private MessageContent.SessionInitMessageContent CreateNewSession_Internal(string remoteIpAddress, string remoteHostname, int remoteHandshakePort)
{
//attempt lock
bool tryLock = lockSection.WaitOne(60000);
if (!tryLock) throw new TimeoutException("[" + _description + "-M] Could not obtain lock while creating new session]");
try
{
//check if session already exists
if (_tcpSessions.ContainsKey(remoteIpAddress))
{
_evtRaiser.RaiseEvent("SessionError", "Cannot create session: A session already exists for address [" + remoteIpAddress + "]", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
throw new Exception("[" + _description + "-M] Cannot create session: A session already exists for address [" + remoteIpAddress + "]");
}
//create a new session
TcpSession session = new TcpSession(_applicationName, _ipAddress, _portRangeMin, _portRangeMax, remoteIpAddress, remoteHostname, remoteHandshakePort, _evtConsumer, _utilsBus,_t2_SRL_ThreadStatus.NodeID);
//start the receiver
session.ReceiverStart(_applicationName + ".TcpSessionManager.CreateNewSession");
/*the session is now half-created*/
/*the remote session data will be added later when the remote makes it available*/
//get the port and return the ip and port info
MessageContent.SessionInitMessageContent initMessage = new MessageContent.SessionInitMessageContent(_ipAddress, _hostname, _handshakePort, session.LocalPort);
//initMessage.IpAddress = _ipAddress;
//initMessage.Hostname = _hostname;
//initMessage.HandshakePort = _handshakePort;
//initMessage.SessionPort = session.LocalPort;
//add session to the session list
_tcpSessions.Add(remoteIpAddress, session);
//return session initialization object
return initMessage;
}
finally
{
//release lock
lockSection.Release();
}
}
public bool ReceivedHandshakeExistingSessionValidations(TcpSession existingSession , MessageContent.HandshakeMessageContent remoteServerData)
{
//check if hostname changed
if (existingSession.RemoteHostname != remoteServerData.Hostname)
{
logger.Warn("[" + _description + "-T] Hostname changed for session [" + remoteServerData.IpAddress + "] from [" + existingSession.RemoteHostname + "] to [" + remoteServerData.Hostname + "]; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Hostname changed for session [" + remoteServerData.IpAddress + "] from [" + existingSession.RemoteHostname + "] to [" + remoteServerData.Hostname + "]; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if handshake port changed
if (existingSession.RemoteHandshakePort != remoteServerData.HandshakePort)
{
logger.Warn("[" + _description + "-T] Handshake port changed for session [" + remoteServerData.IpAddress + "] from [" + existingSession.RemoteHandshakePort + "] to [" + remoteServerData.HandshakePort + "]; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake port changed for session [" + remoteServerData.IpAddress + "] from [" + existingSession.RemoteHandshakePort + "] to [" + remoteServerData.HandshakePort + "]; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session initialization is complete
if (!existingSession.IsSessionInitReceived || !existingSession.IsSessionInitSent)
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where initialization never completed; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where initialization never completed; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session contains message transmitter errors
if (existingSession.Transmitter != null && existingSession.Transmitter.ThreadStatus.MessageErrorCount > 0)
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where there are message transmitter errors; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where there are message transmitter errors; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session contains message receiver errors
if (existingSession.Receiver != null && existingSession.Receiver.ThreadStatus.MessageErrorCount > 0)
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where there are message receiver errors; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where there are message receiver errors; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session validations valid
if (existingSession.SessionValidationFailedDate > DateTime.MinValue)
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where session integrity validations failed; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where session integrity validations failed; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session transmitter thread health failed
if (existingSession.Transmitter != null && existingSession.Transmitter.ThreadStatus.CalculateThreadHealthFailed())
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where session transmitter thread health failed; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where session transmitter thread health failed; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session receiver thread health failed
if (existingSession.Receiver != null && existingSession.Receiver.ThreadStatus.CalculateThreadHealthFailed())
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where session receiver thread health failed; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where session receiver thread health failed; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session transmitter status is non-active
if (existingSession.Transmitter != null && (existingSession.Transmitter.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_STOPPED ||
existingSession.Transmitter.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_SUSPENDED ||
existingSession.Transmitter.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_UNKNOWN ||
existingSession.Transmitter.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_FINALIZED))
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where session transmitter status is non-active; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where session transmitter status is non-active; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
//check if session receiver status is non-active
if (existingSession.Receiver != null && (existingSession.Receiver .ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_STOPPED ||
existingSession.Receiver.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_SUSPENDED ||
existingSession.Receiver.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_UNKNOWN ||
existingSession.Receiver.ThreadStatus.Status == Niawa.Threading.ThreadStatus.STATUS_FINALIZED))
{
logger.Warn("[" + _description + "-T] Handshake message received for session [" + remoteServerData.IpAddress + "] where session receiver status is non-active; invalidating existing session");
_evtRaiser.RaiseEvent("SessionError", "UdpReceiverListener: Handshake message received for session [" + remoteServerData.IpAddress + "] where session receiver status is non-active; invalidating existing session", null, _threadStatus.NodeID, _threadStatus.ParentNodeID);
return true;
}
return false;
}
/// <summary>
/// Execute session validation checks.
/// This may result in a session being removed
/// </summary>
/// <param name="session"></param>
private bool SessionValidationChecks(TcpSession session, string remoteIpAddress)
{
try
{
/* -----------------------------------------------------------------------------*/
/* Session validity check: Session initialization not received after 60 seconds */
if (session.SessionValidationFailedDate == DateTime.MinValue && !session.IsSessionInitReceived)
{
if (session.ThreadStatus.InitializedDate != DateTime.MinValue)
{
TimeSpan timespan = (DateTime.Now - session.ThreadStatus.InitializedDate);
double timePassed = 0;
timePassed = timespan.TotalSeconds + 0.01;
if (timePassed > 60)
{
//validation failed
session.SessionValidationFailedDate = DateTime.Now;
//validation failed - remove the session
logger.Warn("[" + _description + "-TSRL] Session [" + remoteIpAddress + "] validation failed: session initialization has not been received for 60 seconds");
_evtRaiser.RaiseEvent("SessionError", "Session [" + remoteIpAddress + "] validation failed: session initialization has not been received for 60 seconds", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
}
}
else
{
//session initialization date isn't valid
}
}
/* -----------------------------------------------------------------------------*/
/* Session validity check: Transmitter is null after 60 seconds */
if (session.SessionValidationFailedDate == DateTime.MinValue && session.Transmitter == null)
{
if (session.ThreadStatus.InitializedDate != DateTime.MinValue)
{
TimeSpan timespan = (DateTime.Now - session.ThreadStatus.InitializedDate);
double timePassed = 0;
timePassed = timespan.TotalSeconds + 0.01;
if (timePassed > 60)
{
//validation failed
session.SessionValidationFailedDate = DateTime.Now;
//validation failed - remove the session
logger.Warn("[" + _description + "-TSRL] Session [" + remoteIpAddress + "] validation failed: session transmitter is null after 60 seconds");
_evtRaiser.RaiseEvent("SessionError", "Session [" + remoteIpAddress + "] validation failed: session transmitter is null after 60 seconds", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
}
}
else
{
//session initialization date isn't valid
}
}
/* -----------------------------------------------------------------------------*/
/* Session validity check: Transmitter message error count > 0 */
if (session.SessionValidationFailedDate == DateTime.MinValue && session.Transmitter != null && session.Transmitter.ThreadStatus.MessageErrorCount > 0)
{
if (session.ThreadStatus.InitializedDate != DateTime.MinValue)
{
TimeSpan timespan = (DateTime.Now - session.ThreadStatus.InitializedDate);
double timePassed = 0;
timePassed = timespan.TotalSeconds + 0.01;
if (timePassed > 60)
{
//validation failed
session.SessionValidationFailedDate = DateTime.Now;
//validation failed - remove the session
logger.Warn("[" + _description + "-TSRL] Session [" + remoteIpAddress + "] validation failed: transmitter error count is greater than zero");
_evtRaiser.RaiseEvent("SessionError", "Session [" + remoteIpAddress + "] validation failed: transmitter error count is greater than zero", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
}
}
else
{
//session initialization date isn't valid
}
}
/* -----------------------------------------------------------------------------*/
/* Session validity check: Receiver is null after 60 seconds */
if (session.SessionValidationFailedDate == DateTime.MinValue && session.Receiver == null)
{
if (session.ThreadStatus.InitializedDate != DateTime.MinValue)
{
TimeSpan timespan = (DateTime.Now - session.ThreadStatus.InitializedDate);
double timePassed = 0;
timePassed = timespan.TotalSeconds + 0.01;
if (timePassed > 60)
{
//validation failed
session.SessionValidationFailedDate = DateTime.Now;
//validation failed - remove the session
logger.Warn("[" + _description + "-TSRL] Session [" + remoteIpAddress + "] validation failed: session receiver is null after 60 seconds");
_evtRaiser.RaiseEvent("SessionError", "Session [" + remoteIpAddress + "] validation failed: session receiver is null after 60 seconds", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
}
}
else
{
//session initialization date isn't valid
}
}
/* -----------------------------------------------------------------------------*/
/* Session validity check: Transmitter message error count > 0 */
if (session.SessionValidationFailedDate == DateTime.MinValue && session.Receiver != null && session.Receiver.ThreadStatus.MessageErrorCount > 0)
{
if (session.ThreadStatus.InitializedDate != DateTime.MinValue)
{
TimeSpan timespan = (DateTime.Now - session.ThreadStatus.InitializedDate);
double timePassed = 0;
timePassed = timespan.TotalSeconds + 0.01;
if (timePassed > 60)
{
//validation failed
session.SessionValidationFailedDate = DateTime.Now;
//validation failed - remove the session
logger.Warn("[" + _description + "-TSRL] Session [" + remoteIpAddress + "] validation failed: receiver error count is greater than zero");
_evtRaiser.RaiseEvent("SessionError", "Session [" + remoteIpAddress + "] validation failed: receiver error count is greater than zero", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
}
}
else
{
//session initialization date isn't valid
}
}
/****************************************************************************/
/* If 90 seconds passed since last session validity check, remove the session*/
if (session.SessionValidationFailedDate > DateTime.MinValue)
{
TimeSpan timespan = (DateTime.Now - session.SessionValidationFailedDate);
double timePassed = 0;
timePassed = timespan.TotalSeconds + 0.01;
if (timePassed > 90)
{
//validation failed - remove the session
logger.Warn("[" + _description + "-TSRL] Session [" + remoteIpAddress + "] integrity validations failed for 90 seconds; removing invalidated session");
_evtRaiser.RaiseEvent("SessionError", "Session [" + remoteIpAddress + "] integrity validations failed for 90 seconds; removing invalidated session", null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
//remove session
//RemoveSession(remoteIpAddress, true);
return true;
}
}
return false;
}
catch (Exception ex)
{
logger.Error("[" + _description + "-TSRL] Error while executing session validation checks: " + ex.Message + "]", ex);
_evtRaiser.RaiseEvent("Error", "Error while executing session validation checks: " + ex.Message, null, _t2_SRL_ThreadStatus.NodeID, _t2_SRL_ThreadStatus.ParentNodeID);
_t2_SRL_ThreadStatus.ErrorCount += 1;
return false;
}
}