ONOS-2739 - OSPF Basic Packet Structures , which includes encoding and decoding

Change-Id: Ifaaa4d3640c6a4fec4931db54a1f03100cc9d9e6

+/*
+ * Copyright 2016 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.
+ */
+
+/**
+ * Implementation of the OSPF LSA Sub Types.
+ */
+package org.onosproject.ospf.protocol.lsa.subtypes;
\ No newline at end of file

+/*
+ * Copyright 2016 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.ospf.protocol.lsa.types;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Objects;
+import com.google.common.primitives.Bytes;
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.onosproject.ospf.controller.OspfLsaType;
+import org.onosproject.ospf.exceptions.OspfErrorType;
+import org.onosproject.ospf.exceptions.OspfParseException;
+import org.onosproject.ospf.protocol.lsa.OpaqueLsaHeader;
+import org.onosproject.ospf.protocol.lsa.TlvHeader;
+import org.onosproject.ospf.protocol.lsa.tlvtypes.LinkTlv;
+import org.onosproject.ospf.protocol.lsa.tlvtypes.OpaqueTopLevelTlvTypes;
+import org.onosproject.ospf.protocol.lsa.tlvtypes.RouterTlv;
+import org.onosproject.ospf.protocol.util.OspfParameters;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Representation of an Opaque LSA of type area local (10).
+ */
+public class OpaqueLsa10 extends OpaqueLsaHeader {
+    /*
+      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
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     |            LS age             |     Options   |   9, 10 or 11 |
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     |  Opaque Type  |               Opaque ID                       |
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     |                      Advertising Router                       |
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     |                      LS Sequence Number                       |
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     |         LS checksum           |           Length              |
+     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+     |                                                               |
+     +                                                               +
+     |                      Opaque Information                       |
+     +                                                               +
+     |                              ...                              |
+
+        Opaque LSA format
+        REFERENCE : RFC 5250
+    */
+    private List<TopLevelTlv> topLevelValues = new ArrayList<>();
+    private byte[] opaqueInfo = null;
+
+    /**
+     * Creates an instance of Opaque type 10 LSA.
+     *
+     * @param lsaHeader LSA header instance
+     */
+    public OpaqueLsa10(OpaqueLsaHeader lsaHeader) {
+        populateHeader(lsaHeader);
+    }
+
+    /**
+     * Returns the list of top level TLVs.
+     *
+     * @return list of top level TLVs
+     */
+    public List<TopLevelTlv> topLevelValues() {
+        return topLevelValues;
+    }
+
+    /**
+     * Adds TLV value.
+     *
+     * @param value TLV value
+     */
+    public void addValue(TopLevelTlv value) {
+        topLevelValues.add(value);
+    }
+
+    /**
+     * Reads from channel buffer and populate instance.
+     *
+     * @param channelBuffer channelBuffer instance
+     * @throws OspfParseException might throws exception while parsing buffer
+     */
+    public void readFrom(ChannelBuffer channelBuffer) throws OspfParseException {
+
+        try {
+            if (this.opaqueId() == OspfParameters.TRAFFIC_ENGINEERING) {
+                while (channelBuffer.readableBytes() > 0) {
+                    TlvHeader tlvHeader = new TlvHeader();
+                    tlvHeader.setTlvType(channelBuffer.readUnsignedShort());
+                    tlvHeader.setTlvLength(channelBuffer.readUnsignedShort());
+                    if (tlvHeader.tlvType() == OpaqueTopLevelTlvTypes.ROUTER.value()) {
+                        RouterTlv routerTlv = new RouterTlv(tlvHeader);
+                        routerTlv.readFrom(channelBuffer.readBytes(tlvHeader.tlvLength()));
+                        this.addValue(routerTlv);
+                    } else if (tlvHeader.tlvType() == OpaqueTopLevelTlvTypes.LINK.value()) {
+                        LinkTlv linkTlv = new LinkTlv(tlvHeader);
+                        linkTlv.readFrom(channelBuffer.readBytes(tlvHeader.tlvLength()));
+                        this.addValue(linkTlv);
+                    }
+                }
+            } else {
+                int length = channelBuffer.readableBytes();
+                opaqueInfo = new byte[length];
+                channelBuffer.readBytes(opaqueInfo, 0, length);
+            }
+
+        } catch (Exception e) {
+            log.debug("Error::OpaqueLsa10:: {}", e.getMessage());
+            throw new OspfParseException(OspfErrorType.OSPF_MESSAGE_ERROR,
+                                         OspfErrorType.BAD_MESSAGE);
+        }
+    }
+
+    /**
+     * Returns instance as bytes.
+     *
+     * @return instance as bytes
+     * @throws Exception might throws exception while parsing packet
+     */
+    public byte[] asBytes() throws Exception {
+
+        byte[] lsaMessage = null;
+        byte[] lsaHeader = getOpaqueLsaHeaderAsByteArray();
+        byte[] lsaBody = getLsaBodyAsByteArray();
+        lsaMessage = Bytes.concat(lsaHeader, lsaBody);
+        return lsaMessage;
+
+    }
+
+    /**
+     * Gets the LSA body as byte array.
+     *
+     * @return the lsa body as byte array
+     * @throws Exception might throws exception while parsing packet
+     */
+    public byte[] getLsaBodyAsByteArray() throws Exception {
+        List<Byte> bodyLst = new ArrayList<>();
+        if (this.opaqueId() == 1) {
+            for (TopLevelTlv tlv : this.topLevelValues) {
+                //Check the sub type of lsa and build bytes accordingly
+                if (tlv instanceof RouterTlv) {
+                    RouterTlv routerTlv = (RouterTlv) tlv;
+                    bodyLst.addAll(Bytes.asList(routerTlv.asBytes()));
+                } else if (tlv instanceof LinkTlv) {
+                    LinkTlv linkTlv = (LinkTlv) tlv;
+                    bodyLst.addAll(Bytes.asList(linkTlv.asBytes()));
+                }
+            }
+        } else {
+            return opaqueInfo;
+        }
+
+        return Bytes.toArray(bodyLst);
+    }
+
+    @Override
+    public OspfLsaType getOspfLsaType() {
+        return OspfLsaType.AREA_LOCAL_OPAQUE_LSA;
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .omitNullValues()
+                .add("topLevelValues", topLevelValues)
+                .add("opaqueInfo", opaqueInfo)
+                .toString();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        OpaqueLsa10 that = (OpaqueLsa10) o;
+        return Objects.equal(topLevelValues, that.topLevelValues) &&
+                Objects.equal(opaqueInfo, that.opaqueInfo);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(opaqueInfo, topLevelValues);
+    }
+}
\ No newline at end of file

+/*
+ * Copyright 2016 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.
+ */
+
+/**
+ * Implementation of the OSPF LSA types.
+ */
+package org.onosproject.ospf.protocol.lsa.types;
\ No newline at end of file

+/*
+ * Copyright 2016 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.ospf.protocol.ospfpacket;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.onlab.packet.Ip4Address;
+import org.onosproject.ospf.exceptions.OspfErrorType;
+import org.onosproject.ospf.exceptions.OspfParseException;
+import org.onosproject.ospf.protocol.ospfpacket.types.DdPacket;
+import org.onosproject.ospf.protocol.ospfpacket.types.HelloPacket;
+import org.onosproject.ospf.protocol.ospfpacket.types.LsAcknowledge;
+import org.onosproject.ospf.protocol.ospfpacket.types.LsRequest;
+import org.onosproject.ospf.protocol.ospfpacket.types.LsUpdate;
+import org.onosproject.ospf.protocol.util.OspfParameters;
+import org.onosproject.ospf.protocol.util.OspfUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A message reader which reads OSPF messages from ChannelBuffer and converts to OspfMessage instances.
+ */
+public class OspfMessageReader {
+    private static final Logger log = LoggerFactory.getLogger(OspfMessageReader.class);
+
+    /**
+     * Reads and Converts the channel buffer to OspfMessage instance.
+     *
+     * @param channelBuffer channel buffer instance.
+     * @return OSPF message instance.
+     * @throws Exception might throws exception while parsing buffer
+     */
+    public OspfMessage readFromBuffer(ChannelBuffer channelBuffer)
+            throws Exception {
+
+        if (channelBuffer.readableBytes() < OspfUtil.PACKET_MINIMUM_LENGTH) {
+            log.error("Packet should have minimum length...");
+            throw new OspfParseException(OspfErrorType.MESSAGE_HEADER_ERROR, OspfErrorType.BAD_MESSAGE_LENGTH);
+        }
+
+        try {
+            OspfPacketHeader ospfHeader = getOspfHeader(channelBuffer);
+            int len = ospfHeader.ospfPacLength() - OspfUtil.OSPF_HEADER_LENGTH;
+
+            OspfMessage ospfMessage = null;
+            switch (ospfHeader.ospfType()) {
+                case OspfParameters.HELLO:
+                    ospfMessage = new HelloPacket(ospfHeader);
+                    break;
+                case OspfParameters.DD:
+                    ospfMessage = new DdPacket(ospfHeader);
+                    break;
+                case OspfParameters.LSREQUEST:
+                    ospfMessage = new LsRequest(ospfHeader);
+                    break;
+                case OspfParameters.LSUPDATE:
+                    ospfMessage = new LsUpdate(ospfHeader);
+                    break;
+                case OspfParameters.LSACK:
+                    ospfMessage = new LsAcknowledge(ospfHeader);
+                    break;
+                default:
+                    log.debug("Message Reader[Decoder] - Unknown LSA type..!!!");
+                    break;
+            }
+
+            if (ospfMessage != null) {
+                try {
+                    log.debug("{} Received::Message Length :: {} ", ospfMessage.ospfMessageType(),
+                              ospfHeader.ospfPacLength());
+                    ospfMessage.readFrom(channelBuffer.readBytes(len));
+                } catch (Exception e) {
+                    throw new OspfParseException(OspfErrorType.OSPF_MESSAGE_ERROR,
+                                                 OspfErrorType.BAD_MESSAGE);
+                }
+
+            }
+
+            return ospfMessage;
+        } catch (Exception e) {
+            throw new OspfParseException(OspfErrorType.OSPF_MESSAGE_ERROR,
+                                         OspfErrorType.BAD_MESSAGE);
+        }
+    }
+
+    /**
+     * Gets the OSPF packet Header.
+     *
+     * @param channelBuffer channel buffer instance.
+     * @return Ospf Header instance.
+     */
+    private OspfPacketHeader getOspfHeader(ChannelBuffer channelBuffer) throws Exception {
+        OspfPacketHeader ospfPacketHeader = new OspfPacketHeader();
+
+        byte[] sourceIpBytes = new byte[OspfUtil.FOUR_BYTES];
+        channelBuffer.readBytes(sourceIpBytes, 0, OspfUtil.FOUR_BYTES);
+        Ip4Address sourceIP = Ip4Address.valueOf(sourceIpBytes);
+
+        // Determine ospf version & Packet Type
+        int version = channelBuffer.readByte(); //byte 1 is ospf version
+        int packetType = channelBuffer.readByte(); //byte 2 is ospf packet type
+
+        // byte 3 & 4 combine is packet length.
+        int packetLength = channelBuffer.readShort();
+
+        if (packetLength > channelBuffer.readableBytes() + OspfUtil.FOUR_BYTES) {
+            log.error("Packet should have minimum length...");
+            throw new OspfParseException(OspfErrorType.MESSAGE_HEADER_ERROR, OspfErrorType.BAD_MESSAGE_LENGTH);
+        }
+
+        byte[] tempByteArray = new byte[OspfUtil.FOUR_BYTES];
+        channelBuffer.readBytes(tempByteArray, 0, OspfUtil.FOUR_BYTES);
+        Ip4Address routerId = Ip4Address.valueOf(tempByteArray);
+
+        tempByteArray = new byte[OspfUtil.FOUR_BYTES];
+        channelBuffer.readBytes(tempByteArray, 0, OspfUtil.FOUR_BYTES);
+        Ip4Address areaId = Ip4Address.valueOf(tempByteArray);
+
+        int checkSum = channelBuffer.readUnsignedShort();
+        int auType = channelBuffer.readUnsignedShort();
+        int authentication = (int) channelBuffer.readLong();
+
+        ospfPacketHeader.setSourceIp(sourceIP);
+        ospfPacketHeader.setOspfVer(version);
+        ospfPacketHeader.setOspftype(packetType);
+        ospfPacketHeader.setOspfPacLength(packetLength);
+        ospfPacketHeader.setRouterId(routerId);
+        ospfPacketHeader.setAreaId(areaId);
+        ospfPacketHeader.setChecksum(checkSum);
+        ospfPacketHeader.setAuthType(auType);
+        ospfPacketHeader.setAuthentication(authentication);
+
+        return ospfPacketHeader;
+    }
+}
\ No newline at end of file

+/*
+* Copyright 2016 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.ospf.protocol.ospfpacket;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import org.onosproject.ospf.protocol.util.OspfParameters;
+import org.onosproject.ospf.protocol.util.OspfUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A message writer which writes an OspfMessage to ChannelBuffer.
+ */
+public class OspfMessageWriter {
+    private static final Logger log = LoggerFactory.getLogger(OspfMessageWriter.class);
+
+    /**
+     * Writes OSPF message to ChannelBuffer.
+     *
+     * @param ospfMessage    OSPF message
+     * @param interfaceState interface state
+     * @param interfaceType  interface type
+     * @return channelBuffer channel buffer instance
+     * @throws Exception might throws exception while parsing message
+     */
+    public ChannelBuffer writeToBuffer(OspfMessage ospfMessage, int interfaceState,
+                                       int interfaceType) throws Exception {
+
+        ChannelBuffer buf = null;
+        switch (ospfMessage.ospfMessageType().value()) {
+            case OspfParameters.HELLO:
+            case OspfParameters.LSACK:
+                buf = writeMessageToBuffer(ospfMessage, interfaceState);
+                break;
+            case OspfParameters.DD:
+            case OspfParameters.LSREQUEST:
+            case OspfParameters.LSUPDATE:
+                buf = writeMessageToBuffer(ospfMessage, interfaceState);
+                break;
+            default:
+                log.debug("Message Writer[Encoder] - Unknown Message to encode..!!!");
+                break;
+        }
+
+        return buf;
+    }
+
+    /**
+     * Writes an OSPF Message to channel buffer.
+     *
+     * @param ospfMessage    OSPF Message instance
+     * @param interfaceState interface state
+     * @return channelBuffer instance
+     */
+    private ChannelBuffer writeMessageToBuffer(OspfMessage ospfMessage, int interfaceState) throws Exception {
+        ChannelBuffer channelBuffer = null;
+        byte[] ospfMessageAsByte = ospfMessage.asBytes();
+        //Add the length and checksum in byte array at length position 2 & 3 and Checksum position
+        ospfMessageAsByte = OspfUtil.addLengthAndCheckSum(ospfMessageAsByte, OspfUtil.OSPFPACKET_LENGTH_POS1,
+                                                          OspfUtil.OSPFPACKET_LENGTH_POS2,
+                                                          OspfUtil.OSPFPACKET_CHECKSUM_POS1,
+                                                          OspfUtil.OSPFPACKET_CHECKSUM_POS2);
+        //Add Interface State Info and destination IP as metadata
+        if (interfaceState == OspfParameters.DR || interfaceState == OspfParameters.BDR) {
+            ospfMessageAsByte = OspfUtil.addMetadata(ospfMessageAsByte, OspfUtil.JOIN_ALL_DROUTERS,
+                                                     ospfMessage.destinationIp());
+        } else {
+            ospfMessageAsByte = OspfUtil.addMetadata(ospfMessageAsByte, OspfUtil.ONLY_ALL_SPF_ROUTERS,
+                                                     ospfMessage.destinationIp());
+        }
+
+        channelBuffer = ChannelBuffers.buffer(ospfMessageAsByte.length);
+        channelBuffer.writeBytes(ospfMessageAsByte);
+
+        return channelBuffer;
+    }
+}
\ No newline at end of file

+/*
+ * Copyright 2016 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.ospf.protocol.lsa.types;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onlab.packet.Ip4Address;
+import org.onosproject.ospf.controller.OspfLsaType;
+import org.onosproject.ospf.protocol.lsa.OpaqueLsaHeader;
+import org.onosproject.ospf.protocol.lsa.TlvHeader;
+import org.onosproject.ospf.protocol.lsa.tlvtypes.LinkTlv;
+import org.onosproject.ospf.protocol.lsa.tlvtypes.RouterTlv;
+
+
+import java.util.List;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+
+/**
+ * Unit test class for OpaqueLsa10.
+ */
+public class OpaqueLsa10Test {
+
+    private final byte[] packet = {0, 1, 0, 4, 1, 1, 1, 1, 0, 2, 0, 84, 0, 0, 0,
+            0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+    private OpaqueLsa10 opaqueLsa10;
+    private TopLevelTlv tlv;
+    private OpaqueLsaHeader opqueHeader;
+    private ChannelBuffer channelBuffer;
+    private byte[] result;
+    private RouterTlv routerTlv;
+    private RouterTlv routerTlv1;
+    private LinkTlv linkTlv;
+    private LinkTlv linkTlv1;
+    private OspfLsaType ospflsaType;
+    private int result1;
+    private List result2;
+
+    @Before
+    public void setUp() throws Exception {
+        opaqueLsa10 = new OpaqueLsa10(new OpaqueLsaHeader());
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        opaqueLsa10 = null;
+        tlv = null;
+        opqueHeader = null;
+        channelBuffer = null;
+        result = null;
+        routerTlv = null;
+        routerTlv1 = null;
+        linkTlv1 = null;
+        ospflsaType = null;
+    }
+
+    /**
+     * Tests to string method.
+     */
+    @Test
+    public void testToString() throws Exception {
+        assertThat(opaqueLsa10.toString(), is(notNullValue()));
+    }
+
+    /**
+     * Tests addValue() method.
+     */
+    @Test
+    public void testAddValue() throws Exception {
+        tlv = new RouterTlv(new TlvHeader());
+        opaqueLsa10.addValue(tlv);
+        assertThat(opaqueLsa10, is(notNullValue()));
+    }
+
+    /**
+     * Tests readFrom() method.
+     */
+    @Test(expected = Exception.class)
+    public void testReadFrom() throws Exception {
+        opqueHeader = new OpaqueLsaHeader();
+        opqueHeader.setLsType(10);
+        opqueHeader.setLsPacketLen(48);
+        opqueHeader.setLsCheckSum(10);
+        opqueHeader.setAge(4);
+        opqueHeader.setOpaqueId(1);
+        opqueHeader.setOpaqueType(10);
+        opqueHeader.setLsSequenceNo(250);
+        opqueHeader.setAdvertisingRouter(Ip4Address.valueOf("100.226.165.165"));
+        opqueHeader.setOptions(66);
+        opaqueLsa10 = new OpaqueLsa10(opqueHeader);
+        channelBuffer = ChannelBuffers.copiedBuffer(packet);
+        opaqueLsa10.readFrom(channelBuffer);
+        result = opaqueLsa10.asBytes();
+        assertThat(result, is(notNullValue()));
+    }
+
+    /**
+     * Tests asBytes() method.
+     */
+    @Test(expected = Exception.class)
+    public void testAsBytes() throws Exception {
+        opqueHeader = new OpaqueLsaHeader();
+        opqueHeader.setLsType(10);
+        opqueHeader.setLsPacketLen(48);
+        opqueHeader.setLsCheckSum(10);
+        opqueHeader.setAge(4);
+        opqueHeader.setOpaqueId(1);
+        opqueHeader.setOpaqueType(10);
+        opqueHeader.setLsSequenceNo(250);
+        opqueHeader.setAdvertisingRouter(Ip4Address.valueOf("100.226.165.165"));
+        opqueHeader.setOptions(66);
+        opaqueLsa10 = new OpaqueLsa10(opqueHeader);
+        channelBuffer = ChannelBuffers.copiedBuffer(packet);
+        opaqueLsa10.readFrom(channelBuffer);
+        result = opaqueLsa10.getLsaBodyAsByteArray();
+        result = opaqueLsa10.asBytes();
+        assertThat(result, is(notNullValue()));
+    }
+
+    /**
+     * Tests getLsaBodyAsByteArray() method.
+     */
+    @Test(expected = Exception.class)
+    public void testGetLsaBodyAsByteArray() throws Exception {
+        opqueHeader = new OpaqueLsaHeader();
+        opqueHeader.setLsType(10);
+        opqueHeader.setLsPacketLen(48);
+        opqueHeader.setLsCheckSum(10);
+        opqueHeader.setAge(4);
+        opqueHeader.setOpaqueId(1);
+        opqueHeader.setOpaqueType(10);
+        opqueHeader.setLsSequenceNo(250);
+        opqueHeader.setAdvertisingRouter(Ip4Address.valueOf("100.226.165.165"));
+        opqueHeader.setOptions(2);
+        opaqueLsa10 = new OpaqueLsa10(opqueHeader);
+        routerTlv = new RouterTlv(new TlvHeader());
+        linkTlv = new LinkTlv(new TlvHeader());
+        opaqueLsa10.addValue(routerTlv);
+        opaqueLsa10.addValue(linkTlv);
+        routerTlv1 = new RouterTlv(new TlvHeader());
+        linkTlv1 = new LinkTlv(new TlvHeader());
+        opaqueLsa10.addValue(routerTlv1);
+        opaqueLsa10.addValue(linkTlv1);
+        channelBuffer = ChannelBuffers.copiedBuffer(packet);
+        opaqueLsa10.readFrom(channelBuffer);
+        result = opaqueLsa10.getLsaBodyAsByteArray();
+        assertThat(result, is(notNullValue()));
+    }
+
+    /**
+     * Tests getLsaBodyAsByteArray() method.
+     */
+    @Test(expected = Exception.class)
+    public void testGetLsaBodyAsByteArray1() throws Exception {
+        opqueHeader = new OpaqueLsaHeader();
+        opqueHeader.setLsType(10);
+        opqueHeader.setLsPacketLen(48);
+        opqueHeader.setLsCheckSum(10);
+        opqueHeader.setAge(4);
+        opqueHeader.setOpaqueId(1);
+        opqueHeader.setOpaqueType(10);
+        opqueHeader.setLsSequenceNo(250);
+        opqueHeader.setAdvertisingRouter(Ip4Address.valueOf("100.226.165.165"));
+        opqueHeader.setOptions(2);
+        opaqueLsa10 = new OpaqueLsa10(opqueHeader);
+        routerTlv = new RouterTlv(new TlvHeader());
+        opaqueLsa10.addValue(routerTlv);
+        channelBuffer = ChannelBuffers.copiedBuffer(packet);
+        result = opaqueLsa10.getLsaBodyAsByteArray();
+        assertThat(result, is(notNullValue()));
+    }
+
+    /**
+     * Tests getLsaBodyAsByteArray() method.
+     */
+    @Test(expected = Exception.class)
+    public void testGetLsaBodyAsByteArray2() throws Exception {
+        opqueHeader = new OpaqueLsaHeader();
+        opqueHeader.setLsType(10);
+        opqueHeader.setLsPacketLen(48);
+        opqueHeader.setLsCheckSum(10);
+        opqueHeader.setAge(4);
+        opqueHeader.setOpaqueId(1);
+        opqueHeader.setOpaqueType(10);
+        opqueHeader.setLsSequenceNo(250);
+        opqueHeader.setAdvertisingRouter(Ip4Address.valueOf("100.226.165.165"));
+        opqueHeader.setOptions(2);
+        opaqueLsa10 = new OpaqueLsa10(opqueHeader);
+        linkTlv = new LinkTlv(new TlvHeader());
+        opaqueLsa10.addValue(linkTlv);
+        channelBuffer = ChannelBuffers.copiedBuffer(packet);
+        opaqueLsa10.readFrom(channelBuffer);
+        result = opaqueLsa10.getLsaBodyAsByteArray();
+        assertThat(result, is(notNullValue()));
+    }
+
+    /**
+     * Tests getOspfLsaType() getter method.
+     */
+    @Test
+    public void testGetOspfLsaType() throws Exception {
+        opaqueLsa10.setLsType(10);
+        ospflsaType = opaqueLsa10.getOspfLsaType();
+        assertThat(ospflsaType, is(notNullValue()));
+        assertThat(ospflsaType, is(OspfLsaType.AREA_LOCAL_OPAQUE_LSA));
+    }
+
+    /**
+     * Tests hashCode() method.
+     */
+    @Test
+    public void testHashcode() throws Exception {
+
+        result1 = opaqueLsa10.hashCode();
+        assertThat(result1, is(notNullValue()));
+
+    }
+
+    /**
+     * Tests topLevelValues() method.
+     */
+    @Test
+    public void testTopLevelValues() throws Exception {
+
+        result2 = opaqueLsa10.topLevelValues();
+        assertThat(result2, is(notNullValue()));
+
+    }
+
+}
\ No newline at end of file

+/*
+ * Copyright 2016 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.ospf.protocol.lsa.types;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onlab.packet.Ip4Address;
+import org.onosproject.ospf.controller.OspfLsaType;
+import org.onosproject.ospf.protocol.lsa.LsaHeader;
+import org.onosproject.ospf.protocol.lsa.subtypes.OspfLsaLink;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.*;
+
+/**
+ * Unit test class for RouterLsa.
+ */
+public class RouterLsaTest {
+
+    private RouterLsa routerLsa;
+    private int result1;
+    private OspfLsaLink ospflsaLink;
+    private byte[] inputArray;
+    private LsaHeader lsaHeader;
+    private ChannelBuffer channelBuffer;
+    private byte[] result2;
+    private OspfLsaType result3;
+
+    @Before
+    public void setUp() throws Exception {
+        routerLsa = new RouterLsa();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        routerLsa = null;
+        ospflsaLink = null;
+        inputArray = null;
+        lsaHeader = null;
+        channelBuffer = null;
+        result2 = null;
+        result3 = null;
+    }
+
+
+    /**
+     * Tests virtualEndPoint() setter method.
+     */
+    @Test
+    public void testSetVirtualEndPoint() throws Exception {
+        routerLsa.setVirtualEndPoint(true);
+        assertThat(routerLsa, is(notNullValue()));
+    }
+
+
+    /**
+     * Tests isAsBoundaryRouter() setter method.
+     */
+    @Test
+    public void testSetAsBoundaryRouter() throws Exception {
+        routerLsa.setAsBoundaryRouter(true);
+        assertThat(routerLsa, is(notNullValue()));
+    }
+
+    /**
+     * Tests areaBorderRouter() setter method.
+     */
+    @Test
+    public void testSetAreaBorderRouter() throws Exception {
+        routerLsa.setAreaBorderRouter(true);
+        assertThat(routerLsa, is(notNullValue()));
+    }
+
+    /**
+     * Tests noLink() getter method.
+     */
+    @Test
+    public void testGetNoLink() throws Exception {
+        routerLsa.setNoLink(10);
+        result1 = routerLsa.noLink();
+        assertThat(result1, is(10));
+    }
+
+    /**
+     * Tests noLink() setter method.
+     */
+    @Test
+    public void testSetNoLink() throws Exception {
+        routerLsa.setNoLink(10);
+        result1 = routerLsa.noLink();
+        assertThat(result1, is(10));
+    }
+
+    /**
+     * Tests addRouterLink() method.
+     */
+    @Test
+    public void testAddRouterLink() throws Exception {
+        routerLsa.setNoLink(0);
+        ospflsaLink = createOspfLsaLink();
+        routerLsa.addRouterLink(ospflsaLink);
+        routerLsa.incrementLinkNo();
+        result1 = routerLsa.noLink();
+        assertThat(result1, is(1));
+
+    }
+
+
+    /**
+     * Tests readFrom() method.
+     */
+    @Test
+    public void testReadFrom() throws Exception {
+        ospflsaLink = createOspfLsaLink();
+        routerLsa.addRouterLink(ospflsaLink);
+        inputArray = createByteForRouterLsa();
+        lsaHeader = createLsaHeader();
+        routerLsa = new RouterLsa(lsaHeader);
+        channelBuffer = ChannelBuffers.copiedBuffer(inputArray);
+        routerLsa.readFrom(channelBuffer);
+        assertThat(routerLsa, is(notNullValue()));
+    }
+
+    /**
+     * Tests readFrom() method.
+     */
+    @Test(expected = Exception.class)
+    public void testReadFrom1() throws Exception {
+        byte[] temp = {0, 0, 0};
+        ospflsaLink = createOspfLsaLink();
+        routerLsa.addRouterLink(ospflsaLink);
+        inputArray = temp;
+        lsaHeader = createLsaHeader();
+        routerLsa = new RouterLsa(lsaHeader);
+        channelBuffer = ChannelBuffers.copiedBuffer(inputArray);
+        routerLsa.readFrom(channelBuffer);
+        assertThat(routerLsa, is(notNullValue()));
+    }
+
+    /**
+     * Tests asBytes() method.
+     */
+    @Test
+    public void testAsBytes() throws Exception {
+        result2 = routerLsa.asBytes();
+        assertThat(result2, is(notNullValue()));
+    }
+
+    /**
+     * Tests getLsaBodyAsByteArray() method.
+     */
+    @Test
+    public void testGetLsaBodyAsByteArray() throws Exception {
+        routerLsa.setAreaBorderRouter(true);
+        routerLsa.setVirtualEndPoint(true);
+        routerLsa.setAreaBorderRouter(true);
+        ospflsaLink = createOspfLsaLink();
+        routerLsa.addRouterLink(ospflsaLink);
+        result2 = routerLsa.getLsaBodyAsByteArray();
+        assertThat(result2, is(notNullValue()));
+    }
+
+    /**
+     * Tests getOspfLsaType() getter method.
+     */
+    @Test
+    public void testGetOspfLsaType() throws Exception {
+        routerLsa.setLsType(1);
+        result3 = routerLsa.getOspfLsaType();
+        assertThat(result3, is(OspfLsaType.ROUTER));
+    }
+
+    /**
+     * Tests incrementLinkNo() method.
+     */
+    @Test
+    public void testIncrementLinkNo() throws Exception {
+        routerLsa.setNoLink(1);
+        routerLsa.incrementLinkNo();
+        assertThat(routerLsa.noLink(), is(2));
+    }
+
+    /**
+     * Tests lsaHeader() method.
+     */
+    @Test
+    public void testGetLsaHeader() throws Exception {
+        lsaHeader = (LsaHeader) routerLsa.lsaHeader();
+        assertThat(lsaHeader, instanceOf(RouterLsa.class));
+    }
+
+    /**
+     * Tests to string method.
+     */
+    @Test
+    public void testToString() throws Exception {
+        assertThat(routerLsa.toString(), is(notNullValue()));
+
+    }
+
+    /**
+     * Utility method used by junit methods.
+     */
+    private OspfLsaLink createOspfLsaLink() {
+        ospflsaLink = new OspfLsaLink();
+        ospflsaLink.setLinkId("10.226.165.164");
+        ospflsaLink.setMetric(10);
+        ospflsaLink.setTos(50);
+        ospflsaLink.setLinkType(2);
+        ospflsaLink.setLinkData("10.226.165.170");
+        return ospflsaLink;
+    }
+
+    /**
+     * Utility method used by junit methods.
+     */
+    private byte[] createByteForRouterLsa() {
+        byte[] packet = {2, 1, 1, 52, -64, -88, 56, 1, -64, -88, 56, 1, 0, 100, 0, 100, 0, 0, 0, 0, 0, 0, 0, 0, -64,
+                -88, 56, 1, 0, 10, 1, 1, 0, 0, 0, 40, -64, -88, 56, 1, -64, -88, 56, 1, -64, -88, 56, 1, -64, -88, 56,
+                1};
+        return packet;
+    }
+
+    /**
+     * Utility method used by junit methods.
+     */
+    private LsaHeader createLsaHeader() {
+        lsaHeader = new LsaHeader();
+        lsaHeader.setLsType(1);
+        lsaHeader.setLsPacketLen(48);
+        lsaHeader.setLsCheckSum(10);
+        lsaHeader.setAge(4);
+        lsaHeader.setLinkStateId("10.226.165.164");
+        lsaHeader.setLsSequenceNo(250);
+        lsaHeader.setAdvertisingRouter(Ip4Address.valueOf("100.226.165.165"));
+        lsaHeader.setOptions(2);
+        return lsaHeader;
+    }
+
+    /**
+     * Tests hashcode() method.
+     */
+    @Test
+    public void testHashcode() throws Exception {
+
+        result1 = routerLsa.hashCode();
+        assertThat(result1, is(notNullValue()));
+
+    }
+}

+/*
+ * Copyright 2016 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.ospf.protocol.ospfpacket;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.notNullValue;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * Unit test class for OspfMessageReader.
+ */
+
+public class OspfMessageReaderTest {
+
+    private final byte[] packet1 = {1, 1, 1, 1, 2, 1, 0, 44, -64, -88, -86, 8,
+            0, 0, 0, 1, 39, 59, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -1, 0, 0,
+            10, 2, 1, 0, 0, 0, 40, -64, -88, -86, 8, 0, 0, 0, 0};
+    private final byte[] packet2 = {1, 1, 1, 1, 2, 2, 0, 52, -64, -88, -86, 8, 0,
+            0, 0, 1, -96, 82, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, -36, 2, 7, 65, 119,
+            -87, 126, 0, 23, 2, 1, 10, 10, 10, 10, 10, 10, 10, 10, -128, 0, 0, 6,
+            -69, 26, 0, 36};
+    private final byte[] packet3 = {1, 1, 1, 1, 2, 3, 0, 36, -64, -88, -86, 3, 0,
+            0, 0, 1, -67, -57, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -64, -88,
+            -86, 8, -64, -88, -86, 8};
+    private final byte[] packet4 = {1, 1, 1, 1, 2, 4, 1, 36, -64, -88, -86, 3, 0,
+            0, 0, 1, 54, 107, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, 0,
+            2, 2, 1, -64, -88, -86, 3, -64, -88, -86, 3, -128, 0
+            , 0, 1, 58, -100, 0, 48, 2, 0, 0, 2, -64, -88, -86
+            , 0, -1, -1, -1, 0, 3, 0, 0, 10, -64, -88, -86, 0,
+            -1, -1, -1, 0, 3, 0, 0, 10, 0, 3, 2, 5, 80, -44,
+            16, 0, -64, -88, -86, 2, -128, 0, 0, 1, 42, 73, 0,
+            36, -1, -1, -1, -1, -128, 0, 0, 20, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 3, 2, 5, -108, 121, -85, 0, -64, -88,
+            -86, 2, -128, 0, 0, 1, 52, -91, 0, 36, -1, -1, -1,
+            0, -128, 0, 0, 20, -64, -88, -86, 1, 0, 0, 0, 0, 0,
+            3, 2, 5, -64, -126, 120, 0, -64, -88, -86, 2, -128, 0,
+            0, 1, -45, 25, 0, 36, -1, -1, -1, 0, -128, 0, 0, 20,
+            0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 5, -64, -88, 0, 0,
+            -64, -88, -86, 2, -128, 0, 0, 1, 55, 8, 0, 36, -1, -1
+            , -1, 0, -128, 0, 0, 20, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            3, 2, 5, -64, -88, 1, 0, -64, -88, -86, 2, -128, 0, 0,
+            1, 44, 18, 0, 36, -1, -1, -1, 0, -128, 0, 0, 20, 0, 0,
+            0, 0, 0, 0, 0, 0, 0, 3, 2, 5, -64, -88, -84, 0, -64,
+            -88, -86, 2, -128, 0, 0, 1, 51, 65, 0, 36, -1, -1, -1, 0,
+            -128, 0, 0, 20, -64, -88, -86, 10, 0, 0, 0, 0};
+    private final byte[] packet5 = {1, 1, 1, 1, 2, 5, 0, 44, -64, -88, -86, 8, 0, 0,
+            0, 1, -30, -12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 14, 16, 2, 1, -64, -88, -86,
+            2, -64, -88, -86, 2, -128, 0, 0, 1, 74, -114, 0, 48};
+    private OspfMessageReader ospfMessageReader;
+    private ChannelBuffer channelBuffer;
+
+    @Before
+    public void setUp() throws Exception {
+        ospfMessageReader = new OspfMessageReader();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        ospfMessageReader = null;
+        channelBuffer = null;
+    }
+
+    /**
+     * Tests readFromBuffer() method.
+     */
+    @Test
+    public void testReadFromBuffer() throws Exception {
+        channelBuffer = ChannelBuffers.copiedBuffer(packet1);
+        ospfMessageReader.readFromBuffer(channelBuffer);
+
+        channelBuffer = ChannelBuffers.copiedBuffer(packet2);
+        ospfMessageReader.readFromBuffer(channelBuffer);
+
+        channelBuffer = ChannelBuffers.copiedBuffer(packet3);
+        ospfMessageReader.readFromBuffer(channelBuffer);
+
+        channelBuffer = ChannelBuffers.copiedBuffer(packet4);
+        ospfMessageReader.readFromBuffer(channelBuffer);
+
+        channelBuffer = ChannelBuffers.copiedBuffer(packet5);
+        ospfMessageReader.readFromBuffer(channelBuffer);
+        assertThat(ospfMessageReader, is(notNullValue()));
+
+    }
+}

+/*
+ * Copyright 2016 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.ospf.protocol.ospfpacket;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onlab.packet.Ip4Address;
+import org.onosproject.ospf.protocol.ospfpacket.types.DdPacket;
+import org.onosproject.ospf.protocol.ospfpacket.types.HelloPacket;
+import org.onosproject.ospf.protocol.ospfpacket.types.LsAcknowledge;
+import org.onosproject.ospf.protocol.ospfpacket.types.LsRequest;
+import org.onosproject.ospf.protocol.ospfpacket.types.LsUpdate;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.notNullValue;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Unit test class for OspfMessageWriter.
+ */
+public class OspfMessageWriterTest {
+
+    private OspfMessageWriter ospfMessageWriter;
+    private HelloPacket helloPacket;
+    private DdPacket ddPacket;
+    private LsAcknowledge lsAck;
+    private LsRequest lsReq;
+    private LsUpdate lsUpdate;
+
+    @Before
+    public void setUp() throws Exception {
+        ospfMessageWriter = new OspfMessageWriter();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        ospfMessageWriter = null;
+        helloPacket = null;
+        ddPacket = null;
+        lsAck = null;
+        lsReq = null;
+        lsUpdate = null;
+    }
+
+    /**
+     * Tests writeToBuffer() method.
+     */
+    @Test
+    public void testWriteToBuffer() throws Exception {
+        helloPacket = new HelloPacket();
+        helloPacket.setAuthType(1);
+        helloPacket.setOspftype(1);
+        helloPacket.setRouterId(Ip4Address.valueOf("10.226.165.164"));
+        helloPacket.setAreaId(Ip4Address.valueOf("10.226.165.100"));
+        helloPacket.setChecksum(201);
+        helloPacket.setAuthentication(2);
+        helloPacket.setOspfPacLength(48);
+        helloPacket.setOspfVer(2);
+        helloPacket.setNetworkMask(Ip4Address.valueOf("255.255.255.255"));
+        helloPacket.setOptions(2); //not setting now
+        helloPacket.setHelloInterval(10);
+        helloPacket.setRouterPriority(1);
+        helloPacket.setRouterDeadInterval(40);
+        helloPacket.setDr(Ip4Address.valueOf("1.1.1.1"));
+        helloPacket.setBdr(Ip4Address.valueOf("2.2.2.2"));
+        helloPacket.addNeighbor(Ip4Address.valueOf("8.8.8.8"));
+        helloPacket.setDestinationIp(Ip4Address.valueOf("5.5.5.5"));
+        ospfMessageWriter.writeToBuffer(helloPacket, 7, 1);
+        assertThat(ospfMessageWriter, is(notNullValue()));
+    }
+
+    @Test(expected = Exception.class)
+    public void testWriteToBuffer1() throws Exception {
+
+        ddPacket = new DdPacket();
+        ddPacket.setAuthType(1);
+        ddPacket.setOspftype(2);
+        ddPacket.setRouterId(Ip4Address.valueOf("10.226.165.164"));
+        ddPacket.setAreaId(Ip4Address.valueOf("10.226.165.100"));
+        ddPacket.setChecksum(201);
+        ddPacket.setAuthentication(2);
+        ddPacket.setOspfPacLength(48);
+        ddPacket.setOspfVer(2);
+        ospfMessageWriter.writeToBuffer(ddPacket, 1, 1);
+        assertThat(ospfMessageWriter, is(notNullValue()));
+    }
+
+    @Test(expected = Exception.class)
+    public void testWriteToBuffer2() throws Exception {
+
+        lsAck = new LsAcknowledge();
+        lsAck.setAuthType(1);
+        lsAck.setOspftype(5);
+        lsAck.setRouterId(Ip4Address.valueOf("10.226.165.164"));
+        lsAck.setAreaId(Ip4Address.valueOf("10.226.165.100"));
+        lsAck.setChecksum(201);
+        lsAck.setAuthentication(2);
+        lsAck.setOspfPacLength(48);
+        lsAck.setOspfVer(2);
+        ospfMessageWriter.writeToBuffer(lsAck, 1, 1);
+        assertThat(ospfMessageWriter, is(notNullValue()));
+    }
+
+    @Test(expected = Exception.class)
+    public void testWriteToBuffer3() throws Exception {
+        lsReq = new LsRequest();
+        lsReq.setAuthType(1);
+        lsReq.setOspftype(3);
+        lsReq.setRouterId(Ip4Address.valueOf("10.226.165.164"));
+        lsReq.setAreaId(Ip4Address.valueOf("10.226.165.100"));
+        lsReq.setChecksum(201);
+        lsReq.setAuthentication(2);
+        lsReq.setOspfPacLength(48);
+        lsReq.setOspfVer(2);
+        ospfMessageWriter.writeToBuffer(lsReq, 1, 1);
+        assertThat(ospfMessageWriter, is(notNullValue()));
+    }
+
+    @Test(expected = Exception.class)
+    public void testWriteToBuffer4() throws Exception {
+        lsUpdate = new LsUpdate();
+        lsUpdate.setAuthType(1);
+        lsUpdate.setOspftype(3);
+        lsUpdate.setRouterId(Ip4Address.valueOf("10.226.165.164"));
+        lsUpdate.setAreaId(Ip4Address.valueOf("10.226.165.100"));
+        lsUpdate.setChecksum(201);
+        lsUpdate.setAuthentication(2);
+        lsUpdate.setOspfPacLength(48);
+        lsUpdate.setOspfVer(2);
+        ospfMessageWriter.writeToBuffer(lsUpdate, 1, 1);
+        assertThat(ospfMessageWriter, is(notNullValue()));
+    }
+
+    /**
+     * Tests writeToBuffer() method.
+     */
+    @Test(expected = Exception.class)
+    public void testWriteToBuffer5() throws Exception {
+        lsAck = new LsAcknowledge();
+        lsAck.setAuthType(1);
+        lsAck.setOspftype(5);
+        lsAck.setRouterId(Ip4Address.valueOf("10.226.165.164"));
+        lsAck.setAreaId(Ip4Address.valueOf("10.226.165.100"));
+        lsAck.setChecksum(201);
+        lsAck.setAuthentication(2);
+        lsAck.setOspfPacLength(48);
+        lsAck.setOspfVer(2);
+        ospfMessageWriter.writeToBuffer(lsAck, 1, 1);
+    }
+}
\ No newline at end of file