Feature: allow the use of STUN to connect client and server together

This method doesn't require port-forwarding to be used, and works for
most common NAT routers in home setups. But, for sure it doesn't work
for all setups, and not everyone will be able to use this.

1 files changed, 29 insertions, 0 deletions

diff --git a/src/network/core/tcp_stun.cpp b/src/network/core/tcp_stun.cpp
new file mode 100644
index 000000000..b6aeff683
--- /dev/null
+++ b/src/network/core/tcp_stun.cpp
@@ -0,0 +1,29 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @file tcp_stun.cpp Basic functions to receive and send STUN packets.
+ */
+
+#include "../../stdafx.h"
+#include "../../debug.h"
+#include "tcp_stun.h"
+
+#include "../../safeguards.h"
+
+/**
+ * Helper for logging receiving invalid packets.
+ * @param type The received packet type.
+ * @return Always false, as it's an error.
+ */
+bool NetworkStunSocketHandler::ReceiveInvalidPacket(PacketStunType type)
+{
+	Debug(net, 0, "[tcp/stun] Received illegal packet type {}", type);
+	return false;
+}
+
+bool NetworkStunSocketHandler::Receive_SERCLI_STUN(Packet *p) { return this->ReceiveInvalidPacket(PACKET_STUN_SERCLI_STUN); }