From 40ae019e1dcad6bd46177be49f39c1e0c5074f3c Mon Sep 17 00:00:00 2001
From: Hellojack <106379370+H1JK@users.noreply.github.com>
Date: Sun, 26 Feb 2023 11:11:55 +0800
Subject: [PATCH] fix: Vision filter TLS 1.2

---
 transport/vless/conn.go   | 15 ++++++++++-----
 transport/vless/filter.go | 13 ++++++++-----
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/transport/vless/conn.go b/transport/vless/conn.go
index 4750276e3..5817083d5 100644
--- a/transport/vless/conn.go
+++ b/transport/vless/conn.go
@@ -133,15 +133,16 @@ func (vc *Conn) ReadBuffer(buffer *buf.Buffer) error {
 				vc.readProcess = false
 				return vc.ReadBuffer(buffer)
 			case commandPaddingDirect:
+				needReturn := false
 				if vc.input != nil {
 					_, err := buffer.ReadFrom(vc.input)
 					if err != nil {
 						return err
 					}
 					if vc.input.Len() == 0 {
+						needReturn = true
 						vc.input = nil
-					}
-					if buffer.IsFull() {
+					} else { // buffer is full
 						return nil
 					}
 				}
@@ -150,6 +151,7 @@ func (vc *Conn) ReadBuffer(buffer *buf.Buffer) error {
 					if err != nil {
 						return err
 					}
+					needReturn = true
 					if vc.rawInput.Len() == 0 {
 						vc.rawInput = nil
 					}
@@ -159,6 +161,9 @@ func (vc *Conn) ReadBuffer(buffer *buf.Buffer) error {
 					vc.ExtendedReader = N.NewExtendedReader(vc.Conn)
 					log.Debugln("XTLS Vision direct read start")
 				}
+				if needReturn {
+					return nil
+				}
 			default:
 				err := fmt.Errorf("XTLS Vision read unknown command: %d", vc.readLastCommand)
 				log.Debugln(err.Error())
@@ -489,9 +494,9 @@ func newConn(conn net.Conn, client *Client, dst *DstAddr) (*Conn, error) {
 			r, _ := t.FieldByName("rawInput")
 			c.input = (*bytes.Reader)(unsafe.Pointer(p + i.Offset))
 			c.rawInput = (*bytes.Buffer)(unsafe.Pointer(p + r.Offset))
-			if _, ok := c.Conn.(*net.TCPConn); !ok {
-				log.Debugln("XTLS underlying conn is not *net.TCPConn, got %s", reflect.TypeOf(conn).Name())
-			}
+			// if _, ok := c.Conn.(*net.TCPConn); !ok {
+			// 	log.Debugln("XTLS underlying conn is not *net.TCPConn, got %T", c.Conn)
+			// }
 		}
 	}
 
diff --git a/transport/vless/filter.go b/transport/vless/filter.go
index 15d595bc3..5e00b5c36 100644
--- a/transport/vless/filter.go
+++ b/transport/vless/filter.go
@@ -50,10 +50,13 @@ func (vc *Conn) FilterTLS(p []byte) (index int) {
 	}
 
 	if vc.remainingServerHello > 0 {
-		end := vc.remainingServerHello
-		vc.remainingServerHello -= end
-		if end > uint16(lenP) {
-			end = uint16(lenP)
+		end := int(vc.remainingServerHello)
+		if index+end > lenP {
+			end = lenP
+			vc.remainingServerHello -= uint16(end - index)
+		} else {
+			vc.remainingServerHello -= uint16(end)
+			end += index
 		}
 		if bytes.Contains(p[index:end], tls13SupportedVersions) {
 			// TLS 1.3 Client Hello
@@ -64,7 +67,7 @@ func (vc *Conn) FilterTLS(p []byte) (index int) {
 			log.Debugln("XTLS Vision found TLS 1.3, packetLength=", lenP, ", CipherSuite=", cs)
 			vc.packetsToFilter = 0
 			return
-		} else if vc.remainingServerHello < 0 {
+		} else if vc.remainingServerHello <= 0 {
 			log.Debugln("XTLS Vision found TLS 1.2, packetLength=", lenP)
 			vc.packetsToFilter = 0
 			return