From 70aa04354aa1a394c1ae9425a36d7fe69b4ec43f Mon Sep 17 00:00:00 2001
From: Andy Wang <cbeuw.andy@gmail.com>
Date: Fri, 17 Apr 2020 01:03:36 +0100
Subject: [PATCH] Bounds check elimination

---
 internal/common/tls.go | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/internal/common/tls.go b/internal/common/tls.go
index 53b6b2a..7b234d9 100644
--- a/internal/common/tls.go
+++ b/internal/common/tls.go
@@ -19,11 +19,12 @@ const (
 
 func AddRecordLayer(input []byte, typ byte, ver uint16) []byte {
 	msgLen := len(input)
+	retLen := msgLen + recordLayerLength
 	var ret []byte
-	if cap(input) > msgLen+recordLayerLength {
-		ret = input[:msgLen+recordLayerLength]
+	if cap(input) >= retLen {
+		ret = input[:retLen]
 	} else {
-		ret = make([]byte, msgLen+recordLayerLength)
+		ret = make([]byte, retLen)
 	}
 	copy(ret[recordLayerLength:], input)
 	ret[0] = typ