package org.apache.continuum.webdav;
   
   /*
    * 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.
   */
  
  import org.apache.continuum.buildagent.configuration.BuildAgentConfigurationService;
  import org.apache.jackrabbit.webdav.DavException;
  import org.apache.jackrabbit.webdav.DavSessionProvider;
  import org.apache.jackrabbit.webdav.WebdavRequest;
  import org.codehaus.plexus.util.Base64;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import javax.servlet.http.HttpServletResponse;
  
  public class ContinuumBuildAgentDavSessionProvider
      implements DavSessionProvider
  {
      private Logger log = LoggerFactory.getLogger( this.getClass() );
  
      private BuildAgentConfigurationService buildAgentConfigurationService;
  
      public ContinuumBuildAgentDavSessionProvider( BuildAgentConfigurationService buildAgentConfigurationService )
      {
          this.buildAgentConfigurationService = buildAgentConfigurationService;
      }
  
      public boolean attachSession( WebdavRequest request )
          throws DavException
      {
          if ( !isAuthorized( request ) )
          {
              throw new DavException( HttpServletResponse.SC_UNAUTHORIZED );
          }
  
          request.setDavSession( new ContinuumBuildAgentDavSession() );
  
          return true;
      }
  
      public void releaseSession( WebdavRequest request )
      {
          request.setDavSession( null );
      }
  
      private boolean isAuthorized( WebdavRequest request )
      {
          String header = request.getHeader( "Authorization" );
  
          // in tomcat this is : authorization=Basic YWRtaW46TWFuYWdlMDc=
          if ( header == null )
          {
              header = request.getHeader( "authorization" );
          }
  
          if ( ( header != null ) && header.startsWith( "Basic " ) )
          {
              String base64Token = header.substring( 6 );
              String token = new String( Base64.decodeBase64( base64Token.getBytes() ) );
  
              String password = "";
              int delim = token.indexOf( ':' );
  
              if ( delim != ( -1 ) )
              {
                  password = token.substring( delim + 1 );
              }
  
              if ( buildAgentConfigurationService.getSharedSecretPassword() != null &&
                  buildAgentConfigurationService.getSharedSecretPassword().equals( password ) )
              {
                  log.debug( "Password matches configured shared key in continuum build agent." );
                  return true;
              }
          }
  
          log.warn( "Not authorized to access the working copy." );
  
          return false;
      }
  }