Fix CreatePortMapAsync await recursion issue, Add workaround for GetSpecificMappingAsync protocol problem. (lontivero#46)

* Do call the rety of CreatePortMapAsync inside CreatePortMapAsync with await.

(cherry picked from commit 7ee8dc8)

* The fritz!box 7490 has a bug where it will respond to a GetSpecificPortMappingEntry with the incorrect protocol, patch up the response with the protocol as given by the request.

(cherry picked from commit 66fa32d)

Author: bartwe

Open.Nat/Upnp/UpnpNatDevice.cs

@@ -145,6 +145,7 @@ public override async Task CreatePortMapAsync(Mapping mapping)
 			if(mapping.PrivateIP.Equals(IPAddress.None)) mapping.PrivateIP =  DeviceInfo.LocalAddress;
 
 			NatDiscoverer.TraceSource.LogInfo("CreatePortMapAsync - Creating port mapping {0}", mapping);
+			bool retry = false;
 			try
 			{
 				var message = new CreatePortMappingRequestMessage(mapping);
@@ -162,17 +163,17 @@ await _soapClient
 						mapping.Lifetime = 0;
 						// We create the mapping anyway. It must be released on shutdown.
 						mapping.LifetimeType = MappingLifetime.ForcedSession;
-						CreatePortMapAsync(mapping);
+						retry = true;
 						break;
 					case UpnpConstants.SamePortValuesRequired:
 						NatDiscoverer.TraceSource.LogWarn("Same Port Values Required - Using internal port {0}", mapping.PrivatePort);
 						mapping.PublicPort = mapping.PrivatePort;
-						CreatePortMapAsync(mapping);
+						retry = true;
 						break;
 					case UpnpConstants.RemoteHostOnlySupportsWildcard:
 						NatDiscoverer.TraceSource.LogWarn("Remote Host Only Supports Wildcard");
 						mapping.PublicIP = IPAddress.None;
-						CreatePortMapAsync(mapping);
+						retry = true;
 						break;
 					case UpnpConstants.ExternalPortOnlySupportsWildcard:
 						NatDiscoverer.TraceSource.LogWarn("External Port Only Supports Wildcard");
@@ -185,6 +186,8 @@ await _soapClient
 						throw;
 				}
 			}
+			if (retry)
+				await CreatePortMapAsync(mapping);
 		}
 #endif
 
@@ -427,7 +430,10 @@ public override async Task<Mapping> GetSpecificMappingAsync (Protocol protocol,
 
 				var messageResponse = new GetPortMappingEntryResponseMessage(responseData, DeviceInfo.ServiceType, false);
 
-				return new Mapping(messageResponse.Protocol
+				if (messageResponse.Protocol != protocol)
+					NatDiscoverer.TraceSource.LogWarn("Router responded to a protocol {0} query with a protocol {1} answer, work around applied.", protocol, messageResponse.Protocol);
+
+				return new Mapping(protocol
 					, IPAddress.Parse(messageResponse.InternalClient)
 					, messageResponse.InternalPort
 					, publicPort // messageResponse.ExternalPort is short.MaxValue