FileExtensionFilter.php

Go to the documentation of this file.

<?php
 
declare(strict_types=1);
 
/*
 * This file is part of the TYPO3 CMS project.
 *
 * It is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, either version 2
 * of the License, or any later version.
 *
 * For the full copyright and license information, please read the
 * LICENSE.txt file that was distributed with this source code.
 *
 * The TYPO3 project - inspiring people to share!
 */
 
namespace ‪TYPO3\CMS\Core\Resource\Filter;
 
use ‪TYPO3\CMS\Backend\RecordList\DatabaseRecordList;
use ‪TYPO3\CMS\Core\DataHandling\DataHandler;
use TYPO3\CMS\Core\Resource\Driver\DriverInterface;
use ‪TYPO3\CMS\Core\Resource\Exception\ResourceDoesNotExistException;
use ‪TYPO3\CMS\Core\Resource\ResourceFactory;
use ‪TYPO3\CMS\Core\Utility\GeneralUtility;
 
class ‪FileExtensionFilter
{
    protected ?array ‪$allowedFileExtensions = null;
 
    protected ?array ‪$disallowedFileExtensions = null;
 
    public function ‪filter(
        array $references,
        string ‪$allowedFileExtensions,
        string ‪$disallowedFileExtensions,
        ‪DataHandler|‪DatabaseRecordList $dataHandler
    ): array {
        if (‪$allowedFileExtensions !== '') {
            $this->‪setAllowedFileExtensions($allowedFileExtensions);
        }
        if (‪$disallowedFileExtensions !== '') {
            $this->‪setDisallowedFileExtensions($disallowedFileExtensions);
        }
 
        $cleanReferences = [];
        foreach ($references as $reference) {
            if (empty($reference)) {
                continue;
            }
            $parts = GeneralUtility::revExplode('_', (string)$reference, 2);
            $fileReferenceUid = $parts[count($parts) - 1];
            try {
                $fileReference = GeneralUtility::makeInstance(ResourceFactory::class)->getFileReferenceObject($fileReferenceUid);
                $file = $fileReference->getOriginalFile();
                if ($this->‪isAllowed($file->getExtension())) {
                    $cleanReferences[] = $reference;
                } else {
                    // Remove the erroneously created reference record again
                    $dataHandler->deleteAction('sys_file_reference', $fileReferenceUid);
                }
            } catch (‪ResourceDoesNotExistException $e) {
                // do nothing
            }
        }
        return $cleanReferences;
    }
 
    public function ‪filterFileList($itemName, $itemIdentifier, $parentIdentifier, array $additionalInformation, DriverInterface $driver)
    {
        $returnCode = true;
        // Early return in case no file filters are set at all
        if ($this->allowedFileExtensions === null && $this->disallowedFileExtensions === null) {
            return $returnCode;
        }
        // Check that this is a file and not a folder
        if ($driver->fileExists($itemIdentifier)) {
            try {
                $fileInfo = $driver->getFileInfoByIdentifier($itemIdentifier, ['extension']);
            } catch (\InvalidArgumentException $e) {
                $fileInfo = [];
            }
            if (!$this->‪isAllowed((string)($fileInfo['extension'] ?? ''))) {
                $returnCode = -1;
            }
        }
        return $returnCode;
    }
 
    public function ‪isAllowed(string $fileExtension): bool
    {
        $fileExtension = strtolower($fileExtension);
        $result = true;
        // Check allowed file extensions
        if (!empty($this->allowedFileExtensions) && !in_array($fileExtension, $this->allowedFileExtensions, true)) {
            $result = false;
        }
        // Check disallowed file extensions
        if (!empty($this->disallowedFileExtensions) && in_array($fileExtension, $this->disallowedFileExtensions, true)) {
            $result = false;
        }
        return $result;
    }
 
    public function ‪setAllowedFileExtensions(mixed ‪$allowedFileExtensions): void
    {
        $this->allowedFileExtensions = $this->‪convertToLowercaseArray($allowedFileExtensions);
    }
 
    public function ‪getAllowedFileExtensions(): ?array
    {
        return ‪$this->allowedFileExtensions;
    }
 
    public function ‪setDisallowedFileExtensions(mixed ‪$disallowedFileExtensions): void
    {
        $this->disallowedFileExtensions = $this->‪convertToLowercaseArray($disallowedFileExtensions);
    }
 
    public function ‪getDisallowedFileExtensions(): ?array
    {
        return ‪$this->disallowedFileExtensions;
    }
 
    public function ‪getFilteredFileExtensions(): array
    {
        if ($this->disallowedFileExtensions === null) {
            return ['allowedFileExtensions' => $this->allowedFileExtensions ?? ['*']];
        }
 
        if ($this->allowedFileExtensions === null) {
            return ['disallowedFileExtensions' => ‪$this->disallowedFileExtensions];
        }
 
        return ['allowedFileExtensions' => array_filter($this->allowedFileExtensions, function ($fileExtension) {
            return !in_array($fileExtension, $this->disallowedFileExtensions, true);
        })];
    }
 
    protected function ‪convertToLowercaseArray(mixed $inputArgument): ?array
    {
        $returnValue = null;
        if (is_array($inputArgument)) {
            $returnValue = $inputArgument;
        } elseif ((string)$inputArgument !== '') {
            $returnValue = GeneralUtility::trimExplode(',', $inputArgument);
        }
 
        if (is_array($returnValue)) {
            $returnValue = array_map('strtolower', $returnValue);
        }
 
        return $returnValue;
    }
}