includes/upload/UploadBase.php
<?php
/**
* Base class for the backend of file upload.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Upload
*/
use MediaWiki\Context\RequestContext;
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\HookContainer\ProtectedHookAccessorTrait;
use MediaWiki\Logger\LoggerFactory;
use MediaWiki\MainConfigNames;
use MediaWiki\MediaWikiServices;
use MediaWiki\Parser\Sanitizer;
use MediaWiki\Permissions\Authority;
use MediaWiki\Permissions\PermissionStatus;
use MediaWiki\Request\WebRequest;
use MediaWiki\Shell\Shell;
use MediaWiki\Status\Status;
use MediaWiki\Title\Title;
use MediaWiki\User\User;
use MediaWiki\User\UserIdentity;
use Wikimedia\AtEase\AtEase;
/**
* @defgroup Upload Upload related
*/
/**
* @ingroup Upload
*
* UploadBase and subclasses are the backend of MediaWiki's file uploads.
* The frontends are formed by ApiUpload and SpecialUpload.
*
* @stable to extend
*
* @author Brooke Vibber
* @author Bryan Tong Minh
* @author Michael Dale
*/
abstract class UploadBase {
use ProtectedHookAccessorTrait;
/** @var string|null Local file system path to the file to upload (or a local copy) */
protected $mTempPath;
/** @var TempFSFile|null Wrapper to handle deleting the temp file */
protected $tempFileObj;
/** @var string|null */
protected $mDesiredDestName;
/** @var string|null */
protected $mDestName;
/** @var bool|null */
protected $mRemoveTempFile;
/** @var string|null */
protected $mSourceType;
/** @var Title|false|null */
protected $mTitle = false;
/** @var int */
protected $mTitleError = 0;
/** @var string|null */
protected $mFilteredName;
/** @var string|null */
protected $mFinalExtension;
/** @var LocalFile|null */
protected $mLocalFile;
/** @var UploadStashFile|null */
protected $mStashFile;
/** @var int|null */
protected $mFileSize;
/** @var array|null */
protected $mFileProps;
/** @var string[] */
protected $mBlackListedExtensions;
/** @var bool|null */
protected $mJavaDetected;
/** @var string|false */
protected $mSVGNSError;
protected static $safeXmlEncodings = [
'UTF-8',
'US-ASCII',
'ISO-8859-1',
'ISO-8859-2',
'UTF-16',
'UTF-32',
'WINDOWS-1250',
'WINDOWS-1251',
'WINDOWS-1252',
'WINDOWS-1253',
'WINDOWS-1254',
'WINDOWS-1255',
'WINDOWS-1256',
'WINDOWS-1257',
'WINDOWS-1258',
];
public const SUCCESS = 0;
public const OK = 0;
public const EMPTY_FILE = 3;
public const MIN_LENGTH_PARTNAME = 4;
public const ILLEGAL_FILENAME = 5;
public const OVERWRITE_EXISTING_FILE = 7; # Not used anymore; handled by verifyTitlePermissions()
public const FILETYPE_MISSING = 8;
public const FILETYPE_BADTYPE = 9;
public const VERIFICATION_ERROR = 10;
public const HOOK_ABORTED = 11;
public const FILE_TOO_LARGE = 12;
public const WINDOWS_NONASCII_FILENAME = 13;
public const FILENAME_TOO_LONG = 14;
private const CODE_TO_STATUS = [
self::EMPTY_FILE => 'empty-file',
self::FILE_TOO_LARGE => 'file-too-large',
self::FILETYPE_MISSING => 'filetype-missing',
self::FILETYPE_BADTYPE => 'filetype-banned',
self::MIN_LENGTH_PARTNAME => 'filename-tooshort',
self::ILLEGAL_FILENAME => 'illegal-filename',
self::OVERWRITE_EXISTING_FILE => 'overwrite',
self::VERIFICATION_ERROR => 'verification-error',
self::HOOK_ABORTED => 'hookaborted',
self::WINDOWS_NONASCII_FILENAME => 'windows-nonascii-filename',
self::FILENAME_TOO_LONG => 'filename-toolong',
];
/**
* @param int $error
* @return string
*/
public function getVerificationErrorCode( $error ) {
return self::CODE_TO_STATUS[$error] ?? 'unknown-error';
}
/**
* Returns true if uploads are enabled.
* Can be override by subclasses.
* @stable to override
* @return bool
*/
public static function isEnabled() {
$enableUploads = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::EnableUploads );
return $enableUploads && wfIniGetBool( 'file_uploads' );
}
/**
* Returns true if the user can use this upload module or else a string
* identifying the missing permission.
* Can be overridden by subclasses.
*
* @param Authority $performer
* @return bool|string
*/
public static function isAllowed( Authority $performer ) {
foreach ( [ 'upload', 'edit' ] as $permission ) {
if ( !$performer->isAllowed( $permission ) ) {
return $permission;
}
}
return true;
}
/**
* Returns true if the user has surpassed the upload rate limit, false otherwise.
*
* @deprecated since 1.41, use verifyTitlePermissions() instead.
* Rate limit checks are now implicit in permission checks.
*
* @param User $user
* @return bool
*/
public static function isThrottled( $user ) {
wfDeprecated( __METHOD__, '1.41' );
return $user->pingLimiter( 'upload' );
}
/** @var string[] Upload handlers. Should probably just be a configuration variable. */
private static $uploadHandlers = [ 'Stash', 'File', 'Url' ];
/**
* Create a form of UploadBase depending on wpSourceType and initializes it.
*
* @param WebRequest &$request
* @param string|null $type
* @return null|self
*/
public static function createFromRequest( &$request, $type = null ) {
$type = $type ?: $request->getVal( 'wpSourceType', 'File' );
if ( !$type ) {
return null;
}
// Get the upload class
$type = ucfirst( $type );
// Give hooks the chance to handle this request
/** @var self|null $className */
$className = null;
( new HookRunner( MediaWikiServices::getInstance()->getHookContainer() ) )
// @phan-suppress-next-line PhanTypeMismatchArgument Type mismatch on pass-by-ref args
->onUploadCreateFromRequest( $type, $className );
if ( $className === null ) {
$className = 'UploadFrom' . $type;
wfDebug( __METHOD__ . ": class name: $className" );
if ( !in_array( $type, self::$uploadHandlers ) ) {
return null;
}
}
if ( !$className::isEnabled() || !$className::isValidRequest( $request ) ) {
return null;
}
/** @var self $handler */
$handler = new $className;
$handler->initializeFromRequest( $request );
return $handler;
}
/**
* Check whether a request if valid for this handler.
* @param WebRequest $request
* @return bool
*/
public static function isValidRequest( $request ) {
return false;
}
/**
* Get the desired destination name.
* @return string|null
*/
public function getDesiredDestName() {
return $this->mDesiredDestName;
}
/**
* @stable to call
*/
public function __construct() {
}
/**
* Returns the upload type. Should be overridden by child classes.
*
* @since 1.18
* @stable to override
* @return string|null
*/
public function getSourceType() {
return null;
}
/**
* @param string $name The desired destination name
* @param string|null $tempPath Callers should make sure this is not a storage path
* @param int|null $fileSize
* @param bool $removeTempFile (false) remove the temporary file?
*/
public function initializePathInfo( $name, $tempPath, $fileSize, $removeTempFile = false ) {
$this->mDesiredDestName = $name;
if ( FileBackend::isStoragePath( $tempPath ) ) {
throw new InvalidArgumentException( __METHOD__ . " given storage path `$tempPath`." );
}
$this->setTempFile( $tempPath, $fileSize );
$this->mRemoveTempFile = $removeTempFile;
}
/**
* Initialize from a WebRequest. Override this in a subclass.
*
* @param WebRequest &$request
*/
abstract public function initializeFromRequest( &$request );
/**
* @param string|null $tempPath File system path to temporary file containing the upload
* @param int|null $fileSize
*/
protected function setTempFile( $tempPath, $fileSize = null ) {
$this->mTempPath = $tempPath ?? '';
$this->mFileSize = $fileSize ?: null;
$this->mFileProps = null;
if ( strlen( $this->mTempPath ) && file_exists( $this->mTempPath ) ) {
$this->tempFileObj = new TempFSFile( $this->mTempPath );
if ( !$fileSize ) {
$this->mFileSize = filesize( $this->mTempPath );
}
} else {
$this->tempFileObj = null;
}
}
/**
* Fetch the file. Usually a no-op.
* @stable to override
* @return Status
*/
public function fetchFile() {
return Status::newGood();
}
/**
* Perform checks to see if the file can be fetched. Usually a no-op.
* @stable to override
* @return Status
*/
public function canFetchFile() {
return Status::newGood();
}
/**
* Return true if the file is empty.
* @return bool
*/
public function isEmptyFile() {
return !$this->mFileSize;
}
/**
* Return the file size.
* @return int
*/
public function getFileSize() {
return $this->mFileSize;
}
/**
* Get the base 36 SHA1 of the file.
* @stable to override
* @return string|false
*/
public function getTempFileSha1Base36() {
// Use cached version if we already have it.
if ( $this->mFileProps && is_string( $this->mFileProps['sha1'] ) ) {
return $this->mFileProps['sha1'];
}
return FSFile::getSha1Base36FromPath( $this->mTempPath );
}
/**
* @param string $srcPath The source path
* @return string|false The real path if it was a virtual URL Returns false on failure
*/
public function getRealPath( $srcPath ) {
$repo = MediaWikiServices::getInstance()->getRepoGroup()->getLocalRepo();
if ( FileRepo::isVirtualUrl( $srcPath ) ) {
/** @todo Just make uploads work with storage paths UploadFromStash
* loads files via virtual URLs.
*/
$tmpFile = $repo->getLocalCopy( $srcPath );
if ( $tmpFile ) {
$tmpFile->bind( $this ); // keep alive with $this
}
$path = $tmpFile ? $tmpFile->getPath() : false;
} else {
$path = $srcPath;
}
return $path;
}
/**
* Verify whether the upload is sensible.
*
* Return a status array representing the outcome of the verification.
* Possible keys are:
* - 'status': set to self::OK in case of success, or to one of the error constants defined in
* this class in case of failure
* - 'max': set to the maximum allowed file size ($wgMaxUploadSize) if the upload is too large
* - 'details': set to error details if the file type is valid but contents are corrupt
* - 'filtered': set to the sanitized file name if the requested file name is invalid
* - 'finalExt': set to the file's file extension if it is not an allowed file extension
* - 'blacklistedExt': set to the list of disallowed file extensions if the current file extension
* is not allowed for uploads and the list is not empty
*
* @stable to override
* @return mixed[] array representing the result of the verification
*/
public function verifyUpload() {
/**
* If there was no filename or a zero size given, give up quick.
*/
if ( $this->isEmptyFile() ) {
return [ 'status' => self::EMPTY_FILE ];
}
/**
* Honor $wgMaxUploadSize
*/
$maxSize = self::getMaxUploadSize( $this->getSourceType() );
if ( $this->mFileSize > $maxSize ) {
return [
'status' => self::FILE_TOO_LARGE,
'max' => $maxSize,
];
}
/**
* Look at the contents of the file; if we can recognize the
* type, but it's corrupt or data of the wrong type, we should
* probably not accept it.
*/
$verification = $this->verifyFile();
if ( $verification !== true ) {
return [
'status' => self::VERIFICATION_ERROR,
'details' => $verification
];
}
/**
* Make sure this file can be created
*/
$result = $this->validateName();
if ( $result !== true ) {
return $result;
}
return [ 'status' => self::OK ];
}
/**
* Verify that the name is valid and, if necessary, that we can overwrite
*
* @return array|bool True if valid, otherwise an array with 'status'
* and other keys
*/
public function validateName() {
$nt = $this->getTitle();
if ( $nt === null ) {
$result = [ 'status' => $this->mTitleError ];
if ( $this->mTitleError === self::ILLEGAL_FILENAME ) {
$result['filtered'] = $this->mFilteredName;
}
if ( $this->mTitleError === self::FILETYPE_BADTYPE ) {
$result['finalExt'] = $this->mFinalExtension;
if ( count( $this->mBlackListedExtensions ) ) {
$result['blacklistedExt'] = $this->mBlackListedExtensions;
}
}
return $result;
}
$this->mDestName = $this->getLocalFile()->getName();
return true;
}
/**
* Verify the MIME type.
*
* @note Only checks that it is not an evil MIME.
* The "does it have the correct file extension given its MIME type?" check is in verifyFile.
* @param string $mime Representing the MIME
* @return array|bool True if the file is verified, an array otherwise
*/
protected function verifyMimeType( $mime ) {
$verifyMimeType = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::VerifyMimeType );
if ( $verifyMimeType ) {
wfDebug( "mime: <$mime> extension: <{$this->mFinalExtension}>" );
$mimeTypeExclusions = MediaWikiServices::getInstance()->getMainConfig()
->get( MainConfigNames::MimeTypeExclusions );
if ( self::checkFileExtension( $mime, $mimeTypeExclusions ) ) {
return [ 'filetype-badmime', $mime ];
}
}
return true;
}
/**
* Verifies that it's ok to include the uploaded file
*
* @return array|true True of the file is verified, array otherwise.
*/
protected function verifyFile() {
$config = MediaWikiServices::getInstance()->getMainConfig();
$verifyMimeType = $config->get( MainConfigNames::VerifyMimeType );
$disableUploadScriptChecks = $config->get( MainConfigNames::DisableUploadScriptChecks );
$status = $this->verifyPartialFile();
if ( $status !== true ) {
return $status;
}
// Calculating props calculates the sha1 which is expensive.
// reuse props if we already have them
if ( !is_array( $this->mFileProps ) ) {
$mwProps = new MWFileProps( MediaWikiServices::getInstance()->getMimeAnalyzer() );
$this->mFileProps = $mwProps->getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
}
$mime = $this->mFileProps['mime'];
if ( $verifyMimeType ) {
# XXX: Missing extension will be caught by validateName() via getTitle()
if ( (string)$this->mFinalExtension !== '' &&
!self::verifyExtension( $mime, $this->mFinalExtension )
) {
return [ 'filetype-mime-mismatch', $this->mFinalExtension, $mime ];
}
}
# check for htmlish code and javascript
if ( !$disableUploadScriptChecks ) {
if ( $this->mFinalExtension === 'svg' || $mime === 'image/svg+xml' ) {
$svgStatus = $this->detectScriptInSvg( $this->mTempPath, false );
if ( $svgStatus !== false ) {
return $svgStatus;
}
}
}
$handler = MediaHandler::getHandler( $mime );
if ( $handler ) {
$handlerStatus = $handler->verifyUpload( $this->mTempPath );
if ( !$handlerStatus->isOK() ) {
$errors = $handlerStatus->getErrorsArray();
return reset( $errors );
}
}
$error = true;
$this->getHookRunner()->onUploadVerifyFile( $this, $mime, $error );
if ( $error !== true ) {
if ( !is_array( $error ) ) {
$error = [ $error ];
}
return $error;
}
wfDebug( __METHOD__ . ": all clear; passing." );
return true;
}
/**
* A verification routine suitable for partial files
*
* Runs the deny list checks, but not any checks that may
* assume the entire file is present.
*
* @return array|true True, if the file is valid, else an array with error message key.
* @phan-return non-empty-array|true
*/
protected function verifyPartialFile() {
$config = MediaWikiServices::getInstance()->getMainConfig();
$disableUploadScriptChecks = $config->get( MainConfigNames::DisableUploadScriptChecks );
# getTitle() sets some internal parameters like $this->mFinalExtension
$this->getTitle();
// Calculating props calculates the sha1 which is expensive.
// reuse props if we already have them (e.g. During stashed upload)
if ( !is_array( $this->mFileProps ) ) {
$mwProps = new MWFileProps( MediaWikiServices::getInstance()->getMimeAnalyzer() );
$this->mFileProps = $mwProps->getPropsFromPath( $this->mTempPath, $this->mFinalExtension );
}
# check MIME type, if desired
$mime = $this->mFileProps['file-mime'];
$status = $this->verifyMimeType( $mime );
if ( $status !== true ) {
return $status;
}
# check for htmlish code and javascript
if ( !$disableUploadScriptChecks ) {
if ( self::detectScript( $this->mTempPath, $mime, $this->mFinalExtension ) ) {
return [ 'uploadscripted' ];
}
if ( $this->mFinalExtension === 'svg' || $mime === 'image/svg+xml' ) {
$svgStatus = $this->detectScriptInSvg( $this->mTempPath, true );
if ( $svgStatus !== false ) {
return $svgStatus;
}
}
}
# Scan the uploaded file for viruses
$virus = self::detectVirus( $this->mTempPath );
if ( $virus ) {
return [ 'uploadvirus', $virus ];
}
return true;
}
/**
* Callback for ZipDirectoryReader to detect Java class files.
*
* @param array $entry
*/
public function zipEntryCallback( $entry ) {
$names = [ $entry['name'] ];
// If there is a null character, cut off the name at it, because JDK's
// ZIP_GetEntry() uses strcmp() if the name hashes match. If a file name
// were constructed which had ".class\0" followed by a string chosen to
// make the hash collide with the truncated name, that file could be
// returned in response to a request for the .class file.
$nullPos = strpos( $entry['name'], "\000" );
if ( $nullPos !== false ) {
$names[] = substr( $entry['name'], 0, $nullPos );
}
// If there is a trailing slash in the file name, we have to strip it,
// because that's what ZIP_GetEntry() does.
if ( preg_grep( '!\.class/?$!', $names ) ) {
$this->mJavaDetected = true;
}
}
/**
* Alias for verifyTitlePermissions. The function was originally
* 'verifyPermissions', but that suggests it's checking the user, when it's
* really checking the title + user combination.
*
* @param Authority $performer to verify the permissions against
* @return array|bool An array as returned by getPermissionErrors or true
* in case the user has proper permissions.
*/
public function verifyPermissions( Authority $performer ) {
return $this->verifyTitlePermissions( $performer );
}
/**
* Check whether the user can edit, upload and create the image. This
* checks only against the current title; if it returns errors, it may
* very well be that another title will not give errors. Therefore
* isAllowed() should be called as well for generic is-user-blocked or
* can-user-upload checking.
*
* @param Authority $performer to verify the permissions against
* @return array|bool An array as returned by getPermissionErrors or true
* in case the user has proper permissions.
*/
public function verifyTitlePermissions( Authority $performer ) {
/**
* If the image is protected, non-sysop users won't be able
* to modify it by uploading a new revision.
*/
$nt = $this->getTitle();
if ( $nt === null ) {
return true;
}
$status = PermissionStatus::newEmpty();
$performer->authorizeWrite( 'edit', $nt, $status );
$performer->authorizeWrite( 'upload', $nt, $status );
if ( !$status->isGood() ) {
return $status->toLegacyErrorArray();
}
$overwriteError = $this->checkOverwrite( $performer );
if ( $overwriteError !== true ) {
return [ $overwriteError ];
}
return true;
}
/**
* Check for non fatal problems with the file.
*
* This should not assume that mTempPath is set.
*
* @param User|null $user Accepted since 1.35
*
* @return mixed[] Array of warnings
*/
public function checkWarnings( $user = null ) {
if ( $user === null ) {
// TODO check uses and hard deprecate
$user = RequestContext::getMain()->getUser();
}
$warnings = [];
$localFile = $this->getLocalFile();
$localFile->load( IDBAccessObject::READ_LATEST );
$filename = $localFile->getName();
$hash = $this->getTempFileSha1Base36();
$badFileName = $this->checkBadFileName( $filename, $this->mDesiredDestName );
if ( $badFileName !== null ) {
$warnings['badfilename'] = $badFileName;
}
$unwantedFileExtensionDetails = $this->checkUnwantedFileExtensions( (string)$this->mFinalExtension );
if ( $unwantedFileExtensionDetails !== null ) {
$warnings['filetype-unwanted-type'] = $unwantedFileExtensionDetails;
}
$fileSizeWarnings = $this->checkFileSize( $this->mFileSize );
if ( $fileSizeWarnings ) {
$warnings = array_merge( $warnings, $fileSizeWarnings );
}
$localFileExistsWarnings = $this->checkLocalFileExists( $localFile, $hash );
if ( $localFileExistsWarnings ) {
$warnings = array_merge( $warnings, $localFileExistsWarnings );
}
if ( $this->checkLocalFileWasDeleted( $localFile ) ) {
$warnings['was-deleted'] = $filename;
}
// If a file with the same name exists locally then the local file has already been tested
// for duplication of content
$ignoreLocalDupes = isset( $warnings['exists'] );
$dupes = $this->checkAgainstExistingDupes( $hash, $ignoreLocalDupes );
if ( $dupes ) {
$warnings['duplicate'] = $dupes;
}
$archivedDupes = $this->checkAgainstArchiveDupes( $hash, $user );
if ( $archivedDupes !== null ) {
$warnings['duplicate-archive'] = $archivedDupes;
}
return $warnings;
}
/**
* Convert the warnings array returned by checkWarnings() to something that
* can be serialized. File objects will be converted to an associative array
* with the following keys:
*
* - fileName: The name of the file
* - timestamp: The upload timestamp
*
* @param mixed[] $warnings
* @return mixed[]
*/
public static function makeWarningsSerializable( $warnings ) {
array_walk_recursive( $warnings, static function ( &$param, $key ) {
if ( $param instanceof File ) {
$param = [
'fileName' => $param->getName(),
'timestamp' => $param->getTimestamp()
];
} elseif ( is_object( $param ) ) {
throw new InvalidArgumentException(
'UploadBase::makeWarningsSerializable: ' .
'Unexpected object of class ' . get_class( $param ) );
}
} );
return $warnings;
}
/**
* Convert the serialized warnings array created by makeWarningsSerializable()
* back to the output of checkWarnings().
*
* @param mixed[] $warnings
* @return mixed[]
*/
public static function unserializeWarnings( $warnings ) {
foreach ( $warnings as $key => $value ) {
if ( is_array( $value ) ) {
if ( isset( $value['fileName'] ) && isset( $value['timestamp'] ) ) {
$warnings[$key] = MediaWikiServices::getInstance()->getRepoGroup()->findFile(
$value['fileName'],
[ 'time' => $value['timestamp'] ]
);
} else {
$warnings[$key] = self::unserializeWarnings( $value );
}
}
}
return $warnings;
}
/**
* Check whether the resulting filename is different from the desired one,
* but ignore things like ucfirst() and spaces/underscore things
*
* @param string $filename
* @param string $desiredFileName
*
* @return string|null String that was determined to be bad or null if the filename is okay
*/
private function checkBadFileName( $filename, $desiredFileName ) {
$comparableName = str_replace( ' ', '_', $desiredFileName );
$comparableName = Title::capitalize( $comparableName, NS_FILE );
if ( $desiredFileName != $filename && $comparableName != $filename ) {
return $filename;
}
return null;
}
/**
* @param string $fileExtension The file extension to check
*
* @return array|null array with the following keys:
* 0 => string The final extension being used
* 1 => string[] The extensions that are allowed
* 2 => int The number of extensions that are allowed.
*/
private function checkUnwantedFileExtensions( $fileExtension ) {
$checkFileExtensions = MediaWikiServices::getInstance()->getMainConfig()
->get( MainConfigNames::CheckFileExtensions );
$fileExtensions = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::FileExtensions );
if ( $checkFileExtensions ) {
$extensions = array_unique( $fileExtensions );
if ( !self::checkFileExtension( $fileExtension, $extensions ) ) {
return [
$fileExtension,
Message::listParam( $extensions, 'comma' ),
count( $extensions )
];
}
}
return null;
}
/**
* @param int $fileSize
*
* @return array warnings
*/
private function checkFileSize( $fileSize ) {
$uploadSizeWarning = MediaWikiServices::getInstance()->getMainConfig()
->get( MainConfigNames::UploadSizeWarning );
$warnings = [];
if ( $uploadSizeWarning && ( $fileSize > $uploadSizeWarning ) ) {
$warnings['large-file'] = [
Message::sizeParam( $uploadSizeWarning ),
Message::sizeParam( $fileSize ),
];
}
if ( $fileSize == 0 ) {
$warnings['empty-file'] = true;
}
return $warnings;
}
/**
* @param LocalFile $localFile
* @param string|false $hash sha1 hash of the file to check
*
* @return array warnings
*/
private function checkLocalFileExists( LocalFile $localFile, $hash ) {
$warnings = [];
$exists = self::getExistsWarning( $localFile );
if ( $exists !== false ) {
$warnings['exists'] = $exists;
// check if file is an exact duplicate of current file version
if ( $hash !== false && $hash === $localFile->getSha1() ) {
$warnings['no-change'] = $localFile;
}
// check if file is an exact duplicate of older versions of this file
$history = $localFile->getHistory();
foreach ( $history as $oldFile ) {
if ( $hash === $oldFile->getSha1() ) {
$warnings['duplicate-version'][] = $oldFile;
}
}
}
return $warnings;
}
private function checkLocalFileWasDeleted( LocalFile $localFile ) {
return $localFile->wasDeleted() && !$localFile->exists();
}
/**
* @param string|false $hash sha1 hash of the file to check
* @param bool $ignoreLocalDupes True to ignore local duplicates
*
* @return File[] Duplicate files, if found.
*/
private function checkAgainstExistingDupes( $hash, $ignoreLocalDupes ) {
if ( $hash === false ) {
return [];
}
$dupes = MediaWikiServices::getInstance()->getRepoGroup()->findBySha1( $hash );
$title = $this->getTitle();
foreach ( $dupes as $key => $dupe ) {
if (
( $dupe instanceof LocalFile ) &&
$ignoreLocalDupes &&
$title->equals( $dupe->getTitle() )
) {
unset( $dupes[$key] );
}
}
return $dupes;
}
/**
* @param string|false $hash sha1 hash of the file to check
* @param Authority $performer
*
* @return string|null Name of the dupe or empty string if discovered (depending on visibility)
* null if the check discovered no dupes.
*/
private function checkAgainstArchiveDupes( $hash, Authority $performer ) {
if ( $hash === false ) {
return null;
}
$archivedFile = new ArchivedFile( null, 0, '', $hash );
if ( $archivedFile->getID() > 0 ) {
if ( $archivedFile->userCan( File::DELETED_FILE, $performer ) ) {
return $archivedFile->getName();
}
return '';
}
return null;
}
/**
* Really perform the upload. Stores the file in the local repo, watches
* if necessary and runs the UploadComplete hook.
*
* @param string $comment
* @param string|false $pageText
* @param bool $watch Whether the file page should be added to user's watchlist.
* (This doesn't check $user's permissions.)
* @param User $user
* @param string[] $tags Change tags to add to the log entry and page revision.
* (This doesn't check $user's permissions.)
* @param string|null $watchlistExpiry Optional watchlist expiry timestamp in any format
* acceptable to wfTimestamp().
* @return Status Indicating the whether the upload succeeded.
*
* @since 1.35 Accepts $watchlistExpiry parameter.
*/
public function performUpload(
$comment, $pageText, $watch, $user, $tags = [], ?string $watchlistExpiry = null
) {
$this->getLocalFile()->load( IDBAccessObject::READ_LATEST );
$props = $this->mFileProps;
$error = null;
$this->getHookRunner()->onUploadVerifyUpload( $this, $user, $props, $comment, $pageText, $error );
if ( $error ) {
if ( !is_array( $error ) ) {
$error = [ $error ];
}
return Status::newFatal( ...$error );
}
$status = $this->getLocalFile()->upload(
$this->mTempPath,
$comment,
$pageText !== false ? $pageText : '',
File::DELETE_SOURCE,
$props,
false,
$user,
$tags
);
if ( $status->isGood() ) {
if ( $watch ) {
MediaWikiServices::getInstance()->getWatchlistManager()->addWatchIgnoringRights(
$user,
$this->getLocalFile()->getTitle(),
$watchlistExpiry
);
}
$this->getHookRunner()->onUploadComplete( $this );
$this->postProcessUpload();
}
return $status;
}
/**
* Perform extra steps after a successful upload.
*
* @stable to override
* @since 1.25
*/
public function postProcessUpload() {
}
/**
* Returns the title of the file to be uploaded. Sets mTitleError in case
* the name was illegal.
*
* @return Title|null The title of the file or null in case the name was illegal
*/
public function getTitle() {
if ( $this->mTitle !== false ) {
return $this->mTitle;
}
if ( !is_string( $this->mDesiredDestName ) ) {
$this->mTitleError = self::ILLEGAL_FILENAME;
$this->mTitle = null;
return $this->mTitle;
}
/* Assume that if a user specified File:Something.jpg, this is an error
* and that the namespace prefix needs to be stripped of.
*/
$title = Title::newFromText( $this->mDesiredDestName );
if ( $title && $title->getNamespace() === NS_FILE ) {
$this->mFilteredName = $title->getDBkey();
} else {
$this->mFilteredName = $this->mDesiredDestName;
}
# oi_archive_name is max 255 bytes, which include a timestamp and an
# exclamation mark, so restrict file name to 240 bytes.
if ( strlen( $this->mFilteredName ) > 240 ) {
$this->mTitleError = self::FILENAME_TOO_LONG;
$this->mTitle = null;
return $this->mTitle;
}
/**
* Chop off any directories in the given filename. Then
* filter out illegal characters, and try to make a legible name
* out of it. We'll strip some silently that Title would die on.
*/
$this->mFilteredName = wfStripIllegalFilenameChars( $this->mFilteredName );
/* Normalize to title form before we do any further processing */
$nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
if ( $nt === null ) {
$this->mTitleError = self::ILLEGAL_FILENAME;
$this->mTitle = null;
return $this->mTitle;
}
$this->mFilteredName = $nt->getDBkey();
/**
* We'll want to prevent against *any* 'extension', and use
* only the final one for the allow list.
*/
[ $partname, $ext ] = self::splitExtensions( $this->mFilteredName );
if ( $ext !== [] ) {
$this->mFinalExtension = trim( end( $ext ) );
} else {
$this->mFinalExtension = '';
// No extension, try guessing one from the temporary file
// FIXME: Sometimes we mTempPath isn't set yet here, possibly due to an unrealistic
// or incomplete test case in UploadBaseTest (T272328)
if ( $this->mTempPath !== null ) {
$magic = MediaWikiServices::getInstance()->getMimeAnalyzer();
$mime = $magic->guessMimeType( $this->mTempPath );
if ( $mime !== 'unknown/unknown' ) {
# Get a space separated list of extensions
$mimeExt = $magic->getExtensionFromMimeTypeOrNull( $mime );
if ( $mimeExt !== null ) {
# Set the extension to the canonical extension
$this->mFinalExtension = $mimeExt;
# Fix up the other variables
$this->mFilteredName .= ".{$this->mFinalExtension}";
$nt = Title::makeTitleSafe( NS_FILE, $this->mFilteredName );
$ext = [ $this->mFinalExtension ];
}
}
}
}
// Don't allow users to override the list of prohibited file extensions (check file extension)
$config = MediaWikiServices::getInstance()->getMainConfig();
$checkFileExtensions = $config->get( MainConfigNames::CheckFileExtensions );
$strictFileExtensions = $config->get( MainConfigNames::StrictFileExtensions );
$fileExtensions = $config->get( MainConfigNames::FileExtensions );
$prohibitedFileExtensions = $config->get( MainConfigNames::ProhibitedFileExtensions );
$badList = self::checkFileExtensionList( $ext, $prohibitedFileExtensions );
if ( $this->mFinalExtension == '' ) {
$this->mTitleError = self::FILETYPE_MISSING;
$this->mTitle = null;
return $this->mTitle;
}
if ( $badList ||
( $checkFileExtensions && $strictFileExtensions &&
!self::checkFileExtension( $this->mFinalExtension, $fileExtensions ) )
) {
$this->mBlackListedExtensions = $badList;
$this->mTitleError = self::FILETYPE_BADTYPE;
$this->mTitle = null;
return $this->mTitle;
}
// Windows may be broken with special characters, see T3780
if ( !preg_match( '/^[\x0-\x7f]*$/', $nt->getText() )
&& !MediaWikiServices::getInstance()->getRepoGroup()
->getLocalRepo()->backendSupportsUnicodePaths()
) {
$this->mTitleError = self::WINDOWS_NONASCII_FILENAME;
$this->mTitle = null;
return $this->mTitle;
}
# If there was more than one file "extension", reassemble the base
# filename to prevent bogus complaints about length
if ( count( $ext ) > 1 ) {
$iterations = count( $ext ) - 1;
for ( $i = 0; $i < $iterations; $i++ ) {
$partname .= '.' . $ext[$i];
}
}
if ( strlen( $partname ) < 1 ) {
$this->mTitleError = self::MIN_LENGTH_PARTNAME;
$this->mTitle = null;
return $this->mTitle;
}
$this->mTitle = $nt;
return $this->mTitle;
}
/**
* Return the local file and initializes if necessary.
*
* @stable to override
* @return LocalFile|null
*/
public function getLocalFile() {
if ( $this->mLocalFile === null ) {
$nt = $this->getTitle();
$this->mLocalFile = $nt === null
? null
: MediaWikiServices::getInstance()->getRepoGroup()->getLocalRepo()->newFile( $nt );
}
return $this->mLocalFile;
}
/**
* @return UploadStashFile|null
*/
public function getStashFile() {
return $this->mStashFile;
}
/**
* Like stashFile(), but respects extensions' wishes to prevent the stashing. verifyUpload() must
* be called before calling this method (unless $isPartial is true).
*
* Upload stash exceptions are also caught and converted to an error status.
*
* @since 1.28
* @stable to override
* @param User $user
* @param bool $isPartial Pass `true` if this is a part of a chunked upload (not a complete file).
* @return Status If successful, value is an UploadStashFile instance
*/
public function tryStashFile( User $user, $isPartial = false ) {
if ( !$isPartial ) {
$error = $this->runUploadStashFileHook( $user );
if ( $error ) {
return Status::newFatal( ...$error );
}
}
try {
$file = $this->doStashFile( $user );
return Status::newGood( $file );
} catch ( UploadStashException $e ) {
return Status::newFatal( 'uploadstash-exception', get_class( $e ), $e->getMessage() );
}
}
/**
* @param User $user
* @return array|null Error message and parameters, null if there's no error
*/
protected function runUploadStashFileHook( User $user ) {
$props = $this->mFileProps;
$error = null;
$this->getHookRunner()->onUploadStashFile( $this, $user, $props, $error );
if ( $error && !is_array( $error ) ) {
$error = [ $error ];
}
return $error;
}
/**
* Implementation for stashFile() and tryStashFile().
*
* @stable to override
* @param User|null $user
* @return UploadStashFile Stashed file
*/
protected function doStashFile( User $user = null ) {
$stash = MediaWikiServices::getInstance()->getRepoGroup()
->getLocalRepo()->getUploadStash( $user );
$file = $stash->stashFile( $this->mTempPath, $this->getSourceType(), $this->mFileProps );
$this->mStashFile = $file;
return $file;
}
/**
* If we've modified the upload file, then we need to manually remove it
* on exit to clean up.
*/
public function cleanupTempFile() {
if ( $this->mRemoveTempFile && $this->tempFileObj ) {
// Delete when all relevant TempFSFile handles go out of scope
wfDebug( __METHOD__ . ": Marked temporary file '{$this->mTempPath}' for removal" );
$this->tempFileObj->autocollect();
}
}
/**
* @return string|null
*/
public function getTempPath() {
return $this->mTempPath;
}
/**
* Split a file into a base name and all dot-delimited 'extensions'
* on the end. Some web server configurations will fall back to
* earlier pseudo-'extensions' to determine type and execute
* scripts, so we need to check them all.
*
* @param string $filename
* @return array [ string, string[] ]
*/
public static function splitExtensions( $filename ) {
$bits = explode( '.', $filename );
$basename = array_shift( $bits );
return [ $basename, $bits ];
}
/**
* Perform case-insensitive match against a list of file extensions.
*
* @param string $ext File extension
* @param array $list
* @return bool Returns true if the extension is in the list.
*/
public static function checkFileExtension( $ext, $list ) {
return in_array( strtolower( $ext ?? '' ), $list, true );
}
/**
* Perform case-insensitive match against a list of file extensions.
* Returns an array of matching extensions.
*
* @param string[] $ext File extensions
* @param string[] $list
* @return string[]
*/
public static function checkFileExtensionList( $ext, $list ) {
return array_intersect( array_map( 'strtolower', $ext ), $list );
}
/**
* Checks if the MIME type of the uploaded file matches the file extension.
*
* @param string $mime The MIME type of the uploaded file
* @param string $extension The filename extension that the file is to be served with
* @return bool
*/
public static function verifyExtension( $mime, $extension ) {
$magic = MediaWikiServices::getInstance()->getMimeAnalyzer();
if ( !$mime || $mime === 'unknown' || $mime === 'unknown/unknown' ) {
if ( !$magic->isRecognizableExtension( $extension ) ) {
wfDebug( __METHOD__ . ": passing file with unknown detected mime type; " .
"unrecognized extension '$extension', can't verify" );
return true;
}
wfDebug( __METHOD__ . ": rejecting file with unknown detected mime type; " .
"recognized extension '$extension', so probably invalid file" );
return false;
}
$match = $magic->isMatchingExtension( $extension, $mime );
if ( $match === null ) {
if ( $magic->getMimeTypesFromExtension( $extension ) !== [] ) {
wfDebug( __METHOD__ . ": No extension known for $mime, but we know a mime for $extension" );
return false;
}
wfDebug( __METHOD__ . ": no file extension known for mime type $mime, passing file" );
return true;
}
if ( $match ) {
wfDebug( __METHOD__ . ": mime type $mime matches extension $extension, passing file" );
/** @todo If it's a bitmap, make sure PHP or ImageMagick resp. can handle it! */
return true;
}
wfDebug( __METHOD__
. ": mime type $mime mismatches file extension $extension, rejecting file" );
return false;
}
/**
* Heuristic for detecting files that *could* contain JavaScript instructions or
* things that may look like HTML to a browser and are thus
* potentially harmful. The present implementation will produce false
* positives in some situations.
*
* @param string|null $file Pathname to the temporary upload file
* @param string $mime The MIME type of the file
* @param string|null $extension The extension of the file
* @return bool True if the file contains something looking like embedded scripts
*/
public static function detectScript( $file, $mime, $extension ) {
# ugly hack: for text files, always look at the entire file.
# For binary field, just check the first K.
if ( str_starts_with( $mime ?? '', 'text/' ) ) {
$chunk = file_get_contents( $file );
} else {
$fp = fopen( $file, 'rb' );
if ( !$fp ) {
return false;
}
$chunk = fread( $fp, 1024 );
fclose( $fp );
}
$chunk = strtolower( $chunk );
if ( !$chunk ) {
return false;
}
# decode from UTF-16 if needed (could be used for obfuscation).
if ( str_starts_with( $chunk, "\xfe\xff" ) ) {
$enc = 'UTF-16BE';
} elseif ( str_starts_with( $chunk, "\xff\xfe" ) ) {
$enc = 'UTF-16LE';
} else {
$enc = null;
}
if ( $enc !== null ) {
$chunk = iconv( $enc, "ASCII//IGNORE", $chunk );
}
$chunk = trim( $chunk );
/** @todo FIXME: Convert from UTF-16 if necessary! */
wfDebug( __METHOD__ . ": checking for embedded scripts and HTML stuff" );
# check for HTML doctype
if ( preg_match( "/<!DOCTYPE *X?HTML/i", $chunk ) ) {
return true;
}
// Some browsers will interpret obscure xml encodings as UTF-8, while
// PHP/expat will interpret the given encoding in the xml declaration (T49304)
if ( $extension === 'svg' || str_starts_with( $mime ?? '', 'image/svg' ) ) {
if ( self::checkXMLEncodingMissmatch( $file ) ) {
return true;
}
}
// Quick check for HTML heuristics in old IE and Safari.
//
// The exact heuristics IE uses are checked separately via verifyMimeType(), so we
// don't need them all here as it can cause many false positives.
//
// Check for `<script` and such still to forbid script tags and embedded HTML in SVG:
$tags = [
'<body',
'<head',
'<html', # also in safari
'<script', # also in safari
];
foreach ( $tags as $tag ) {
if ( strpos( $chunk, $tag ) !== false ) {
wfDebug( __METHOD__ . ": found something that may make it be mistaken for html: $tag" );
return true;
}
}
/*
* look for JavaScript
*/
# resolve entity-refs to look at attributes. may be harsh on big files... cache result?
$chunk = Sanitizer::decodeCharReferences( $chunk );
# look for script-types
if ( preg_match( '!type\s*=\s*[\'"]?\s*(?:\w*/)?(?:ecma|java)!im', $chunk ) ) {
wfDebug( __METHOD__ . ": found script types" );
return true;
}
# look for html-style script-urls
if ( preg_match( '!(?:href|src|data)\s*=\s*[\'"]?\s*(?:ecma|java)script:!im', $chunk ) ) {
wfDebug( __METHOD__ . ": found html-style script urls" );
return true;
}
# look for css-style script-urls
if ( preg_match( '!url\s*\(\s*[\'"]?\s*(?:ecma|java)script:!im', $chunk ) ) {
wfDebug( __METHOD__ . ": found css-style script urls" );
return true;
}
wfDebug( __METHOD__ . ": no scripts found" );
return false;
}
/**
* Check an allowed list of xml encodings that are known not to be interpreted differently
* by the server's xml parser (expat) and some common browsers.
*
* @param string $file Pathname to the temporary upload file
* @return bool True if the file contains an encoding that could be misinterpreted
*/
public static function checkXMLEncodingMissmatch( $file ) {
// https://mimesniff.spec.whatwg.org/#resource-header says browsers
// should read the first 1445 bytes. Do 4096 bytes for good measure.
// XML Spec says XML declaration if present must be first thing in file
// other than BOM
$contents = file_get_contents( $file, false, null, 0, 4096 );
$encodingRegex = '!encoding[ \t\n\r]*=[ \t\n\r]*[\'"](.*?)[\'"]!si';
if ( preg_match( "!<\?xml\b(.*?)\?>!si", $contents, $matches ) ) {
if ( preg_match( $encodingRegex, $matches[1], $encMatch )
&& !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
) {
wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'" );
return true;
}
} elseif ( preg_match( "!<\?xml\b!i", $contents ) ) {
// Start of XML declaration without an end in the first 4096 bytes
// bytes. There shouldn't be a legitimate reason for this to happen.
wfDebug( __METHOD__ . ": Unmatched XML declaration start" );
return true;
} elseif ( str_starts_with( $contents, "\x4C\x6F\xA7\x94" ) ) {
// EBCDIC encoded XML
wfDebug( __METHOD__ . ": EBCDIC Encoded XML" );
return true;
}
// It's possible the file is encoded with multibyte encoding, so re-encode attempt to
// detect the encoding in case it specifies an encoding not allowed in self::$safeXmlEncodings
$attemptEncodings = [ 'UTF-16', 'UTF-16BE', 'UTF-32', 'UTF-32BE' ];
foreach ( $attemptEncodings as $encoding ) {
AtEase::suppressWarnings();
$str = iconv( $encoding, 'UTF-8', $contents );
AtEase::restoreWarnings();
if ( $str != '' && preg_match( "!<\?xml\b(.*?)\?>!si", $str, $matches ) ) {
if ( preg_match( $encodingRegex, $matches[1], $encMatch )
&& !in_array( strtoupper( $encMatch[1] ), self::$safeXmlEncodings )
) {
wfDebug( __METHOD__ . ": Found unsafe XML encoding '{$encMatch[1]}'" );
return true;
}
} elseif ( $str != '' && preg_match( "!<\?xml\b!i", $str ) ) {
// Start of XML declaration without an end in the first 4096 bytes
// bytes. There shouldn't be a legitimate reason for this to happen.
wfDebug( __METHOD__ . ": Unmatched XML declaration start" );
return true;
}
}
return false;
}
/**
* @param string $filename
* @param bool $partial
* @return bool|array
*/
protected function detectScriptInSvg( $filename, $partial ) {
$this->mSVGNSError = false;
$check = new XmlTypeCheck(
$filename,
[ $this, 'checkSvgScriptCallback' ],
true,
[
'processing_instruction_handler' => [ __CLASS__, 'checkSvgPICallback' ],
'external_dtd_handler' => [ __CLASS__, 'checkSvgExternalDTD' ],
]
);
if ( $check->wellFormed !== true ) {
// Invalid xml (T60553)
// But only when non-partial (T67724)
return $partial ? false : [ 'uploadinvalidxml' ];
}
if ( $check->filterMatch ) {
if ( $this->mSVGNSError ) {
return [ 'uploadscriptednamespace', $this->mSVGNSError ];
}
return $check->filterMatchType;
}
return false;
}
/**
* Callback to filter SVG Processing Instructions.
*
* @param string $target Processing instruction name
* @param string $data Processing instruction attribute and value
* @return bool|array
*/
public static function checkSvgPICallback( $target, $data ) {
// Don't allow external stylesheets (T59550)
if ( preg_match( '/xml-stylesheet/i', $target ) ) {
return [ 'upload-scripted-pi-callback' ];
}
return false;
}
/**
* Verify that DTD URLs referenced are only the standard DTDs.
*
* Browsers seem to ignore external DTDs.
*
* However, just to be on the safe side, only allow DTDs from the SVG standard.
*
* @param string $type PUBLIC or SYSTEM
* @param string $publicId The well-known public identifier for the dtd
* @param string $systemId The url for the external dtd
* @return bool|array
*/
public static function checkSvgExternalDTD( $type, $publicId, $systemId ) {
// This doesn't include the XHTML+MathML+SVG doctype since we don't
// allow XHTML anyway.
static $allowedDTDs = [
'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd',
'http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd',
'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-basic.dtd',
'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-tiny.dtd',
// https://phabricator.wikimedia.org/T168856
'http://www.w3.org/TR/2001/PR-SVG-20010719/DTD/svg10.dtd',
];
if ( $type !== 'PUBLIC'
|| !in_array( $systemId, $allowedDTDs )
|| !str_starts_with( $publicId, "-//W3C//" )
) {
return [ 'upload-scripted-dtd' ];
}
return false;
}
/**
* @todo Replace this with a allow list filter!
* @param string $element
* @param array $attribs
* @param string|null $data
* @return bool|array
*/
public function checkSvgScriptCallback( $element, $attribs, $data = null ) {
[ $namespace, $strippedElement ] = self::splitXmlNamespace( $element );
// We specifically don't include:
// http://www.w3.org/1999/xhtml (T62771)
static $validNamespaces = [
'',
'adobe:ns:meta/',
'http://creativecommons.org/ns#',
'http://inkscape.sourceforge.net/dtd/sodipodi-0.dtd',
'http://ns.adobe.com/adobeillustrator/10.0/',
'http://ns.adobe.com/adobesvgviewerextensions/3.0/',
'http://ns.adobe.com/extensibility/1.0/',
'http://ns.adobe.com/flows/1.0/',
'http://ns.adobe.com/illustrator/1.0/',
'http://ns.adobe.com/imagereplacement/1.0/',
'http://ns.adobe.com/pdf/1.3/',
'http://ns.adobe.com/photoshop/1.0/',
'http://ns.adobe.com/saveforweb/1.0/',
'http://ns.adobe.com/variables/1.0/',
'http://ns.adobe.com/xap/1.0/',
'http://ns.adobe.com/xap/1.0/g/',
'http://ns.adobe.com/xap/1.0/g/img/',
'http://ns.adobe.com/xap/1.0/mm/',
'http://ns.adobe.com/xap/1.0/rights/',
'http://ns.adobe.com/xap/1.0/stype/dimensions#',
'http://ns.adobe.com/xap/1.0/stype/font#',
'http://ns.adobe.com/xap/1.0/stype/manifestitem#',
'http://ns.adobe.com/xap/1.0/stype/resourceevent#',
'http://ns.adobe.com/xap/1.0/stype/resourceref#',
'http://ns.adobe.com/xap/1.0/t/pg/',
'http://purl.org/dc/elements/1.1/',
'http://purl.org/dc/elements/1.1',
'http://schemas.microsoft.com/visio/2003/svgextensions/',
'http://sodipodi.sourceforge.net/dtd/sodipodi-0.dtd',
'http://taptrix.com/inkpad/svg_extensions',
'http://web.resource.org/cc/',
'http://www.freesoftware.fsf.org/bkchem/cdml',
'http://www.inkscape.org/namespaces/inkscape',
'http://www.opengis.net/gml',
'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
'http://www.w3.org/2000/svg',
'http://www.w3.org/tr/rec-rdf-syntax/',
'http://www.w3.org/2000/01/rdf-schema#',
'http://www.w3.org/2000/02/svg/testsuite/description/', // https://phabricator.wikimedia.org/T278044
];
// Inkscape mangles namespace definitions created by Adobe Illustrator.
// This is nasty but harmless. (T144827)
$isBuggyInkscape = preg_match( '/^&(#38;)*ns_[a-z_]+;$/', $namespace );
if ( !( $isBuggyInkscape || in_array( $namespace, $validNamespaces ) ) ) {
wfDebug( __METHOD__ . ": Non-svg namespace '$namespace' in uploaded file." );
/** @todo Return a status object to a closure in XmlTypeCheck, for MW1.21+ */
$this->mSVGNSError = $namespace;
return true;
}
// check for elements that can contain javascript
if ( $strippedElement === 'script' ) {
wfDebug( __METHOD__ . ": Found script element '$element' in uploaded file." );
return [ 'uploaded-script-svg', $strippedElement ];
}
// 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>
if ( $strippedElement === 'handler' ) {
wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file." );
return [ 'uploaded-script-svg', $strippedElement ];
}
// SVG reported in Feb '12 that used xml:stylesheet to generate javascript block
if ( $strippedElement === 'stylesheet' ) {
wfDebug( __METHOD__ . ": Found scriptable element '$element' in uploaded file." );
return [ 'uploaded-script-svg', $strippedElement ];
}
// Block iframes, in case they pass the namespace check
if ( $strippedElement === 'iframe' ) {
wfDebug( __METHOD__ . ": iframe in uploaded file." );
return [ 'uploaded-script-svg', $strippedElement ];
}
// Check <style> css
if ( $strippedElement === 'style'
&& self::checkCssFragment( Sanitizer::normalizeCss( $data ) )
) {
wfDebug( __METHOD__ . ": hostile css in style element." );
return [ 'uploaded-hostile-svg' ];
}
static $cssAttrs = [ 'font', 'clip-path', 'fill', 'filter', 'marker',
'marker-end', 'marker-mid', 'marker-start', 'mask', 'stroke' ];
foreach ( $attribs as $attrib => $value ) {
// If attributeNamespace is '', it is relative to its element's namespace
[ $attributeNamespace, $stripped ] = self::splitXmlNamespace( $attrib );
$value = strtolower( $value );
if ( !(
// Inkscape element's have valid attribs that start with on and are safe, fail all others
$namespace === 'http://www.inkscape.org/namespaces/inkscape' &&
$attributeNamespace === ''
) && str_starts_with( $stripped, 'on' )
) {
wfDebug( __METHOD__
. ": Found event-handler attribute '$attrib'='$value' in uploaded file." );
return [ 'uploaded-event-handler-on-svg', $attrib, $value ];
}
// Do not allow relative links, or unsafe url schemas.
// For <a> tags, only data:, http: and https: and same-document
// fragment links are allowed.
// For all other tags, only 'data:' and fragments (#) are allowed.
if (
$stripped === 'href'
&& $value !== ''
&& !str_starts_with( $value, 'data:' )
&& !str_starts_with( $value, '#' )
&& !( $strippedElement === 'a' && preg_match( '!^https?://!i', $value ) )
) {
wfDebug( __METHOD__ . ": Found href attribute <$strippedElement "
. "'$attrib'='$value' in uploaded file." );
return [ 'uploaded-href-attribute-svg', $strippedElement, $attrib, $value ];
}
// Only allow 'data:\' targets that should be safe.
// This prevents vectors like image/svg, text/xml, application/xml, and text/html, which can contain scripts
if ( $stripped === 'href' && strncasecmp( 'data:', $value, 5 ) === 0 ) {
// RFC2397 parameters.
// This is only slightly slower than (;[\w;]+)*.
// phpcs:ignore Generic.Files.LineLength
$parameters = '(?>;[a-zA-Z0-9\!#$&\'*+.^_`{|}~-]+=(?>[a-zA-Z0-9\!#$&\'*+.^_`{|}~-]+|"(?>[\0-\x0c\x0e-\x21\x23-\x5b\x5d-\x7f]+|\\\\[\0-\x7f])*"))*(?:;base64)?';
if ( !preg_match( "!^data:\s*image/(gif|jpeg|jpg|png)$parameters,!i", $value ) ) {
wfDebug( __METHOD__ . ": Found href to allow listed data: uri "
. "\"<$strippedElement '$attrib'='$value'...\" in uploaded file." );
return [ 'uploaded-href-unsafe-target-svg', $strippedElement, $attrib, $value ];
}
}
// Change href with animate from (http://html5sec.org/#137).
if ( $stripped === 'attributename'
&& $strippedElement === 'animate'
&& $this->stripXmlNamespace( $value ) === 'href'
) {
wfDebug( __METHOD__ . ": Found animate that might be changing href using from "
. "\"<$strippedElement '$attrib'='$value'...\" in uploaded file." );
return [ 'uploaded-animate-svg', $strippedElement, $attrib, $value ];
}
// Use set/animate to add event-handler attribute to parent.
if ( ( $strippedElement === 'set' || $strippedElement === 'animate' )
&& $stripped === 'attributename'
&& str_starts_with( $value, 'on' )
) {
wfDebug( __METHOD__ . ": Found svg setting event-handler attribute with "
. "\"<$strippedElement $stripped='$value'...\" in uploaded file." );
return [ 'uploaded-setting-event-handler-svg', $strippedElement, $stripped, $value ];
}
// use set to add href attribute to parent element.
if ( $strippedElement === 'set'
&& $stripped === 'attributename'
&& str_contains( $value, 'href' )
) {
wfDebug( __METHOD__ . ": Found svg setting href attribute '$value' in uploaded file." );
return [ 'uploaded-setting-href-svg' ];
}
// use set to add a remote / data / script target to an element.
if ( $strippedElement === 'set'
&& $stripped === 'to'
&& preg_match( '!(http|https|data|script):!im', $value )
) {
wfDebug( __METHOD__ . ": Found svg setting attribute to '$value' in uploaded file." );
return [ 'uploaded-wrong-setting-svg', $value ];
}
// use handler attribute with remote / data / script.
if ( $stripped === 'handler' && preg_match( '!(http|https|data|script):!im', $value ) ) {
wfDebug( __METHOD__ . ": Found svg setting handler with remote/data/script "
. "'$attrib'='$value' in uploaded file." );
return [ 'uploaded-setting-handler-svg', $attrib, $value ];
}
// use CSS styles to bring in remote code.
if ( $stripped === 'style'
&& self::checkCssFragment( Sanitizer::normalizeCss( $value ) )
) {
wfDebug( __METHOD__ . ": Found svg setting a style with "
. "remote url '$attrib'='$value' in uploaded file." );
return [ 'uploaded-remote-url-svg', $attrib, $value ];
}
// Several attributes can include css, css character escaping isn't allowed.
if ( in_array( $stripped, $cssAttrs, true )
&& self::checkCssFragment( $value )
) {
wfDebug( __METHOD__ . ": Found svg setting a style with "
. "remote url '$attrib'='$value' in uploaded file." );
return [ 'uploaded-remote-url-svg', $attrib, $value ];
}
// image filters can pull in url, which could be svg that executes scripts.
// Only allow url( "#foo" ).
// Do not allow url( http://example.com )
if ( $strippedElement === 'image'
&& $stripped === 'filter'
&& preg_match( '!url\s*\(\s*["\']?[^#]!im', $value )
) {
wfDebug( __METHOD__ . ": Found image filter with url: "
. "\"<$strippedElement $stripped='$value'...\" in uploaded file." );
return [ 'uploaded-image-filter-svg', $strippedElement, $stripped, $value ];
}
}
return false; // No scripts detected
}
/**
* Check a block of CSS or CSS fragment for anything that looks like
* it is bringing in remote code.
* @param string $value a string of CSS
* @return bool true if the CSS contains an illegal string, false if otherwise
*/
private static function checkCssFragment( $value ) {
# Forbid external stylesheets, for both reliability and to protect viewer's privacy
if ( stripos( $value, '@import' ) !== false ) {
return true;
}
# We allow @font-face to embed fonts with data: urls, so we snip the string
# 'url' out so that this case won't match when we check for urls below
$pattern = '!(@font-face\s*{[^}]*src:)url(\("data:;base64,)!im';
$value = preg_replace( $pattern, '$1$2', $value );
# Check for remote and executable CSS. Unlike in Sanitizer::checkCss, the CSS
# properties filter and accelerator don't seem to be useful for xss in SVG files.
# Expression and -o-link don't seem to work either, but filtering them here in case.
# Additionally, we catch remote urls like url("http:..., url('http:..., url(http:...,
# but not local ones such as url("#..., url('#..., url(#....
if ( preg_match( '!expression
| -o-link\s*:
| -o-link-source\s*:
| -o-replace\s*:!imx', $value ) ) {
return true;
}
if ( preg_match_all(
"!(\s*(url|image|image-set)\s*\(\s*[\"']?\s*[^#]+.*?\))!sim",
$value,
$matches
) !== 0
) {
# TODO: redo this in one regex. Until then, url("#whatever") matches the first
foreach ( $matches[1] as $match ) {
if ( !preg_match( "!\s*(url|image|image-set)\s*\(\s*(#|'#|\"#)!im", $match ) ) {
return true;
}
}
}
if ( preg_match( '/[\000-\010\013\016-\037\177]/', $value ) ) {
return true;
}
return false;
}
/**
* Divide the element name passed by the XML parser to the callback into URI and prefix.
* @param string $element
* @return array Containing the namespace URI and prefix
*/
private static function splitXmlNamespace( $element ) {
// 'http://www.w3.org/2000/svg:script' -> [ 'http://www.w3.org/2000/svg', 'script' ]
$parts = explode( ':', strtolower( $element ) );
$name = array_pop( $parts );
$ns = implode( ':', $parts );
return [ $ns, $name ];
}
/**
* @param string $element
* @return string
*/
private function stripXmlNamespace( $element ) {
// 'http://www.w3.org/2000/svg:script' -> 'script'
return self::splitXmlNamespace( $element )[1];
}
/**
* Generic wrapper function for a virus scanner program.
* This relies on the $wgAntivirus and $wgAntivirusSetup variables.
* $wgAntivirusRequired may be used to deny upload if the scan fails.
*
* @param string $file Pathname to the temporary upload file
* @return bool|null|string False if not virus is found, null if the scan fails or is disabled,
* or a string containing feedback from the virus scanner if a virus was found.
* If textual feedback is missing but a virus was found, this function returns true.
*/
public static function detectVirus( $file ) {
global $wgOut;
$mainConfig = MediaWikiServices::getInstance()->getMainConfig();
$antivirus = $mainConfig->get( MainConfigNames::Antivirus );
$antivirusSetup = $mainConfig->get( MainConfigNames::AntivirusSetup );
$antivirusRequired = $mainConfig->get( MainConfigNames::AntivirusRequired );
if ( !$antivirus ) {
wfDebug( __METHOD__ . ": virus scanner disabled" );
return null;
}
if ( !$antivirusSetup[$antivirus] ) {
wfDebug( __METHOD__ . ": unknown virus scanner: {$antivirus}" );
$wgOut->wrapWikiMsg( "<div class=\"error\">\n$1\n</div>",
[ 'virus-badscanner', $antivirus ] );
return wfMessage( 'virus-unknownscanner' )->text() . " {$antivirus}";
}
# look up scanner configuration
$command = $antivirusSetup[$antivirus]['command'];
$exitCodeMap = $antivirusSetup[$antivirus]['codemap'];
$msgPattern = $antivirusSetup[$antivirus]['messagepattern'] ?? null;
if ( !str_contains( $command, "%f" ) ) {
# simple pattern: append file to scan
$command .= " " . Shell::escape( $file );
} else {
# complex pattern: replace "%f" with file to scan
$command = str_replace( "%f", Shell::escape( $file ), $command );
}
wfDebug( __METHOD__ . ": running virus scan: $command " );
# execute virus scanner
$exitCode = false;
# NOTE: there's a 50-line workaround to make stderr redirection work on windows, too.
# that does not seem to be worth the pain.
# Ask me (Duesentrieb) about it if it's ever needed.
$output = wfShellExecWithStderr( $command, $exitCode );
# map exit code to AV_xxx constants.
$mappedCode = $exitCode;
if ( $exitCodeMap ) {
if ( isset( $exitCodeMap[$exitCode] ) ) {
$mappedCode = $exitCodeMap[$exitCode];
} elseif ( isset( $exitCodeMap["*"] ) ) {
$mappedCode = $exitCodeMap["*"];
}
}
# NB: AV_NO_VIRUS is 0, but AV_SCAN_FAILED is false,
# so we need the strict equalities === and thus can't use a switch here
if ( $mappedCode === AV_SCAN_FAILED ) {
# scan failed (code was mapped to false by $exitCodeMap)
wfDebug( __METHOD__ . ": failed to scan $file (code $exitCode)." );
$output = $antivirusRequired
? wfMessage( 'virus-scanfailed', [ $exitCode ] )->text()
: null;
} elseif ( $mappedCode === AV_SCAN_ABORTED ) {
# scan failed because filetype is unknown (probably immune)
wfDebug( __METHOD__ . ": unsupported file type $file (code $exitCode)." );
$output = null;
} elseif ( $mappedCode === AV_NO_VIRUS ) {
# no virus found
wfDebug( __METHOD__ . ": file passed virus scan." );
$output = false;
} else {
$output = trim( $output );
if ( !$output ) {
$output = true; # if there's no output, return true
} elseif ( $msgPattern ) {
$groups = [];
if ( preg_match( $msgPattern, $output, $groups ) && $groups[1] ) {
$output = $groups[1];
}
}
wfDebug( __METHOD__ . ": FOUND VIRUS! scanner feedback: $output" );
}
return $output;
}
/**
* Check if there's a file overwrite conflict and, if so, if restrictions
* forbid this user from performing the upload.
*
* @param Authority $performer
*
* @return bool|array
*/
private function checkOverwrite( Authority $performer ) {
// First check whether the local file can be overwritten
$file = $this->getLocalFile();
$file->load( IDBAccessObject::READ_LATEST );
if ( $file->exists() ) {
if ( !self::userCanReUpload( $performer, $file ) ) {
return [ 'fileexists-forbidden', $file->getName() ];
}
return true;
}
$services = MediaWikiServices::getInstance();
/* Check shared conflicts: if the local file does not exist, but
* RepoGroup::findFile finds a file, it exists in a shared repository.
*/
$file = $services->getRepoGroup()->findFile( $this->getTitle(), [ 'latest' => true ] );
if ( $file && !$performer->isAllowed( 'reupload-shared' ) ) {
return [ 'fileexists-shared-forbidden', $file->getName() ];
}
return true;
}
/**
* Check if a user is the last uploader
*
* @param Authority $performer
* @param File $img
* @return bool
*/
public static function userCanReUpload( Authority $performer, File $img ) {
if ( $performer->isAllowed( 'reupload' ) ) {
return true; // non-conditional
}
if ( !$performer->isAllowed( 'reupload-own' ) ) {
return false;
}
if ( !( $img instanceof LocalFile ) ) {
return false;
}
return $performer->getUser()->equals( $img->getUploader( File::RAW ) );
}
/**
* Helper function that does various existence checks for a file.
* The following checks are performed:
* - If the file exists
* - If an article with the same name as the file exists
* - If a file exists with normalized extension
* - If the file looks like a thumbnail and the original exists
*
* @param File $file The File object to check
* @return array|false False if the file does not exist, else an array
*/
public static function getExistsWarning( $file ) {
if ( $file->exists() ) {
return [ 'warning' => 'exists', 'file' => $file ];
}
if ( $file->getTitle()->getArticleID() ) {
return [ 'warning' => 'page-exists', 'file' => $file ];
}
$n = strrpos( $file->getName(), '.' );
if ( $n > 0 ) {
$partname = substr( $file->getName(), 0, $n );
$extension = substr( $file->getName(), $n + 1 );
} else {
$partname = $file->getName();
$extension = '';
}
$normalizedExtension = File::normalizeExtension( $extension );
$localRepo = MediaWikiServices::getInstance()->getRepoGroup()->getLocalRepo();
if ( $normalizedExtension != $extension ) {
// We're not using the normalized form of the extension.
// Normal form is lowercase, using most common of alternate
// extensions (e.g. 'jpg' rather than 'JPEG').
// Check for another file using the normalized form...
$nt_lc = Title::makeTitle( NS_FILE, "{$partname}.{$normalizedExtension}" );
$file_lc = $localRepo->newFile( $nt_lc );
if ( $file_lc->exists() ) {
return [
'warning' => 'exists-normalized',
'file' => $file,
'normalizedFile' => $file_lc
];
}
}
// Check for files with the same name but a different extension
$similarFiles = $localRepo->findFilesByPrefix( "{$partname}.", 1 );
if ( count( $similarFiles ) ) {
return [
'warning' => 'exists-normalized',
'file' => $file,
'normalizedFile' => $similarFiles[0],
];
}
if ( self::isThumbName( $file->getName() ) ) {
// Check for filenames like 50px- or 180px-, these are mostly thumbnails
$nt_thb = Title::newFromText(
substr( $partname, strpos( $partname, '-' ) + 1 ) . '.' . $extension,
NS_FILE
);
$file_thb = $localRepo->newFile( $nt_thb );
if ( $file_thb->exists() ) {
return [
'warning' => 'thumb',
'file' => $file,
'thumbFile' => $file_thb
];
}
// The file does not exist, but we just don't like the name
return [
'warning' => 'thumb-name',
'file' => $file,
'thumbFile' => $file_thb
];
}
foreach ( self::getFilenamePrefixBlacklist() as $prefix ) {
if ( str_starts_with( $partname, $prefix ) ) {
return [
'warning' => 'bad-prefix',
'file' => $file,
'prefix' => $prefix
];
}
}
return false;
}
/**
* Helper function that checks whether the filename looks like a thumbnail
* @param string $filename
* @return bool
*/
public static function isThumbName( $filename ) {
$n = strrpos( $filename, '.' );
$partname = $n ? substr( $filename, 0, $n ) : $filename;
return (
substr( $partname, 3, 3 ) === 'px-' ||
substr( $partname, 2, 3 ) === 'px-'
) && preg_match( "/[0-9]{2}/", substr( $partname, 0, 2 ) );
}
/**
* Get a list of disallowed filename prefixes from [[MediaWiki:Filename-prefix-blacklist]]
*
* @return string[] List of prefixes
*/
public static function getFilenamePrefixBlacklist() {
$list = [];
$message = wfMessage( 'filename-prefix-blacklist' )->inContentLanguage();
if ( !$message->isDisabled() ) {
$lines = explode( "\n", $message->plain() );
foreach ( $lines as $line ) {
// Remove comment lines
$comment = substr( trim( $line ), 0, 1 );
if ( $comment === '#' || $comment == '' ) {
continue;
}
// Remove additional comments after a prefix
$comment = strpos( $line, '#' );
if ( $comment > 0 ) {
$line = substr( $line, 0, $comment - 1 );
}
$list[] = trim( $line );
}
}
return $list;
}
/**
* Gets image info about the file just uploaded.
*
* @deprecated since 1.42, subclasses of ApiUpload can use
* ApiUpload::getUploadImageInfo() instead.
*
* @param ?ApiResult $result unused since 1.42
* @return array Image info
*/
public function getImageInfo( $result = null ) {
$apiUpload = ApiUpload::getDummyInstance();
return $apiUpload->getUploadImageInfo( $this );
}
/**
* @param array $error
* @return Status
*/
public function convertVerifyErrorToStatus( $error ) {
$code = $error['status'];
unset( $code['status'] );
return Status::newFatal( $this->getVerificationErrorCode( $code ), $error );
}
/**
* Get MediaWiki's maximum uploaded file size for a given type of upload, based on
* $wgMaxUploadSize.
*
* @param null|string $forType
* @return int
*/
public static function getMaxUploadSize( $forType = null ) {
$maxUploadSize = MediaWikiServices::getInstance()->getMainConfig()->get( MainConfigNames::MaxUploadSize );
if ( is_array( $maxUploadSize ) ) {
if ( $forType !== null && isset( $maxUploadSize[$forType] ) ) {
return $maxUploadSize[$forType];
}
return $maxUploadSize['*'];
}
return intval( $maxUploadSize );
}
/**
* Get the PHP maximum uploaded file size, based on ini settings. If there is no limit or the
* limit can't be guessed, return a very large number (PHP_INT_MAX) instead.
*
* @since 1.27
* @return int
*/
public static function getMaxPhpUploadSize() {
$phpMaxFileSize = wfShorthandToInteger(
ini_get( 'upload_max_filesize' ),
PHP_INT_MAX
);
$phpMaxPostSize = wfShorthandToInteger(
ini_get( 'post_max_size' ),
PHP_INT_MAX
) ?: PHP_INT_MAX;
return min( $phpMaxFileSize, $phpMaxPostSize );
}
/**
* Get the current status of a chunked upload (used for polling).
*
* This should only be called during POST requests since we
* fetch from dc-local MainStash, and from a GET request we can't
* know that the value is available or up-to-date.
*
* @param UserIdentity $user
* @param string $statusKey
* @return mixed[]|false
*/
public static function getSessionStatus( UserIdentity $user, $statusKey ) {
$store = self::getUploadSessionStore();
$key = self::getUploadSessionKey( $store, $user, $statusKey );
return $store->get( $key );
}
/**
* Set the current status of a chunked upload (used for polling).
*
* The value will be set in cache for 1 day.
*
* This should only be called during POST requests.
*
* @param UserIdentity $user
* @param string $statusKey
* @param array|false $value
* @return void
*/
public static function setSessionStatus( UserIdentity $user, $statusKey, $value ) {
$store = self::getUploadSessionStore();
$key = self::getUploadSessionKey( $store, $user, $statusKey );
$logger = LoggerFactory::getInstance( 'upload' );
if ( is_array( $value ) && ( $value['result'] ?? '' ) === 'Failure' ) {
$logger->info( 'Upload session {key} for {user} set to failure {status} at {stage}',
[
'result' => $value['result'] ?? '',
'stage' => $value['stage'] ?? 'unknown',
'user' => $user->getName(),
'status' => (string)( $value['status'] ?? '-' ),
'filekey' => $value['filekey'] ?? '',
'key' => $statusKey
]
);
} elseif ( is_array( $value ) ) {
$logger->debug( 'Upload session {key} for {user} changed {status} at {stage}',
[
'result' => $value['result'] ?? '',
'stage' => $value['stage'] ?? 'unknown',
'user' => $user->getName(),
'status' => (string)( $value['status'] ?? '-' ),
'filekey' => $value['filekey'] ?? '',
'key' => $statusKey
]
);
} else {
$logger->debug( "Upload session {key} deleted for {user}",
[
'value' => $value,
'key' => $statusKey,
'user' => $user->getName()
]
);
}
if ( $value === false ) {
$store->delete( $key );
} else {
$store->set( $key, $value, $store::TTL_DAY );
}
}
/**
* @param BagOStuff $store
* @param UserIdentity $user
* @param string $statusKey
* @return string
*/
private static function getUploadSessionKey( BagOStuff $store, UserIdentity $user, $statusKey ) {
return $store->makeKey(
'uploadstatus',
$user->isRegistered() ? $user->getId() : md5( $user->getName() ),
$statusKey
);
}
/**
* @return BagOStuff
*/
private static function getUploadSessionStore() {
return MediaWikiServices::getInstance()->getMainObjectStash();
}
}