fix: reshaping buffer maybe too long in vision

transport/vless/vision/padding.go

@@ -47,15 +47,21 @@ func ApplyPadding(buffer *buf.Buffer, command byte, userUUID *[]byte, paddingTLS
 const xrayBufSize = 8192
 
 func (vc *Conn) ReshapeBuffer(buffer *buf.Buffer) []*buf.Buffer {
-	if buffer.Len() <= xrayBufSize-PaddingHeaderLen {
+	const bufferLimit = xrayBufSize - PaddingHeaderLen
+	if buffer.Len() < bufferLimit {
 		return []*buf.Buffer{buffer}
 	}
-	cutAt := bytes.LastIndex(buffer.Bytes(), tlsApplicationDataStart)
-	if cutAt == -1 {
-		cutAt = xrayBufSize / 2
+	options := N.NewReadWaitOptions(nil, vc)
+	var buffers []*buf.Buffer
+	for buffer.Len() >= bufferLimit {
+		cutAt := bytes.LastIndex(buffer.Bytes(), tlsApplicationDataStart)
+		if cutAt < 21 || cutAt > bufferLimit {
+			cutAt = xrayBufSize / 2
+		}
+		buffer2 := options.NewBuffer() // ensure the new buffer can send used in vc.WriteBuffer
+		buf.Must(buf.Error(buffer2.ReadFullFrom(buffer, cutAt)))
+		buffers = append(buffers, buffer2)
 	}
-	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 []*buf.Buffer{buffer, buffer2}
+	buffers = append(buffers, buffer)
+	return buffers
 }

transport/vless/vision/vision.go

@@ -1,4 +1,6 @@
 // Package vision implements VLESS flow `xtls-rprx-vision` introduced by Xray-core.
+//
+// same logic as https://github.com/XTLS/Xray-core/blob/v25.9.11/proxy/proxy.go
 package vision
 
 import (
@@ -27,7 +29,7 @@ func NewConn(conn net.Conn, tlsConn net.Conn, userUUID uuid.UUID) (*Conn, error)
 		ExtendedWriter:             N.NewExtendedWriter(conn),
 		Conn:                       conn,
 		userUUID:                   userUUID,
-		packetsToFilter:            6,
+		packetsToFilter:            8,
 		readProcess:                true,
 		readFilterUUID:             true,
 		writeFilterApplicationData: true,