fix(dav): file drop nickname

Signed-off-by: skjnldsv <skjnldsv@protonmail.com>

Author: skjnldsv

apps/dav/lib/Files/Sharing/FilesDropPlugin.php

@@ -7,6 +7,7 @@
 
 use OC\Files\View;
 use OCP\Share\IShare;
+use Sabre\DAV\Exception\BadRequest;
 use Sabre\DAV\Exception\MethodNotAllowed;
 use Sabre\DAV\ServerPlugin;
 use Sabre\HTTP\RequestInterface;
@@ -64,14 +65,28 @@ public function beforeMethod(RequestInterface $request, ResponseInterface $respo
 		// Extract the attributes for the file request
 		$isFileRequest = false;
 		$attributes = $this->share->getAttributes();
-		$nickName = $request->hasHeader('X-NC-Nickname') ? urldecode($request->getHeader('X-NC-Nickname')) : null;
+		$nickName = $request->hasHeader('X-NC-Nickname') ? trim(urldecode($request->getHeader('X-NC-Nickname'))) : null;
 		if ($attributes !== null) {
 			$isFileRequest = $attributes->getAttribute('fileRequest', 'enabled') === true;
 		}
 
 		// We need a valid nickname for file requests
-		if ($isFileRequest && ($nickName == null || trim($nickName) === '')) {
-			throw new MethodNotAllowed('Nickname is required for file requests');
+		if ($isFileRequest && !$nickName) {
+			throw new BadRequest('Nickname is required for file requests');
+		}
+		
+		if ($nickName !== null) {
+			try {
+				$this->view->verifyPath($path, $nickName);
+			} catch (\Exception $e) {
+				// If the path is not valid, we throw an exception
+				throw new BadRequest('Invalid nickname: ' . $nickName);
+			}
+
+			// Forbid nicknames starting with a dot
+			if (str_starts_with($nickName, '.')) {
+				throw new BadRequest('Invalid nickname: ' . $nickName);
+			}
 		}
 
 		// If this is a file request we need to create a folder for the user

build/integration/filesdrop_features/filesdrop.feature

@@ -47,7 +47,7 @@ Feature: FilesDrop
     And Downloading file "/drop/a.txt"
     Then Downloaded content should be "abc"
 
-  Scenario: Files drop forbis MKCOL
+  Scenario: Files drop forbid MKCOL
     Given user "user0" exists
     And As an "user0"
     And user "user0" created a folder "/drop"
@@ -90,3 +90,42 @@ Feature: FilesDrop
     Then Downloaded content should be "abc"
     And Downloading file "/drop/Mallory/a (2).txt"
     Then Downloaded content should be "def"
+
+  Scenario: Files request drop with invalid nickname with slashes
+    Given user "user0" exists
+    And As an "user0"
+    And user "user0" created a folder "/drop"
+    And as "user0" creating a share with
+      | path | drop |
+      | shareType | 4 |
+      | permissions | 4 |
+      | attributes | [{"scope":"fileRequest","key":"enabled","value":true}] |
+      | shareWith |  |
+    When Dropping file "/folder/a.txt" with "abc" as "Alice/Bob/Mallory"
+    Then the HTTP status code should be "400"
+
+  Scenario: Files request drop with invalid nickname with forbidden characters
+    Given user "user0" exists
+    And As an "user0"
+    And user "user0" created a folder "/drop"
+    And as "user0" creating a share with
+      | path | drop |
+      | shareType | 4 |
+      | permissions | 4 |
+      | attributes | [{"scope":"fileRequest","key":"enabled","value":true}] |
+      | shareWith |  |
+    When Dropping file "/folder/a.txt" with "abc" as ".htaccess"
+    Then the HTTP status code should be "400"
+
+  Scenario: Files request drop with invalid nickname with forbidden characters
+    Given user "user0" exists
+    And As an "user0"
+    And user "user0" created a folder "/drop"
+    And as "user0" creating a share with
+      | path | drop |
+      | shareType | 4 |
+      | permissions | 4 |
+      | attributes | [{"scope":"fileRequest","key":"enabled","value":true}] |
+      | shareWith |  |
+    When Dropping file "/folder/a.txt" with "abc" as ".Mallory"
+    Then the HTTP status code should be "400"