/// <summary>
/// Handles a received netgram
/// </summary>
/// <param name="message">The netgram received message</param>
private void _handleReceivedNetgram(NetgramReceivedMessage message)
{
var buffer = message.Segment.Buffer;
var offset = message.Segment.Offset;
var end = message.Segment.End;
NetgramHeader header = new NetgramHeader();
offset = header.Deserialize(buffer, offset, end);
InboundAppgram appgram = null;
lock (_lock)
{
if (header.IsNetworkMessage)
{
_processNetworkMessage(message, header, buffer, offset, end);
}
else
{
appgram = _createInboundAppgram(message, header, buffer, offset, end);
}
}
if (appgram != null)
{
_appgramObservers.Next(appgram);
}
}
/// <summary>
/// Creates an inbound appgram
/// </summary>
/// <param name="netgram">The received netgram</param>
/// <param name="header">The header of the netgram</param>
/// <param name="buffer">The buffer containing the appgram</param>
/// <param name="offset">The offset of the appgram within the buffer</param>
/// <param name="end">The end of the content in the buffer</param>
private InboundAppgram _createInboundAppgram(NetgramReceivedMessage netgram, NetgramHeader header, byte[] buffer, int offset, int end)
{
InboundAppgram appgram = new InboundAppgram();
appgram.Source = _getSource(netgram, header);
appgram.ExpectingReply = header.ExpectingReply;
appgram.Priority = header.Priority;
appgram.Segment = new BufferSegment(buffer, offset, end);
return(appgram);
}
/// <summary>
/// Retrieves the qualified source address of a netgram
/// </summary>
/// <param name="netgram">The received netgram</param>
/// <param name="header">The netgram header</param>
/// <returns>The qualified source address</returns>
private Address _getSource(NetgramReceivedMessage netgram, NetgramHeader header)
{
if (header.Source != null)
{
return(header.Source);
}
else
{
Route route = _table.GetRouteByPortId(netgram.PortId);
return(new Address(route.Network, netgram.Source));
}
}
/// <summary>
/// Called whenever a packet is captured on the capture device
/// </summary>
/// <param name="sender">The sender of the event</param>
/// <param name="e">The event args</param>
private void _onPacketArrival(object sender, CaptureEventArgs e)
{
// don't process any packet too short to not be valid
if (e.Packet.Data.Length < _minimumPacketLength)
{
return;
}
// don't process any packets sent by the local device
if (_isOutboundPacket(e.Packet.Data))
{
return;
}
byte[] buffer = e.Packet.Data;
int offset = 0;
Mac destination, source;
int length;
byte dsap, ssap, control;
destination = new Mac(buffer, offset, 6);
offset += 6;
source = new Mac(buffer, offset, 6);
offset += 6;
length = buffer.ReadUInt16(offset);
offset += 2;
dsap = buffer[offset++];
ssap = buffer[offset++];
control = buffer[offset++];
// don't process non-BACnet packets
if (dsap != 0x82 || ssap != 0x82 || control != 0x03)
{
return;
}
NetgramReceivedMessage message = new NetgramReceivedMessage(
this.PortId,
source,
new BufferSegment(buffer, offset, buffer.Length));
if (Session != null)
{
Session.QueueMessage(message);
}
}
/// <summary>
/// Processes a received i am router to network message
/// </summary>
/// <param name="netgram">The received netgram</param>
/// <param name="header">The netgram header</param>
/// <param name="message">The i am router to network message</param>
private void _processIAmRouterToNetworkMessage(NetgramReceivedMessage netgram, NetgramHeader header, IAmRouterToNetworkMessage message)
{
// we only use routes from directly connected devices
if (header.Destination == null && message.Networks != null)
{
foreach (var network in message.Networks)
{
var route = _table.AddRemoteRoute(network, netgram.PortId, netgram.Source);
for (var node = _netgramQueue.First; node != null;)
{
if (node.Value.Destination.Network == network)
{
var temp = node.Next;
_sendWithRoute(route, node.Value);
_netgramQueue.Remove(node);
node = temp;
}
else
{
node = node.Next;
}
}
for (var node = _networkSearchTimers.First; node != null;)
{
if (node.Value.Network == network)
{
var temp = node.Next;
node.Value.Dispose();
_networkSearchTimers.Remove(node);
node = temp;
}
else
{
node = node.Next;
}
}
}
}
}
/// <summary>
/// Called whenever a datagram is received
/// </summary>
/// <param name="ep">The IPEndPoint of the sending device</param>
/// <param name="buffer">The buffer containing the datagram</param>
/// <param name="length">The length of the received datagram</param>
/// <returns>The inbound netgram to propagate, if any</returns>
private void _onDatagramReceived(IPEndPoint ep, byte[] buffer, int length)
{
int offset = 0;
BvlcHeader header = null;
IBvlcMessage message = null;
NetgramReceivedMessage netgram = null;
Mac mac = IPUtils.IPEndPointToMac(ep);
try
{
if (length < 4)
{
throw new Exception("Received datagram under 4 bytes long");
}
header = new BvlcHeader();
offset = header.Deserialize(buffer, offset);
if (header.Length != length)
{
throw new Exception("Received bvlc datagram with non-matching lengths");
}
message = _createMessage(header.Function);
offset = message.Deserialize(buffer, offset);
lock (_lock)
{
netgram = _processMessage(mac, message, buffer, offset, length);
}
if (netgram != null && Session != null)
{
Session.QueueMessage(netgram);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.ToString());
}
}
/// <summary>
/// Processes a received network message
/// </summary>
/// <param name="netgram">The netgram received message</param>
/// <param name="header">The header of the netgram</param>
/// <param name="buffer">The buffer containing the appgram</param>
/// <param name="offset">The offset of the appgram within the buffer</param>
/// <param name="end">The end of the content in the buffer</param>
private void _processNetworkMessage(NetgramReceivedMessage netgram, NetgramHeader header, byte[] buffer, int offset, int end)
{
try
{
INetworkMessage message = _createNetworkMessage(header.VendorId, header.MessageType);
offset = message.Deserialize(buffer, offset, end);
switch (message.Type)
{
case MessageType.WhoIsRouterToNetwork:
_processWhoIsRouterToNetworkMessage(netgram, header, (WhoIsRouterToNetworkMessage)message);
break;
case MessageType.IAmRouterToNetwork:
_processIAmRouterToNetworkMessage(netgram, header, (IAmRouterToNetworkMessage)message);
break;
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
/// <summary>
/// Processes a received who is router to network message
/// </summary>
/// <param name="netgram">The netgram received message</param>
/// <param name="header">The netgram header</param>
/// <param name="message">The who is router to network message</param>
private void _processWhoIsRouterToNetworkMessage(NetgramReceivedMessage netgram, NetgramHeader header, WhoIsRouterToNetworkMessage message)
{
}