3 files changed, 11 insertions, 11 deletions
diff --git a/lib/dns/dot_client.go b/lib/dns/dot_client.go
index a3eea4af..870a1395 100644
--- a/lib/dns/dot_client.go
+++ b/lib/dns/dot_client.go
@@ -6,7 +6,6 @@ package dns
 
 import (
 	"crypto/tls"
-	"encoding/binary"
 	"errors"
 	"fmt"
 	"net"
@@ -162,12 +161,13 @@ func (cl *DoTClient) Write(msg []byte) (n int, err error) {
 	}
 
 	var (
-		lenmsg = len(msg)
-		packet = make([]byte, 0, 2+lenmsg)
+		lenmsg = uint16(len(msg))
+		packet = make([]byte, 2+lenmsg)
 	)
 
-	packet = binary.BigEndian.AppendUint16(packet, uint16(lenmsg))
-	packet = append(packet, msg...)
+	packet[0] = byte(lenmsg >> 8)
+	packet[1] = byte(lenmsg)
+	copy(packet[2:], msg)
 
 	n, err = cl.conn.Write(packet)
 	if err != nil {
diff --git a/lib/dns/server.go b/lib/dns/server.go
index 32fd8241..2090d383 100644
--- a/lib/dns/server.go
+++ b/lib/dns/server.go
@@ -476,7 +476,7 @@ func (srv *Server) handleDoHRequest(raw []byte, w http.ResponseWriter) {
 
 	req.kind = connTypeDoH
 	req.writer = cl
-	req.message.packet = append(req.message.packet[:0], raw...)
+	req.message.packet = raw
 
 	err = req.message.UnpackHeaderQuestion()
 	if err != nil {
diff --git a/lib/dns/tcp_client.go b/lib/dns/tcp_client.go
index 402540f6..da745892 100644
--- a/lib/dns/tcp_client.go
+++ b/lib/dns/tcp_client.go
@@ -5,7 +5,6 @@
 package dns
 
 import (
-	"encoding/binary"
 	"errors"
 	"fmt"
 	"io"
@@ -172,12 +171,13 @@ func (cl *TCPClient) Write(msg []byte) (n int, err error) {
 	}
 
 	var (
-		lenmsg = len(msg)
-		packet = make([]byte, 0, 2+lenmsg)
+		lenmsg = uint16(len(msg))
+		packet = make([]byte, 2+lenmsg)
 	)
 
-	packet = binary.BigEndian.AppendUint16(packet, uint16(lenmsg))
-	packet = append(packet, msg...)
+	packet[0] = byte(lenmsg >> 8)
+	packet[1] = byte(lenmsg)
+	copy(packet[2:], msg)
 
 	n, err = cl.conn.Write(packet)
 	if err != nil {