Fix: multiple port string parsing overflow (#1868)

Ports in TCP and UDP should be parsed as an unsigned integer,
otherwise ports > 32767 get truncated to 32767. As this is
the case with Metadata.UDPAddr(), this fundamentally breaks
UDP connections where demand for high port numbers is high.

This commit fixes all known cases where ParseInt is used for ports,
and has been verified to fix Discord voice connections on port
50001~50004.

Fixes: d40e5e4

Co-authored-by: Hamster Tian <[email protected]>

adapter/outbound/snell.go

@@ -52,7 +52,7 @@ func streamConn(c net.Conn, option streamOption) *snell.Snell {
 // StreamConn implements C.ProxyAdapter
 func (s *Snell) StreamConn(c net.Conn, metadata *C.Metadata) (net.Conn, error) {
 	c = streamConn(c, streamOption{s.psk, s.version, s.addr, s.obfsOption})
-	port, _ := strconv.ParseInt(metadata.DstPort, 10, 16)
+	port, _ := strconv.ParseUint(metadata.DstPort, 10, 16)
 	err := snell.WriteHeader(c, metadata.String(), uint(port), s.version)
 	return c, err
 }

component/dialer/bind_others.go

@@ -58,11 +58,11 @@ func bindIfaceToDialer(ifaceName string, dialer *net.Dialer, network string, des
 		return nil
 	}
 
-	local := int64(0)
+	local := uint64(0)
 	if dialer.LocalAddr != nil {
 		_, port, err := net.SplitHostPort(dialer.LocalAddr.String())
 		if err == nil {
-			local, _ = strconv.ParseInt(port, 10, 16)
+			local, _ = strconv.ParseUint(port, 10, 16)
 		}
 	}
 
@@ -82,7 +82,7 @@ func bindIfaceToListenConfig(ifaceName string, _ *net.ListenConfig, network, add
 		port = "0"
 	}
 
-	local, _ := strconv.ParseInt(port, 10, 16)
+	local, _ := strconv.ParseUint(port, 10, 16)
 
 	addr, err := lookupLocalAddr(ifaceName, network, nil, int(local))
 	if err != nil {

constant/metadata.go

@@ -107,7 +107,7 @@ func (m *Metadata) UDPAddr() *net.UDPAddr {
 	if m.NetWork != UDP || m.DstIP == nil {
 		return nil
 	}
-	port, _ := strconv.ParseInt(m.DstPort, 10, 16)
+	port, _ := strconv.ParseUint(m.DstPort, 10, 16)
 	return &net.UDPAddr{
 		IP:   m.DstIP,
 		Port: int(port),