/// <summary>
/// Handles a packet, reading the flags and processing all fragments.
/// </summary>
/// <param name="packet">ClientPacket to handle</param>
private void HandlePacket(ClientPacket packet)
{
log.DebugFormat("[{0}] Handling packet {1}", session.LoggingIdentifier, packet.Header.Sequence);
uint issacXor = packet.Header.HasFlag(PacketHeaderFlags.EncryptedChecksum) ? ConnectionData.IssacClient.GetOffset() : 0;
if (!packet.VerifyChecksum(issacXor))
{
log.WarnFormat("[{0}] Packet {1} has invalid checksum", session.LoggingIdentifier, packet.Header.Sequence);
}
// depending on the current session state:
// Set the next timeout tick value, to compare against in the WorldManager
// Sessions that have gone past the AuthLoginRequest step will stay active for a longer period of time (exposed via configuration)
// Sessions that in the AuthLoginRequest will have a short timeout, as set in the AuthenticationHandler.DefaultAuthTimeout.
// Example: Applications that check uptime will stay in the AuthLoginRequest state.
session.Network.TimeoutTick = (session.State == Enum.SessionState.AuthLoginRequest) ?
DateTime.UtcNow.AddSeconds(WorldManager.DefaultSessionTimeout).Ticks :
DateTime.UtcNow.AddSeconds(AuthenticationHandler.DefaultAuthTimeout).Ticks;
// If we have an EchoRequest flag, we should flag to respond with an echo response on next send.
if (packet.Header.HasFlag(PacketHeaderFlags.EchoRequest))
{
FlagEcho(packet.HeaderOptional.EchoRequestClientTime);
}
// If we have an AcknowledgeSequence flag, we can clear our cached packet buffer up to that sequence.
if (packet.Header.HasFlag(PacketHeaderFlags.AckSequence))
{
AcknowledgeSequence(packet.HeaderOptional.Sequence);
}
if (packet.Header.HasFlag(PacketHeaderFlags.TimeSynch))
{
log.DebugFormat("[{0}] Incoming TimeSync TS: {1}", session.LoggingIdentifier, packet.HeaderOptional.TimeSynch);
// Do something with this...
// Based on network traces these are not 1:1. Server seems to send them every 20 seconds per port.
// Client seems to send them alternatingly every 2 or 4 seconds per port.
// We will send this at a 20 second time interval. I don't know what to do with these when we receive them at this point.
}
// If the client is requesting a retransmission, pull those packets from the queue and resend them.
if (packet.Header.HasFlag(PacketHeaderFlags.RequestRetransmit))
{
foreach (uint sequence in packet.HeaderOptional.RetransmitData)
{
Retransmit(sequence);
}
}
// This should be set on the first packet to the server indicating the client is logging in.
// This is the start of a three-way handshake between the client and server (LoginRequest, ConnectRequest, ConnectResponse)
// Note this would be sent to each server a client would connect too (Login and each world).
// In our current implimenation we handle all roles in this one server.
if (packet.Header.HasFlag(PacketHeaderFlags.LoginRequest))
{
log.Info($"[{session.LoggingIdentifier}] LoginRequest");
AuthenticationHandler.HandleLoginRequest(packet, session);
return;
}
// This should be set on the second packet to the server from the client.
// This completes the three-way handshake.
if (packet.Header.HasFlag(PacketHeaderFlags.ConnectResponse))
{
sendResync = true;
AuthenticationHandler.HandleConnectResponse(packet, session);
return;
}
// Process all fragments out of the packet
foreach (ClientPacketFragment fragment in packet.Fragments)
{
ProcessFragment(fragment);
}
// Update the last received sequence.
if (packet.Header.Sequence != 0)
{
lastReceivedPacketSequence = packet.Header.Sequence;
}
}
/// <summary>
/// Handles a packet, reading the flags and processing all fragments.
/// </summary>
/// <param name="packet">ClientPacket to handle</param>
private void HandlePacket(ClientPacket packet)
{
log.DebugFormat("[{0}] Handling packet {1}", session.Account, packet.Header.Sequence);
uint issacXor = packet.Header.HasFlag(PacketHeaderFlags.EncryptedChecksum) ? ConnectionData.IssacClient.GetOffset() : 0;
if (!packet.VerifyChecksum(issacXor))
{
log.WarnFormat("[{0}] Packet {1} has invalid checksum", session.Account, packet.Header.Sequence);
}
// If we have an EchoRequest flag, we should flag to respond with an echo response on next send.
if (packet.Header.HasFlag(PacketHeaderFlags.EchoRequest))
{
FlagEcho(packet.HeaderOptional.EchoRequestClientTime);
}
// If we have an AcknowledgeSequence flag, we can clear our cached packet buffer up to that sequence.
if (packet.Header.HasFlag(PacketHeaderFlags.AckSequence))
{
AcknowledgeSequence(packet.HeaderOptional.Sequence);
}
if (packet.Header.HasFlag(PacketHeaderFlags.TimeSynch))
{
// Do something with this...
// Based on network traces these are not 1:1. Server seems to send them every 20 seconds per port.
// Client seems to send them alternatingly every 2 or 4 seconds per port.
// We will send this at a 20 second time interval. I don't know what to do with these when we receive them at this point.
}
// If the client is requesting a retransmission, pull those packets from the queue and resend them.
if (packet.Header.HasFlag(PacketHeaderFlags.RequestRetransmit))
{
foreach (uint sequence in packet.HeaderOptional.RetransmitData)
{
Retransmit(sequence);
}
}
// This should be set on the first packet to the server indicating the client is logging in.
// This is the start of a three-way handshake between the client and server (LoginRequest, ConnectRequest, ConnectResponse)
// Note this would be sent to each server a client would connect too (Login and each world).
// In our current implimenation we handle all roles in this one server.
if (packet.Header.HasFlag(PacketHeaderFlags.LoginRequest))
{
AuthenticationHandler.HandleLoginRequest(packet, session);
return;
}
// This should be set on the second packet to the server from the client.
// This comletes the three-way handshake.
if (packet.Header.HasFlag(PacketHeaderFlags.ConnectResponse))
{
sendResync = true;
AuthenticationHandler.HandleConnectResponse(packet, session);
return;
}
// Process all fragments out of the packet
foreach (ClientPacketFragment fragment in packet.Fragments)
{
ProcessFragment(fragment);
}
// Update the last received sequence.
if (packet.Header.Sequence != 0)
{
lastReceivedPacketSequence = packet.Header.Sequence;
}
}