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, 35 insertions, 7 deletions

diff --git a/src/network/core/address.cpp b/src/network/core/address.cpp
index 4c090c14a..9a2d3dc48 100644
--- a/src/network/core/address.cpp
+++ b/src/network/core/address.cpp
@@ -313,13 +313,12 @@ static SOCKET ListenLoopProc(addrinfo *runp)
 		Debug(net, 1, "Setting no-delay mode failed: {}", NetworkError::GetLast().AsString());
 	}
 
-	int on = 1;
-	/* The (const char*) cast is needed for windows!! */
-	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (const char*)&on, sizeof(on)) == -1) {
+	if (!SetReusePort(sock)) {
 		Debug(net, 0, "Setting reuse-address mode failed: {}", NetworkError::GetLast().AsString());
 	}
 
 #ifndef __OS2__
+	int on = 1;
 	if (runp->ai_family == AF_INET6 &&
 			setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, (const char*)&on, sizeof(on)) == -1) {
 		Debug(net, 3, "Could not disable IPv4 over IPv6: {}", NetworkError::GetLast().AsString());
@@ -401,16 +400,45 @@ void NetworkAddress::Listen(int socktype, SocketList *sockets)
 }
 
 /**
+ * Get the peer address of a socket as NetworkAddress.
+ * @param sock The socket to get the peer address of.
+ * @return The NetworkAddress of the peer address.
+ */
+/* static */ NetworkAddress NetworkAddress::GetPeerAddress(SOCKET sock)
+{
+	sockaddr_storage addr = {};
+	socklen_t addr_len = sizeof(addr);
+	if (getpeername(sock, (sockaddr *)&addr, &addr_len) != 0) {
+		Debug(net, 0, "Failed to get address of the peer: {}", NetworkError::GetLast().AsString());
+		return NetworkAddress();
+	}
+	return NetworkAddress(addr, addr_len);
+}
+
+/**
+ * Get the local address of a socket as NetworkAddress.
+ * @param sock The socket to get the local address of.
+ * @return The NetworkAddress of the local address.
+ */
+/* static */ NetworkAddress NetworkAddress::GetSockAddress(SOCKET sock)
+{
+	sockaddr_storage addr = {};
+	socklen_t addr_len = sizeof(addr);
+	if (getsockname(sock, (sockaddr *)&addr, &addr_len) != 0) {
+		Debug(net, 0, "Failed to get address of the socket: {}", NetworkError::GetLast().AsString());
+		return NetworkAddress();
+	}
+	return NetworkAddress(addr, addr_len);
+}
+
+/**
  * Get the peer name of a socket in string format.
  * @param sock The socket to get the peer name of.
  * @return The string representation of the peer name.
  */
 /* static */ const std::string NetworkAddress::GetPeerName(SOCKET sock)
 {
-	sockaddr_storage addr;
-	socklen_t addr_len = sizeof(addr);
-	getpeername(sock, (sockaddr *)&addr, &addr_len);
-	return NetworkAddress(addr, addr_len).GetAddressAsString();
+	return NetworkAddress::GetPeerAddress(sock).GetAddressAsString();
 }
 
 /**