Allow local port control on net_socket connections

core/io/net_socket.h

@@ -67,6 +67,7 @@ class NetSocket : public Reference {
 
 	virtual bool is_open() const = 0;
 	virtual int get_available_bytes() const = 0;
+	virtual Error get_socket_address(IP_Address *r_ip, uint16_t *r_port) const = 0;
 
 	virtual Error set_broadcasting_enabled(bool p_enabled) = 0; // Returns OK if the socket option has been set successfully.
 	virtual void set_blocking_enabled(bool p_enabled) = 0;

core/io/packet_peer_udp.cpp

@@ -163,6 +163,7 @@ Error PacketPeerUDP::listen(int p_port, const IP_Address &p_bind_address, int p_
 	ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
 	ERR_FAIL_COND_V(_sock->is_open(), ERR_ALREADY_IN_USE);
 	ERR_FAIL_COND_V(!p_bind_address.is_valid() && !p_bind_address.is_wildcard(), ERR_INVALID_PARAMETER);
+	ERR_FAIL_COND_V_MSG(p_port < 0 || p_port > 65535, ERR_INVALID_PARAMETER, "The local port number must be between 0 and 65535 (inclusive).");
 
 	Error err;
 	IP::Type ip_type = IP::TYPE_ANY;
@@ -210,6 +211,7 @@ Error PacketPeerUDP::connect_to_host(const IP_Address &p_host, int p_port) {
 	ERR_FAIL_COND_V(udp_server, ERR_LOCKED);
 	ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
 	ERR_FAIL_COND_V(!p_host.is_valid(), ERR_INVALID_PARAMETER);
+	ERR_FAIL_COND_V_MSG(p_port < 1 || p_port > 65535, ERR_INVALID_PARAMETER, "The remote port number must be between 1 and 65535 (inclusive).");
 
 	Error err;
 
@@ -328,6 +330,12 @@ int PacketPeerUDP::get_packet_port() const {
 	return packet_port;
 }
 
+int PacketPeerUDP::get_local_port() const {
+	uint16_t local_port;
+	_sock->get_socket_address(nullptr, &local_port);
+	return local_port;
+}
+
 void PacketPeerUDP::set_dest_address(const IP_Address &p_address, int p_port) {
 	ERR_FAIL_COND_MSG(connected, "Destination address cannot be set for connected sockets");
 	peer_addr = p_address;
@@ -343,6 +351,7 @@ void PacketPeerUDP::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("is_connected_to_host"), &PacketPeerUDP::is_connected_to_host);
 	ClassDB::bind_method(D_METHOD("get_packet_ip"), &PacketPeerUDP::_get_packet_ip);
 	ClassDB::bind_method(D_METHOD("get_packet_port"), &PacketPeerUDP::get_packet_port);
+	ClassDB::bind_method(D_METHOD("get_local_port"), &PacketPeerUDP::get_local_port);
 	ClassDB::bind_method(D_METHOD("set_dest_address", "host", "port"), &PacketPeerUDP::_set_dest_address);
 	ClassDB::bind_method(D_METHOD("set_broadcast_enabled", "enabled"), &PacketPeerUDP::set_broadcast_enabled);
 	ClassDB::bind_method(D_METHOD("join_multicast_group", "multicast_address", "interface_name"), &PacketPeerUDP::join_multicast_group);

core/io/packet_peer_udp.h

@@ -83,6 +83,7 @@ class PacketPeerUDP : public PacketPeer {
 
 	IP_Address get_packet_address() const;
 	int get_packet_port() const;
+	int get_local_port() const;
 	void set_dest_address(const IP_Address &p_address, int p_port);
 
 	Error put_packet(const uint8_t *p_buffer, int p_buffer_size) override;

core/io/stream_peer_tcp.cpp

@@ -67,21 +67,40 @@ void StreamPeerTCP::accept_socket(Ref<NetSocket> p_sock, IP_Address p_host, uint
 	peer_port = p_port;
 }
 
-Error StreamPeerTCP::connect_to_host(const IP_Address &p_host, uint16_t p_port) {
+Error StreamPeerTCP::bind(int p_port, const IP_Address &p_host) {
 	ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
 	ERR_FAIL_COND_V(_sock->is_open(), ERR_ALREADY_IN_USE);
-	ERR_FAIL_COND_V(!p_host.is_valid(), ERR_INVALID_PARAMETER);
+	ERR_FAIL_COND_V_MSG(p_port < 0 || p_port > 65535, ERR_INVALID_PARAMETER, "The local port number must be between 0 and 65535 (inclusive).");
 
-	Error err;
 	IP::Type ip_type = p_host.is_ipv4() ? IP::TYPE_IPV4 : IP::TYPE_IPV6;
+	if (p_host.is_wildcard()) {
+		ip_type = IP::TYPE_ANY;
+	}
+	Error err = _sock->open(NetSocket::TYPE_TCP, ip_type);
+	if (err != OK) {
+		return err;
+	}
+	_sock->set_blocking_enabled(false);
+	return _sock->bind(p_host, p_port);
+}
 
-	err = _sock->open(NetSocket::TYPE_TCP, ip_type);
-	ERR_FAIL_COND_V(err != OK, FAILED);
+Error StreamPeerTCP::connect_to_host(const IP_Address &p_host, int p_port) {
+	ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
+	ERR_FAIL_COND_V(status != STATUS_NONE, ERR_ALREADY_IN_USE);
+	ERR_FAIL_COND_V(!p_host.is_valid(), ERR_INVALID_PARAMETER);
+	ERR_FAIL_COND_V_MSG(p_port < 1 || p_port > 65535, ERR_INVALID_PARAMETER, "The remote port number must be between 1 and 65535 (inclusive).");
 
-	_sock->set_blocking_enabled(false);
+	if (!_sock->is_open()) {
+		IP::Type ip_type = p_host.is_ipv4() ? IP::TYPE_IPV4 : IP::TYPE_IPV6;
+		Error err = _sock->open(NetSocket::TYPE_TCP, ip_type);
+		if (err != OK) {
+			return err;
+		}
+		_sock->set_blocking_enabled(false);
+	}
 
 	timeout = OS::get_singleton()->get_ticks_msec() + (((uint64_t)GLOBAL_GET("network/limits/tcp/connect_timeout_seconds")) * 1000);
-	err = _sock->connect_to_host(p_host, p_port);
+	Error err = _sock->connect_to_host(p_host, p_port);
 
 	if (err == OK) {
 		status = STATUS_CONNECTED;
@@ -300,10 +319,16 @@ IP_Address StreamPeerTCP::get_connected_host() const {
 	return peer_host;
 }
 
-uint16_t StreamPeerTCP::get_connected_port() const {
+int StreamPeerTCP::get_connected_port() const {
 	return peer_port;
 }
 
+int StreamPeerTCP::get_local_port() const {
+	uint16_t local_port;
+	_sock->get_socket_address(nullptr, &local_port);
+	return local_port;
+}
+
 Error StreamPeerTCP::_connect(const String &p_address, int p_port) {
 	IP_Address ip;
 	if (p_address.is_valid_ip_address()) {
@@ -319,11 +344,13 @@ Error StreamPeerTCP::_connect(const String &p_address, int p_port) {
 }
 
 void StreamPeerTCP::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("bind", "port", "host"), &StreamPeerTCP::bind, DEFVAL("*"));
 	ClassDB::bind_method(D_METHOD("connect_to_host", "host", "port"), &StreamPeerTCP::_connect);
 	ClassDB::bind_method(D_METHOD("is_connected_to_host"), &StreamPeerTCP::is_connected_to_host);
 	ClassDB::bind_method(D_METHOD("get_status"), &StreamPeerTCP::get_status);
 	ClassDB::bind_method(D_METHOD("get_connected_host"), &StreamPeerTCP::get_connected_host);
 	ClassDB::bind_method(D_METHOD("get_connected_port"), &StreamPeerTCP::get_connected_port);
+	ClassDB::bind_method(D_METHOD("get_local_port"), &StreamPeerTCP::get_local_port);
 	ClassDB::bind_method(D_METHOD("disconnect_from_host"), &StreamPeerTCP::disconnect_from_host);
 	ClassDB::bind_method(D_METHOD("set_no_delay", "enabled"), &StreamPeerTCP::set_no_delay);
 

core/io/stream_peer_tcp.h

@@ -65,10 +65,12 @@ class StreamPeerTCP : public StreamPeer {
 public:
 	void accept_socket(Ref<NetSocket> p_sock, IP_Address p_host, uint16_t p_port);
 
-	Error connect_to_host(const IP_Address &p_host, uint16_t p_port);
+	Error bind(int p_port, const IP_Address &p_host);
+	Error connect_to_host(const IP_Address &p_host, int p_port);
 	bool is_connected_to_host() const;
 	IP_Address get_connected_host() const;
-	uint16_t get_connected_port() const;
+	int get_connected_port() const;
+	int get_local_port() const;
 	void disconnect_from_host();
 
 	int get_available_bytes() const override;

core/io/tcp_server.cpp

@@ -34,6 +34,7 @@ void TCP_Server::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("listen", "port", "bind_address"), &TCP_Server::listen, DEFVAL("*"));
 	ClassDB::bind_method(D_METHOD("is_connection_available"), &TCP_Server::is_connection_available);
 	ClassDB::bind_method(D_METHOD("is_listening"), &TCP_Server::is_listening);
+	ClassDB::bind_method(D_METHOD("get_local_port"), &TCP_Server::get_local_port);
 	ClassDB::bind_method(D_METHOD("take_connection"), &TCP_Server::take_connection);
 	ClassDB::bind_method(D_METHOD("stop"), &TCP_Server::stop);
 }
@@ -42,6 +43,7 @@ Error TCP_Server::listen(uint16_t p_port, const IP_Address &p_bind_address) {
 	ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
 	ERR_FAIL_COND_V(_sock->is_open(), ERR_ALREADY_IN_USE);
 	ERR_FAIL_COND_V(!p_bind_address.is_valid() && !p_bind_address.is_wildcard(), ERR_INVALID_PARAMETER);
+	ERR_FAIL_COND_V_MSG(p_port < 0 || p_port > 65535, ERR_INVALID_PARAMETER, "The local port number must be between 0 and 65535 (inclusive).");
 
 	Error err;
 	IP::Type ip_type = IP::TYPE_ANY;
@@ -74,6 +76,12 @@ Error TCP_Server::listen(uint16_t p_port, const IP_Address &p_bind_address) {
 	return OK;
 }
 
+int TCP_Server::get_local_port() const {
+	uint16_t local_port;
+	_sock->get_socket_address(nullptr, &local_port);
+	return local_port;
+}
+
 bool TCP_Server::is_listening() const {
 	ERR_FAIL_COND_V(!_sock.is_valid(), false);
 

core/io/tcp_server.h

@@ -49,6 +49,7 @@ class TCP_Server : public Reference {
 
 public:
 	Error listen(uint16_t p_port, const IP_Address &p_bind_address = IP_Address("*"));
+	int get_local_port() const;
 	bool is_listening() const;
 	bool is_connection_available() const;
 	Ref<StreamPeerTCP> take_connection();

core/io/udp_server.cpp

@@ -34,6 +34,7 @@ void UDPServer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("listen", "port", "bind_address"), &UDPServer::listen, DEFVAL("*"));
 	ClassDB::bind_method(D_METHOD("poll"), &UDPServer::poll);
 	ClassDB::bind_method(D_METHOD("is_connection_available"), &UDPServer::is_connection_available);
+	ClassDB::bind_method(D_METHOD("get_local_port"), &UDPServer::get_local_port);
 	ClassDB::bind_method(D_METHOD("is_listening"), &UDPServer::is_listening);
 	ClassDB::bind_method(D_METHOD("take_connection"), &UDPServer::take_connection);
 	ClassDB::bind_method(D_METHOD("stop"), &UDPServer::stop);
@@ -90,6 +91,7 @@ Error UDPServer::listen(uint16_t p_port, const IP_Address &p_bind_address) {
 	ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
 	ERR_FAIL_COND_V(_sock->is_open(), ERR_ALREADY_IN_USE);
 	ERR_FAIL_COND_V(!p_bind_address.is_valid() && !p_bind_address.is_wildcard(), ERR_INVALID_PARAMETER);
+	ERR_FAIL_COND_V_MSG(p_port < 0 || p_port > 65535, ERR_INVALID_PARAMETER, "The local port number must be between 0 and 65535 (inclusive).");
 
 	Error err;
 	IP::Type ip_type = IP::TYPE_ANY;
@@ -112,11 +114,15 @@ Error UDPServer::listen(uint16_t p_port, const IP_Address &p_bind_address) {
 		stop();
 		return err;
 	}
-	bind_address = p_bind_address;
-	bind_port = p_port;
 	return OK;
 }
 
+int UDPServer::get_local_port() const {
+	uint16_t local_port;
+	_sock->get_socket_address(nullptr, &local_port);
+	return local_port;
+}
+
 bool UDPServer::is_listening() const {
 	ERR_FAIL_COND_V(!_sock.is_valid(), false);
 
@@ -176,8 +182,6 @@ void UDPServer::stop() {
 	if (_sock.is_valid()) {
 		_sock->close();
 	}
-	bind_port = 0;
-	bind_address = IP_Address();
 	List<Peer>::Element *E = peers.front();
 	while (E) {
 		E->get().peer->disconnect_shared_socket();

core/io/udp_server.h

@@ -53,21 +53,18 @@ class UDPServer : public Reference {
 	};
 	uint8_t recv_buffer[PACKET_BUFFER_SIZE];
 
-	int bind_port = 0;
-	IP_Address bind_address;
-
 	List<Peer> peers;
 	List<Peer> pending;
 	int max_pending_connections = 16;
 
 	Ref<NetSocket> _sock;
-
 	static void _bind_methods();
 
 public:
 	void remove_peer(IP_Address p_ip, int p_port);
 	Error listen(uint16_t p_port, const IP_Address &p_bind_address = IP_Address("*"));
 	Error poll();
+	int get_local_port() const;
 	bool is_listening() const;
 	bool is_connection_available() const;
 	void set_max_pending_connections(int p_max);

doc/classes/PacketPeerUDP.xml

@@ -28,6 +28,13 @@
 				[b]Note:[/b] Connecting to the remote peer does not help to protect from malicious attacks like IP spoofing, etc. Think about using an encryption technique like SSL or DTLS if you feel like your application is transferring sensitive information.
 			</description>
 		</method>
+		<method name="get_local_port" qualifiers="const">
+			<return type="int">
+			</return>
+			<description>
+				Returns the local port to which this peer is bound.
+			</description>
+		</method>
 		<method name="get_packet_ip" qualifiers="const">
 			<return type="String">
 			</return>

doc/classes/StreamPeerTCP.xml

@@ -9,6 +9,18 @@
 	<tutorials>
 	</tutorials>
 	<methods>
+		<method name="bind">
+			<return type="int" enum="Error">
+			</return>
+			<argument index="0" name="port" type="int">
+			</argument>
+			<argument index="1" name="host" type="String" default="&quot;*&quot;">
+			</argument>
+			<description>
+				Opens the TCP socket, and binds it to the specified local address.
+				This method is generally not needed, and only used to force the subsequent call to [method connect_to_host] to use the specified [code]host[/code] and [code]port[/code] as source address. This can be desired in some NAT punchthrough techniques, or when forcing the source network interface.
+			</description>
+		</method>
 		<method name="connect_to_host">
 			<return type="int" enum="Error">
 			</return>
@@ -17,7 +29,7 @@
 			<argument index="1" name="port" type="int">
 			</argument>
 			<description>
-				Connects to the specified [code]host:port[/code] pair. A hostname will be resolved if valid. Returns [constant OK] on success or [constant FAILED] on failure.
+				Connects to the specified [code]host:port[/code] pair. A hostname will be resolved if valid. Returns [constant OK] on success.
 			</description>
 		</method>
 		<method name="disconnect_from_host">
@@ -41,6 +53,13 @@
 				Returns the port of this peer.
 			</description>
 		</method>
+		<method name="get_local_port" qualifiers="const">
+			<return type="int">
+			</return>
+			<description>
+				Returns the local port to which this peer is bound.
+			</description>
+		</method>
 		<method name="get_status">
 			<return type="int" enum="StreamPeerTCP.Status">
 			</return>

doc/classes/TCP_Server.xml

@@ -9,6 +9,13 @@
 	<tutorials>
 	</tutorials>
 	<methods>
+		<method name="get_local_port" qualifiers="const">
+			<return type="int">
+			</return>
+			<description>
+				Returns the local port this server is listening to.
+			</description>
+		</method>
 		<method name="is_connection_available" qualifiers="const">
 			<return type="bool">
 			</return>

doc/classes/UDPServer.xml

@@ -123,6 +123,13 @@
 	<tutorials>
 	</tutorials>
 	<methods>
+		<method name="get_local_port" qualifiers="const">
+			<return type="int">
+			</return>
+			<description>
+				Returns the local port this server is listening to.
+			</description>
+		</method>
 		<method name="is_connection_available" qualifiers="const">
 			<return type="bool">
 			</return>