3.18.4 virtual private network

core/udp.go

@@ -18,7 +18,7 @@ func UDPWrite(conn *net.UDPConn, dst net.Addr, mainType uint16, subType uint16,
 	return conn.WriteTo(msg, dst)
 }
 
-func UDPRead(conn *net.UDPConn, timeout time.Duration) (ra net.Addr, head *openP2PHeader, result []byte, len int, err error) {
+func UDPRead(conn *net.UDPConn, timeout time.Duration) (ra net.Addr, head *openP2PHeader, buff []byte, length int, err error) {
 	if timeout > 0 {
 		err = conn.SetReadDeadline(time.Now().Add(timeout))
 		if err != nil {
@@ -27,15 +27,15 @@ func UDPRead(conn *net.UDPConn, timeout time.Duration) (ra net.Addr, head *openP
 		}
 	}
 
-	result = make([]byte, 1024)
-	len, ra, err = conn.ReadFrom(result)
+	buff = make([]byte, 1024)
+	length, ra, err = conn.ReadFrom(buff)
 	if err != nil {
 		// gLog.Println(LevelDEBUG, "ReadFrom error")
 		return nil, nil, nil, 0, err
 	}
 	head = &openP2PHeader{}
-	err = binary.Read(bytes.NewReader(result[:openP2PHeaderSize]), binary.LittleEndian, head)
-	if err != nil {
+	err = binary.Read(bytes.NewReader(buff[:openP2PHeaderSize]), binary.LittleEndian, head)
+	if err != nil || head.DataLen > uint32(len(buff)-openP2PHeaderSize) {
 		gLog.Println(LvERROR, "parse p2pheader error:", err)
 		return nil, nil, nil, 0, err
 	}