| /* |
| * Copyright 2015 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.protocol.ver4; |
| |
| import org.jboss.netty.buffer.ChannelBuffer; |
| import org.onosproject.bgpio.exceptions.BGPParseException; |
| import org.onosproject.bgpio.protocol.BGPKeepaliveMsg; |
| import org.onosproject.bgpio.protocol.BGPMessageReader; |
| import org.onosproject.bgpio.protocol.BGPMessageWriter; |
| import org.onosproject.bgpio.types.BGPHeader; |
| import org.onosproject.bgpio.protocol.BGPType; |
| import org.onosproject.bgpio.protocol.BGPVersion; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.google.common.base.MoreObjects; |
| |
| /** |
| * Provides BGP keep alive message. |
| */ |
| public class BGPKeepaliveMsgVer4 implements BGPKeepaliveMsg { |
| |
| /* |
| <Keepalive Message>::= <Common Header> |
| A KEEPALIVE message consists of only the message header and has a |
| length of 19 octets. |
| |
| 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 | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| |
| REFERENCE : RFC 4271 |
| */ |
| |
| protected static final Logger log = LoggerFactory |
| .getLogger(BGPKeepaliveMsgVer4.class); |
| |
| private BGPHeader bgpMsgHeader; |
| public static final byte PACKET_VERSION = 4; |
| public static final int PACKET_MINIMUM_LENGTH = 19; |
| public static final int MARKER_LENGTH = 16; |
| public static final BGPType MSG_TYPE = BGPType.KEEP_ALIVE; |
| public static byte[] marker = new byte[] {(byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, |
| (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, |
| (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff, |
| (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff}; |
| |
| public static final BGPKeepaliveMsgVer4.Reader READER = new Reader(); |
| |
| /** |
| * Reader class for reading BGP keepalive message from channel buffer. |
| */ |
| static class Reader implements BGPMessageReader<BGPKeepaliveMsg> { |
| |
| @Override |
| public BGPKeepaliveMsg readFrom(ChannelBuffer cb, BGPHeader bgpHeader) |
| throws BGPParseException { |
| |
| /* bgpHeader is not required in case of keepalive message and |
| Header is already read and no other fields except header in keepalive message.*/ |
| return new BGPKeepaliveMsgVer4(); |
| } |
| } |
| |
| /** |
| * Default constructor. |
| */ |
| public BGPKeepaliveMsgVer4() { |
| } |
| |
| /** |
| * Builder class for BGP keepalive message. |
| */ |
| static class Builder implements BGPKeepaliveMsg.Builder { |
| BGPHeader bgpMsgHeader; |
| |
| @Override |
| public Builder setHeader(BGPHeader bgpMsgHeader) { |
| this.bgpMsgHeader = bgpMsgHeader; |
| return this; |
| } |
| |
| @Override |
| public BGPKeepaliveMsg build() { |
| return new BGPKeepaliveMsgVer4(); |
| } |
| } |
| |
| @Override |
| public void writeTo(ChannelBuffer cb) { |
| WRITER.write(cb, this); |
| } |
| |
| static final Writer WRITER = new Writer(); |
| |
| /** |
| * Writer class for writing the BGP keepalive message to channel buffer. |
| */ |
| static class Writer implements BGPMessageWriter<BGPKeepaliveMsgVer4> { |
| |
| @Override |
| public void write(ChannelBuffer cb, BGPKeepaliveMsgVer4 message) { |
| |
| // write marker |
| cb.writeBytes(marker, 0, MARKER_LENGTH); |
| |
| // write length of header |
| cb.writeShort(PACKET_MINIMUM_LENGTH); |
| |
| // write the type of message |
| cb.writeByte(MSG_TYPE.getType()); |
| } |
| } |
| |
| @Override |
| public BGPVersion getVersion() { |
| return BGPVersion.BGP_4; |
| } |
| |
| @Override |
| public BGPType getType() { |
| return MSG_TYPE; |
| } |
| |
| @Override |
| public BGPHeader getHeader() { |
| return this.bgpMsgHeader; |
| } |
| |
| @Override |
| public String toString() { |
| return MoreObjects.toStringHelper(getClass()).toString(); |
| } |
| } |