Add change callback for 'sv_rcon_maxconnections'

If 'sv_rcon_maxconnections' is set higher than current auth socket count, reopen listen socket. If its set lower, close all sockets until auth socket count matches 'sv_rcon_maxconnections'. Sockets are getting closed in reverse order, so the netcon that connected last will be disconnected first.

r5dev/engine/server/sv_rcon.cpp

@@ -526,15 +526,23 @@ bool CRConServer::CheckForBan(CConnectedNetConsoleData* pData)
 }
 
 //-----------------------------------------------------------------------------
-// Purpose: close specific connection
+// Purpose: close connection on current index
 //-----------------------------------------------------------------------------
 void CRConServer::Disconnect(const char* szReason) // NETMGR
 {
-	CConnectedNetConsoleData* pData = m_Socket.GetAcceptedSocketData(m_nConnIndex);
+	Disconnect(m_nConnIndex, szReason);
+}
+
+//-----------------------------------------------------------------------------
+// Purpose: close specific connection by index
+//-----------------------------------------------------------------------------
+void CRConServer::Disconnect(const int nIndex, const char* szReason) // NETMGR
+{
+	CConnectedNetConsoleData* pData = m_Socket.GetAcceptedSocketData(nIndex);
 	if (pData->m_bAuthorized || sv_rcon_debug->GetBool())
 	{
 		// Inform server owner when authenticated connection has been closed.
-		netadr_t netAdr = m_Socket.GetAcceptedSocketAddress(m_nConnIndex);
+		netadr_t netAdr = m_Socket.GetAcceptedSocketAddress(nIndex);
 		if (!szReason)
 		{
 			szReason = "unknown reason";
@@ -544,7 +552,7 @@ void CRConServer::Disconnect(const char* szReason) // NETMGR
 		m_nAuthConnections--;
 	}
 
-	m_Socket.CloseAcceptedSocket(m_nConnIndex);
+	m_Socket.CloseAcceptedSocket(nIndex);
 }
 
 //-----------------------------------------------------------------------------
@@ -597,6 +605,14 @@ bool CRConServer::IsInitialized(void) const
 	return m_bInitialized;
 }
 
+//-----------------------------------------------------------------------------
+// Purpose: returns the number of authenticated connections
+//-----------------------------------------------------------------------------
+int CRConServer::GetAuthenticatedCount(void) const
+{
+	return m_nAuthConnections;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 CRConServer g_RCONServer;
 CRConServer* RCONServer() // Singleton RCON Server.

r5dev/engine/server/sv_rcon.h

@@ -34,7 +34,6 @@ public:
 		const int nMessageType = static_cast<int>(LogType_t::LOG_NET)) const;
 
 	bool SendToAll(const char* pMsgBuf, const int nMsgLen) const;
-
 	bool Serialize(vector<char>& vecBuf, const char* pResponseMsg, const char* pResponseVal, const sv_rcon::response_t responseType,
 		const int nMessageId = static_cast<int>(eDLL_T::NETCON), const int nMessageType = static_cast<int>(LogType_t::LOG_NET)) const;
 
@@ -47,11 +46,14 @@ public:
 	bool CheckForBan(CConnectedNetConsoleData* pData);
 
 	virtual void Disconnect(const char* szReason = nullptr) override;
+	void Disconnect(const int nIndex, const char* szReason = nullptr);
 	void CloseNonAuthConnection(void);
 
 	bool ShouldSend(const sv_rcon::response_t responseType) const;
 	bool IsInitialized(void) const;
 
+	int GetAuthenticatedCount(void) const;
+
 private:
 	int                      m_nConnIndex;
 	int                      m_nAuthConnections;

r5dev/tier1/cvar.cpp

@@ -350,7 +350,7 @@ void ConVar::StaticInit(void)
 	sv_rcon_maxfailures = ConVar::StaticCreate("sv_rcon_maxfailures", "10", FCVAR_RELEASE, "Max number of times a user can fail rcon authentication before being banned.", true, 1.f, false, 0.f, nullptr, nullptr);
 	sv_rcon_maxignores  = ConVar::StaticCreate("sv_rcon_maxignores" , "15", FCVAR_RELEASE, "Max number of times a user can ignore the instruction message before being banned.", true, 1.f, false, 0.f, nullptr, nullptr);
 	sv_rcon_maxsockets  = ConVar::StaticCreate("sv_rcon_maxsockets" , "32", FCVAR_RELEASE, "Max number of accepted sockets before the server starts closing redundant sockets.", true, 1.f, false, 0.f, nullptr, nullptr);
-	sv_rcon_maxconnections    = ConVar::StaticCreate("sv_rcon_maxconnections"   , "1"   , FCVAR_RELEASE, "Max number of authenticated connections before the server closes the listen socket.", true, 1.f, false, 0.f, nullptr, nullptr);
+	sv_rcon_maxconnections    = ConVar::StaticCreate("sv_rcon_maxconnections"   , "1"   , FCVAR_RELEASE, "Max number of authenticated connections before the server closes the listen socket.", true, 1.f, false, 0.f, &RCON_ConnectionCountChanged_f, nullptr);
 	sv_rcon_maxpacketsize     = ConVar::StaticCreate("sv_rcon_maxpacketsize"    , "1024", FCVAR_RELEASE, "Max number of bytes allowed in a command packet from a non-authenticated net console.", true, 0.f, false, 0.f, nullptr, nullptr);
 	sv_rcon_whitelist_address = ConVar::StaticCreate("sv_rcon_whitelist_address", ""    , FCVAR_RELEASE, "This address is not considered a 'redundant' socket and will never be banned for failed authentication attempts.", false, 0.f, false, 0.f, &RCON_WhiteListAddresChanged_f, "Format: '::ffff:127.0.0.1'");
 

r5dev/vstdlib/callback.cpp

@@ -979,7 +979,51 @@ void RCON_WhiteListAddresChanged_f(IConVar* pConVar, const char* pOldString, flo
 
 		if (!RCONServer()->SetWhiteListAddress(pConVarRef->GetString()))
 		{
-			Warning(eDLL_T::COMMON, "Failed to set RCON whitelist address: %s\n", pConVarRef->GetString());
+			Warning(eDLL_T::SERVER, "Failed to set RCON whitelist address: %s\n", pConVarRef->GetString());
+		}
+	}
+}
+
+/*
+=====================
+RCON_ConnectionCountChanged_f
+
+  Change max connection
+  count on RCON server
+=====================
+*/
+void RCON_ConnectionCountChanged_f(IConVar* pConVar, const char* pOldString, float flOldValue)
+{
+	if (!RCONServer()->IsInitialized())
+		return; // Not initialized; no sockets at this point.
+
+	if (ConVar* pConVarRef = g_pCVar->FindVar(pConVar->GetCommandName()))
+	{
+		if (strcmp(pOldString, pConVarRef->GetString()) == NULL)
+			return; // Same count.
+
+		const int maxCount = pConVarRef->GetInt();
+
+		int count = RCONServer()->GetAuthenticatedCount();
+		CSocketCreator* pCreator = RCONServer()->GetSocketCreator();
+
+		if (count < maxCount)
+		{
+			if (!pCreator->IsListening())
+			{
+				pCreator->CreateListenSocket(*RCONServer()->GetNetAddress());
+			}
+		}
+		else
+		{
+			while (count > maxCount)
+			{
+				RCONServer()->Disconnect(count-1, "too many authenticated sockets");
+				count = RCONServer()->GetAuthenticatedCount();
+			}
+
+			pCreator->CloseListenSocket();
+			RCONServer()->CloseNonAuthConnection();
 		}
 	}
 }

r5dev/vstdlib/callback.h

@@ -53,6 +53,7 @@ void RCON_Disconnect_f(const CCommand& args);
 void RCON_PasswordChanged_f(IConVar* pConVar, const char* pOldString, float flOldValue);
 #ifndef CLIENT_DLL
 void RCON_WhiteListAddresChanged_f(IConVar* pConVar, const char* pOldString, float flOldValue);
+void RCON_ConnectionCountChanged_f(IConVar* pConVar, const char* pOldString, float flOldValue);
 void SQVM_ServerScript_f(const CCommand& args);
 #endif // !CLIENT_DLL
 #ifndef DEDICATED