From cdf5e0c73e36fbb01d71b08c88a6d8f4998ce228 Mon Sep 17 00:00:00 2001
From: wwqgtxx <wwqgtxx@gmail.com>
Date: Fri, 22 Aug 2025 11:27:32 +0800
Subject: [PATCH] chore: rewrite vision client write

---
 common/buf/sing.go                |  1 +
 common/net/sing.go                |  4 ++
 transport/vless/vision/conn.go    | 72 ++++++++++++-------------------
 transport/vless/vision/padding.go | 14 +++---
 4 files changed, 40 insertions(+), 51 deletions(-)

diff --git a/common/buf/sing.go b/common/buf/sing.go
index 59c650ad..73f65f15 100644
--- a/common/buf/sing.go
+++ b/common/buf/sing.go
@@ -14,6 +14,7 @@ var NewPacket = buf.NewPacket
 var NewSize = buf.NewSize
 var With = buf.With
 var As = buf.As
+var ReleaseMulti = buf.ReleaseMulti
 
 var (
 	Must  = common.Must
diff --git a/common/net/sing.go b/common/net/sing.go
index 2cd1d726..5cf97594 100644
--- a/common/net/sing.go
+++ b/common/net/sing.go
@@ -22,6 +22,10 @@ type ExtendedReader = network.ExtendedReader
 
 var WriteBuffer = bufio.WriteBuffer
 
+type ReadWaitOptions = network.ReadWaitOptions
+
+var NewReadWaitOptions = network.NewReadWaitOptions
+
 func NewDeadlineConn(conn net.Conn) ExtendedConn {
 	if deadline.IsPipe(conn) || deadline.IsPipe(network.UnwrapReader(conn)) {
 		return NewExtendedConn(conn) // pipe always have correctly deadline implement
diff --git a/transport/vless/vision/conn.go b/transport/vless/vision/conn.go
index b8367fb9..0c300e05 100644
--- a/transport/vless/vision/conn.go
+++ b/transport/vless/vision/conn.go
@@ -170,7 +170,7 @@ func (vc *Conn) WriteBuffer(buffer *buf.Buffer) (err error) {
 	if vc.needHandshake {
 		vc.needHandshake = false
 		if buffer.IsEmpty() {
-			ApplyPadding(buffer, commandPaddingContinue, vc.userUUID, false)
+			ApplyPadding(buffer, commandPaddingContinue, vc.userUUID, true) // we do a long padding to hide vless header
 		} else {
 			vc.FilterTLS(buffer.Bytes())
 			ApplyPadding(buffer, commandPaddingContinue, vc.userUUID, vc.isTLS)
@@ -190,55 +190,37 @@ func (vc *Conn) WriteBuffer(buffer *buf.Buffer) (err error) {
 	}
 
 	if vc.writeFilterApplicationData {
-		buffer2 := ReshapeBuffer(buffer)
-		defer buffer2.Release()
 		vc.FilterTLS(buffer.Bytes())
-		command := commandPaddingContinue
-		if !vc.isTLS {
-			command = commandPaddingEnd
-
-			// disable XTLS
-			//vc.readProcess = false
-			vc.writeFilterApplicationData = false
-			vc.packetsToFilter = 0
-		} else if buffer.Len() > 6 && bytes.Equal(buffer.To(3), tlsApplicationDataStart) || vc.packetsToFilter <= 0 {
-			command = commandPaddingEnd
-			if vc.enableXTLS {
-				command = commandPaddingDirect
-				vc.writeDirect = true
-			}
-			vc.writeFilterApplicationData = false
-		}
-		ApplyPadding(buffer, command, nil, vc.isTLS)
-		err = vc.ExtendedWriter.WriteBuffer(buffer)
-		if err != nil {
-			return err
-		}
-		if vc.writeDirect {
-			vc.ExtendedWriter = N.NewExtendedWriter(vc.netConn)
-			log.Debugln("XTLS Vision direct write start")
-			//time.Sleep(5 * time.Millisecond)
-		}
-		if buffer2 != nil {
-			if vc.writeDirect || !vc.isTLS {
-				return vc.ExtendedWriter.WriteBuffer(buffer2)
-			}
-			vc.FilterTLS(buffer2.Bytes())
-			command = commandPaddingContinue
-			if buffer2.Len() > 6 && bytes.Equal(buffer2.To(3), tlsApplicationDataStart) || vc.packetsToFilter <= 0 {
-				command = commandPaddingEnd
-				if vc.enableXTLS {
-					command = commandPaddingDirect
-					vc.writeDirect = true
+		buffers := vc.ReshapeBuffer(buffer)
+		applyPadding := true
+		for i, buffer := range buffers {
+			command := commandPaddingContinue
+			if applyPadding {
+				if vc.isTLS && buffer.Len() > 6 && bytes.Equal(buffer.To(3), tlsApplicationDataStart) {
+					command = commandPaddingEnd
+					if vc.enableXTLS {
+						command = commandPaddingDirect
+						vc.writeDirect = true
+					}
+					vc.writeFilterApplicationData = false
+					applyPadding = false
+				} else if !vc.isTLS12orAbove && vc.packetsToFilter <= 1 {
+					command = commandPaddingEnd
+					vc.writeFilterApplicationData = false
+					applyPadding = false
 				}
-				vc.writeFilterApplicationData = false
+				ApplyPadding(buffer, command, nil, vc.isTLS)
 			}
-			ApplyPadding(buffer2, command, nil, vc.isTLS)
-			err = vc.ExtendedWriter.WriteBuffer(buffer2)
-			if vc.writeDirect {
+
+			err = vc.ExtendedWriter.WriteBuffer(buffer)
+			if err != nil {
+				buf.ReleaseMulti(buffers[i:]) // release unwritten buffers
+				return
+			}
+			if command == commandPaddingDirect {
 				vc.ExtendedWriter = N.NewExtendedWriter(vc.netConn)
 				log.Debugln("XTLS Vision direct write start")
-				//time.Sleep(10 * time.Millisecond)
+				//time.Sleep(5 * time.Millisecond)
 			}
 		}
 		return err
diff --git a/transport/vless/vision/padding.go b/transport/vless/vision/padding.go
index 8ffb40b3..710f64c2 100644
--- a/transport/vless/vision/padding.go
+++ b/transport/vless/vision/padding.go
@@ -6,6 +6,7 @@ import (
 
 	"github.com/metacubex/mihomo/common/buf"
 	"github.com/metacubex/mihomo/log"
+	N "github.com/metacubex/sing/common/network"
 
 	"github.com/gofrs/uuid/v5"
 	"github.com/metacubex/randv2"
@@ -42,16 +43,17 @@ func ApplyPadding(buffer *buf.Buffer, command byte, userUUID *uuid.UUID, padding
 	log.Debugln("XTLS Vision write padding: command=%d, payloadLen=%d, paddingLen=%d", command, contentLen, paddingLen)
 }
 
-func ReshapeBuffer(buffer *buf.Buffer) *buf.Buffer {
-	if buffer.Len() <= buf.BufferSize-PaddingHeaderLen {
-		return nil
+func (vc *Conn) ReshapeBuffer(buffer *buf.Buffer) []*buf.Buffer {
+	const xrayBufSize = 8192
+	if buffer.Len() <= xrayBufSize-PaddingHeaderLen {
+		return []*buf.Buffer{buffer}
 	}
 	cutAt := bytes.LastIndex(buffer.Bytes(), tlsApplicationDataStart)
 	if cutAt == -1 {
-		cutAt = buf.BufferSize / 2
+		cutAt = xrayBufSize / 2
 	}
-	buffer2 := buf.New()
+	buffer2 := N.NewReadWaitOptions(nil, vc).NewBuffer() // ensure the new buffer can send used in vc.WriteBuffer
 	buffer2.Write(buffer.From(cutAt))
 	buffer.Truncate(cutAt)
-	return buffer2
+	return []*buf.Buffer{buffer, buffer2}
 }