add ipv4-only support for listener

listener/rtcp/listener.go

@@ -10,6 +10,7 @@ import (
 	"github.com/go-gost/core/logger"
 	md "github.com/go-gost/core/metadata"
 	metrics "github.com/go-gost/core/metrics/wrapper"
+	xnet "github.com/go-gost/x/internal/net"
 	"github.com/go-gost/x/registry"
 )
 
@@ -20,7 +21,6 @@ func init() {
 type rtcpListener struct {
 	laddr   net.Addr
 	ln      net.Listener
-	md      metadata
 	router  *chain.Router
 	logger  logger.Logger
 	closed  chan struct{}
@@ -44,7 +44,11 @@ func (l *rtcpListener) Init(md md.Metadata) (err error) {
 		return
 	}
 
-	laddr, err := net.ResolveTCPAddr("tcp", l.options.Addr)
+	network := "tcp"
+	if xnet.IsIPv4(l.options.Addr) {
+		network = "tcp4"
+	}
+	laddr, err := net.ResolveTCPAddr(network, l.options.Addr)
 	if err != nil {
 		return
 	}