diff --git a/common/buf/buffer.go b/common/buf/buffer.go
index 342ba8b..10fa709 100644
--- a/common/buf/buffer.go
+++ b/common/buf/buffer.go
@@ -104,10 +104,6 @@ func With(data []byte) *Buffer {
 	}
 }
 
-func (b *Buffer) Closed() bool {
-	return b.closed
-}
-
 func (b *Buffer) Byte(index int) byte {
 	return b.data[b.start+index]
 }
diff --git a/common/bufio/buffer.go b/common/bufio/buffer.go
index ad869f3..47c35a9 100644
--- a/common/bufio/buffer.go
+++ b/common/bufio/buffer.go
@@ -2,104 +2,11 @@ package bufio
 
 import (
 	"io"
-	"os"
 	"sync"
 
-	"github.com/sagernet/sing/common"
 	"github.com/sagernet/sing/common/buf"
-	N "github.com/sagernet/sing/common/network"
 )
 
-type BufferedReader struct {
-	upstream N.ExtendedReader
-	buffer   *buf.Buffer
-}
-
-func NewBufferedReader(upstream io.Reader, buffer *buf.Buffer) *BufferedReader {
-	return &BufferedReader{
-		upstream: NewExtendedReader(upstream),
-		buffer:   buffer,
-	}
-}
-
-func (r *BufferedReader) Read(p []byte) (n int, err error) {
-	if r.buffer == nil {
-		return r.upstream.Read(p)
-	}
-	if r.buffer.Closed() {
-		return 0, os.ErrClosed
-	}
-	if r.buffer.IsEmpty() {
-		r.buffer.Reset()
-		err = r.upstream.ReadBuffer(r.buffer)
-		if err != nil {
-			r.buffer.Release()
-			return
-		}
-	}
-	return r.buffer.Read(p)
-}
-
-func (r *BufferedReader) ReadBuffer(buffer *buf.Buffer) error {
-	if r.buffer == nil {
-		return r.upstream.ReadBuffer(buffer)
-	}
-	if r.buffer.Closed() {
-		return os.ErrClosed
-	}
-	var err error
-	if r.buffer.IsEmpty() {
-		r.buffer.Reset()
-		err = r.upstream.ReadBuffer(r.buffer)
-		if err != nil {
-			r.buffer.Release()
-			return err
-		}
-	}
-	if r.buffer.Len() > buffer.FreeLen() {
-		err = common.Error(buffer.ReadFullFrom(r.buffer, buffer.FreeLen()))
-	} else {
-		err = common.Error(buffer.ReadFullFrom(r.buffer, r.buffer.Len()))
-	}
-	if err != nil {
-		r.buffer.Release()
-	}
-	return err
-}
-
-//TODO: add CopyBuffer
-/*func (r *BufferedReader) WriteTo(w io.Writer) (n int64, err error) {
-	if r.buffer == nil {
-		return Copy(w, r.upstream)
-	}
-	if r.buffer.Closed() {
-		return 0, os.ErrClosed
-	}
-	defer r.buffer.Release()
-	return CopyExtendedBuffer(NewExtendedWriter(w), NewExtendedReader(r.upstream), r.buffer)
-}*/
-
-func (r *BufferedReader) ReadCached() *buf.Buffer {
-	buffer := r.buffer
-	r.buffer = nil
-	return buffer
-}
-
-func (r *BufferedReader) Close() error {
-	r.buffer.Release()
-	r.buffer = nil
-	return nil
-}
-
-func (r *BufferedReader) Upstream() any {
-	return r.upstream
-}
-
-func (r *BufferedReader) ReaderReplaceable() bool {
-	buffer := r.buffer
-	return buffer == nil || buffer.Closed()
-}
-
 type BufferedWriter struct {
 	upstream io.Writer
 	buffer   *buf.Buffer
@@ -151,13 +58,6 @@ func (w *BufferedWriter) Fallthrough() error {
 	return nil
 }
 
-/*func (w *BufferedWriter) ReadFrom(r io.Reader) (n int64, err error) {
-	if w.buffer == nil {
-		return Copy(w.upstream, r)
-	}
-	return CopyExtendedBuffer(NewExtendedWriter(w), NewExtendedReader(r), w.buffer)
-}*/
-
 func (w *BufferedWriter) WriterReplaceable() bool {
 	return w.buffer == nil
 }
diff --git a/common/bufio/chunk.go b/common/bufio/chunk.go
index 9c60f80..56a733a 100644
--- a/common/bufio/chunk.go
+++ b/common/bufio/chunk.go
@@ -56,6 +56,14 @@ func (c *ChunkReader) Read(p []byte) (n int, err error) {
 	return c.cache.Read(p)
 }
 
+func (c *ChunkReader) ReadByte() (byte, error) {
+	buffer, err := c.ReadChunk()
+	if err != nil {
+		return 0, err
+	}
+	return buffer.ReadByte()
+}
+
 func (c *ChunkReader) ReadChunk() (*buf.Buffer, error) {
 	if c.cache == nil {
 		c.cache = buf.NewSize(c.maxChunkSize)