| /* |
| * 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 java.util.LinkedList; |
| import java.util.ListIterator; |
| |
| import org.jboss.netty.buffer.ChannelBuffer; |
| import org.onosproject.bgpio.exceptions.BGPParseException; |
| import org.onosproject.bgpio.protocol.BGPMessageReader; |
| import org.onosproject.bgpio.protocol.BGPMessageWriter; |
| import org.onosproject.bgpio.protocol.BGPOpenMsg; |
| import org.onosproject.bgpio.protocol.BGPType; |
| import org.onosproject.bgpio.protocol.BGPVersion; |
| import org.onosproject.bgpio.types.BGPErrorType; |
| import org.onosproject.bgpio.types.BGPHeader; |
| import org.onosproject.bgpio.types.BGPValueType; |
| import org.onosproject.bgpio.util.Validation; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import com.google.common.base.MoreObjects; |
| |
| /** |
| * Provides BGP open message. |
| */ |
| public class BGPOpenMsgVer4 implements BGPOpenMsg { |
| |
| /* |
| 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 |
| +-+-+-+-+-+-+-+-+ |
| | Version | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | My Autonomous System | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | Hold Time | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | BGP Identifier | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | Opt Parm Len | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| | Optional Parameters (variable) | |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| OPEN Message Format |
| REFERENCE : RFC 4271 |
| */ |
| |
| protected static final Logger log = LoggerFactory.getLogger(BGPOpenMsgVer4.class); |
| |
| public static final byte PACKET_VERSION = 4; |
| public static final int OPEN_MSG_MINIMUM_LENGTH = 10; |
| public static final int MSG_HEADER_LENGTH = 19; |
| public static final int MARKER_LENGTH = 16; |
| public static final int DEFAULT_HOLD_TIME = 120; |
| public static final int OPT_PARA_TYPE_CAPABILITY = 2; |
| public static final BGPType MSG_TYPE = BGPType.OPEN; |
| public static final 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 BGPHeader DEFAULT_OPEN_HEADER = new BGPHeader(MARKER, |
| (short) OPEN_MSG_MINIMUM_LENGTH, (byte) 0X01); |
| private BGPHeader bgpMsgHeader; |
| private byte version; |
| private short asNumber; |
| private short holdTime; |
| private int bgpId; |
| private LinkedList<BGPValueType> capabilityTlv; |
| |
| public static final BGPOpenMsgVer4.Reader READER = new Reader(); |
| |
| /** |
| * reset variables. |
| */ |
| public BGPOpenMsgVer4() { |
| this.bgpMsgHeader = null; |
| this.version = 0; |
| this.holdTime = 0; |
| this.asNumber = 0; |
| this.bgpId = 0; |
| this.capabilityTlv = null; |
| } |
| |
| /** |
| * Constructor to initialize all variables of BGP Open message. |
| * |
| * @param bgpMsgHeader |
| * BGP Header in open message |
| * @param version |
| * BGP version in open message |
| * @param holdTime |
| * hold time in open message |
| * @param asNumber |
| * AS number in open message |
| * @param bgpId |
| * BGP identifier in open message |
| * @param capabilityTlv |
| * capabilities in open message |
| */ |
| public BGPOpenMsgVer4(BGPHeader bgpMsgHeader, byte version, short asNumber, short holdTime, |
| int bgpId, LinkedList<BGPValueType> capabilityTlv) { |
| this.bgpMsgHeader = bgpMsgHeader; |
| this.version = version; |
| this.asNumber = asNumber; |
| this.holdTime = holdTime; |
| this.bgpId = bgpId; |
| this.capabilityTlv = capabilityTlv; |
| } |
| |
| @Override |
| public BGPHeader getHeader() { |
| return this.bgpMsgHeader; |
| } |
| |
| @Override |
| public BGPVersion getVersion() { |
| return BGPVersion.BGP_4; |
| } |
| |
| @Override |
| public BGPType getType() { |
| return MSG_TYPE; |
| } |
| |
| @Override |
| public short getHoldTime() { |
| return this.holdTime; |
| } |
| |
| @Override |
| public short getAsNumber() { |
| return this.asNumber; |
| } |
| |
| @Override |
| public int getBgpId() { |
| return this.bgpId; |
| } |
| |
| @Override |
| public LinkedList<BGPValueType> getCapabilityTlv() { |
| return this.capabilityTlv; |
| } |
| |
| /** |
| * Reader class for reading BGP open message from channel buffer. |
| */ |
| public static class Reader implements BGPMessageReader<BGPOpenMsg> { |
| |
| @Override |
| public BGPOpenMsg readFrom(ChannelBuffer cb, BGPHeader bgpHeader) throws BGPParseException { |
| |
| byte version; |
| short holdTime; |
| short asNumber; |
| int bgpId; |
| byte optParaLen = 0; |
| byte optParaType; |
| byte capParaLen = 0; |
| LinkedList<BGPValueType> capabilityTlv = new LinkedList<>(); |
| |
| if (cb.readableBytes() < OPEN_MSG_MINIMUM_LENGTH) { |
| log.error("[readFrom] Invalid length: Packet size is less than the minimum length "); |
| Validation.validateLen(BGPErrorType.OPEN_MESSAGE_ERROR, BGPErrorType.BAD_MESSAGE_LENGTH, |
| cb.readableBytes()); |
| } |
| |
| // Read version |
| version = cb.readByte(); |
| if (version != PACKET_VERSION) { |
| log.error("[readFrom] Invalid version: " + version); |
| throw new BGPParseException(BGPErrorType.OPEN_MESSAGE_ERROR, |
| BGPErrorType.UNSUPPORTED_VERSION_NUMBER, null); |
| } |
| |
| // Read AS number |
| asNumber = cb.readShort(); |
| |
| // Read Hold timer |
| holdTime = cb.readShort(); |
| |
| // Read BGP Identifier |
| bgpId = cb.readInt(); |
| |
| // Read optional parameter length |
| optParaLen = cb.readByte(); |
| |
| // Read Capabilities if optional parameter length is greater than 0 |
| if (optParaLen != 0) { |
| // Read optional parameter type |
| optParaType = cb.readByte(); |
| |
| // Read optional parameter length |
| capParaLen = cb.readByte(); |
| |
| if (cb.readableBytes() < capParaLen) { |
| throw new BGPParseException(BGPErrorType.OPEN_MESSAGE_ERROR, (byte) 0, null); |
| } |
| |
| ChannelBuffer capaCb = cb.readBytes(capParaLen); |
| |
| // Parse capabilities only if optional parameter type is 2 |
| if ((optParaType == OPT_PARA_TYPE_CAPABILITY) && (capParaLen != 0)) { |
| capabilityTlv = parseCapabilityTlv(capaCb); |
| } else { |
| throw new BGPParseException(BGPErrorType.OPEN_MESSAGE_ERROR, |
| BGPErrorType.UNSUPPORTED_OPTIONAL_PARAMETER, null); |
| } |
| } |
| return new BGPOpenMsgVer4(bgpHeader, version, asNumber, holdTime, bgpId, capabilityTlv); |
| } |
| } |
| |
| /** |
| * Parsing capabilities. |
| * |
| * @param cb of type channel buffer |
| * @return capabilityTlv of open message |
| * @throws BGPParseException while parsing capabilities |
| */ |
| protected static LinkedList<BGPValueType> parseCapabilityTlv(ChannelBuffer cb) throws BGPParseException { |
| |
| LinkedList<BGPValueType> capabilityTlv = new LinkedList<>(); |
| |
| // TODO: Capability parsing |
| return capabilityTlv; |
| } |
| |
| /** |
| * Builder class for BGP open message. |
| */ |
| static class Builder implements BGPOpenMsg.Builder { |
| |
| private boolean isHeaderSet = false; |
| private BGPHeader bgpMsgHeader; |
| private boolean isHoldTimeSet = false; |
| private short holdTime; |
| private boolean isAsNumSet = false; |
| private short asNumber; |
| private boolean isBgpIdSet = false; |
| private int bgpId; |
| |
| LinkedList<BGPValueType> capabilityTlv = new LinkedList<>(); |
| |
| @Override |
| public BGPOpenMsg build() throws BGPParseException { |
| BGPHeader bgpMsgHeader = this.isHeaderSet ? this.bgpMsgHeader : DEFAULT_OPEN_HEADER; |
| short holdTime = this.isHoldTimeSet ? this.holdTime : DEFAULT_HOLD_TIME; |
| |
| if (!this.isAsNumSet) { |
| throw new BGPParseException("BGP AS number is not set (mandatory)"); |
| } |
| |
| if (!this.isBgpIdSet) { |
| throw new BGPParseException("BGPID is not set (mandatory)"); |
| } |
| |
| // TODO: capabilities build |
| |
| return new BGPOpenMsgVer4(bgpMsgHeader, PACKET_VERSION, this.asNumber, holdTime, this.bgpId, |
| this.capabilityTlv); |
| } |
| |
| @Override |
| public BGPHeader getHeader() { |
| return this.bgpMsgHeader; |
| } |
| |
| @Override |
| public Builder setHeader(BGPHeader bgpMsgHeader) { |
| this.bgpMsgHeader = bgpMsgHeader; |
| return this; |
| } |
| |
| @Override |
| public BGPVersion getVersion() { |
| return BGPVersion.BGP_4; |
| } |
| |
| @Override |
| public BGPType getType() { |
| return MSG_TYPE; |
| } |
| |
| @Override |
| public short getHoldTime() { |
| return this.holdTime; |
| } |
| |
| @Override |
| public short getAsNumber() { |
| return this.asNumber; |
| } |
| |
| @Override |
| public int getBgpId() { |
| return this.bgpId; |
| } |
| |
| @Override |
| public LinkedList<BGPValueType> getCapabilityTlv() { |
| return this.capabilityTlv; |
| } |
| |
| @Override |
| public Builder setHoldTime(short holdTime) { |
| this.holdTime = holdTime; |
| this.isHoldTimeSet = true; |
| return this; |
| } |
| |
| @Override |
| public Builder setAsNumber(short asNumber) { |
| this.asNumber = asNumber; |
| this.isAsNumSet = true; |
| return this; |
| } |
| |
| @Override |
| public Builder setBgpId(int bgpId) { |
| this.bgpId = bgpId; |
| this.isBgpIdSet = true; |
| return this; |
| } |
| |
| @Override |
| public Builder setCapabilityTlv(LinkedList<BGPValueType> capabilityTlv) { |
| this.capabilityTlv = capabilityTlv; |
| return this; |
| } |
| } |
| |
| @Override |
| public void writeTo(ChannelBuffer cb) { |
| try { |
| WRITER.write(cb, this); |
| } catch (BGPParseException e) { |
| log.debug("[writeTo] Error: " + e.toString()); |
| } |
| } |
| |
| public static final Writer WRITER = new Writer(); |
| |
| /** |
| * Writer class for writing BGP open message to channel buffer. |
| */ |
| public static class Writer implements BGPMessageWriter<BGPOpenMsgVer4> { |
| |
| @Override |
| public void write(ChannelBuffer cb, BGPOpenMsgVer4 message) throws BGPParseException { |
| |
| int optParaLen = 0; |
| |
| int startIndex = cb.writerIndex(); |
| |
| // write common header and get msg length index |
| int msgLenIndex = message.bgpMsgHeader.write(cb); |
| |
| if (msgLenIndex <= 0) { |
| throw new BGPParseException("Unable to write message header."); |
| } |
| |
| // write version in 1-octet |
| cb.writeByte(message.version); |
| |
| // TODO : Write AS number based on capabilities |
| cb.writeShort(message.asNumber); |
| |
| // write HoldTime in next 2-octet |
| cb.writeShort(message.holdTime); |
| |
| // write BGP Identifier in next 4-octet |
| cb.writeInt(message.bgpId); |
| |
| // store the index of Optional parameter length |
| int optParaLenIndex = cb.writerIndex(); |
| |
| // set optional parameter length as 0 |
| cb.writeByte(0); |
| |
| // Pack capability TLV |
| optParaLen = message.packCapabilityTlv(cb, message); |
| |
| if (optParaLen != 0) { |
| // Update optional parameter length |
| cb.setByte(optParaLenIndex, (byte) (optParaLen + 2)); //+2 for optional parameter type. |
| } |
| |
| // write OPEN Object Length |
| int length = cb.writerIndex() - startIndex; |
| cb.setShort(msgLenIndex, (short) length); |
| message.bgpMsgHeader.setLength((short) length); |
| } |
| } |
| |
| /** |
| * returns length of capability tlvs. |
| * |
| * @param cb of type channel buffer |
| * @param message of type BGPOpenMsgVer4 |
| * @return capParaLen of open message |
| */ |
| protected int packCapabilityTlv(ChannelBuffer cb, BGPOpenMsgVer4 message) { |
| int startIndex = cb.writerIndex(); |
| int capParaLen = 0; |
| int capParaLenIndex = 0; |
| |
| LinkedList<BGPValueType> capabilityTlv = message.capabilityTlv; |
| ListIterator<BGPValueType> listIterator = capabilityTlv.listIterator(); |
| |
| if (listIterator.hasNext()) { |
| // Set optional parameter type as 2 |
| cb.writeByte(OPT_PARA_TYPE_CAPABILITY); |
| |
| // Store the index of capability parameter length and update length at the end |
| capParaLenIndex = cb.writerIndex(); |
| |
| // Set capability parameter length as 0 |
| cb.writeByte(0); |
| |
| // Update the startIndex to know the length of capability tlv |
| startIndex = cb.writerIndex(); |
| } |
| |
| while (listIterator.hasNext()) { |
| BGPValueType tlv = listIterator.next(); |
| if (tlv == null) { |
| log.debug("Warning: tlv is null from CapabilityTlv list"); |
| continue; |
| } |
| tlv.write(cb); |
| } |
| |
| capParaLen = cb.writerIndex() - startIndex; |
| |
| if (capParaLen != 0) { |
| // Update capability parameter length |
| cb.setByte(capParaLenIndex, (byte) capParaLen); |
| } |
| return capParaLen; |
| } |
| |
| @Override |
| public String toString() { |
| return MoreObjects.toStringHelper(getClass()) |
| .add("bgpMsgHeader", bgpMsgHeader) |
| .add("version", version) |
| .add("holdTime", holdTime) |
| .add("asNumber", asNumber) |
| .add("bgpId", bgpId) |
| .add("capabilityTlv", capabilityTlv) |
| .toString(); |
| } |
| } |