public void UdpBroadcastMessage_Serialize()
{
// Verify that we can serialize and deserialize a message.
UdpBroadcastMessage msg;
byte[] buffer;
IPAddress address = Helper.ParseIPAddress("10.1.2.3");
msg = new UdpBroadcastMessage(UdpBroadcastMessageType.ClientRegister, address, 5, new byte[] { 0, 1, 2, 3, 4 });
msg.TimeStampUtc = new DateTime(2010, 3, 19);
Assert.AreEqual(UdpBroadcastMessageType.ClientRegister, msg.MessageType);
Assert.AreEqual(5, msg.BroadcastGroup);
CollectionAssert.AreEqual(new byte[] { 0, 1, 2, 3, 4 }, msg.Payload);
Assert.AreEqual(address, msg.SourceAddress);
buffer = msg.ToArray(sharedKey);
msg = new UdpBroadcastMessage(buffer, sharedKey);
Assert.AreEqual(UdpBroadcastMessageType.ClientRegister, msg.MessageType);
Assert.AreEqual(new DateTime(2010, 3, 19), msg.TimeStampUtc);
Assert.AreEqual(5, msg.BroadcastGroup);
CollectionAssert.AreEqual(new byte[] { 0, 1, 2, 3, 4 }, msg.Payload);
Assert.AreEqual(address, msg.SourceAddress);
// Verify that the message envelope size constant is correct.
Assert.IsTrue(UdpBroadcastMessage.EnvelopeSize >= buffer.Length - msg.Payload.Length);
}
public void UdpBroadcast_MessageNulls()
{
UdpBroadcastMessage msg;
msg = new UdpBroadcastMessage(UdpBroadcastMessageType.ServerRegister, 10);
Assert.AreEqual(10, msg.BroadcastGroup);
CollectionAssert.AreEqual(new byte[0], msg.Payload);
}
/// <summary>
/// Constructs a <see cref="UdpBroadcastMessage"/> from the parameters passed and
/// serializes it into the wire format.
/// </summary>
/// <param name="messageType">The message type.</param>
/// <param name="sourceAddress">The IP address of the message source.</param>
/// <param name="broadcastGroup">The broadcast group.</param>
/// <param name="payload">The broadcast packet payload.</param>
/// <returns>The packet bytes.</returns>
private byte[] GetMessageBytes(UdpBroadcastMessageType messageType, IPAddress sourceAddress, int broadcastGroup, byte[] payload)
{
var message = new UdpBroadcastMessage(messageType, sourceAddress, broadcastGroup, payload);
if (FixedTimestampUtc > DateTime.MinValue)
{
message.TimeStampUtc = FixedTimestampUtc;
}
return(message.ToArray(settings.SharedKey));
}
/// <summary>
/// Called when a packet is received on the socket.
/// </summary>
/// <param name="ar">The async result.</param>
private void OnReceive(IAsyncResult ar)
{
UdpBroadcastMessage message = null;
IPEndPoint recvEP = null;
int cbRecv = 0;
lock (syncLock)
{
if (socket == null)
{
return; // Client is closed
}
try
{
// Parse received packet.
cbRecv = socket.EndReceiveFrom(ar, ref rawRecvEP);
recvEP = (IPEndPoint)rawRecvEP;
if (cbRecv == 0)
{
return; // This happens when we receive an ICMP(connection-reset) from a
}
// remote host that's actively refusing an earlier packet transmission.
// We're just going to ignore this.
perf.TotalMessageRate.Increment();
perf.TotalByteRate.IncrementBy(cbRecv);
message = new UdpBroadcastMessage(Helper.Extract(recvBuf, 0, cbRecv), settings.SharedKey);
// Validate that the message timestamp is reasonable and discard
// messages with timestamps from too far in the past or too far
// in the future.
DateTime now = DateTime.UtcNow;
if (!Helper.Within(now, message.TimeStampUtc, settings.MessageTTL))
{
SysLog.LogWarning("UDP Broadcast message timestamp out of range. SystemTime={0}, Timestamp={1}, Source={2}, BroadcastGroup={3}",
now.ToString("u"), message.TimeStampUtc.ToString("u"), recvEP, message.BroadcastGroup);
return;
}
}
catch (Exception e)
{
SysLog.LogException(e);
}
finally
{
// Initiate the next receive.
try
{
rawRecvEP = new IPEndPoint(IPAddress.Any, 0);
socket.BeginReceiveFrom(recvBuf, 0, recvBuf.Length, SocketFlags.None, ref rawRecvEP, onReceive, null);
}
catch (Exception e)
{
SysLog.LogException(e);
}
}
// Process the message (if any).
if (message == null || PauseNetwork)
{
return;
}
ServerState server;
ClientState client;
switch (message.MessageType)
{
case UdpBroadcastMessageType.ServerRegister:
// Add the server to the tracking table if it's not already
// present and update its TTD.
if (!servers.TryGetValue(recvEP, out server))
{
server = new ServerState(recvEP, SysTime.Now + settings.ServerTTL);
servers.Add(recvEP, server);
}
else
{
server.TTD = SysTime.Now + settings.ServerTTL;
}
perf.AdminByteRate.IncrementBy(cbRecv);
perf.AdminMessageRate.Increment();
break;
case UdpBroadcastMessageType.ServerUnregister:
// Remove the server from the tracking table (if present).
if (servers.ContainsKey(recvEP))
{
servers.Remove(recvEP);
}
perf.AdminByteRate.IncrementBy(cbRecv);
perf.AdminMessageRate.Increment();
break;
case UdpBroadcastMessageType.ClientRegister:
// Add the client to the tracking table if it's not already
// present and update its TTD.
if (!clients.TryGetValue(recvEP, out client))
{
client = new ClientState(recvEP, message.BroadcastGroup, SysTime.Now + settings.ServerTTL);
clients.Add(recvEP, client);
}
else
{
client.TTD = SysTime.Now + settings.ServerTTL;
}
perf.AdminByteRate.IncrementBy(cbRecv);
perf.AdminMessageRate.Increment();
break;
case UdpBroadcastMessageType.ClientUnregister:
// Remove the client from the tracking table (if present).
if (clients.ContainsKey(recvEP))
{
clients.Remove(recvEP);
}
perf.AdminByteRate.IncrementBy(cbRecv);
perf.AdminMessageRate.Increment();
break;
case UdpBroadcastMessageType.Broadcast:
// Transmit the message to all clients the belong to the same broadcast group,
// if this is the master server.
if (!IsMaster)
{
return;
}
var packet = GetMessageBytes(UdpBroadcastMessageType.Broadcast, message.SourceAddress, message.BroadcastGroup, message.Payload);
int cDelivered = 0;
foreach (var c in clients.Values)
{
if (c.BroadcastGroup == message.BroadcastGroup)
{
socket.SendTo(packet, c.EndPoint);
cDelivered++;
}
}
perf.BroadcastReceiveByteRate.IncrementBy(cbRecv);
perf.BroadcastReceiveMessageRate.Increment();
perf.BroadcastSendByteRate.IncrementBy(cbRecv * packet.Length);
perf.BroadcastSendMessageRate.IncrementBy(cDelivered);
break;
}
}
}
/// <summary>
/// Called when a packet is received on the socket.
/// </summary>
/// <param name="ar">The async result.</param>
private void OnReceive(IAsyncResult ar)
{
UdpBroadcastMessage message = null;
IPEndPoint recvEP;
int cbRecv;
lock (syncLock)
{
if (socket == null)
{
return; // Client is closed
}
try
{
// Parse received packet.
cbRecv = socket.EndReceiveFrom(ar, ref rawRecvEP);
recvEP = (IPEndPoint)rawRecvEP;
if (cbRecv == 0)
{
return; // This happens when we receive an ICMP(connection-reset) from a
}
// remote host that's actively refusing an earlier packet transmission.
// We're just going to ignore this.
message = new UdpBroadcastMessage(Helper.Extract(recvBuf, 0, cbRecv), settings.SharedKey);
// Validate that the message timestamp is reasonable and discard
// messages with timestamps from too far in the past or too far
// in the future.
DateTime now = DateTime.UtcNow;
if (!Helper.Within(now, message.TimeStampUtc, settings.MessageTTL))
{
SysLog.LogWarning("UDP Broadcast message timestamp out of range. SystemTime={0}, Timestamp={1}, Source={2}, BroadcastGroup={3}",
now.ToString("u"), message.TimeStampUtc.ToString("u"), recvEP, message.BroadcastGroup);
return;
}
}
catch (Exception e)
{
SysLog.LogException(e);
}
finally
{
// Initiate the next receive.
try
{
rawRecvEP = new IPEndPoint(IPAddress.Any, 0);
socket.BeginReceiveFrom(recvBuf, 0, recvBuf.Length, SocketFlags.None, ref rawRecvEP, onReceive, null);
}
catch (Exception e)
{
SysLog.LogException(e);
}
}
}
// Process the message (if any) outside of the lock. Note that only
// broadcast messages are processed by UDP broadcast clients.
if (message == null || message.MessageType != UdpBroadcastMessageType.Broadcast || PauseNetwork)
{
return;
}
// Ignore messages that don't match the broadcast group.
if (settings.BroadcastGroup != message.BroadcastGroup)
{
return;
}
if (PacketReceived != null)
{
PacketReceived(this, new UdpBroadcastEventArgs(message.SourceAddress, message.Payload));
}
}