use fixed buffer size

handler/ss/udp/handler.go

@@ -7,7 +7,6 @@ import (
 	"net"
 	"time"
 
-	"github.com/go-gost/core/common/bufpool"
 	"github.com/go-gost/core/handler"
 	"github.com/go-gost/core/logger"
 	md "github.com/go-gost/core/metadata"
@@ -111,7 +110,7 @@ func (h *ssuHandler) Handle(ctx context.Context, conn net.Conn, opts ...handler.
 			pc = h.cipher.PacketConn(pc)
 		}
 		// standard UDP relay.
-		pc = ss.UDPServerConn(pc, conn.RemoteAddr(), h.md.bufferSize)
+		pc = ss.UDPServerConn(pc, conn.RemoteAddr())
 	} else {
 		if h.cipher != nil {
 			conn = ss.ShadowConn(h.cipher.StreamConn(conn), nil)
@@ -147,16 +146,13 @@ func (h *ssuHandler) Handle(ctx context.Context, conn net.Conn, opts ...handler.
 }
 
 func (h *ssuHandler) relayPacket(ctx context.Context, pc1, pc2 net.PacketConn, ro *xrecorder.HandlerRecorderObject, log logger.Logger) (err error) {
-	bufSize := h.md.bufferSize
 	errc := make(chan error, 2)
 
 	go func() {
+		var b [MaxMessageSize]byte
 		for {
 			err := func() error {
-				b := bufpool.Get(bufSize)
-				defer bufpool.Put(b)
-
-				n, addr, err := pc1.ReadFrom(b)
+				n, addr, err := pc1.ReadFrom(b[:])
 				if err != nil {
 					return err
 				}
@@ -187,12 +183,10 @@ func (h *ssuHandler) relayPacket(ctx context.Context, pc1, pc2 net.PacketConn, r
 	}()
 
 	go func() {
+		var b [MaxMessageSize]byte
 		for {
 			err := func() error {
-				b := bufpool.Get(bufSize)
-				defer bufpool.Put(b)
-
-				n, raddr, err := pc2.ReadFrom(b)
+				n, raddr, err := pc2.ReadFrom(b[:])
 				if err != nil {
 					return err
 				}

handler/ss/udp/metadata.go

@@ -8,26 +8,23 @@ import (
 	mdutil "github.com/go-gost/x/metadata/util"
 )
 
+const (
+	MaxMessageSize = math.MaxUint16
+)
+
 type metadata struct {
 	key         string
 	readTimeout time.Duration
-	bufferSize  int
 }
 
 func (h *ssuHandler) parseMetadata(md mdata.Metadata) (err error) {
 	const (
 		key         = "key"
 		readTimeout = "readTimeout"
-		bufferSize  = "bufferSize"
 	)
 
 	h.md.key = mdutil.GetString(md, key)
 	h.md.readTimeout = mdutil.GetDuration(md, readTimeout)
 
-	if bs := mdutil.GetInt(md, bufferSize); bs > 0 {
-		h.md.bufferSize = int(math.Min(math.Max(float64(bs), 512), 64*1024))
-	} else {
-		h.md.bufferSize = 4096
-	}
 	return
 }