/*
* Conditions Of Use
*
* This software was developed by employees of the National Institute of
* Standards and Technology (NIST), an agency of the Federal Government.
* Pursuant to title 15 Untied States Code Section 105, works of NIST
* employees are not subject to copyright protection in the United States
* and are considered to be in the public domain. As a result, a formal
* license is not needed to use the software.
*
* This software is provided by NIST as a service and is expressly
* provided "AS IS." NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
* OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
* AND DATA ACCURACY. NIST does not warrant or make any representations
* regarding the use of the software or the results thereof, including but
* not limited to the correctness, accuracy, reliability or usefulness of
* the software.
*
* Permission to use this software is contingent upon your acceptance
* of the terms of this agreement
*
* .
*
*/
/*****************************************************************************
* Product of NIST/ITL Advanced Networking Technologies Division (ANTD). *
*****************************************************************************/
package gov.nist.javax.sip.stack;
import java.net.*;
import gov.nist.javax.sip.*;
import gov.nist.core.*;
import gov.nist.javax.sip.header.*;
import gov.nist.javax.sip.parser.*;
import gov.nist.javax.sip.message.*;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.String;
import java.text.ParseException;
import javax.sip.address.Hop;
import javax.sip.header.CSeqHeader;
import javax.sip.header.CallIdHeader;
import javax.sip.header.ContentTypeHeader;
import javax.sip.header.FromHeader;
import javax.sip.header.ToHeader;
import javax.sip.header.ViaHeader;
import javax.sip.message.Request;
import javax.sip.message.Response;
/*
* Kim Kirby (Keyvoice) suggested that duplicate checking should be added to the
* stack (later removed). Lamine Brahimi suggested a single threaded behavior
* flag be added to this. Niklas Uhrberg suggested that thread pooling support
* be added to this for performance and resource management. Peter Parnes found
* a bug with this code that was sending it into an infinite loop when a bad
* incoming message was parsed. Bug fix by viswashanti.kadiyala@antepo.com.
* Hagai Sela addded fixes for NAT traversal. Jeroen van Bemmel fixed up for
* buggy clients (such as windows messenger) and added code to return
* BAD_REQUEST. David Alique fixed an address recording bug. Jeroen van Bemmel
* fixed a performance issue where the stack was doing DNS lookups (potentially
* unnecessary). Ricardo Bora (Natural Convergence ) added code that prevents
* the stack from exitting when an exception is encountered.
*
*/
/**
* This is the UDP Message handler that gets created when a UDP message needs to
* be processed. The message is processed by creating a String Message parser
* and invoking it on the message read from the UDP socket. The parsed structure
* is handed off via a SIP stack request for further processing. This stack
* structure isolates the message handling logic from the mechanics of sending
* and recieving messages (which could be either udp or tcp.
*
*
* @author M. Ranganathan <br/>
*
*
*
* @version 1.2 $Revision: 1.57 $ $Date: 2009/05/30 04:22:00 $
*/
public class UDPMessageChannel extends MessageChannel implements
ParseExceptionListener, Runnable, RawMessageChannel {
/**
* SIP Stack structure for this channel.
*/
protected SIPTransactionStack sipStack;
/**
* The parser we are using for messages received from this channel.
*/
protected StringMsgParser myParser;
/**
* Where we got the stuff from
*/
private InetAddress peerAddress;
private String myAddress;
private int peerPacketSourcePort;
private InetAddress peerPacketSourceAddress;
/**
* Reciever port -- port of the destination.
*/
private int peerPort;
/**
* Protocol to use when talking to receiver (i.e. when sending replies).
*/
private String peerProtocol;
protected int myPort;
private DatagramPacket incomingPacket;
private long receptionTime;
/**
* Constructor - takes a datagram packet and a stack structure Extracts the
* address of the other from the datagram packet and stashes away the
* pointer to the passed stack structure.
*
* @param stack
* is the shared SIPStack structure
* @param messageProcessor
* is the creating message processor.
*/
protected UDPMessageChannel(SIPTransactionStack stack,
UDPMessageProcessor messageProcessor) {
super.messageProcessor = messageProcessor;
this.sipStack = stack;
Thread mythread = new Thread(this);
this.myAddress = messageProcessor.getIpAddress().getHostAddress();
this.myPort = messageProcessor.getPort();
mythread.setName("UDPMessageChannelThread");
mythread.setDaemon(true);
mythread.start();
}
/**
* Constructor. We create one of these in order to process an incoming
* message.
*
* @param stack
* is the SIP sipStack.
* @param messageProcessor
* is the creating message processor.
* @param packet
* is the incoming datagram packet.
*/
protected UDPMessageChannel(SIPTransactionStack stack,
UDPMessageProcessor messageProcessor, DatagramPacket packet) {
this.incomingPacket = packet;
super.messageProcessor = messageProcessor;
this.sipStack = stack;
this.myAddress = messageProcessor.getIpAddress().getHostAddress();
this.myPort = messageProcessor.getPort();
Thread mythread = new Thread(this);
mythread.setDaemon(true);
mythread.start();
}
/**
* Constructor. We create one of these when we send out a message.
*
* @param targetAddr
* INET address of the place where we want to send messages.
* @param port
* target port (where we want to send the message).
* @param sipStack
* our SIP Stack.
*/
protected UDPMessageChannel(InetAddress targetAddr, int port,
SIPTransactionStack sipStack, UDPMessageProcessor messageProcessor) {
peerAddress = targetAddr;
peerPort = port;
peerProtocol = "UDP";
super.messageProcessor = messageProcessor;
this.myAddress = messageProcessor.getIpAddress().getHostAddress();
this.myPort = messageProcessor.getPort();
this.sipStack = sipStack;
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug("Creating message channel "
+ targetAddr.getHostAddress() + "/" + port);
}
}
/**
* Run method specified by runnnable.
*/
public void run() {
// Assume no thread pooling (bug fix by spierhj)
ThreadAuditor.ThreadHandle threadHandle = null;
while (true) {
// Create a new string message parser to parse the list of messages.
if (myParser == null) {
myParser = new StringMsgParser();
myParser.setParseExceptionListener(this);
}
// messages that we write out to him.
DatagramPacket packet;
if (sipStack.threadPoolSize != -1) {
synchronized (((UDPMessageProcessor) messageProcessor).messageQueue) {
while (((UDPMessageProcessor) messageProcessor).messageQueue
.isEmpty()) {
// Check to see if we need to exit.
if (!((UDPMessageProcessor) messageProcessor).isRunning)
return;
try {
// We're part of a thread pool. Ask the auditor to
// monitor this thread.
if (threadHandle == null) {
threadHandle = sipStack.getThreadAuditor()
.addCurrentThread();
}
// Send a heartbeat to the thread auditor
threadHandle.ping();
// Wait for packets
// Note: getPingInterval returns 0 (infinite) if the
// thread auditor is disabled.
((UDPMessageProcessor) messageProcessor).messageQueue
.wait(threadHandle
.getPingIntervalInMillisecs());
} catch (InterruptedException ex) {
if (!((UDPMessageProcessor) messageProcessor).isRunning)
return;
}
}
packet = (DatagramPacket) ((UDPMessageProcessor) messageProcessor).messageQueue
.removeFirst();
}
this.incomingPacket = packet;
} else {
packet = this.incomingPacket;
}
// Process the packet. Catch and log any exception we may throw.
try {
processIncomingDataPacket(packet);
} catch (Exception e) {
sipStack.logWriter.logError(
"Error while processing incoming UDP packet", e);
}
if (sipStack.threadPoolSize == -1) {
return;
}
}
}
/**
* Process an incoming datagram
*
* @param packet
* is the incoming datagram packet.
*/
private void processIncomingDataPacket(DatagramPacket packet)
throws Exception {
this.peerAddress = packet.getAddress();
int packetLength = packet.getLength();
// Read bytes and put it in a eueue.
byte[] bytes = packet.getData();
byte[] msgBytes = new byte[packetLength];
System.arraycopy(bytes, 0, msgBytes, 0, packetLength);
// Do debug logging.
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter
.logDebug("UDPMessageChannel: processIncomingDataPacket : peerAddress = "
+ peerAddress.getHostAddress() + "/"
+ packet.getPort() + " Length = " + packetLength);
}
SIPMessage sipMessage = null;
try {
this.receptionTime = System.currentTimeMillis();
sipMessage = myParser.parseSIPMessage(msgBytes);
myParser = null;
} catch (ParseException ex) {
myParser = null; // let go of the parser reference.
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug("Rejecting message ! "
+ new String(msgBytes));
this.sipStack.logWriter.logDebug("error message "
+ ex.getMessage());
this.sipStack.logWriter.logException(ex);
}
// JvB: send a 400 response for requests (except ACK)
// Currently only UDP, @todo also other transports
String msgString = new String(msgBytes, 0, packetLength);
if (!msgString.startsWith("SIP/") && !msgString.startsWith("ACK ")) {
String badReqRes = createBadReqRes(msgString, ex);
if (badReqRes != null) {
if (sipStack.isLoggingEnabled()) {
sipStack.getLogWriter().logDebug(
"Sending automatic 400 Bad Request:");
sipStack.getLogWriter().logDebug(badReqRes);
}
try {
this.sendMessage(badReqRes.getBytes(), peerAddress,
packet.getPort(), "UDP", false);
} catch (IOException e) {
this.sipStack.logWriter.logException(e);
}
} else {
if (sipStack.isLoggingEnabled()) {
sipStack
.getLogWriter()
.logDebug(
"Could not formulate automatic 400 Bad Request");
}
}
}
return;
}
// No parse exception but null message - reject it and
// march on (or return).
// exit this message processor if the message did not parse.
if (sipMessage == null) {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug("Rejecting message ! + Null message parsed.");
}
return;
}
ViaList viaList = sipMessage.getViaHeaders();
// Check for the required headers.
if (sipMessage.getFrom() == null || sipMessage.getTo() == null
|| sipMessage.getCallId() == null
|| sipMessage.getCSeq() == null
|| sipMessage.getViaHeaders() == null) {
String badmsg = new String(msgBytes);
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logError("bad message " + badmsg);
this.sipStack.logWriter.logError(">>> Dropped Bad Msg "
+ "From = " + sipMessage.getFrom() + "To = "
+ sipMessage.getTo() + "CallId = "
+ sipMessage.getCallId() + "CSeq = "
+ sipMessage.getCSeq() + "Via = "
+ sipMessage.getViaHeaders());
}
sipStack.logWriter.logError("BAD MESSAGE!");
return;
}
// For a request first via header tells where the message
// is coming from.
// For response, just get the port from the packet.
if (sipMessage instanceof SIPRequest) {
Via v = (Via) viaList.getFirst();
Hop hop = sipStack.addressResolver.resolveAddress(v.getHop());
this.peerPort = hop.getPort();
this.peerProtocol = v.getTransport();
this.peerPacketSourceAddress = packet.getAddress();
this.peerPacketSourcePort = packet.getPort();
try {
this.peerAddress = packet.getAddress();
// Check to see if the received parameter matches
// the peer address and tag it appropriately.
boolean hasRPort = v.hasParameter(Via.RPORT);
if (hasRPort
|| !hop.getHost().equals(
this.peerAddress.getHostAddress())) {
v.setParameter(Via.RECEIVED, this.peerAddress
.getHostAddress());
}
if (hasRPort) {
v.setParameter(Via.RPORT, Integer
.toString(this.peerPacketSourcePort));
}
} catch (java.text.ParseException ex1) {
InternalErrorHandler.handleException(ex1);
}
} else {
this.peerPacketSourceAddress = packet.getAddress();
this.peerPacketSourcePort = packet.getPort();
this.peerAddress = packet.getAddress();
this.peerPort = packet.getPort();
this.peerProtocol = ((Via) viaList.getFirst()).getTransport();
}
this.processMessage(sipMessage);
}
/**
* Actually proces the parsed message.
*
* @param sipMessage
*/
public void processMessage(SIPMessage sipMessage) {
if (sipMessage instanceof SIPRequest) {
SIPRequest sipRequest = (SIPRequest) sipMessage;
// This is a request - process it.
// So far so good -- we will commit this message if
// all processing is OK.
if (sipStack.logWriter.isLoggingEnabled(ServerLog.TRACE_MESSAGES)) {
this.sipStack.serverLog.logMessage(sipMessage, this
.getPeerHostPort().toString(), this.getHost() + ":"
+ this.myPort, false, receptionTime);
}
ServerRequestInterface sipServerRequest = sipStack
.newSIPServerRequest(sipRequest, this);
// Drop it if there is no request returned
if (sipServerRequest == null) {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter
.logWarning("Null request interface returned -- dropping request");
}
return;
}
if (sipStack.isLoggingEnabled())
this.sipStack.logWriter.logDebug("About to process "
+ sipRequest.getFirstLine() + "/" + sipServerRequest);
try {
sipServerRequest.processRequest(sipRequest, this);
} finally {
if (sipServerRequest instanceof SIPTransaction) {
SIPServerTransaction sipServerTx = (SIPServerTransaction) sipServerRequest;
if (!sipServerTx.passToListener()) {
((SIPTransaction) sipServerRequest).releaseSem();
}
}
}
if (sipStack.isLoggingEnabled())
this.sipStack.logWriter.logDebug("Done processing "
+ sipRequest.getFirstLine() + "/" + sipServerRequest);
// So far so good -- we will commit this message if
// all processing is OK.
} else {
// Handle a SIP Reply message.
SIPResponse sipResponse = (SIPResponse) sipMessage;
try {
sipResponse.checkHeaders();
} catch (ParseException ex) {
if (sipStack.isLoggingEnabled())
sipStack.logWriter
.logError("Dropping Badly formatted response message >>> "
+ sipResponse);
return;
}
ServerResponseInterface sipServerResponse = sipStack
.newSIPServerResponse(sipResponse, this);
if (sipServerResponse != null) {
try {
if (sipServerResponse instanceof SIPClientTransaction
&& !((SIPClientTransaction) sipServerResponse)
.checkFromTag(sipResponse)) {
if (sipStack.isLoggingEnabled())
sipStack.logWriter
.logError("Dropping response message with invalid tag >>> "
+ sipResponse);
return;
}
sipServerResponse.processResponse(sipResponse, this);
} finally {
if (sipServerResponse instanceof SIPTransaction
&& !((SIPTransaction) sipServerResponse)
.passToListener())
((SIPTransaction) sipServerResponse).releaseSem();
}
// Normal processing of message.
} else {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug("null sipServerResponse!");
}
}
}
}
/**
* JvB: added method to check for known buggy clients (Windows Messenger) to
* fix the port to which responses are sent
*
* checks for User-Agent: RTC/1.3.5470 (Messenger 5.1.0701)
*
* JvB 22/7/2006 better to take this out for the moment, it is only a
* problem in rare cases (unregister)
*
* private final boolean isBuggyClient( SIPRequest r ) { UserAgent uah =
* (UserAgent) r.getHeader( UserAgent.NAME ); if (uah!=null) {
* java.util.ListIterator i = uah.getProduct(); if (i.hasNext()) { String p =
* (String) uah.getProduct().next(); return p.startsWith( "RTC" ); } }
* return false; }
*/
/**
* Implementation of the ParseExceptionListener interface.
*
* @param ex
* Exception that is given to us by the parser.
* @throws ParseException
* If we choose to reject the header or message.
*/
public void handleException(ParseException ex, SIPMessage sipMessage,
Class hdrClass, String header, String message)
throws ParseException {
if (sipStack.isLoggingEnabled())
this.sipStack.logWriter.logException(ex);
// Log the bad message for later reference.
if ((hdrClass != null)
&& (hdrClass.equals(From.class) || hdrClass.equals(To.class)
|| hdrClass.equals(CSeq.class)
|| hdrClass.equals(Via.class)
|| hdrClass.equals(CallID.class)
|| hdrClass.equals(RequestLine.class) || hdrClass
.equals(StatusLine.class))) {
sipStack.logWriter.logError("BAD MESSAGE!");
sipStack.logWriter.logError(message);
throw ex;
} else {
sipMessage.addUnparsed(header);
}
}
/**
* Return a reply from a pre-constructed reply. This sends the message back
* to the entity who caused us to create this channel in the first place.
*
* @param sipMessage
* Message string to send.
* @throws IOException
* If there is a problem with sending the message.
*/
public void sendMessage(SIPMessage sipMessage) throws IOException {
if (sipStack.isLoggingEnabled() && this.sipStack.logStackTraceOnMessageSend) {
if ( sipMessage instanceof SIPRequest &&
((SIPRequest)sipMessage).getRequestLine() != null) {
/*
* We dont want to log empty trace messages.
*/
this.sipStack.logWriter.logStackTrace(LogWriter.TRACE_MESSAGES);
} else {
this.sipStack.logWriter.logStackTrace(LogWriter.TRACE_MESSAGES);
}
}
// Test and see where we are going to send the messsage. If the message
// is sent back to oursleves, just
// shortcircuit processing.
long time = System.currentTimeMillis();
try {
for (MessageProcessor messageProcessor : sipStack
.getMessageProcessors()) {
if (messageProcessor.getIpAddress().equals(this.peerAddress)
&& messageProcessor.getPort() == this.peerPort
&& messageProcessor.getTransport().equals(
this.peerProtocol)) {
MessageChannel messageChannel = messageProcessor
.createMessageChannel(this.peerAddress,
this.peerPort);
if (messageChannel instanceof RawMessageChannel) {
((RawMessageChannel) messageChannel)
.processMessage(sipMessage);
sipStack.logWriter.logDebug("Self routing message");
return;
}
}
}
byte[] msg = sipMessage.encodeAsBytes( this.getTransport() );
sendMessage(msg, peerAddress, peerPort, peerProtocol,
sipMessage instanceof SIPRequest);
} catch (IOException ex) {
throw ex;
} catch (Exception ex) {
sipStack.logWriter.logError("An exception occured while sending message",ex);
throw new IOException(
"An exception occured while sending message");
} finally {
if (sipStack.logWriter.isLoggingEnabled(ServerLog.TRACE_MESSAGES))
logMessage(sipMessage, peerAddress, peerPort, time);
}
}
/**
* Send a message to a specified receiver address.
*
* @param msg
* string to send.
* @param peerAddress
* Address of the place to send it to.
* @param peerPort
* the port to send it to.
* @throws IOException
* If there is trouble sending this message.
*/
protected void sendMessage(byte[] msg, InetAddress peerAddress,
int peerPort, boolean reConnect) throws IOException {
// Via is not included in the request so silently drop the reply.
if (sipStack.isLoggingEnabled() && this.sipStack.logStackTraceOnMessageSend ) {
this.sipStack.logWriter.logStackTrace(LogWriter.TRACE_MESSAGES);
}
if (peerPort == -1) {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug(getClass().getName()
+ ":sendMessage: Dropping reply!");
}
throw new IOException("Receiver port not set ");
} else {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug("sendMessage " + peerAddress.getHostAddress() + "/"
+ peerPort + "\n" + "messageSize = " + msg.length + " message = " + new String(msg)) ;
this.sipStack.logWriter.logDebug("*******************\n");
}
}
DatagramPacket reply = new DatagramPacket(msg, msg.length, peerAddress,
peerPort);
try {
DatagramSocket sock;
boolean created = false;
if (sipStack.udpFlag) {
// Use the socket from the message processor (for firewall
// support use the same socket as the message processor
// socket -- feature request # 18 from java.net). This also
// makes the whole thing run faster!
sock = ((UDPMessageProcessor) messageProcessor).sock;
// Bind the socket to the stack address in case there
// are multiple interfaces on the machine (feature reqeust
// by Will Scullin) 0 binds to an ephemeral port.
// sock = new DatagramSocket(0,sipStack.stackInetAddress);
} else {
// bind to any interface and port.
sock = new DatagramSocket();
created = true;
}
sock.send(reply);
if (created)
sock.close();
} catch (IOException ex) {
throw ex;
} catch (Exception ex) {
InternalErrorHandler.handleException(ex);
}
}
/**
* Send a message to a specified receiver address.
*
* @param msg
* message string to send.
* @param peerAddress
* Address of the place to send it to.
* @param peerPort
* the port to send it to.
* @param peerProtocol
* protocol to use to send.
* @throws IOException
* If there is trouble sending this message.
*/
protected void sendMessage(byte[] msg, InetAddress peerAddress,
int peerPort, String peerProtocol, boolean retry)
throws IOException {
// Via is not included in the request so silently drop the reply.
if (peerPort == -1) {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug(getClass().getName()
+ ":sendMessage: Dropping reply!");
}
throw new IOException("Receiver port not set ");
} else {
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug( ":sendMessage " + peerAddress.getHostAddress() + "/"
+ peerPort + "\n" + " messageSize = " + msg.length
+ "\n message = "+ new String(msg));
this.sipStack.logWriter.logDebug("*******************\n");
}
}
if (peerProtocol.compareToIgnoreCase("UDP") == 0) {
DatagramPacket reply = new DatagramPacket(msg, msg.length,
peerAddress, peerPort);
try {
DatagramSocket sock;
if (sipStack.udpFlag) {
sock = ((UDPMessageProcessor) messageProcessor).sock;
} else {
// bind to any interface and port.
sock = sipStack.getNetworkLayer().createDatagramSocket();
}
if (sipStack.isLoggingEnabled()) {
this.sipStack.logWriter.logDebug("sendMessage "
+ peerAddress.getHostAddress() + "/" + peerPort
+ "\n" + new String(msg));
}
sock.send(reply);
if (!sipStack.udpFlag)
sock.close();
} catch (IOException ex) {
throw ex;
} catch (Exception ex) {
InternalErrorHandler.handleException(ex);
}
} else {
// Use TCP to talk back to the sender.
Socket outputSocket = sipStack.ioHandler.sendBytes(
this.messageProcessor.getIpAddress(), peerAddress,
peerPort, "tcp", msg, retry);
OutputStream myOutputStream = outputSocket.getOutputStream();
myOutputStream.write(msg, 0, msg.length);
myOutputStream.flush();
// The socket is cached (dont close it!);
}
}
/**
* get the stack pointer.
*
* @return The sip stack for this channel.
*/
public SIPTransactionStack getSIPStack() {
return sipStack;
}
/**
* Return a transport string.
*
* @return the string "udp" in this case.
*/
public String getTransport() {
return SIPConstants.UDP;
}
/**
* get the stack address for the stack that received this message.
*
* @return The stack address for our sipStack.
*/
public String getHost() {
return messageProcessor.getIpAddress().getHostAddress();
}
/**
* get the port.
*
* @return Our port (on which we are getting datagram packets).
*/
public int getPort() {
return ((UDPMessageProcessor) messageProcessor).getPort();
}
/**
* get the name (address) of the host that sent me the message
*
* @return The name of the sender (from the datagram packet).
*/
public String getPeerName() {
return peerAddress.getHostName();
}
/**
* get the address of the host that sent me the message
*
* @return The senders ip address.
*/
public String getPeerAddress() {
return peerAddress.getHostAddress();
}
protected InetAddress getPeerInetAddress() {
return peerAddress;
}
/**
* Compare two UDP Message channels for equality.
*
* @param other
* The other message channel with which to compare oursleves.
*/
public boolean equals(Object other) {
if (other == null)
return false;
boolean retval;
if (!this.getClass().equals(other.getClass())) {
retval = false;
} else {
UDPMessageChannel that = (UDPMessageChannel) other;
retval = this.getKey().equals(that.getKey());
}
return retval;
}
public String getKey() {
return getKey(peerAddress, peerPort, "UDP");
}
public int getPeerPacketSourcePort() {
return peerPacketSourcePort;
}
public InetAddress getPeerPacketSourceAddress() {
return peerPacketSourceAddress;
}
/**
* Get the logical originator of the message (from the top via header).
*
* @return topmost via header sentby field
*/
public String getViaHost() {
return this.myAddress;
}
/**
* Get the logical port of the message orginator (from the top via hdr).
*
* @return the via port from the topmost via header.
*/
public int getViaPort() {
return this.myPort;
}
/**
* Returns "false" as this is an unreliable transport.
*/
public boolean isReliable() {
return false;
}
/**
* UDP is not a secure protocol.
*/
public boolean isSecure() {
return false;
}
public int getPeerPort() {
return peerPort;
}
public String getPeerProtocol() {
return this.peerProtocol;
}
/**
* Close the message channel.
*/
public void close() {
}
}