private bool HandleMessage(byte[] buffer, int msgSize)
{
long currentTime = SystemUtils.currentTimeMillis();
if ((buffer [2] & 1) == 0)
{
if (msgSize < 7)
{
DebugLog("I msg too small!");
return(false);
}
if (firstIMessageReceived == false)
{
firstIMessageReceived = true;
lastConfirmationTime = currentTime; /* start timeout T2 */
}
int frameSendSequenceNumber = ((buffer [3] * 0x100) + (buffer [2] & 0xfe)) / 2;
int frameRecvSequenceNumber = ((buffer [5] * 0x100) + (buffer [4] & 0xfe)) / 2;
DebugLog("Received I frame: N(S) = " + frameSendSequenceNumber + " N(R) = " + frameRecvSequenceNumber);
/* check the receive sequence number N(R) - connection will be closed on an unexpected value */
if (frameSendSequenceNumber != receiveCount)
{
DebugLog("Sequence error: Close connection!");
return(false);
}
if (CheckSequenceNumber(frameRecvSequenceNumber) == false)
{
DebugLog("Sequence number check failed");
return(false);
}
receiveCount = (receiveCount + 1) % 32768;
unconfirmedReceivedIMessages++;
if (isActive)
{
try {
ASDU asdu = new ASDU(parameters, buffer, 6, msgSize);
// push to handler thread for processing
DebugLog("Enqueue received I-message for processing");
receivedASDUs.Enqueue(asdu);
}
catch (ASDUParsingException e) {
DebugLog("ASDU parsing failed: " + e.Message);
return(false);
}
}
else
{
// connection not activated --> skip message
DebugLog("Connection not activated. Skip I message");
}
}
// Check for TESTFR_ACT message
else if ((buffer [2] & 0x43) == 0x43)
{
DebugLog("Send TESTFR_CON");
socketStream.Write(TESTFR_CON_MSG, 0, TESTFR_CON_MSG.Length);
}
// Check for STARTDT_ACT message
else if ((buffer [2] & 0x07) == 0x07)
{
DebugLog("Send STARTDT_CON");
this.isActive = true;
this.server.Activated(this);
socketStream.Write(STARTDT_CON_MSG, 0, TESTFR_CON_MSG.Length);
}
// Check for STOPDT_ACT message
else if ((buffer [2] & 0x13) == 0x13)
{
DebugLog("Send STOPDT_CON");
this.isActive = false;
socketStream.Write(STOPDT_CON_MSG, 0, TESTFR_CON_MSG.Length);
}
// Check for TESTFR_CON message
else if ((buffer [2] & 0x83) == 0x83)
{
DebugLog("Recv TESTFR_CON");
outStandingTestFRConMessages = 0;
}
// S-message
else if (buffer [2] == 0x01)
{
int seqNo = (buffer[4] + buffer[5] * 0x100) / 2;
DebugLog("Recv S(" + seqNo + ") (own sendcounter = " + sendCount + ")");
if (CheckSequenceNumber(seqNo) == false)
{
return(false);
}
}
else
{
DebugLog("Unknown message");
}
ResetT3Timeout();
return(true);
}
private void HandleConnection()
{
byte[] bytes = new byte[300];
try {
try {
running = true;
if (tlsSecInfo != null)
{
DebugLog("Setup TLS");
SslStream sslStream = new SslStream(socketStream, true, RemoteCertificateValidationCallback);
bool authenticationSuccess = false;
try {
sslStream.AuthenticateAsServer(tlsSecInfo.OwnCertificate, true, System.Security.Authentication.SslProtocols.Tls, false);
if (sslStream.IsAuthenticated == true)
{
socketStream = sslStream;
authenticationSuccess = true;
}
}
catch (IOException e) {
if (e.GetBaseException() != null)
{
DebugLog("TLS authentication error: " + e.GetBaseException().Message);
}
else
{
DebugLog("TLS authentication error: " + e.Message);
}
}
if (authenticationSuccess == true)
{
socketStream = sslStream;
}
else
{
DebugLog("TLS authentication failed");
running = false;
}
}
if (running)
{
socketStream.ReadTimeout = 50;
callbackThread = new Thread(ProcessASDUs);
callbackThread.Start();
ResetT3Timeout();
}
while (running)
{
try {
// Receive the response from the remote device.
int bytesRec = receiveMessage(bytes);
if (bytesRec > 0)
{
DebugLog("RCVD: " + BitConverter.ToString(bytes, 0, bytesRec));
if (HandleMessage(bytes, bytesRec) == false)
{
/* close connection on error */
running = false;
}
if (unconfirmedReceivedIMessages >= parameters.W)
{
lastConfirmationTime = SystemUtils.currentTimeMillis();
unconfirmedReceivedIMessages = 0;
SendSMessage();
}
}
else if (bytesRec == -1)
{
running = false;
}
}
catch (System.IO.IOException) {
running = false;
}
if (handleTimeouts() == false)
{
running = false;
}
if (running)
{
if (isActive)
{
SendWaitingASDUs();
}
Thread.Sleep(1);
}
}
isActive = false;
DebugLog("CLOSE CONNECTION!");
// Release the socket.
socket.Shutdown(SocketShutdown.Both);
socket.Close();
socketStream.Dispose();
socket.Dispose();
DebugLog("CONNECTION CLOSED!");
} catch (ArgumentNullException ane) {
DebugLog("ArgumentNullException : " + ane.ToString());
} catch (SocketException se) {
DebugLog("SocketException : " + se.ToString());
} catch (Exception e) {
DebugLog("Unexpected exception : " + e.ToString());
}
} catch (Exception e) {
DebugLog(e.ToString());
}
// unmark unconfirmed messages in server queue if k-buffer not empty
if (oldestSentASDU != -1)
{
server.UnmarkAllASDUs();
}
server.Remove(this);
if (callbackThreadRunning)
{
callbackThreadRunning = false;
callbackThread.Join();
}
DebugLog("Connection thread finished");
}
private void ResetT3Timeout()
{
nextT3Timeout = (UInt64)SystemUtils.currentTimeMillis() + (UInt64)(parameters.T3 * 1000);
}
private void HandleConnection()
{
byte[] bytes = new byte[300];
try {
try {
running = true;
ResetT3Timeout();
while (running)
{
try {
// Receive the response from the remote device.
int bytesRec = receiveMessage(socket, bytes);
if (bytesRec != 0)
{
DebugLog("RCVD: " + BitConverter.ToString(bytes, 0, bytesRec));
if (HandleMessage(socket, bytes, bytesRec) == false)
{
/* close connection on error */
running = false;
}
if (unconfirmedReceivedIMessages >= parameters.W)
{
lastConfirmationTime = SystemUtils.currentTimeMillis();
unconfirmedReceivedIMessages = 0;
SendSMessage();
}
}
} catch (SocketException) {
running = false;
}
if (handleTimeouts() == false)
{
running = false;
}
if (running)
{
if (isActive)
{
SendWaitingASDUs();
}
Thread.Sleep(1);
}
}
isActive = false;
DebugLog("CLOSE CONNECTION!");
// Release the socket.
socket.Shutdown(SocketShutdown.Both);
socket.Close();
DebugLog("CONNECTION CLOSED!");
} catch (ArgumentNullException ane) {
DebugLog("ArgumentNullException : " + ane.ToString());
} catch (SocketException se) {
DebugLog("SocketException : " + se.ToString());
} catch (Exception e) {
DebugLog("Unexpected exception : " + e.ToString());
}
} catch (Exception e) {
DebugLog(e.ToString());
}
callbackThreadRunning = false;
// unmark unconfirmed messages in server queue if k-buffer not empty
if (oldestSentASDU != -1)
{
server.UnmarkAllASDUs();
}
server.Remove(this);
callbackThread.Join();
DebugLog("Connection thread finished");
}
/// <summary>
/// 信息检查，按说每收到一条信息都要来这里检查。。。
/// </summary>
/// <param name="socket"></param>
/// <param name="buffer"></param>
/// <param name="msgSize"></param>
/// <returns></returns>
private bool checkMessage(Socket socket, byte[] buffer, int msgSize)
{
//这里检测I帧和U帧，不知道为什么不检测S帧，难道是S帧已经处理过了？
//update：似乎他这里只需要发送S帧，不主动监测S帧。。。
if ((buffer[2] & 1) == 0)
{ /* I format frame */
if (debugOutput)
{
Console.WriteLine("Received I frame");
}
if (msgSize < 7)
{
if (debugOutput)
{
Console.WriteLine("I msg too small!");
}
return(false);
}
receiveCount++;
unconfirmedMessages++;
long currentTime = SystemUtils.currentTimeMillis();
if ((unconfirmedMessages > parameters.W) || checkConfirmTimeout(currentTime))
{
//未确认消息超过W，或者t2超时，则发送S帧
lastConfirmationTime = currentTime;
unconfirmedMessages = 0;
sendSMessage();
}
//新建一个ASDU，准备解析
ASDU asdu = new ASDU(parameters, buffer, msgSize);
//解析ASDU
if (asduReceivedHandler != null)
{
asduReceivedHandler(asduReceivedHandlerParameter, asdu);
}
}
else if ((buffer[2] & 0x03) == 0x03)
{ /* U format frame */
if (buffer[2] == 0x43)
{ // Check for TESTFR_ACT message
//收到了测试命令，回复测试确认
socket.Send(TESTFR_CON_MSG);
}
else if (buffer[2] == 0x07)
{ /* STARTDT ACT */
//收到了开启命令，回复开启命令确认
socket.Send(STARTDT_CON_MSG);
}
else if (buffer[2] == 0x0b)
{ /* STARTDT_CON */
//收到了开启确认，处理[已连接]事件
if (connectionHandler != null)
{
connectionHandler(connectionHandlerParameter, ConnectionEvent.STARTDT_CON_RECEIVED);
}
}
else if (buffer[2] == 0x23)
{ /* STOPDT_CON */
//收到了停止确认，处理[已断开]事件
if (connectionHandler != null)
{
connectionHandler(connectionHandlerParameter, ConnectionEvent.STOPDT_CON_RECEIVED);
}
}
}
return(true);
}
private bool checkMessage(Socket socket, byte[] buffer, int msgSize)
{
long currentTime = SystemUtils.currentTimeMillis();
if ((buffer [2] & 1) == 0) /* I format frame */
{
if (firstIMessageReceived == false)
{
firstIMessageReceived = true;
lastConfirmationTime = currentTime; /* start timeout T2 */
}
if (msgSize < 7)
{
DebugLog("I msg too small!");
return(false);
}
int frameSendSequenceNumber = ((buffer [3] * 0x100) + (buffer [2] & 0xfe)) / 2;
int frameRecvSequenceNumber = ((buffer [5] * 0x100) + (buffer [4] & 0xfe)) / 2;
DebugLog("Received I frame: N(S) = " + frameSendSequenceNumber + " N(R) = " + frameRecvSequenceNumber);
/* check the receive sequence number N(R) - connection will be closed on an unexpected value */
if (frameSendSequenceNumber != receiveSequenceNumber)
{
DebugLog("Sequence error: Close connection!");
return(false);
}
if (CheckSequenceNumber(frameRecvSequenceNumber) == false)
{
return(false);
}
receiveSequenceNumber = (receiveSequenceNumber + 1) % 32768;
unconfirmedReceivedIMessages++;
try {
ASDU asdu = new ASDU(parameters, buffer, 6, msgSize);
if (asduReceivedHandler != null)
{
asduReceivedHandler(asduReceivedHandlerParameter, asdu);
}
}
catch (ASDUParsingException e) {
DebugLog("ASDU parsing failed: " + e.Message);
return(false);
}
}
else if ((buffer [2] & 0x03) == 0x01) /* S format frame */
{
int seqNo = (buffer[4] + buffer[5] * 0x100) / 2;
DebugLog("Recv S(" + seqNo + ") (own sendcounter = " + sendSequenceNumber + ")");
if (CheckSequenceNumber(seqNo) == false)
{
return(false);
}
}
else if ((buffer [2] & 0x03) == 0x03) /* U format frame */
{
uMessageTimeout = 0;
if (buffer [2] == 0x43) // Check for TESTFR_ACT message
{
statistics.RcvdTestFrActCounter++;
DebugLog("RCVD TESTFR_ACT");
DebugLog("SEND TESTFR_CON");
socket.Send(TESTFR_CON_MSG);
statistics.SentMsgCounter++;
}
else if (buffer [2] == 0x83) /* TESTFR_CON */
{
DebugLog("RCVD TESTFR_CON");
statistics.RcvdTestFrConCounter++;
outStandingTestFRConMessages = 0;
}
else if (buffer [2] == 0x07) /* STARTDT ACT */
{
DebugLog("RCVD STARTDT_ACT");
socket.Send(STARTDT_CON_MSG);
statistics.SentMsgCounter++;
}
else if (buffer [2] == 0x0b) /* STARTDT_CON */
{
DebugLog("RCVD STARTDT_CON");
if (connectionHandler != null)
{
connectionHandler(connectionHandlerParameter, ConnectionEvent.STARTDT_CON_RECEIVED);
}
}
else if (buffer [2] == 0x23) /* STOPDT_CON */
{
DebugLog("RCVD STOPDT_CON");
if (connectionHandler != null)
{
connectionHandler(connectionHandlerParameter, ConnectionEvent.STOPDT_CON_RECEIVED);
}
}
}
else
{
DebugLog("Unknown message type");
return(false);
}
ResetT3Timeout();
return(true);
}
private void HandleConnection()
{
byte[] bytes = new byte[300];
try {
try {
connecting = true;
try {
// Connect to a remote device.
ConnectSocketWithTimeout();
DebugLog("Socket connected to " + socket.RemoteEndPoint.ToString());
if (autostart)
{
socket.Send(STARTDT_ACT_MSG);
statistics.SentMsgCounter++;
}
running = true;
socketError = false;
connecting = false;
if (connectionHandler != null)
{
connectionHandler(connectionHandlerParameter, ConnectionEvent.OPENED);
}
} catch (SocketException se) {
DebugLog("SocketException: " + se.ToString());
running = false;
socketError = true;
lastException = se;
}
if (running)
{
bool loopRunning = running;
while (loopRunning)
{
bool suspendThread = true;
try {
// Receive a message from from the remote device.
int bytesRec = receiveMessage(socket, bytes);
if (bytesRec > 0)
{
DebugLog("RCVD: " + BitConverter.ToString(bytes, 0, bytesRec));
statistics.RcvdMsgCounter++;
bool handleMessage = true;
if (rawMessageHandler != null)
{
handleMessage = rawMessageHandler(rawMessageHandlerParameter, bytes, bytesRec);
}
if (handleMessage)
{
if (checkMessage(socket, bytes, bytesRec) == false)
{
/* close connection on error */
loopRunning = false;
}
}
if (unconfirmedReceivedIMessages >= parameters.W)
{
lastConfirmationTime = SystemUtils.currentTimeMillis();
unconfirmedReceivedIMessages = 0;
SendSMessage();
}
suspendThread = false;
}
else if (bytesRec == -1)
{
loopRunning = false;
}
if (handleTimeouts() == false)
{
loopRunning = false;
}
if (isConnected() == false)
{
loopRunning = false;
}
if (useSendMessageQueue)
{
if (SendNextWaitingASDU() == true)
{
suspendThread = false;
}
}
if (suspendThread)
{
Thread.Sleep(10);
}
}
catch (SocketException) {
loopRunning = false;
}
}
DebugLog("CLOSE CONNECTION!");
// Release the socket.
try {
socket.Shutdown(SocketShutdown.Both);
}
catch (SocketException) {
}
socket.Close();
if (connectionHandler != null)
{
connectionHandler(connectionHandlerParameter, ConnectionEvent.CLOSED);
}
}
} catch (ArgumentNullException ane) {
connecting = false;
DebugLog("ArgumentNullException: " + ane.ToString());
} catch (SocketException se) {
DebugLog("SocketException: " + se.ToString());
} catch (Exception e) {
DebugLog("Unexpected exception: " + e.ToString());
}
} catch (Exception e) {
Console.WriteLine(e.ToString());
}
running = false;
connecting = false;
}
private bool handleTimeouts()
{
UInt64 currentTime = (UInt64)SystemUtils.currentTimeMillis();
if (currentTime > nextT3Timeout)
{
if (outStandingTestFRConMessages > 2)
{
DebugLog("Timeout for TESTFR_CON message");
// close connection
return(false);
}
else
{
socket.Send(TESTFR_ACT_MSG);
statistics.SentMsgCounter++;
DebugLog("U message T3 timeout");
uMessageTimeout = (UInt64)currentTime + (UInt64)(parameters.T1 * 1000);
outStandingTestFRConMessages++;
ResetT3Timeout();
if (sentMessageHandler != null)
{
sentMessageHandler(sentMessageHandlerParameter, TESTFR_ACT_MSG, 6);
}
}
}
if (unconfirmedReceivedIMessages > 0)
{
if (checkConfirmTimeout((long)currentTime))
{
lastConfirmationTime = (long)currentTime;
unconfirmedReceivedIMessages = 0;
SendSMessage(); /* send confirmation message */
}
}
if (uMessageTimeout != 0)
{
if (currentTime > uMessageTimeout)
{
DebugLog("U message T1 timeout");
throw new SocketException(10060);
}
}
/* check if counterpart confirmed I messages */
lock (sentASDUs) {
if (oldestSentASDU != -1)
{
if (((long)currentTime - sentASDUs [oldestSentASDU].sentTime) >= (parameters.T1 * 1000))
{
return(false);
}
}
}
return(true);
}