diff --git a/core/modules/file/file.module b/core/modules/file/file.module
index 0e5c0b31868d37e3dc8ee02e8f2a6bd9b5d5755b..925facef01b9c9bf8fced308bddfea803f39f266 100644
--- a/core/modules/file/file.module
+++ b/core/modules/file/file.module
@@ -25,6 +25,8 @@
use Drupal\Core\Template\Attribute;
use Symfony\Component\Mime\MimeTypeGuesserInterface;
+// cspell:ignore btxt
+
/**
* The regex pattern used when checking for insecure file types.
*/
@@ -1000,10 +1002,11 @@ function _file_save_upload_single(\SplFileInfo $file_info, $form_field_name, $va
// rename filename.php.foo and filename.php to filename.php_.foo_.txt and
// filename.php_.txt, respectively).
if (preg_match(FILE_INSECURE_EXTENSION_REGEX, $file->getFilename())) {
- // If the file will be rejected anyway due to a disallowed extension, it
- // should not be renamed; rather, we'll let file_validate_extensions()
- // reject it below.
- if (!isset($validators['file_validate_extensions']) || empty(file_validate_extensions($file, $extensions))) {
+ // If there is no file extension validation at all, or .txt is considered
+ // a valid extension and the file would otherwise pass validation, rename
+ // it. If the file will be rejected due to extension validation, it should
+ // not be renamed; rather, let file_validate_extensions() reject it below.
+ if (!isset($validators['file_validate_extensions']) || (preg_match('/\btxt\b/', $extensions) && empty(file_validate_extensions($file, $extensions)))) {
$file->setMimeType('text/plain');
$filename = $file->getFilename();
if (substr($filename, -4) != '.txt') {
@@ -1012,11 +1015,6 @@ function _file_save_upload_single(\SplFileInfo $file_info, $form_field_name, $va
}
$file->setFilename(file_munge_filename($filename, $extensions));
\Drupal::messenger()->addStatus(t('For security reasons, your upload has been renamed to %filename.', ['%filename' => $file->getFilename()]));
- // The .txt extension may not be in the allowed list of extensions. We
- // have to add it here or else the file upload will fail.
- if (!empty($validators['file_validate_extensions'][0])) {
- $validators['file_validate_extensions'][0] .= ' txt';
- }
}
}
}
diff --git a/core/modules/file/file.post_update.php b/core/modules/file/file.post_update.php
new file mode 100644
index 0000000000000000000000000000000000000000..707bb4e6b2e6d94427d5aed948fada434592aa88
--- /dev/null
+++ b/core/modules/file/file.post_update.php
@@ -0,0 +1,41 @@
+<?php
+
+/**
+ * @file
+ * Post update functions for File.
+ */
+
+use Drupal\Core\Config\Entity\ConfigEntityUpdater;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\file\Plugin\Field\FieldType\FileItem;
+
+/**
+ * Add txt to allowed extensions for all fields that allow uploads of insecure files.
+ */
+function file_post_update_add_txt_if_allows_insecure_extensions(&$sandbox = NULL) {
+ if (\Drupal::config('system.file')->get('allow_insecure_uploads')) {
+ return t('The system is configured to allow insecure file uploads. No file field updates are necessary.');
+ }
+
+ $updater = function (FieldConfig $field) {
+ // Determine if this field uses an item definition that extends FileItem.
+ if (is_subclass_of($field->getItemDefinition()->getClass(), FileItem::class)) {
+ $allowed_extensions_string = trim($field->getSetting('file_extensions'));
+ $allowed_extensions = array_filter(explode(' ', $allowed_extensions_string));
+ if (in_array('txt', $allowed_extensions, TRUE)) {
+ // Since .txt is specifically allowed, there's nothing to do.
+ return FALSE;
+ }
+ foreach ($allowed_extensions as $extension) {
+ // Allow .txt if an insecure extension is allowed.
+ if (preg_match(FILE_INSECURE_EXTENSION_REGEX, 'test.' . $extension)) {
+ $allowed_extensions_string .= ' txt';
+ $field->setSetting('file_extensions', $allowed_extensions_string);
+ return TRUE;
+ }
+ }
+ return FALSE;
+ }
+ };
+ \Drupal::classResolver(ConfigEntityUpdater::class)->update($sandbox, 'field_config', $updater);
+}
diff --git a/core/modules/file/src/Plugin/Field/FieldType/FileItem.php b/core/modules/file/src/Plugin/Field/FieldType/FileItem.php
index 41b30e9216cc9571a3564160354d5635be27242c..1f77571c0312cc098acea752e34455a46e56c803 100644
--- a/core/modules/file/src/Plugin/Field/FieldType/FileItem.php
+++ b/core/modules/file/src/Plugin/Field/FieldType/FileItem.php
@@ -225,14 +225,25 @@ public static function validateDirectory($element, FormStateInterface $form_stat
public static function validateExtensions($element, FormStateInterface $form_state) {
if (!empty($element['#value'])) {
$extensions = preg_replace('/([, ]+\.?)/', ' ', trim(strtolower($element['#value'])));
- $extensions = array_filter(explode(' ', $extensions));
- $extensions = implode(' ', array_unique($extensions));
+ $extension_array = array_unique(array_filter(explode(' ', $extensions)));
+ $extensions = implode(' ', $extension_array);
if (!preg_match('/^([a-z0-9]+([.][a-z0-9])* ?)+$/', $extensions)) {
$form_state->setError($element, t('The list of allowed extensions is not valid, be sure to exclude leading dots and to separate extensions with a comma or space.'));
}
else {
$form_state->setValueForElement($element, $extensions);
}
+
+ // If insecure uploads are not allowed and txt is not in the list of
+ // allowed extensions, ensure that no insecure extensions are allowed.
+ if (!in_array('txt', $extension_array, TRUE) && !\Drupal::config('system.file')->get('allow_insecure_uploads')) {
+ foreach ($extension_array as $extension) {
+ if (preg_match(FILE_INSECURE_EXTENSION_REGEX, 'test.' . $extension)) {
+ $form_state->setError($element, t('Add %txt_extension to the list of allowed extensions to securely upload files with a %extension extension. The %txt_extension extension will then be added automatically.', ['%extension' => $extension, '%txt_extension' => 'txt']));
+ break;
+ }
+ }
+ }
}
}
diff --git a/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php b/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
index 3c7180a0b03bb7a48fefa094959d9967b86bd443..399d55f2a78316cea7b652b7a291677a2d0718ad 100644
--- a/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
+++ b/core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
@@ -32,6 +32,8 @@
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpKernel\Exception\HttpException;
+// cspell:ignore btxt
+
/**
* File upload resource.
*
@@ -485,24 +487,24 @@ protected function prepareFilename($filename, array &$validators) {
// If the file will be rejected anyway due to a disallowed extension, it
// should not be renamed; rather, we'll let file_validate_extensions()
// reject it below.
- $passes_validation = FALSE;
if (!empty($validators['file_validate_extensions'][0])) {
$file = File::create([]);
$file->setFilename($filename);
$passes_validation = empty(file_validate_extensions($file, $validators['file_validate_extensions'][0]));
+ // Only allow upload and rename to .txt if .txt files are allowed.
+ $passes_validation = $passes_validation && preg_match('/\btxt\b/', $validators['file_validate_extensions'][0]);
+ }
+ else {
+ // All file extensions are allowed.
+ $passes_validation = TRUE;
}
- if (empty($validators['file_validate_extensions'][0]) || $passes_validation) {
+
+ if ($passes_validation) {
if ((substr($filename, -4) != '.txt')) {
// The destination filename will also later be used to create the URI.
$filename .= '.txt';
}
$filename = file_munge_filename($filename, $validators['file_validate_extensions'][0] ?? '');
-
- // The .txt extension may not be in the allowed list of extensions. We
- // have to add it here or else the file upload will fail.
- if (!empty($validators['file_validate_extensions'][0])) {
- $validators['file_validate_extensions'][0] .= ' txt';
- }
}
}
}
diff --git a/core/modules/file/tests/src/Functional/FileFieldWidgetTest.php b/core/modules/file/tests/src/Functional/FileFieldWidgetTest.php
index 9d8d41e3c973bc78b6b2a0e2ad09b59d1789b997..97d5db0a91fb0ca37e1e1b5a060d3b866b25b54f 100644
--- a/core/modules/file/tests/src/Functional/FileFieldWidgetTest.php
+++ b/core/modules/file/tests/src/Functional/FileFieldWidgetTest.php
@@ -470,6 +470,39 @@ public function testTemporaryFileRemovalExploitAnonymous() {
$this->doTestTemporaryFileRemovalExploit($victim_user, $attacker_user);
}
+ /**
+ * Tests configuring file field's allowed file extensions setting.
+ */
+ public function testFileExtensionsSetting() {
+ // Grant the admin user required permissions.
+ user_role_grant_permissions($this->adminUser->roles[0]->target_id, ['administer node fields']);
+
+ $type_name = 'article';
+ $field_name = strtolower($this->randomMachineName());
+ $this->createFileField($field_name, 'node', $type_name);
+ $field = FieldConfig::loadByName('node', $type_name, $field_name);
+ $field_id = $field->id();
+
+ // By default allowing .php files without .txt is not permitted.
+ $this->drupalGet("admin/structure/types/manage/$type_name/fields/$field_id");
+ $edit = ['settings[file_extensions]' => 'jpg php'];
+ $this->submitForm($edit, 'Save settings');
+ $this->assertSession()->pageTextContains('Add txt to the list of allowed extensions to securely upload files with a php extension. The txt extension will then be added automatically.');
+
+ // Test allowing .php and .txt.
+ $edit = ['settings[file_extensions]' => 'jpg php txt'];
+ $this->submitForm($edit, 'Save settings');
+ $this->assertSession()->pageTextContains('Saved ' . $field_name . ' configuration.');
+
+ // If the system is configured to allow insecure uploads, .txt is not
+ // required when allowing .php.
+ $this->config('system.file')->set('allow_insecure_uploads', TRUE)->save();
+ $this->drupalGet("admin/structure/types/manage/$type_name/fields/$field_id");
+ $edit = ['settings[file_extensions]' => 'jpg php'];
+ $this->submitForm($edit, 'Save settings');
+ $this->assertSession()->pageTextContains('Saved ' . $field_name . ' configuration.');
+ }
+
/**
* Helper for testing exploiting the temporary file removal using fid.
*
diff --git a/core/modules/file/tests/src/Functional/SaveUploadFormTest.php b/core/modules/file/tests/src/Functional/SaveUploadFormTest.php
index e3abbdf73c98d3826bae18e754eda8a280bcd886..8ff605cf5198e30fe7c9594623443334fa874c35 100644
--- a/core/modules/file/tests/src/Functional/SaveUploadFormTest.php
+++ b/core/modules/file/tests/src/Functional/SaveUploadFormTest.php
@@ -222,7 +222,7 @@ public function testHandleDangerousFile() {
'file_test_replace' => FileSystemInterface::EXISTS_REPLACE,
'files[file_test_upload][]' => $file_system->realpath($this->phpfile->uri),
'is_image_file' => FALSE,
- 'extensions' => 'php',
+ 'extensions' => 'php txt',
];
$this->drupalPostForm('file-test/save_upload_from_form_test', $edit, 'Submit');
@@ -251,6 +251,24 @@ public function testHandleDangerousFile() {
// Turn off insecure uploads.
$config->set('allow_insecure_uploads', 0)->save();
+
+ // Reset the hook counters.
+ file_test_reset();
+
+ $edit = [
+ 'file_test_replace' => FileSystemInterface::EXISTS_REPLACE,
+ 'files[file_test_upload]' => \Drupal::service('file_system')->realpath($this->phpfile->uri),
+ 'is_image_file' => FALSE,
+ 'extensions' => 'php',
+ ];
+
+ $this->drupalPostForm('file-test/upload', $edit, 'Submit');
+ $this->assertSession()->statusCodeEquals(200);
+ $this->assertSession()->pageTextContains('For security reasons, your upload has been rejected.');
+ $this->assertSession()->pageTextContains('Epic upload FAIL!');
+
+ // Check that the correct hooks were called.
+ $this->assertFileHooksCalled(['validate']);
}
/**
diff --git a/core/modules/file/tests/src/Functional/SaveUploadTest.php b/core/modules/file/tests/src/Functional/SaveUploadTest.php
index 6abe0ef9c990b0f220a78141dd638bdef745bc1e..6d15245da4cd0f0e05feee0adc686b49b760ed46 100644
--- a/core/modules/file/tests/src/Functional/SaveUploadTest.php
+++ b/core/modules/file/tests/src/Functional/SaveUploadTest.php
@@ -261,7 +261,7 @@ public function testHandleDangerousFile() {
'file_test_replace' => FileSystemInterface::EXISTS_REPLACE,
'files[file_test_upload]' => \Drupal::service('file_system')->realpath($this->phpfile->uri),
'is_image_file' => FALSE,
- 'extensions' => 'php',
+ 'extensions' => 'php txt',
];
$this->drupalPostForm('file-test/upload', $edit, 'Submit');
@@ -320,6 +320,21 @@ public function testHandleDangerousFile() {
// Reset the hook counters.
file_test_reset();
+
+ $edit = [
+ 'file_test_replace' => FileSystemInterface::EXISTS_REPLACE,
+ 'files[file_test_upload]' => \Drupal::service('file_system')->realpath($this->phpfile->uri),
+ 'is_image_file' => FALSE,
+ 'extensions' => 'php',
+ ];
+
+ $this->drupalPostForm('file-test/upload', $edit, 'Submit');
+ $this->assertSession()->statusCodeEquals(200);
+ $this->assertSession()->pageTextContains('For security reasons, your upload has been rejected.');
+ $this->assertSession()->pageTextContains('Epic upload FAIL!');
+
+ // Check that the correct hooks were called.
+ $this->assertFileHooksCalled(['validate']);
}
/**
diff --git a/core/modules/file/tests/src/Functional/Update/FileFieldFileExtensionsUpdateTest.php b/core/modules/file/tests/src/Functional/Update/FileFieldFileExtensionsUpdateTest.php
new file mode 100644
index 0000000000000000000000000000000000000000..66f0446dbc37766befb3f29a4b5684fbc678aed7
--- /dev/null
+++ b/core/modules/file/tests/src/Functional/Update/FileFieldFileExtensionsUpdateTest.php
@@ -0,0 +1,112 @@
+<?php
+
+namespace Drupal\Tests\file\Functional\Update;
+
+use Drupal\Core\Database\Database;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\FunctionalTests\Update\UpdatePathTestBase;
+
+/**
+ * Tests file_post_update_add_txt_if_allows_insecure_extensions().
+ *
+ * @group Update
+ * @group legacy
+ */
+class FileFieldFileExtensionsUpdateTest extends UpdatePathTestBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ protected static $modules = ['file'];
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setDatabaseDumpFiles() {
+ $this->databaseDumpFiles = [
+ __DIR__ . '/../../../../../system/tests/fixtures/update/drupal-8.8.0.bare.standard.php.gz',
+ ];
+ }
+
+ /**
+ * Tests adding txt extension to field that allow insecure extensions.
+ */
+ public function testInsecureUpdatesNotAllowed() {
+ $this->setAllowedExtensions('php jpg');
+ $this->runUpdates();
+ $this->assertSession()->statusCodeEquals('200');
+ $field = FieldConfig::load('node.article.field_image');
+ $this->assertSame('php jpg txt', $field->getSetting('file_extensions'));
+ }
+
+ /**
+ * Tests file fields that permit all extensions.
+ */
+ public function testAllFileTypesAllowed() {
+ $this->setAllowedExtensions('');
+ $this->runUpdates();
+ $this->assertSession()->statusCodeEquals('200');
+ $field = FieldConfig::load('node.article.field_image');
+ $this->assertSame('', $field->getSetting('file_extensions'));
+ }
+
+ /**
+ * Tests update when insecure uploads are allowed.
+ */
+ public function testInsecureUpdatesAllowed() {
+ $this->setAllowedExtensions('php');
+
+ // Do direct database updates to avoid dependencies.
+ $connection = Database::getConnection();
+ $config = $connection->select('config')
+ ->fields('config', ['data'])
+ ->condition('collection', '')
+ ->condition('name', 'system.file')
+ ->execute()
+ ->fetchField();
+ $config = unserialize($config);
+ $config['allow_insecure_uploads'] = TRUE;
+ $connection->update('config')
+ ->fields([
+ 'data' => serialize($config),
+ ])
+ ->condition('collection', '')
+ ->condition('name', 'system.file')
+ ->execute();
+
+ $this->runUpdates();
+ $this->assertSession()->pageTextContains('The system is configured to allow insecure file uploads. No file field updates are necessary.');
+ $this->assertSession()->statusCodeEquals('200');
+ $field = FieldConfig::load('node.article.field_image');
+ $this->assertSame('php', $field->getSetting('file_extensions'));
+ }
+
+ /**
+ * Sets the allowed extensions on the article image field.
+ *
+ * @param string $allowed_extensions
+ * The list of allowed extensions.
+ */
+ protected function setAllowedExtensions(string $allowed_extensions) {
+ // Do direct database updates to avoid dependencies.
+ $connection = Database::getConnection();
+
+ $config = $connection->select('config')
+ ->fields('config', ['data'])
+ ->condition('collection', '')
+ ->condition('name', 'field.field.node.article.field_image')
+ ->execute()
+ ->fetchField();
+ $config = unserialize($config);
+ $this->assertArrayHasKey('file_extensions', $config['settings']);
+ $config['settings']['file_extensions'] = $allowed_extensions;
+ $connection->update('config')
+ ->fields([
+ 'data' => serialize($config),
+ ])
+ ->condition('collection', '')
+ ->condition('name', 'field.field.node.article.field_image')
+ ->execute();
+ }
+
+}
diff --git a/core/modules/jsonapi/src/Controller/TemporaryJsonapiFileFieldUploader.php b/core/modules/jsonapi/src/Controller/TemporaryJsonapiFileFieldUploader.php
index a887aa7c96b5d4f58be65bb8ad4f7c3bee50cec7..fd60f11f374c5326a7715780a267eb1e3e7b5a1d 100644
--- a/core/modules/jsonapi/src/Controller/TemporaryJsonapiFileFieldUploader.php
+++ b/core/modules/jsonapi/src/Controller/TemporaryJsonapiFileFieldUploader.php
@@ -27,6 +27,8 @@
use Symfony\Component\Mime\MimeTypeGuesserInterface;
use Symfony\Component\Validator\ConstraintViolation;
+// cspell:ignore btxt
+
/**
* Reads data from an upload stream and creates a corresponding file entity.
*
@@ -403,24 +405,24 @@ protected function prepareFilename($filename, array &$validators) {
// If the file will be rejected anyway due to a disallowed extension, it
// should not be renamed; rather, we'll let file_validate_extensions()
// reject it below.
- $passes_validation = FALSE;
if (!empty($validators['file_validate_extensions'][0])) {
$file = File::create([]);
$file->setFilename($filename);
$passes_validation = empty(file_validate_extensions($file, $validators['file_validate_extensions'][0]));
+ // Only allow upload and rename to .txt if .txt files are allowed.
+ $passes_validation = $passes_validation && preg_match('/\btxt\b/', $validators['file_validate_extensions'][0]);
+ }
+ else {
+ // All file extensions are allowed.
+ $passes_validation = TRUE;
}
- if (empty($validators['file_validate_extensions'][0]) || $passes_validation) {
+
+ if ($passes_validation) {
if (substr($filename, -4) != '.txt') {
// The destination filename will also later be used to create the URI.
$filename .= '.txt';
}
$filename = file_munge_filename($filename, $validators['file_validate_extensions'][0] ?? '');
-
- // The .txt extension may not be in the allowed list of extensions. We
- // have to add it here or else the file upload will fail.
- if (!empty($validators['file_validate_extensions'][0])) {
- $validators['file_validate_extensions'][0] .= ' txt';
- }
}
}
}
diff --git a/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php b/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php
index b63c030c6e5284ec64b5e777ebc93c301c74d6ab..39299b4a54a12f690e6e35d75cfd06cba584be7a 100644
--- a/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php
+++ b/core/modules/jsonapi/tests/src/Functional/FileUploadTest.php
@@ -627,11 +627,9 @@ public function testFileUploadMaliciousExtension() {
$this->assertResponseData($expected, $response);
$this->assertFileExists('public://foobar/example.php_.txt');
- // Add php as an allowed format. Allow insecure uploads still being FALSE
- // should still not allow this. So it should still have a .txt extension
- // appended even though it is not in the list of allowed extensions.
- $this->field->setSetting('file_extensions', 'php')
- ->save();
+ // Add .php and .txt as allowed extensions. Since 'allow_insecure_uploads'
+ // is FALSE, .php files should be renamed to have a .txt extension.
+ $this->field->setSetting('file_extensions', 'php txt')->save();
$this->rebuildAll();
$response = $this->fileRequest($uri, $php_string, ['Content-Disposition' => 'filename="example_2.php"']);
@@ -698,6 +696,18 @@ public function testFileUploadMaliciousExtension() {
$this->assertResponseData($expected, $response);
$this->assertFileExists('public://foobar/example_6.cgi_.png_.txt');
+ // Add .php as an allowed extension without .txt. Since insecure uploads are
+ // are not allowed, .php files will be rejected.
+ $this->field->setSetting('file_extensions', 'php')->save();
+ $this->rebuildAll();
+
+ $response = $this->fileRequest($uri, $php_string, ['Content-Disposition' => 'filename="example_7.php"']);
+ $this->assertResourceErrorResponse(422, "Unprocessable Entity: file validation failed.\nFor security reasons, your upload has been rejected.", $uri, $response);
+
+ // Make sure that no file was saved.
+ $this->assertFileNotExists('public://foobar/example_7.php');
+ $this->assertFileNotExists('public://foobar/example_7.php.txt');
+
// Now allow insecure uploads.
\Drupal::configFactory()
->getEditable('system.file')
diff --git a/core/modules/rest/tests/src/Functional/FileUploadResourceTestBase.php b/core/modules/rest/tests/src/Functional/FileUploadResourceTestBase.php
index a6355c827500b81494177144af6391bbbd97bbc4..e66259854313f6e2fca89eb7242a620667df4910 100644
--- a/core/modules/rest/tests/src/Functional/FileUploadResourceTestBase.php
+++ b/core/modules/rest/tests/src/Functional/FileUploadResourceTestBase.php
@@ -523,11 +523,9 @@ public function testFileUploadMaliciousExtension() {
$this->assertResponseData($expected, $response);
$this->assertFileExists('public://foobar/example.php_.txt');
- // Add php as an allowed format. Allow insecure uploads still being FALSE
- // should still not allow this. So it should still have a .txt extension
- // appended even though it is not in the list of allowed extensions.
- $this->field->setSetting('file_extensions', 'php')
- ->save();
+ // Add .php and .txt as allowed extensions. Since 'allow_insecure_uploads'
+ // is FALSE, .php files should be renamed to have a .txt extension.
+ $this->field->setSetting('file_extensions', 'php txt')->save();
$this->refreshTestStateAfterRestConfigChange();
$response = $this->fileRequest($uri, $php_string, ['Content-Disposition' => 'filename="example_2.php"']);
@@ -594,6 +592,18 @@ public function testFileUploadMaliciousExtension() {
$this->assertResponseData($expected, $response);
$this->assertFileExists('public://foobar/example_6.cgi_.png_.txt');
+ // Add .php as an allowed extension without .txt. Since insecure uploads are
+ // not allowed, .php files will be rejected.
+ $this->field->setSetting('file_extensions', 'php')->save();
+ $this->refreshTestStateAfterRestConfigChange();
+
+ $response = $this->fileRequest($uri, $php_string, ['Content-Disposition' => 'filename="example_7.php"']);
+ $this->assertResourceErrorResponse(422, "Unprocessable Entity: file validation failed.\nFor security reasons, your upload has been rejected.", $response);
+
+ // Make sure that no file was saved.
+ $this->assertFileNotExists('public://foobar/example_7.php');
+ $this->assertFileNotExists('public://foobar/example_7.php.txt');
+
// Now allow insecure uploads.
\Drupal::configFactory()
->getEditable('system.file')