[VOL-1349] EPON OLT adapter (package B)

Change-Id: I634ef62c53813dcf4456f54948f13e06358e263c
diff --git a/internal/pkg/core/l2oam/msg_get_firmware_version.go b/internal/pkg/core/l2oam/msg_get_firmware_version.go
new file mode 100644
index 0000000..82995a7
--- /dev/null
+++ b/internal/pkg/core/l2oam/msg_get_firmware_version.go
@@ -0,0 +1,118 @@
+/*
+ * Copyright 2020-present Open Networking Foundation
+
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+
+ * http://www.apache.org/licenses/LICENSE-2.0
+
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package l2oam
+
+import (
+	"encoding/hex"
+	"fmt"
+
+	"github.com/google/gopacket"
+)
+
+// GenerateGetFirmwareVersion generates "Running Firmware Version" message
+func GenerateGetFirmwareVersion() gopacket.SerializableLayer {
+	tibitData := &TOAMGetRequest{
+		// IEEE 1904.2
+		Opcode: 0x03,
+		// OMI Protocol
+		Flags:      0x0050,
+		OAMPDUCode: 0xfe,
+		OUId:       []byte{0x2a, 0xea, 0x15},
+		// TiBiT OLT Management Interface
+		TOMIOpcode: 0x01,
+		// Correlation Tag
+		CTBranch:   0x0c,
+		CTType:     0x0c7a,
+		CTLength:   4,
+		CTInstance: getOltInstance(),
+		// Object Context
+		OCBranch:   0x0c,
+		OCType:     0x0dce,
+		OCLength:   4,
+		OCInstance: 0x00000000,
+		// Vd
+		VdBranch: 0xde,
+		VdLeaf:   0x001b,
+		// End
+		EndBranch: 0,
+	}
+	return tibitData
+}
+
+// GetFirmwareVersionRes is a structure for a response of "Running Firmware Version"
+type GetFirmwareVersionRes struct {
+	ComResp   TOAMGetResponse
+	AKLength  uint8
+	AKValue   []byte
+	RVLength  uint8
+	RVValue   []byte
+	BSLength  uint8
+	BSValue   []byte
+	RNLength  uint8
+	RNValue   []byte
+	BDLength  uint8
+	BDValue   []byte
+	EndBranch uint8
+}
+
+// String returns the string expression of GetFirmwareVersionRes
+func (d *GetFirmwareVersionRes) String() string {
+	message := d.ComResp.String()
+	message = fmt.Sprintf("%s, AKLength:%02x, AKValue:%s, RVLength:%02x, RVValue:%s", message, d.AKLength, hex.EncodeToString(d.AKValue), d.RVLength, hex.EncodeToString(d.RVValue))
+	message = fmt.Sprintf("%s, BSLength:%02x, BSValue:%s, RNLength:%02x, RNValue:%s", message, d.BSLength, hex.EncodeToString(d.BSValue), d.RNLength, hex.EncodeToString(d.RNValue))
+	message = fmt.Sprintf("%s, BDLength:%02x, BDValue:%s, EndBranch:%02x", message, d.BDLength, hex.EncodeToString(d.BDValue), d.EndBranch)
+	return message
+}
+
+// Len returns the length of GetFirmwareVersionRes
+func (d *GetFirmwareVersionRes) Len() int {
+	return d.ComResp.Len() + int(d.ComResp.VcLength) + 1
+}
+
+// Decode decodes byte arrays to a data structure
+func (d *GetFirmwareVersionRes) Decode(data []byte) error {
+	d.ComResp.Decode(data)
+	i := d.ComResp.Len()
+	d.AKLength = data[i]
+	i++
+	d.AKValue = data[i : i+int(d.AKLength)]
+	i += int(d.AKLength)
+	d.RVLength = data[i]
+	i++
+	d.RVValue = data[i : i+int(d.RVLength)]
+	i += int(d.RVLength)
+	d.BSLength = data[i]
+	i++
+	d.BSValue = data[i : i+int(d.BSLength)]
+	i += int(d.BSLength)
+	d.RNLength = data[i]
+	i++
+	d.RNValue = data[i : i+int(d.RNLength)]
+	i += int(d.RNLength)
+	d.BDLength = data[i]
+	i++
+	d.BDValue = data[i : i+int(d.BDLength)]
+	i += int(d.BDLength)
+	d.EndBranch = data[i]
+
+	return nil
+}
+
+// GetFirmwareVersionNumber returns a firmware version number
+func (d *GetFirmwareVersionRes) GetFirmwareVersionNumber() string {
+	return string(d.RVValue)
+}