Reject incoming YCS audio with the incorrect DG-Id.

DGIdGateway/DGIdGateway.ini

@@ -152,7 +152,7 @@ Debug=0
 # Local IMRS System Fusion Network
 Type=IMRS
 Name=South Coast
-Destination=100,44.131.4.1
+Destination=75,44.131.4.1
 Destination=75,44.131.4.2
 #RFHangTime=240
 #NetHangTime=240

DGIdGateway/YCSNetwork.cpp

@@ -18,6 +18,7 @@
 
 #include "YSFDefines.h"
 #include "YCSNetwork.h"
+#include "YSFFICH.h"
 #include "Utils.h"
 #include "Log.h"
 
@@ -223,6 +224,18 @@ void CYCSNetwork::clock(unsigned int ms)
 		m_socket.write(m_info, 80U, m_addr, m_addrLen);
 	}
 
+	if (::memcmp(buffer, "YSFD", 4U) == 0) {
+		CYSFFICH fich;
+		bool valid = fich.decode(buffer + 35U);
+		if (!valid)
+			return;
+
+		// Reject any audio which doesn't match our requested DG-Id
+		unsigned char dgId = fich.getDGId();
+		if (dgId != m_dgId)
+			return;
+	}
+
 	unsigned char len = length;
 	m_buffer.addData(&len, 1U);