 339
 340                 return true;
 341         }
 342
 343         /**
 344          * Verify the mime type
 345          *
 346          * @param $mime string representing the mime
 347          * @return mixed true if the file is verified, an array otherwise
 348          */
 349         protected function verifyMimeType( $mime ) {
 350                 global $wgVerifyMimeType;
 351                 wfProfileIn( __METHOD__ );
 352                 if ( $wgVerifyMimeType ) {
 353                         wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
 354                         global $wgMimeTypeBlacklist;
 355                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 356                                 wfProfileOut( __METHOD__ );
 357                                 return array( 'filetype-badmime', $mime );
 358                         }
 359
 360                         # XXX: Missing extension will be caught by validateName() via getTitle()
 361                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 362                                 wfProfileOut( __METHOD__ );
 363                                 return array( 'filetype-mime-mismatch', $this->mFinalExtension, $mime );
 364                         }
 365
 366                         # Check IE type
 367                         $fp = fopen( $this->mTempPath, 'rb' );
 368                         $chunk = fread( $fp, 256 );
 369                         fclose( $fp );
 370
 371                         $magic = MimeMagic::singleton();
 372                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 373                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 374                         foreach ( $ieTypes as $ieType ) {
 375                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 376                                         wfProfileOut( __METHOD__ );
 377                                         return array( 'filetype-bad-ie-mime', $ieType );
 378                                 }
 379                         }
 380                 }
 381
 382                 wfProfileOut( __METHOD__ );
 383                 return true;
 384         }
 385
 386         /**
 387          * Verifies that it's ok to include the uploaded file
 388          *
 389          * @return mixed true of the file is verified, array otherwise.
 390          */
 391         protected function verifyFile() {
 392                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 393                 wfProfileIn( __METHOD__ );
 394
 395                 # get the title, even though we are doing nothing with it, because
 396                 # we need to populate mFinalExtension
 397                 $this->getTitle();
 398
 399                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 400
 401                 # check mime type, if desired
 402                 $mime = $this->mFileProps[ 'file-mime' ];
 403                 $status = $this->verifyMimeType( $mime );
 404                 if ( $status !== true ) {
 405                         wfProfileOut( __METHOD__ );
 406                         return $status;
 407                 }
 408
 409                 # check for htmlish code and javascript
 410                 if ( !$wgDisableUploadScriptChecks ) {
 411                         if( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 412                                 wfProfileOut( __METHOD__ );
 413                                 return array( 'uploadscripted' );
 414                         }
 415                         if( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 416                                 if( $this->detectScriptInSvg( $this->mTempPath ) ) {
 417                                         wfProfileOut( __METHOD__ );
 418                                         return array( 'uploadscripted' );
 419                                 }
 420                         }
 421                 }
 422
 423                 # Check for Java applets, which if uploaded can bypass cross-site
 424                 # restrictions.
 425                 if ( !$wgAllowJavaUploads ) {
 426                         $this->mJavaDetected = false;
 427                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 428                                 array( $this, 'zipEntryCallback' ) );
 429                         if ( !$zipStatus->isOK() ) {
 430                                 $errors = $zipStatus->getErrorsArray();
 431                                 $error = reset( $errors );
 432                                 if ( $error[0] !== 'zip-wrong-format' ) {
 433                                         wfProfileOut( __METHOD__ );
 434                                         return $error;
 435                                 }
 436                         }
 437                         if ( $this->mJavaDetected ) {
 438                                 wfProfileOut( __METHOD__ );
 439                                 return array( 'uploadjava' );
 440                         }
 441                 }
 442
 443                 # Scan the uploaded file for viruses
 444                 $virus = $this->detectVirus( $this->mTempPath );
 445                 if ( $virus ) {
 446                         wfProfileOut( __METHOD__ );
 447                         return array( 'uploadvirus', $virus );
 448                 }
 449
 450                 $handler = MediaHandler::getHandler( $mime );
 451                 if ( $handler ) {
 452                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 453                         if ( !$handlerStatus->isOK() ) {
 454                                 $errors = $handlerStatus->getErrorsArray();
 455                                 wfProfileOut( __METHOD__ );
 456                                 return reset( $errors );
 457                         }
 458                 }
 459
 460                 wfRunHooks( 'UploadVerifyFile', array( $this, $mime, &$status ) );
 461                 if ( $status !== true ) {
 462                         wfProfileOut( __METHOD__ );
 463                         return $status;
 464                 }
 465
 466                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 467                 wfProfileOut( __METHOD__ );
 468                 return true;
 469         }
 470
 471         /**
 472          * Callback for ZipDirectoryReader to detect Java class files.
 473          */
 474         function zipEntryCallback( $entry ) {
 475                 $names = array( $entry['name'] );
 476
 477                 // If there is a null character, cut off the name at it, because JDK's
 478                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 479                 // were constructed which had ".class\0" followed by a string chosen to
 480                 // make the hash collide with the truncated name, that file could be
 481                 // returned in response to a request for the .class file.
 482                 $nullPos = strpos( $entry['name'], "\000" );
 483                 if ( $nullPos !== false ) {
 484                         $names[] = substr( $entry['name'], 0, $nullPos );
 485                 }
 486
 487                 // If there is a trailing slash in the file name, we have to strip it,
 488                 // because that's what ZIP_GetEntry() does.
 489                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 490                         $this->mJavaDetected = true;
 491                 }
 492         }
 493
 494         /**
 495          * Alias for verifyTitlePermissions. The function was originally 'verifyPermissions'
 496          * but that suggests it's checking the user, when it's really checking the title + user combination.
 497          * @param $user User object to verify the permissions against
 498          * @return mixed An array as returned by getUserPermissionsErrors or true
 499          *               in case the user has proper permissions.
 500          */
 501         public function verifyPermissions( $user ) {
 502                 return $this->verifyTitlePermissions( $user );
 503         }
 504
 505         /**
 506          * Check whether the user can edit, upload and create the image. This
 507          * checks only against the current title; if it returns errors, it may
 508          * very well be that another title will not give errors. Therefore
 509          * isAllowed() should be called as well for generic is-user-blocked or
 510          * can-user-upload checking.
 511          *
 512          * @param $user User object to verify the permissions against
 513          * @return mixed An array as returned by getUserPermissionsErrors or true
 514          *               in case the user has proper permissions.
 515          */
 516         public function verifyTitlePermissions( $user ) {
 517                 /**
 518                  * If the image is protected, non-sysop users won't be able
 519                  * to modify it by uploading a new revision.
 520                  */
 521                 $nt = $this->getTitle();
 522                 if( is_null( $nt ) ) {
 523                         return true;
 524                 }
 525                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 526                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 527                 if ( !$nt->exists() ) {
 528                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 529                 } else {
 530                         $permErrorsCreate = array();
 531                 }
 532                 if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 533                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 534                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 535                         return $permErrors;
 536                 }
 537
 538                 $overwriteError = $this->checkOverwrite( $user );
 539                 if ( $overwriteError !== true ) {
 540                         return array( $overwriteError );
 541                 }
 542
 543                 return true;
 544         }
 545
 546         /**
 547          * Check for non fatal problems with the file
 548          *
 549          * @return Array of warnings
 550          */
 551         public function checkWarnings() {
 552                 global $wgLang;
 553                 wfProfileIn( __METHOD__ );
 554
 555                 $warnings = array();
 556
 557                 $localFile = $this->getLocalFile();
 558                 $filename = $localFile->getName();
 559
 560                 /**
 561                  * Check whether the resulting filename is different from the desired one,
 562                  * but ignore things like ucfirst() and spaces/underscore things
 563                  */
 564                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 565                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 566
 567                 if( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 568                         $warnings['badfilename'] = $filename;
 569                 }
 570
 571                 // Check whether the file extension is on the unwanted list
 572                 global $wgCheckFileExtensions, $wgFileExtensions;
 573                 if ( $wgCheckFileExtensions ) {
 574                         if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) {
 575                                 $warnings['filetype-unwanted-type'] = array( $this->mFinalExtension,
 576                                         $wgLang->commaList( $wgFileExtensions ), count( $wgFileExtensions ) );
 577                         }
 578                 }
 579
 580                 global $wgUploadSizeWarning;
 581                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 582                         $warnings['large-file'] = $wgUploadSizeWarning;
 583                 }
 584
 585                 if ( $this->mFileSize == 0 ) {
 586                         $warnings['emptyfile'] = true;
 587                 }
 588
 589                 $exists = self::getExistsWarning( $localFile );
 590                 if( $exists !== false ) {
 591                         $warnings['exists'] = $exists;
 592                 }
 593
 594                 // Check dupes against existing files
 595                 $hash = FSFile::getSha1Base36FromPath( $this->mTempPath );
 596                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 597                 $title = $this->getTitle();
 598                 // Remove all matches against self
 599                 foreach ( $dupes as $key => $dupe ) {
 600                         if( $title->equals( $dupe->getTitle() ) ) {
 601                                 unset( $dupes[$key] );
 602                         }
 603                 }
 604                 if( $dupes ) {
 605                         $warnings['duplicate'] = $dupes;
 606                 }
 607
 608                 // Check dupes against archives
 609                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 610                 if ( $archivedImage->getID() > 0 ) {
 611                         $warnings['duplicate-archive'] = $archivedImage->getName();
 612                 }
 613
 614                 wfProfileOut( __METHOD__ );
 615                 return $warnings;
 616         }
 617
 618         /**
 619          * Really perform the upload. Stores the file in the local repo, watches
 620          * if necessary and runs the UploadComplete hook.
 621          *
 622          * @param $comment
 623          * @param $pageText
 624          * @param $watch
 625          * @param $user User
 626          *
 627          * @return Status indicating the whether the upload succeeded.
 628          */
 629         public function performUpload( $comment, $pageText, $watch, $user ) {
 630                 wfProfileIn( __METHOD__ );
 631
 632                 $status = $this->getLocalFile()->upload(
 633                         $this->mTempPath,
 634                         $comment,
 635                         $pageText,
 636                         File::DELETE_SOURCE,
 637                         $this->mFileProps,
 638                         false,
 639                         $user
 640                 );
 641
 642                 if( $status->isGood() ) {
 643                         if ( $watch ) {
 644                                 $user->addWatch( $this->getLocalFile()->getTitle() );
 645                         }
 646                         wfRunHooks( 'UploadComplete', array( &$this ) );
 647                 }
 648
 649                 wfProfileOut( __METHOD__ );
 650                 return $status;
 651         }
 652
 653         /**
 654          * Returns the title of the file to be uploaded. Sets mTitleError in case
 655          * the name was illegal.
 656          *
 657          * @return Title The title of the file or null in case the name was illegal
 658          */
 659         public function getTitle() {
 660                 if ( $this->mTitle !== false ) {
 661                         return $this->mTitle;
 662                 }
 663
 664                 /* Assume that if a user specified File:Something.jpg, this is an error
 665                  * and that the namespace prefix needs to be stripped of.
 666                  */
 667                 $title = Title::newFromText( $this->mDesiredDestName );
 668                 if ( $title && $title->getNamespace() == NS_FILE ) {
 669                         $this->mFilteredName = $title->getDBkey();
 670                 } else {
 671                         $this->mFilteredName = $this->mDesiredDestName;
 672                 }
 673
 674                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 675                 # exclamation mark, so restrict file name to 240 bytes.
 676                 if ( strlen( $this->mFilteredName ) > 240 ) {
 677                         $this->mTitleError = self::FILENAME_TOO_LONG;
 678                         return $this->mTitle = null;
 679                 }
 680
 681                 /**
 682                  * Chop off any directories in the given filename. Then
 683                  * filter out illegal characters, and try to make a legible name
 684                  * out of it. We'll strip some silently that Title would die on.
 685                  */
 686                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 687                 /* Normalize to title form before we do any further processing */
 688                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 689                 if( is_null( $nt ) ) {
 690                         $this->mTitleError = self::ILLEGAL_FILENAME;
 691                         return $this->mTitle = null;
 692                 }
 693                 $this->mFilteredName = $nt->getDBkey();
 694
 695
 696
 697                 /**
 698                  * We'll want to blacklist against *any* 'extension', and use
 699                  * only the final one for the whitelist.
 700                  */
 701                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 702
 703                 if( count( $ext ) ) {
 704                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 705                 } else {
 706                         $this->mFinalExtension = '';
 707
 708                         # No extension, try guessing one
 709                         $magic = MimeMagic::singleton();
 710                         $mime = $magic->guessMimeType( $this->mTempPath );
 711                         if ( $mime !== 'unknown/unknown' ) {
 712                                 # Get a space separated list of extensions
 713                                 $extList = $magic->getExtensionsForType( $mime );
 714                                 if ( $extList ) {
 715                                         # Set the extension to the canonical extension
 716                                         $this->mFinalExtension = strtok( $extList, ' ' );
 717
 718                                         # Fix up the other variables
 719                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 720                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 721                                         $ext = array( $this->mFinalExtension );
 722                                 }
 723                         }
 724
 725                 }
 726
 727                 /* Don't allow users to override the blacklist (check file extension) */
 728                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 729                 global $wgFileExtensions, $wgFileBlacklist;
 730
 731                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 732
 733                 if ( $this->mFinalExtension == '' ) {
 734                         $this->mTitleError = self::FILETYPE_MISSING;
 735                         return $this->mTitle = null;
 736                 } elseif ( $blackListedExtensions ||
 737                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 738                                         !$this->checkFileExtensionList( $ext, $wgFileExtensions ) ) ) {
 739                         $this->mBlackListedExtensions = $blackListedExtensions;
 740                         $this->mTitleError = self::FILETYPE_BADTYPE;
 741                         return $this->mTitle = null;
 742                 }
 743
 744                 // Windows may be broken with special characters, see bug XXX
 745                 if ( wfIsWindows() && !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() ) ) {
 746                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
 747                         return $this->mTitle = null;
 748                 }
 749
 750                 # If there was more than one "extension", reassemble the base
 751                 # filename to prevent bogus complaints about length
 752                 if( count( $ext ) > 1 ) {
 753                         for( $i = 0; $i < count( $ext ) - 1; $i++ ) {
 754                                 $partname .= '.' . $ext[$i];
 755                         }
 756                 }
 757
 758                 if( strlen( $partname ) < 1 ) {
 759                         $this->mTitleError =  self::MIN_LENGTH_PARTNAME;
 760                         return $this->mTitle = null;
 761                 }
 762
 763                 return $this->mTitle = $nt;
 764         }
 765
 766         /**
 767          * Return the local file and initializes if necessary.
 768          *
 769          * @return LocalFile|null
 770          */
 771         public function getLocalFile() {
 772                 if( is_null( $this->mLocalFile ) ) {
 773                         $nt = $this->getTitle();
 774                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 775                 }
 776                 return $this->mLocalFile;
 777         }
 778
 779         /**
 780          * If the user does not supply all necessary information in the first upload form submission (either by accident or
 781          * by design) then we may want to stash the file temporarily, get more information, and publish the file later.
 782          *
 783          * This method will stash a file in a temporary directory for later processing, and save the necessary descriptive info
 784          * into the database.
 785          * This method returns the file object, which also has a 'fileKey' property which can be passed through a form or
 786          * API request to find this stashed file again.
 787          *
 788          * @return UploadStashFile stashed file
 789          */
 790         public function stashFile() {
 791                 // was stashSessionFile
 792                 wfProfileIn( __METHOD__ );
 793
 794                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash();
 795                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
 796                 $this->mLocalFile = $file;
 797
 798                 wfProfileOut( __METHOD__ );
 799                 return $file;
 800         }
 801
 802         /**
 803          * Stash a file in a temporary directory, returning a key which can be used to find the file again. See stashFile().
 804          *
 805          * @return String: file key
 806          */
 807         public function stashFileGetKey() {
 808                 return $this->stashFile()->getFileKey();
 809         }
 810
 811         /**
 812          * alias for stashFileGetKey, for backwards compatibility
 813          *
 814          * @return String: file key
 815          */
 816         public function stashSession() {
 817                 return $this->stashFileGetKey();
 818         }
 819
 820         /**
 821          * If we've modified the upload file we need to manually remove it
 822          * on exit to clean up.
 823          */
 824         public function cleanupTempFile() {
 825                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 826                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 827                         unlink( $this->mTempPath );
 828                 }
 829         }
 830
 831         public function getTempPath() {
 832                 return $this->mTempPath;
 833         }
 834
 835         /**
 836          * Split a file into a base name and all dot-delimited 'extensions'
 837          * on the end. Some web server configurations will fall back to
 838          * earlier pseudo-'extensions' to determine type and execute
 839          * scripts, so the blacklist needs to check them all.
 840          *
 841          * @param $filename string
 842          * @return array
 843          */
 844         public static function splitExtensions( $filename ) {
 845                 $bits = explode( '.', $filename );
 846                 $basename = array_shift( $bits );
 847                 return array( $basename, $bits );
 848         }
 849
 850         /**
 851          * Perform case-insensitive match against a list of file extensions.
 852          * Returns true if the extension is in the list.
 853          *
 854          * @param $ext String
 855          * @param $list Array
 856          * @return Boolean
 857          */
 858         public static function checkFileExtension( $ext, $list ) {
 859                 return in_array( strtolower( $ext ), $list );
 860         }
 861
 862         /**
 863          * Perform case-insensitive match against a list of file extensions.
 864          * Returns an array of matching extensions.
 865          *
 866          * @param $ext Array
 867          * @param $list Array
 868          * @return Boolean
 869          */
 870         public static function checkFileExtensionList( $ext, $list ) {
 871                 return array_intersect( array_map( 'strtolower', $ext ), $list );
 872         }
 873
 874         /**
 875          * Checks if the mime type of the uploaded file matches the file extension.
 876          *
 877          * @param $mime String: the mime type of the uploaded file
 878          * @param $extension String: the filename extension that the file is to be served with
 879          * @return Boolean
 880          */
 881         public static function verifyExtension( $mime, $extension ) {
 882                 $magic = MimeMagic::singleton();
 883
 884                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 885                         if ( !$magic->isRecognizableExtension( $extension ) ) {
 886                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
 887                                         "unrecognized extension '$extension', can't verify\n" );
 888                                 return true;
 889                         } else {
 890                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; ".
 891                                         "recognized extension '$extension', so probably invalid file\n" );
 892                                 return false;
 893                         }
 894
 895                 $match = $magic->isMatchingExtension( $extension, $mime );
 896
 897                 if ( $match === null ) {
 898                         wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
 899                         return true;
 900                 } elseif( $match === true ) {
 901                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
 902
 903                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 904                         return true;
 905
 906                 } else {
 907                         wfDebug( __METHOD__ . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
 908                         return false;
 909                 }
 910         }
 911
 912         /**
 913          * Heuristic for detecting files that *could* contain JavaScript instructions or
 914          * things that may look like HTML to a browser and are thus
 915          * potentially harmful. The present implementation will produce false
 916          * positives in some situations.
 917          *
 918          * @param $file String: pathname to the temporary upload file
 919          * @param $mime String: the mime type of the file
 920          * @param $extension String: the extension of the file
 921          * @return Boolean: true if the file contains something looking like embedded scripts
 922          */
 923         public static function detectScript( $file, $mime, $extension ) {
 924                 global $wgAllowTitlesInSVG;
 925                 wfProfileIn( __METHOD__ );
 926
 927                 # ugly hack: for text files, always look at the entire file.
 928                 # For binary field, just check the first K.
 929
 930                 if( strpos( $mime,'text/' ) === 0 ) {
 931                         $chunk = file_get_contents( $file );
 932                 } else {
 933                         $fp = fopen( $file, 'rb' );
 934                         $chunk = fread( $fp, 1024 );
 935                         fclose( $fp );
 936                 }
 937
 938                 $chunk = strtolower( $chunk );
 939
 940                 if( !$chunk ) {
 941                         wfProfileOut( __METHOD__ );
 942                         return false;
 943                 }
 944
 945                 # decode from UTF-16 if needed (could be used for obfuscation).
 946                 if( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
 947                         $enc = 'UTF-16BE';
 948                 } elseif( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
 949                         $enc = 'UTF-16LE';
 950                 } else {
 951                         $enc = null;
 952                 }
 953
 954                 if( $enc ) {
 955                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
 956                 }
 957
 958                 $chunk = trim( $chunk );
 959
 960                 # @todo FIXME: Convert from UTF-16 if necessarry!
 961                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
 962
 963                 # check for HTML doctype
 964                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
 965                         wfProfileOut( __METHOD__ );
 966                         return true;
 967                 }
 968
 969                 /**
 970                  * Internet Explorer for Windows performs some really stupid file type
 971                  * autodetection which can cause it to interpret valid image files as HTML
 972                  * and potentially execute JavaScript, creating a cross-site scripting
 973                  * attack vectors.
 974                  *
 975                  * Apple's Safari browser also performs some unsafe file type autodetection
 976                  * which can cause legitimate files to be interpreted as HTML if the
 977                  * web server is not correctly configured to send the right content-type
 978                  * (or if you're really uploading plain text and octet streams!)
 979                  *
 980                  * Returns true if IE is likely to mistake the given file for HTML.
 981                  * Also returns true if Safari would mistake the given file for HTML
 982                  * when served with a generic content-type.
 983                  */
 984                 $tags = array(
 985                         '<a href',
 986                         '<body',
 987                         '<head',
 988                         '<html',   #also in safari
 989                         '<img',
 990                         '<pre',
 991                         '<script', #also in safari
 992                         '<table'
 993                 );
 994
 995                 if( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
 996                         $tags[] = '<title';
 997                 }
 998
 999                 foreach( $tags as $tag ) {
1000                         if( false !== strpos( $chunk, $tag ) ) {
1001                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1002                                 wfProfileOut( __METHOD__ );
1003                                 return true;
1004                         }
1005                 }
1006
1007                 /*
1008                  * look for JavaScript
1009                  */
1010
1011                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1012                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1013
1014                 # look for script-types
1015                 if( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1016                         wfDebug( __METHOD__ . ": found script types\n" );
1017                         wfProfileOut( __METHOD__ );
1018                         return true;
1019                 }
1020
1021                 # look for html-style script-urls
1022                 if( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1023                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1024                         wfProfileOut( __METHOD__ );
1025                         return true;
1026                 }
1027
1028                 # look for css-style script-urls
1029                 if( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1030                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1031                         wfProfileOut( __METHOD__ );
1032                         return true;
1033                 }
1034
1035                 wfDebug( __METHOD__ . ": no scripts found\n" );
1036                 wfProfileOut( __METHOD__ );
1037                 return false;
1038         }
1039
1040         /**
1041          * @param $filename string
1042          * @return bool
1043          */
1044         protected function detectScriptInSvg( $filename ) {
1045                 $check = new XmlTypeCheck( $filename, array( $this, 'checkSvgScriptCallback' ) );
1046                 return $check->filterMatch;
1047         }
1048
1049         /**
1050          * @todo Replace this with a whitelist filter!
1051          * @param $element string
1052          * @param $attribs array
1053          * @return bool
1054          */
1055         public function checkSvgScriptCallback( $element, $attribs ) {
1056                 $strippedElement = $this->stripXmlNamespace( $element );
1057
1058                 /*
1059                  * check for elements that can contain javascript
1060                  */
1061                 if( $strippedElement == 'script' ) {
1062                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1063                         return true;
1064                 }
1065
1066                 # e.g., <svg xmlns="http://www.w3.org/2000/svg"> <handler xmlns:ev="http://www.w3.org/2001/xml-events" ev:event="load">alert(1)</handler> </svg>
1067                 if( $strippedElement == 'handler' ) {
1068                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1069                         return true;
1070                 }
1071
1072                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1073                 if( $strippedElement == 'stylesheet' ) {
1074                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1075                         return true;
1076                 }
1077
1078                 foreach( $attribs as $attrib => $value ) {
1079                         $stripped = $this->stripXmlNamespace( $attrib );
1080                         $value = strtolower($value);
1081
1082                         if( substr( $stripped, 0, 2 ) == 'on' ) {
1083                                 wfDebug( __METHOD__ . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1084                                 return true;
1085                         }
1086
1087                         # href with javascript target
1088                         if( $stripped == 'href' && strpos( strtolower( $value ), 'javascript:' ) !== false ) {
1089                                 wfDebug( __METHOD__ . ": Found script in href attribute '$attrib'='$value' in uploaded file.\n" );
1090                                 return true;
1091                         }
1092
1093                         # href with embeded svg as target
1094                         if( $stripped == 'href' && preg_match( '!data:[^,]*image/svg[^,]*,!sim', $value ) ) {
1095                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1096                                 return true;
1097                         }
1098
1099                         # href with embeded (text/xml) svg as target
1100                         if( $stripped == 'href' && preg_match( '!data:[^,]*text/xml[^,]*,!sim', $value ) ) {
1101                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1102                                 return true;
1103                         }
1104
1105                         # use set/animate to add event-handler attribute to parent
1106                         if( ( $strippedElement == 'set' || $strippedElement == 'animate' ) && $stripped == 'attributename' && substr( $value, 0, 2 ) == 'on' ) {
1107                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1108                                 return true;
1109                         }
1110
1111                         # use set to add href attribute to parent element
1112                         if( $strippedElement == 'set' && $stripped == 'attributename' && strpos( $value, 'href' ) !== false ) {
1113                                 wfDebug( __METHOD__ . ": Found svg setting href attibute '$value' in uploaded file.\n" );
1114                                 return true;
1115                         }
1116
1117                         # use set to add a remote / data / script target to an element
1118                         if( $strippedElement == 'set' && $stripped == 'to' &&  preg_match( '!(http|https|data|script):!sim', $value ) ) {
1119                                 wfDebug( __METHOD__ . ": Found svg setting attibute to '$value' in uploaded file.\n" );
1120                                 return true;
1121                         }
1122
1123
1124                         # use handler attribute with remote / data / script
1125                         if( $stripped == 'handler' &&  preg_match( '!(http|https|data|script):!sim', $value ) ) {
1126                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script '$attrib'='$value' in uploaded file.\n" );
1127                                 return true;
1128                         }
1129
1130                         # use CSS styles to bring in remote code
1131                         # catch url("http:..., url('http:..., url(http:..., but not url("#..., url('#..., url(#....
1132                         if( $stripped == 'style' && preg_match_all( '!((?:font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke)\s*:\s*url\s*\(\s*["\']?\s*[^#]+.*?\))!sim', $value, $matches ) ) {
1133                                 foreach ($matches[1] as $match) {
1134                                         if (!preg_match( '!(?:font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke)\s*:\s*url\s*\(\s*(#|\'#|"#)!sim', $match ) ) {
1135                                                 wfDebug( __METHOD__ . ": Found svg setting a style with remote url '$attrib'='$value' in uploaded file.\n" );
1136                                                 return true;
1137                                         }
1138                                 }
1139                         }
1140
1141                         # image filters can pull in url, which could be svg that executes scripts
1142                         if( $strippedElement == 'image' && $stripped == 'filter' && preg_match( '!url\s*\(!sim', $value ) ) {
1143                                 wfDebug( __METHOD__ . ": Found image filter with url: \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1144                                 return true;
1145                         }
1146
1147                 }
1148
1149                 return false; //No scripts detected
1150         }
1151
1152         /**
1153          * @param $name string
1154          * @return string
1155          */
1156         private function stripXmlNamespace( $name ) {
1157                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1158                 $parts = explode( ':', strtolower( $name ) );
1159                 return array_pop( $parts );
1160         }
1161
1162         /**
1163          * Generic wrapper function for a virus scanner program.
1164          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1165          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1166          *
1167          * @param $file String: pathname to the temporary upload file
1168          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
1169          *         or a string containing feedback from the virus scanner if a virus was found.
1170          *         If textual feedback is missing but a virus was found, this function returns true.
1171          */
1172         public static function detectVirus( $file ) {
1173                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1174                 wfProfileIn( __METHOD__ );
1175
1176                 if ( !$wgAntivirus ) {
1177                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1178                         wfProfileOut( __METHOD__ );
1179                         return null;
1180                 }
1181
1182                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1183                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1184                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1185                                 array( 'virus-badscanner', $wgAntivirus ) );
1186                         wfProfileOut( __METHOD__ );
1187                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1188                 }
1189
1190                 # look up scanner configuration
1191                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1192                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1193                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
1194                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
1195
1196                 if ( strpos( $command, "%f" ) === false ) {
1197                         # simple pattern: append file to scan
1198                         $command .= " " . wfEscapeShellArg( $file );
1199                 } else {
1200                         # complex pattern: replace "%f" with file to scan
1201                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
1202                 }
1203
1204                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1205
1206                 # execute virus scanner
1207                 $exitCode = false;
1208
1209                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1210                 #      that does not seem to be worth the pain.
1211                 #      Ask me (Duesentrieb) about it if it's ever needed.
1212                 $output = wfShellExec( "$command 2>&1", $exitCode );
1213
1214                 # map exit code to AV_xxx constants.
1215                 $mappedCode = $exitCode;
1216                 if ( $exitCodeMap ) {
1217                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1218                                 $mappedCode = $exitCodeMap[$exitCode];
1219                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1220                                 $mappedCode = $exitCodeMap["*"];
1221                         }
1222                 }
1223
1224                 if ( $mappedCode === AV_SCAN_FAILED ) {
1225                         # scan failed (code was mapped to false by $exitCodeMap)
1226                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1227
1228                         if ( $wgAntivirusRequired ) {
1229                                 wfProfileOut( __METHOD__ );
1230                                 return wfMsg( 'virus-scanfailed', array( $exitCode ) );
1231                         } else {
1232                                 wfProfileOut( __METHOD__ );
1233                                 return null;
1234                         }
1235                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1236                         # scan failed because filetype is unknown (probably imune)
1237                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1238                         wfProfileOut( __METHOD__ );
1239                         return null;
1240                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1241                         # no virus found
1242                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1243                         wfProfileOut( __METHOD__ );
1244                         return false;
1245                 } else {
1246                         $output = trim( $output );
1247
1248                         if ( !$output ) {
1249                                 $output = true; #if there's no output, return true
1250                         } elseif ( $msgPattern ) {
1251                                 $groups = array();
1252                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
1253                                         if ( $groups[1] ) {
1254                                                 $output = $groups[1];
1255                                         }
1256                                 }
1257                         }
1258
1259                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1260                         wfProfileOut( __METHOD__ );
1261                         return $output;
1262                 }
1263         }
1264
1265         /**
1266          * Check if there's an overwrite conflict and, if so, if restrictions
1267          * forbid this user from performing the upload.
1268          *
1269          * @param $user User
1270          *
1271          * @return mixed true on success, array on failure
1272          */
1273         private function checkOverwrite( $user ) {
1274                 // First check whether the local file can be overwritten
1275                 $file = $this->getLocalFile();
1276                 if( $file->exists() ) {
1277                         if( !self::userCanReUpload( $user, $file ) ) {
1278                                 return array( 'fileexists-forbidden', $file->getName() );
1279                         } else {
1280                                 return true;
1281                         }
1282                 }
1283
1284                 /* Check shared conflicts: if the local file does not exist, but
1285                  * wfFindFile finds a file, it exists in a shared repository.
1286                  */
1287                 $file = wfFindFile( $this->getTitle() );
1288                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1289                         return array( 'fileexists-shared-forbidden', $file->getName() );
1290                 }
1291
1292                 return true;
1293         }
1294
1295         /**
1296          * Check if a user is the last uploader
1297          *
1298          * @param $user User object
1299          * @param $img String: image name
1300          * @return Boolean
1301          */
1302         public static function userCanReUpload( User $user, $img ) {
1303                 if( $user->isAllowed( 'reupload' ) ) {
1304                         return true; // non-conditional
1305                 }
1306                 if( !$user->isAllowed( 'reupload-own' ) ) {
1307                         return false;
1308                 }
1309                 if( is_string( $img ) ) {
1310                         $img = wfLocalFile( $img );
1311                 }
1312                 if ( !( $img instanceof LocalFile ) ) {
1313                         return false;
1314                 }
1315
1316                 return $user->getId() == $img->getUser( 'id' );
1317         }
1318
1319         /**
1320          * Helper function that does various existence checks for a file.
1321          * The following checks are performed:
1322          * - The file exists
1323          * - Article with the same name as the file exists
1324          * - File exists with normalized extension
1325          * - The file looks like a thumbnail and the original exists
1326          *
1327          * @param $file File The File object to check
1328          * @return mixed False if the file does not exists, else an array
1329          */
1330         public static function getExistsWarning( $file ) {
1331                 if( $file->exists() ) {
1332                         return array( 'warning' => 'exists', 'file' => $file );
1333                 }
1334
1335                 if( $file->getTitle()->getArticleID() ) {
1336                         return array( 'warning' => 'page-exists', 'file' => $file );
1337                 }
1338
1339                 if ( $file->wasDeleted() && !$file->exists() ) {
1340                         return array( 'warning' => 'was-deleted', 'file' => $file );
1341                 }
1342
1343                 if( strpos( $file->getName(), '.' ) == false ) {
1344                         $partname = $file->getName();
1345                         $extension = '';
1346                 } else {
1347                         $n = strrpos( $file->getName(), '.' );
1348                         $extension = substr( $file->getName(), $n + 1 );
1349                         $partname = substr( $file->getName(), 0, $n );
1350                 }
1351                 $normalizedExtension = File::normalizeExtension( $extension );
1352
1353                 if ( $normalizedExtension != $extension ) {
1354                         // We're not using the normalized form of the extension.
1355                         // Normal form is lowercase, using most common of alternate
1356                         // extensions (eg 'jpg' rather than 'JPEG').
1357                         //
1358                         // Check for another file using the normalized form...
1359                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1360                         $file_lc = wfLocalFile( $nt_lc );
1361
1362                         if( $file_lc->exists() ) {
1363                                 return array(
1364                                         'warning' => 'exists-normalized',
1365                                         'file' => $file,
1366                                         'normalizedFile' => $file_lc
1367                                 );
1368                         }
1369                 }
1370
1371                 if ( self::isThumbName( $file->getName() ) ) {
1372                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1373                         $nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $extension, NS_FILE );
1374                         $file_thb = wfLocalFile( $nt_thb );
1375                         if( $file_thb->exists() ) {
1376                                 return array(
1377                                         'warning' => 'thumb',
1378                                         'file' => $file,
1379                                         'thumbFile' => $file_thb
1380                                 );
1381                         } else {
1382                                 // File does not exist, but we just don't like the name
1383                                 return array(
1384                                         'warning' => 'thumb-name',
1385                                         'file' => $file,
1386                                         'thumbFile' => $file_thb
1387                                 );
1388                         }
1389                 }
1390
1391
1392                 foreach( self::getFilenamePrefixBlacklist() as $prefix ) {
1393                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1394                                 return array(
1395                                         'warning' => 'bad-prefix',
1396                                         'file' => $file,
1397                                         'prefix' => $prefix
1398                                 );
1399                         }
1400                 }
1401
1402                 return false;
1403         }
1404
1405         /**
1406          * Helper function that checks whether the filename looks like a thumbnail
1407          * @param $filename string
1408          * @return bool
1409          */
1410         public static function isThumbName( $filename ) {
1411                 $n = strrpos( $filename, '.' );
1412                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1413                 return (
1414                                         substr( $partname , 3, 3 ) == 'px-' ||
1415                                         substr( $partname , 2, 3 ) == 'px-'
1416                                 ) &&
1417                                 preg_match( "/[0-9]{2}/" , substr( $partname , 0, 2 ) );
1418         }
1419
1420         /**
1421          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1422          *
1423          * @return array list of prefixes
1424          */
1425         public static function getFilenamePrefixBlacklist() {
1426                 $blacklist = array();
1427                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
1428                 if( !$message->isDisabled() ) {
1429                         $lines = explode( "\n", $message->plain() );
1430                         foreach( $lines as $line ) {
1431                                 // Remove comment lines
1432                                 $comment = substr( trim( $line ), 0, 1 );
1433                                 if ( $comment == '#' || $comment == '' ) {
1434                                         continue;
1435                                 }
1436                                 // Remove additional comments after a prefix
1437                                 $comment = strpos( $line, '#' );
1438                                 if ( $comment > 0 ) {
1439                                         $line = substr( $line, 0, $comment-1 );
1440                                 }
1441                                 $blacklist[] = trim( $line );
1442                         }
1443                 }
1444                 return $blacklist;
1445         }
1446
1447         /**
1448          * Gets image info about the file just uploaded.
1449          *
1450          * Also has the effect of setting metadata to be an 'indexed tag name' in returned API result if
1451          * 'metadata' was requested. Oddly, we have to pass the "result" object down just so it can do that
1452          * with the appropriate format, presumably.
1453          *
1454          * @param $result ApiResult:
1455          * @return Array: image info
1456          */
1457         public function getImageInfo( $result ) {
1458                 $file = $this->getLocalFile();
1459                 // TODO This cries out for refactoring. We really want to say $file->getAllInfo(); here.
1460                 // Perhaps "info" methods should be moved into files, and the API should just wrap them in queries.
1461                 if ( $file instanceof UploadStashFile ) {
1462                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
1463                         $info = ApiQueryStashImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1464                 } else {
1465                         $imParam = ApiQueryImageInfo::getPropertyNames();
1466                         $info = ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1467                 }
1468                 return $info;
1469         }
1470
1471         /**
1472          * @param $error array
1473          * @return Status
1474          */
1475         public function convertVerifyErrorToStatus( $error ) {
1476                 $code = $error['status'];
1477                 unset( $code['status'] );
1478                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
1479         }
1480
1481         /**
1482          * @param $forType null|string
1483          * @return int
1484          */
1485         public static function getMaxUploadSize( $forType = null ) {
1486                 global $wgMaxUploadSize;
1487
1488                 if ( is_array( $wgMaxUploadSize ) ) {
1489                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
1490                                 return $wgMaxUploadSize[$forType];
1491                         } else {
1492                                 return $wgMaxUploadSize['*'];
1493                         }
1494                 } else {
1495                         return intval( $wgMaxUploadSize );
1496                 }
1497
1498         }
1499 }