| /* |
| * Copyright 2015-present Open Networking Laboratory |
| * |
| * 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 org.onosproject.bgpio.types; |
| |
| import org.jboss.netty.buffer.ChannelBuffer; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Provides BGP Message Header which is common for all the Messages. |
| */ |
| |
| public class BgpHeader { |
| |
| /* 0 1 2 3 |
| 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | | |
| + + |
| | | |
| + + |
| | Marker | |
| + + |
| | | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | Length | Type | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| */ |
| |
| protected static final Logger log = LoggerFactory.getLogger(BgpHeader.class); |
| |
| public static final int MARKER_LENGTH = 16; |
| public static final short DEFAULT_HEADER_LENGTH = 19; |
| |
| private byte[] marker; |
| private byte type; |
| private short length; |
| |
| /** |
| * Reset fields. |
| */ |
| public BgpHeader() { |
| this.marker = null; |
| this.length = 0; |
| this.type = 0; |
| } |
| |
| /** |
| * Constructors to initialize parameters. |
| * |
| * @param marker field in BGP header |
| * @param length message length |
| * @param type message type |
| */ |
| public BgpHeader(byte[] marker, short length, byte type) { |
| this.marker = marker; |
| this.length = length; |
| this.type = type; |
| } |
| |
| /** |
| * Sets marker field. |
| * |
| * @param value marker field |
| */ |
| public void setMarker(byte[] value) { |
| this.marker = value; |
| } |
| |
| /** |
| * Sets message type. |
| * |
| * @param value message type |
| */ |
| public void setType(byte value) { |
| this.type = value; |
| } |
| |
| /** |
| * Sets message length. |
| * |
| * @param value message length |
| */ |
| public void setLength(short value) { |
| this.length = value; |
| } |
| |
| /** |
| * Returns message length. |
| * |
| * @return message length |
| */ |
| public short getLength() { |
| return this.length; |
| } |
| |
| /** |
| * Returns message marker. |
| * |
| * @return message marker |
| */ |
| public byte[] getMarker() { |
| return this.marker; |
| } |
| |
| /** |
| * Returns message type. |
| * |
| * @return message type |
| */ |
| public byte getType() { |
| return this.type; |
| } |
| |
| /** |
| * Writes Byte stream of BGP header to channel buffer. |
| * |
| * @param cb ChannelBuffer |
| * @return length index of message header |
| */ |
| public int write(ChannelBuffer cb) { |
| |
| cb.writeBytes(getMarker(), 0, MARKER_LENGTH); |
| |
| int headerLenIndex = cb.writerIndex(); |
| cb.writeShort((short) 0); |
| cb.writeByte(type); |
| |
| return headerLenIndex; |
| } |
| |
| /** |
| * Read from channel buffer and Returns BGP header. |
| * |
| * @param cb ChannelBuffer |
| * @return object of BGPHeader |
| */ |
| public static BgpHeader read(ChannelBuffer cb) { |
| |
| byte[] marker = new byte[MARKER_LENGTH]; |
| byte type; |
| short length; |
| cb.readBytes(marker, 0, MARKER_LENGTH); |
| length = cb.readShort(); |
| type = cb.readByte(); |
| return new BgpHeader(marker, length, type); |
| } |
| } |