Make the software safe from multiplexed TGs.

NXDNGateway/NXDNGateway.cpp

@@ -247,8 +247,16 @@ void CNXDNGateway::run()
 			// If we're linked and it's from the right place, send it on
 			if (currentId != 9999U && currentAddr.s_addr == address.s_addr && currentPort == port) {
 				// Don't pass reflector control data through to the MMDVM
-				if (::memcmp(buffer, "NXDND", 5U) == 0)
-					localNetwork.write(buffer + 10U, len - 10U, rptAddr, rptPort);
+				if (::memcmp(buffer, "NXDND", 5U) == 0) {
+					unsigned short dstId = 0U;
+					dstId |= (buffer[7U] << 8) & 0xFF00U;
+					dstId |= (buffer[8U] << 0) & 0x00FFU;
+
+					bool grp = (buffer[9U] & 0x01U) == 0x01U;
+
+					if (grp && currentId == dstId)
+						localNetwork.write(buffer + 10U, len - 10U, rptAddr, rptPort);
+				}
 
 				// Any network activity is proof that the reflector is alive
 				lostTimer.start();

NXDNReflector/Conf.cpp

@@ -37,6 +37,7 @@ enum SECTION {
 
 CConf::CConf(const std::string& file) :
 m_file(file),
+m_tg(9999U),
 m_daemon(false),
 m_lookupName(),
 m_lookupTime(0U),
@@ -98,6 +99,8 @@ bool CConf::read()
 	  if (section == SECTION_GENERAL) {
 		  if (::strcmp(key, "Daemon") == 0)
 			  m_daemon = ::atoi(value) == 1;
+		  else if (::strcmp(key, "TG") == 0)
+			  m_tg = (unsigned short)::atoi(value);
 	  } else if (section == SECTION_ID_LOOKUP) {
 		  if (::strcmp(key, "Name") == 0)
 			  m_lookupName = value;
@@ -141,6 +144,11 @@ bool CConf::getDaemon() const
 	return m_daemon;
 }
 
+unsigned short CConf::getTG() const
+{
+	return m_tg;
+}
+
 std::string CConf::getLookupName() const
 {
 	return m_lookupName;

NXDNReflector/Conf.h

@@ -31,21 +31,22 @@ public:
   bool read();
 
   // The General section
-  bool         getDaemon() const;
+  unsigned short getTG() const;
+  bool           getDaemon() const;
 
   // The Id Lookup section
-  std::string  getLookupName() const;
-  unsigned int getLookupTime() const;
+  std::string    getLookupName() const;
+  unsigned int   getLookupTime() const;
 
   // The Log section
-  unsigned int getLogDisplayLevel() const;
-  unsigned int getLogFileLevel() const;
-  std::string  getLogFilePath() const;
-  std::string  getLogFileRoot() const;
+  unsigned int   getLogDisplayLevel() const;
+  unsigned int   getLogFileLevel() const;
+  std::string    getLogFilePath() const;
+  std::string    getLogFileRoot() const;
 
   // The Network section
-  unsigned int getNetworkPort() const;
-  bool         getNetworkDebug() const;
+  unsigned int   getNetworkPort() const;
+  bool           getNetworkDebug() const;
 
   // The NXCore section
   bool           getNXCoreEnabled() const;
@@ -55,19 +56,20 @@ public:
   bool           getNXCoreDebug() const;
 
 private:
-  std::string  m_file;
-  bool         m_daemon;
+  std::string    m_file;
+  unsigned short m_tg;
+  bool           m_daemon;
 
-  std::string  m_lookupName;
-  unsigned int m_lookupTime;
+  std::string    m_lookupName;
+  unsigned int   m_lookupTime;
 
-  unsigned int m_logDisplayLevel;
-  unsigned int m_logFileLevel;
-  std::string  m_logFilePath;
-  std::string  m_logFileRoot;
+  unsigned int   m_logDisplayLevel;
+  unsigned int   m_logFileLevel;
+  std::string    m_logFilePath;
+  std::string    m_logFileRoot;
 
-  unsigned int m_networkPort;
-  bool         m_networkDebug;
+  unsigned int   m_networkPort;
+  bool           m_networkDebug;
 
   bool           m_nxCoreEnabled;
   std::string    m_nxCoreAddress;

NXDNReflector/NXDNReflector.cpp

@@ -161,6 +161,8 @@ void CNXDNReflector::run()
 	}
 #endif
 
+	unsigned short tg = m_conf.getTG();
+
 	CNXDNNetwork nxdnNetwork(m_conf.getNetworkPort(), m_conf.getNetworkDebug());
 	ret = nxdnNetwork.open();
 	if (!ret) {
@@ -262,7 +264,7 @@ void CNXDNReflector::run()
 							LogMessage("NXCore link disabled by %s at %s", callsign.c_str(), current->m_callsign.c_str());
 							closeNXCore();
 						}
-					} else {
+					} else if (grp && dstId == tg) {
 						rpt->m_timer.start();
 
 						if (current == NULL && !nxCoreActive) {
@@ -305,15 +307,21 @@ void CNXDNReflector::run()
 				if (current == NULL) {
 					if (!nxCoreActive) {
 						if ((buffer[0U] == 0x81U || buffer[0U] == 0x83U) && buffer[5U] == 0x01U) {
-							// Save the grp, src and dest for use in the NXDN Protocol messages
-							grp   = (buffer[7U] & 0x20U) == 0x20U;
-							srcId = (buffer[8U]  << 8) | buffer[9U];
-							dstId = (buffer[10U] << 8) | buffer[11U];
+							bool           tempGrp   = (buffer[7U] & 0x20U) == 0x20U;
+							unsigned short tempSrcId = (buffer[8U]  << 8) | buffer[9U];
+							unsigned short tempDstId = (buffer[10U] << 8) | buffer[11U];
 
-							std::string callsign = lookup->find(srcId);
-							LogMessage("Transmission from %s at NXCore to %s%u", callsign.c_str(), grp ? "TG " : "", dstId);
+							if (tempGrp && tempDstId == tg) {
+								// Save the grp, src and dest for use in the NXDN Protocol messages
+								grp   = tempGrp;
+								srcId = tempSrcId;
+								dstId = tempDstId;
 
-							nxCoreActive = true;
+								std::string callsign = lookup->find(srcId);
+								LogMessage("Transmission from %s at NXCore to %s%u", callsign.c_str(), grp ? "TG " : "", dstId);
+
+								nxCoreActive = true;
+							}
 						}
 					}
 

NXDNReflector/NXDNReflector.ini

@@ -1,4 +1,5 @@
 [General]
+TG=9999
 Daemon=1
 
 [Id Lookup]