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    * 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   *
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  package org.apache.james.smtpserver.core.filter.fastfail;
  
  import java.util.Iterator;
  
  import javax.mail.MessagingException;
  import javax.mail.internet.MimeMessage;
  
  import org.apache.avalon.framework.configuration.Configurable;
  import org.apache.avalon.framework.configuration.Configuration;
  import org.apache.avalon.framework.configuration.ConfigurationException;
  import org.apache.avalon.framework.logger.AbstractLogEnabled;
  import org.apache.james.dsn.DSNStatus;
  import org.apache.james.smtpserver.MessageHandler;
  import org.apache.james.smtpserver.SMTPSession;
  import org.apache.james.util.scanner.SpamAssassinInvoker;
  import org.apache.mailet.Mail;
  
  /**
   * This MessageHandler could be used to check message against spamd before
   * accept the email. So its possible to reject a message on smtplevel if a
   * configured hits amount is reached. The handler add the follow attributes to
   * the mail object:<br>
   * org.apache.james.spamassassin.status - Holds the status
   * org.apache.james.spamassassin.flag - Holds the flag <br>
   * 
   * Sample Configuration: <br>
   * <br>
   * &lt;handler class="org.apache.james.smtpserver.SpamAssassinHandler"&gt;
   * &lt;spamdHost&gt;localhost&lt;/spamdHost&gt;
   * &lt;spamdPort&gt;783&lt;/spamdPort&gt; <br>
   * &lt;spamdRejectionHits&gt;15.0&lt;/spamdRejectionHits&gt;
   * &lt;checkAuthNetworks&gt;false&lt;/checkAuthNetworks&gt; &lt;/handler&gt;
   */
  public class SpamAssassinHandler extends AbstractLogEnabled implements
          MessageHandler, Configurable {
  
      /**
       * The port spamd is listen on
       */
      private int spamdPort = 783;
  
      /**
       * The host spamd is runnin on
       */
      private String spamdHost = "localhost";
  
      /**
       * The hits on which the message get rejected
       */
      private double spamdRejectionHits = 0.0;
  
      private boolean checkAuthNetworks = false;
  
      /**
       * @see org.apache.avalon.framework.configuration.Configurable#configure(Configuration)
       */
      public void configure(Configuration arg0) throws ConfigurationException {
          Configuration spamdHostConf = arg0.getChild("spamdHost", false);
          if (spamdHostConf != null) {
              setSpamdHost(spamdHostConf.getValue("localhost"));
          }
  
          Configuration spamdPortConf = arg0.getChild("spamdPort", false);
          if (spamdPortConf != null) {
              setSpamdPort(spamdPortConf.getValueAsInteger(783));
          }
  
          Configuration spamdRejectionHitsConf = arg0.getChild(
                  "spamdRejectionHits", false);
          if (spamdRejectionHitsConf != null) {
              setSpamdRejectionHits(spamdRejectionHitsConf.getValueAsDouble(0.0));
          }
  
          Configuration configRelay = arg0.getChild("checkAuthNetworks", false);
          if (configRelay != null) {
              setCheckAuthNetworks(configRelay.getValueAsBoolean(false));
          }
  
      }
 
     /**
      * Set to true if AuthNetworks should be included in the EHLO check
      * 
      * @param checkAuthNetworks
      *            Set to true to enable
      */
     public void setCheckAuthNetworks(boolean checkAuthNetworks) {
         this.checkAuthNetworks = checkAuthNetworks;
     }
 
     /**
      * Set the host the spamd daemon is running at
      * 
      * @param spamdHost
      *            The spamdHost
      */
     public void setSpamdHost(String spamdHost) {
         this.spamdHost = spamdHost;
     }
 
     /**
      * Set the port the spamd damon is listen on
      * 
      * @param spamdPort
      *            the spamdPort
      */
     public void setSpamdPort(int spamdPort) {
         this.spamdPort = spamdPort;
     }
 
     /**
      * Set the hits on which the message will be rejected.
      * 
      * @param spamdRejectionHits
      *            The hits
      */
     public void setSpamdRejectionHits(double spamdRejectionHits) {
         this.spamdRejectionHits = spamdRejectionHits;
 
     }
 
     /**
      * @see org.apache.james.smtpserver.MessageHandler#onMessage(SMTPSession)
      */
     public void onMessage(SMTPSession session) {
 
         // Not scan the message if relaying allowed
         if (session.isRelayingAllowed() && !checkAuthNetworks) {
             return;
         }
 
         try {
             Mail mail = session.getMail();
             MimeMessage message = mail.getMessage();
             SpamAssassinInvoker sa = new SpamAssassinInvoker(spamdHost,
                     spamdPort);
             sa.scanMail(message);
 
             Iterator headers = sa.getHeadersAsAttribute().keySet().iterator();
 
             // Add the headers
             while (headers.hasNext()) {
                 String key = headers.next().toString();
 
                 mail.setAttribute(key, (String) sa.getHeadersAsAttribute().get(
                         key));
             }
 
             // Check if rejectionHits was configured
             if (spamdRejectionHits > 0) {
                 try {
                     double hits = Double.parseDouble(sa.getHits());
 
                     // if the hits are bigger the rejectionHits reject the
                     // message
                     if (spamdRejectionHits <= hits) {
                         String responseString = "554 "
                                 + DSNStatus.getStatus(DSNStatus.PERMANENT,
                                         DSNStatus.SECURITY_OTHER)
                                 + " This message reach the spam hits treshold. Please contact the Postmaster if the email is not SPAM. Message rejected";
                         StringBuffer buffer = new StringBuffer(256).append(
                                 "Rejected message from ").append(
                                 session.getState().get(SMTPSession.SENDER)
                                         .toString()).append(" from host ")
                                 .append(session.getRemoteHost()).append(" (")
                                 .append(session.getRemoteIPAddress()).append(
                                         ") " + responseString).append(
                                         ". Required rejection hits: "
                                                 + spamdRejectionHits
                                                 + " hits: " + hits);
                         getLogger().info(buffer.toString());
                         session.writeResponse(responseString);
 
                         // Message reject .. abort it!
                         session.abortMessage();
                     }
                 } catch (NumberFormatException e) {
                     // hits unknown
                 }
             }
         } catch (MessagingException e) {
             getLogger().error(e.getMessage());
         }
 
     }
 }