TUN-6666: Define packet package

This package defines IP and ICMP packet, decoders, encoder and flow

vendor/github.com/google/gopacket/layers/tls_cipherspec.go

@@ -0,0 +1,64 @@
+// Copyright 2018 The GoPacket Authors. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree.
+
+package layers
+
+import (
+	"errors"
+
+	"github.com/google/gopacket"
+)
+
+// TLSchangeCipherSpec defines the message value inside ChangeCipherSpec Record
+type TLSchangeCipherSpec uint8
+
+const (
+	TLSChangecipherspecMessage TLSchangeCipherSpec = 1
+	TLSChangecipherspecUnknown TLSchangeCipherSpec = 255
+)
+
+//  TLS Change Cipher Spec
+//  0  1  2  3  4  5  6  7  8
+//  +--+--+--+--+--+--+--+--+
+//  |        Message        |
+//  +--+--+--+--+--+--+--+--+
+
+// TLSChangeCipherSpecRecord defines the type of data inside ChangeCipherSpec Record
+type TLSChangeCipherSpecRecord struct {
+	TLSRecordHeader
+
+	Message TLSchangeCipherSpec
+}
+
+// DecodeFromBytes decodes the slice into the TLS struct.
+func (t *TLSChangeCipherSpecRecord) decodeFromBytes(h TLSRecordHeader, data []byte, df gopacket.DecodeFeedback) error {
+	// TLS Record Header
+	t.ContentType = h.ContentType
+	t.Version = h.Version
+	t.Length = h.Length
+
+	if len(data) != 1 {
+		df.SetTruncated()
+		return errors.New("TLS Change Cipher Spec record incorrect length")
+	}
+
+	t.Message = TLSchangeCipherSpec(data[0])
+	if t.Message != TLSChangecipherspecMessage {
+		t.Message = TLSChangecipherspecUnknown
+	}
+
+	return nil
+}
+
+// String shows the message value nicely formatted
+func (ccs TLSchangeCipherSpec) String() string {
+	switch ccs {
+	default:
+		return "Unknown"
+	case TLSChangecipherspecMessage:
+		return "Change Cipher Spec Message"
+	}
+}