/*

  * 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.shiro.web.filter.authz;

 import org.apache.shiro.config.ConfigurationException;

 import org.apache.shiro.util.StringUtils;

 import org.apache.shiro.web.util.WebUtils;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 import javax.servlet.http.HttpServletRequest;

 import java.io.IOException;

 /**

  * A Filter that requires the request to be on a specific port, and if not, redirects to the same URL on that port.

  * <p/>

  * Example config:

  * <pre>

  * [filters]

  * port.port = 80

  * <p/>

  * [urls]

  * /some/path/** = port

  * # override for just this path:

  * /another/path/** = port[8080]

  * </pre>

  *

  * @since 1.0

  */

 public class PortFilter extends AuthorizationFilter {

     public static final int DEFAULT_HTTP_PORT = 80;

     public static final String HTTP_SCHEME = "http";

     private int port = DEFAULT_HTTP_PORT;

     public int getPort() {

         return port;

     }

     public void setPort(int port) {

         this.port = port;

     }

     protected int toPort(Object mappedValue) {

         String[] ports = (String[]) mappedValue;

         if (ports == null || ports.length == 0) {

             return getPort();

         }

         if (ports.length > 1) {

             throw new ConfigurationException("PortFilter can only be configured with a single port.  You have " +

                     "configured " + ports.length + ": " + StringUtils.toString(ports));

         }

         return Integer.parseInt(ports[0]);

     }

     protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) throws Exception {

         int requiredPort = toPort(mappedValue);

         int requestPort = request.getServerPort();

         return requiredPort == requestPort;

     }

     protected String getScheme(String requestScheme, int port) {

         if (port == DEFAULT_HTTP_PORT) {

             return HTTP_SCHEME;

         } else if (port == SslFilter.DEFAULT_HTTPS_PORT) {

             return SslFilter.HTTPS_SCHEME;

         } else {

             return requestScheme;

         }

     }

     /**

      * Redirects the request to the same exact incoming URL, but with the port listed in the filter's configuration.

      *

      * @param request     the incoming <code>ServletRequest</code>

      * @param response    the outgoing <code>ServletResponse</code>

      * @param mappedValue the config specified for the filter in the matching request's filter chain.

      * @return {@code false} always to force a redirect.

      */

     @Override

     protected boolean onAccessDenied(ServletRequest request, ServletResponse response, Object mappedValue) throws IOException {

         //just redirect to the specified port:

         int port = toPort(mappedValue);

         String scheme = getScheme(request.getScheme(), port);

         StringBuilder sb = new StringBuilder();

         sb.append(scheme).append("://");

         sb.append(request.getServerName());

         if (port != DEFAULT_HTTP_PORT && port != SslFilter.DEFAULT_HTTPS_PORT) {

             sb.append(":");

             sb.append(port);

         }

         if (request instanceof HttpServletRequest) {

             sb.append(WebUtils.toHttp(request).getRequestURI());

             String query = WebUtils.toHttp(request).getQueryString();

             if (query != null) {

                 sb.append("?").append(query);

             }

         }

         WebUtils.issueRedirect(request, response, sb.toString());

         return false;

     }

 }