hostage/src/org/alfresco/jlan/netbios/NetBIOSDatagram.java

/*
 * Copyright (C) 2006-2010 Alfresco Software Limited.
 *
 * This file is part of Alfresco
 *
 * Alfresco is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Alfresco is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
 */

package org.alfresco.jlan.netbios;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.UnknownHostException;

import org.alfresco.jlan.util.DataPacker;

/**
 * NetBIOS datagram class
 * 
 * <p>Used for sending/receiving NetBIOS broadcast datagrams that are used for name lookups and registration.
 *
 * @author gkspencer
 */
public class NetBIOSDatagram {

  //	Datagram types

  public static final int DIRECT_UNIQUE		= 0x10;
  public static final int DIRECT_GROUP		= 0x11;
  public static final int BROADCAST				= 0x12;
  public static final int DATAGRAM_ERROR	= 0x13;
  public static final int DATAGRAM_QUERY	= 0x14;
  public static final int POSITIVE_RESP 	= 0x15;
  public static final int NEGATIVE_RESP		= 0x16;

  //	Datagram flags

  public static final int FLG_MOREFRAGMENTS		= 0x01;
  public static final int FLG_FIRSTPKT				= 0x02;

  //	Default NetBIOS packet buffer size to allocate

  public static final int DEFBUFSIZE			= 4096;

  //	NetBIOS datagram offsets

  public static final int NB_MSGTYPE			= 0;
  public static final int NB_FLAGS				= 1;
  public static final int NB_DATAGRAMID		= 2;
  public static final int NB_SOURCEIP			= 4;
  public static final int NB_SOURCEPORT		= 8;
  public static final int NB_DATAGRAMLEN	= 10;
  public static final int NB_PKTOFFSET		= 12;
  public static final int NB_FROMNAME			= 14;
  public static final int NB_TONAME				= 48;
  public static final int NB_USERDATA			= 82;

  public static final int NB_MINLENGTH		= 82;
  public static final int NB_MINSMBLEN		= 100;

  //	NetBIOS packet buffer

  protected byte[] m_buf;

  //	Next available datagram id

  private static int	m_nextId;

	/**
	 * NetBIOS Datagram constructor
	 */

	public NetBIOSDatagram() {

	  //  Allocaet a NetBIOS packet buffer

	  m_buf = new byte [ DEFBUFSIZE];
	}

	/**
	 * Create a new NetBIOS datagram using the specified packet buffer.
	 *
	 * @param pkt byte[]
	 */
	public NetBIOSDatagram ( byte[] pkt) {
	  m_buf = pkt;
	}

	/**
	 * Create a new NetBIOS datagram with the specified buffer size.
	 *
	 * @param bufSize int
	 */
	public NetBIOSDatagram ( int bufSize) {
	  m_buf = new byte [ bufSize];
	}

	/**
	 * Return the next available datagram id.
	 */
	public final static synchronized int getNextDatagramId() {

	  //  Update and return the next available datagram id

	  return m_nextId++;
	}

	/**
	 * Return the NetBIOS buffer.
	 *
	 * @return byte[]
	 */
	public final byte[] getBuffer() {
	  return m_buf;
	}

	/**
	 * Get the datagram id.
	 *
	 * @return int
	 */
	public final int getDatagramId() {
	  return DataPacker.getIntelShort ( m_buf, NB_DATAGRAMID);
	}

	/**
	 * Get the datagram destination name.
	 *
	 * @return NetBIOSName
	 */
	public final NetBIOSName getDestinationName() {

	  //  Decode the NetBIOS name to a string

	  String name = NetBIOSSession.DecodeName ( m_buf, NB_TONAME + 1);
	  if ( name != null) {

	    //  Convert the name string to a NetBIOS name

	    NetBIOSName nbName = new NetBIOSName(name.substring(0,14),name.charAt(15),false);
	    if ( getMessageType() == DIRECT_GROUP)
	      nbName.setGroup(true);
	    return nbName;
	  }
	  return null;
	}

	/**
	 * Return the datagram flags value.
	 *
	 * @return int
	 */
	public final int getFlags() {
	  return m_buf [ NB_FLAGS] & 0xFF;
	}

	/**
	 * Return the datagram length.
	 *
	 * @return int
	 */
	public final int getLength() {
	  return DataPacker.getShort ( m_buf, NB_DATAGRAMLEN);
	}

	/**
	 * Return the user data length
	 * 
	 * @return int
	 */
	public final int getDataLength() {
	  return getLength() - NB_USERDATA;
	}
	
	/**
	 * Get the NetBIOS datagram message type.
	 *
	 * @return int
	 */
	public final int getMessageType() {
	  return m_buf [ NB_MSGTYPE] & 0xFF;
	}

	/**
	 * Return the datagram source IP address.
	 *
	 * @return byte[]
	 */
	public final byte[] getSourceIPAddress() {

	  //  Allocate a 4 byte array for the IP address

	  byte[] ipaddr = new byte [ 4];

	  //  Copy the IP address bytes from the datagram

	  for ( int i = 0; i < 4; i++)
	    ipaddr [ i] = m_buf [ NB_SOURCEIP + i];

	  //  Return the IP address bytes

	  return ipaddr;
	}

	/**
	 * Return the datagram source IP address, as a string
	 * 
	 * @return String
	 */
	public final String getSourceAddress() {
		
		//	Get the IP address
		
		byte[] addr = getSourceIPAddress();
		
		//	Build the IP address string
		
		StringBuffer addrStr = new StringBuffer();
		
		addrStr.append(addr[0]);
		addrStr.append(".");
		addrStr.append(addr[1]);
		addrStr.append(".");
		addrStr.append(addr[2]);
		addrStr.append(".");
		addrStr.append(addr[3]);
		
		return addrStr.toString();
	}
	
	/**
	 * Get the source NetBIOS name.
	 *
	 * @return java.lang.String
	 */
	public final NetBIOSName getSourceName() {

	  //  Decode the NetBIOS name string

	  String name = NetBIOSSession.DecodeName ( m_buf, NB_FROMNAME + 1);

	  //  Convert the name to a NetBIOS name

	  if ( name != null) {

	    //  Convert the name string to a NetBIOS name

	    NetBIOSName nbName = new NetBIOSName(name.substring(0,14),name.charAt(15),false);
	    return nbName;
	  }
	  return null;
	}

	/**
	 * Get the source port/socket for the datagram.
	 *
	 * @return int
	 */
	public final int getSourcePort() {
	  return DataPacker.getIntelShort ( m_buf, NB_SOURCEPORT);
	}

	/**
	 * Check if the user data is an SMB packet
	 * 
	 * @return boolean
	 */
	public final boolean isSMBData() {
	  if ( m_buf[NB_USERDATA]   == (byte) 0xFF &&
	  		 m_buf[NB_USERDATA+1] == (byte) 'S'  &&
	  		 m_buf[NB_USERDATA+2] == (byte) 'M'  &&
	  		 m_buf[NB_USERDATA+3] == (byte) 'B'  &&
	  		 getLength() >= NB_MINSMBLEN)
	  	return true;
	  return false;
	}
	
	/**
	 * Return the message type as a string
	 *
	 * @return String
	 */

	public final String getMessageTypeString() {

	  //  Determine the message type

	  String typ = null;

	  switch ( getMessageType()) {
	    case DIRECT_GROUP:
	      typ = "DIRECT GROUP";
	      break;
	    case DIRECT_UNIQUE:
	      typ = "DIRECT UNIQUE";
	      break;
	    case DATAGRAM_ERROR:
	      typ = "DATAGRAM ERROR";
	      break;
	    case DATAGRAM_QUERY:
	      typ = "DATAGRAM QUERY";
	      break;
	    case BROADCAST:
	      typ = "BROADCAST";
	      break;
	    case POSITIVE_RESP:
	      typ = "POSITIVE RESP";
	      break;
	    case NEGATIVE_RESP:
	      typ = "NEGATIVE RESP";
	      break;
	    default:
	      typ = "UNKNOWN";
	      break;
	  }

	  //  Return the message type string

	  return typ;
	}

	/**
	 * Send a datagram to the specified NetBIOS name using the global NetBIOS datagram socket
	 *
	 * @param dgramTyp    Datagram type
	 * @param fromName    From NetBIOS name
	 * @param fromNameType From NetBIOS name type.
	 * @param toName      To NetBIOS name
	 * @param toNameType  To NetBIOS name type.
	 * @param userData    User data buffer
	 * @param userLen     User data length.
	 * @param userOff     Offset of data within user buffer.
	 * @param addr 				Address to send to
	 * @param port				Port to send to
	 * @exception java.io.IOException		Error occurred sending datagram
	 * @exception UnknownHostException 	Failed to generate the broadcast mask for the network
	 */
	public final void SendDatagram ( int dgramTyp, String fromName, char fromNameType, String toName, char toNameType,
																	 byte[] userData, int userLen, int userOff, InetAddress addr, int port)
		throws IOException, UnknownHostException {

	  //  Set the datagram header values

	  setMessageType ( dgramTyp);
	  setSourceName ( fromName, fromNameType);
	  setDestinationName ( toName, toNameType);
	  setSourcePort ( RFCNetBIOSProtocol.DATAGRAM);
	  setSourceIPAddress( InetAddress.getLocalHost().getAddress());
	  setFlags ( FLG_FIRSTPKT);

	  if ( m_nextId == 0)
	    m_nextId = ( int) ( System.currentTimeMillis() & 0x7FFF);
	  setDatagramId( m_nextId++);

	  //  Set the user data and length

	  setLength ( userLen + NB_USERDATA);
	  setUserData ( userData, userLen, userOff);

		//	Use the global NetBIOS datagram socket to sent the broadcast datagram
		
		NetBIOSDatagramSocket nbSocket = NetBIOSDatagramSocket.getInstance();
		nbSocket.sendDatagram(this,addr,port);
	}

	/**
	 * Send a datagram to the specified NetBIOS name using the global NetBIOS datagram socket
	 *
	 * @param dgramTyp    Datagram type
	 * @param fromName    From NetBIOS name
	 * @param fromNameType From NetBIOS name type.
	 * @param toName      To NetBIOS name
	 * @param toNameType  To NetBIOS name type.
	 * @param userData    User data buffer
	 * @param userLen     User data length.
	 * @param userOff     Offset of data within user buffer.
	 * @exception java.io.IOException		Error occurred sending datagram
	 * @exception UnknownHostException 	Failed to generate the broadcast mask for the network
	 */
	public final void SendDatagram ( int dgramTyp, String fromName, char fromNameType, String toName, char toNameType,
																	 byte[] userData, int userLen, int userOff)
		throws IOException, UnknownHostException {

	  //  Set the datagram header values

	  setMessageType ( dgramTyp);
	  setSourceName ( fromName, fromNameType);
	  setDestinationName ( toName, toNameType);
	  setSourcePort ( RFCNetBIOSProtocol.DATAGRAM);
	  setSourceIPAddress( InetAddress.getLocalHost().getAddress());
	  setFlags ( FLG_FIRSTPKT);

	  if ( m_nextId == 0)
	    m_nextId = ( int) ( System.currentTimeMillis() & 0x7FFF);
	  setDatagramId( m_nextId++);

	  //  Set the user data and length

	  setLength ( userLen + NB_USERDATA);
	  setUserData ( userData, userLen, userOff);

		//	Use the global NetBIOS datagram socket to sent the broadcast datagram
		
		NetBIOSDatagramSocket nbSocket = NetBIOSDatagramSocket.getInstance();
		nbSocket.sendBroadcastDatagram(this);
	}

	/**
	 * Send a datagram to the specified NetBIOS name using the global NetBIOS datagram socket
	 *
	 * @param dgramTyp    Datagram type
	 * @param fromName    From NetBIOS name
	 * @param toName      To NetBIOS name
	 * @param userData    User data buffer
	 * @param userLen     User data length.
	 * @exception java.io.IOException		Error occurred sending datagram
	 * @exception UnknownHostException 	Failed to generate the broadcast mask for the network
	 */
	public final void SendDatagram ( int dgramTyp, String fromName, String toName, byte[] userData, int userLen)
		throws IOException, UnknownHostException {

	  //  Send the datagram from the standard port

	  SendDatagram (dgramTyp, fromName, NetBIOSName.FileServer, toName, NetBIOSName.FileServer, userData, userLen, 0);
	}

	/**
	 * Send a datagram to the specified NetBIOS name using the supplised datagram socket.
	 *
	 * @param dgramTyp    Datagram type
	 * @param sock        Datagram socket to use to send the datagram packet.
	 * @param fromName    From NetBIOS name
	 * @param fromNameType From NetBIOS name type.
	 * @param toName      To NetBIOS name
	 * @param toNameType  To NetBIOS name type.
	 * @param userData    User data buffer
	 * @param userLen      User data length.
	 * @param userOff      Offset of data within user buffer.
	 * @exception java.io.IOException The exception description.
	 */
	public final void SendDatagram ( int dgramTyp, DatagramSocket sock, String fromName, char fromNameType, String toName,
	                 char toNameType, byte[] userData, int userLen, int userOff) throws IOException {

	  //  Set the datagram header values

	  setMessageType ( dgramTyp);
	  setSourceName ( fromName, fromNameType);
	  setDestinationName ( toName, toNameType);
	  setSourcePort ( RFCNetBIOSProtocol.DATAGRAM);
	  setSourceIPAddress( InetAddress.getLocalHost().getAddress());
	  setFlags ( FLG_FIRSTPKT);

	  if ( m_nextId == 0)
	    m_nextId = ( int) ( System.currentTimeMillis() & 0x7FFF);
	  setDatagramId( m_nextId++);

	  //  Set the user data and length

	  setLength ( userLen + NB_USERDATA);
	  setUserData ( userData, userLen, userOff);

	  //  Build a broadcast destination address

	  InetAddress destAddr = InetAddress.getByName ( NetworkSettings.GenerateBroadcastMask( null));
	  DatagramPacket dgram = new DatagramPacket ( m_buf, userLen + NB_USERDATA, destAddr, RFCNetBIOSProtocol.DATAGRAM);

	  //  Debug

	//  HexDump.Dump( m_buf, userLen + NB_USERDATA, 0);

	  //  Send the datagram

	  sock.send( dgram);
	}

	/**
	 * Send a datagram to the specified NetBIOS name using the supplied datagram socket.
	 *
	 * @param fromName java.lang.String
	 * @param toName java.lang.String
	 * @param userData byte[]
	 * @param userLen int
	 * @exception java.io.IOException The exception description.
	 */
	public final void SendDatagram ( int dgramTyp, DatagramSocket sock, String fromName, String toName,
	                 byte[] userData, int userLen) throws IOException {

	  //  Send the datagram from the standard port

	  SendDatagram (dgramTyp, sock, fromName, NetBIOSName.FileServer, toName, NetBIOSName.FileServer, userData, userLen, 0);
	}

	/**
	 * Set the datagram id.
	 *
	 * @param id int
	 */
	public final void setDatagramId ( int id) {
	  DataPacker.putIntelShort ( id, m_buf, NB_DATAGRAMID);
	}

	/**
	 * Set the datagram destination name.
	 *
	 * @param name java.lang.String
	 */
	public final void setDestinationName ( String name) {
	  setDestinationName ( name, NetBIOSName.FileServer);
	}

	/**
	 * Set the datagram destination name.
	 *
	 * @param name java.lang.String
	 */
	public final void setDestinationName ( String name, char typ) {

	  //  Convert the name to  NetBIOS RFC encoded name

	  NetBIOSSession.EncodeName ( name, typ, m_buf, NB_TONAME);
	}

	/**
	 * Set the datagram flags value.
	 *
	 * @param flg int
	 */
	public final void setFlags ( int flg) {
	  m_buf [ NB_FLAGS] = ( byte) ( flg & 0xFF);
	}

	/**
	 * Set the datagram length.
	 *
	 * @param len int
	 */
	public final void setLength(int len) {
	  DataPacker.putShort (( short) len, m_buf, NB_DATAGRAMLEN);
	}

	/**
	 * Set the NetBIOS datagram message type.
	 *
	 * @param msg int
	 */
	public final void setMessageType(int msg) {
	  m_buf [ NB_MSGTYPE] = ( byte) ( msg & 0xFF);
	}

	/**
	 * Set the source IP address for the datagram.
	 *
	 * @param ipaddr byte[]
	 */
	public final void setSourceIPAddress ( byte[] ipaddr) {

	  //  Pack the IP address into the datagram buffer

	  for ( int i = 0; i < 4; i++)
	    m_buf [ NB_SOURCEIP + i] = ipaddr [ i];
	}

	/**
	 * Set the datagram source NetBIOS name.
	 *
	 * @param name java.lang.String
	 */
	public final void setSourceName(String name) {

	  //  Convert the name to  NetBIOS RFC encoded name

	  NetBIOSSession.EncodeName ( name, NetBIOSName.FileServer, m_buf, NB_FROMNAME);
	}

	/**
	 * Set the datagram source NetBIOS name.
	 *
	 * @param name java.lang.String
	 */
	public final void setSourceName ( String name, char typ) {

	  //  Convert the name to  NetBIOS RFC encoded name

	  NetBIOSSession.EncodeName ( name, typ, m_buf, NB_FROMNAME);
	}

	/**
	 * Set the source port/socket for the datagram.
	 *
	 * @param port int
	 */
	public final void setSourcePort(int port) {
	  DataPacker.putShort(( short) port, m_buf, NB_SOURCEPORT);
	}

	/**
	 * Set the user data portion of the datagram.
	 *
	 * @param buf byte[]
	 * @param len int
	 */
	public final void setUserData ( byte[] buf, int len) {

	  //  Copy the user data

	  System.arraycopy( buf, 0, m_buf, NB_USERDATA, len)  ;
	}

	/**
	 * Set the user data portion of the datagram.
	 *
	 * @param buf   User data buffer
	 * @param len   Length of user data
	 * @param off    Offset to start of data within buffer.
	 */
	public final void setUserData ( byte[] buf, int len, int off) {

	  //  Copy the user data

	  System.arraycopy( buf, off, m_buf, NB_USERDATA, len)  ;
	}

	/**
	 * Common constructor initialization code.
	 */
	protected final void CommonInit() {
	}
}