private void Search(UdpClient client)
{
nextSearch = DateTime.Now.AddSeconds(SearchPeriod);
byte[] data = DiscoverDeviceMessage.Encode();
// UDP is unreliable, so send 3 requests at a time (per Upnp spec, sec 1.1.2)
for (int i = 0; i < 3; i++)
{
client.Send(data, data.Length, searchEndpoint);
}
}
private static void CreateSocketsAndAddGateways()
{
sockets = new List <UdpClient> ();
gatewayLists = new Dictionary <UdpClient, List <IPEndPoint> > ();
try
{
foreach (NetworkInterface n in NetworkInterface.GetAllNetworkInterfaces())
{
IPInterfaceProperties properties = n.GetIPProperties();
List <IPEndPoint> gatewayList = new List <IPEndPoint> ();
foreach (GatewayIPAddressInformation gateway in properties.GatewayAddresses)
{
if (gateway.Address.AddressFamily == AddressFamily.InterNetwork)
{
gatewayList.Add(new IPEndPoint(gateway.Address, PmpConstants.ServerPort));
}
}
if (gatewayList.Count > 0)
{
foreach (UnicastIPAddressInformation address in properties.UnicastAddresses)
{
if (address.Address.AddressFamily == AddressFamily.InterNetwork)
{
UdpClient client;
try
{
client = new UdpClient(new IPEndPoint(address.Address, 0));
}
catch (SocketException)
{
continue; // Move on to the next address.
}
gatewayLists.Add(client, gatewayList);
sockets.Add(client);
}
}
}
}
}
catch (Exception)
{
// NAT-PMP does not use multicast, so there isn't really a good fallback.
}
}
private void Search(UdpClient client)
{
// Sort out the time for the next search first. The spec says the
// timeout should double after each attempt. Once it reaches 64 seconds
// (and that attempt fails), assume no devices available
nextSearch = DateTime.Now.AddMilliseconds(timeout);
timeout *= 2;
// We've tried 9 times as per spec, try searching again in 5 minutes
if (timeout == 128 * 1000)
{
timeout = 250;
nextSearch = DateTime.Now.AddMinutes(10);
return;
}
// The nat-pmp search message. Must be sent to GatewayIP:53531
byte[] buffer = new byte[] { PmpConstants.Version, PmpConstants.OperationCode };
foreach (IPEndPoint gatewayEndpoint in gatewayLists[client])
{
client.Send(buffer, buffer.Length, gatewayEndpoint);
}
}