| /* |
| * 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.struts2.interceptor.csp; |
| |
| import com.opensymphony.xwork2.ActionInvocation; |
| import com.opensymphony.xwork2.interceptor.AbstractInterceptor; |
| import com.opensymphony.xwork2.interceptor.PreResultListener; |
| import java.net.URI; |
| import java.util.Optional; |
| import javax.servlet.http.HttpServletResponse; |
| |
| /** |
| * Interceptor that implements Content Security Policy on incoming requests used to protect against |
| * common XSS and data injection attacks. Uses {@link CspSettings} to add appropriate Content Security Policy header |
| * to the response. These headers determine what the browser will consider a policy violation and the browser's behavior |
| * when a violation occurs. A detailed explanation of CSP can be found <a href="https://csp.withgoogle.com/docs/index.html">here</a>. |
| * |
| * @see <a href="https://csp.withgoogle.com/docs/index.html">https://csp.withgoogle.com/docs/index.html/</a> |
| * @see CspSettings |
| * @see DefaultCspSettings |
| **/ |
| public final class CspInterceptor extends AbstractInterceptor implements PreResultListener { |
| private final CspSettings settings = new DefaultCspSettings(); |
| |
| @Override |
| public String intercept(ActionInvocation invocation) throws Exception { |
| invocation.addPreResultListener(this); |
| return invocation.invoke(); |
| } |
| |
| public void beforeResult(ActionInvocation invocation, String resultCode) { |
| HttpServletResponse response = invocation.getInvocationContext().getServletResponse(); |
| settings.addCspHeaders(response); |
| } |
| |
| public void setReportUri(String reportUri) { |
| Optional<URI> uri = buildUri(reportUri); |
| if (!uri.isPresent()) { |
| throw new IllegalArgumentException("Could not parse configured report URI for CSP interceptor: " + reportUri); |
| } |
| |
| if (!uri.get().isAbsolute() && !reportUri.startsWith("/")) { |
| throw new IllegalArgumentException("Illegal configuration: report URI is not relative to the root. Please set a report URI that starts with /"); |
| } |
| |
| settings.setReportUri(reportUri); |
| } |
| |
| private Optional<URI> buildUri(String reportUri) { |
| try { |
| return Optional.of(URI.create(reportUri)); |
| } catch (IllegalArgumentException ignored) { |
| } |
| |
| return Optional.empty(); |
| } |
| |
| public void setEnforcingMode(String value){ |
| boolean enforcingMode = Boolean.parseBoolean(value); |
| settings.setEnforcingMode(enforcingMode); |
| } |
| } |