includes/upload/UploadBase.php

   1 <?php
   2 /**
   3  * @defgroup Upload
   4  */
   5
   6 /**
   7  * @ingroup Upload
   8  *
   9  * UploadBase and subclasses are the backend of MediaWiki's file uploads.
  10  * The frontends are formed by ApiUpload and SpecialUpload.
  11  *
  12  * See also includes/docs/upload.txt
  13  *
  14  * @author Brion Vibber
  15  * @author Bryan Tong Minh
  16  * @author Michael Dale
  17  */
  18 abstract class UploadBase {
  19         protected $mTempPath;
  20         protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
  21         protected $mTitle = false, $mTitleError = 0;
  22         protected $mFilteredName, $mFinalExtension;
  23         protected $mLocalFile, $mFileSize, $mFileProps;
  24         protected $mBlackListedExtensions;
  25         protected $mJavaDetected;
  26
  27         const SUCCESS = 0;
  28         const OK = 0;
  29         const EMPTY_FILE = 3;
  30         const MIN_LENGTH_PARTNAME = 4;
  31         const ILLEGAL_FILENAME = 5;
  32         const OVERWRITE_EXISTING_FILE = 7; # Not used anymore; handled by verifyTitlePermissions()
  33         const FILETYPE_MISSING = 8;
  34         const FILETYPE_BADTYPE = 9;
  35         const VERIFICATION_ERROR = 10;
  36
  37         # HOOK_ABORTED is the new name of UPLOAD_VERIFICATION_ERROR
  38         const UPLOAD_VERIFICATION_ERROR = 11;
  39         const HOOK_ABORTED = 11;
  40         const FILE_TOO_LARGE = 12;
  41         const WINDOWS_NONASCII_FILENAME = 13;
  42         const FILENAME_TOO_LONG = 14;
  43
  44         public function getVerificationErrorCode( $error ) {
  45                 $code_to_status = array(self::EMPTY_FILE => 'empty-file',
  46                                                                 self::FILE_TOO_LARGE => 'file-too-large',
  47                                                                 self::FILETYPE_MISSING => 'filetype-missing',
  48                                                                 self::FILETYPE_BADTYPE => 'filetype-banned',
  49                                                                 self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  50                                                                 self::ILLEGAL_FILENAME => 'illegal-filename',
  51                                                                 self::OVERWRITE_EXISTING_FILE => 'overwrite',
  52                                                                 self::VERIFICATION_ERROR => 'verification-error',
  53                                                                 self::HOOK_ABORTED =>  'hookaborted',
  54                                                                 self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
  55                                                                 self::FILENAME_TOO_LONG => 'filename-toolong',
  56                 );
  57                 if( isset( $code_to_status[$error] ) ) {
  58                         return $code_to_status[$error];
  59                 }
  60
  61                 return 'unknown-error';
  62         }
  63
  64         /**
  65          * Returns true if uploads are enabled.
  66          * Can be override by subclasses.
  67          * @return bool
  68          */
  69         public static function isEnabled() {
  70                 global $wgEnableUploads;
  71
  72                 if ( !$wgEnableUploads ) {
  73                         return false;
  74                 }
  75
  76                 # Check php's file_uploads setting
  77                 return wfIsHipHop() || wfIniGetBool( 'file_uploads' );
  78         }
  79
  80         /**
  81          * Returns true if the user can use this upload module or else a string
  82          * identifying the missing permission.
  83          * Can be overriden by subclasses.
  84          *
  85          * @param $user User
  86          * @return bool
  87          */
  88         public static function isAllowed( $user ) {
  89                 foreach ( array( 'upload', 'edit' ) as $permission ) {
  90                         if ( !$user->isAllowed( $permission ) ) {
  91                                 return $permission;
  92                         }
  93                 }
  94                 return true;
  95         }
  96
  97         // Upload handlers. Should probably just be a global.
  98         static $uploadHandlers = array( 'Stash', 'File', 'Url' );
  99
 100         /**
 101          * Create a form of UploadBase depending on wpSourceType and initializes it
 102          *
 103          * @param $request WebRequest
 104          * @param $type
 105          * @return null
 106          */
 107         public static function createFromRequest( &$request, $type = null ) {
 108                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 109
 110                 if( !$type ) {
 111                         return null;
 112                 }
 113
 114                 // Get the upload class
 115                 $type = ucfirst( $type );
 116
 117                 // Give hooks the chance to handle this request
 118                 $className = null;
 119                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 120                 if ( is_null( $className ) ) {
 121                         $className = 'UploadFrom' . $type;
 122                         wfDebug( __METHOD__ . ": class name: $className\n" );
 123                         if( !in_array( $type, self::$uploadHandlers ) ) {
 124                                 return null;
 125                         }
 126                 }
 127
 128                 // Check whether this upload class is enabled
 129                 if( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 130                         return null;
 131                 }
 132
 133                 // Check whether the request is valid
 134                 if( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 135                         return null;
 136                 }
 137
 138                 $handler = new $className;
 139
 140                 $handler->initializeFromRequest( $request );
 141                 return $handler;
 142         }
 143
 144         /**
 145          * Check whether a request if valid for this handler
 146          * @return bool
 147          */
 148         public static function isValidRequest( $request ) {
 149                 return false;
 150         }
 151
 152         public function __construct() {}
 153
 154         /**
 155          * Returns the upload type. Should be overridden by child classes
 156          *
 157          * @since 1.18
 158          * @return string
 159          */
 160         public function getSourceType() { return null; }
 161
 162         /**
 163          * Initialize the path information
 164          * @param $name string the desired destination name
 165          * @param $tempPath string the temporary path
 166          * @param $fileSize int the file size
 167          * @param $removeTempFile bool (false) remove the temporary file?
 168          * @return null
 169          */
 170         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 171                 $this->mDesiredDestName = $name;
 172                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 173                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 174                 }
 175                 $this->mTempPath = $tempPath;
 176                 $this->mFileSize = $fileSize;
 177                 $this->mRemoveTempFile = $removeTempFile;
 178         }
 179
 180         /**
 181          * Initialize from a WebRequest. Override this in a subclass.
 182          */
 183         public abstract function initializeFromRequest( &$request );
 184
 185         /**
 186          * Fetch the file. Usually a no-op
 187          * @return Status
 188          */
 189         public function fetchFile() {
 190                 return Status::newGood();
 191         }
 192
 193         /**
 194          * Return true if the file is empty
 195          * @return bool
 196          */
 197         public function isEmptyFile() {
 198                 return empty( $this->mFileSize );
 199         }
 200
 201         /**
 202          * Return the file size
 203          * @return integer
 204          */
 205         public function getFileSize() {
 206                 return $this->mFileSize;
 207         }
 208
 209         /**
 210          * @param $srcPath String: the source path
 211          * @return stringthe real path if it was a virtual URL
 212          */
 213         function getRealPath( $srcPath ) {
 214                 wfProfileIn( __METHOD__ );
 215                 $repo = RepoGroup::singleton()->getLocalRepo();
 216                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 217                         // @TODO: just make uploads work with storage paths
 218                         // UploadFromStash loads files via virtuals URLs
 219                         $tmpFile = $repo->getLocalCopy( $srcPath );
 220                         $tmpFile->bind( $this ); // keep alive with $thumb
 221                         wfProfileOut( __METHOD__ );
 222                         return $tmpFile->getPath();
 223                 }
 224                 wfProfileOut( __METHOD__ );
 225                 return $srcPath;
 226         }
 227
 228         /**
 229          * Verify whether the upload is sane.
 230          * @return mixed self::OK or else an array with error information
 231          */
 232         public function verifyUpload() {
 233                 wfProfileIn( __METHOD__ );
 234
 235                 /**
 236                  * If there was no filename or a zero size given, give up quick.
 237                  */
 238                 if( $this->isEmptyFile() ) {
 239                         wfProfileOut( __METHOD__ );
 240                         return array( 'status' => self::EMPTY_FILE );
 241                 }
 242
 243                 /**
 244                  * Honor $wgMaxUploadSize
 245                  */
 246                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 247                 if( $this->mFileSize > $maxSize ) {
 248                         wfProfileOut( __METHOD__ );
 249                         return array(
 250                                 'status' => self::FILE_TOO_LARGE,
 251                                 'max' => $maxSize,
 252                         );
 253                 }
 254
 255                 /**
 256                  * Look at the contents of the file; if we can recognize the
 257                  * type but it's corrupt or data of the wrong type, we should
 258                  * probably not accept it.
 259                  */
 260                 $verification = $this->verifyFile();
 261                 if( $verification !== true ) {
 262                         wfProfileOut( __METHOD__ );
 263                         return array(
 264                                 'status' => self::VERIFICATION_ERROR,
 265                                 'details' => $verification
 266                         );
 267                 }
 268
 269                 /**
 270                  * Make sure this file can be created
 271                  */
 272                 $result = $this->validateName();
 273                 if( $result !== true ) {
 274                         wfProfileOut( __METHOD__ );
 275                         return $result;
 276                 }
 277
 278                 $error = '';
 279                 if( !wfRunHooks( 'UploadVerification',
 280                         array( $this->mDestName, $this->mTempPath, &$error ) ) )
 281                 {
 282                         wfProfileOut( __METHOD__ );
 283                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 284                 }
 285
 286                 wfProfileOut( __METHOD__ );
 287                 return array( 'status' => self::OK );
 288         }
 289
 290         /**
 291          * Verify that the name is valid and, if necessary, that we can overwrite
 292          *
 293          * @return mixed true if valid, otherwise and array with 'status'
 294          * and other keys
 295          **/
 296         protected function validateName() {
 297                 $nt = $this->getTitle();
 298                 if( is_null( $nt ) ) {
 299                         $result = array( 'status' => $this->mTitleError );
 300                         if( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 301                                 $result['filtered'] = $this->mFilteredName;
 302                         }
 303                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 304                                 $result['finalExt'] = $this->mFinalExtension;
 305                                 if ( count( $this->mBlackListedExtensions ) ) {
 306                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 307                                 }
 308                         }
 309                         return $result;
 310                 }
 311                 $this->mDestName = $this->getLocalFile()->getName();
 312
 313                 return true;
 314         }
 315
 316         /**
 317          * Verify the mime type
 318          *
 319          * @param $mime string representing the mime
 320          * @return mixed true if the file is verified, an array otherwise
 321          */
 322         protected function verifyMimeType( $mime ) {
 323                 global $wgVerifyMimeType;
 324                 wfProfileIn( __METHOD__ );
 325                 if ( $wgVerifyMimeType ) {
 326                         wfDebug ( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n");
 327                         global $wgMimeTypeBlacklist;
 328                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 329                                 wfProfileOut( __METHOD__ );
 330                                 return array( 'filetype-badmime', $mime );
 331                         }
 332
 333                         # XXX: Missing extension will be caught by validateName() via getTitle()
 334                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 335                                 wfProfileOut( __METHOD__ );
 336                                 return array( 'filetype-mime-mismatch', $this->mFinalExtension, $mime );
 337                         }
 338
 339                         # Check IE type
 340                         $fp = fopen( $this->mTempPath, 'rb' );
 341                         $chunk = fread( $fp, 256 );
 342                         fclose( $fp );
 343
 344                         $magic = MimeMagic::singleton();
 345                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 346                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 347                         foreach ( $ieTypes as $ieType ) {
 348                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 349                                         wfProfileOut( __METHOD__ );
 350                                         return array( 'filetype-bad-ie-mime', $ieType );
 351                                 }
 352                         }
 353                 }
 354
 355                 wfProfileOut( __METHOD__ );
 356                 return true;
 357         }
 358
 359         /**
 360          * Verifies that it's ok to include the uploaded file
 361          *
 362          * @return mixed true of the file is verified, array otherwise.
 363          */
 364         protected function verifyFile() {
 365                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 366                 wfProfileIn( __METHOD__ );
 367
 368                 # get the title, even though we are doing nothing with it, because
 369                 # we need to populate mFinalExtension
 370                 $this->getTitle();
 371
 372                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 373
 374                 # check mime type, if desired
 375                 $mime = $this->mFileProps[ 'file-mime' ];
 376                 $status = $this->verifyMimeType( $mime );
 377                 if ( $status !== true ) {
 378                         wfProfileOut( __METHOD__ );
 379                         return $status;
 380                 }
 381
 382                 # check for htmlish code and javascript
 383                 if ( !$wgDisableUploadScriptChecks ) {
 384                         if( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 385                                 wfProfileOut( __METHOD__ );
 386                                 return array( 'uploadscripted' );
 387                         }
 388                         if( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 389                                 if( $this->detectScriptInSvg( $this->mTempPath ) ) {
 390                                         wfProfileOut( __METHOD__ );
 391                                         return array( 'uploadscripted' );
 392                                 }
 393                         }
 394                 }
 395
 396                 # Check for Java applets, which if uploaded can bypass cross-site
 397                 # restrictions.
 398                 if ( !$wgAllowJavaUploads ) {
 399                         $this->mJavaDetected = false;
 400                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 401                                 array( $this, 'zipEntryCallback' ) );
 402                         if ( !$zipStatus->isOK() ) {
 403                                 $errors = $zipStatus->getErrorsArray();
 404                                 $error = reset( $errors );
 405                                 if ( $error[0] !== 'zip-wrong-format' ) {
 406                                         wfProfileOut( __METHOD__ );
 407                                         return $error;
 408                                 }
 409                         }
 410                         if ( $this->mJavaDetected ) {
 411                                 wfProfileOut( __METHOD__ );
 412                                 return array( 'uploadjava' );
 413                         }
 414                 }
 415
 416                 # Scan the uploaded file for viruses
 417                 $virus = $this->detectVirus( $this->mTempPath );
 418                 if ( $virus ) {
 419                         wfProfileOut( __METHOD__ );
 420                         return array( 'uploadvirus', $virus );
 421                 }
 422
 423                 $handler = MediaHandler::getHandler( $mime );
 424                 if ( $handler ) {
 425                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 426                         if ( !$handlerStatus->isOK() ) {
 427                                 $errors = $handlerStatus->getErrorsArray();
 428                                 wfProfileOut( __METHOD__ );
 429                                 return reset( $errors );
 430                         }
 431                 }
 432
 433                 wfRunHooks( 'UploadVerifyFile', array( $this, $mime, &$status ) );
 434                 if ( $status !== true ) {
 435                         wfProfileOut( __METHOD__ );
 436                         return $status;
 437                 }
 438
 439                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 440                 wfProfileOut( __METHOD__ );
 441                 return true;
 442         }
 443
 444         /**
 445          * Callback for ZipDirectoryReader to detect Java class files.
 446          */
 447         function zipEntryCallback( $entry ) {
 448                 $names = array( $entry['name'] );
 449
 450                 // If there is a null character, cut off the name at it, because JDK's
 451                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 452                 // were constructed which had ".class\0" followed by a string chosen to
 453                 // make the hash collide with the truncated name, that file could be
 454                 // returned in response to a request for the .class file.
 455                 $nullPos = strpos( $entry['name'], "\000" );
 456                 if ( $nullPos !== false ) {
 457                         $names[] = substr( $entry['name'], 0, $nullPos );
 458                 }
 459
 460                 // If there is a trailing slash in the file name, we have to strip it,
 461                 // because that's what ZIP_GetEntry() does.
 462                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 463                         $this->mJavaDetected = true;
 464                 }
 465         }
 466
 467         /**
 468          * Alias for verifyTitlePermissions. The function was originally 'verifyPermissions'
 469          * but that suggests it's checking the user, when it's really checking the title + user combination.
 470          * @param $user User object to verify the permissions against
 471          * @return mixed An array as returned by getUserPermissionsErrors or true
 472          *               in case the user has proper permissions.
 473          */
 474         public function verifyPermissions( $user ) {
 475                 return $this->verifyTitlePermissions( $user );
 476         }
 477
 478         /**
 479          * Check whether the user can edit, upload and create the image. This
 480          * checks only against the current title; if it returns errors, it may
 481          * very well be that another title will not give errors. Therefore
 482          * isAllowed() should be called as well for generic is-user-blocked or
 483          * can-user-upload checking.
 484          *
 485          * @param $user User object to verify the permissions against
 486          * @return mixed An array as returned by getUserPermissionsErrors or true
 487          *               in case the user has proper permissions.
 488          */
 489         public function verifyTitlePermissions( $user ) {
 490                 /**
 491                  * If the image is protected, non-sysop users won't be able
 492                  * to modify it by uploading a new revision.
 493                  */
 494                 $nt = $this->getTitle();
 495                 if( is_null( $nt ) ) {
 496                         return true;
 497                 }
 498                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 499                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 500                 if ( !$nt->exists() ) {
 501                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 502                 } else {
 503                         $permErrorsCreate = array();
 504                 }
 505                 if( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 506                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 507                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 508                         return $permErrors;
 509                 }
 510
 511                 $overwriteError = $this->checkOverwrite( $user );
 512                 if ( $overwriteError !== true ) {
 513                         return array( $overwriteError );
 514                 }
 515
 516                 return true;
 517         }
 518
 519         /**
 520          * Check for non fatal problems with the file
 521          *
 522          * @return Array of warnings
 523          */
 524         public function checkWarnings() {
 525                 global $wgLang;
 526                 wfProfileIn( __METHOD__ );
 527
 528                 $warnings = array();
 529
 530                 $localFile = $this->getLocalFile();
 531                 $filename = $localFile->getName();
 532
 533                 /**
 534                  * Check whether the resulting filename is different from the desired one,
 535                  * but ignore things like ucfirst() and spaces/underscore things
 536                  */
 537                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 538                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 539
 540                 if( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 541                         $warnings['badfilename'] = $filename;
 542                 }
 543
 544                 // Check whether the file extension is on the unwanted list
 545                 global $wgCheckFileExtensions, $wgFileExtensions;
 546                 if ( $wgCheckFileExtensions ) {
 547                         if ( !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) ) {
 548                                 $warnings['filetype-unwanted-type'] = array( $this->mFinalExtension,
 549                                         $wgLang->commaList( $wgFileExtensions ), count( $wgFileExtensions ) );
 550                         }
 551                 }
 552
 553                 global $wgUploadSizeWarning;
 554                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 555                         $warnings['large-file'] = $wgUploadSizeWarning;
 556                 }
 557
 558                 if ( $this->mFileSize == 0 ) {
 559                         $warnings['emptyfile'] = true;
 560                 }
 561
 562                 $exists = self::getExistsWarning( $localFile );
 563                 if( $exists !== false ) {
 564                         $warnings['exists'] = $exists;
 565                 }
 566
 567                 // Check dupes against existing files
 568                 $hash = FSFile::getSha1Base36FromPath( $this->mTempPath );
 569                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 570                 $title = $this->getTitle();
 571                 // Remove all matches against self
 572                 foreach ( $dupes as $key => $dupe ) {
 573                         if( $title->equals( $dupe->getTitle() ) ) {
 574                                 unset( $dupes[$key] );
 575                         }
 576                 }
 577                 if( $dupes ) {
 578                         $warnings['duplicate'] = $dupes;
 579                 }
 580
 581                 // Check dupes against archives
 582                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 583                 if ( $archivedImage->getID() > 0 ) {
 584                         $warnings['duplicate-archive'] = $archivedImage->getName();
 585                 }
 586
 587                 wfProfileOut( __METHOD__ );
 588                 return $warnings;
 589         }
 590
 591         /**
 592          * Really perform the upload. Stores the file in the local repo, watches
 593          * if necessary and runs the UploadComplete hook.
 594          *
 595          * @param $user User
 596          *
 597          * @return Status indicating the whether the upload succeeded.
 598          */
 599         public function performUpload( $comment, $pageText, $watch, $user ) {
 600                 wfProfileIn( __METHOD__ );
 601
 602                 $status = $this->getLocalFile()->upload(
 603                         $this->mTempPath,
 604                         $comment,
 605                         $pageText,
 606                         File::DELETE_SOURCE,
 607                         $this->mFileProps,
 608                         false,
 609                         $user
 610                 );
 611
 612                 if( $status->isGood() ) {
 613                         if ( $watch ) {
 614                                 $user->addWatch( $this->getLocalFile()->getTitle() );
 615                         }
 616                         wfRunHooks( 'UploadComplete', array( &$this ) );
 617                 }
 618
 619                 wfProfileOut( __METHOD__ );
 620                 return $status;
 621         }
 622
 623         /**
 624          * Returns the title of the file to be uploaded. Sets mTitleError in case
 625          * the name was illegal.
 626          *
 627          * @return Title The title of the file or null in case the name was illegal
 628          */
 629         public function getTitle() {
 630                 if ( $this->mTitle !== false ) {
 631                         return $this->mTitle;
 632                 }
 633
 634                 /* Assume that if a user specified File:Something.jpg, this is an error
 635                  * and that the namespace prefix needs to be stripped of.
 636                  */
 637                 $title = Title::newFromText( $this->mDesiredDestName );
 638                 if ( $title && $title->getNamespace() == NS_FILE ) {
 639                         $this->mFilteredName = $title->getDBkey();
 640                 } else {
 641                         $this->mFilteredName = $this->mDesiredDestName;
 642                 }
 643
 644                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 645                 # exclamation mark, so restrict file name to 240 bytes.
 646                 if ( strlen( $this->mFilteredName ) > 240 ) {
 647                         $this->mTitleError = self::FILENAME_TOO_LONG;
 648                         return $this->mTitle = null;
 649                 }
 650
 651                 /**
 652                  * Chop off any directories in the given filename. Then
 653                  * filter out illegal characters, and try to make a legible name
 654                  * out of it. We'll strip some silently that Title would die on.
 655                  */
 656                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 657                 /* Normalize to title form before we do any further processing */
 658                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 659                 if( is_null( $nt ) ) {
 660                         $this->mTitleError = self::ILLEGAL_FILENAME;
 661                         return $this->mTitle = null;
 662                 }
 663                 $this->mFilteredName = $nt->getDBkey();
 664
 665
 666
 667                 /**
 668                  * We'll want to blacklist against *any* 'extension', and use
 669                  * only the final one for the whitelist.
 670                  */
 671                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 672
 673                 if( count( $ext ) ) {
 674                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 675                 } else {
 676                         $this->mFinalExtension = '';
 677
 678                         # No extension, try guessing one
 679                         $magic = MimeMagic::singleton();
 680                         $mime = $magic->guessMimeType( $this->mTempPath );
 681                         if ( $mime !== 'unknown/unknown' ) {
 682                                 # Get a space separated list of extensions
 683                                 $extList = $magic->getExtensionsForType( $mime );
 684                                 if ( $extList ) {
 685                                         # Set the extension to the canonical extension
 686                                         $this->mFinalExtension = strtok( $extList, ' ' );
 687
 688                                         # Fix up the other variables
 689                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 690                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 691                                         $ext = array( $this->mFinalExtension );
 692                                 }
 693                         }
 694
 695                 }
 696
 697                 /* Don't allow users to override the blacklist (check file extension) */
 698                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 699                 global $wgFileExtensions, $wgFileBlacklist;
 700
 701                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 702
 703                 if ( $this->mFinalExtension == '' ) {
 704                         $this->mTitleError = self::FILETYPE_MISSING;
 705                         return $this->mTitle = null;
 706                 } elseif ( $blackListedExtensions ||
 707                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 708                                         !$this->checkFileExtensionList( $ext, $wgFileExtensions ) ) ) {
 709                         $this->mBlackListedExtensions = $blackListedExtensions;
 710                         $this->mTitleError = self::FILETYPE_BADTYPE;
 711                         return $this->mTitle = null;
 712                 }
 713
 714                 // Windows may be broken with special characters, see bug XXX
 715                 if ( wfIsWindows() && !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() ) ) {
 716                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
 717                         return $this->mTitle = null;
 718                 }
 719
 720                 # If there was more than one "extension", reassemble the base
 721                 # filename to prevent bogus complaints about length
 722                 if( count( $ext ) > 1 ) {
 723                         for( $i = 0; $i < count( $ext ) - 1; $i++ ) {
 724                                 $partname .= '.' . $ext[$i];
 725                         }
 726                 }
 727
 728                 if( strlen( $partname ) < 1 ) {
 729                         $this->mTitleError =  self::MIN_LENGTH_PARTNAME;
 730                         return $this->mTitle = null;
 731                 }
 732
 733                 return $this->mTitle = $nt;
 734         }
 735
 736         /**
 737          * Return the local file and initializes if necessary.
 738          *
 739          * @return LocalFile
 740          */
 741         public function getLocalFile() {
 742                 if( is_null( $this->mLocalFile ) ) {
 743                         $nt = $this->getTitle();
 744                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 745                 }
 746                 return $this->mLocalFile;
 747         }
 748
 749         /**
 750          * If the user does not supply all necessary information in the first upload form submission (either by accident or
 751          * by design) then we may want to stash the file temporarily, get more information, and publish the file later.
 752          *
 753          * This method will stash a file in a temporary directory for later processing, and save the necessary descriptive info
 754          * into the database.
 755          * This method returns the file object, which also has a 'fileKey' property which can be passed through a form or
 756          * API request to find this stashed file again.
 757          *
 758          * @return UploadStashFile stashed file
 759          */
 760         public function stashFile() {
 761                 // was stashSessionFile
 762                 wfProfileIn( __METHOD__ );
 763
 764                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash();
 765                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
 766                 $this->mLocalFile = $file;
 767
 768                 wfProfileOut( __METHOD__ );
 769                 return $file;
 770         }
 771
 772         /**
 773          * Stash a file in a temporary directory, returning a key which can be used to find the file again. See stashFile().
 774          *
 775          * @return String: file key
 776          */
 777         public function stashFileGetKey() {
 778                 return $this->stashFile()->getFileKey();
 779         }
 780
 781         /**
 782          * alias for stashFileGetKey, for backwards compatibility
 783          *
 784          * @return String: file key
 785          */
 786         public function stashSession() {
 787                 return $this->stashFileGetKey();
 788         }
 789
 790         /**
 791          * If we've modified the upload file we need to manually remove it
 792          * on exit to clean up.
 793          */
 794         public function cleanupTempFile() {
 795                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 796                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 797                         unlink( $this->mTempPath );
 798                 }
 799         }
 800
 801         public function getTempPath() {
 802                 return $this->mTempPath;
 803         }
 804
 805         /**
 806          * Split a file into a base name and all dot-delimited 'extensions'
 807          * on the end. Some web server configurations will fall back to
 808          * earlier pseudo-'extensions' to determine type and execute
 809          * scripts, so the blacklist needs to check them all.
 810          *
 811          * @return array
 812          */
 813         public static function splitExtensions( $filename ) {
 814                 $bits = explode( '.', $filename );
 815                 $basename = array_shift( $bits );
 816                 return array( $basename, $bits );
 817         }
 818
 819         /**
 820          * Perform case-insensitive match against a list of file extensions.
 821          * Returns true if the extension is in the list.
 822          *
 823          * @param $ext String
 824          * @param $list Array
 825          * @return Boolean
 826          */
 827         public static function checkFileExtension( $ext, $list ) {
 828                 return in_array( strtolower( $ext ), $list );
 829         }
 830
 831         /**
 832          * Perform case-insensitive match against a list of file extensions.
 833          * Returns an array of matching extensions.
 834          *
 835          * @param $ext Array
 836          * @param $list Array
 837          * @return Boolean
 838          */
 839         public static function checkFileExtensionList( $ext, $list ) {
 840                 return array_intersect( array_map( 'strtolower', $ext ), $list );
 841         }
 842
 843         /**
 844          * Checks if the mime type of the uploaded file matches the file extension.
 845          *
 846          * @param $mime String: the mime type of the uploaded file
 847          * @param $extension String: the filename extension that the file is to be served with
 848          * @return Boolean
 849          */
 850         public static function verifyExtension( $mime, $extension ) {
 851                 $magic = MimeMagic::singleton();
 852
 853                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' )
 854                         if ( !$magic->isRecognizableExtension( $extension ) ) {
 855                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
 856                                         "unrecognized extension '$extension', can't verify\n" );
 857                                 return true;
 858                         } else {
 859                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; ".
 860                                         "recognized extension '$extension', so probably invalid file\n" );
 861                                 return false;
 862                         }
 863
 864                 $match = $magic->isMatchingExtension( $extension, $mime );
 865
 866                 if ( $match === null ) {
 867                         wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
 868                         return true;
 869                 } elseif( $match === true ) {
 870                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
 871
 872                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 873                         return true;
 874
 875                 } else {
 876                         wfDebug( __METHOD__ . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
 877                         return false;
 878                 }
 879         }
 880
 881         /**
 882          * Heuristic for detecting files that *could* contain JavaScript instructions or
 883          * things that may look like HTML to a browser and are thus
 884          * potentially harmful. The present implementation will produce false
 885          * positives in some situations.
 886          *
 887          * @param $file String: pathname to the temporary upload file
 888          * @param $mime String: the mime type of the file
 889          * @param $extension String: the extension of the file
 890          * @return Boolean: true if the file contains something looking like embedded scripts
 891          */
 892         public static function detectScript( $file, $mime, $extension ) {
 893                 global $wgAllowTitlesInSVG;
 894                 wfProfileIn( __METHOD__ );
 895
 896                 # ugly hack: for text files, always look at the entire file.
 897                 # For binary field, just check the first K.
 898
 899                 if( strpos( $mime,'text/' ) === 0 ) {
 900                         $chunk = file_get_contents( $file );
 901                 } else {
 902                         $fp = fopen( $file, 'rb' );
 903                         $chunk = fread( $fp, 1024 );
 904                         fclose( $fp );
 905                 }
 906
 907                 $chunk = strtolower( $chunk );
 908
 909                 if( !$chunk ) {
 910                         wfProfileOut( __METHOD__ );
 911                         return false;
 912                 }
 913
 914                 # decode from UTF-16 if needed (could be used for obfuscation).
 915                 if( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
 916                         $enc = 'UTF-16BE';
 917                 } elseif( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
 918                         $enc = 'UTF-16LE';
 919                 } else {
 920                         $enc = null;
 921                 }
 922
 923                 if( $enc ) {
 924                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
 925                 }
 926
 927                 $chunk = trim( $chunk );
 928
 929                 # @todo FIXME: Convert from UTF-16 if necessarry!
 930                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
 931
 932                 # check for HTML doctype
 933                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
 934                         wfProfileOut( __METHOD__ );
 935                         return true;
 936                 }
 937
 938                 /**
 939                  * Internet Explorer for Windows performs some really stupid file type
 940                  * autodetection which can cause it to interpret valid image files as HTML
 941                  * and potentially execute JavaScript, creating a cross-site scripting
 942                  * attack vectors.
 943                  *
 944                  * Apple's Safari browser also performs some unsafe file type autodetection
 945                  * which can cause legitimate files to be interpreted as HTML if the
 946                  * web server is not correctly configured to send the right content-type
 947                  * (or if you're really uploading plain text and octet streams!)
 948                  *
 949                  * Returns true if IE is likely to mistake the given file for HTML.
 950                  * Also returns true if Safari would mistake the given file for HTML
 951                  * when served with a generic content-type.
 952                  */
 953                 $tags = array(
 954                         '<a href',
 955                         '<body',
 956                         '<head',
 957                         '<html',   #also in safari
 958                         '<img',
 959                         '<pre',
 960                         '<script', #also in safari
 961                         '<table'
 962                 );
 963
 964                 if( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
 965                         $tags[] = '<title';
 966                 }
 967
 968                 foreach( $tags as $tag ) {
 969                         if( false !== strpos( $chunk, $tag ) ) {
 970                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
 971                                 wfProfileOut( __METHOD__ );
 972                                 return true;
 973                         }
 974                 }
 975
 976                 /*
 977                  * look for JavaScript
 978                  */
 979
 980                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
 981                 $chunk = Sanitizer::decodeCharReferences( $chunk );
 982
 983                 # look for script-types
 984                 if( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
 985                         wfDebug( __METHOD__ . ": found script types\n" );
 986                         wfProfileOut( __METHOD__ );
 987                         return true;
 988                 }
 989
 990                 # look for html-style script-urls
 991                 if( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
 992                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
 993                         wfProfileOut( __METHOD__ );
 994                         return true;
 995                 }
 996
 997                 # look for css-style script-urls
 998                 if( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
 999                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1000                         wfProfileOut( __METHOD__ );
1001                         return true;
1002                 }
1003
1004                 wfDebug( __METHOD__ . ": no scripts found\n" );
1005                 wfProfileOut( __METHOD__ );
1006                 return false;
1007         }
1008
1009         protected function detectScriptInSvg( $filename ) {
1010                 $check = new XmlTypeCheck( $filename, array( $this, 'checkSvgScriptCallback' ) );
1011                 return $check->filterMatch;
1012         }
1013
1014         /**
1015          * @todo Replace this with a whitelist filter!
1016          * @return bool
1017          */
1018         public function checkSvgScriptCallback( $element, $attribs ) {
1019                 $strippedElement = $this->stripXmlNamespace( $element );
1020
1021                 /*
1022                  * check for elements that can contain javascript
1023                  */
1024                 if( $strippedElement == 'script' ) {
1025                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1026                         return true;
1027                 }
1028
1029                 # 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>
1030                 if( $strippedElement == 'handler' ) {
1031                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1032                         return true;
1033                 }
1034
1035                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1036                 if( $strippedElement == 'stylesheet' ) {
1037                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1038                         return true;
1039                 }
1040
1041                 foreach( $attribs as $attrib => $value ) {
1042                         $stripped = $this->stripXmlNamespace( $attrib );
1043                         $value = strtolower($value);
1044
1045                         if( substr( $stripped, 0, 2 ) == 'on' ) {
1046                                 wfDebug( __METHOD__ . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1047                                 return true;
1048                         }
1049
1050                         # href with javascript target
1051                         if( $stripped == 'href' && strpos( strtolower( $value ), 'javascript:' ) !== false ) {
1052                                 wfDebug( __METHOD__ . ": Found script in href attribute '$attrib'='$value' in uploaded file.\n" );
1053                                 return true;
1054                         }
1055
1056                         # href with embeded svg as target
1057                         if( $stripped == 'href' && preg_match( '!data:[^,]*image/svg[^,]*,!sim', $value ) ) {
1058                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1059                                 return true;
1060                         }
1061
1062                         # href with embeded (text/xml) svg as target
1063                         if( $stripped == 'href' && preg_match( '!data:[^,]*text/xml[^,]*,!sim', $value ) ) {
1064                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1065                                 return true;
1066                         }
1067
1068                         # use set/animate to add event-handler attribute to parent
1069                         if( ( $strippedElement == 'set' || $strippedElement == 'animate' ) && $stripped == 'attributename' && substr( $value, 0, 2 ) == 'on' ) {
1070                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1071                                 return true;
1072                         }
1073
1074                         # use set to add href attribute to parent element
1075                         if( $strippedElement == 'set' && $stripped == 'attributename' && strpos( $value, 'href' ) !== false ) {
1076                                 wfDebug( __METHOD__ . ": Found svg setting href attibute '$value' in uploaded file.\n" );
1077                                 return true;
1078                         }
1079
1080                         # use set to add a remote / data / script target to an element
1081                         if( $strippedElement == 'set' && $stripped == 'to' &&  preg_match( '!(http|https|data|script):!sim', $value ) ) {
1082                                 wfDebug( __METHOD__ . ": Found svg setting attibute to '$value' in uploaded file.\n" );
1083                                 return true;
1084                         }
1085
1086
1087                         # use handler attribute with remote / data / script
1088                         if( $stripped == 'handler' &&  preg_match( '!(http|https|data|script):!sim', $value ) ) {
1089                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script '$attrib'='$value' in uploaded file.\n" );
1090                                 return true;
1091                         }
1092
1093                         # use CSS styles to bring in remote code
1094                         # catch url("http:..., url('http:..., url(http:..., but not url("#..., url('#..., url(#....
1095                         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, $matches ) ) {
1096                                 foreach ($matches[1] as $match) {
1097                                         if (!preg_match( '!(?:font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke)\s*:\s*url\s*\(\s*(#|\'#|"#)!sim', $match ) ) {
1098                                                 wfDebug( __METHOD__ . ": Found svg setting a style with remote url '$attrib'='$value' in uploaded file.\n" );
1099                                                 return true;
1100                                         }
1101                                 }
1102                         }
1103
1104                         # image filters can pull in url, which could be svg that executes scripts
1105                         if( $strippedElement == 'image' && $stripped == 'filter' && preg_match( '!url\s*\(!sim', $value ) ) {
1106                                 wfDebug( __METHOD__ . ": Found image filter with url: \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1107                                 return true;
1108                         }
1109
1110                 }
1111
1112                 return false; //No scripts detected
1113         }
1114
1115         private function stripXmlNamespace( $name ) {
1116                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1117                 $parts = explode( ':', strtolower( $name ) );
1118                 return array_pop( $parts );
1119         }
1120
1121         /**
1122          * Generic wrapper function for a virus scanner program.
1123          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1124          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1125          *
1126          * @param $file String: pathname to the temporary upload file
1127          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
1128          *         or a string containing feedback from the virus scanner if a virus was found.
1129          *         If textual feedback is missing but a virus was found, this function returns true.
1130          */
1131         public static function detectVirus( $file ) {
1132                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1133                 wfProfileIn( __METHOD__ );
1134
1135                 if ( !$wgAntivirus ) {
1136                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1137                         wfProfileOut( __METHOD__ );
1138                         return null;
1139                 }
1140
1141                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1142                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1143                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1144                                 array( 'virus-badscanner', $wgAntivirus ) );
1145                         wfProfileOut( __METHOD__ );
1146                         return wfMsg( 'virus-unknownscanner' ) . " $wgAntivirus";
1147                 }
1148
1149                 # look up scanner configuration
1150                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1151                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1152                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
1153                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
1154
1155                 if ( strpos( $command, "%f" ) === false ) {
1156                         # simple pattern: append file to scan
1157                         $command .= " " . wfEscapeShellArg( $file );
1158                 } else {
1159                         # complex pattern: replace "%f" with file to scan
1160                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
1161                 }
1162
1163                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1164
1165                 # execute virus scanner
1166                 $exitCode = false;
1167
1168                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1169                 #      that does not seem to be worth the pain.
1170                 #      Ask me (Duesentrieb) about it if it's ever needed.
1171                 $output = wfShellExec( "$command 2>&1", $exitCode );
1172
1173                 # map exit code to AV_xxx constants.
1174                 $mappedCode = $exitCode;
1175                 if ( $exitCodeMap ) {
1176                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1177                                 $mappedCode = $exitCodeMap[$exitCode];
1178                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1179                                 $mappedCode = $exitCodeMap["*"];
1180                         }
1181                 }
1182
1183                 if ( $mappedCode === AV_SCAN_FAILED ) {
1184                         # scan failed (code was mapped to false by $exitCodeMap)
1185                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1186
1187                         if ( $wgAntivirusRequired ) {
1188                                 wfProfileOut( __METHOD__ );
1189                                 return wfMsg( 'virus-scanfailed', array( $exitCode ) );
1190                         } else {
1191                                 wfProfileOut( __METHOD__ );
1192                                 return null;
1193                         }
1194                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1195                         # scan failed because filetype is unknown (probably imune)
1196                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1197                         wfProfileOut( __METHOD__ );
1198                         return null;
1199                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1200                         # no virus found
1201                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1202                         wfProfileOut( __METHOD__ );
1203                         return false;
1204                 } else {
1205                         $output = trim( $output );
1206
1207                         if ( !$output ) {
1208                                 $output = true; #if there's no output, return true
1209                         } elseif ( $msgPattern ) {
1210                                 $groups = array();
1211                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
1212                                         if ( $groups[1] ) {
1213                                                 $output = $groups[1];
1214                                         }
1215                                 }
1216                         }
1217
1218                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1219                         wfProfileOut( __METHOD__ );
1220                         return $output;
1221                 }
1222         }
1223
1224         /**
1225          * Check if there's an overwrite conflict and, if so, if restrictions
1226          * forbid this user from performing the upload.
1227          *
1228          * @param $user User
1229          *
1230          * @return mixed true on success, array on failure
1231          */
1232         private function checkOverwrite( $user ) {
1233                 // First check whether the local file can be overwritten
1234                 $file = $this->getLocalFile();
1235                 if( $file->exists() ) {
1236                         if( !self::userCanReUpload( $user, $file ) ) {
1237                                 return array( 'fileexists-forbidden', $file->getName() );
1238                         } else {
1239                                 return true;
1240                         }
1241                 }
1242
1243                 /* Check shared conflicts: if the local file does not exist, but
1244                  * wfFindFile finds a file, it exists in a shared repository.
1245                  */
1246                 $file = wfFindFile( $this->getTitle() );
1247                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1248                         return array( 'fileexists-shared-forbidden', $file->getName() );
1249                 }
1250
1251                 return true;
1252         }
1253
1254         /**
1255          * Check if a user is the last uploader
1256          *
1257          * @param $user User object
1258          * @param $img String: image name
1259          * @return Boolean
1260          */
1261         public static function userCanReUpload( User $user, $img ) {
1262                 if( $user->isAllowed( 'reupload' ) ) {
1263                         return true; // non-conditional
1264                 }
1265                 if( !$user->isAllowed( 'reupload-own' ) ) {
1266                         return false;
1267                 }
1268                 if( is_string( $img ) ) {
1269                         $img = wfLocalFile( $img );
1270                 }
1271                 if ( !( $img instanceof LocalFile ) ) {
1272                         return false;
1273                 }
1274
1275                 return $user->getId() == $img->getUser( 'id' );
1276         }
1277
1278         /**
1279          * Helper function that does various existence checks for a file.
1280          * The following checks are performed:
1281          * - The file exists
1282          * - Article with the same name as the file exists
1283          * - File exists with normalized extension
1284          * - The file looks like a thumbnail and the original exists
1285          *
1286          * @param $file File The File object to check
1287          * @return mixed False if the file does not exists, else an array
1288          */
1289         public static function getExistsWarning( $file ) {
1290                 if( $file->exists() ) {
1291                         return array( 'warning' => 'exists', 'file' => $file );
1292                 }
1293
1294                 if( $file->getTitle()->getArticleID() ) {
1295                         return array( 'warning' => 'page-exists', 'file' => $file );
1296                 }
1297
1298                 if ( $file->wasDeleted() && !$file->exists() ) {
1299                         return array( 'warning' => 'was-deleted', 'file' => $file );
1300                 }
1301
1302                 if( strpos( $file->getName(), '.' ) == false ) {
1303                         $partname = $file->getName();
1304                         $extension = '';
1305                 } else {
1306                         $n = strrpos( $file->getName(), '.' );
1307                         $extension = substr( $file->getName(), $n + 1 );
1308                         $partname = substr( $file->getName(), 0, $n );
1309                 }
1310                 $normalizedExtension = File::normalizeExtension( $extension );
1311
1312                 if ( $normalizedExtension != $extension ) {
1313                         // We're not using the normalized form of the extension.
1314                         // Normal form is lowercase, using most common of alternate
1315                         // extensions (eg 'jpg' rather than 'JPEG').
1316                         //
1317                         // Check for another file using the normalized form...
1318                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1319                         $file_lc = wfLocalFile( $nt_lc );
1320
1321                         if( $file_lc->exists() ) {
1322                                 return array(
1323                                         'warning' => 'exists-normalized',
1324                                         'file' => $file,
1325                                         'normalizedFile' => $file_lc
1326                                 );
1327                         }
1328                 }
1329
1330                 if ( self::isThumbName( $file->getName() ) ) {
1331                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1332                         $nt_thb = Title::newFromText( substr( $partname , strpos( $partname , '-' ) +1 ) . '.' . $extension, NS_FILE );
1333                         $file_thb = wfLocalFile( $nt_thb );
1334                         if( $file_thb->exists() ) {
1335                                 return array(
1336                                         'warning' => 'thumb',
1337                                         'file' => $file,
1338                                         'thumbFile' => $file_thb
1339                                 );
1340                         } else {
1341                                 // File does not exist, but we just don't like the name
1342                                 return array(
1343                                         'warning' => 'thumb-name',
1344                                         'file' => $file,
1345                                         'thumbFile' => $file_thb
1346                                 );
1347                         }
1348                 }
1349
1350
1351                 foreach( self::getFilenamePrefixBlacklist() as $prefix ) {
1352                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1353                                 return array(
1354                                         'warning' => 'bad-prefix',
1355                                         'file' => $file,
1356                                         'prefix' => $prefix
1357                                 );
1358                         }
1359                 }
1360
1361                 return false;
1362         }
1363
1364         /**
1365          * Helper function that checks whether the filename looks like a thumbnail
1366          * @return bool
1367          */
1368         public static function isThumbName( $filename ) {
1369                 $n = strrpos( $filename, '.' );
1370                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1371                 return (
1372                                         substr( $partname , 3, 3 ) == 'px-' ||
1373                                         substr( $partname , 2, 3 ) == 'px-'
1374                                 ) &&
1375                                 preg_match( "/[0-9]{2}/" , substr( $partname , 0, 2 ) );
1376         }
1377
1378         /**
1379          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1380          *
1381          * @return array list of prefixes
1382          */
1383         public static function getFilenamePrefixBlacklist() {
1384                 $blacklist = array();
1385                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
1386                 if( !$message->isDisabled() ) {
1387                         $lines = explode( "\n", $message->plain() );
1388                         foreach( $lines as $line ) {
1389                                 // Remove comment lines
1390                                 $comment = substr( trim( $line ), 0, 1 );
1391                                 if ( $comment == '#' || $comment == '' ) {
1392                                         continue;
1393                                 }
1394                                 // Remove additional comments after a prefix
1395                                 $comment = strpos( $line, '#' );
1396                                 if ( $comment > 0 ) {
1397                                         $line = substr( $line, 0, $comment-1 );
1398                                 }
1399                                 $blacklist[] = trim( $line );
1400                         }
1401                 }
1402                 return $blacklist;
1403         }
1404
1405         /**
1406          * Gets image info about the file just uploaded.
1407          *
1408          * Also has the effect of setting metadata to be an 'indexed tag name' in returned API result if
1409          * 'metadata' was requested. Oddly, we have to pass the "result" object down just so it can do that
1410          * with the appropriate format, presumably.
1411          *
1412          * @param $result ApiResult:
1413          * @return Array: image info
1414          */
1415         public function getImageInfo( $result ) {
1416                 $file = $this->getLocalFile();
1417                 // TODO This cries out for refactoring. We really want to say $file->getAllInfo(); here.
1418                 // Perhaps "info" methods should be moved into files, and the API should just wrap them in queries.
1419                 if ( $file instanceof UploadStashFile ) {
1420                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
1421                         $info = ApiQueryStashImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1422                 } else {
1423                         $imParam = ApiQueryImageInfo::getPropertyNames();
1424                         $info = ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1425                 }
1426                 return $info;
1427         }
1428
1429
1430         public function convertVerifyErrorToStatus( $error ) {
1431                 $code = $error['status'];
1432                 unset( $code['status'] );
1433                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
1434         }
1435
1436         public static function getMaxUploadSize( $forType = null ) {
1437                 global $wgMaxUploadSize;
1438
1439                 if ( is_array( $wgMaxUploadSize ) ) {
1440                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
1441                                 return $wgMaxUploadSize[$forType];
1442                         } else {
1443                                 return $wgMaxUploadSize['*'];
1444                         }
1445                 } else {
1446                         return intval( $wgMaxUploadSize );
1447                 }
1448
1449         }
1450 }