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         const SESSION_STATUS_KEY = 'wsUploadStatusData';
  67
  68         /**
  69          * @param $error int
  70          * @return string
  71          */
  72         public function getVerificationErrorCode( $error ) {
  73                 $code_to_status = array(self::EMPTY_FILE => 'empty-file',
  74                                                                 self::FILE_TOO_LARGE => 'file-too-large',
  75                                                                 self::FILETYPE_MISSING => 'filetype-missing',
  76                                                                 self::FILETYPE_BADTYPE => 'filetype-banned',
  77                                                                 self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  78                                                                 self::ILLEGAL_FILENAME => 'illegal-filename',
  79                                                                 self::OVERWRITE_EXISTING_FILE => 'overwrite',
  80                                                                 self::VERIFICATION_ERROR => 'verification-error',
  81                                                                 self::HOOK_ABORTED =>  'hookaborted',
  82                                                                 self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
  83                                                                 self::FILENAME_TOO_LONG => 'filename-toolong',
  84                 );
  85                 if( isset( $code_to_status[$error] ) ) {
  86                         return $code_to_status[$error];
  87                 }
  88
  89                 return 'unknown-error';
  90         }
  91
  92         /**
  93          * Returns true if uploads are enabled.
  94          * Can be override by subclasses.
  95          * @return bool
  96          */
  97         public static function isEnabled() {
  98                 global $wgEnableUploads;
  99
 100                 if ( !$wgEnableUploads ) {
 101                         return false;
 102                 }
 103
 104                 # Check php's file_uploads setting
 105                 return wfIsHipHop() || wfIniGetBool( 'file_uploads' );
 106         }
 107
 108         /**
 109          * Returns true if the user can use this upload module or else a string
 110          * identifying the missing permission.
 111          * Can be overriden by subclasses.
 112          *
 113          * @param $user User
 114          * @return bool
 115          */
 116         public static function isAllowed( $user ) {
 117                 foreach ( array( 'upload', 'edit' ) as $permission ) {
 118                         if ( !$user->isAllowed( $permission ) ) {
 119                                 return $permission;
 120                         }
 121                 }
 122                 return true;
 123         }
 124
 125         // Upload handlers. Should probably just be a global.
 126         static $uploadHandlers = array( 'Stash', 'File', 'Url' );
 127
 128         /**
 129          * Create a form of UploadBase depending on wpSourceType and initializes it
 130          *
 131          * @param $request WebRequest
 132          * @param $type
 133          * @return null
 134          */
 135         public static function createFromRequest( &$request, $type = null ) {
 136                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 137
 138                 if( !$type ) {
 139                         return null;
 140                 }
 141
 142                 // Get the upload class
 143                 $type = ucfirst( $type );
 144
 145                 // Give hooks the chance to handle this request
 146                 $className = null;
 147                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 148                 if ( is_null( $className ) ) {
 149                         $className = 'UploadFrom' . $type;
 150                         wfDebug( __METHOD__ . ": class name: $className\n" );
 151                         if( !in_array( $type, self::$uploadHandlers ) ) {
 152                                 return null;
 153                         }
 154                 }
 155
 156                 // Check whether this upload class is enabled
 157                 if( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 158                         return null;
 159                 }
 160
 161                 // Check whether the request is valid
 162                 if( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 163                         return null;
 164                 }
 165
 166                 $handler = new $className;
 167
 168                 $handler->initializeFromRequest( $request );
 169                 return $handler;
 170         }
 171
 172         /**
 173          * Check whether a request if valid for this handler
 174          * @param $request
 175          * @return bool
 176          */
 177         public static function isValidRequest( $request ) {
 178                 return false;
 179         }
 180
 181         public function __construct() {}
 182
 183         /**
 184          * Returns the upload type. Should be overridden by child classes
 185          *
 186          * @since 1.18
 187          * @return string
 188          */
 189         public function getSourceType() { return null; }
 190
 191         /**
 192          * Initialize the path information
 193          * @param $name string the desired destination name
 194          * @param $tempPath string the temporary path
 195          * @param $fileSize int the file size
 196          * @param $removeTempFile bool (false) remove the temporary file?
 197          * @throws MWException
 198          */
 199         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 200                 $this->mDesiredDestName = $name;
 201                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 202                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 203                 }
 204                 $this->mTempPath = $tempPath;
 205                 $this->mFileSize = $fileSize;
 206                 $this->mRemoveTempFile = $removeTempFile;
 207         }
 208
 209         /**
 210          * Initialize from a WebRequest. Override this in a subclass.
 211          */
 212         public abstract function initializeFromRequest( &$request );
 213
 214         /**
 215          * Fetch the file. Usually a no-op
 216          * @return Status
 217          */
 218         public function fetchFile() {
 219                 return Status::newGood();
 220         }
 221
 222         /**
 223          * Return true if the file is empty
 224          * @return bool
 225          */
 226         public function isEmptyFile() {
 227                 return empty( $this->mFileSize );
 228         }
 229
 230         /**
 231          * Return the file size
 232          * @return integer
 233          */
 234         public function getFileSize() {
 235                 return $this->mFileSize;
 236         }
 237
 238         /**
 239          * @param $srcPath String: the source path
 240          * @return string the real path if it was a virtual URL
 241          */
 242         function getRealPath( $srcPath ) {
 243                 wfProfileIn( __METHOD__ );
 244                 $repo = RepoGroup::singleton()->getLocalRepo();
 245                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 246                         // @TODO: just make uploads work with storage paths
 247                         // UploadFromStash loads files via virtuals URLs
 248                         $tmpFile = $repo->getLocalCopy( $srcPath );
 249                         $tmpFile->bind( $this ); // keep alive with $this
 250                         wfProfileOut( __METHOD__ );
 251                         return $tmpFile->getPath();
 252                 }
 253                 wfProfileOut( __METHOD__ );
 254                 return $srcPath;
 255         }
 256
 257         /**
 258          * Verify whether the upload is sane.
 259          * @return mixed self::OK or else an array with error information
 260          */
 261         public function verifyUpload() {
 262                 wfProfileIn( __METHOD__ );
 263
 264                 /**
 265                  * If there was no filename or a zero size given, give up quick.
 266                  */
 267                 if( $this->isEmptyFile() ) {
 268                         wfProfileOut( __METHOD__ );
 269                         return array( 'status' => self::EMPTY_FILE );
 270                 }
 271
 272                 /**
 273                  * Honor $wgMaxUploadSize
 274                  */
 275                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 276                 if( $this->mFileSize > $maxSize ) {
 277                         wfProfileOut( __METHOD__ );
 278                         return array(
 279                                 'status' => self::FILE_TOO_LARGE,
 280                                 'max' => $maxSize,
 281                         );
 282                 }
 283
 284                 /**
 285                  * Look at the contents of the file; if we can recognize the
 286                  * type but it's corrupt or data of the wrong type, we should
 287                  * probably not accept it.
 288                  */
 289                 $verification = $this->verifyFile();
 290                 if( $verification !== true ) {
 291                         wfProfileOut( __METHOD__ );
 292                         return array(
 293                                 'status' => self::VERIFICATION_ERROR,
 294                                 'details' => $verification
 295                         );
 296                 }
 297
 298                 /**
 299                  * Make sure this file can be created
 300                  */
 301                 $result = $this->validateName();
 302                 if( $result !== true ) {
 303                         wfProfileOut( __METHOD__ );
 304                         return $result;
 305                 }
 306
 307                 $error = '';
 308                 if( !wfRunHooks( 'UploadVerification',
 309                         array( $this->mDestName, $this->mTempPath, &$error ) ) )
 310                 {
 311                         wfProfileOut( __METHOD__ );
 312                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 313                 }
 314
 315                 wfProfileOut( __METHOD__ );
 316                 return array( 'status' => self::OK );
 317         }
 318
 319         /**
 320          * Verify that the name is valid and, if necessary, that we can overwrite
 321          *
 322          * @return mixed true if valid, otherwise and array with 'status'
 323          * and other keys
 324          **/
 325         protected function validateName() {
 326                 $nt = $this->getTitle();
 327                 if( is_null( $nt ) ) {
 328                         $result = array( 'status' => $this->mTitleError );
 329                         if( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 330                                 $result['filtered'] = $this->mFilteredName;
 331                         }
 332                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 333                                 $result['finalExt'] = $this->mFinalExtension;
 334                                 if ( count( $this->mBlackListedExtensions ) ) {
 335                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 336                                 }
 337                         }
 338                         return $result;
 339                 }
 340                 $this->mDestName = $this->getLocalFile()->getName();
 341
 342                 return true;
 343         }
 344
 345         /**
 346          * Verify the mime type
 347          *
 348          * @param $mime string representing the mime
 349          * @return mixed true if the file is verified, an array otherwise
 350          */
 351         protected function verifyMimeType( $mime ) {
 352                 global $wgVerifyMimeType;
 353                 wfProfileIn( __METHOD__ );
 354                 if ( $wgVerifyMimeType ) {
 355                         wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
 356                         global $wgMimeTypeBlacklist;
 357                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 358                                 wfProfileOut( __METHOD__ );
 359                                 return array( 'filetype-badmime', $mime );
 360                         }
 361
 362                         # XXX: Missing extension will be caught by validateName() via getTitle()
 363                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 364                                 wfProfileOut( __METHOD__ );
 365                                 return array( 'filetype-mime-mismatch', $this->mFinalExtension, $mime );
 366                         }
 367
 368                         # Check IE type
 369                         $fp = fopen( $this->mTempPath, 'rb' );
 370                         $chunk = fread( $fp, 256 );
 371                         fclose( $fp );
 372
 373                         $magic = MimeMagic::singleton();
 374                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 375                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 376                         foreach ( $ieTypes as $ieType ) {
 377                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 378                                         wfProfileOut( __METHOD__ );
 379                                         return array( 'filetype-bad-ie-mime', $ieType );
 380                                 }
 381                         }
 382                 }
 383
 384                 wfProfileOut( __METHOD__ );
 385                 return true;
 386         }
 387
 388         /**
 389          * Verifies that it's ok to include the uploaded file
 390          *
 391          * @return mixed true of the file is verified, array otherwise.
 392          */
 393         protected function verifyFile() {
 394                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 395                 wfProfileIn( __METHOD__ );
 396
 397                 # get the title, even though we are doing nothing with it, because
 398                 # we need to populate mFinalExtension
 399                 $this->getTitle();
 400
 401                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 402
 403                 # check mime type, if desired
 404                 $mime = $this->mFileProps[ 'file-mime' ];
 405                 $status = $this->verifyMimeType( $mime );
 406                 if ( $status !== true ) {
 407                         wfProfileOut( __METHOD__ );
 408                         return $status;
 409                 }
 410
 411                 # check for htmlish code and javascript
 412                 if ( !$wgDisableUploadScriptChecks ) {
 413                         if( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 414                                 wfProfileOut( __METHOD__ );
 415                                 return array( 'uploadscripted' );
 416                         }
 417                         if( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 418                                 if( $this->detectScriptInSvg( $this->mTempPath ) ) {
 419                                         wfProfileOut( __METHOD__ );
 420                                         return array( 'uploadscripted' );
 421                                 }
 422                         }
 423                 }
 424
 425                 # Check for Java applets, which if uploaded can bypass cross-site
 426                 # restrictions.
 427                 if ( !$wgAllowJavaUploads ) {
 428                         $this->mJavaDetected = false;
 429                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 430                                 array( $this, 'zipEntryCallback' ) );
 431                         if ( !$zipStatus->isOK() ) {
 432                                 $errors = $zipStatus->getErrorsArray();
 433                                 $error = reset( $errors );
 434                                 if ( $error[0] !== 'zip-wrong-format' ) {
 435                                         wfProfileOut( __METHOD__ );
 436                                         return $error;
 437                                 }
 438                         }
 439                         if ( $this->mJavaDetected ) {
 440                                 wfProfileOut( __METHOD__ );
 441                                 return array( 'uploadjava' );
 442                         }
 443                 }
 444
 445                 # Scan the uploaded file for viruses
 446                 $virus = $this->detectVirus( $this->mTempPath );
 447                 if ( $virus ) {
 448                         wfProfileOut( __METHOD__ );
 449                         return array( 'uploadvirus', $virus );
 450                 }
 451
 452                 $handler = MediaHandler::getHandler( $mime );
 453                 if ( $handler ) {
 454                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 455                         if ( !$handlerStatus->isOK() ) {
 456                                 $errors = $handlerStatus->getErrorsArray();
 457                                 wfProfileOut( __METHOD__ );
 458                                 return reset( $errors );
 459                         }
 460                 }
 461
 462                 wfRunHooks( 'UploadVerifyFile', array( $this, $mime, &$status ) );
 463                 if ( $status !== true ) {
 464                         wfProfileOut( __METHOD__ );
 465                         return $status;
 466                 }
 467
 468                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 469                 wfProfileOut( __METHOD__ );
 470                 return true;
 471         }
 472
 473         /**
 474          * Callback for ZipDirectoryReader to detect Java class files.
 475          */
 476         function zipEntryCallback( $entry ) {
 477                 $names = array( $entry['name'] );
 478
 479                 // If there is a null character, cut off the name at it, because JDK's
 480                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 481                 // were constructed which had ".class\0" followed by a string chosen to
 482                 // make the hash collide with the truncated name, that file could be
 483                 // returned in response to a request for the .class file.
 484                 $nullPos = strpos( $entry['name'], "\000" );
 485                 if ( $nullPos !== false ) {
 486                         $names[] = substr( $entry['name'], 0, $nullPos );
 487                 }
 488
 489                 // If there is a trailing slash in the file name, we have to strip it,
 490                 // because that's what ZIP_GetEntry() does.
 491                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 492                         $this->mJavaDetected = true;
 493                 }
 494         }
 495
 496         /**
 497          * Alias for verifyTitlePermissions. The function was originally 'verifyPermissions'
 498          * but that suggests it's checking the user, when it's really checking the title + user combination.
 499          * @param $user User object to verify the permissions against
 500          * @return mixed An array as returned by getUserPermissionsErrors or true
 501          *               in case the user has proper permissions.
 502          */
 503         public function verifyPermissions( $user ) {
 504                 return $this->verifyTitlePermissions( $user );
 505         }
 506
 507         /**
 508          * Check whether the user can edit, upload and create the image. This
 509          * checks only against the current title; if it returns errors, it may
 510          * very well be that another title will not give errors. Therefore
 511          * isAllowed() should be called as well for generic is-user-blocked or
 512          * can-user-upload checking.
 513          *
 514          * @param $user User object to verify the permissions against
 515          * @return mixed An array as returned by getUserPermissionsErrors or true
 516          *               in case the user has proper permissions.
 517          */
 518         public function verifyTitlePermissions( $user ) {
 519                 /**
 520                  * If the image is protected, non-sysop users won't be able
 521                  * to modify it by uploading a new revision.
 522                  */
 523                 $nt = $this->getTitle();
 524                 if( is_null( $nt ) ) {
 525                         return true;
 526                 }
 527                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 528                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 529                 if ( !$nt->exists() ) {
 530                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 531                 } else {
 532                         $permErrorsCreate = array();
 533                 }
 534                 if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 535                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 536                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 537                         return $permErrors;
 538                 }
 539
 540                 $overwriteError = $this->checkOverwrite( $user );
 541                 if ( $overwriteError !== true ) {
 542                         return array( $overwriteError );
 543                 }
 544
 545                 return true;
 546         }
 547
 548         /**
 549          * Check for non fatal problems with the file
 550          *
 551          * @return Array of warnings
 552          */
 553         public function checkWarnings() {
 554                 global $wgLang;
 555                 wfProfileIn( __METHOD__ );
 556
 557                 $warnings = array();
 558
 559                 $localFile = $this->getLocalFile();
 560                 $filename = $localFile->getName();
 561
 562                 /**
 563                  * Check whether the resulting filename is different from the desired one,
 564                  * but ignore things like ucfirst() and spaces/underscore things
 565                  */
 566                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 567                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 568
 569                 if( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 570                         $warnings['badfilename'] = $filename;
 571                 }
 572
 573                 // Check whether the file extension is on the unwanted list
 574                 global $wgCheckFileExtensions, $wgFileExtensions;
 575                 if ( $wgCheckFileExtensions ) {
 576                         if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) {
 577                                 $warnings['filetype-unwanted-type'] = array( $this->mFinalExtension,
 578                                         $wgLang->commaList( $wgFileExtensions ), count( $wgFileExtensions ) );
 579                         }
 580                 }
 581
 582                 global $wgUploadSizeWarning;
 583                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 584                         $warnings['large-file'] = $wgUploadSizeWarning;
 585                 }
 586
 587                 if ( $this->mFileSize == 0 ) {
 588                         $warnings['emptyfile'] = true;
 589                 }
 590
 591                 $exists = self::getExistsWarning( $localFile );
 592                 if( $exists !== false ) {
 593                         $warnings['exists'] = $exists;
 594                 }
 595
 596                 // Check dupes against existing files
 597                 $hash = FSFile::getSha1Base36FromPath( $this->mTempPath );
 598                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 599                 $title = $this->getTitle();
 600                 // Remove all matches against self
 601                 foreach ( $dupes as $key => $dupe ) {
 602                         if( $title->equals( $dupe->getTitle() ) ) {
 603                                 unset( $dupes[$key] );
 604                         }
 605                 }
 606                 if( $dupes ) {
 607                         $warnings['duplicate'] = $dupes;
 608                 }
 609
 610                 // Check dupes against archives
 611                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 612                 if ( $archivedImage->getID() > 0 ) {
 613                         $warnings['duplicate-archive'] = $archivedImage->getName();
 614                 }
 615
 616                 wfProfileOut( __METHOD__ );
 617                 return $warnings;
 618         }
 619
 620         /**
 621          * Really perform the upload. Stores the file in the local repo, watches
 622          * if necessary and runs the UploadComplete hook.
 623          *
 624          * @param $comment
 625          * @param $pageText
 626          * @param $watch
 627          * @param $user User
 628          *
 629          * @return Status indicating the whether the upload succeeded.
 630          */
 631         public function performUpload( $comment, $pageText, $watch, $user ) {
 632                 wfProfileIn( __METHOD__ );
 633
 634                 $status = $this->getLocalFile()->upload(
 635                         $this->mTempPath,
 636                         $comment,
 637                         $pageText,
 638                         File::DELETE_SOURCE,
 639                         $this->mFileProps,
 640                         false,
 641                         $user
 642                 );
 643
 644                 if( $status->isGood() ) {
 645                         if ( $watch ) {
 646                                 $user->addWatch( $this->getLocalFile()->getTitle() );
 647                         }
 648                         wfRunHooks( 'UploadComplete', array( &$this ) );
 649                 }
 650
 651                 wfProfileOut( __METHOD__ );
 652                 return $status;
 653         }
 654
 655         /**
 656          * Returns the title of the file to be uploaded. Sets mTitleError in case
 657          * the name was illegal.
 658          *
 659          * @return Title The title of the file or null in case the name was illegal
 660          */
 661         public function getTitle() {
 662                 if ( $this->mTitle !== false ) {
 663                         return $this->mTitle;
 664                 }
 665
 666                 /* Assume that if a user specified File:Something.jpg, this is an error
 667                  * and that the namespace prefix needs to be stripped of.
 668                  */
 669                 $title = Title::newFromText( $this->mDesiredDestName );
 670                 if ( $title && $title->getNamespace() == NS_FILE ) {
 671                         $this->mFilteredName = $title->getDBkey();
 672                 } else {
 673                         $this->mFilteredName = $this->mDesiredDestName;
 674                 }
 675
 676                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 677                 # exclamation mark, so restrict file name to 240 bytes.
 678                 if ( strlen( $this->mFilteredName ) > 240 ) {
 679                         $this->mTitleError = self::FILENAME_TOO_LONG;
 680                         return $this->mTitle = null;
 681                 }
 682
 683                 /**
 684                  * Chop off any directories in the given filename. Then
 685                  * filter out illegal characters, and try to make a legible name
 686                  * out of it. We'll strip some silently that Title would die on.
 687                  */
 688                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 689                 /* Normalize to title form before we do any further processing */
 690                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 691                 if( is_null( $nt ) ) {
 692                         $this->mTitleError = self::ILLEGAL_FILENAME;
 693                         return $this->mTitle = null;
 694                 }
 695                 $this->mFilteredName = $nt->getDBkey();
 696
 697
 698
 699                 /**
 700                  * We'll want to blacklist against *any* 'extension', and use
 701                  * only the final one for the whitelist.
 702                  */
 703                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 704
 705                 if( count( $ext ) ) {
 706                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 707                 } else {
 708                         $this->mFinalExtension = '';
 709
 710                         # No extension, try guessing one
 711                         $magic = MimeMagic::singleton();
 712                         $mime = $magic->guessMimeType( $this->mTempPath );
 713                         if ( $mime !== 'unknown/unknown' ) {
 714                                 # Get a space separated list of extensions
 715                                 $extList = $magic->getExtensionsForType( $mime );
 716                                 if ( $extList ) {
 717                                         # Set the extension to the canonical extension
 718                                         $this->mFinalExtension = strtok( $extList, ' ' );
 719
 720                                         # Fix up the other variables
 721                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 722                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 723                                         $ext = array( $this->mFinalExtension );
 724                                 }
 725                         }
 726
 727                 }
 728
 729                 /* Don't allow users to override the blacklist (check file extension) */
 730                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 731                 global $wgFileExtensions, $wgFileBlacklist;
 732
 733                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 734
 735                 if ( $this->mFinalExtension == '' ) {
 736                         $this->mTitleError = self::FILETYPE_MISSING;
 737                         return $this->mTitle = null;
 738                 } elseif ( $blackListedExtensions ||
 739                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 740                                         !$this->checkFileExtensionList( $ext, $wgFileExtensions ) ) ) {
 741                         $this->mBlackListedExtensions = $blackListedExtensions;
 742                         $this->mTitleError = self::FILETYPE_BADTYPE;
 743                         return $this->mTitle = null;
 744                 }
 745
 746                 // Windows may be broken with special characters, see bug XXX
 747                 if ( wfIsWindows() && !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() ) ) {
 748                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
 749                         return $this->mTitle = null;
 750                 }
 751
 752                 # If there was more than one "extension", reassemble the base
 753                 # filename to prevent bogus complaints about length
 754                 if( count( $ext ) > 1 ) {
 755                         for( $i = 0; $i < count( $ext ) - 1; $i++ ) {
 756                                 $partname .= '.' . $ext[$i];
 757                         }
 758                 }
 759
 760                 if( strlen( $partname ) < 1 ) {
 761                         $this->mTitleError =  self::MIN_LENGTH_PARTNAME;
 762                         return $this->mTitle = null;
 763                 }
 764
 765                 return $this->mTitle = $nt;
 766         }
 767
 768         /**
 769          * Return the local file and initializes if necessary.
 770          *
 771          * @return LocalFile|null
 772          */
 773         public function getLocalFile() {
 774                 if( is_null( $this->mLocalFile ) ) {
 775                         $nt = $this->getTitle();
 776                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 777                 }
 778                 return $this->mLocalFile;
 779         }
 780
 781         /**
 782          * If the user does not supply all necessary information in the first upload form submission (either by accident or
 783          * by design) then we may want to stash the file temporarily, get more information, and publish the file later.
 784          *
 785          * This method will stash a file in a temporary directory for later processing, and save the necessary descriptive info
 786          * into the database.
 787          * This method returns the file object, which also has a 'fileKey' property which can be passed through a form or
 788          * API request to find this stashed file again.
 789          *
 790          * @param $user User
 791          * @return UploadStashFile stashed file
 792          */
 793         public function stashFile( User $user = null ) {
 794                 // was stashSessionFile
 795                 wfProfileIn( __METHOD__ );
 796
 797                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $user );
 798                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
 799                 $this->mLocalFile = $file;
 800
 801                 wfProfileOut( __METHOD__ );
 802                 return $file;
 803         }
 804
 805         /**
 806          * Stash a file in a temporary directory, returning a key which can be used to find the file again. See stashFile().
 807          *
 808          * @return String: file key
 809          */
 810         public function stashFileGetKey() {
 811                 return $this->stashFile()->getFileKey();
 812         }
 813
 814         /**
 815          * alias for stashFileGetKey, for backwards compatibility
 816          *
 817          * @return String: file key
 818          */
 819         public function stashSession() {
 820                 return $this->stashFileGetKey();
 821         }
 822
 823         /**
 824          * If we've modified the upload file we need to manually remove it
 825          * on exit to clean up.
 826          */
 827         public function cleanupTempFile() {
 828                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 829                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 830                         unlink( $this->mTempPath );
 831                 }
 832         }
 833
 834         public function getTempPath() {
 835                 return $this->mTempPath;
 836         }
 837
 838         /**
 839          * Split a file into a base name and all dot-delimited 'extensions'
 840          * on the end. Some web server configurations will fall back to
 841          * earlier pseudo-'extensions' to determine type and execute
 842          * scripts, so the blacklist needs to check them all.
 843          *
 844          * @param $filename string
 845          * @return array
 846          */
 847         public static function splitExtensions( $filename ) {
 848                 $bits = explode( '.', $filename );
 849                 $basename = array_shift( $bits );
 850                 return array( $basename, $bits );
 851         }
 852
 853         /**
 854          * Perform case-insensitive match against a list of file extensions.
 855          * Returns true if the extension is in the list.
 856          *
 857          * @param $ext String
 858          * @param $list Array
 859          * @return Boolean
 860          */
 861         public static function checkFileExtension( $ext, $list ) {
 862                 return in_array( strtolower( $ext ), $list );
 863         }
 864
 865         /**
 866          * Perform case-insensitive match against a list of file extensions.
 867          * Returns an array of matching extensions.
 868          *
 869          * @param $ext Array
 870          * @param $list Array
 871          * @return Boolean
 872          */
 873         public static function checkFileExtensionList( $ext, $list ) {
 874                 return array_intersect( array_map( 'strtolower', $ext ), $list );
 875         }
 876
 877         /**
 878          * Checks if the mime type of the uploaded file matches the file extension.
 879          *
 880          * @param $mime String: the mime type of the uploaded file
 881          * @param $extension String: the filename extension that the file is to be served with
 882          * @return Boolean
 883          */
 884         public static function verifyExtension( $mime, $extension ) {
 885                 $magic = MimeMagic::singleton();
 886
 887                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 888                         if ( !$magic->isRecognizableExtension( $extension ) ) {
 889                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
 890                                         "unrecognized extension '$extension', can't verify\n" );
 891                                 return true;
 892                         } else {
 893                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; ".
 894                                         "recognized extension '$extension', so probably invalid file\n" );
 895                                 return false;
 896                         }
 897
 898                 $match = $magic->isMatchingExtension( $extension, $mime );
 899
 900                 if ( $match === null ) {
 901                         wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
 902                         return true;
 903                 } elseif( $match === true ) {
 904                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
 905
 906                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 907                         return true;
 908
 909                 } else {
 910                         wfDebug( __METHOD__ . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
 911                         return false;
 912                 }
 913         }
 914
 915         /**
 916          * Heuristic for detecting files that *could* contain JavaScript instructions or
 917          * things that may look like HTML to a browser and are thus
 918          * potentially harmful. The present implementation will produce false
 919          * positives in some situations.
 920          *
 921          * @param $file String: pathname to the temporary upload file
 922          * @param $mime String: the mime type of the file
 923          * @param $extension String: the extension of the file
 924          * @return Boolean: true if the file contains something looking like embedded scripts
 925          */
 926         public static function detectScript( $file, $mime, $extension ) {
 927                 global $wgAllowTitlesInSVG;
 928                 wfProfileIn( __METHOD__ );
 929
 930                 # ugly hack: for text files, always look at the entire file.
 931                 # For binary field, just check the first K.
 932
 933                 if( strpos( $mime,'text/' ) === 0 ) {
 934                         $chunk = file_get_contents( $file );
 935                 } else {
 936                         $fp = fopen( $file, 'rb' );
 937                         $chunk = fread( $fp, 1024 );
 938                         fclose( $fp );
 939                 }
 940
 941                 $chunk = strtolower( $chunk );
 942
 943                 if( !$chunk ) {
 944                         wfProfileOut( __METHOD__ );
 945                         return false;
 946                 }
 947
 948                 # decode from UTF-16 if needed (could be used for obfuscation).
 949                 if( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
 950                         $enc = 'UTF-16BE';
 951                 } elseif( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
 952                         $enc = 'UTF-16LE';
 953                 } else {
 954                         $enc = null;
 955                 }
 956
 957                 if( $enc ) {
 958                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
 959                 }
 960
 961                 $chunk = trim( $chunk );
 962
 963                 # @todo FIXME: Convert from UTF-16 if necessarry!
 964                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
 965
 966                 # check for HTML doctype
 967                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
 968                         wfProfileOut( __METHOD__ );
 969                         return true;
 970                 }
 971
 972                 /**
 973                  * Internet Explorer for Windows performs some really stupid file type
 974                  * autodetection which can cause it to interpret valid image files as HTML
 975                  * and potentially execute JavaScript, creating a cross-site scripting
 976                  * attack vectors.
 977                  *
 978                  * Apple's Safari browser also performs some unsafe file type autodetection
 979                  * which can cause legitimate files to be interpreted as HTML if the
 980                  * web server is not correctly configured to send the right content-type
 981                  * (or if you're really uploading plain text and octet streams!)
 982                  *
 983                  * Returns true if IE is likely to mistake the given file for HTML.
 984                  * Also returns true if Safari would mistake the given file for HTML
 985                  * when served with a generic content-type.
 986                  */
 987                 $tags = array(
 988                         '<a href',
 989                         '<body',
 990                         '<head',
 991                         '<html',   #also in safari
 992                         '<img',
 993                         '<pre',
 994                         '<script', #also in safari
 995                         '<table'
 996                 );
 997
 998                 if( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
 999                         $tags[] = '<title';
1000                 }
1001
1002                 foreach( $tags as $tag ) {
1003                         if( false !== strpos( $chunk, $tag ) ) {
1004                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1005                                 wfProfileOut( __METHOD__ );
1006                                 return true;
1007                         }
1008                 }
1009
1010                 /*
1011                  * look for JavaScript
1012                  */
1013
1014                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1015                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1016
1017                 # look for script-types
1018                 if( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1019                         wfDebug( __METHOD__ . ": found script types\n" );
1020                         wfProfileOut( __METHOD__ );
1021                         return true;
1022                 }
1023
1024                 # look for html-style script-urls
1025                 if( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1026                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1027                         wfProfileOut( __METHOD__ );
1028                         return true;
1029                 }
1030
1031                 # look for css-style script-urls
1032                 if( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1033                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1034                         wfProfileOut( __METHOD__ );
1035                         return true;
1036                 }
1037
1038                 wfDebug( __METHOD__ . ": no scripts found\n" );
1039                 wfProfileOut( __METHOD__ );
1040                 return false;
1041         }
1042
1043         /**
1044          * @param $filename string
1045          * @return bool
1046          */
1047         protected function detectScriptInSvg( $filename ) {
1048                 $check = new XmlTypeCheck( $filename, array( $this, 'checkSvgScriptCallback' ) );
1049                 return $check->filterMatch;
1050         }
1051
1052         /**
1053          * @todo Replace this with a whitelist filter!
1054          * @param $element string
1055          * @param $attribs array
1056          * @return bool
1057          */
1058         public function checkSvgScriptCallback( $element, $attribs ) {
1059                 $strippedElement = $this->stripXmlNamespace( $element );
1060
1061                 /*
1062                  * check for elements that can contain javascript
1063                  */
1064                 if( $strippedElement == 'script' ) {
1065                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1066                         return true;
1067                 }
1068
1069                 # 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>
1070                 if( $strippedElement == 'handler' ) {
1071                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1072                         return true;
1073                 }
1074
1075                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1076                 if( $strippedElement == 'stylesheet' ) {
1077                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1078                         return true;
1079                 }
1080
1081                 foreach( $attribs as $attrib => $value ) {
1082                         $stripped = $this->stripXmlNamespace( $attrib );
1083                         $value = strtolower($value);
1084
1085                         if( substr( $stripped, 0, 2 ) == 'on' ) {
1086                                 wfDebug( __METHOD__ . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1087                                 return true;
1088                         }
1089
1090                         # href with javascript target
1091                         if( $stripped == 'href' && strpos( strtolower( $value ), 'javascript:' ) !== false ) {
1092                                 wfDebug( __METHOD__ . ": Found script in href attribute '$attrib'='$value' in uploaded file.\n" );
1093                                 return true;
1094                         }
1095
1096                         # href with embeded svg as target
1097                         if( $stripped == 'href' && preg_match( '!data:[^,]*image/svg[^,]*,!sim', $value ) ) {
1098                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1099                                 return true;
1100                         }
1101
1102                         # href with embeded (text/xml) svg as target
1103                         if( $stripped == 'href' && preg_match( '!data:[^,]*text/xml[^,]*,!sim', $value ) ) {
1104                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1105                                 return true;
1106                         }
1107
1108                         # use set/animate to add event-handler attribute to parent
1109                         if( ( $strippedElement == 'set' || $strippedElement == 'animate' ) && $stripped == 'attributename' && substr( $value, 0, 2 ) == 'on' ) {
1110                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1111                                 return true;
1112                         }
1113
1114                         # use set to add href attribute to parent element
1115                         if( $strippedElement == 'set' && $stripped == 'attributename' && strpos( $value, 'href' ) !== false ) {
1116                                 wfDebug( __METHOD__ . ": Found svg setting href attibute '$value' in uploaded file.\n" );
1117                                 return true;
1118                         }
1119
1120                         # use set to add a remote / data / script target to an element
1121                         if( $strippedElement == 'set' && $stripped == 'to' &&  preg_match( '!(http|https|data|script):!sim', $value ) ) {
1122                                 wfDebug( __METHOD__ . ": Found svg setting attibute to '$value' in uploaded file.\n" );
1123                                 return true;
1124                         }
1125
1126
1127                         # use handler attribute with remote / data / script
1128                         if( $stripped == 'handler' &&  preg_match( '!(http|https|data|script):!sim', $value ) ) {
1129                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script '$attrib'='$value' in uploaded file.\n" );
1130                                 return true;
1131                         }
1132
1133                         # use CSS styles to bring in remote code
1134                         # catch url("http:..., url('http:..., url(http:..., but not url("#..., url('#..., url(#....
1135                         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, $matches ) ) {
1136                                 foreach ($matches[1] as $match) {
1137                                         if (!preg_match( '!(?:font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke)\s*:\s*url\s*\(\s*(#|\'#|"#)!sim', $match ) ) {
1138                                                 wfDebug( __METHOD__ . ": Found svg setting a style with remote url '$attrib'='$value' in uploaded file.\n" );
1139                                                 return true;
1140                                         }
1141                                 }
1142                         }
1143
1144                         # image filters can pull in url, which could be svg that executes scripts
1145                         if( $strippedElement == 'image' && $stripped == 'filter' && preg_match( '!url\s*\(!sim', $value ) ) {
1146                                 wfDebug( __METHOD__ . ": Found image filter with url: \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1147                                 return true;
1148                         }
1149
1150                 }
1151
1152                 return false; //No scripts detected
1153         }
1154
1155         /**
1156          * @param $name string
1157          * @return string
1158          */
1159         private function stripXmlNamespace( $name ) {
1160                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1161                 $parts = explode( ':', strtolower( $name ) );
1162                 return array_pop( $parts );
1163         }
1164
1165         /**
1166          * Generic wrapper function for a virus scanner program.
1167          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1168          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1169          *
1170          * @param $file String: pathname to the temporary upload file
1171          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
1172          *         or a string containing feedback from the virus scanner if a virus was found.
1173          *         If textual feedback is missing but a virus was found, this function returns true.
1174          */
1175         public static function detectVirus( $file ) {
1176                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1177                 wfProfileIn( __METHOD__ );
1178
1179                 if ( !$wgAntivirus ) {
1180                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1181                         wfProfileOut( __METHOD__ );
1182                         return null;
1183                 }
1184
1185                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1186                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1187                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1188                                 array( 'virus-badscanner', $wgAntivirus ) );
1189                         wfProfileOut( __METHOD__ );
1190                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1191                 }
1192
1193                 # look up scanner configuration
1194                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1195                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1196                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
1197                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
1198
1199                 if ( strpos( $command, "%f" ) === false ) {
1200                         # simple pattern: append file to scan
1201                         $command .= " " . wfEscapeShellArg( $file );
1202                 } else {
1203                         # complex pattern: replace "%f" with file to scan
1204                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
1205                 }
1206
1207                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1208
1209                 # execute virus scanner
1210                 $exitCode = false;
1211
1212                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1213                 #      that does not seem to be worth the pain.
1214                 #      Ask me (Duesentrieb) about it if it's ever needed.
1215                 $output = wfShellExec( "$command 2>&1", $exitCode );
1216
1217                 # map exit code to AV_xxx constants.
1218                 $mappedCode = $exitCode;
1219                 if ( $exitCodeMap ) {
1220                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1221                                 $mappedCode = $exitCodeMap[$exitCode];
1222                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1223                                 $mappedCode = $exitCodeMap["*"];
1224                         }
1225                 }
1226
1227                 if ( $mappedCode === AV_SCAN_FAILED ) {
1228                         # scan failed (code was mapped to false by $exitCodeMap)
1229                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1230
1231                         if ( $wgAntivirusRequired ) {
1232                                 wfProfileOut( __METHOD__ );
1233                                 return wfMessage( 'virus-scanfailed', array( $exitCode ) )->text();
1234                         } else {
1235                                 wfProfileOut( __METHOD__ );
1236                                 return null;
1237                         }
1238                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1239                         # scan failed because filetype is unknown (probably imune)
1240                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1241                         wfProfileOut( __METHOD__ );
1242                         return null;
1243                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1244                         # no virus found
1245                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1246                         wfProfileOut( __METHOD__ );
1247                         return false;
1248                 } else {
1249                         $output = trim( $output );
1250
1251                         if ( !$output ) {
1252                                 $output = true; #if there's no output, return true
1253                         } elseif ( $msgPattern ) {
1254                                 $groups = array();
1255                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
1256                                         if ( $groups[1] ) {
1257                                                 $output = $groups[1];
1258                                         }
1259                                 }
1260                         }
1261
1262                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1263                         wfProfileOut( __METHOD__ );
1264                         return $output;
1265                 }
1266         }
1267
1268         /**
1269          * Check if there's an overwrite conflict and, if so, if restrictions
1270          * forbid this user from performing the upload.
1271          *
1272          * @param $user User
1273          *
1274          * @return mixed true on success, array on failure
1275          */
1276         private function checkOverwrite( $user ) {
1277                 // First check whether the local file can be overwritten
1278                 $file = $this->getLocalFile();
1279                 if( $file->exists() ) {
1280                         if( !self::userCanReUpload( $user, $file ) ) {
1281                                 return array( 'fileexists-forbidden', $file->getName() );
1282                         } else {
1283                                 return true;
1284                         }
1285                 }
1286
1287                 /* Check shared conflicts: if the local file does not exist, but
1288                  * wfFindFile finds a file, it exists in a shared repository.
1289                  */
1290                 $file = wfFindFile( $this->getTitle() );
1291                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1292                         return array( 'fileexists-shared-forbidden', $file->getName() );
1293                 }
1294
1295                 return true;
1296         }
1297
1298         /**
1299          * Check if a user is the last uploader
1300          *
1301          * @param $user User object
1302          * @param $img String: image name
1303          * @return Boolean
1304          */
1305         public static function userCanReUpload( User $user, $img ) {
1306                 if( $user->isAllowed( 'reupload' ) ) {
1307                         return true; // non-conditional
1308                 }
1309                 if( !$user->isAllowed( 'reupload-own' ) ) {
1310                         return false;
1311                 }
1312                 if( is_string( $img ) ) {
1313                         $img = wfLocalFile( $img );
1314                 }
1315                 if ( !( $img instanceof LocalFile ) ) {
1316                         return false;
1317                 }
1318
1319                 return $user->getId() == $img->getUser( 'id' );
1320         }
1321
1322         /**
1323          * Helper function that does various existence checks for a file.
1324          * The following checks are performed:
1325          * - The file exists
1326          * - Article with the same name as the file exists
1327          * - File exists with normalized extension
1328          * - The file looks like a thumbnail and the original exists
1329          *
1330          * @param $file File The File object to check
1331          * @return mixed False if the file does not exists, else an array
1332          */
1333         public static function getExistsWarning( $file ) {
1334                 if( $file->exists() ) {
1335                         return array( 'warning' => 'exists', 'file' => $file );
1336                 }
1337
1338                 if( $file->getTitle()->getArticleID() ) {
1339                         return array( 'warning' => 'page-exists', 'file' => $file );
1340                 }
1341
1342                 if ( $file->wasDeleted() && !$file->exists() ) {
1343                         return array( 'warning' => 'was-deleted', 'file' => $file );
1344                 }
1345
1346                 if( strpos( $file->getName(), '.' ) == false ) {
1347                         $partname = $file->getName();
1348                         $extension = '';
1349                 } else {
1350                         $n = strrpos( $file->getName(), '.' );
1351                         $extension = substr( $file->getName(), $n + 1 );
1352                         $partname = substr( $file->getName(), 0, $n );
1353                 }
1354                 $normalizedExtension = File::normalizeExtension( $extension );
1355
1356                 if ( $normalizedExtension != $extension ) {
1357                         // We're not using the normalized form of the extension.
1358                         // Normal form is lowercase, using most common of alternate
1359                         // extensions (eg 'jpg' rather than 'JPEG').
1360                         //
1361                         // Check for another file using the normalized form...
1362                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1363                         $file_lc = wfLocalFile( $nt_lc );
1364
1365                         if( $file_lc->exists() ) {
1366                                 return array(
1367                                         'warning' => 'exists-normalized',
1368                                         'file' => $file,
1369                                         'normalizedFile' => $file_lc
1370                                 );
1371                         }
1372                 }
1373
1374                 if ( self::isThumbName( $file->getName() ) ) {
1375                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1376                         $nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $extension, NS_FILE );
1377                         $file_thb = wfLocalFile( $nt_thb );
1378                         if( $file_thb->exists() ) {
1379                                 return array(
1380                                         'warning' => 'thumb',
1381                                         'file' => $file,
1382                                         'thumbFile' => $file_thb
1383                                 );
1384                         } else {
1385                                 // File does not exist, but we just don't like the name
1386                                 return array(
1387                                         'warning' => 'thumb-name',
1388                                         'file' => $file,
1389                                         'thumbFile' => $file_thb
1390                                 );
1391                         }
1392                 }
1393
1394
1395                 foreach( self::getFilenamePrefixBlacklist() as $prefix ) {
1396                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1397                                 return array(
1398                                         'warning' => 'bad-prefix',
1399                                         'file' => $file,
1400                                         'prefix' => $prefix
1401                                 );
1402                         }
1403                 }
1404
1405                 return false;
1406         }
1407
1408         /**
1409          * Helper function that checks whether the filename looks like a thumbnail
1410          * @param $filename string
1411          * @return bool
1412          */
1413         public static function isThumbName( $filename ) {
1414                 $n = strrpos( $filename, '.' );
1415                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1416                 return (
1417                                         substr( $partname , 3, 3 ) == 'px-' ||
1418                                         substr( $partname , 2, 3 ) == 'px-'
1419                                 ) &&
1420                                 preg_match( "/[0-9]{2}/" , substr( $partname , 0, 2 ) );
1421         }
1422
1423         /**
1424          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1425          *
1426          * @return array list of prefixes
1427          */
1428         public static function getFilenamePrefixBlacklist() {
1429                 $blacklist = array();
1430                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
1431                 if( !$message->isDisabled() ) {
1432                         $lines = explode( "\n", $message->plain() );
1433                         foreach( $lines as $line ) {
1434                                 // Remove comment lines
1435                                 $comment = substr( trim( $line ), 0, 1 );
1436                                 if ( $comment == '#' || $comment == '' ) {
1437                                         continue;
1438                                 }
1439                                 // Remove additional comments after a prefix
1440                                 $comment = strpos( $line, '#' );
1441                                 if ( $comment > 0 ) {
1442                                         $line = substr( $line, 0, $comment-1 );
1443                                 }
1444                                 $blacklist[] = trim( $line );
1445                         }
1446                 }
1447                 return $blacklist;
1448         }
1449
1450         /**
1451          * Gets image info about the file just uploaded.
1452          *
1453          * Also has the effect of setting metadata to be an 'indexed tag name' in returned API result if
1454          * 'metadata' was requested. Oddly, we have to pass the "result" object down just so it can do that
1455          * with the appropriate format, presumably.
1456          *
1457          * @param $result ApiResult:
1458          * @return Array: image info
1459          */
1460         public function getImageInfo( $result ) {
1461                 $file = $this->getLocalFile();
1462                 // TODO This cries out for refactoring. We really want to say $file->getAllInfo(); here.
1463                 // Perhaps "info" methods should be moved into files, and the API should just wrap them in queries.
1464                 if ( $file instanceof UploadStashFile ) {
1465                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
1466                         $info = ApiQueryStashImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1467                 } else {
1468                         $imParam = ApiQueryImageInfo::getPropertyNames();
1469                         $info = ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1470                 }
1471                 return $info;
1472         }
1473
1474         /**
1475          * @param $error array
1476          * @return Status
1477          */
1478         public function convertVerifyErrorToStatus( $error ) {
1479                 $code = $error['status'];
1480                 unset( $code['status'] );
1481                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
1482         }
1483
1484         /**
1485          * @param $forType null|string
1486          * @return int
1487          */
1488         public static function getMaxUploadSize( $forType = null ) {
1489                 global $wgMaxUploadSize;
1490
1491                 if ( is_array( $wgMaxUploadSize ) ) {
1492                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
1493                                 return $wgMaxUploadSize[$forType];
1494                         } else {
1495                                 return $wgMaxUploadSize['*'];
1496                         }
1497                 } else {
1498                         return intval( $wgMaxUploadSize );
1499                 }
1500         }
1501
1502         /**
1503          * Get the current status of a chunked upload (used for polling).
1504          * The status will be read from the *current* user session.
1505          * @param $statusKey string
1506          * @return Array|bool
1507          */
1508         public static function getSessionStatus( $statusKey ) {
1509                 return isset( $_SESSION[self::SESSION_STATUS_KEY][$statusKey] )
1510                         ? $_SESSION[self::SESSION_STATUS_KEY][$statusKey]
1511                         : false;
1512         }
1513
1514         /**
1515          * Set the current status of a chunked upload (used for polling).
1516          * The status will be stored in the *current* user session.
1517          * @param $statusKey string
1518          * @param $value array|false
1519          * @return void
1520          */
1521         public static function setSessionStatus( $statusKey, $value ) {
1522                 if ( $value === false ) {
1523                         unset( $_SESSION[self::SESSION_STATUS_KEY][$statusKey] );
1524                 } else {
1525                         $_SESSION[self::SESSION_STATUS_KEY][$statusKey] = $value;
1526                 }
1527         }
1528 }