1  /*
     2  * Licensed to the Apache Software Foundation (ASF) under one or more
     3  *  contributor license agreements.  The ASF licenses this file to You
     4  * under the Apache License, Version 2.0 (the "License"); you may not
     5  * use this file except in compliance with the License.
     6  * You may obtain a copy of the License at
     7  *
     8  *     http://www.apache.org/licenses/LICENSE-2.0
     9  *
    10  * Unless required by applicable law or agreed to in writing, software
    11  * distributed under the License is distributed on an "AS IS" BASIS,
    12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  * See the License for the specific language governing permissions and
    14  * limitations under the License.  For additional information regarding
    15  * copyright in this work, please see the NOTICE file in the top level
    16  * directory of this distribution.
    17  */
    18  
    19  package org.apache.roller.weblogger.ui.core.filters;
    20  
    21  import java.io.IOException;
    22  import javax.servlet.Filter;
    23  import javax.servlet.FilterChain;
    24  import javax.servlet.FilterConfig;
    25  import javax.servlet.ServletException;
    26  import javax.servlet.ServletRequest;
    27  import javax.servlet.ServletResponse;
    28  import javax.servlet.http.HttpServletRequest;
    29  import javax.servlet.http.HttpServletResponse;
    30  import org.apache.commons.logging.Log;
    31  import org.apache.commons.logging.LogFactory;
    32  import org.apache.roller.weblogger.util.IPBanList;
    33  
    34  
    35  /**
    36   * Simple IP restriction filter.  Denied clients get a 404 reponse.
    37   *
    38   * @web.filter name="IPBanFilter"
    39   */
         /* 
    P/P   *  Method: void org.apache.roller.weblogger.ui.core.filters.IPBanFilter()
          */
    40  public class IPBanFilter implements Filter {
    41      
             /* 
    P/P       *  Method: org.apache.roller.weblogger.ui.core.filters.IPBanFilter__static_init
              * 
              *  Postconditions:
              *    init'ed(log)
              */
    42      private static Log log = LogFactory.getLog(IPBanFilter.class);
    43      
    44      
    45      public void init(FilterConfig filterConfig) throws ServletException {
    46          
                 /* 
    P/P           *  Method: void init(FilterConfig)
                  * 
                  *  Preconditions:
                  *    log != null
                  */
    47          log.info("INIT IPBanFilter");
    48      }
    49      
    50      
    51      public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
    52              throws IOException, ServletException {
    53          
                 /* 
    P/P           *  Method: void doFilter(ServletRequest, ServletResponse, FilterChain)
                  * 
                  *  Preconditions:
                  *    org/apache/roller/weblogger/util/IPBanList.instance != null
                  *    init'ed(org/apache/roller/weblogger/util/IPBanList.instance.bannedIpsFile)
                  *    req != null
                  *    (soft) chain != null
                  *    (soft) log != null
                  *    (soft) init'ed(org/apache/roller/weblogger/util/IPBanList.instance.bannedIps)
                  *    (soft) init'ed(org/apache/roller/weblogger/util/IPBanList.instance.bannedIpsFile.myLastModified)
                  *    (soft) org/apache/roller/weblogger/util/IPBanList.log != null
                  *    (soft) res != null
                  * 
                  *  Postconditions:
                  *    org/apache/roller/weblogger/util/IPBanList.instance.bannedIps == One-of{old org/apache/roller/weblogger/util/IPBanList.instance.bannedIps, &new HashSet(loadBannedIps#1)}
                  *    (soft) init'ed(org/apache/roller/weblogger/util/IPBanList.instance.bannedIps)
                  *    init'ed(org/apache/roller/weblogger/util/IPBanList.instance.bannedIpsFile.myLastModified)
                  *    new HashSet(loadBannedIps#1) num objects <= 1
                  */
    54          HttpServletRequest request = (HttpServletRequest) req;
    55          HttpServletResponse response = (HttpServletResponse) res;
    56          
    57          // check if client is allowed
    58          if(IPBanList.getInstance().isBanned(request.getRemoteAddr())) {
    59              log.debug("BANNED "+request.getRemoteAddr());
    60              response.sendError(HttpServletResponse.SC_NOT_FOUND);
    61              return;
    62          } else {
    63              chain.doFilter(request, response);
    64          }
    65      }
    66      
    67      
             /* 
    P/P       *  Method: void destroy()
              */
    68      public void destroy() {}
    69      
    70  }