[CORD-2182] Implement packet serializer/deserializer for Routing Information Protocol (RIP)

Change-Id: If80af0b04a86972b91e6a9d9731864ff35c833e4
diff --git a/utils/misc/src/main/java/org/onlab/packet/RIPV2Entry.java b/utils/misc/src/main/java/org/onlab/packet/RIPV2Entry.java
new file mode 100644
index 0000000..20d54e5
--- /dev/null
+++ b/utils/misc/src/main/java/org/onlab/packet/RIPV2Entry.java
@@ -0,0 +1,238 @@
+/*
+ * Copyright 2017-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 org.onlab.packet;
+
+import org.slf4j.Logger;
+
+import java.nio.ByteBuffer;
+import java.util.Objects;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/*
+ * Entry for RIP version 2 - RFC 2453
+ */
+public class RIPV2Entry extends BasePacket {
+    public static final int ENTRY_LEN = 20;
+    public static final short AFI_IP = 2;
+    public static final byte INFINITY_METRIC = 16;
+    public static final byte NEXTHOP_METRIC =  -128; // actually it is 0xFF
+
+    private final Logger log = getLogger(getClass());
+    protected short addressFamilyId;
+    protected short routeTag;
+    protected Ip4Address ipAddress;
+    protected Ip4Address subnetMask;
+    protected Ip4Address nextHop;
+    protected int metric;
+
+    @Override
+    public byte[] serialize() {
+        ByteBuffer byteBuffer;
+        byteBuffer = ByteBuffer.allocate(ENTRY_LEN);
+        byteBuffer.putShort(addressFamilyId);
+        byteBuffer.putShort(routeTag);
+        byteBuffer.putInt(ipAddress.toInt());
+        byteBuffer.putInt(subnetMask.toInt());
+        byteBuffer.putInt(nextHop.toInt());
+        byteBuffer.putInt(metric);
+        return byteBuffer.array();
+    }
+
+    /**
+     * Deserializer function for RIPv2 entry.
+     *
+     * @return deserializer function
+     */
+    public static Deserializer<RIPV2Entry> deserializer() {
+        return (data, offset, length) -> {
+            RIPV2Entry ripEntry = new RIPV2Entry();
+
+            checkNotNull(data);
+
+            if (offset < 0 || length < 0 ||
+                length > data.length || offset >= data.length ||
+                offset + length > data.length) {
+               throw new DeserializationException("Illegal offset or length");
+            }
+            ByteBuffer bb = ByteBuffer.wrap(data, offset, length);
+            if (bb.remaining() < ENTRY_LEN) {
+               throw new DeserializationException(
+                          "Buffer underflow while reading RIP entry");
+            }
+            ripEntry.addressFamilyId = bb.getShort();
+            // skip the authentication entry
+            if (ripEntry.addressFamilyId == 0xffff) {
+                return ripEntry;
+            }
+            ripEntry.routeTag = bb.getShort();
+            ripEntry.ipAddress = Ip4Address.valueOf(bb.getInt());
+            ripEntry.subnetMask = Ip4Address.valueOf(bb.getInt());
+            ripEntry.nextHop = Ip4Address.valueOf(bb.getInt());
+            ripEntry.metric = bb.getInt();
+            return ripEntry;
+        };
+    }
+    /*
+     * (non-Javadoc)
+     *
+     * @see java.lang.Object#hashCode()
+     */
+    @Override
+    public int hashCode() {
+        return Objects.hash(super.hashCode(), nextHop.toInt(), subnetMask.toInt(),
+                            ipAddress.toInt(), addressFamilyId, metric, routeTag);
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see java.lang.Object#equals(java.lang.Object)
+     */
+    @Override
+    public boolean equals(final Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (!(obj instanceof RIPV2Entry)) {
+            return false;
+        }
+        final RIPV2Entry that = (RIPV2Entry) obj;
+
+
+        return super.equals(that) &&
+                Objects.equals(routeTag, that.routeTag) &&
+                Objects.equals(metric, that.metric) &&
+                Objects.equals(addressFamilyId, that.addressFamilyId) &&
+                Objects.equals(ipAddress, that.ipAddress) &&
+                Objects.equals(nextHop, that.nextHop) &&
+                Objects.equals(subnetMask, that.subnetMask);
+    }
+
+
+    /**
+     * @return the Address Family Identifier
+     */
+    public short getAddressFamilyId() {
+        return this.addressFamilyId;
+    }
+
+    /**
+     * @param addressFamilyIdentifier the address family identifier to set
+     * @return this
+     */
+    public RIPV2Entry setAddressFamilyId(final short addressFamilyIdentifier) {
+        this.addressFamilyId = addressFamilyIdentifier;
+        return this;
+    }
+
+    /**
+     * @return the route tag
+     */
+    public short getRouteTag() {
+        return this.routeTag;
+    }
+
+    /**
+     * @param routetag the route tag to set
+     * @return this
+     */
+    public RIPV2Entry setRouteTag(final short routetag) {
+        this.routeTag = routetag;
+        return this;
+    }
+
+    /**
+     * @return the ip address
+     */
+    public Ip4Address getipAddress() {
+        return this.ipAddress;
+    }
+
+    /**
+     * @param ipaddress the Ip Address  to set
+     * @return this
+     */
+    public RIPV2Entry setIpAddress(final Ip4Address ipaddress) {
+        this.ipAddress = ipaddress;
+        return this;
+    }
+    /**
+     * @return the subnet mask
+     */
+    public Ip4Address getSubnetMask() {
+        return this.subnetMask;
+    }
+
+    /**
+     * @param subnetmask the subnet mask  to set
+     * @return this
+     */
+    public RIPV2Entry setSubnetMask(final Ip4Address subnetmask) {
+        this.subnetMask = subnetmask;
+        return this;
+    }
+
+    /**
+     * @return the next hop
+     */
+    public Ip4Address getNextHop() {
+        return this.nextHop;
+    }
+
+    /**
+     * @param nexthop the ip address if the next hop  to set
+     * @return this
+     */
+    public RIPV2Entry setNextHop(final Ip4Address nexthop) {
+        this.nextHop = nexthop;
+        return this;
+    }
+
+
+    /**
+     * @return the metric
+     */
+    public int getMetric() {
+        return this.metric;
+    }
+
+    /**
+     * @param metric the route metric to set
+     * @return this
+     */
+    public RIPV2Entry setMetric(final int metric) {
+        this.metric = metric;
+        return this;
+    }
+
+    /*
+     * (non-Javadoc)
+     *
+     * @see java.lang.Object#toString()
+     */
+    @Override
+    public String toString() {
+        return "RIPV2Entry [address family Id=" + this.addressFamilyId + ", route tag=" + this.routeTag
+                + ", Address=" + this.ipAddress
+                + ", Subnet mask=" + this.subnetMask
+                + ", Mext hop=" + this.nextHop
+                + ", metric = " + this.metric + "]";
+    }
+}