| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.drill.exec.server.rest; |
| |
| import javax.servlet.http.HttpServletRequest; |
| import javax.servlet.http.HttpSession; |
| import java.security.SecureRandom; |
| import java.util.Base64; |
| |
| public class WebUtils { |
| |
| /** |
| * Retrieves the CSRF protection token from the HTTP request. |
| * |
| * @param request HTTP request that contains a session that stores a CSRF protection token. |
| * If there is no session, that means that authentication is disabled. |
| * @return CSRF protection token, or an empty string if there is no session present. |
| */ |
| public static String getCsrfTokenFromHttpRequest(HttpServletRequest request) { |
| // No need to create a session if not present (i.e. if a user is logged in) |
| HttpSession session = request.getSession(false); |
| return session == null ? "" : (String) session.getAttribute(WebServerConstants.CSRF_TOKEN); |
| } |
| |
| /** |
| * Generates a BASE64 encoded CSRF token from randomly generated 256-bit buffer |
| * according to the <a href="https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html">OWASP CSRF Prevention Cheat Sheet</a> |
| * |
| * @return randomly generated CSRF token. |
| */ |
| public static String generateCsrfToken() { |
| byte[] buffer = new byte[32]; |
| new SecureRandom().nextBytes(buffer); |
| return Base64.getUrlEncoder().withoutPadding().encodeToString(buffer); |
| } |
| } |