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;
 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                         # Check what Internet Explorer would detect
 416                         $fp = fopen( $this->mTempPath, 'rb' );
 417                         $chunk = fread( $fp, 256 );
 418                         fclose( $fp );
 419
 420                         $magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
 421                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 422                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 423                         foreach ( $ieTypes as $ieType ) {
 424                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 425                                         return [ 'filetype-bad-ie-mime', $ieType ];
 426                                 }
 427                         }
 428                 }
 429
 430                 return true;
 431         }
 432
 433         /**
 434          * Verifies that it's ok to include the uploaded file
 435          *
 436          * @return mixed True of the file is verified, array otherwise.
 437          */
 438         protected function verifyFile() {
 439                 global $wgVerifyMimeType, $wgDisableUploadScriptChecks;
 440
 441                 $status = $this->verifyPartialFile();
 442                 if ( $status !== true ) {
 443                         return $status;
 444                 }
 445
 446                 $mwProps = new MWFileProps( MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer() );
 447                 $this->mFileProps = $mwProps->getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 448                 $mime = $this->mFileProps['mime'];
 449
 450                 if ( $wgVerifyMimeType ) {
 451                         # XXX: Missing extension will be caught by validateName() via getTitle()
 452                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 453                                 return [ 'filetype-mime-mismatch', $this->mFinalExtension, $mime ];
 454                         }
 455                 }
 456
 457                 # check for htmlish code and javascript
 458                 if ( !$wgDisableUploadScriptChecks ) {
 459                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 460                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath, false );
 461                                 if ( $svgStatus !== false ) {
 462                                         return $svgStatus;
 463                                 }
 464                         }
 465                 }
 466
 467                 $handler = MediaHandler::getHandler( $mime );
 468                 if ( $handler ) {
 469                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 470                         if ( !$handlerStatus->isOK() ) {
 471                                 $errors = $handlerStatus->getErrorsArray();
 472
 473                                 return reset( $errors );
 474                         }
 475                 }
 476
 477                 $error = true;
 478                 Hooks::run( 'UploadVerifyFile', [ $this, $mime, &$error ] );
 479                 if ( $error !== true ) {
 480                         if ( !is_array( $error ) ) {
 481                                 $error = [ $error ];
 482                         }
 483                         return $error;
 484                 }
 485
 486                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 487
 488                 return true;
 489         }
 490
 491         /**
 492          * A verification routine suitable for partial files
 493          *
 494          * Runs the blacklist checks, but not any checks that may
 495          * assume the entire file is present.
 496          *
 497          * @return mixed True for valid or array with error message key.
 498          */
 499         protected function verifyPartialFile() {
 500                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 501
 502                 # getTitle() sets some internal parameters like $this->mFinalExtension
 503                 $this->getTitle();
 504
 505                 $mwProps = new MWFileProps( MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer() );
 506                 $this->mFileProps = $mwProps->getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 507
 508                 # check MIME type, if desired
 509                 $mime = $this->mFileProps['file-mime'];
 510                 $status = $this->verifyMimeType( $mime );
 511                 if ( $status !== true ) {
 512                         return $status;
 513                 }
 514
 515                 # check for htmlish code and javascript
 516                 if ( !$wgDisableUploadScriptChecks ) {
 517                         if ( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 518                                 return [ 'uploadscripted' ];
 519                         }
 520                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 521                                 $svgStatus = $this->detectScriptInSvg( $this->mTempPath, true );
 522                                 if ( $svgStatus !== false ) {
 523                                         return $svgStatus;
 524                                 }
 525                         }
 526                 }
 527
 528                 # Check for Java applets, which if uploaded can bypass cross-site
 529                 # restrictions.
 530                 if ( !$wgAllowJavaUploads ) {
 531                         $this->mJavaDetected = false;
 532                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 533                                 [ $this, 'zipEntryCallback' ] );
 534                         if ( !$zipStatus->isOK() ) {
 535                                 $errors = $zipStatus->getErrorsArray();
 536                                 $error = reset( $errors );
 537                                 if ( $error[0] !== 'zip-wrong-format' ) {
 538                                         return $error;
 539                                 }
 540                         }
 541                         if ( $this->mJavaDetected ) {
 542                                 return [ 'uploadjava' ];
 543                         }
 544                 }
 545
 546                 # Scan the uploaded file for viruses
 547                 $virus = $this->detectVirus( $this->mTempPath );
 548                 if ( $virus ) {
 549                         return [ 'uploadvirus', $virus ];
 550                 }
 551
 552                 return true;
 553         }
 554
 555         /**
 556          * Callback for ZipDirectoryReader to detect Java class files.
 557          *
 558          * @param array $entry
 559          */
 560         public function zipEntryCallback( $entry ) {
 561                 $names = [ $entry['name'] ];
 562
 563                 // If there is a null character, cut off the name at it, because JDK's
 564                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 565                 // were constructed which had ".class\0" followed by a string chosen to
 566                 // make the hash collide with the truncated name, that file could be
 567                 // returned in response to a request for the .class file.
 568                 $nullPos = strpos( $entry['name'], "\000" );
 569                 if ( $nullPos !== false ) {
 570                         $names[] = substr( $entry['name'], 0, $nullPos );
 571                 }
 572
 573                 // If there is a trailing slash in the file name, we have to strip it,
 574                 // because that's what ZIP_GetEntry() does.
 575                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 576                         $this->mJavaDetected = true;
 577                 }
 578         }
 579
 580         /**
 581          * Alias for verifyTitlePermissions. The function was originally
 582          * 'verifyPermissions', but that suggests it's checking the user, when it's
 583          * really checking the title + user combination.
 584          *
 585          * @param User $user User object to verify the permissions against
 586          * @return mixed An array as returned by getUserPermissionsErrors or true
 587          *   in case the user has proper permissions.
 588          */
 589         public function verifyPermissions( $user ) {
 590                 return $this->verifyTitlePermissions( $user );
 591         }
 592
 593         /**
 594          * Check whether the user can edit, upload and create the image. This
 595          * checks only against the current title; if it returns errors, it may
 596          * very well be that another title will not give errors. Therefore
 597          * isAllowed() should be called as well for generic is-user-blocked or
 598          * can-user-upload checking.
 599          *
 600          * @param User $user User object to verify the permissions against
 601          * @return mixed An array as returned by getUserPermissionsErrors or true
 602          *   in case the user has proper permissions.
 603          */
 604         public function verifyTitlePermissions( $user ) {
 605                 /**
 606                  * If the image is protected, non-sysop users won't be able
 607                  * to modify it by uploading a new revision.
 608                  */
 609                 $nt = $this->getTitle();
 610                 if ( is_null( $nt ) ) {
 611                         return true;
 612                 }
 613                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 614                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 615                 if ( !$nt->exists() ) {
 616                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 617                 } else {
 618                         $permErrorsCreate = [];
 619                 }
 620                 if ( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 621                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 622                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 623
 624                         return $permErrors;
 625                 }
 626
 627                 $overwriteError = $this->checkOverwrite( $user );
 628                 if ( $overwriteError !== true ) {
 629                         return [ $overwriteError ];
 630                 }
 631
 632                 return true;
 633         }
 634
 635         /**
 636          * Check for non fatal problems with the file.
 637          *
 638          * This should not assume that mTempPath is set.
 639          *
 640          * @return mixed[] Array of warnings
 641          */
 642         public function checkWarnings() {
 643                 $warnings = [];
 644
 645                 $localFile = $this->getLocalFile();
 646                 $localFile->load( File::READ_LATEST );
 647                 $filename = $localFile->getName();
 648                 $hash = $this->getTempFileSha1Base36();
 649
 650                 $badFileName = $this->checkBadFileName( $filename, $this->mDesiredDestName );
 651                 if ( $badFileName !== null ) {
 652                         $warnings['badfilename'] = $badFileName;
 653                 }
 654
 655                 $unwantedFileExtensionDetails = $this->checkUnwantedFileExtensions( $this->mFinalExtension );
 656                 if ( $unwantedFileExtensionDetails !== null ) {
 657                         $warnings['filetype-unwanted-type'] = $unwantedFileExtensionDetails;
 658                 }
 659
 660                 $fileSizeWarnings = $this->checkFileSize( $this->mFileSize );
 661                 if ( $fileSizeWarnings ) {
 662                         $warnings = array_merge( $warnings, $fileSizeWarnings );
 663                 }
 664
 665                 $localFileExistsWarnings = $this->checkLocalFileExists( $localFile, $hash );
 666                 if ( $localFileExistsWarnings ) {
 667                         $warnings = array_merge( $warnings, $localFileExistsWarnings );
 668                 }
 669
 670                 if ( $this->checkLocalFileWasDeleted( $localFile ) ) {
 671                         $warnings['was-deleted'] = $filename;
 672                 }
 673
 674                 // If a file with the same name exists locally then the local file has already been tested
 675                 // for duplication of content
 676                 $ignoreLocalDupes = isset( $warnings[ 'exists '] );
 677                 $dupes = $this->checkAgainstExistingDupes( $hash, $ignoreLocalDupes );
 678                 if ( $dupes ) {
 679                         $warnings['duplicate'] = $dupes;
 680                 }
 681
 682                 $archivedDupes = $this->checkAgainstArchiveDupes( $hash );
 683                 if ( $archivedDupes !== null ) {
 684                         $warnings['duplicate-archive'] = $archivedDupes;
 685                 }
 686
 687                 return $warnings;
 688         }
 689
 690         /**
 691          * Check whether the resulting filename is different from the desired one,
 692          * but ignore things like ucfirst() and spaces/underscore things
 693          *
 694          * @param string $filename
 695          * @param string $desiredFileName
 696          *
 697          * @return string|null String that was determined to be bad or null if the filename is okay
 698          */
 699         private function checkBadFileName( $filename, $desiredFileName ) {
 700                 $comparableName = str_replace( ' ', '_', $desiredFileName );
 701                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 702
 703                 if ( $desiredFileName != $filename && $comparableName != $filename ) {
 704                         return $filename;
 705                 }
 706
 707                 return null;
 708         }
 709
 710         /**
 711          * @param string $fileExtension The file extension to check
 712          *
 713          * @return array|null array with the following keys:
 714          *                    0 => string The final extension being used
 715          *                    1 => string[] The extensions that are allowed
 716          *                    2 => int The number of extensions that are allowed.
 717          */
 718         private function checkUnwantedFileExtensions( $fileExtension ) {
 719                 global $wgCheckFileExtensions, $wgFileExtensions, $wgLang;
 720
 721                 if ( $wgCheckFileExtensions ) {
 722                         $extensions = array_unique( $wgFileExtensions );
 723                         if ( !$this->checkFileExtension( $fileExtension, $extensions ) ) {
 724                                 return [
 725                                         $fileExtension,
 726                                         $wgLang->commaList( $extensions ),
 727                                         count( $extensions )
 728                                 ];
 729                         }
 730                 }
 731
 732                 return null;
 733         }
 734
 735         /**
 736          * @param int $fileSize
 737          *
 738          * @return array warnings
 739          */
 740         private function checkFileSize( $fileSize ) {
 741                 global $wgUploadSizeWarning;
 742
 743                 $warnings = [];
 744
 745                 if ( $wgUploadSizeWarning && ( $fileSize > $wgUploadSizeWarning ) ) {
 746                         $warnings['large-file'] = [ $wgUploadSizeWarning, $fileSize ];
 747                 }
 748
 749                 if ( $fileSize == 0 ) {
 750                         $warnings['empty-file'] = true;
 751                 }
 752
 753                 return $warnings;
 754         }
 755
 756         /**
 757          * @param LocalFile $localFile
 758          * @param string $hash sha1 hash of the file to check
 759          *
 760          * @return array warnings
 761          */
 762         private function checkLocalFileExists( LocalFile $localFile, $hash ) {
 763                 $warnings = [];
 764
 765                 $exists = self::getExistsWarning( $localFile );
 766                 if ( $exists !== false ) {
 767                         $warnings['exists'] = $exists;
 768
 769                         // check if file is an exact duplicate of current file version
 770                         if ( $hash === $localFile->getSha1() ) {
 771                                 $warnings['no-change'] = $localFile;
 772                         }
 773
 774                         // check if file is an exact duplicate of older versions of this file
 775                         $history = $localFile->getHistory();
 776                         foreach ( $history as $oldFile ) {
 777                                 if ( $hash === $oldFile->getSha1() ) {
 778                                         $warnings['duplicate-version'][] = $oldFile;
 779                                 }
 780                         }
 781                 }
 782
 783                 return $warnings;
 784         }
 785
 786         private function checkLocalFileWasDeleted( LocalFile $localFile ) {
 787                 return $localFile->wasDeleted() && !$localFile->exists();
 788         }
 789
 790         /**
 791          * @param string $hash sha1 hash of the file to check
 792          * @param bool $ignoreLocalDupes True to ignore local duplicates
 793          *
 794          * @return File[] Duplicate files, if found.
 795          */
 796         private function checkAgainstExistingDupes( $hash, $ignoreLocalDupes ) {
 797                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 798                 $title = $this->getTitle();
 799                 foreach ( $dupes as $key => $dupe ) {
 800                         if (
 801                                 ( $dupe instanceof LocalFile ) &&
 802                                 $ignoreLocalDupes &&
 803                                 $title->equals( $dupe->getTitle() )
 804                         ) {
 805                                 unset( $dupes[$key] );
 806                         }
 807                 }
 808
 809                 return $dupes;
 810         }
 811
 812         /**
 813          * @param string $hash sha1 hash of the file to check
 814          *
 815          * @return string|null Name of the dupe or empty string if discovered (depending on visibility)
 816          *                     null if the check discovered no dupes.
 817          */
 818         private function checkAgainstArchiveDupes( $hash ) {
 819                 $archivedFile = new ArchivedFile( null, 0, '', $hash );
 820                 if ( $archivedFile->getID() > 0 ) {
 821                         if ( $archivedFile->userCan( File::DELETED_FILE ) ) {
 822                                 return $archivedFile->getName();
 823                         } else {
 824                                 return '';
 825                         }
 826                 }
 827
 828                 return null;
 829         }
 830
 831         /**
 832          * Really perform the upload. Stores the file in the local repo, watches
 833          * if necessary and runs the UploadComplete hook.
 834          *
 835          * @param string $comment
 836          * @param string $pageText
 837          * @param bool $watch Whether the file page should be added to user's watchlist.
 838          *   (This doesn't check $user's permissions.)
 839          * @param User $user
 840          * @param string[] $tags Change tags to add to the log entry and page revision.
 841          *   (This doesn't check $user's permissions.)
 842          * @return Status Indicating the whether the upload succeeded.
 843          */
 844         public function performUpload( $comment, $pageText, $watch, $user, $tags = [] ) {
 845                 $this->getLocalFile()->load( File::READ_LATEST );
 846                 $props = $this->mFileProps;
 847
 848                 $error = null;
 849                 Hooks::run( 'UploadVerifyUpload', [ $this, $user, $props, $comment, $pageText, &$error ] );
 850                 if ( $error ) {
 851                         if ( !is_array( $error ) ) {
 852                                 $error = [ $error ];
 853                         }
 854                         return Status::newFatal( ...$error );
 855                 }
 856
 857                 $status = $this->getLocalFile()->upload(
 858                         $this->mTempPath,
 859                         $comment,
 860                         $pageText,
 861                         File::DELETE_SOURCE,
 862                         $props,
 863                         false,
 864                         $user,
 865                         $tags
 866                 );
 867
 868                 if ( $status->isGood() ) {
 869                         if ( $watch ) {
 870                                 WatchAction::doWatch(
 871                                         $this->getLocalFile()->getTitle(),
 872                                         $user,
 873                                         User::IGNORE_USER_RIGHTS
 874                                 );
 875                         }
 876                         // Avoid PHP 7.1 warning of passing $this by reference
 877                         $uploadBase = $this;
 878                         Hooks::run( 'UploadComplete', [ &$uploadBase ] );
 879
 880                         $this->postProcessUpload();
 881                 }
 882
 883                 return $status;
 884         }
 885
 886         /**
 887          * Perform extra steps after a successful upload.
 888          *
 889          * @since  1.25
 890          */
 891         public function postProcessUpload() {
 892         }
 893
 894         /**
 895          * Returns the title of the file to be uploaded. Sets mTitleError in case
 896          * the name was illegal.
 897          *
 898          * @return Title|null The title of the file or null in case the name was illegal
 899          */
 900         public function getTitle() {
 901                 if ( $this->mTitle !== false ) {
 902                         return $this->mTitle;
 903                 }
 904                 if ( !is_string( $this->mDesiredDestName ) ) {
 905                         $this->mTitleError = self::ILLEGAL_FILENAME;
 906                         $this->mTitle = null;
 907
 908                         return $this->mTitle;
 909                 }
 910                 /* Assume that if a user specified File:Something.jpg, this is an error
 911                  * and that the namespace prefix needs to be stripped of.
 912                  */
 913                 $title = Title::newFromText( $this->mDesiredDestName );
 914                 if ( $title && $title->getNamespace() == NS_FILE ) {
 915                         $this->mFilteredName = $title->getDBkey();
 916                 } else {
 917                         $this->mFilteredName = $this->mDesiredDestName;
 918                 }
 919
 920                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 921                 # exclamation mark, so restrict file name to 240 bytes.
 922                 if ( strlen( $this->mFilteredName ) > 240 ) {
 923                         $this->mTitleError = self::FILENAME_TOO_LONG;
 924                         $this->mTitle = null;
 925
 926                         return $this->mTitle;
 927                 }
 928
 929                 /**
 930                  * Chop off any directories in the given filename. Then
 931                  * filter out illegal characters, and try to make a legible name
 932                  * out of it. We'll strip some silently that Title would die on.
 933                  */
 934                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 935                 /* Normalize to title form before we do any further processing */
 936                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 937                 if ( is_null( $nt ) ) {
 938                         $this->mTitleError = self::ILLEGAL_FILENAME;
 939                         $this->mTitle = null;
 940
 941                         return $this->mTitle;
 942                 }
 943                 $this->mFilteredName = $nt->getDBkey();
 944
 945                 /**
 946                  * We'll want to blacklist against *any* 'extension', and use
 947                  * only the final one for the whitelist.
 948                  */
 949                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 950
 951                 if ( $ext !== [] ) {
 952                         $this->mFinalExtension = trim( end( $ext ) );
 953                 } else {
 954                         $this->mFinalExtension = '';
 955
 956                         # No extension, try guessing one
 957                         $magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
 958                         $mime = $magic->guessMimeType( $this->mTempPath );
 959                         if ( $mime !== 'unknown/unknown' ) {
 960                                 # Get a space separated list of extensions
 961                                 $extList = $magic->getExtensionsForType( $mime );
 962                                 if ( $extList ) {
 963                                         # Set the extension to the canonical extension
 964                                         $this->mFinalExtension = strtok( $extList, ' ' );
 965
 966                                         # Fix up the other variables
 967                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 968                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 969                                         $ext = [ $this->mFinalExtension ];
 970                                 }
 971                         }
 972                 }
 973
 974                 /* Don't allow users to override the blacklist (check file extension) */
 975                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 976                 global $wgFileExtensions, $wgFileBlacklist;
 977
 978                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 979
 980                 if ( $this->mFinalExtension == '' ) {
 981                         $this->mTitleError = self::FILETYPE_MISSING;
 982                         $this->mTitle = null;
 983
 984                         return $this->mTitle;
 985                 } elseif ( $blackListedExtensions ||
 986                         ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 987                                 !$this->checkFileExtension( $this->mFinalExtension, $wgFileExtensions ) )
 988                 ) {
 989                         $this->mBlackListedExtensions = $blackListedExtensions;
 990                         $this->mTitleError = self::FILETYPE_BADTYPE;
 991                         $this->mTitle = null;
 992
 993                         return $this->mTitle;
 994                 }
 995
 996                 // Windows may be broken with special characters, see T3780
 997                 if ( !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() )
 998                         && !RepoGroup::singleton()->getLocalRepo()->backendSupportsUnicodePaths()
 999                 ) {
1000                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
1001                         $this->mTitle = null;
1002
1003                         return $this->mTitle;
1004                 }
1005
1006                 # If there was more than one "extension", reassemble the base
1007                 # filename to prevent bogus complaints about length
1008                 if ( count( $ext ) > 1 ) {
1009                         $iterations = count( $ext ) - 1;
1010                         for ( $i = 0; $i < $iterations; $i++ ) {
1011                                 $partname .= '.' . $ext[$i];
1012                         }
1013                 }
1014
1015                 if ( strlen( $partname ) < 1 ) {
1016                         $this->mTitleError = self::MIN_LENGTH_PARTNAME;
1017                         $this->mTitle = null;
1018
1019                         return $this->mTitle;
1020                 }
1021
1022                 $this->mTitle = $nt;
1023
1024                 return $this->mTitle;
1025         }
1026
1027         /**
1028          * Return the local file and initializes if necessary.
1029          *
1030          * @return LocalFile|null
1031          */
1032         public function getLocalFile() {
1033                 if ( is_null( $this->mLocalFile ) ) {
1034                         $nt = $this->getTitle();
1035                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
1036                 }
1037
1038                 return $this->mLocalFile;
1039         }
1040
1041         /**
1042          * @return UploadStashFile|null
1043          */
1044         public function getStashFile() {
1045                 return $this->mStashFile;
1046         }
1047
1048         /**
1049          * Like stashFile(), but respects extensions' wishes to prevent the stashing. verifyUpload() must
1050          * be called before calling this method (unless $isPartial is true).
1051          *
1052          * Upload stash exceptions are also caught and converted to an error status.
1053          *
1054          * @since 1.28
1055          * @param User $user
1056          * @param bool $isPartial Pass `true` if this is a part of a chunked upload (not a complete file).
1057          * @return Status If successful, value is an UploadStashFile instance
1058          */
1059         public function tryStashFile( User $user, $isPartial = false ) {
1060                 if ( !$isPartial ) {
1061                         $error = $this->runUploadStashFileHook( $user );
1062                         if ( $error ) {
1063                                 return Status::newFatal( ...$error );
1064                         }
1065                 }
1066                 try {
1067                         $file = $this->doStashFile( $user );
1068                         return Status::newGood( $file );
1069                 } catch ( UploadStashException $e ) {
1070                         return Status::newFatal( 'uploadstash-exception', get_class( $e ), $e->getMessage() );
1071                 }
1072         }
1073
1074         /**
1075          * @param User $user
1076          * @return array|null Error message and parameters, null if there's no error
1077          */
1078         protected function runUploadStashFileHook( User $user ) {
1079                 $props = $this->mFileProps;
1080                 $error = null;
1081                 Hooks::run( 'UploadStashFile', [ $this, $user, $props, &$error ] );
1082                 if ( $error && !is_array( $error ) ) {
1083                         $error = [ $error ];
1084                 }
1085                 return $error;
1086         }
1087
1088         /**
1089          * If the user does not supply all necessary information in the first upload
1090          * form submission (either by accident or by design) then we may want to
1091          * stash the file temporarily, get more information, and publish the file
1092          * later.
1093          *
1094          * This method will stash a file in a temporary directory for later
1095          * processing, and save the necessary descriptive info into the database.
1096          * This method returns the file object, which also has a 'fileKey' property
1097          * which can be passed through a form or API request to find this stashed
1098          * file again.
1099          *
1100          * @deprecated since 1.28 Use tryStashFile() instead
1101          * @param User|null $user
1102          * @return UploadStashFile Stashed file
1103          * @throws UploadStashBadPathException
1104          * @throws UploadStashFileException
1105          * @throws UploadStashNotLoggedInException
1106          */
1107         public function stashFile( User $user = null ) {
1108                 return $this->doStashFile( $user );
1109         }
1110
1111         /**
1112          * Implementation for stashFile() and tryStashFile().
1113          *
1114          * @param User|null $user
1115          * @return UploadStashFile Stashed file
1116          */
1117         protected function doStashFile( User $user = null ) {
1118                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $user );
1119                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
1120                 $this->mStashFile = $file;
1121
1122                 return $file;
1123         }
1124
1125         /**
1126          * Stash a file in a temporary directory, returning a key which can be used
1127          * to find the file again. See stashFile().
1128          *
1129          * @deprecated since 1.28
1130          * @return string File key
1131          */
1132         public function stashFileGetKey() {
1133                 wfDeprecated( __METHOD__, '1.28' );
1134                 return $this->doStashFile()->getFileKey();
1135         }
1136
1137         /**
1138          * alias for stashFileGetKey, for backwards compatibility
1139          *
1140          * @deprecated since 1.28
1141          * @return string File key
1142          */
1143         public function stashSession() {
1144                 wfDeprecated( __METHOD__, '1.28' );
1145                 return $this->doStashFile()->getFileKey();
1146         }
1147
1148         /**
1149          * If we've modified the upload file we need to manually remove it
1150          * on exit to clean up.
1151          */
1152         public function cleanupTempFile() {
1153                 if ( $this->mRemoveTempFile && $this->tempFileObj ) {
1154                         // Delete when all relevant TempFSFile handles go out of scope
1155                         wfDebug( __METHOD__ . ": Marked temporary file '{$this->mTempPath}' for removal\n" );
1156                         $this->tempFileObj->autocollect();
1157                 }
1158         }
1159
1160         public function getTempPath() {
1161                 return $this->mTempPath;
1162         }
1163
1164         /**
1165          * Split a file into a base name and all dot-delimited 'extensions'
1166          * on the end. Some web server configurations will fall back to
1167          * earlier pseudo-'extensions' to determine type and execute
1168          * scripts, so the blacklist needs to check them all.
1169          *
1170          * @param string $filename
1171          * @return array [ string, string[] ]
1172          */
1173         public static function splitExtensions( $filename ) {
1174                 $bits = explode( '.', $filename );
1175                 $basename = array_shift( $bits );
1176
1177                 return [ $basename, $bits ];
1178         }
1179
1180         /**
1181          * Perform case-insensitive match against a list of file extensions.
1182          * Returns true if the extension is in the list.
1183          *
1184          * @param string $ext
1185          * @param array $list
1186          * @return bool
1187          */
1188         public static function checkFileExtension( $ext, $list ) {
1189                 return in_array( strtolower( $ext ), $list );
1190         }
1191
1192         /**
1193          * Perform case-insensitive match against a list of file extensions.
1194          * Returns an array of matching extensions.
1195          *
1196          * @param string[] $ext
1197          * @param string[] $list
1198          * @return string[]
1199          */
1200         public static function checkFileExtensionList( $ext, $list ) {
1201                 return array_intersect( array_map( 'strtolower', $ext ), $list );
1202         }
1203
1204         /**
1205          * Checks if the MIME type of the uploaded file matches the file extension.
1206          *
1207          * @param string $mime The MIME type of the uploaded file
1208          * @param string $extension The filename extension that the file is to be served with
1209          * @return bool
1210          */
1211         public static function verifyExtension( $mime, $extension ) {
1212                 $magic = MediaWiki\MediaWikiServices::getInstance()->getMimeAnalyzer();
1213
1214                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' ) {
1215                         if ( !$magic->isRecognizableExtension( $extension ) ) {
1216                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
1217                                         "unrecognized extension '$extension', can't verify\n" );
1218
1219                                 return true;
1220                         } else {
1221                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; " .
1222                                         "recognized extension '$extension', so probably invalid file\n" );
1223
1224                                 return false;
1225                         }
1226                 }
1227
1228                 $match = $magic->isMatchingExtension( $extension, $mime );
1229
1230                 if ( $match === null ) {
1231                         if ( $magic->getTypesForExtension( $extension ) !== null ) {
1232                                 wfDebug( __METHOD__ . ": No extension known for $mime, but we know a mime for $extension\n" );
1233
1234                                 return false;
1235                         } else {
1236                                 wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
1237
1238                                 return true;
1239                         }
1240                 } elseif ( $match === true ) {
1241                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
1242
1243                         /** @todo If it's a bitmap, make sure PHP or ImageMagick resp. can handle it! */
1244                         return true;
1245                 } else {
1246                         wfDebug( __METHOD__
1247                                 . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
1248
1249                         return false;
1250                 }
1251         }
1252
1253         /**
1254          * Heuristic for detecting files that *could* contain JavaScript instructions or
1255          * things that may look like HTML to a browser and are thus
1256          * potentially harmful. The present implementation will produce false
1257          * positives in some situations.
1258          *
1259          * @param string $file Pathname to the temporary upload file
1260          * @param string $mime The MIME type of the file
1261          * @param string $extension The extension of the file
1262          * @return bool True if the file contains something looking like embedded scripts
1263          */
1264         public static function detectScript( $file, $mime, $extension ) {
1265                 global $wgAllowTitlesInSVG;
1266
1267                 # ugly hack: for text files, always look at the entire file.
1268                 # For binary field, just check the first K.
1269
1270                 if ( strpos( $mime, 'text/' ) === 0 ) {
1271                         $chunk = file_get_contents( $file );
1272                 } else {
1273                         $fp = fopen( $file, 'rb' );
1274                         $chunk = fread( $fp, 1024 );
1275                         fclose( $fp );
1276                 }
1277
1278                 $chunk = strtolower( $chunk );
1279
1280                 if ( !$chunk ) {
1281                         return false;
1282                 }
1283
1284                 # decode from UTF-16 if needed (could be used for obfuscation).
1285                 if ( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
1286                         $enc = 'UTF-16BE';
1287                 } elseif ( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
1288                         $enc = 'UTF-16LE';
1289                 } else {
1290                         $enc = null;
1291                 }
1292
1293                 if ( $enc ) {
1294                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
1295                 }
1296
1297                 $chunk = trim( $chunk );
1298
1299                 /** @todo FIXME: Convert from UTF-16 if necessary! */
1300                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
1301
1302                 # check for HTML doctype
1303                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
1304                         return true;
1305                 }
1306
1307                 // Some browsers will interpret obscure xml encodings as UTF-8, while
1308                 // PHP/expat will interpret the given encoding in the xml declaration (T49304)
1309                 if ( $extension == 'svg' || strpos( $mime, 'image/svg' ) === 0 ) {
1310                         if ( self::checkXMLEncodingMissmatch( $file ) ) {
1311                                 return true;
1312                         }
1313                 }
1314
1315                 /**
1316                  * Internet Explorer for Windows performs some really stupid file type
1317                  * autodetection which can cause it to interpret valid image files as HTML
1318                  * and potentially execute JavaScript, creating a cross-site scripting
1319                  * attack vectors.
1320                  *
1321                  * Apple's Safari browser also performs some unsafe file type autodetection
1322                  * which can cause legitimate files to be interpreted as HTML if the
1323                  * web server is not correctly configured to send the right content-type
1324                  * (or if you're really uploading plain text and octet streams!)
1325                  *
1326                  * Returns true if IE is likely to mistake the given file for HTML.
1327                  * Also returns true if Safari would mistake the given file for HTML
1328                  * when served with a generic content-type.
1329                  */
1330                 $tags = [
1331                         '<a href',
1332                         '<body',
1333                         '<head',
1334                         '<html', # also in safari
1335                         '<img',
1336                         '<pre',
1337                         '<script', # also in safari
1338                         '<table'
1339                 ];
1340
1341                 if ( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
1342                         $tags[] = '<title';
1343                 }
1344
1345                 foreach ( $tags as $tag ) {
1346                         if ( strpos( $chunk, $tag ) !== false ) {
1347                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1348
1349                                 return true;
1350                         }
1351                 }
1352
1353                 /*
1354                  * look for JavaScript
1355                  */
1356
1357                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1358                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1359
1360                 # look for script-types
1361                 if ( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1362                         wfDebug( __METHOD__ . ": found script types\n" );
1363
1364                         return true;
1365                 }
1366
1367                 # look for html-style script-urls
1368                 if ( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1369                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1370
1371                         return true;
1372                 }
1373
1374                 # look for css-style script-urls
1375                 if ( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1376                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1377
1378                         return true;
1379                 }
1380
1381                 wfDebug( __METHOD__ . ": no scripts found\n" );
1382
1383                 return false;
1384         }
1385
1386         /**
1387          * Check a whitelist of xml encodings that are known not to be interpreted differently
1388          * by the server's xml parser (expat) and some common browsers.
1389          *
1390          * @param string $file Pathname to the temporary upload file
1391          * @return bool True if the file contains an encoding that could be misinterpreted
1392          */
1393         public static function checkXMLEncodingMissmatch( $file ) {
1394                 global $wgSVGMetadataCutoff;
1395                 $contents = file_get_contents( $file, false, null, 0, $wgSVGMetadataCutoff );
1396                 $encodingRegex = '!encoding[ \t\n\r]*=[ \t\n\r]*[\'"](.*?)[\'"]!si';
1397
1398                 if ( preg_match( "!<\?xml\b(.*?)\?>!si", $contents, $matches ) ) {
1399                         if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1400                                 && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1401                         ) {
1402                                 wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1403
1404                                 return true;
1405                         }
1406                 } elseif ( preg_match( "!<\?xml\b!si", $contents ) ) {
1407                         // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1408                         // bytes. There shouldn't be a legitimate reason for this to happen.
1409                         wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1410
1411                         return true;
1412                 } elseif ( substr( $contents, 0, 4 ) == "\x4C\x6F\xA7\x94" ) {
1413                         // EBCDIC encoded XML
1414                         wfDebug( __METHOD__ . ": EBCDIC Encoded XML\n" );
1415
1416                         return true;
1417                 }
1418
1419                 // It's possible the file is encoded with multi-byte encoding, so re-encode attempt to
1420                 // detect the encoding in case is specifies an encoding not whitelisted in self::$safeXmlEncodings
1421                 $attemptEncodings = [ 'UTF-16', 'UTF-16BE', 'UTF-32', 'UTF-32BE' ];
1422                 foreach ( $attemptEncodings as $encoding ) {
1423                         Wikimedia\suppressWarnings();
1424                         $str = iconv( $encoding, 'UTF-8', $contents );
1425                         Wikimedia\restoreWarnings();
1426                         if ( $str != '' && preg_match( "!<\?xml\b(.*?)\?>!si", $str, $matches ) ) {
1427                                 if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1428                                         && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1429                                 ) {
1430                                         wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1431
1432                                         return true;
1433                                 }
1434                         } elseif ( $str != '' && preg_match( "!<\?xml\b!si", $str ) ) {
1435                                 // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1436                                 // bytes. There shouldn't be a legitimate reason for this to happen.
1437                                 wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1438
1439                                 return true;
1440                         }
1441                 }
1442
1443                 return false;
1444         }
1445
1446         /**
1447          * @param string $filename
1448          * @param bool $partial
1449          * @return bool|array
1450          */
1451         protected function detectScriptInSvg( $filename, $partial ) {
1452                 $this->mSVGNSError = false;
1453                 $check = new XmlTypeCheck(
1454                         $filename,
1455                         [ $this, 'checkSvgScriptCallback' ],
1456                         true,
1457                         [
1458                                 'processing_instruction_handler' => 'UploadBase::checkSvgPICallback',
1459                                 'external_dtd_handler' => 'UploadBase::checkSvgExternalDTD',
1460                         ]
1461                 );
1462                 if ( $check->wellFormed !== true ) {
1463                         // Invalid xml (T60553)
1464                         // But only when non-partial (T67724)
1465                         return $partial ? false : [ 'uploadinvalidxml' ];
1466                 } elseif ( $check->filterMatch ) {
1467                         if ( $this->mSVGNSError ) {
1468                                 return [ 'uploadscriptednamespace', $this->mSVGNSError ];
1469                         }
1470
1471                         return $check->filterMatchType;
1472                 }
1473
1474                 return false;
1475         }
1476
1477         /**
1478          * Callback to filter SVG Processing Instructions.
1479          * @param string $target Processing instruction name
1480          * @param string $data Processing instruction attribute and value
1481          * @return bool|array
1482          */
1483         public static function checkSvgPICallback( $target, $data ) {
1484                 // Don't allow external stylesheets (T59550)
1485                 if ( preg_match( '/xml-stylesheet/i', $target ) ) {
1486                         return [ 'upload-scripted-pi-callback' ];
1487                 }
1488
1489                 return false;
1490         }
1491
1492         /**
1493          * Verify that DTD urls referenced are only the standard dtds
1494          *
1495          * Browsers seem to ignore external dtds. However just to be on the
1496          * safe side, only allow dtds from the svg standard.
1497          *
1498          * @param string $type PUBLIC or SYSTEM
1499          * @param string $publicId The well-known public identifier for the dtd
1500          * @param string $systemId The url for the external dtd
1501          * @return bool|array
1502          */
1503         public static function checkSvgExternalDTD( $type, $publicId, $systemId ) {
1504                 // This doesn't include the XHTML+MathML+SVG doctype since we don't
1505                 // allow XHTML anyways.
1506                 $allowedDTDs = [
1507                         'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd',
1508                         'http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd',
1509                         'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-basic.dtd',
1510                         'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-tiny.dtd',
1511                         // https://phabricator.wikimedia.org/T168856
1512                         'http://www.w3.org/TR/2001/PR-SVG-20010719/DTD/svg10.dtd',
1513                 ];
1514                 if ( $type !== 'PUBLIC'
1515                         || !in_array( $systemId, $allowedDTDs )
1516                         || strpos( $publicId, "-//W3C//" ) !== 0
1517                 ) {
1518                         return [ 'upload-scripted-dtd' ];
1519                 }
1520                 return false;
1521         }
1522
1523         /**
1524          * @todo Replace this with a whitelist filter!
1525          * @param string $element
1526          * @param array $attribs
1527          * @param array|null $data
1528          * @return bool|array
1529          */
1530         public function checkSvgScriptCallback( $element, $attribs, $data = null ) {
1531                 list( $namespace, $strippedElement ) = $this->splitXmlNamespace( $element );
1532
1533                 // We specifically don't include:
1534                 // http://www.w3.org/1999/xhtml (T62771)
1535                 static $validNamespaces = [
1536                         '',
1537                         'adobe:ns:meta/',
1538                         'http://creativecommons.org/ns#',
1539                         'http://inkscape.sourceforge.net/dtd/sodipodi-0.dtd',
1540                         'http://ns.adobe.com/adobeillustrator/10.0/',
1541                         'http://ns.adobe.com/adobesvgviewerextensions/3.0/',
1542                         'http://ns.adobe.com/extensibility/1.0/',
1543                         'http://ns.adobe.com/flows/1.0/',
1544                         'http://ns.adobe.com/illustrator/1.0/',
1545                         'http://ns.adobe.com/imagereplacement/1.0/',
1546                         'http://ns.adobe.com/pdf/1.3/',
1547                         'http://ns.adobe.com/photoshop/1.0/',
1548                         'http://ns.adobe.com/saveforweb/1.0/',
1549                         'http://ns.adobe.com/variables/1.0/',
1550                         'http://ns.adobe.com/xap/1.0/',
1551                         'http://ns.adobe.com/xap/1.0/g/',
1552                         'http://ns.adobe.com/xap/1.0/g/img/',
1553                         'http://ns.adobe.com/xap/1.0/mm/',
1554                         'http://ns.adobe.com/xap/1.0/rights/',
1555                         'http://ns.adobe.com/xap/1.0/stype/dimensions#',
1556                         'http://ns.adobe.com/xap/1.0/stype/font#',
1557                         'http://ns.adobe.com/xap/1.0/stype/manifestitem#',
1558                         'http://ns.adobe.com/xap/1.0/stype/resourceevent#',
1559                         'http://ns.adobe.com/xap/1.0/stype/resourceref#',
1560                         'http://ns.adobe.com/xap/1.0/t/pg/',
1561                         'http://purl.org/dc/elements/1.1/',
1562                         'http://purl.org/dc/elements/1.1',
1563                         'http://schemas.microsoft.com/visio/2003/svgextensions/',
1564                         'http://sodipodi.sourceforge.net/dtd/sodipodi-0.dtd',
1565                         'http://taptrix.com/inkpad/svg_extensions',
1566                         'http://web.resource.org/cc/',
1567                         'http://www.freesoftware.fsf.org/bkchem/cdml',
1568                         'http://www.inkscape.org/namespaces/inkscape',
1569                         'http://www.opengis.net/gml',
1570                         'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
1571                         'http://www.w3.org/2000/svg',
1572                         'http://www.w3.org/tr/rec-rdf-syntax/',
1573                         'http://www.w3.org/2000/01/rdf-schema#',
1574                 ];
1575
1576                 // Inkscape mangles namespace definitions created by Adobe Illustrator.
1577                 // This is nasty but harmless. (T144827)
1578                 $isBuggyInkscape = preg_match( '/^&(#38;)*ns_[a-z_]+;$/', $namespace );
1579
1580                 if ( !( $isBuggyInkscape || in_array( $namespace, $validNamespaces ) ) ) {
1581                         wfDebug( __METHOD__ . ": Non-svg namespace '$namespace' in uploaded file.\n" );
1582                         /** @todo Return a status object to a closure in XmlTypeCheck, for MW1.21+ */
1583                         $this->mSVGNSError = $namespace;
1584
1585                         return true;
1586                 }
1587
1588                 /*
1589                  * check for elements that can contain javascript
1590                  */
1591                 if ( $strippedElement == 'script' ) {
1592                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1593
1594                         return [ 'uploaded-script-svg', $strippedElement ];
1595                 }
1596
1597                 # e.g., <svg xmlns="http://www.w3.org/2000/svg">
1598                 #  <handler xmlns:ev="http://www.w3.org/2001/xml-events" ev:event="load">alert(1)</handler> </svg>
1599                 if ( $strippedElement == 'handler' ) {
1600                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1601
1602                         return [ 'uploaded-script-svg', $strippedElement ];
1603                 }
1604
1605                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1606                 if ( $strippedElement == 'stylesheet' ) {
1607                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1608
1609                         return [ 'uploaded-script-svg', $strippedElement ];
1610                 }
1611
1612                 # Block iframes, in case they pass the namespace check
1613                 if ( $strippedElement == 'iframe' ) {
1614                         wfDebug( __METHOD__ . ": iframe in uploaded file.\n" );
1615
1616                         return [ 'uploaded-script-svg', $strippedElement ];
1617                 }
1618
1619                 # Check <style> css
1620                 if ( $strippedElement == 'style'
1621                         && self::checkCssFragment( Sanitizer::normalizeCss( $data ) )
1622                 ) {
1623                         wfDebug( __METHOD__ . ": hostile css in style element.\n" );
1624                         return [ 'uploaded-hostile-svg' ];
1625                 }
1626
1627                 foreach ( $attribs as $attrib => $value ) {
1628                         $stripped = $this->stripXmlNamespace( $attrib );
1629                         $value = strtolower( $value );
1630
1631                         if ( substr( $stripped, 0, 2 ) == 'on' ) {
1632                                 wfDebug( __METHOD__
1633                                         . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1634
1635                                 return [ 'uploaded-event-handler-on-svg', $attrib, $value ];
1636                         }
1637
1638                         # Do not allow relative links, or unsafe url schemas.
1639                         # For <a> tags, only data:, http: and https: and same-document
1640                         # fragment links are allowed. For all other tags, only data:
1641                         # and fragment are allowed.
1642                         if ( $stripped == 'href'
1643                                 && $value !== ''
1644                                 && strpos( $value, 'data:' ) !== 0
1645                                 && strpos( $value, '#' ) !== 0
1646                         ) {
1647                                 if ( !( $strippedElement === 'a'
1648                                         && preg_match( '!^https?://!i', $value ) )
1649                                 ) {
1650                                         wfDebug( __METHOD__ . ": Found href attribute <$strippedElement "
1651                                                 . "'$attrib'='$value' in uploaded file.\n" );
1652
1653                                         return [ 'uploaded-href-attribute-svg', $strippedElement, $attrib, $value ];
1654                                 }
1655                         }
1656
1657                         # only allow data: targets that should be safe. This prevents vectors like,
1658                         # image/svg, text/xml, application/xml, and text/html, which can contain scripts
1659                         if ( $stripped == 'href' && strncasecmp( 'data:', $value, 5 ) === 0 ) {
1660                                 // rfc2397 parameters. This is only slightly slower than (;[\w;]+)*.
1661                                 // phpcs:ignore Generic.Files.LineLength
1662                                 $parameters = '(?>;[a-zA-Z0-9\!#$&\'*+.^_`{|}~-]+=(?>[a-zA-Z0-9\!#$&\'*+.^_`{|}~-]+|"(?>[\0-\x0c\x0e-\x21\x23-\x5b\x5d-\x7f]+|\\\\[\0-\x7f])*"))*(?:;base64)?';
1663
1664                                 if ( !preg_match( "!^data:\s*image/(gif|jpeg|jpg|png)$parameters,!i", $value ) ) {
1665                                         wfDebug( __METHOD__ . ": Found href to unwhitelisted data: uri "
1666                                                 . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1667                                         return [ 'uploaded-href-unsafe-target-svg', $strippedElement, $attrib, $value ];
1668                                 }
1669                         }
1670
1671                         # Change href with animate from (http://html5sec.org/#137).
1672                         if ( $stripped === 'attributename'
1673                                 && $strippedElement === 'animate'
1674                                 && $this->stripXmlNamespace( $value ) == 'href'
1675                         ) {
1676                                 wfDebug( __METHOD__ . ": Found animate that might be changing href using from "
1677                                         . "\"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1678
1679                                 return [ 'uploaded-animate-svg', $strippedElement, $attrib, $value ];
1680                         }
1681
1682                         # use set/animate to add event-handler attribute to parent
1683                         if ( ( $strippedElement == 'set' || $strippedElement == 'animate' )
1684                                 && $stripped == 'attributename'
1685                                 && substr( $value, 0, 2 ) == 'on'
1686                         ) {
1687                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with "
1688                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1689
1690                                 return [ 'uploaded-setting-event-handler-svg', $strippedElement, $stripped, $value ];
1691                         }
1692
1693                         # use set to add href attribute to parent element
1694                         if ( $strippedElement == 'set'
1695                                 && $stripped == 'attributename'
1696                                 && strpos( $value, 'href' ) !== false
1697                         ) {
1698                                 wfDebug( __METHOD__ . ": Found svg setting href attribute '$value' in uploaded file.\n" );
1699
1700                                 return [ 'uploaded-setting-href-svg' ];
1701                         }
1702
1703                         # use set to add a remote / data / script target to an element
1704                         if ( $strippedElement == 'set'
1705                                 && $stripped == 'to'
1706                                 && preg_match( '!(http|https|data|script):!sim', $value )
1707                         ) {
1708                                 wfDebug( __METHOD__ . ": Found svg setting attribute to '$value' in uploaded file.\n" );
1709
1710                                 return [ 'uploaded-wrong-setting-svg', $value ];
1711                         }
1712
1713                         # use handler attribute with remote / data / script
1714                         if ( $stripped == 'handler' && preg_match( '!(http|https|data|script):!sim', $value ) ) {
1715                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script "
1716                                         . "'$attrib'='$value' in uploaded file.\n" );
1717
1718                                 return [ 'uploaded-setting-handler-svg', $attrib, $value ];
1719                         }
1720
1721                         # use CSS styles to bring in remote code
1722                         if ( $stripped == 'style'
1723                                 && self::checkCssFragment( Sanitizer::normalizeCss( $value ) )
1724                         ) {
1725                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1726                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1727                                 return [ 'uploaded-remote-url-svg', $attrib, $value ];
1728                         }
1729
1730                         # Several attributes can include css, css character escaping isn't allowed
1731                         $cssAttrs = [ 'font', 'clip-path', 'fill', 'filter', 'marker',
1732                                 'marker-end', 'marker-mid', 'marker-start', 'mask', 'stroke' ];
1733                         if ( in_array( $stripped, $cssAttrs )
1734                                 && self::checkCssFragment( $value )
1735                         ) {
1736                                 wfDebug( __METHOD__ . ": Found svg setting a style with "
1737                                         . "remote url '$attrib'='$value' in uploaded file.\n" );
1738                                 return [ 'uploaded-remote-url-svg', $attrib, $value ];
1739                         }
1740
1741                         # image filters can pull in url, which could be svg that executes scripts
1742                         # Only allow url( "#foo" ). Do not allow url( http://example.com )
1743                         if ( $strippedElement == 'image'
1744                                 && $stripped == 'filter'
1745                                 && preg_match( '!url\s*\(\s*["\']?[^#]!sim', $value )
1746                         ) {
1747                                 wfDebug( __METHOD__ . ": Found image filter with url: "
1748                                         . "\"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1749
1750                                 return [ 'uploaded-image-filter-svg', $strippedElement, $stripped, $value ];
1751                         }
1752                 }
1753
1754                 return false; // No scripts detected
1755         }
1756
1757         /**
1758          * Check a block of CSS or CSS fragment for anything that looks like
1759          * it is bringing in remote code.
1760          * @param string $value a string of CSS
1761          * @param bool $propOnly only check css properties (start regex with :)
1762          * @return bool true if the CSS contains an illegal string, false if otherwise
1763          */
1764         private static function checkCssFragment( $value ) {
1765                 # Forbid external stylesheets, for both reliability and to protect viewer's privacy
1766                 if ( stripos( $value, '@import' ) !== false ) {
1767                         return true;
1768                 }
1769
1770                 # We allow @font-face to embed fonts with data: urls, so we snip the string
1771                 # 'url' out so this case won't match when we check for urls below
1772                 $pattern = '!(@font-face\s*{[^}]*src:)url(\("data:;base64,)!im';
1773                 $value = preg_replace( $pattern, '$1$2', $value );
1774
1775                 # Check for remote and executable CSS. Unlike in Sanitizer::checkCss, the CSS
1776                 # properties filter and accelerator don't seem to be useful for xss in SVG files.
1777                 # Expression and -o-link don't seem to work either, but filtering them here in case.
1778                 # Additionally, we catch remote urls like url("http:..., url('http:..., url(http:...,
1779                 # but not local ones such as url("#..., url('#..., url(#....
1780                 if ( preg_match( '!expression
1781                                 | -o-link\s*:
1782                                 | -o-link-source\s*:
1783                                 | -o-replace\s*:!imx', $value ) ) {
1784                         return true;
1785                 }
1786
1787                 if ( preg_match_all(
1788                                 "!(\s*(url|image|image-set)\s*\(\s*[\"']?\s*[^#]+.*?\))!sim",
1789                                 $value,
1790                                 $matches
1791                         ) !== 0
1792                 ) {
1793                         # TODO: redo this in one regex. Until then, url("#whatever") matches the first
1794                         foreach ( $matches[1] as $match ) {
1795                                 if ( !preg_match( "!\s*(url|image|image-set)\s*\(\s*(#|'#|\"#)!im", $match ) ) {
1796                                         return true;
1797                                 }
1798                         }
1799                 }
1800
1801                 if ( preg_match( '/[\000-\010\013\016-\037\177]/', $value ) ) {
1802                         return true;
1803                 }
1804
1805                 return false;
1806         }
1807
1808         /**
1809          * Divide the element name passed by the xml parser to the callback into URI and prifix.
1810          * @param string $element
1811          * @return array Containing the namespace URI and prefix
1812          */
1813         private static function splitXmlNamespace( $element ) {
1814                 // 'http://www.w3.org/2000/svg:script' -> [ 'http://www.w3.org/2000/svg', 'script' ]
1815                 $parts = explode( ':', strtolower( $element ) );
1816                 $name = array_pop( $parts );
1817                 $ns = implode( ':', $parts );
1818
1819                 return [ $ns, $name ];
1820         }
1821
1822         /**
1823          * @param string $name
1824          * @return string
1825          */
1826         private function stripXmlNamespace( $name ) {
1827                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1828                 $parts = explode( ':', strtolower( $name ) );
1829
1830                 return array_pop( $parts );
1831         }
1832
1833         /**
1834          * Generic wrapper function for a virus scanner program.
1835          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1836          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1837          *
1838          * @param string $file Pathname to the temporary upload file
1839          * @return bool|null|string False if not virus is found, null if the scan fails or is disabled,
1840          *   or a string containing feedback from the virus scanner if a virus was found.
1841          *   If textual feedback is missing but a virus was found, this function returns true.
1842          */
1843         public static function detectVirus( $file ) {
1844                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1845
1846                 if ( !$wgAntivirus ) {
1847                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1848
1849                         return null;
1850                 }
1851
1852                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1853                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1854                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1855                                 [ 'virus-badscanner', $wgAntivirus ] );
1856
1857                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1858                 }
1859
1860                 # look up scanner configuration
1861                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1862                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1863                 $msgPattern = $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ?? null;
1864
1865                 if ( strpos( $command, "%f" ) === false ) {
1866                         # simple pattern: append file to scan
1867                         $command .= " " . Shell::escape( $file );
1868                 } else {
1869                         # complex pattern: replace "%f" with file to scan
1870                         $command = str_replace( "%f", Shell::escape( $file ), $command );
1871                 }
1872
1873                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1874
1875                 # execute virus scanner
1876                 $exitCode = false;
1877
1878                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1879                 #      that does not seem to be worth the pain.
1880                 #      Ask me (Duesentrieb) about it if it's ever needed.
1881                 $output = wfShellExecWithStderr( $command, $exitCode );
1882
1883                 # map exit code to AV_xxx constants.
1884                 $mappedCode = $exitCode;
1885                 if ( $exitCodeMap ) {
1886                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1887                                 $mappedCode = $exitCodeMap[$exitCode];
1888                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1889                                 $mappedCode = $exitCodeMap["*"];
1890                         }
1891                 }
1892
1893                 /* NB: AV_NO_VIRUS is 0 but AV_SCAN_FAILED is false,
1894                  * so we need the strict equalities === and thus can't use a switch here
1895                  */
1896                 if ( $mappedCode === AV_SCAN_FAILED ) {
1897                         # scan failed (code was mapped to false by $exitCodeMap)
1898                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1899
1900                         $output = $wgAntivirusRequired
1901                                 ? wfMessage( 'virus-scanfailed', [ $exitCode ] )->text()
1902                                 : null;
1903                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1904                         # scan failed because filetype is unknown (probably imune)
1905                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1906                         $output = null;
1907                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1908                         # no virus found
1909                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1910                         $output = false;
1911                 } else {
1912                         $output = trim( $output );
1913
1914                         if ( !$output ) {
1915                                 $output = true; # if there's no output, return true
1916                         } elseif ( $msgPattern ) {
1917                                 $groups = [];
1918                                 if ( preg_match( $msgPattern, $output, $groups ) && $groups[1] ) {
1919                                         $output = $groups[1];
1920                                 }
1921                         }
1922
1923                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1924                 }
1925
1926                 return $output;
1927         }
1928
1929         /**
1930          * Check if there's an overwrite conflict and, if so, if restrictions
1931          * forbid this user from performing the upload.
1932          *
1933          * @param User $user
1934          *
1935          * @return bool|array
1936          */
1937         private function checkOverwrite( $user ) {
1938                 // First check whether the local file can be overwritten
1939                 $file = $this->getLocalFile();
1940                 $file->load( File::READ_LATEST );
1941                 if ( $file->exists() ) {
1942                         if ( !self::userCanReUpload( $user, $file ) ) {
1943                                 return [ 'fileexists-forbidden', $file->getName() ];
1944                         } else {
1945                                 return true;
1946                         }
1947                 }
1948
1949                 /* Check shared conflicts: if the local file does not exist, but
1950                  * wfFindFile finds a file, it exists in a shared repository.
1951                  */
1952                 $file = wfFindFile( $this->getTitle(), [ 'latest' => true ] );
1953                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1954                         return [ 'fileexists-shared-forbidden', $file->getName() ];
1955                 }
1956
1957                 return true;
1958         }
1959
1960         /**
1961          * Check if a user is the last uploader
1962          *
1963          * @param User $user
1964          * @param File $img
1965          * @return bool
1966          */
1967         public static function userCanReUpload( User $user, File $img ) {
1968                 if ( $user->isAllowed( 'reupload' ) ) {
1969                         return true; // non-conditional
1970                 } elseif ( !$user->isAllowed( 'reupload-own' ) ) {
1971                         return false;
1972                 }
1973
1974                 if ( !( $img instanceof LocalFile ) ) {
1975                         return false;
1976                 }
1977
1978                 $img->load();
1979
1980                 return $user->getId() == $img->getUser( 'id' );
1981         }
1982
1983         /**
1984          * Helper function that does various existence checks for a file.
1985          * The following checks are performed:
1986          * - The file exists
1987          * - Article with the same name as the file exists
1988          * - File exists with normalized extension
1989          * - The file looks like a thumbnail and the original exists
1990          *
1991          * @param File $file The File object to check
1992          * @return mixed False if the file does not exists, else an array
1993          */
1994         public static function getExistsWarning( $file ) {
1995                 if ( $file->exists() ) {
1996                         return [ 'warning' => 'exists', 'file' => $file ];
1997                 }
1998
1999                 if ( $file->getTitle()->getArticleID() ) {
2000                         return [ 'warning' => 'page-exists', 'file' => $file ];
2001                 }
2002
2003                 if ( strpos( $file->getName(), '.' ) == false ) {
2004                         $partname = $file->getName();
2005                         $extension = '';
2006                 } else {
2007                         $n = strrpos( $file->getName(), '.' );
2008                         $extension = substr( $file->getName(), $n + 1 );
2009                         $partname = substr( $file->getName(), 0, $n );
2010                 }
2011                 $normalizedExtension = File::normalizeExtension( $extension );
2012
2013                 if ( $normalizedExtension != $extension ) {
2014                         // We're not using the normalized form of the extension.
2015                         // Normal form is lowercase, using most common of alternate
2016                         // extensions (eg 'jpg' rather than 'JPEG').
2017
2018                         // Check for another file using the normalized form...
2019                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
2020                         $file_lc = wfLocalFile( $nt_lc );
2021
2022                         if ( $file_lc->exists() ) {
2023                                 return [
2024                                         'warning' => 'exists-normalized',
2025                                         'file' => $file,
2026                                         'normalizedFile' => $file_lc
2027                                 ];
2028                         }
2029                 }
2030
2031                 // Check for files with the same name but a different extension
2032                 $similarFiles = RepoGroup::singleton()->getLocalRepo()->findFilesByPrefix(
2033                         "{$partname}.", 1 );
2034                 if ( count( $similarFiles ) ) {
2035                         return [
2036                                 'warning' => 'exists-normalized',
2037                                 'file' => $file,
2038                                 'normalizedFile' => $similarFiles[0],
2039                         ];
2040                 }
2041
2042                 if ( self::isThumbName( $file->getName() ) ) {
2043                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
2044                         $nt_thb = Title::newFromText(
2045                                 substr( $partname, strpos( $partname, '-' ) + 1 ) . '.' . $extension,
2046                                 NS_FILE
2047                         );
2048                         $file_thb = wfLocalFile( $nt_thb );
2049                         if ( $file_thb->exists() ) {
2050                                 return [
2051                                         'warning' => 'thumb',
2052                                         'file' => $file,
2053                                         'thumbFile' => $file_thb
2054                                 ];
2055                         } else {
2056                                 // File does not exist, but we just don't like the name
2057                                 return [
2058                                         'warning' => 'thumb-name',
2059                                         'file' => $file,
2060                                         'thumbFile' => $file_thb
2061                                 ];
2062                         }
2063                 }
2064
2065                 foreach ( self::getFilenamePrefixBlacklist() as $prefix ) {
2066                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
2067                                 return [
2068                                         'warning' => 'bad-prefix',
2069                                         'file' => $file,
2070                                         'prefix' => $prefix
2071                                 ];
2072                         }
2073                 }
2074
2075                 return false;
2076         }
2077
2078         /**
2079          * Helper function that checks whether the filename looks like a thumbnail
2080          * @param string $filename
2081          * @return bool
2082          */
2083         public static function isThumbName( $filename ) {
2084                 $n = strrpos( $filename, '.' );
2085                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
2086
2087                 return (
2088                         substr( $partname, 3, 3 ) == 'px-' ||
2089                         substr( $partname, 2, 3 ) == 'px-'
2090                 ) &&
2091                 preg_match( "/[0-9]{2}/", substr( $partname, 0, 2 ) );
2092         }
2093
2094         /**
2095          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
2096          *
2097          * @return array List of prefixes
2098          */
2099         public static function getFilenamePrefixBlacklist() {
2100                 $blacklist = [];
2101                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
2102                 if ( !$message->isDisabled() ) {
2103                         $lines = explode( "\n", $message->plain() );
2104                         foreach ( $lines as $line ) {
2105                                 // Remove comment lines
2106                                 $comment = substr( trim( $line ), 0, 1 );
2107                                 if ( $comment == '#' || $comment == '' ) {
2108                                         continue;
2109                                 }
2110                                 // Remove additional comments after a prefix
2111                                 $comment = strpos( $line, '#' );
2112                                 if ( $comment > 0 ) {
2113                                         $line = substr( $line, 0, $comment - 1 );
2114                                 }
2115                                 $blacklist[] = trim( $line );
2116                         }
2117                 }
2118
2119                 return $blacklist;
2120         }
2121
2122         /**
2123          * Gets image info about the file just uploaded.
2124          *
2125          * Also has the effect of setting metadata to be an 'indexed tag name' in
2126          * returned API result if 'metadata' was requested. Oddly, we have to pass
2127          * the "result" object down just so it can do that with the appropriate
2128          * format, presumably.
2129          *
2130          * @param ApiResult $result
2131          * @return array Image info
2132          */
2133         public function getImageInfo( $result ) {
2134                 $localFile = $this->getLocalFile();
2135                 $stashFile = $this->getStashFile();
2136                 // Calling a different API module depending on whether the file was stashed is less than optimal.
2137                 // In fact, calling API modules here at all is less than optimal. Maybe it should be refactored.
2138                 if ( $stashFile ) {
2139                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
2140                         $info = ApiQueryStashImageInfo::getInfo( $stashFile, array_flip( $imParam ), $result );
2141                 } else {
2142                         $imParam = ApiQueryImageInfo::getPropertyNames();
2143                         $info = ApiQueryImageInfo::getInfo( $localFile, array_flip( $imParam ), $result );
2144                 }
2145
2146                 return $info;
2147         }
2148
2149         /**
2150          * @param array $error
2151          * @return Status
2152          */
2153         public function convertVerifyErrorToStatus( $error ) {
2154                 $code = $error['status'];
2155                 unset( $code['status'] );
2156
2157                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
2158         }
2159
2160         /**
2161          * Get the MediaWiki maximum uploaded file size for given type of upload, based on
2162          * $wgMaxUploadSize.
2163          *
2164          * @param null|string $forType
2165          * @return int
2166          */
2167         public static function getMaxUploadSize( $forType = null ) {
2168                 global $wgMaxUploadSize;
2169
2170                 if ( is_array( $wgMaxUploadSize ) ) {
2171                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
2172                                 return $wgMaxUploadSize[$forType];
2173                         } else {
2174                                 return $wgMaxUploadSize['*'];
2175                         }
2176                 } else {
2177                         return intval( $wgMaxUploadSize );
2178                 }
2179         }
2180
2181         /**
2182          * Get the PHP maximum uploaded file size, based on ini settings. If there is no limit or the
2183          * limit can't be guessed, returns a very large number (PHP_INT_MAX).
2184          *
2185          * @since 1.27
2186          * @return int
2187          */
2188         public static function getMaxPhpUploadSize() {
2189                 $phpMaxFileSize = wfShorthandToInteger(
2190                         ini_get( 'upload_max_filesize' ) ?: ini_get( 'hhvm.server.upload.upload_max_file_size' ),
2191                         PHP_INT_MAX
2192                 );
2193                 $phpMaxPostSize = wfShorthandToInteger(
2194                         ini_get( 'post_max_size' ) ?: ini_get( 'hhvm.server.max_post_size' ),
2195                         PHP_INT_MAX
2196                 ) ?: PHP_INT_MAX;
2197                 return min( $phpMaxFileSize, $phpMaxPostSize );
2198         }
2199
2200         /**
2201          * Get the current status of a chunked upload (used for polling)
2202          *
2203          * The value will be read from cache.
2204          *
2205          * @param User $user
2206          * @param string $statusKey
2207          * @return Status[]|bool
2208          */
2209         public static function getSessionStatus( User $user, $statusKey ) {
2210                 $cache = MediaWikiServices::getInstance()->getMainObjectStash();
2211                 $key = $cache->makeKey( 'uploadstatus', $user->getId() ?: md5( $user->getName() ), $statusKey );
2212
2213                 return $cache->get( $key );
2214         }
2215
2216         /**
2217          * Set the current status of a chunked upload (used for polling)
2218          *
2219          * The value will be set in cache for 1 day
2220          *
2221          * @param User $user
2222          * @param string $statusKey
2223          * @param array|bool $value
2224          * @return void
2225          */
2226         public static function setSessionStatus( User $user, $statusKey, $value ) {
2227                 $cache = MediaWikiServices::getInstance()->getMainObjectStash();
2228                 $key = $cache->makeKey( 'uploadstatus', $user->getId() ?: md5( $user->getName() ), $statusKey );
2229
2230                 if ( $value === false ) {
2231                         $cache->delete( $key );
2232                 } else {
2233                         $cache->set( $key, $value, $cache::TTL_DAY );
2234                 }
2235         }
2236 }