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 use MediaWiki\MediaWikiServices;
  24 use MediaWiki\Shell\Shell;
  25
  26 /**
  27  * @defgroup Upload Upload related
  28  */
  29
  30 /**
  31  * @ingroup Upload
  32  *
  33  * UploadBase and subclasses are the backend of MediaWiki's file uploads.
  34  * The frontends are formed by ApiUpload and SpecialUpload.
  35  *
  36  * @author Brion Vibber
  37  * @author Bryan Tong Minh
  38  * @author Michael Dale
  39  */
  40 abstract class UploadBase {
  41         /** @var string Local file system path to the file to upload (or a local copy) */
  42         protected $mTempPath;
  43         /** @var TempFSFile|null Wrapper to handle deleting the temp file */
  44         protected $tempFileObj;
  45
  46         protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
  47         protected $mTitle = false, $mTitleError = 0;
  48         protected $mFilteredName, $mFinalExtension;
  49         protected $mLocalFile, $mStashFile, $mFileSize, $mFileProps;
  50         protected $mBlackListedExtensions;
  51         protected $mJavaDetected, $mSVGNSError;
  52
  53         protected static $safeXmlEncodings = [
  54                 'UTF-8',
  55                 'ISO-8859-1',
  56                 'ISO-8859-2',
  57                 'UTF-16',
  58                 'UTF-32',
  59                 'WINDOWS-1250',
  60                 'WINDOWS-1251',
  61                 'WINDOWS-1252',
  62                 'WINDOWS-1253',
  63                 'WINDOWS-1254',
  64                 'WINDOWS-1255',
  65                 'WINDOWS-1256',
  66                 'WINDOWS-1257',
  67                 'WINDOWS-1258',
  68         ];
  69
  70         const SUCCESS = 0;
  71         const OK = 0;
  72         const EMPTY_FILE = 3;
  73         const MIN_LENGTH_PARTNAME = 4;
  74         const ILLEGAL_FILENAME = 5;
  75         const OVERWRITE_EXISTING_FILE = 7; # Not used anymore; handled by verifyTitlePermissions()
  76         const FILETYPE_MISSING = 8;
  77         const FILETYPE_BADTYPE = 9;
  78         const VERIFICATION_ERROR = 10;
  79         const HOOK_ABORTED = 11;
  80         const FILE_TOO_LARGE = 12;
  81         const WINDOWS_NONASCII_FILENAME = 13;
  82         const FILENAME_TOO_LONG = 14;
  83
  84         /**
  85          * @param int $error
  86          * @return string
  87          */
  88         public function getVerificationErrorCode( $error ) {
  89                 $code_to_status = [
  90                         self::EMPTY_FILE => 'empty-file',
  91                         self::FILE_TOO_LARGE => 'file-too-large',
  92                         self::FILETYPE_MISSING => 'filetype-missing',
  93                         self::FILETYPE_BADTYPE => 'filetype-banned',
  94                         self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  95                         self::ILLEGAL_FILENAME => 'illegal-filename',
  96                         self::OVERWRITE_EXISTING_FILE => 'overwrite',
  97                         self::VERIFICATION_ERROR => 'verification-error',
  98                         self::HOOK_ABORTED => 'hookaborted',
  99                         self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
 100                         self::FILENAME_TOO_LONG => 'filename-toolong',
 101                 ];
 102                 return $code_to_status[$error] ?? 'unknown-error';
 103         }
 104
 105         /**
 106          * Returns true if uploads are enabled.
 107          * Can be override by subclasses.
 108          * @return bool
 109          */
 110         public static function isEnabled() {
 111                 global $wgEnableUploads;
 112
 113                 if ( !$wgEnableUploads ) {
 114                         return false;
 115                 }
 116
 117                 # Check php's file_uploads setting
 118                 return wfIsHHVM() || wfIniGetBool( 'file_uploads' );
 119         }
 120
 121         /**
 122          * Returns true if the user can use this upload module or else a string
 123          * identifying the missing permission.
 124          * Can be overridden by subclasses.
 125          *
 126          * @param User $user
 127          * @return bool|string
 128          */
 129         public static function isAllowed( $user ) {
 130                 foreach ( [ 'upload', 'edit' ] as $permission ) {
 131                         if ( !$user->isAllowed( $permission ) ) {
 132                                 return $permission;
 133                         }
 134                 }
 135
 136                 return true;
 137         }
 138
 139         /**
 140          * Returns true if the user has surpassed the upload rate limit, false otherwise.
 141          *
 142          * @param User $user
 143          * @return bool
 144          */
 145         public static function isThrottled( $user ) {
 146                 return $user->pingLimiter( 'upload' );
 147         }
 148
 149         // Upload handlers. Should probably just be a global.
 150         private static $uploadHandlers = [ 'Stash', 'File', 'Url' ];
 151
 152         /**
 153          * Create a form of UploadBase depending on wpSourceType and initializes it
 154          *
 155          * @param WebRequest &$request
 156          * @param string|null $type
 157          * @return null|UploadBase
 158          */
 159         public static function createFromRequest( &$request, $type = null ) {
 160                 $type = $type ?: $request->getVal( 'wpSourceType', 'File' );
 161
 162                 if ( !$type ) {
 163                         return null;
 164                 }
 165
 166                 // Get the upload class
 167                 $type = ucfirst( $type );
 168
 169                 // Give hooks the chance to handle this request
 170                 $className = null;
 171                 Hooks::run( 'UploadCreateFromRequest', [ $type, &$className ] );
 172                 if ( is_null( $className ) ) {
 173                         $className = 'UploadFrom' . $type;
 174                         wfDebug( __METHOD__ . ": class name: $className\n" );
 175                         if ( !in_array( $type, self::$uploadHandlers ) ) {
 176                                 return null;
 177                         }
 178                 }
 179
 180                 // Check whether this upload class is enabled
 181                 if ( !call_user_func( [ $className, 'isEnabled' ] ) ) {
 182                         return null;
 183                 }
 184
 185                 // Check whether the request is valid
 186                 if ( !call_user_func( [ $className, 'isValidRequest' ], $request ) ) {
 187                         return null;
 188                 }
 189
 190                 /** @var UploadBase $handler */
 191                 $handler = new $className;
 192
 193                 $handler->initializeFromRequest( $request );
 194
 195                 return $handler;
 196         }
 197
 198         /**
 199          * Check whether a request if valid for this handler
 200          * @param WebRequest $request
 201          * @return bool
 202          */
 203         public static function isValidRequest( $request ) {
 204                 return false;
 205         }
 206
 207         public function __construct() {
 208         }
 209
 210         /**
 211          * Returns the upload type. Should be overridden by child classes
 212          *
 213          * @since 1.18
 214          * @return string
 215          */
 216         public function getSourceType() {
 217                 return null;
 218         }
 219
 220         /**
 221          * Initialize the path information
 222          * @param string $name The desired destination name
 223          * @param string $tempPath The temporary path
 224          * @param int $fileSize The file size
 225          * @param bool $removeTempFile (false) remove the temporary file?
 226          * @throws MWException
 227          */
 228         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 229                 $this->mDesiredDestName = $name;
 230                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 231                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 232                 }
 233
 234                 $this->setTempFile( $tempPath, $fileSize );
 235                 $this->mRemoveTempFile = $removeTempFile;
 236         }
 237
 238         /**
 239          * Initialize from a WebRequest. Override this in a subclass.
 240          *
 241          * @param WebRequest &$request
 242          */
 243         abstract public function initializeFromRequest( &$request );
 244
 245         /**
 246          * @param string $tempPath File system path to temporary file containing the upload
 247          * @param int|null $fileSize
 248          */
 249         protected function setTempFile( $tempPath, $fileSize = null ) {
 250                 $this->mTempPath = $tempPath;
 251                 $this->mFileSize = $fileSize ?: null;
 252                 if ( strlen( $this->mTempPath ) && file_exists( $this->mTempPath ) ) {
 253                         $this->tempFileObj = new TempFSFile( $this->mTempPath );
 254                         if ( !$fileSize ) {
 255                                 $this->mFileSize = filesize( $this->mTempPath );
 256                         }
 257                 } else {
 258                         $this->tempFileObj = null;
 259                 }
 260         }
 261
 262         /**
 263          * Fetch the file. Usually a no-op
 264          * @return Status
 265          */
 266         public function fetchFile() {
 267                 return Status::newGood();
 268         }
 269
 270         /**
 271          * Return true if the file is empty
 272          * @return bool
 273          */
 274         public function isEmptyFile() {
 275                 return empty( $this->mFileSize );
 276         }
 277
 278         /**
 279          * Return the file size
 280          * @return int
 281          */
 282         public function getFileSize() {
 283                 return $this->mFileSize;
 284         }
 285
 286         /**
 287          * Get the base 36 SHA1 of the file
 288          * @return string
 289          */
 290         public function getTempFileSha1Base36() {
 291                 return FSFile::getSha1Base36FromPath( $this->mTempPath );
 292         }
 293
 294         /**
 295          * @param string $srcPath The source path
 296          * @return string|bool The real path if it was a virtual URL Returns false on failure
 297          */
 298         public function getRealPath( $srcPath ) {
 299                 $repo = RepoGroup::singleton()->getLocalRepo();
 300                 if ( FileRepo::isVirtualUrl( $srcPath ) ) {
 301                         /** @todo Just make uploads work with storage paths UploadFromStash
 302                          *  loads files via virtual URLs.
 303                          */
 304                         $tmpFile = $repo->getLocalCopy( $srcPath );
 305                         if ( $tmpFile ) {
 306                                 $tmpFile->bind( $this ); // keep alive with $this
 307                         }
 308                         $path = $tmpFile ? $tmpFile->getPath() : false;
 309                 } else {
 310                         $path = $srcPath;
 311                 }
 312
 313                 return $path;
 314         }
 315
 316         /**
 317          * Verify whether the upload is sane.
 318          * @return mixed Const self::OK or else an array with error information
 319          */
 320         public function verifyUpload() {
 321                 /**
 322                  * If there was no filename or a zero size given, give up quick.
 323                  */
 324                 if ( $this->isEmptyFile() ) {
 325                         return [ 'status' => self::EMPTY_FILE ];
 326                 }
 327
 328                 /**
 329                  * Honor $wgMaxUploadSize
 330                  */
 331                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 332                 if ( $this->mFileSize > $maxSize ) {
 333                         return [
 334                                 'status' => self::FILE_TOO_LARGE,
 335                                 'max' => $maxSize,
 336                         ];
 337                 }
 338
 339                 /**
 340                  * Look at the contents of the file; if we can recognize the
 341                  * type but it's corrupt or data of the wrong type, we should
 342                  * probably not accept it.
 343                  */
 344                 $verification = $this->verifyFile();
 345                 if ( $verification !== true ) {
 346                         return [
 347                                 'status' => self::VERIFICATION_ERROR,
 348                                 'details' => $verification
 349                         ];
 350                 }
 351
 352                 /**
 353                  * Make sure this file can be created
 354                  */
 355                 $result = $this->validateName();
 356                 if ( $result !== true ) {
 357                         return $result;
 358                 }
 359
 360                 $error = '';
 361                 if ( !Hooks::run( 'UploadVerification',
 362                         [ $this->mDestName, $this->mTempPath, &$error ], '1.28' )
 363                 ) {
 364                         return [ 'status' => self::HOOK_ABORTED, 'error' => $error ];
 365                 }
 366
 367                 return [ 'status' => self::OK ];
 368         }
 369
 370         /**
 371          * Verify that the name is valid and, if necessary, that we can overwrite
 372          *
 373          * @return mixed True if valid, otherwise and array with 'status'
 374          * and other keys
 375          */
 376         public function validateName() {
 377                 $nt = $this->getTitle();
 378                 if ( is_null( $nt ) ) {
 379                         $result = [ 'status' => $this->mTitleError ];
 380                         if ( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 381                                 $result['filtered'] = $this->mFilteredName;
 382                         }
 383                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 384                                 $result['finalExt'] = $this->mFinalExtension;
 385                                 if ( count( $this->mBlackListedExtensions ) ) {
 386                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 387                                 }
 388                         }
 389
 390                         return $result;
 391                 }
 392                 $this->mDestName = $this->getLocalFile()->getName();
 393
 394                 return true;
 395         }
 396
 397         /**
 398          * Verify the MIME type.
 399          *
 400          * @note Only checks that it is not an evil MIME. The "does it have
 401          *  correct extension given its MIME type?" check is in verifyFile.
 402          *  in `verifyFile()` that MIME type and file extension correlate.
 403          * @param string $mime Representing the MIME
 404          * @return mixed True if the file is verified, an array otherwise
 405          */
 406         protected function verifyMimeType( $mime ) {
 407                 global $wgVerifyMimeType, $wgVerifyMimeTypeIE;
 408                 if ( $wgVerifyMimeType ) {
 409                         wfDebug( "mime: <$mime> extension: <{$this->mFinalExtension}>\n" );
 410                         global $wgMimeTypeBlacklist;
 411                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 412                                 return [ 'filetype-badmime', $mime ];
 413                         }
 414
 415                         if ( $wgVerifyMimeTypeIE ) {
 416                                 # Check what Internet Explorer would detect
 417                                 $fp = fopen( $this->mTempPath, 'rb' );
 418                                 $chunk = fread( $fp, 256 );
 419                                 fclose( $fp );
 420
 421                                 $magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
 422                                 $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 423                                 $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 424                                 foreach ( $ieTypes as $ieType ) {
 425                                         if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 426                                                 return [ 'filetype-bad-ie-mime', $ieType ];
 427                                         }
 428                                 }
 429                         }
 430                 }
 431
 432                 return true;
 433         }
 434
 435         /**
 436          * Verifies that it's ok to include the uploaded file
 437          *
 438          * @return mixed True of the file is verified, array otherwise.
 439          */
 440         protected function verifyFile() {
 441                 global $wgVerifyMimeType, $wgDisableUploadScriptChecks;
 442
 443                 $status = $this->verifyPartialFile();
 444                 if ( $status !== true ) {
 445                         return $status;
 446                 }
 447
 448                 $mwProps = new MWFileProps( MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer() );
 449                 $this->mFileProps = $mwProps->getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 450                 $mime = $this->mFileProps['mime'];
 451
 452                 if ( $wgVerifyMimeType ) {
 453                         # XXX: Missing extension will be caught by validateName() via getTitle()
 454                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 455                                 return [ 'filetype-mime-mismatch', $this->mFinalExtension, $mime ];
 456                         }
 457                 }
 458
 459                 # check for htmlish code and javascript
 460                 if ( !$wgDisableUploadScriptChecks ) {
 461                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 462                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath, false );
 463                                 if ( $svgStatus !== false ) {
 464                                         return $svgStatus;
 465                                 }
 466                         }
 467                 }
 468
 469                 $handler = MediaHandler::getHandler( $mime );
 470                 if ( $handler ) {
 471                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 472                         if ( !$handlerStatus->isOK() ) {
 473                                 $errors = $handlerStatus->getErrorsArray();
 474
 475                                 return reset( $errors );
 476                         }
 477                 }
 478
 479                 $error = true;
 480                 Hooks::run( 'UploadVerifyFile', [ $this, $mime, &$error ] );
 481                 if ( $error !== true ) {
 482                         if ( !is_array( $error ) ) {
 483                                 $error = [ $error ];
 484                         }
 485                         return $error;
 486                 }
 487
 488                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 489
 490                 return true;
 491         }
 492
 493         /**
 494          * A verification routine suitable for partial files
 495          *
 496          * Runs the blacklist checks, but not any checks that may
 497          * assume the entire file is present.
 498          *
 499          * @return mixed True for valid or array with error message key.
 500          */
 501         protected function verifyPartialFile() {
 502                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 503
 504                 # getTitle() sets some internal parameters like $this->mFinalExtension
 505                 $this->getTitle();
 506
 507                 $mwProps = new MWFileProps( MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer() );
 508                 $this->mFileProps = $mwProps->getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 509
 510                 # check MIME type, if desired
 511                 $mime = $this->mFileProps['file-mime'];
 512                 $status = $this->verifyMimeType( $mime );
 513                 if ( $status !== true ) {
 514                         return $status;
 515                 }
 516
 517                 # check for htmlish code and javascript
 518                 if ( !$wgDisableUploadScriptChecks ) {
 519                         if ( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 520                                 return [ 'uploadscripted' ];
 521                         }
 522                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 523                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath, true );
 524                                 if ( $svgStatus !== false ) {
 525                                         return $svgStatus;
 526                                 }
 527                         }
 528                 }
 529
 530                 # Check for Java applets, which if uploaded can bypass cross-site
 531                 # restrictions.
 532                 if ( !$wgAllowJavaUploads ) {
 533                         $this->mJavaDetected = false;
 534                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 535                                 [ $this, 'zipEntryCallback' ] );
 536                         if ( !$zipStatus->isOK() ) {
 537                                 $errors = $zipStatus->getErrorsArray();
 538                                 $error = reset( $errors );
 539                                 if ( $error[0] !== 'zip-wrong-format' ) {
 540                                         return $error;
 541                                 }
 542                         }
 543                         if ( $this->mJavaDetected ) {
 544                                 return [ 'uploadjava' ];
 545                         }
 546                 }
 547
 548                 # Scan the uploaded file for viruses
 549                 $virus = $this->detectVirus( $this->mTempPath );
 550                 if ( $virus ) {
 551                         return [ 'uploadvirus', $virus ];
 552                 }
 553
 554                 return true;
 555         }
 556
 557         /**
 558          * Callback for ZipDirectoryReader to detect Java class files.
 559          *
 560          * @param array $entry
 561          */
 562         public function zipEntryCallback( $entry ) {
 563                 $names = [ $entry['name'] ];
 564
 565                 // If there is a null character, cut off the name at it, because JDK's
 566                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 567                 // were constructed which had ".class\0" followed by a string chosen to
 568                 // make the hash collide with the truncated name, that file could be
 569                 // returned in response to a request for the .class file.
 570                 $nullPos = strpos( $entry['name'], "\000" );
 571                 if ( $nullPos !== false ) {
 572                         $names[] = substr( $entry['name'], 0, $nullPos );
 573                 }
 574
 575                 // If there is a trailing slash in the file name, we have to strip it,
 576                 // because that's what ZIP_GetEntry() does.
 577                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 578                         $this->mJavaDetected = true;
 579                 }
 580         }
 581
 582         /**
 583          * Alias for verifyTitlePermissions. The function was originally
 584          * 'verifyPermissions', but that suggests it's checking the user, when it's
 585          * really checking the title + user combination.
 586          *
 587          * @param User $user User object to verify the permissions against
 588          * @return mixed An array as returned by getUserPermissionsErrors or true
 589          *   in case the user has proper permissions.
 590          */
 591         public function verifyPermissions( $user ) {
 592                 return $this->verifyTitlePermissions( $user );
 593         }
 594
 595         /**
 596          * Check whether the user can edit, upload and create the image. This
 597          * checks only against the current title; if it returns errors, it may
 598          * very well be that another title will not give errors. Therefore
 599          * isAllowed() should be called as well for generic is-user-blocked or
 600          * can-user-upload checking.
 601          *
 602          * @param User $user User object to verify the permissions against
 603          * @return mixed An array as returned by getUserPermissionsErrors or true
 604          *   in case the user has proper permissions.
 605          */
 606         public function verifyTitlePermissions( $user ) {
 607                 /**
 608                  * If the image is protected, non-sysop users won't be able
 609                  * to modify it by uploading a new revision.
 610                  */
 611                 $nt = $this->getTitle();
 612                 if ( is_null( $nt ) ) {
 613                         return true;
 614                 }
 615                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 616                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 617                 if ( !$nt->exists() ) {
 618                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 619                 } else {
 620                         $permErrorsCreate = [];
 621                 }
 622                 if ( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 623                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 624                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 625
 626                         return $permErrors;
 627                 }
 628
 629                 $overwriteError = $this->checkOverwrite( $user );
 630                 if ( $overwriteError !== true ) {
 631                         return [ $overwriteError ];
 632                 }
 633
 634                 return true;
 635         }
 636
 637         /**
 638          * Check for non fatal problems with the file.
 639          *
 640          * This should not assume that mTempPath is set.
 641          *
 642          * @return mixed[] Array of warnings
 643          */
 644         public function checkWarnings() {
 645                 $warnings = [];
 646
 647                 $localFile = $this->getLocalFile();
 648                 $localFile->load( File::READ_LATEST );
 649                 $filename = $localFile->getName();
 650                 $hash = $this->getTempFileSha1Base36();
 651
 652                 $badFileName = $this->checkBadFileName( $filename, $this->mDesiredDestName );
 653                 if ( $badFileName !== null ) {
 654                         $warnings['badfilename'] = $badFileName;
 655                 }
 656
 657                 $unwantedFileExtensionDetails = $this->checkUnwantedFileExtensions( $this->mFinalExtension );
 658                 if ( $unwantedFileExtensionDetails !== null ) {
 659                         $warnings['filetype-unwanted-type'] = $unwantedFileExtensionDetails;
 660                 }
 661
 662                 $fileSizeWarnings = $this->checkFileSize( $this->mFileSize );
 663                 if ( $fileSizeWarnings ) {
 664                         $warnings = array_merge( $warnings, $fileSizeWarnings );
 665                 }
 666
 667                 $localFileExistsWarnings = $this->checkLocalFileExists( $localFile, $hash );
 668                 if ( $localFileExistsWarnings ) {
 669                         $warnings = array_merge( $warnings, $localFileExistsWarnings );
 670                 }
 671
 672                 if ( $this->checkLocalFileWasDeleted( $localFile ) ) {
 673                         $warnings['was-deleted'] = $filename;
 674                 }
 675
 676                 // If a file with the same name exists locally then the local file has already been tested
 677                 // for duplication of content
 678                 $ignoreLocalDupes = isset( $warnings[ 'exists '] );
 679                 $dupes = $this->checkAgainstExistingDupes( $hash, $ignoreLocalDupes );
 680                 if ( $dupes ) {
 681                         $warnings['duplicate'] = $dupes;
 682                 }
 683
 684                 $archivedDupes = $this->checkAgainstArchiveDupes( $hash );
 685                 if ( $archivedDupes !== null ) {
 686                         $warnings['duplicate-archive'] = $archivedDupes;
 687                 }
 688
 689                 return $warnings;
 690         }
 691
 692         /**
 693          * Check whether the resulting filename is different from the desired one,
 694          * but ignore things like ucfirst() and spaces/underscore things
 695          *
 696          * @param string $filename
 697          * @param string $desiredFileName
 698          *
 699          * @return string|null String that was determined to be bad or null if the filename is okay
 700          */
 701         private function checkBadFileName( $filename, $desiredFileName ) {
 702                 $comparableName = str_replace( ' ', '_', $desiredFileName );
 703                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 704
 705                 if ( $desiredFileName != $filename && $comparableName != $filename ) {
 706                         return $filename;
 707                 }
 708
 709                 return null;
 710         }
 711
 712         /**
 713          * @param string $fileExtension The file extension to check
 714          *
 715          * @return array|null array with the following keys:
 716          *                    0 => string The final extension being used
 717          *                    1 => string[] The extensions that are allowed
 718          *                    2 => int The number of extensions that are allowed.
 719          */
 720         private function checkUnwantedFileExtensions( $fileExtension ) {
 721                 global $wgCheckFileExtensions, $wgFileExtensions, $wgLang;
 722
 723                 if ( $wgCheckFileExtensions ) {
 724                         $extensions = array_unique( $wgFileExtensions );
 725                         if ( !$this->checkFileExtension( $fileExtension, $extensions ) ) {
 726                                 return [
 727                                         $fileExtension,
 728                                         $wgLang->commaList( $extensions ),
 729                                         count( $extensions )
 730                                 ];
 731                         }
 732                 }
 733
 734                 return null;
 735         }
 736
 737         /**
 738          * @param int $fileSize
 739          *
 740          * @return array warnings
 741          */
 742         private function checkFileSize( $fileSize ) {
 743                 global $wgUploadSizeWarning;
 744
 745                 $warnings = [];
 746
 747                 if ( $wgUploadSizeWarning && ( $fileSize > $wgUploadSizeWarning ) ) {
 748                         $warnings['large-file'] = [ $wgUploadSizeWarning, $fileSize ];
 749                 }
 750
 751                 if ( $fileSize == 0 ) {
 752                         $warnings['empty-file'] = true;
 753                 }
 754
 755                 return $warnings;
 756         }
 757
 758         /**
 759          * @param LocalFile $localFile
 760          * @param string $hash sha1 hash of the file to check
 761          *
 762          * @return array warnings
 763          */
 764         private function checkLocalFileExists( LocalFile $localFile, $hash ) {
 765                 $warnings = [];
 766
 767                 $exists = self::getExistsWarning( $localFile );
 768                 if ( $exists !== false ) {
 769                         $warnings['exists'] = $exists;
 770
 771                         // check if file is an exact duplicate of current file version
 772                         if ( $hash === $localFile->getSha1() ) {
 773                                 $warnings['no-change'] = $localFile;
 774                         }
 775
 776                         // check if file is an exact duplicate of older versions of this file
 777                         $history = $localFile->getHistory();
 778                         foreach ( $history as $oldFile ) {
 779                                 if ( $hash === $oldFile->getSha1() ) {
 780                                         $warnings['duplicate-version'][] = $oldFile;
 781                                 }
 782                         }
 783                 }
 784
 785                 return $warnings;
 786         }
 787
 788         private function checkLocalFileWasDeleted( LocalFile $localFile ) {
 789                 return $localFile->wasDeleted() && !$localFile->exists();
 790         }
 791
 792         /**
 793          * @param string $hash sha1 hash of the file to check
 794          * @param bool $ignoreLocalDupes True to ignore local duplicates
 795          *
 796          * @return File[] Duplicate files, if found.
 797          */
 798         private function checkAgainstExistingDupes( $hash, $ignoreLocalDupes ) {
 799                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 800                 $title = $this->getTitle();
 801                 foreach ( $dupes as $key => $dupe ) {
 802                         if (
 803                                 ( $dupe instanceof LocalFile ) &&
 804                                 $ignoreLocalDupes &&
 805                                 $title->equals( $dupe->getTitle() )
 806                         ) {
 807                                 unset( $dupes[$key] );
 808                         }
 809                 }
 810
 811                 return $dupes;
 812         }
 813
 814         /**
 815          * @param string $hash sha1 hash of the file to check
 816          *
 817          * @return string|null Name of the dupe or empty string if discovered (depending on visibility)
 818          *                     null if the check discovered no dupes.
 819          */
 820         private function checkAgainstArchiveDupes( $hash ) {
 821                 $archivedFile = new ArchivedFile( null, 0, '', $hash );
 822                 if ( $archivedFile->getID() > 0 ) {
 823                         if ( $archivedFile->userCan( File::DELETED_FILE ) ) {
 824                                 return $archivedFile->getName();
 825                         } else {
 826                                 return '';
 827                         }
 828                 }
 829
 830                 return null;
 831         }
 832
 833         /**
 834          * Really perform the upload. Stores the file in the local repo, watches
 835          * if necessary and runs the UploadComplete hook.
 836          *
 837          * @param string $comment
 838          * @param string $pageText
 839          * @param bool $watch Whether the file page should be added to user's watchlist.
 840          *   (This doesn't check $user's permissions.)
 841          * @param User $user
 842          * @param string[] $tags Change tags to add to the log entry and page revision.
 843          *   (This doesn't check $user's permissions.)
 844          * @return Status Indicating the whether the upload succeeded.
 845          */
 846         public function performUpload( $comment, $pageText, $watch, $user, $tags = [] ) {
 847                 $this->getLocalFile()->load( File::READ_LATEST );
 848                 $props = $this->mFileProps;
 849
 850                 $error = null;
 851                 Hooks::run( 'UploadVerifyUpload', [ $this, $user, $props, $comment, $pageText, &$error ] );
 852                 if ( $error ) {
 853                         if ( !is_array( $error ) ) {
 854                                 $error = [ $error ];
 855                         }
 856                         return Status::newFatal( ...$error );
 857                 }
 858
 859                 $status = $this->getLocalFile()->upload(
 860                         $this->mTempPath,
 861                         $comment,
 862                         $pageText,
 863                         File::DELETE_SOURCE,
 864                         $props,
 865                         false,
 866                         $user,
 867                         $tags
 868                 );
 869
 870                 if ( $status->isGood() ) {
 871                         if ( $watch ) {
 872                                 WatchAction::doWatch(
 873                                         $this->getLocalFile()->getTitle(),
 874                                         $user,
 875                                         User::IGNORE_USER_RIGHTS
 876                                 );
 877                         }
 878                         // Avoid PHP 7.1 warning of passing $this by reference
 879                         $uploadBase = $this;
 880                         Hooks::run( 'UploadComplete', [ &$uploadBase ] );
 881
 882                         $this->postProcessUpload();
 883                 }
 884
 885                 return $status;
 886         }
 887
 888         /**
 889          * Perform extra steps after a successful upload.
 890          *
 891          * @since  1.25
 892          */
 893         public function postProcessUpload() {
 894         }
 895
 896         /**
 897          * Returns the title of the file to be uploaded. Sets mTitleError in case
 898          * the name was illegal.
 899          *
 900          * @return Title|null The title of the file or null in case the name was illegal
 901          */
 902         public function getTitle() {
 903                 if ( $this->mTitle !== false ) {
 904                         return $this->mTitle;
 905                 }
 906                 if ( !is_string( $this->mDesiredDestName ) ) {
 907                         $this->mTitleError = self::ILLEGAL_FILENAME;
 908                         $this->mTitle = null;
 909
 910                         return $this->mTitle;
 911                 }
 912                 /* Assume that if a user specified File:Something.jpg, this is an error
 913                  * and that the namespace prefix needs to be stripped of.
 914                  */
 915                 $title = Title::newFromText( $this->mDesiredDestName );
 916                 if ( $title && $title->getNamespace() == NS_FILE ) {
 917                         $this->mFilteredName = $title->getDBkey();
 918                 } else {
 919                         $this->mFilteredName = $this->mDesiredDestName;
 920                 }
 921
 922                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 923                 # exclamation mark, so restrict file name to 240 bytes.
 924                 if ( strlen( $this->mFilteredName ) > 240 ) {
 925                         $this->mTitleError = self::FILENAME_TOO_LONG;
 926                         $this->mTitle = null;
 927
 928                         return $this->mTitle;
 929                 }
 930
 931                 /**
 932                  * Chop off any directories in the given filename. Then
 933                  * filter out illegal characters, and try to make a legible name
 934                  * out of it. We'll strip some silently that Title would die on.
 935                  */
 936                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 937                 /* Normalize to title form before we do any further processing */
 938                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 939                 if ( is_null( $nt ) ) {
 940                         $this->mTitleError = self::ILLEGAL_FILENAME;
 941                         $this->mTitle = null;
 942
 943                         return $this->mTitle;
 944                 }
 945                 $this->mFilteredName = $nt->getDBkey();
 946
 947                 /**
 948                  * We'll want to blacklist against *any* 'extension', and use
 949                  * only the final one for the whitelist.
 950                  */
 951                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 952
 953                 if ( $ext !== [] ) {
 954                         $this->mFinalExtension = trim( end( $ext ) );
 955                 } else {
 956                         $this->mFinalExtension = '';
 957
 958                         # No extension, try guessing one
 959                         $magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
 960                         $mime = $magic->guessMimeType( $this->mTempPath );
 961                         if ( $mime !== 'unknown/unknown' ) {
 962                                 # Get a space separated list of extensions
 963                                 $extList = $magic->getExtensionsForType( $mime );
 964                                 if ( $extList ) {
 965                                         # Set the extension to the canonical extension
 966                                         $this->mFinalExtension = strtok( $extList, ' ' );
 967
 968                                         # Fix up the other variables
 969                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 970                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 971                                         $ext = [ $this->mFinalExtension ];
 972                                 }
 973                         }
 974                 }
 975
 976                 /* Don't allow users to override the blacklist (check file extension) */
 977                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 978                 global $wgFileExtensions, $wgFileBlacklist;
 979
 980                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 981
 982                 if ( $this->mFinalExtension == '' ) {
 983                         $this->mTitleError = self::FILETYPE_MISSING;
 984                         $this->mTitle = null;
 985
 986                         return $this->mTitle;
 987                 } elseif ( $blackListedExtensions ||
 988                         ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 989                                 !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) )
 990                 ) {
 991                         $this->mBlackListedExtensions = $blackListedExtensions;
 992                         $this->mTitleError = self::FILETYPE_BADTYPE;
 993                         $this->mTitle = null;
 994
 995                         return $this->mTitle;
 996                 }
 997
 998                 // Windows may be broken with special characters, see T3780
 999                 if ( !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() )
1000                         && !RepoGroup::singleton()->getLocalRepo()->backendSupportsUnicodePaths()
1001                 ) {
1002                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
1003                         $this->mTitle = null;
1004
1005                         return $this->mTitle;
1006                 }
1007
1008                 # If there was more than one "extension", reassemble the base
1009                 # filename to prevent bogus complaints about length
1010                 if ( count( $ext ) > 1 ) {
1011                         $iterations = count( $ext ) - 1;
1012                         for ( $i = 0; $i < $iterations; $i++ ) {
1013                                 $partname .= '.' . $ext[$i];
1014                         }
1015                 }
1016
1017                 if ( strlen( $partname ) < 1 ) {
1018                         $this->mTitleError = self::MIN_LENGTH_PARTNAME;
1019                         $this->mTitle = null;
1020
1021                         return $this->mTitle;
1022                 }
1023
1024                 $this->mTitle = $nt;
1025
1026                 return $this->mTitle;
1027         }
1028
1029         /**
1030          * Return the local file and initializes if necessary.
1031          *
1032          * @return LocalFile|null
1033          */
1034         public function getLocalFile() {
1035                 if ( is_null( $this->mLocalFile ) ) {
1036                         $nt = $this->getTitle();
1037                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
1038                 }
1039
1040                 return $this->mLocalFile;
1041         }
1042
1043         /**
1044          * @return UploadStashFile|null
1045          */
1046         public function getStashFile() {
1047                 return $this->mStashFile;
1048         }
1049
1050         /**
1051          * Like stashFile(), but respects extensions' wishes to prevent the stashing. verifyUpload() must
1052          * be called before calling this method (unless $isPartial is true).
1053          *
1054          * Upload stash exceptions are also caught and converted to an error status.
1055          *
1056          * @since 1.28
1057          * @param User $user
1058          * @param bool $isPartial Pass `true` if this is a part of a chunked upload (not a complete file).
1059          * @return Status If successful, value is an UploadStashFile instance
1060          */
1061         public function tryStashFile( User $user, $isPartial = false ) {
1062                 if ( !$isPartial ) {
1063                         $error = $this->runUploadStashFileHook( $user );
1064                         if ( $error ) {
1065                                 return Status::newFatal( ...$error );
1066                         }
1067                 }
1068                 try {
1069                         $file = $this->doStashFile( $user );
1070                         return Status::newGood( $file );
1071                 } catch ( UploadStashException $e ) {
1072                         return Status::newFatal( 'uploadstash-exception', get_class( $e ), $e->getMessage() );
1073                 }
1074         }
1075
1076         /**
1077          * @param User $user
1078          * @return array|null Error message and parameters, null if there's no error
1079          */
1080         protected function runUploadStashFileHook( User $user ) {
1081                 $props = $this->mFileProps;
1082                 $error = null;
1083                 Hooks::run( 'UploadStashFile', [ $this, $user, $props, &$error ] );
1084                 if ( $error && !is_array( $error ) ) {
1085                         $error = [ $error ];
1086                 }
1087                 return $error;
1088         }
1089
1090         /**
1091          * If the user does not supply all necessary information in the first upload
1092          * form submission (either by accident or by design) then we may want to
1093          * stash the file temporarily, get more information, and publish the file
1094          * later.
1095          *
1096          * This method will stash a file in a temporary directory for later
1097          * processing, and save the necessary descriptive info into the database.
1098          * This method returns the file object, which also has a 'fileKey' property
1099          * which can be passed through a form or API request to find this stashed
1100          * file again.
1101          *
1102          * @deprecated since 1.28 Use tryStashFile() instead
1103          * @param User|null $user
1104          * @return UploadStashFile Stashed file
1105          * @throws UploadStashBadPathException
1106          * @throws UploadStashFileException
1107          * @throws UploadStashNotLoggedInException
1108          */
1109         public function stashFile( User $user = null ) {
1110                 return $this->doStashFile( $user );
1111         }
1112
1113         /**
1114          * Implementation for stashFile() and tryStashFile().
1115          *
1116          * @param User|null $user
1117          * @return UploadStashFile Stashed file
1118          */
1119         protected function doStashFile( User $user = null ) {
1120                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $user );
1121                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
1122                 $this->mStashFile = $file;
1123
1124                 return $file;
1125         }
1126
1127         /**
1128          * Stash a file in a temporary directory, returning a key which can be used
1129          * to find the file again. See stashFile().
1130          *
1131          * @deprecated since 1.28
1132          * @return string File key
1133          */
1134         public function stashFileGetKey() {
1135                 wfDeprecated( __METHOD__, '1.28' );
1136                 return $this->doStashFile()->getFileKey();
1137         }
1138
1139         /**
1140          * alias for stashFileGetKey, for backwards compatibility
1141          *
1142          * @deprecated since 1.28
1143          * @return string File key
1144          */
1145         public function stashSession() {
1146                 wfDeprecated( __METHOD__, '1.28' );
1147                 return $this->doStashFile()->getFileKey();
1148         }
1149
1150         /**
1151          * If we've modified the upload file we need to manually remove it
1152          * on exit to clean up.
1153          */
1154         public function cleanupTempFile() {
1155                 if ( $this->mRemoveTempFile && $this->tempFileObj ) {
1156                         // Delete when all relevant TempFSFile handles go out of scope
1157                         wfDebug( __METHOD__ . ": Marked temporary file '{$this->mTempPath}' for removal\n" );
1158                         $this->tempFileObj->autocollect();
1159                 }
1160         }
1161
1162         public function getTempPath() {
1163                 return $this->mTempPath;
1164         }
1165
1166         /**
1167          * Split a file into a base name and all dot-delimited 'extensions'
1168          * on the end. Some web server configurations will fall back to
1169          * earlier pseudo-'extensions' to determine type and execute
1170          * scripts, so the blacklist needs to check them all.
1171          *
1172          * @param string $filename
1173          * @return array [ string, string[] ]
1174          */
1175         public static function splitExtensions( $filename ) {
1176                 $bits = explode( '.', $filename );
1177                 $basename = array_shift( $bits );
1178
1179                 return [ $basename, $bits ];
1180         }
1181
1182         /**
1183          * Perform case-insensitive match against a list of file extensions.
1184          * Returns true if the extension is in the list.
1185          *
1186          * @param string $ext
1187          * @param array $list
1188          * @return bool
1189          */
1190         public static function checkFileExtension( $ext, $list ) {
1191                 return in_array( strtolower( $ext ), $list );
1192         }
1193
1194         /**
1195          * Perform case-insensitive match against a list of file extensions.
1196          * Returns an array of matching extensions.
1197          *
1198          * @param string[] $ext
1199          * @param string[] $list
1200          * @return string[]
1201          */
1202         public static function checkFileExtensionList( $ext, $list ) {
1203                 return array_intersect( array_map( 'strtolower', $ext ), $list );
1204         }
1205
1206         /**
1207          * Checks if the MIME type of the uploaded file matches the file extension.
1208          *
1209          * @param string $mime The MIME type of the uploaded file
1210          * @param string $extension The filename extension that the file is to be served with
1211          * @return bool
1212          */
1213         public static function verifyExtension( $mime, $extension ) {
1214                 $magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
1215
1216                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' ) {
1217                         if ( !$magic->isRecognizableExtension( $extension ) ) {
1218                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
1219                                         "unrecognized extension '$extension', can't verify\n" );
1220
1221                                 return true;
1222                         } else {
1223                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; " .
1224                                         "recognized extension '$extension', so probably invalid file\n" );
1225
1226                                 return false;
1227                         }
1228                 }
1229
1230                 $match = $magic->isMatchingExtension( $extension, $mime );
1231
1232                 if ( $match === null ) {
1233                         if ( $magic->getTypesForExtension( $extension ) !== null ) {
1234                                 wfDebug( __METHOD__ . ": No extension known for $mime, but we know a mime for $extension\n" );
1235
1236                                 return false;
1237                         } else {
1238                                 wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
1239
1240                                 return true;
1241                         }
1242                 } elseif ( $match === true ) {
1243                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
1244
1245                         /** @todo If it's a bitmap, make sure PHP or ImageMagick resp. can handle it! */
1246                         return true;
1247                 } else {
1248                         wfDebug( __METHOD__
1249                                 . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
1250
1251                         return false;
1252                 }
1253         }
1254
1255         /**
1256          * Heuristic for detecting files that *could* contain JavaScript instructions or
1257          * things that may look like HTML to a browser and are thus
1258          * potentially harmful. The present implementation will produce false
1259          * positives in some situations.
1260          *
1261          * @param string $file Pathname to the temporary upload file
1262          * @param string $mime The MIME type of the file
1263          * @param string $extension The extension of the file
1264          * @return bool True if the file contains something looking like embedded scripts
1265          */
1266         public static function detectScript( $file, $mime, $extension ) {
1267                 # ugly hack: for text files, always look at the entire file.
1268                 # For binary field, just check the first K.
1269
1270                 $isText = strpos( $mime, 'text/' ) === 0;
1271                 if ( $isText ) {
1272                         $chunk = file_get_contents( $file );
1273                 } else {
1274                         $fp = fopen( $file, 'rb' );
1275                         $chunk = fread( $fp, 1024 );
1276                         fclose( $fp );
1277                 }
1278
1279                 $chunk = strtolower( $chunk );
1280
1281                 if ( !$chunk ) {
1282                         return false;
1283                 }
1284
1285                 # decode from UTF-16 if needed (could be used for obfuscation).
1286                 if ( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
1287                         $enc = 'UTF-16BE';
1288                 } elseif ( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
1289                         $enc = 'UTF-16LE';
1290                 } else {
1291                         $enc = null;
1292                 }
1293
1294                 if ( $enc ) {
1295                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
1296                 }
1297
1298                 $chunk = trim( $chunk );
1299
1300                 /** @todo FIXME: Convert from UTF-16 if necessary! */
1301                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
1302
1303                 # check for HTML doctype
1304                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
1305                         return true;
1306                 }
1307
1308                 // Some browsers will interpret obscure xml encodings as UTF-8, while
1309                 // PHP/expat will interpret the given encoding in the xml declaration (T49304)
1310                 if ( $extension == 'svg' || strpos( $mime, 'image/svg' ) === 0 ) {
1311                         if ( self::checkXMLEncodingMissmatch( $file ) ) {
1312                                 return true;
1313                         }
1314                 }
1315
1316                 // Quick check for HTML heuristics in old IE and Safari.
1317                 //
1318                 // The exact heuristics IE uses are checked separately via verifyMimeType(), so we
1319                 // don't need them all here as it can cause many false positives.
1320                 //
1321                 // Check for `<script` and such still to forbid script tags and embedded HTML in SVG:
1322                 $tags = [
1323                         '<body',
1324                         '<head',
1325                         '<html', # also in safari
1326                         '<script', # also in safari
1327                 ];
1328
1329                 foreach ( $tags as $tag ) {
1330                         if ( strpos( $chunk, $tag ) !== false ) {
1331                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1332
1333                                 return true;
1334                         }
1335                 }
1336
1337                 /*
1338                  * look for JavaScript
1339                  */
1340
1341                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1342                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1343
1344                 # look for script-types
1345                 if ( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1346                         wfDebug( __METHOD__ . ": found script types\n" );
1347
1348                         return true;
1349                 }
1350
1351                 # look for html-style script-urls
1352                 if ( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1353                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1354
1355                         return true;
1356                 }
1357
1358                 # look for css-style script-urls
1359                 if ( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1360                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1361
1362                         return true;
1363                 }
1364
1365                 wfDebug( __METHOD__ . ": no scripts found\n" );
1366
1367                 return false;
1368         }
1369
1370         /**
1371          * Check a whitelist of xml encodings that are known not to be interpreted differently
1372          * by the server's xml parser (expat) and some common browsers.
1373          *
1374          * @param string $file Pathname to the temporary upload file
1375          * @return bool True if the file contains an encoding that could be misinterpreted
1376          */
1377         public static function checkXMLEncodingMissmatch( $file ) {
1378                 global $wgSVGMetadataCutoff;
1379                 $contents = file_get_contents( $file, false, null, 0, $wgSVGMetadataCutoff );
1380                 $encodingRegex = '!encoding[ \t\n\r]*=[ \t\n\r]*[\'"](.*?)[\'"]!si';
1381
1382                 if ( preg_match( "!<\?xml\b(.*?)\?>!si", $contents, $matches ) ) {
1383                         if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1384                                 && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1385                         ) {
1386                                 wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1387
1388                                 return true;
1389                         }
1390                 } elseif ( preg_match( "!<\?xml\b!si", $contents ) ) {
1391                         // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1392                         // bytes. There shouldn't be a legitimate reason for this to happen.
1393                         wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1394
1395                         return true;
1396                 } elseif ( substr( $contents, 0, 4 ) == "\x4C\x6F\xA7\x94" ) {
1397                         // EBCDIC encoded XML
1398                         wfDebug( __METHOD__ . ": EBCDIC Encoded XML\n" );
1399
1400                         return true;
1401                 }
1402
1403                 // It's possible the file is encoded with multi-byte encoding, so re-encode attempt to
1404                 // detect the encoding in case is specifies an encoding not whitelisted in self::$safeXmlEncodings
1405                 $attemptEncodings = [ 'UTF-16', 'UTF-16BE', 'UTF-32', 'UTF-32BE' ];
1406                 foreach ( $attemptEncodings as $encoding ) {
1407                         Wikimedia\suppressWarnings();
1408                         $str = iconv( $encoding, 'UTF-8', $contents );
1409                         Wikimedia\restoreWarnings();
1410                         if ( $str != '' && preg_match( "!<\?xml\b(.*?)\?>!si", $str, $matches ) ) {
1411                                 if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1412                                         && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1413                                 ) {
1414                                         wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1415
1416                                         return true;
1417                                 }
1418                         } elseif ( $str != '' && preg_match( "!<\?xml\b!si", $str ) ) {
1419                                 // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1420                                 // bytes. There shouldn't be a legitimate reason for this to happen.
1421                                 wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1422
1423                                 return true;
1424                         }
1425                 }
1426
1427                 return false;
1428         }
1429
1430         /**
1431          * @param string $filename
1432          * @param bool $partial
1433          * @return bool|array
1434          */
1435         protected function detectScriptInSvg( $filename, $partial ) {
1436                 $this->mSVGNSError = false;
1437                 $check = new XmlTypeCheck(
1438                         $filename,
1439                         [ $this, 'checkSvgScriptCallback' ],
1440                         true,
1441                         [
1442                                 'processing_instruction_handler' => 'UploadBase::checkSvgPICallback',
1443                                 'external_dtd_handler' => 'UploadBase::checkSvgExternalDTD',
1444                         ]
1445                 );
1446                 if ( $check->wellFormed !== true ) {
1447                         // Invalid xml (T60553)
1448                         // But only when non-partial (T67724)
1449                         return $partial ? false : [ 'uploadinvalidxml' ];
1450                 } elseif ( $check->filterMatch ) {
1451                         if ( $this->mSVGNSError ) {
1452                                 return [ 'uploadscriptednamespace', $this->mSVGNSError ];
1453                         }
1454
1455                         return $check->filterMatchType;
1456                 }
1457
1458                 return false;
1459         }
1460
1461         /**
1462          * Callback to filter SVG Processing Instructions.
1463          * @param string $target Processing instruction name
1464          * @param string $data Processing instruction attribute and value
1465          * @return bool|array
1466          */
1467         public static function checkSvgPICallback( $target, $data ) {
1468                 // Don't allow external stylesheets (T59550)
1469                 if ( preg_match( '/xml-stylesheet/i', $target ) ) {
1470                         return [ 'upload-scripted-pi-callback' ];
1471                 }
1472
1473                 return false;
1474         }
1475
1476         /**
1477          * Verify that DTD urls referenced are only the standard dtds
1478          *
1479          * Browsers seem to ignore external dtds. However just to be on the
1480          * safe side, only allow dtds from the svg standard.
1481          *
1482          * @param string $type PUBLIC or SYSTEM
1483          * @param string $publicId The well-known public identifier for the dtd
1484          * @param string $systemId The url for the external dtd
1485          * @return bool|array
1486          */
1487         public static function checkSvgExternalDTD( $type, $publicId, $systemId ) {
1488                 // This doesn't include the XHTML+MathML+SVG doctype since we don't
1489                 // allow XHTML anyways.
1490                 $allowedDTDs = [
1491                         'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd',
1492                         'http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd',
1493                         'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-basic.dtd',
1494                         'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-tiny.dtd',
1495                         // https://phabricator.wikimedia.org/T168856
1496                         'http://www.w3.org/TR/2001/PR-SVG-20010719/DTD/svg10.dtd',
1497                 ];
1498                 if ( $type !== 'PUBLIC'
1499                         || !in_array( $systemId, $allowedDTDs )
1500                         || strpos( $publicId, "-//W3C//" ) !== 0
1501                 ) {
1502                         return [ 'upload-scripted-dtd' ];
1503                 }
1504                 return false;
1505         }
1506
1507         /**
1508          * @todo Replace this with a whitelist filter!
1509          * @param string $element
1510          * @param array $attribs
1511          * @param array|null $data
1512          * @return bool|array
1513          */
1514         public function checkSvgScriptCallback( $element, $attribs, $data = null ) {
1515                 list( $namespace, $strippedElement ) = $this->splitXmlNamespace( $element );
1516
1517                 // We specifically don't include:
1518                 // http://www.w3.org/1999/xhtml (T62771)
1519                 static $validNamespaces = [
1520                         '',
1521                         'adobe:ns:meta/',
1522                         'http://creativecommons.org/ns#',
1523                         'http://inkscape.sourceforge.net/dtd/sodipodi-0.dtd',
1524                         'http://ns.adobe.com/adobeillustrator/10.0/',
1525                         'http://ns.adobe.com/adobesvgviewerextensions/3.0/',
1526                         'http://ns.adobe.com/extensibility/1.0/',
1527                         'http://ns.adobe.com/flows/1.0/',
1528                         'http://ns.adobe.com/illustrator/1.0/',
1529                         'http://ns.adobe.com/imagereplacement/1.0/',
1530                         'http://ns.adobe.com/pdf/1.3/',
1531                         'http://ns.adobe.com/photoshop/1.0/',
1532                         'http://ns.adobe.com/saveforweb/1.0/',
1533                         'http://ns.adobe.com/variables/1.0/',
1534                         'http://ns.adobe.com/xap/1.0/',
1535                         'http://ns.adobe.com/xap/1.0/g/',
1536                         'http://ns.adobe.com/xap/1.0/g/img/',
1537                         'http://ns.adobe.com/xap/1.0/mm/',
1538                         'http://ns.adobe.com/xap/1.0/rights/',
1539                         'http://ns.adobe.com/xap/1.0/stype/dimensions#',
1540                         'http://ns.adobe.com/xap/1.0/stype/font#',
1541                         'http://ns.adobe.com/xap/1.0/stype/manifestitem#',
1542                         'http://ns.adobe.com/xap/1.0/stype/resourceevent#',
1543                         'http://ns.adobe.com/xap/1.0/stype/resourceref#',
1544                         'http://ns.adobe.com/xap/1.0/t/pg/',
1545                         'http://purl.org/dc/elements/1.1/',
1546                         'http://purl.org/dc/elements/1.1',
1547                         'http://schemas.microsoft.com/visio/2003/svgextensions/',
1548                         'http://sodipodi.sourceforge.net/dtd/sodipodi-0.dtd',
1549                         'http://taptrix.com/inkpad/svg_extensions',
1550                         'http://web.resource.org/cc/',
1551                         'http://www.freesoftware.fsf.org/bkchem/cdml',
1552                         'http://www.inkscape.org/namespaces/inkscape',
1553                         'http://www.opengis.net/gml',
1554                         'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
1555                         'http://www.w3.org/2000/svg',
1556                         'http://www.w3.org/tr/rec-rdf-syntax/',
1557                         'http://www.w3.org/2000/01/rdf-schema#',
1558                 ];
1559
1560                 // Inkscape mangles namespace definitions created by Adobe Illustrator.
1561                 // This is nasty but harmless. (T144827)
1562                 $isBuggyInkscape = preg_match( '/^&(#38;)*ns_[a-z_]+;$/', $namespace );
1563
1564                 if ( !( $isBuggyInkscape || in_array( $namespace, $validNamespaces ) ) ) {
1565                         wfDebug( __METHOD__ . ": Non-svg namespace '$namespace' in uploaded file.\n" );
1566                         /** @todo Return a status object to a closure in XmlTypeCheck, for MW1.21+ */
1567                         $this->mSVGNSError = $namespace;
1568
1569                         return true;
1570                 }
1571
1572                 /*
1573                  * check for elements that can contain javascript
1574                  */
1575                 if ( $strippedElement == 'script' ) {
1576                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1577
1578                         return [ 'uploaded-script-svg', $strippedElement ];
1579                 }
1580
1581                 # e.g., <svg xmlns="http://www.w3.org/2000/svg">
1582                 #  <handler xmlns:ev="http://www.w3.org/2001/xml-events" ev:event="load">alert(1)</handler> </svg>
1583                 if ( $strippedElement == 'handler' ) {
1584                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1585
1586                         return [ 'uploaded-script-svg', $strippedElement ];
1587                 }
1588
1589                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1590                 if ( $strippedElement == 'stylesheet' ) {
1591                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1592
1593                         return [ 'uploaded-script-svg', $strippedElement ];
1594                 }
1595
1596                 # Block iframes, in case they pass the namespace check
1597                 if ( $strippedElement == 'iframe' ) {
1598                         wfDebug( __METHOD__ . ": iframe in uploaded file.\n" );
1599
1600                         return [ 'uploaded-script-svg', $strippedElement ];
1601                 }
1602
1603                 # Check <style> css
1604                 if ( $strippedElement == 'style'
1605                         && self::checkCssFragment( Sanitizer::normalizeCss( $data ) )
1606                 ) {
1607                         wfDebug( __METHOD__ . ": hostile css in style element.\n" );
1608                         return [ 'uploaded-hostile-svg' ];
1609                 }
1610
1611                 foreach ( $attribs as $attrib => $value ) {
1612                         $stripped = $this->stripXmlNamespace( $attrib );
1613                         $value = strtolower( $value );
1614
1615                         if ( substr( $stripped, 0, 2 ) == 'on' ) {
1616                                 wfDebug( __METHOD__
1617                                         . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1618
1619                                 return [ 'uploaded-event-handler-on-svg', $attrib, $value ];
1620                         }
1621
1622                         # Do not allow relative links, or unsafe url schemas.
1623                         # For <a> tags, only data:, http: and https: and same-document
1624                         # fragment links are allowed. For all other tags, only data:
1625                         # and fragment are allowed.
1626                         if ( $stripped == 'href'
1627                                 && $value !== ''
1628                                 && strpos( $value, 'data:' ) !== 0
1629                                 && strpos( $value, '#' ) !== 0
1630                         ) {
1631                                 if ( !( $strippedElement === 'a'
1632                                         && preg_match( '!^https?://!i', $value ) )
1633                                 ) {
1634                                         wfDebug( __METHOD__ . ": Found href attribute <$strippedElement "
1635                                                 . "'$attrib'='$value' in uploaded file.\n" );
1636
1637                                         return [ 'uploaded-href-attribute-svg', $strippedElement, $attrib, $value ];
1638                                 }
1639                         }
1640
1641                         # only allow data: targets that should be safe. This prevents vectors like,
1642                         # image/svg, text/xml, application/xml, and text/html, which can contain scripts
1643                         if ( $stripped == 'href' && strncasecmp( 'data:', $value, 5 ) === 0 ) {
1644                                 // rfc2397 parameters. This is only slightly slower than (;[\w;]+)*.
1645                                 // phpcs:ignore Generic.Files.LineLength
1646                                 $parameters = '(?>;[a-zA-Z0-9\!#$&\'*+.^_`{|}~-]+=(?>[a-zA-Z0-9\!#$&\'*+.^_`{|}~-]+|"(?>[\0-\x0c\x0e-\x21\x23-\x5b\x5d-\x7f]+|\\\\[\0-\x7f])*"))*(?:;base64)?';
1647
1648                                 if ( !preg_match( "!^data:\s*image/(gif|jpeg|jpg|png)$parameters,!i", $value ) ) {
1649                                         wfDebug( __METHOD__ . ": Found href to unwhitelisted data: uri "
1650                                                 . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1651                                         return [ 'uploaded-href-unsafe-target-svg', $strippedElement, $attrib, $value ];
1652                                 }
1653                         }
1654
1655                         # Change href with animate from (http://html5sec.org/#137).
1656                         if ( $stripped === 'attributename'
1657                                 && $strippedElement === 'animate'
1658                                 && $this->stripXmlNamespace( $value ) == 'href'
1659                         ) {
1660                                 wfDebug( __METHOD__ . ": Found animate that might be changing href using from "
1661                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1662
1663                                 return [ 'uploaded-animate-svg', $strippedElement, $attrib, $value ];
1664                         }
1665
1666                         # use set/animate to add event-handler attribute to parent
1667                         if ( ( $strippedElement == 'set' || $strippedElement == 'animate' )
1668                                 && $stripped == 'attributename'
1669                                 && substr( $value, 0, 2 ) == 'on'
1670                         ) {
1671                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with "
1672                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1673
1674                                 return [ 'uploaded-setting-event-handler-svg', $strippedElement, $stripped, $value ];
1675                         }
1676
1677                         # use set to add href attribute to parent element
1678                         if ( $strippedElement == 'set'
1679                                 && $stripped == 'attributename'
1680                                 && strpos( $value, 'href' ) !== false
1681                         ) {
1682                                 wfDebug( __METHOD__ . ": Found svg setting href attribute '$value' in uploaded file.\n" );
1683
1684                                 return [ 'uploaded-setting-href-svg' ];
1685                         }
1686
1687                         # use set to add a remote / data / script target to an element
1688                         if ( $strippedElement == 'set'
1689                                 && $stripped == 'to'
1690                                 && preg_match( '!(http|https|data|script):!sim', $value )
1691                         ) {
1692                                 wfDebug( __METHOD__ . ": Found svg setting attribute to '$value' in uploaded file.\n" );
1693
1694                                 return [ 'uploaded-wrong-setting-svg', $value ];
1695                         }
1696
1697                         # use handler attribute with remote / data / script
1698                         if ( $stripped == 'handler' && preg_match( '!(http|https|data|script):!sim', $value ) ) {
1699                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script "
1700                                         . "'$attrib'='$value' in uploaded file.\n" );
1701
1702                                 return [ 'uploaded-setting-handler-svg', $attrib, $value ];
1703                         }
1704
1705                         # use CSS styles to bring in remote code
1706                         if ( $stripped == 'style'
1707                                 && self::checkCssFragment( Sanitizer::normalizeCss( $value ) )
1708                         ) {
1709                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1710                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1711                                 return [ 'uploaded-remote-url-svg', $attrib, $value ];
1712                         }
1713
1714                         # Several attributes can include css, css character escaping isn't allowed
1715                         $cssAttrs = [ 'font', 'clip-path', 'fill', 'filter', 'marker',
1716                                 'marker-end', 'marker-mid', 'marker-start', 'mask', 'stroke' ];
1717                         if ( in_array( $stripped, $cssAttrs )
1718                                 && self::checkCssFragment( $value )
1719                         ) {
1720                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1721                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1722                                 return [ 'uploaded-remote-url-svg', $attrib, $value ];
1723                         }
1724
1725                         # image filters can pull in url, which could be svg that executes scripts
1726                         # Only allow url( "#foo" ). Do not allow url( http://example.com )
1727                         if ( $strippedElement == 'image'
1728                                 && $stripped == 'filter'
1729                                 && preg_match( '!url\s*\(\s*["\']?[^#]!sim', $value )
1730                         ) {
1731                                 wfDebug( __METHOD__ . ": Found image filter with url: "
1732                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1733
1734                                 return [ 'uploaded-image-filter-svg', $strippedElement, $stripped, $value ];
1735                         }
1736                 }
1737
1738                 return false; // No scripts detected
1739         }
1740
1741         /**
1742          * Check a block of CSS or CSS fragment for anything that looks like
1743          * it is bringing in remote code.
1744          * @param string $value a string of CSS
1745          * @param bool $propOnly only check css properties (start regex with :)
1746          * @return bool true if the CSS contains an illegal string, false if otherwise
1747          */
1748         private static function checkCssFragment( $value ) {
1749                 # Forbid external stylesheets, for both reliability and to protect viewer's privacy
1750                 if ( stripos( $value, '@import' ) !== false ) {
1751                         return true;
1752                 }
1753
1754                 # We allow @font-face to embed fonts with data: urls, so we snip the string
1755                 # 'url' out so this case won't match when we check for urls below
1756                 $pattern = '!(@font-face\s*{[^}]*src:)url(\("data:;base64,)!im';
1757                 $value = preg_replace( $pattern, '$1$2', $value );
1758
1759                 # Check for remote and executable CSS. Unlike in Sanitizer::checkCss, the CSS
1760                 # properties filter and accelerator don't seem to be useful for xss in SVG files.
1761                 # Expression and -o-link don't seem to work either, but filtering them here in case.
1762                 # Additionally, we catch remote urls like url("http:..., url('http:..., url(http:...,
1763                 # but not local ones such as url("#..., url('#..., url(#....
1764                 if ( preg_match( '!expression
1765                                 | -o-link\s*:
1766                                 | -o-link-source\s*:
1767                                 | -o-replace\s*:!imx', $value ) ) {
1768                         return true;
1769                 }
1770
1771                 if ( preg_match_all(
1772                                 "!(\s*(url|image|image-set)\s*\(\s*[\"']?\s*[^#]+.*?\))!sim",
1773                                 $value,
1774                                 $matches
1775                         ) !== 0
1776                 ) {
1777                         # TODO: redo this in one regex. Until then, url("#whatever") matches the first
1778                         foreach ( $matches[1] as $match ) {
1779                                 if ( !preg_match( "!\s*(url|image|image-set)\s*\(\s*(#|'#|\"#)!im", $match ) ) {
1780                                         return true;
1781                                 }
1782                         }
1783                 }
1784
1785                 if ( preg_match( '/[\000-\010\013\016-\037\177]/', $value ) ) {
1786                         return true;
1787                 }
1788
1789                 return false;
1790         }
1791
1792         /**
1793          * Divide the element name passed by the xml parser to the callback into URI and prifix.
1794          * @param string $element
1795          * @return array Containing the namespace URI and prefix
1796          */
1797         private static function splitXmlNamespace( $element ) {
1798                 // 'http://www.w3.org/2000/svg:script' -> [ 'http://www.w3.org/2000/svg', 'script' ]
1799                 $parts = explode( ':', strtolower( $element ) );
1800                 $name = array_pop( $parts );
1801                 $ns = implode( ':', $parts );
1802
1803                 return [ $ns, $name ];
1804         }
1805
1806         /**
1807          * @param string $name
1808          * @return string
1809          */
1810         private function stripXmlNamespace( $name ) {
1811                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1812                 $parts = explode( ':', strtolower( $name ) );
1813
1814                 return array_pop( $parts );
1815         }
1816
1817         /**
1818          * Generic wrapper function for a virus scanner program.
1819          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1820          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1821          *
1822          * @param string $file Pathname to the temporary upload file
1823          * @return bool|null|string False if not virus is found, null if the scan fails or is disabled,
1824          *   or a string containing feedback from the virus scanner if a virus was found.
1825          *   If textual feedback is missing but a virus was found, this function returns true.
1826          */
1827         public static function detectVirus( $file ) {
1828                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1829
1830                 if ( !$wgAntivirus ) {
1831                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1832
1833                         return null;
1834                 }
1835
1836                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1837                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1838                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1839                                 [ 'virus-badscanner', $wgAntivirus ] );
1840
1841                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1842                 }
1843
1844                 # look up scanner configuration
1845                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1846                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1847                 $msgPattern = $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ?? null;
1848
1849                 if ( strpos( $command, "%f" ) === false ) {
1850                         # simple pattern: append file to scan
1851                         $command .= " " . Shell::escape( $file );
1852                 } else {
1853                         # complex pattern: replace "%f" with file to scan
1854                         $command = str_replace( "%f", Shell::escape( $file ), $command );
1855                 }
1856
1857                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1858
1859                 # execute virus scanner
1860                 $exitCode = false;
1861
1862                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1863                 #      that does not seem to be worth the pain.
1864                 #      Ask me (Duesentrieb) about it if it's ever needed.
1865                 $output = wfShellExecWithStderr( $command, $exitCode );
1866
1867                 # map exit code to AV_xxx constants.
1868                 $mappedCode = $exitCode;
1869                 if ( $exitCodeMap ) {
1870                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1871                                 $mappedCode = $exitCodeMap[$exitCode];
1872                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1873                                 $mappedCode = $exitCodeMap["*"];
1874                         }
1875                 }
1876
1877                 /* NB: AV_NO_VIRUS is 0 but AV_SCAN_FAILED is false,
1878                  * so we need the strict equalities === and thus can't use a switch here
1879                  */
1880                 if ( $mappedCode === AV_SCAN_FAILED ) {
1881                         # scan failed (code was mapped to false by $exitCodeMap)
1882                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1883
1884                         $output = $wgAntivirusRequired
1885                                 ? wfMessage( 'virus-scanfailed', [ $exitCode ] )->text()
1886                                 : null;
1887                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1888                         # scan failed because filetype is unknown (probably imune)
1889                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1890                         $output = null;
1891                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1892                         # no virus found
1893                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1894                         $output = false;
1895                 } else {
1896                         $output = trim( $output );
1897
1898                         if ( !$output ) {
1899                                 $output = true; # if there's no output, return true
1900                         } elseif ( $msgPattern ) {
1901                                 $groups = [];
1902                                 if ( preg_match( $msgPattern, $output, $groups ) && $groups[1] ) {
1903                                         $output = $groups[1];
1904                                 }
1905                         }
1906
1907                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1908                 }
1909
1910                 return $output;
1911         }
1912
1913         /**
1914          * Check if there's an overwrite conflict and, if so, if restrictions
1915          * forbid this user from performing the upload.
1916          *
1917          * @param User $user
1918          *
1919          * @return bool|array
1920          */
1921         private function checkOverwrite( $user ) {
1922                 // First check whether the local file can be overwritten
1923                 $file = $this->getLocalFile();
1924                 $file->load( File::READ_LATEST );
1925                 if ( $file->exists() ) {
1926                         if ( !self::userCanReUpload( $user, $file ) ) {
1927                                 return [ 'fileexists-forbidden', $file->getName() ];
1928                         } else {
1929                                 return true;
1930                         }
1931                 }
1932
1933                 /* Check shared conflicts: if the local file does not exist, but
1934                  * wfFindFile finds a file, it exists in a shared repository.
1935                  */
1936                 $file = wfFindFile( $this->getTitle(), [ 'latest' => true ] );
1937                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1938                         return [ 'fileexists-shared-forbidden', $file->getName() ];
1939                 }
1940
1941                 return true;
1942         }
1943
1944         /**
1945          * Check if a user is the last uploader
1946          *
1947          * @param User $user
1948          * @param File $img
1949          * @return bool
1950          */
1951         public static function userCanReUpload( User $user, File $img ) {
1952                 if ( $user->isAllowed( 'reupload' ) ) {
1953                         return true; // non-conditional
1954                 } elseif ( !$user->isAllowed( 'reupload-own' ) ) {
1955                         return false;
1956                 }
1957
1958                 if ( !( $img instanceof LocalFile ) ) {
1959                         return false;
1960                 }
1961
1962                 $img->load();
1963
1964                 return $user->getId() == $img->getUser( 'id' );
1965         }
1966
1967         /**
1968          * Helper function that does various existence checks for a file.
1969          * The following checks are performed:
1970          * - The file exists
1971          * - Article with the same name as the file exists
1972          * - File exists with normalized extension
1973          * - The file looks like a thumbnail and the original exists
1974          *
1975          * @param File $file The File object to check
1976          * @return mixed False if the file does not exists, else an array
1977          */
1978         public static function getExistsWarning( $file ) {
1979                 if ( $file->exists() ) {
1980                         return [ 'warning' => 'exists', 'file' => $file ];
1981                 }
1982
1983                 if ( $file->getTitle()->getArticleID() ) {
1984                         return [ 'warning' => 'page-exists', 'file' => $file ];
1985                 }
1986
1987                 if ( strpos( $file->getName(), '.' ) == false ) {
1988                         $partname = $file->getName();
1989                         $extension = '';
1990                 } else {
1991                         $n = strrpos( $file->getName(), '.' );
1992                         $extension = substr( $file->getName(), $n + 1 );
1993                         $partname = substr( $file->getName(), 0, $n );
1994                 }
1995                 $normalizedExtension = File::normalizeExtension( $extension );
1996
1997                 if ( $normalizedExtension != $extension ) {
1998                         // We're not using the normalized form of the extension.
1999                         // Normal form is lowercase, using most common of alternate
2000                         // extensions (eg 'jpg' rather than 'JPEG').
2001
2002                         // Check for another file using the normalized form...
2003                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
2004                         $file_lc = wfLocalFile( $nt_lc );
2005
2006                         if ( $file_lc->exists() ) {
2007                                 return [
2008                                         'warning' => 'exists-normalized',
2009                                         'file' => $file,
2010                                         'normalizedFile' => $file_lc
2011                                 ];
2012                         }
2013                 }
2014
2015                 // Check for files with the same name but a different extension
2016                 $similarFiles = RepoGroup::singleton()->getLocalRepo()->findFilesByPrefix(
2017                         "{$partname}.", 1 );
2018                 if ( count( $similarFiles ) ) {
2019                         return [
2020                                 'warning' => 'exists-normalized',
2021                                 'file' => $file,
2022                                 'normalizedFile' => $similarFiles[0],
2023                         ];
2024                 }
2025
2026                 if ( self::isThumbName( $file->getName() ) ) {
2027                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
2028                         $nt_thb = Title::newFromText(
2029                                 substr( $partname, strpos( $partname, '-' ) + 1 ) . '.' . $extension,
2030                                 NS_FILE
2031                         );
2032                         $file_thb = wfLocalFile( $nt_thb );
2033                         if ( $file_thb->exists() ) {
2034                                 return [
2035                                         'warning' => 'thumb',
2036                                         'file' => $file,
2037                                         'thumbFile' => $file_thb
2038                                 ];
2039                         } else {
2040                                 // File does not exist, but we just don't like the name
2041                                 return [
2042                                         'warning' => 'thumb-name',
2043                                         'file' => $file,
2044                                         'thumbFile' => $file_thb
2045                                 ];
2046                         }
2047                 }
2048
2049                 foreach ( self::getFilenamePrefixBlacklist() as $prefix ) {
2050                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
2051                                 return [
2052                                         'warning' => 'bad-prefix',
2053                                         'file' => $file,
2054                                         'prefix' => $prefix
2055                                 ];
2056                         }
2057                 }
2058
2059                 return false;
2060         }
2061
2062         /**
2063          * Helper function that checks whether the filename looks like a thumbnail
2064          * @param string $filename
2065          * @return bool
2066          */
2067         public static function isThumbName( $filename ) {
2068                 $n = strrpos( $filename, '.' );
2069                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
2070
2071                 return (
2072                                 substr( $partname, 3, 3 ) == 'px-' ||
2073                                 substr( $partname, 2, 3 ) == 'px-'
2074                         ) &&
2075                         preg_match( "/[0-9]{2}/", substr( $partname, 0, 2 ) );
2076         }
2077
2078         /**
2079          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
2080          *
2081          * @return array List of prefixes
2082          */
2083         public static function getFilenamePrefixBlacklist() {
2084                 $blacklist = [];
2085                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
2086                 if ( !$message->isDisabled() ) {
2087                         $lines = explode( "\n", $message->plain() );
2088                         foreach ( $lines as $line ) {
2089                                 // Remove comment lines
2090                                 $comment = substr( trim( $line ), 0, 1 );
2091                                 if ( $comment == '#' || $comment == '' ) {
2092                                         continue;
2093                                 }
2094                                 // Remove additional comments after a prefix
2095                                 $comment = strpos( $line, '#' );
2096                                 if ( $comment > 0 ) {
2097                                         $line = substr( $line, 0, $comment - 1 );
2098                                 }
2099                                 $blacklist[] = trim( $line );
2100                         }
2101                 }
2102
2103                 return $blacklist;
2104         }
2105
2106         /**
2107          * Gets image info about the file just uploaded.
2108          *
2109          * Also has the effect of setting metadata to be an 'indexed tag name' in
2110          * returned API result if 'metadata' was requested. Oddly, we have to pass
2111          * the "result" object down just so it can do that with the appropriate
2112          * format, presumably.
2113          *
2114          * @param ApiResult $result
2115          * @return array Image info
2116          */
2117         public function getImageInfo( $result ) {
2118                 $localFile = $this->getLocalFile();
2119                 $stashFile = $this->getStashFile();
2120                 // Calling a different API module depending on whether the file was stashed is less than optimal.
2121                 // In fact, calling API modules here at all is less than optimal. Maybe it should be refactored.
2122                 if ( $stashFile ) {
2123                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
2124                         $info = ApiQueryStashImageInfo::getInfo( $stashFile, array_flip( $imParam ), $result );
2125                 } else {
2126                         $imParam = ApiQueryImageInfo::getPropertyNames();
2127                         $info = ApiQueryImageInfo::getInfo( $localFile, array_flip( $imParam ), $result );
2128                 }
2129
2130                 return $info;
2131         }
2132
2133         /**
2134          * @param array $error
2135          * @return Status
2136          */
2137         public function convertVerifyErrorToStatus( $error ) {
2138                 $code = $error['status'];
2139                 unset( $code['status'] );
2140
2141                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
2142         }
2143
2144         /**
2145          * Get the MediaWiki maximum uploaded file size for given type of upload, based on
2146          * $wgMaxUploadSize.
2147          *
2148          * @param null|string $forType
2149          * @return int
2150          */
2151         public static function getMaxUploadSize( $forType = null ) {
2152                 global $wgMaxUploadSize;
2153
2154                 if ( is_array( $wgMaxUploadSize ) ) {
2155                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
2156                                 return $wgMaxUploadSize[$forType];
2157                         } else {
2158                                 return $wgMaxUploadSize['*'];
2159                         }
2160                 } else {
2161                         return intval( $wgMaxUploadSize );
2162                 }
2163         }
2164
2165         /**
2166          * Get the PHP maximum uploaded file size, based on ini settings. If there is no limit or the
2167          * limit can't be guessed, returns a very large number (PHP_INT_MAX).
2168          *
2169          * @since 1.27
2170          * @return int
2171          */
2172         public static function getMaxPhpUploadSize() {
2173                 $phpMaxFileSize = wfShorthandToInteger(
2174                         ini_get( 'upload_max_filesize' ) ?: ini_get( 'hhvm.server.upload.upload_max_file_size' ),
2175                         PHP_INT_MAX
2176                 );
2177                 $phpMaxPostSize = wfShorthandToInteger(
2178                         ini_get( 'post_max_size' ) ?: ini_get( 'hhvm.server.max_post_size' ),
2179                         PHP_INT_MAX
2180                 ) ?: PHP_INT_MAX;
2181                 return min( $phpMaxFileSize, $phpMaxPostSize );
2182         }
2183
2184         /**
2185          * Get the current status of a chunked upload (used for polling)
2186          *
2187          * The value will be read from cache.
2188          *
2189          * @param User $user
2190          * @param string $statusKey
2191          * @return Status[]|bool
2192          */
2193         public static function getSessionStatus( User $user, $statusKey ) {
2194                 $cache = MediaWikiServices::getInstance()->getMainObjectStash();
2195                 $key = $cache->makeKey( 'uploadstatus', $user->getId() ?: md5( $user->getName() ), $statusKey );
2196
2197                 return $cache->get( $key );
2198         }
2199
2200         /**
2201          * Set the current status of a chunked upload (used for polling)
2202          *
2203          * The value will be set in cache for 1 day
2204          *
2205          * @param User $user
2206          * @param string $statusKey
2207          * @param array|bool $value
2208          * @return void
2209          */
2210         public static function setSessionStatus( User $user, $statusKey, $value ) {
2211                 $cache = MediaWikiServices::getInstance()->getMainObjectStash();
2212                 $key = $cache->makeKey( 'uploadstatus', $user->getId() ?: md5( $user->getName() ), $statusKey );
2213
2214                 if ( $value === false ) {
2215                         $cache->delete( $key );
2216                 } else {
2217                         $cache->set( $key, $value, $cache::TTL_DAY );
2218                 }
2219         }
2220 }