includes/upload/UploadBase.php

   1 <?php
   2 /**
   3  * Base class for the backend of file upload.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Upload
  22  */
  23
  24 /**
  25  * @defgroup Upload Upload related
  26  */
  27
  28 /**
  29  * @ingroup Upload
  30  *
  31  * UploadBase and subclasses are the backend of MediaWiki's file uploads.
  32  * The frontends are formed by ApiUpload and SpecialUpload.
  33  *
  34  * See also includes/docs/upload.txt
  35  *
  36  * @author Brion Vibber
  37  * @author Bryan Tong Minh
  38  * @author Michael Dale
  39  */
  40 abstract class UploadBase {
  41         protected $mTempPath;
  42         protected $mDesiredDestName, $mDestName, $mRemoveTempFile, $mSourceType;
  43         protected $mTitle = false, $mTitleError = 0;
  44         protected $mFilteredName, $mFinalExtension;
  45         protected $mLocalFile, $mFileSize, $mFileProps;
  46         protected $mBlackListedExtensions;
  47         protected $mJavaDetected;
  48
  49         protected static $safeXmlEncodings = array( 'UTF-8', 'ISO-8859-1', 'ISO-8859-2', 'UTF-16', 'UTF-32' );
  50
  51         const SUCCESS = 0;
  52         const OK = 0;
  53         const EMPTY_FILE = 3;
  54         const MIN_LENGTH_PARTNAME = 4;
  55         const ILLEGAL_FILENAME = 5;
  56         const OVERWRITE_EXISTING_FILE = 7; # Not used anymore; handled by verifyTitlePermissions()
  57         const FILETYPE_MISSING = 8;
  58         const FILETYPE_BADTYPE = 9;
  59         const VERIFICATION_ERROR = 10;
  60
  61         # HOOK_ABORTED is the new name of UPLOAD_VERIFICATION_ERROR
  62         const UPLOAD_VERIFICATION_ERROR = 11;
  63         const HOOK_ABORTED = 11;
  64         const FILE_TOO_LARGE = 12;
  65         const WINDOWS_NONASCII_FILENAME = 13;
  66         const FILENAME_TOO_LONG = 14;
  67
  68         const SESSION_STATUS_KEY = 'wsUploadStatusData';
  69
  70         /**
  71          * @param $error int
  72          * @return string
  73          */
  74         public function getVerificationErrorCode( $error ) {
  75                 $code_to_status = array(
  76                         self::EMPTY_FILE => 'empty-file',
  77                         self::FILE_TOO_LARGE => 'file-too-large',
  78                         self::FILETYPE_MISSING => 'filetype-missing',
  79                         self::FILETYPE_BADTYPE => 'filetype-banned',
  80                         self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
  81                         self::ILLEGAL_FILENAME => 'illegal-filename',
  82                         self::OVERWRITE_EXISTING_FILE => 'overwrite',
  83                         self::VERIFICATION_ERROR => 'verification-error',
  84                         self::HOOK_ABORTED => 'hookaborted',
  85                         self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
  86                         self::FILENAME_TOO_LONG => 'filename-toolong',
  87                 );
  88                 if ( isset( $code_to_status[$error] ) ) {
  89                         return $code_to_status[$error];
  90                 }
  91
  92                 return 'unknown-error';
  93         }
  94
  95         /**
  96          * Returns true if uploads are enabled.
  97          * Can be override by subclasses.
  98          * @return bool
  99          */
 100         public static function isEnabled() {
 101                 global $wgEnableUploads;
 102
 103                 if ( !$wgEnableUploads ) {
 104                         return false;
 105                 }
 106
 107                 # Check php's file_uploads setting
 108                 return wfIsHipHop() || wfIniGetBool( 'file_uploads' );
 109         }
 110
 111         /**
 112          * Returns true if the user can use this upload module or else a string
 113          * identifying the missing permission.
 114          * Can be overridden by subclasses.
 115          *
 116          * @param $user User
 117          * @return bool
 118          */
 119         public static function isAllowed( $user ) {
 120                 foreach ( array( 'upload', 'edit' ) as $permission ) {
 121                         if ( !$user->isAllowed( $permission ) ) {
 122                                 return $permission;
 123                         }
 124                 }
 125                 return true;
 126         }
 127
 128         // Upload handlers. Should probably just be a global.
 129         static $uploadHandlers = array( 'Stash', 'File', 'Url' );
 130
 131         /**
 132          * Create a form of UploadBase depending on wpSourceType and initializes it
 133          *
 134          * @param $request WebRequest
 135          * @param $type
 136          * @return null
 137          */
 138         public static function createFromRequest( &$request, $type = null ) {
 139                 $type = $type ? $type : $request->getVal( 'wpSourceType', 'File' );
 140
 141                 if ( !$type ) {
 142                         return null;
 143                 }
 144
 145                 // Get the upload class
 146                 $type = ucfirst( $type );
 147
 148                 // Give hooks the chance to handle this request
 149                 $className = null;
 150                 wfRunHooks( 'UploadCreateFromRequest', array( $type, &$className ) );
 151                 if ( is_null( $className ) ) {
 152                         $className = 'UploadFrom' . $type;
 153                         wfDebug( __METHOD__ . ": class name: $className\n" );
 154                         if ( !in_array( $type, self::$uploadHandlers ) ) {
 155                                 return null;
 156                         }
 157                 }
 158
 159                 // Check whether this upload class is enabled
 160                 if ( !call_user_func( array( $className, 'isEnabled' ) ) ) {
 161                         return null;
 162                 }
 163
 164                 // Check whether the request is valid
 165                 if ( !call_user_func( array( $className, 'isValidRequest' ), $request ) ) {
 166                         return null;
 167                 }
 168
 169                 $handler = new $className;
 170
 171                 $handler->initializeFromRequest( $request );
 172                 return $handler;
 173         }
 174
 175         /**
 176          * Check whether a request if valid for this handler
 177          * @param $request
 178          * @return bool
 179          */
 180         public static function isValidRequest( $request ) {
 181                 return false;
 182         }
 183
 184         public function __construct() {}
 185
 186         /**
 187          * Returns the upload type. Should be overridden by child classes
 188          *
 189          * @since 1.18
 190          * @return string
 191          */
 192         public function getSourceType() {
 193                 return null;
 194         }
 195
 196         /**
 197          * Initialize the path information
 198          * @param string $name the desired destination name
 199          * @param string $tempPath the temporary path
 200          * @param int $fileSize the file size
 201          * @param bool $removeTempFile (false) remove the temporary file?
 202          * @throws MWException
 203          */
 204         public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
 205                 $this->mDesiredDestName = $name;
 206                 if ( FileBackend::isStoragePath( $tempPath ) ) {
 207                         throw new MWException( __METHOD__ . " given storage path `$tempPath`." );
 208                 }
 209                 $this->mTempPath = $tempPath;
 210                 $this->mFileSize = $fileSize;
 211                 $this->mRemoveTempFile = $removeTempFile;
 212         }
 213
 214         /**
 215          * Initialize from a WebRequest. Override this in a subclass.
 216          */
 217         abstract public function initializeFromRequest( &$request );
 218
 219         /**
 220          * Fetch the file. Usually a no-op
 221          * @return Status
 222          */
 223         public function fetchFile() {
 224                 return Status::newGood();
 225         }
 226
 227         /**
 228          * Return true if the file is empty
 229          * @return bool
 230          */
 231         public function isEmptyFile() {
 232                 return empty( $this->mFileSize );
 233         }
 234
 235         /**
 236          * Return the file size
 237          * @return integer
 238          */
 239         public function getFileSize() {
 240                 return $this->mFileSize;
 241         }
 242
 243         /**
 244          * Get the base 36 SHA1 of the file
 245          * @return string
 246          */
 247         public function getTempFileSha1Base36() {
 248                 return FSFile::getSha1Base36FromPath( $this->mTempPath );
 249         }
 250
 251         /**
 252          * @param string $srcPath the source path
 253          * @return string the real path if it was a virtual URL
 254          */
 255         function getRealPath( $srcPath ) {
 256                 wfProfileIn( __METHOD__ );
 257                 $repo = RepoGroup::singleton()->getLocalRepo();
 258                 if ( $repo->isVirtualUrl( $srcPath ) ) {
 259                         // @todo just make uploads work with storage paths
 260                         // UploadFromStash loads files via virtual URLs
 261                         $tmpFile = $repo->getLocalCopy( $srcPath );
 262                         $tmpFile->bind( $this ); // keep alive with $this
 263                         wfProfileOut( __METHOD__ );
 264                         return $tmpFile->getPath();
 265                 }
 266                 wfProfileOut( __METHOD__ );
 267                 return $srcPath;
 268         }
 269
 270         /**
 271          * Verify whether the upload is sane.
 272          * @return mixed self::OK or else an array with error information
 273          */
 274         public function verifyUpload() {
 275                 wfProfileIn( __METHOD__ );
 276
 277                 /**
 278                  * If there was no filename or a zero size given, give up quick.
 279                  */
 280                 if ( $this->isEmptyFile() ) {
 281                         wfProfileOut( __METHOD__ );
 282                         return array( 'status' => self::EMPTY_FILE );
 283                 }
 284
 285                 /**
 286                  * Honor $wgMaxUploadSize
 287                  */
 288                 $maxSize = self::getMaxUploadSize( $this->getSourceType() );
 289                 if ( $this->mFileSize > $maxSize ) {
 290                         wfProfileOut( __METHOD__ );
 291                         return array(
 292                                 'status' => self::FILE_TOO_LARGE,
 293                                 'max' => $maxSize,
 294                         );
 295                 }
 296
 297                 /**
 298                  * Look at the contents of the file; if we can recognize the
 299                  * type but it's corrupt or data of the wrong type, we should
 300                  * probably not accept it.
 301                  */
 302                 $verification = $this->verifyFile();
 303                 if ( $verification !== true ) {
 304                         wfProfileOut( __METHOD__ );
 305                         return array(
 306                                 'status' => self::VERIFICATION_ERROR,
 307                                 'details' => $verification
 308                         );
 309                 }
 310
 311                 /**
 312                  * Make sure this file can be created
 313                  */
 314                 $result = $this->validateName();
 315                 if ( $result !== true ) {
 316                         wfProfileOut( __METHOD__ );
 317                         return $result;
 318                 }
 319
 320                 $error = '';
 321                 if ( !wfRunHooks( 'UploadVerification',
 322                         array( $this->mDestName, $this->mTempPath, &$error ) ) )
 323                 {
 324                         wfProfileOut( __METHOD__ );
 325                         return array( 'status' => self::HOOK_ABORTED, 'error' => $error );
 326                 }
 327
 328                 wfProfileOut( __METHOD__ );
 329                 return array( 'status' => self::OK );
 330         }
 331
 332         /**
 333          * Verify that the name is valid and, if necessary, that we can overwrite
 334          *
 335          * @return mixed true if valid, otherwise and array with 'status'
 336          * and other keys
 337          **/
 338         public function validateName() {
 339                 $nt = $this->getTitle();
 340                 if ( is_null( $nt ) ) {
 341                         $result = array( 'status' => $this->mTitleError );
 342                         if ( $this->mTitleError == self::ILLEGAL_FILENAME ) {
 343                                 $result['filtered'] = $this->mFilteredName;
 344                         }
 345                         if ( $this->mTitleError == self::FILETYPE_BADTYPE ) {
 346                                 $result['finalExt'] = $this->mFinalExtension;
 347                                 if ( count( $this->mBlackListedExtensions ) ) {
 348                                         $result['blacklistedExt'] = $this->mBlackListedExtensions;
 349                                 }
 350                         }
 351                         return $result;
 352                 }
 353                 $this->mDestName = $this->getLocalFile()->getName();
 354
 355                 return true;
 356         }
 357
 358         /**
 359          * Verify the mime type.
 360          *
 361          * @note Only checks that it is not an evil mime. The does it have
 362          *  correct extension given its mime type check is in verifyFile.
 363          * @param string $mime representing the mime
 364          * @return mixed true if the file is verified, an array otherwise
 365          */
 366         protected function verifyMimeType( $mime ) {
 367                 global $wgVerifyMimeType;
 368                 wfProfileIn( __METHOD__ );
 369                 if ( $wgVerifyMimeType ) {
 370                         wfDebug( "\n\nmime: <$mime> extension: <{$this->mFinalExtension}>\n\n" );
 371                         global $wgMimeTypeBlacklist;
 372                         if ( $this->checkFileExtension( $mime, $wgMimeTypeBlacklist ) ) {
 373                                 wfProfileOut( __METHOD__ );
 374                                 return array( 'filetype-badmime', $mime );
 375                         }
 376
 377                         # Check IE type
 378                         $fp = fopen( $this->mTempPath, 'rb' );
 379                         $chunk = fread( $fp, 256 );
 380                         fclose( $fp );
 381
 382                         $magic = MimeMagic::singleton();
 383                         $extMime = $magic->guessTypesForExtension( $this->mFinalExtension );
 384                         $ieTypes = $magic->getIEMimeTypes( $this->mTempPath, $chunk, $extMime );
 385                         foreach ( $ieTypes as $ieType ) {
 386                                 if ( $this->checkFileExtension( $ieType, $wgMimeTypeBlacklist ) ) {
 387                                         wfProfileOut( __METHOD__ );
 388                                         return array( 'filetype-bad-ie-mime', $ieType );
 389                                 }
 390                         }
 391                 }
 392
 393                 wfProfileOut( __METHOD__ );
 394                 return true;
 395         }
 396
 397
 398         /**
 399          * Verifies that it's ok to include the uploaded file
 400          *
 401          * @return mixed true of the file is verified, array otherwise.
 402          */
 403         protected function verifyFile() {
 404                 global $wgVerifyMimeType;
 405                 wfProfileIn( __METHOD__ );
 406
 407                 $status = $this->verifyPartialFile();
 408                 if ( $status !== true ) {
 409                         wfProfileOut( __METHOD__ );
 410                         return $status;
 411                 }
 412
 413                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 414                 $mime = $this->mFileProps['file-mime'];
 415
 416                 if ( $wgVerifyMimeType ) {
 417                         # XXX: Missing extension will be caught by validateName() via getTitle()
 418                         if ( $this->mFinalExtension != '' && !$this->verifyExtension( $mime, $this->mFinalExtension ) ) {
 419                                 wfProfileOut( __METHOD__ );
 420                                 return array( 'filetype-mime-mismatch', $this->mFinalExtension, $mime );
 421                         }
 422                 }
 423
 424
 425                 $handler = MediaHandler::getHandler( $mime );
 426                 if ( $handler ) {
 427                         $handlerStatus = $handler->verifyUpload( $this->mTempPath );
 428                         if ( !$handlerStatus->isOK() ) {
 429                                 $errors = $handlerStatus->getErrorsArray();
 430                                 wfProfileOut( __METHOD__ );
 431                                 return reset( $errors );
 432                         }
 433                 }
 434
 435                 wfRunHooks( 'UploadVerifyFile', array( $this, $mime, &$status ) );
 436                 if ( $status !== true ) {
 437                         wfProfileOut( __METHOD__ );
 438                         return $status;
 439                 }
 440
 441                 wfDebug( __METHOD__ . ": all clear; passing.\n" );
 442                 wfProfileOut( __METHOD__ );
 443                 return true;
 444         }
 445
 446         /**
 447          * A verification routine suitable for partial files
 448          *
 449          * Runs the blacklist checks, but not any checks that may
 450          * assume the entire file is present.
 451          *
 452          * @return Mixed true for valid or array with error message key.
 453          */
 454         protected function verifyPartialFile() {
 455                 global $wgAllowJavaUploads, $wgDisableUploadScriptChecks;
 456                 wfProfileIn( __METHOD__ );
 457
 458                 # getTitle() sets some internal parameters like $this->mFinalExtension
 459                 $this->getTitle();
 460
 461                 $this->mFileProps = FSFile::getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
 462
 463                 # check mime type, if desired
 464                 $mime = $this->mFileProps['file-mime'];
 465                 $status = $this->verifyMimeType( $mime );
 466                 if ( $status !== true ) {
 467                         wfProfileOut( __METHOD__ );
 468                         return $status;
 469                 }
 470
 471                 # check for htmlish code and javascript
 472                 if ( !$wgDisableUploadScriptChecks ) {
 473                         if ( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
 474                                 wfProfileOut( __METHOD__ );
 475                                 return array( 'uploadscripted' );
 476                         }
 477                         if ( $this->mFinalExtension == 'svg' || $mime == 'image/svg+xml' ) {
 478                                 if ( $this->detectScriptInSvg( $this->mTempPath ) ) {
 479                                         wfProfileOut( __METHOD__ );
 480                                         return array( 'uploadscripted' );
 481                                 }
 482                         }
 483                 }
 484
 485                 # Check for Java applets, which if uploaded can bypass cross-site
 486                 # restrictions.
 487                 if ( !$wgAllowJavaUploads ) {
 488                         $this->mJavaDetected = false;
 489                         $zipStatus = ZipDirectoryReader::read( $this->mTempPath,
 490                                 array( $this, 'zipEntryCallback' ) );
 491                         if ( !$zipStatus->isOK() ) {
 492                                 $errors = $zipStatus->getErrorsArray();
 493                                 $error = reset( $errors );
 494                                 if ( $error[0] !== 'zip-wrong-format' ) {
 495                                         wfProfileOut( __METHOD__ );
 496                                         return $error;
 497                                 }
 498                         }
 499                         if ( $this->mJavaDetected ) {
 500                                 wfProfileOut( __METHOD__ );
 501                                 return array( 'uploadjava' );
 502                         }
 503                 }
 504
 505                 # Scan the uploaded file for viruses
 506                 $virus = $this->detectVirus( $this->mTempPath );
 507                 if ( $virus ) {
 508                         wfProfileOut( __METHOD__ );
 509                         return array( 'uploadvirus', $virus );
 510                 }
 511
 512                 wfProfileOut( __METHOD__ );
 513                 return true;
 514         }
 515
 516         /**
 517          * Callback for ZipDirectoryReader to detect Java class files.
 518          */
 519         function zipEntryCallback( $entry ) {
 520                 $names = array( $entry['name'] );
 521
 522                 // If there is a null character, cut off the name at it, because JDK's
 523                 // ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
 524                 // were constructed which had ".class\0" followed by a string chosen to
 525                 // make the hash collide with the truncated name, that file could be
 526                 // returned in response to a request for the .class file.
 527                 $nullPos = strpos( $entry['name'], "\000" );
 528                 if ( $nullPos !== false ) {
 529                         $names[] = substr( $entry['name'], 0, $nullPos );
 530                 }
 531
 532                 // If there is a trailing slash in the file name, we have to strip it,
 533                 // because that's what ZIP_GetEntry() does.
 534                 if ( preg_grep( '!\.class/?$!', $names ) ) {
 535                         $this->mJavaDetected = true;
 536                 }
 537         }
 538
 539         /**
 540          * Alias for verifyTitlePermissions. The function was originally 'verifyPermissions'
 541          * but that suggests it's checking the user, when it's really checking the title + user combination.
 542          * @param $user User object to verify the permissions against
 543          * @return mixed An array as returned by getUserPermissionsErrors or true
 544          *               in case the user has proper permissions.
 545          */
 546         public function verifyPermissions( $user ) {
 547                 return $this->verifyTitlePermissions( $user );
 548         }
 549
 550         /**
 551          * Check whether the user can edit, upload and create the image. This
 552          * checks only against the current title; if it returns errors, it may
 553          * very well be that another title will not give errors. Therefore
 554          * isAllowed() should be called as well for generic is-user-blocked or
 555          * can-user-upload checking.
 556          *
 557          * @param $user User object to verify the permissions against
 558          * @return mixed An array as returned by getUserPermissionsErrors or true
 559          *               in case the user has proper permissions.
 560          */
 561         public function verifyTitlePermissions( $user ) {
 562                 /**
 563                  * If the image is protected, non-sysop users won't be able
 564                  * to modify it by uploading a new revision.
 565                  */
 566                 $nt = $this->getTitle();
 567                 if ( is_null( $nt ) ) {
 568                         return true;
 569                 }
 570                 $permErrors = $nt->getUserPermissionsErrors( 'edit', $user );
 571                 $permErrorsUpload = $nt->getUserPermissionsErrors( 'upload', $user );
 572                 if ( !$nt->exists() ) {
 573                         $permErrorsCreate = $nt->getUserPermissionsErrors( 'create', $user );
 574                 } else {
 575                         $permErrorsCreate = array();
 576                 }
 577                 if ( $permErrors || $permErrorsUpload || $permErrorsCreate ) {
 578                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsUpload, $permErrors ) );
 579                         $permErrors = array_merge( $permErrors, wfArrayDiff2( $permErrorsCreate, $permErrors ) );
 580                         return $permErrors;
 581                 }
 582
 583                 $overwriteError = $this->checkOverwrite( $user );
 584                 if ( $overwriteError !== true ) {
 585                         return array( $overwriteError );
 586                 }
 587
 588                 return true;
 589         }
 590
 591         /**
 592          * Check for non fatal problems with the file.
 593          *
 594          * This should not assume that mTempPath is set.
 595          *
 596          * @return Array of warnings
 597          */
 598         public function checkWarnings() {
 599                 global $wgLang;
 600                 wfProfileIn( __METHOD__ );
 601
 602                 $warnings = array();
 603
 604                 $localFile = $this->getLocalFile();
 605                 $filename = $localFile->getName();
 606
 607                 /**
 608                  * Check whether the resulting filename is different from the desired one,
 609                  * but ignore things like ucfirst() and spaces/underscore things
 610                  */
 611                 $comparableName = str_replace( ' ', '_', $this->mDesiredDestName );
 612                 $comparableName = Title::capitalize( $comparableName, NS_FILE );
 613
 614                 if ( $this->mDesiredDestName != $filename && $comparableName != $filename ) {
 615                         $warnings['badfilename'] = $filename;
 616                 }
 617
 618                 // Check whether the file extension is on the unwanted list
 619                 global $wgCheckFileExtensions, $wgFileExtensions;
 620                 if ( $wgCheckFileExtensions ) {
 621                         $extensions = array_unique( $wgFileExtensions );
 622                         if ( !$this->checkFileExtension( $this->mFinalExtension, $extensions ) ) {
 623                                 $warnings['filetype-unwanted-type'] = array( $this->mFinalExtension,
 624                                         $wgLang->commaList( $extensions ), count( $extensions ) );
 625                         }
 626                 }
 627
 628                 global $wgUploadSizeWarning;
 629                 if ( $wgUploadSizeWarning && ( $this->mFileSize > $wgUploadSizeWarning ) ) {
 630                         $warnings['large-file'] = array( $wgUploadSizeWarning, $this->mFileSize );
 631                 }
 632
 633                 if ( $this->mFileSize == 0 ) {
 634                         $warnings['emptyfile'] = true;
 635                 }
 636
 637                 $exists = self::getExistsWarning( $localFile );
 638                 if ( $exists !== false ) {
 639                         $warnings['exists'] = $exists;
 640                 }
 641
 642                 // Check dupes against existing files
 643                 $hash = $this->getTempFileSha1Base36();
 644                 $dupes = RepoGroup::singleton()->findBySha1( $hash );
 645                 $title = $this->getTitle();
 646                 // Remove all matches against self
 647                 foreach ( $dupes as $key => $dupe ) {
 648                         if ( $title->equals( $dupe->getTitle() ) ) {
 649                                 unset( $dupes[$key] );
 650                         }
 651                 }
 652                 if ( $dupes ) {
 653                         $warnings['duplicate'] = $dupes;
 654                 }
 655
 656                 // Check dupes against archives
 657                 $archivedImage = new ArchivedFile( null, 0, "{$hash}.{$this->mFinalExtension}" );
 658                 if ( $archivedImage->getID() > 0 ) {
 659                         $warnings['duplicate-archive'] = $archivedImage->getName();
 660                 }
 661
 662                 wfProfileOut( __METHOD__ );
 663                 return $warnings;
 664         }
 665
 666         /**
 667          * Really perform the upload. Stores the file in the local repo, watches
 668          * if necessary and runs the UploadComplete hook.
 669          *
 670          * @param $comment
 671          * @param $pageText
 672          * @param $watch
 673          * @param $user User
 674          *
 675          * @return Status indicating the whether the upload succeeded.
 676          */
 677         public function performUpload( $comment, $pageText, $watch, $user ) {
 678                 wfProfileIn( __METHOD__ );
 679
 680                 $status = $this->getLocalFile()->upload(
 681                         $this->mTempPath,
 682                         $comment,
 683                         $pageText,
 684                         File::DELETE_SOURCE,
 685                         $this->mFileProps,
 686                         false,
 687                         $user
 688                 );
 689
 690                 if ( $status->isGood() ) {
 691                         if ( $watch ) {
 692                                 WatchAction::doWatch( $this->getLocalFile()->getTitle(), $user, WatchedItem::IGNORE_USER_RIGHTS );
 693                         }
 694                         wfRunHooks( 'UploadComplete', array( &$this ) );
 695                 }
 696
 697                 wfProfileOut( __METHOD__ );
 698                 return $status;
 699         }
 700
 701         /**
 702          * Returns the title of the file to be uploaded. Sets mTitleError in case
 703          * the name was illegal.
 704          *
 705          * @return Title The title of the file or null in case the name was illegal
 706          */
 707         public function getTitle() {
 708                 if ( $this->mTitle !== false ) {
 709                         return $this->mTitle;
 710                 }
 711                 /* Assume that if a user specified File:Something.jpg, this is an error
 712                  * and that the namespace prefix needs to be stripped of.
 713                  */
 714                 $title = Title::newFromText( $this->mDesiredDestName );
 715                 if ( $title && $title->getNamespace() == NS_FILE ) {
 716                         $this->mFilteredName = $title->getDBkey();
 717                 } else {
 718                         $this->mFilteredName = $this->mDesiredDestName;
 719                 }
 720
 721                 # oi_archive_name is max 255 bytes, which include a timestamp and an
 722                 # exclamation mark, so restrict file name to 240 bytes.
 723                 if ( strlen( $this->mFilteredName ) > 240 ) {
 724                         $this->mTitleError = self::FILENAME_TOO_LONG;
 725                         return $this->mTitle = null;
 726                 }
 727
 728                 /**
 729                  * Chop off any directories in the given filename. Then
 730                  * filter out illegal characters, and try to make a legible name
 731                  * out of it. We'll strip some silently that Title would die on.
 732                  */
 733                 $this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
 734                 /* Normalize to title form before we do any further processing */
 735                 $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 736                 if ( is_null( $nt ) ) {
 737                         $this->mTitleError = self::ILLEGAL_FILENAME;
 738                         return $this->mTitle = null;
 739                 }
 740                 $this->mFilteredName = $nt->getDBkey();
 741
 742                 /**
 743                  * We'll want to blacklist against *any* 'extension', and use
 744                  * only the final one for the whitelist.
 745                  */
 746                 list( $partname, $ext ) = $this->splitExtensions( $this->mFilteredName );
 747
 748                 if ( count( $ext ) ) {
 749                         $this->mFinalExtension = trim( $ext[count( $ext ) - 1] );
 750                 } else {
 751                         $this->mFinalExtension = '';
 752
 753                         # No extension, try guessing one
 754                         $magic = MimeMagic::singleton();
 755                         $mime = $magic->guessMimeType( $this->mTempPath );
 756                         if ( $mime !== 'unknown/unknown' ) {
 757                                 # Get a space separated list of extensions
 758                                 $extList = $magic->getExtensionsForType( $mime );
 759                                 if ( $extList ) {
 760                                         # Set the extension to the canonical extension
 761                                         $this->mFinalExtension = strtok( $extList, ' ' );
 762
 763                                         # Fix up the other variables
 764                                         $this->mFilteredName .= ".{$this->mFinalExtension}";
 765                                         $nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
 766                                         $ext = array( $this->mFinalExtension );
 767                                 }
 768                         }
 769                 }
 770
 771                 /* Don't allow users to override the blacklist (check file extension) */
 772                 global $wgCheckFileExtensions, $wgStrictFileExtensions;
 773                 global $wgFileExtensions, $wgFileBlacklist;
 774
 775                 $blackListedExtensions = $this->checkFileExtensionList( $ext, $wgFileBlacklist );
 776
 777                 if ( $this->mFinalExtension == '' ) {
 778                         $this->mTitleError = self::FILETYPE_MISSING;
 779                         return $this->mTitle = null;
 780                 } elseif ( $blackListedExtensions ||
 781                                 ( $wgCheckFileExtensions && $wgStrictFileExtensions &&
 782                                         !$this->checkFileExtensionList( $ext, $wgFileExtensions ) ) ) {
 783                         $this->mBlackListedExtensions = $blackListedExtensions;
 784                         $this->mTitleError = self::FILETYPE_BADTYPE;
 785                         return $this->mTitle = null;
 786                 }
 787
 788                 // Windows may be broken with special characters, see bug XXX
 789                 if ( wfIsWindows() && !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() ) ) {
 790                         $this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
 791                         return $this->mTitle = null;
 792                 }
 793
 794                 # If there was more than one "extension", reassemble the base
 795                 # filename to prevent bogus complaints about length
 796                 if ( count( $ext ) > 1 ) {
 797                         for ( $i = 0; $i < count( $ext ) - 1; $i++ ) {
 798                                 $partname .= '.' . $ext[$i];
 799                         }
 800                 }
 801
 802                 if ( strlen( $partname ) < 1 ) {
 803                         $this->mTitleError = self::MIN_LENGTH_PARTNAME;
 804                         return $this->mTitle = null;
 805                 }
 806
 807                 return $this->mTitle = $nt;
 808         }
 809
 810         /**
 811          * Return the local file and initializes if necessary.
 812          *
 813          * @return LocalFile|null
 814          */
 815         public function getLocalFile() {
 816                 if ( is_null( $this->mLocalFile ) ) {
 817                         $nt = $this->getTitle();
 818                         $this->mLocalFile = is_null( $nt ) ? null : wfLocalFile( $nt );
 819                 }
 820                 return $this->mLocalFile;
 821         }
 822
 823         /**
 824          * If the user does not supply all necessary information in the first upload form submission (either by accident or
 825          * by design) then we may want to stash the file temporarily, get more information, and publish the file later.
 826          *
 827          * This method will stash a file in a temporary directory for later processing, and save the necessary descriptive info
 828          * into the database.
 829          * This method returns the file object, which also has a 'fileKey' property which can be passed through a form or
 830          * API request to find this stashed file again.
 831          *
 832          * @param $user User
 833          * @return UploadStashFile stashed file
 834          */
 835         public function stashFile( User $user = null ) {
 836                 // was stashSessionFile
 837                 wfProfileIn( __METHOD__ );
 838
 839                 $stash = RepoGroup::singleton()->getLocalRepo()->getUploadStash( $user );
 840                 $file = $stash->stashFile( $this->mTempPath, $this->getSourceType() );
 841                 $this->mLocalFile = $file;
 842
 843                 wfProfileOut( __METHOD__ );
 844                 return $file;
 845         }
 846
 847         /**
 848          * Stash a file in a temporary directory, returning a key which can be used to find the file again. See stashFile().
 849          *
 850          * @return String: file key
 851          */
 852         public function stashFileGetKey() {
 853                 return $this->stashFile()->getFileKey();
 854         }
 855
 856         /**
 857          * alias for stashFileGetKey, for backwards compatibility
 858          *
 859          * @return String: file key
 860          */
 861         public function stashSession() {
 862                 return $this->stashFileGetKey();
 863         }
 864
 865         /**
 866          * If we've modified the upload file we need to manually remove it
 867          * on exit to clean up.
 868          */
 869         public function cleanupTempFile() {
 870                 if ( $this->mRemoveTempFile && $this->mTempPath && file_exists( $this->mTempPath ) ) {
 871                         wfDebug( __METHOD__ . ": Removing temporary file {$this->mTempPath}\n" );
 872                         unlink( $this->mTempPath );
 873                 }
 874         }
 875
 876         public function getTempPath() {
 877                 return $this->mTempPath;
 878         }
 879
 880         /**
 881          * Split a file into a base name and all dot-delimited 'extensions'
 882          * on the end. Some web server configurations will fall back to
 883          * earlier pseudo-'extensions' to determine type and execute
 884          * scripts, so the blacklist needs to check them all.
 885          *
 886          * @param $filename string
 887          * @return array
 888          */
 889         public static function splitExtensions( $filename ) {
 890                 $bits = explode( '.', $filename );
 891                 $basename = array_shift( $bits );
 892                 return array( $basename, $bits );
 893         }
 894
 895         /**
 896          * Perform case-insensitive match against a list of file extensions.
 897          * Returns true if the extension is in the list.
 898          *
 899          * @param $ext String
 900          * @param $list Array
 901          * @return Boolean
 902          */
 903         public static function checkFileExtension( $ext, $list ) {
 904                 return in_array( strtolower( $ext ), $list );
 905         }
 906
 907         /**
 908          * Perform case-insensitive match against a list of file extensions.
 909          * Returns an array of matching extensions.
 910          *
 911          * @param $ext Array
 912          * @param $list Array
 913          * @return Boolean
 914          */
 915         public static function checkFileExtensionList( $ext, $list ) {
 916                 return array_intersect( array_map( 'strtolower', $ext ), $list );
 917         }
 918
 919         /**
 920          * Checks if the mime type of the uploaded file matches the file extension.
 921          *
 922          * @param string $mime the mime type of the uploaded file
 923          * @param string $extension the filename extension that the file is to be served with
 924          * @return Boolean
 925          */
 926         public static function verifyExtension( $mime, $extension ) {
 927                 $magic = MimeMagic::singleton();
 928
 929                 if ( !$mime || $mime == 'unknown' || $mime == 'unknown/unknown' ) {
 930                         if ( !$magic->isRecognizableExtension( $extension ) ) {
 931                                 wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
 932                                         "unrecognized extension '$extension', can't verify\n" );
 933                                 return true;
 934                         } else {
 935                                 wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; " .
 936                                         "recognized extension '$extension', so probably invalid file\n" );
 937                                 return false;
 938                         }
 939                 }
 940
 941                 $match = $magic->isMatchingExtension( $extension, $mime );
 942
 943                 if ( $match === null ) {
 944                         if ( $magic->getTypesForExtension( $extension ) !== null ) {
 945                                 wfDebug( __METHOD__ . ": No extension known for $mime, but we know a mime for $extension\n" );
 946                                 return false;
 947                         } else {
 948                                 wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file\n" );
 949                                 return true;
 950                         }
 951                 } elseif ( $match === true ) {
 952                         wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file\n" );
 953
 954                         #TODO: if it's a bitmap, make sure PHP or ImageMagic resp. can handle it!
 955                         return true;
 956
 957                 } else {
 958                         wfDebug( __METHOD__ . ": mime type $mime mismatches file extension $extension, rejecting file\n" );
 959                         return false;
 960                 }
 961         }
 962
 963         /**
 964          * Heuristic for detecting files that *could* contain JavaScript instructions or
 965          * things that may look like HTML to a browser and are thus
 966          * potentially harmful. The present implementation will produce false
 967          * positives in some situations.
 968          *
 969          * @param string $file pathname to the temporary upload file
 970          * @param string $mime the mime type of the file
 971          * @param string $extension the extension of the file
 972          * @return Boolean: true if the file contains something looking like embedded scripts
 973          */
 974         public static function detectScript( $file, $mime, $extension ) {
 975                 global $wgAllowTitlesInSVG;
 976                 wfProfileIn( __METHOD__ );
 977
 978                 # ugly hack: for text files, always look at the entire file.
 979                 # For binary field, just check the first K.
 980
 981                 if ( strpos( $mime, 'text/' ) === 0 ) {
 982                         $chunk = file_get_contents( $file );
 983                 } else {
 984                         $fp = fopen( $file, 'rb' );
 985                         $chunk = fread( $fp, 1024 );
 986                         fclose( $fp );
 987                 }
 988
 989                 $chunk = strtolower( $chunk );
 990
 991                 if ( !$chunk ) {
 992                         wfProfileOut( __METHOD__ );
 993                         return false;
 994                 }
 995
 996                 # decode from UTF-16 if needed (could be used for obfuscation).
 997                 if ( substr( $chunk, 0, 2 ) == "\xfe\xff" ) {
 998                         $enc = 'UTF-16BE';
 999                 } elseif ( substr( $chunk, 0, 2 ) == "\xff\xfe" ) {
1000                         $enc = 'UTF-16LE';
1001                 } else {
1002                         $enc = null;
1003                 }
1004
1005                 if ( $enc ) {
1006                         $chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
1007                 }
1008
1009                 $chunk = trim( $chunk );
1010
1011                 # @todo FIXME: Convert from UTF-16 if necessary!
1012                 wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff\n" );
1013
1014                 # check for HTML doctype
1015                 if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
1016                         wfProfileOut( __METHOD__ );
1017                         return true;
1018                 }
1019
1020                 // Some browsers will interpret obscure xml encodings as UTF-8, while
1021                 // PHP/expat will interpret the given encoding in the xml declaration (bug 47304)
1022                 if ( $extension == 'svg' || strpos( $mime, 'image/svg' ) === 0 ) {
1023                         if ( self::checkXMLEncodingMissmatch( $file ) ) {
1024                                 wfProfileOut( __METHOD__ );
1025                                 return true;
1026                         }
1027                 }
1028
1029                 /**
1030                  * Internet Explorer for Windows performs some really stupid file type
1031                  * autodetection which can cause it to interpret valid image files as HTML
1032                  * and potentially execute JavaScript, creating a cross-site scripting
1033                  * attack vectors.
1034                  *
1035                  * Apple's Safari browser also performs some unsafe file type autodetection
1036                  * which can cause legitimate files to be interpreted as HTML if the
1037                  * web server is not correctly configured to send the right content-type
1038                  * (or if you're really uploading plain text and octet streams!)
1039                  *
1040                  * Returns true if IE is likely to mistake the given file for HTML.
1041                  * Also returns true if Safari would mistake the given file for HTML
1042                  * when served with a generic content-type.
1043                  */
1044                 $tags = array(
1045                         '<a href',
1046                         '<body',
1047                         '<head',
1048                         '<html',   #also in safari
1049                         '<img',
1050                         '<pre',
1051                         '<script', #also in safari
1052                         '<table'
1053                 );
1054
1055                 if ( !$wgAllowTitlesInSVG && $extension !== 'svg' && $mime !== 'image/svg' ) {
1056                         $tags[] = '<title';
1057                 }
1058
1059                 foreach ( $tags as $tag ) {
1060                         if ( false !== strpos( $chunk, $tag ) ) {
1061                                 wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag\n" );
1062                                 wfProfileOut( __METHOD__ );
1063                                 return true;
1064                         }
1065                 }
1066
1067                 /*
1068                  * look for JavaScript
1069                  */
1070
1071                 # resolve entity-refs to look at attributes. may be harsh on big files... cache result?
1072                 $chunk = Sanitizer::decodeCharReferences( $chunk );
1073
1074                 # look for script-types
1075                 if ( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!sim', $chunk ) ) {
1076                         wfDebug( __METHOD__ . ": found script types\n" );
1077                         wfProfileOut( __METHOD__ );
1078                         return true;
1079                 }
1080
1081                 # look for html-style script-urls
1082                 if ( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1083                         wfDebug( __METHOD__ . ": found html-style script urls\n" );
1084                         wfProfileOut( __METHOD__ );
1085                         return true;
1086                 }
1087
1088                 # look for css-style script-urls
1089                 if ( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!sim', $chunk ) ) {
1090                         wfDebug( __METHOD__ . ": found css-style script urls\n" );
1091                         wfProfileOut( __METHOD__ );
1092                         return true;
1093                 }
1094
1095                 wfDebug( __METHOD__ . ": no scripts found\n" );
1096                 wfProfileOut( __METHOD__ );
1097                 return false;
1098         }
1099
1100
1101         /**
1102          * Check a whitelist of xml encodings that are known not to be interpreted differently
1103          * by the server's xml parser (expat) and some common browsers.
1104          *
1105          * @param string $file pathname to the temporary upload file
1106          * @return Boolean: true if the file contains an encoding that could be misinterpreted
1107          */
1108         public static function checkXMLEncodingMissmatch( $file ) {
1109                 global $wgSVGMetadataCutoff;
1110                 $contents = file_get_contents( $file, false, null, -1, $wgSVGMetadataCutoff );
1111                 $encodingRegex = '!encoding[ \t\n\r]*=[ \t\n\r]*[\'"](.*?)[\'"]!si';
1112
1113                 if ( preg_match( "!<\?xml\b(.*?)\?>!si", $contents, $matches ) ) {
1114                         if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1115                                 && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1116                         ) {
1117                                 wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1118                                 return true;
1119                         }
1120                 } elseif ( preg_match( "!<\?xml\b!si", $contents ) ) {
1121                         // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1122                         // bytes. There shouldn't be a legitimate reason for this to happen.
1123                         wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1124                         return true;
1125                 } elseif ( substr( $contents, 0, 4 ) == "\x4C\x6F\xA7\x94" ) {
1126                         // EBCDIC encoded XML
1127                         wfDebug( __METHOD__ . ": EBCDIC Encoded XML\n" );
1128                         return true;
1129                 }
1130
1131                 // It's possible the file is encoded with multi-byte encoding, so re-encode attempt to
1132                 // detect the encoding in case is specifies an encoding not whitelisted in self::$safeXmlEncodings
1133                 $attemptEncodings = array( 'UTF-16', 'UTF-16BE', 'UTF-32', 'UTF-32BE' );
1134                 foreach ( $attemptEncodings as $encoding ) {
1135                         wfSuppressWarnings();
1136                         $str = iconv( $encoding, 'UTF-8', $contents );
1137                         wfRestoreWarnings();
1138                         if ( $str != '' && preg_match( "!<\?xml\b(.*?)\?>!si", $str, $matches ) ) {
1139                                 if ( preg_match( $encodingRegex, $matches[1], $encMatch )
1140                                         && !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
1141                                 ) {
1142                                         wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'\n" );
1143                                         return true;
1144                                 }
1145                         } elseif ( $str != '' && preg_match( "!<\?xml\b!si", $str ) ) {
1146                                 // Start of XML declaration without an end in the first $wgSVGMetadataCutoff
1147                                 // bytes. There shouldn't be a legitimate reason for this to happen.
1148                                 wfDebug( __METHOD__ . ": Unmatched XML declaration start\n" );
1149                                 return true;
1150                         }
1151                 }
1152
1153                 return false;
1154         }
1155
1156         /**
1157          * @param $filename string
1158          * @return bool
1159          */
1160         protected function detectScriptInSvg( $filename ) {
1161                 $check = new XmlTypeCheck( $filename, array( $this, 'checkSvgScriptCallback' ) );
1162                 return $check->filterMatch;
1163         }
1164
1165         /**
1166          * @todo Replace this with a whitelist filter!
1167          * @param $element string
1168          * @param $attribs array
1169          * @return bool
1170          */
1171         public function checkSvgScriptCallback( $element, $attribs ) {
1172                 $strippedElement = $this->stripXmlNamespace( $element );
1173
1174                 /*
1175                  * check for elements that can contain javascript
1176                  */
1177                 if ( $strippedElement == 'script' ) {
1178                         wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file.\n" );
1179                         return true;
1180                 }
1181
1182                 # e.g., <svg xmlns="http://www.w3.org/2000/svg"> <handler xmlns:ev="http://www.w3.org/2001/xml-events" ev:event="load">alert(1)</handler> </svg>
1183                 if ( $strippedElement == 'handler' ) {
1184                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1185                         return true;
1186                 }
1187
1188                 # SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
1189                 if ( $strippedElement == 'stylesheet' ) {
1190                         wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file.\n" );
1191                         return true;
1192                 }
1193
1194                 foreach ( $attribs as $attrib => $value ) {
1195                         $stripped = $this->stripXmlNamespace( $attrib );
1196                         $value = strtolower( $value );
1197
1198                         if ( substr( $stripped, 0, 2 ) == 'on' ) {
1199                                 wfDebug( __METHOD__ . ": Found event-handler attribute '$attrib'='$value' in uploaded file.\n" );
1200                                 return true;
1201                         }
1202
1203                         # href with javascript target
1204                         if ( $stripped == 'href' && strpos( strtolower( $value ), 'javascript:' ) !== false ) {
1205                                 wfDebug( __METHOD__ . ": Found script in href attribute '$attrib'='$value' in uploaded file.\n" );
1206                                 return true;
1207                         }
1208
1209                         # href with embedded svg as target
1210                         if ( $stripped == 'href' && preg_match( '!data:[^,]*image/svg[^,]*,!sim', $value ) ) {
1211                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1212                                 return true;
1213                         }
1214
1215                         # href with embedded (text/xml) svg as target
1216                         if ( $stripped == 'href' && preg_match( '!data:[^,]*text/xml[^,]*,!sim', $value ) ) {
1217                                 wfDebug( __METHOD__ . ": Found href to embedded svg \"<$strippedElement '$attrib'='$value'...\" in uploaded file.\n" );
1218                                 return true;
1219                         }
1220
1221                         # use set/animate to add event-handler attribute to parent
1222                         if ( ( $strippedElement == 'set' || $strippedElement == 'animate' ) && $stripped == 'attributename' && substr( $value, 0, 2 ) == 'on' ) {
1223                                 wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1224                                 return true;
1225                         }
1226
1227                         # use set to add href attribute to parent element
1228                         if ( $strippedElement == 'set' && $stripped == 'attributename' && strpos( $value, 'href' ) !== false ) {
1229                                 wfDebug( __METHOD__ . ": Found svg setting href attribute '$value' in uploaded file.\n" );
1230                                 return true;
1231                         }
1232
1233                         # use set to add a remote / data / script target to an element
1234                         if ( $strippedElement == 'set' && $stripped == 'to' && preg_match( '!(http|https|data|script):!sim', $value ) ) {
1235                                 wfDebug( __METHOD__ . ": Found svg setting attribute to '$value' in uploaded file.\n" );
1236                                 return true;
1237                         }
1238
1239                         # use handler attribute with remote / data / script
1240                         if ( $stripped == 'handler' && preg_match( '!(http|https|data|script):!sim', $value ) ) {
1241                                 wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script '$attrib'='$value' in uploaded file.\n" );
1242                                 return true;
1243                         }
1244
1245                         # use CSS styles to bring in remote code
1246                         # catch url("http:..., url('http:..., url(http:..., but not url("#..., url('#..., url(#....
1247                         if ( $stripped == 'style' && preg_match_all( '!((?:font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke)\s*:\s*url\s*\(\s*["\']?\s*[^#]+.*?\))!sim', $value, $matches ) ) {
1248                                 foreach ( $matches[1] as $match ) {
1249                                         if ( !preg_match( '!(?:font|clip-path|fill|filter|marker|marker-end|marker-mid|marker-start|mask|stroke)\s*:\s*url\s*\(\s*(#|\'#|"#)!sim', $match ) ) {
1250                                                 wfDebug( __METHOD__ . ": Found svg setting a style with remote url '$attrib'='$value' in uploaded file.\n" );
1251                                                 return true;
1252                                         }
1253                                 }
1254                         }
1255
1256                         # image filters can pull in url, which could be svg that executes scripts
1257                         if ( $strippedElement == 'image' && $stripped == 'filter' && preg_match( '!url\s*\(!sim', $value ) ) {
1258                                 wfDebug( __METHOD__ . ": Found image filter with url: \"<$strippedElement $stripped='$value'...\" in uploaded file.\n" );
1259                                 return true;
1260                         }
1261
1262                 }
1263
1264                 return false; //No scripts detected
1265         }
1266
1267         /**
1268          * @param $name string
1269          * @return string
1270          */
1271         private function stripXmlNamespace( $name ) {
1272                 // 'http://www.w3.org/2000/svg:script' -> 'script'
1273                 $parts = explode( ':', strtolower( $name ) );
1274                 return array_pop( $parts );
1275         }
1276
1277         /**
1278          * Generic wrapper function for a virus scanner program.
1279          * This relies on the $wgAntivirus and $wgAntivirusSetup variables.
1280          * $wgAntivirusRequired may be used to deny upload if the scan fails.
1281          *
1282          * @param string $file pathname to the temporary upload file
1283          * @return mixed false if not virus is found, NULL if the scan fails or is disabled,
1284          *         or a string containing feedback from the virus scanner if a virus was found.
1285          *         If textual feedback is missing but a virus was found, this function returns true.
1286          */
1287         public static function detectVirus( $file ) {
1288                 global $wgAntivirus, $wgAntivirusSetup, $wgAntivirusRequired, $wgOut;
1289                 wfProfileIn( __METHOD__ );
1290
1291                 if ( !$wgAntivirus ) {
1292                         wfDebug( __METHOD__ . ": virus scanner disabled\n" );
1293                         wfProfileOut( __METHOD__ );
1294                         return null;
1295                 }
1296
1297                 if ( !$wgAntivirusSetup[$wgAntivirus] ) {
1298                         wfDebug( __METHOD__ . ": unknown virus scanner: $wgAntivirus\n" );
1299                         $wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
1300                                 array( 'virus-badscanner', $wgAntivirus ) );
1301                         wfProfileOut( __METHOD__ );
1302                         return wfMessage( 'virus-unknownscanner' )->text() . " $wgAntivirus";
1303                 }
1304
1305                 # look up scanner configuration
1306                 $command = $wgAntivirusSetup[$wgAntivirus]['command'];
1307                 $exitCodeMap = $wgAntivirusSetup[$wgAntivirus]['codemap'];
1308                 $msgPattern = isset( $wgAntivirusSetup[$wgAntivirus]['messagepattern'] ) ?
1309                         $wgAntivirusSetup[$wgAntivirus]['messagepattern'] : null;
1310
1311                 if ( strpos( $command, "%f" ) === false ) {
1312                         # simple pattern: append file to scan
1313                         $command .= " " . wfEscapeShellArg( $file );
1314                 } else {
1315                         # complex pattern: replace "%f" with file to scan
1316                         $command = str_replace( "%f", wfEscapeShellArg( $file ), $command );
1317                 }
1318
1319                 wfDebug( __METHOD__ . ": running virus scan: $command \n" );
1320
1321                 # execute virus scanner
1322                 $exitCode = false;
1323
1324                 # NOTE: there's a 50 line workaround to make stderr redirection work on windows, too.
1325                 #      that does not seem to be worth the pain.
1326                 #      Ask me (Duesentrieb) about it if it's ever needed.
1327                 $output = wfShellExec( "$command 2>&1", $exitCode );
1328
1329                 # map exit code to AV_xxx constants.
1330                 $mappedCode = $exitCode;
1331                 if ( $exitCodeMap ) {
1332                         if ( isset( $exitCodeMap[$exitCode] ) ) {
1333                                 $mappedCode = $exitCodeMap[$exitCode];
1334                         } elseif ( isset( $exitCodeMap["*"] ) ) {
1335                                 $mappedCode = $exitCodeMap["*"];
1336                         }
1337                 }
1338
1339                 /* NB: AV_NO_VIRUS is 0 but AV_SCAN_FAILED is false,
1340                  * so we need the strict equalities === and thus can't use a switch here
1341                  */
1342                 if ( $mappedCode === AV_SCAN_FAILED ) {
1343                         # scan failed (code was mapped to false by $exitCodeMap)
1344                         wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode).\n" );
1345
1346                         $output = $wgAntivirusRequired ? wfMessage( 'virus-scanfailed', array( $exitCode ) )->text() : null;
1347                 } elseif ( $mappedCode === AV_SCAN_ABORTED ) {
1348                         # scan failed because filetype is unknown (probably imune)
1349                         wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode).\n" );
1350                         $output = null;
1351                 } elseif ( $mappedCode === AV_NO_VIRUS ) {
1352                         # no virus found
1353                         wfDebug( __METHOD__ . ": file passed virus scan.\n" );
1354                         $output = false;
1355                 } else {
1356                         $output = trim( $output );
1357
1358                         if ( !$output ) {
1359                                 $output = true; #if there's no output, return true
1360                         } elseif ( $msgPattern ) {
1361                                 $groups = array();
1362                                 if ( preg_match( $msgPattern, $output, $groups ) ) {
1363                                         if ( $groups[1] ) {
1364                                                 $output = $groups[1];
1365                                         }
1366                                 }
1367                         }
1368
1369                         wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output \n" );
1370                 }
1371
1372                 wfProfileOut( __METHOD__ );
1373                 return $output;
1374         }
1375
1376         /**
1377          * Check if there's an overwrite conflict and, if so, if restrictions
1378          * forbid this user from performing the upload.
1379          *
1380          * @param $user User
1381          *
1382          * @return mixed true on success, array on failure
1383          */
1384         private function checkOverwrite( $user ) {
1385                 // First check whether the local file can be overwritten
1386                 $file = $this->getLocalFile();
1387                 if ( $file->exists() ) {
1388                         if ( !self::userCanReUpload( $user, $file ) ) {
1389                                 return array( 'fileexists-forbidden', $file->getName() );
1390                         } else {
1391                                 return true;
1392                         }
1393                 }
1394
1395                 /* Check shared conflicts: if the local file does not exist, but
1396                  * wfFindFile finds a file, it exists in a shared repository.
1397                  */
1398                 $file = wfFindFile( $this->getTitle() );
1399                 if ( $file && !$user->isAllowed( 'reupload-shared' ) ) {
1400                         return array( 'fileexists-shared-forbidden', $file->getName() );
1401                 }
1402
1403                 return true;
1404         }
1405
1406         /**
1407          * Check if a user is the last uploader
1408          *
1409          * @param $user User object
1410          * @param string $img image name
1411          * @return Boolean
1412          */
1413         public static function userCanReUpload( User $user, $img ) {
1414                 if ( $user->isAllowed( 'reupload' ) ) {
1415                         return true; // non-conditional
1416                 }
1417                 if ( !$user->isAllowed( 'reupload-own' ) ) {
1418                         return false;
1419                 }
1420                 if ( is_string( $img ) ) {
1421                         $img = wfLocalFile( $img );
1422                 }
1423                 if ( !( $img instanceof LocalFile ) ) {
1424                         return false;
1425                 }
1426
1427                 return $user->getId() == $img->getUser( 'id' );
1428         }
1429
1430         /**
1431          * Helper function that does various existence checks for a file.
1432          * The following checks are performed:
1433          * - The file exists
1434          * - Article with the same name as the file exists
1435          * - File exists with normalized extension
1436          * - The file looks like a thumbnail and the original exists
1437          *
1438          * @param $file File The File object to check
1439          * @return mixed False if the file does not exists, else an array
1440          */
1441         public static function getExistsWarning( $file ) {
1442                 if ( $file->exists() ) {
1443                         return array( 'warning' => 'exists', 'file' => $file );
1444                 }
1445
1446                 if ( $file->getTitle()->getArticleID() ) {
1447                         return array( 'warning' => 'page-exists', 'file' => $file );
1448                 }
1449
1450                 if ( $file->wasDeleted() && !$file->exists() ) {
1451                         return array( 'warning' => 'was-deleted', 'file' => $file );
1452                 }
1453
1454                 if ( strpos( $file->getName(), '.' ) == false ) {
1455                         $partname = $file->getName();
1456                         $extension = '';
1457                 } else {
1458                         $n = strrpos( $file->getName(), '.' );
1459                         $extension = substr( $file->getName(), $n + 1 );
1460                         $partname = substr( $file->getName(), 0, $n );
1461                 }
1462                 $normalizedExtension = File::normalizeExtension( $extension );
1463
1464                 if ( $normalizedExtension != $extension ) {
1465                         // We're not using the normalized form of the extension.
1466                         // Normal form is lowercase, using most common of alternate
1467                         // extensions (eg 'jpg' rather than 'JPEG').
1468                         //
1469                         // Check for another file using the normalized form...
1470                         $nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
1471                         $file_lc = wfLocalFile( $nt_lc );
1472
1473                         if ( $file_lc->exists() ) {
1474                                 return array(
1475                                         'warning' => 'exists-normalized',
1476                                         'file' => $file,
1477                                         'normalizedFile' => $file_lc
1478                                 );
1479                         }
1480                 }
1481
1482                 // Check for files with the same name but a different extension
1483                 $similarFiles = RepoGroup::singleton()->getLocalRepo()->findFilesByPrefix(
1484                                 "{$partname}.", 1 );
1485                 if ( count( $similarFiles ) ) {
1486                         return array(
1487                                 'warning' => 'exists-normalized',
1488                                 'file' => $file,
1489                                 'normalizedFile' => $similarFiles[0],
1490                         );
1491                 }
1492
1493                 if ( self::isThumbName( $file->getName() ) ) {
1494                         # Check for filenames like 50px- or 180px-, these are mostly thumbnails
1495                         $nt_thb = Title::newFromText( substr( $partname, strpos( $partname, '-' ) + 1 ) . '.' . $extension, NS_FILE );
1496                         $file_thb = wfLocalFile( $nt_thb );
1497                         if ( $file_thb->exists() ) {
1498                                 return array(
1499                                         'warning' => 'thumb',
1500                                         'file' => $file,
1501                                         'thumbFile' => $file_thb
1502                                 );
1503                         } else {
1504                                 // File does not exist, but we just don't like the name
1505                                 return array(
1506                                         'warning' => 'thumb-name',
1507                                         'file' => $file,
1508                                         'thumbFile' => $file_thb
1509                                 );
1510                         }
1511                 }
1512
1513                 foreach ( self::getFilenamePrefixBlacklist() as $prefix ) {
1514                         if ( substr( $partname, 0, strlen( $prefix ) ) == $prefix ) {
1515                                 return array(
1516                                         'warning' => 'bad-prefix',
1517                                         'file' => $file,
1518                                         'prefix' => $prefix
1519                                 );
1520                         }
1521                 }
1522
1523                 return false;
1524         }
1525
1526         /**
1527          * Helper function that checks whether the filename looks like a thumbnail
1528          * @param $filename string
1529          * @return bool
1530          */
1531         public static function isThumbName( $filename ) {
1532                 $n = strrpos( $filename, '.' );
1533                 $partname = $n ? substr( $filename, 0, $n ) : $filename;
1534                 return (
1535                                         substr( $partname, 3, 3 ) == 'px-' ||
1536                                         substr( $partname, 2, 3 ) == 'px-'
1537                                 ) &&
1538                                 preg_match( "/[0-9]{2}/", substr( $partname, 0, 2 ) );
1539         }
1540
1541         /**
1542          * Get a list of blacklisted filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
1543          *
1544          * @return array list of prefixes
1545          */
1546         public static function getFilenamePrefixBlacklist() {
1547                 $blacklist = array();
1548                 $message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
1549                 if ( !$message->isDisabled() ) {
1550                         $lines = explode( "\n", $message->plain() );
1551                         foreach ( $lines as $line ) {
1552                                 // Remove comment lines
1553                                 $comment = substr( trim( $line ), 0, 1 );
1554                                 if ( $comment == '#' || $comment == '' ) {
1555                                         continue;
1556                                 }
1557                                 // Remove additional comments after a prefix
1558                                 $comment = strpos( $line, '#' );
1559                                 if ( $comment > 0 ) {
1560                                         $line = substr( $line, 0, $comment - 1 );
1561                                 }
1562                                 $blacklist[] = trim( $line );
1563                         }
1564                 }
1565                 return $blacklist;
1566         }
1567
1568         /**
1569          * Gets image info about the file just uploaded.
1570          *
1571          * Also has the effect of setting metadata to be an 'indexed tag name' in returned API result if
1572          * 'metadata' was requested. Oddly, we have to pass the "result" object down just so it can do that
1573          * with the appropriate format, presumably.
1574          *
1575          * @param $result ApiResult:
1576          * @return Array: image info
1577          */
1578         public function getImageInfo( $result ) {
1579                 $file = $this->getLocalFile();
1580                 // TODO This cries out for refactoring. We really want to say $file->getAllInfo(); here.
1581                 // Perhaps "info" methods should be moved into files, and the API should just wrap them in queries.
1582                 if ( $file instanceof UploadStashFile ) {
1583                         $imParam = ApiQueryStashImageInfo::getPropertyNames();
1584                         $info = ApiQueryStashImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1585                 } else {
1586                         $imParam = ApiQueryImageInfo::getPropertyNames();
1587                         $info = ApiQueryImageInfo::getInfo( $file, array_flip( $imParam ), $result );
1588                 }
1589                 return $info;
1590         }
1591
1592         /**
1593          * @param $error array
1594          * @return Status
1595          */
1596         public function convertVerifyErrorToStatus( $error ) {
1597                 $code = $error['status'];
1598                 unset( $code['status'] );
1599                 return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
1600         }
1601
1602         /**
1603          * @param $forType null|string
1604          * @return int
1605          */
1606         public static function getMaxUploadSize( $forType = null ) {
1607                 global $wgMaxUploadSize;
1608
1609                 if ( is_array( $wgMaxUploadSize ) ) {
1610                         if ( !is_null( $forType ) && isset( $wgMaxUploadSize[$forType] ) ) {
1611                                 return $wgMaxUploadSize[$forType];
1612                         } else {
1613                                 return $wgMaxUploadSize['*'];
1614                         }
1615                 } else {
1616                         return intval( $wgMaxUploadSize );
1617                 }
1618         }
1619
1620         /**
1621          * Get the current status of a chunked upload (used for polling).
1622          * The status will be read from the *current* user session.
1623          * @param $statusKey string
1624          * @return Array|bool
1625          */
1626         public static function getSessionStatus( $statusKey ) {
1627                 return isset( $_SESSION[self::SESSION_STATUS_KEY][$statusKey] )
1628                         ? $_SESSION[self::SESSION_STATUS_KEY][$statusKey]
1629                         : false;
1630         }
1631
1632         /**
1633          * Set the current status of a chunked upload (used for polling).
1634          * The status will be stored in the *current* user session.
1635          * @param $statusKey string
1636          * @param $value array|false
1637          * @return void
1638          */
1639         public static function setSessionStatus( $statusKey, $value ) {
1640                 if ( $value === false ) {
1641                         unset( $_SESSION[self::SESSION_STATUS_KEY][$statusKey] );
1642                 } else {
1643                         $_SESSION[self::SESSION_STATUS_KEY][$statusKey] = $value;
1644                 }
1645         }
1646 }