[CORD-1616] Supports PD by DHCP relay App
Change-Id: I9a23534023ca2847bd3f77a3f9ee2b468c5bb422
diff --git a/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/FpmHeader.java b/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/FpmHeader.java
new file mode 100644
index 0000000..607c9e1
--- /dev/null
+++ b/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/FpmHeader.java
@@ -0,0 +1,172 @@
+/*
+ * 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.onosproject.routing.fpm.protocol;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.collect.ImmutableSet;
+import org.onlab.packet.DeserializationException;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.jboss.netty.buffer.ChannelBuffers;
+import java.nio.ByteBuffer;
+
+import static org.onlab.packet.PacketUtils.checkInput;
+
+/**
+ * FPM header.
+ */
+public final class FpmHeader {
+ public static final int FPM_HEADER_LENGTH = 4;
+ public static final int FPM_MESSAGE_MAX_LENGTH = 4096;
+
+ public static final short FPM_VERSION_1 = 1;
+ public static final short FPM_VERSION_ONOS_EXT = 32;
+
+ private static final ImmutableSet<Short> SUPPORTED_VERSIONS =
+ ImmutableSet.<Short>builder()
+ .add(FPM_VERSION_1)
+ .add(FPM_VERSION_ONOS_EXT)
+ .build();
+
+ public static final short FPM_TYPE_NETLINK = 1;
+ public static final short FPM_TYPE_PROTOBUF = 2;
+ public static final short FPM_TYPE_KEEPALIVE = 32;
+
+ private static final String VERSION_NOT_SUPPORTED = "FPM version not supported: ";
+ private static final String TYPE_NOT_SUPPORTED = "FPM type not supported: ";
+
+ private final short version;
+ private final short type;
+ private final int length;
+
+ private final Netlink netlink;
+
+ /**
+ * Class constructor.
+ *
+ * @param version version
+ * @param type type
+ * @param length length
+ * @param netlink netlink header
+ */
+ public FpmHeader(short version, short type, int length, Netlink netlink) {
+ this.version = version;
+ this.type = type;
+ this.length = length;
+ this.netlink = netlink;
+ }
+
+ /**
+ * Returns the protocol version.
+ *
+ * @return protocol version
+ */
+ public short version() {
+ return version;
+ }
+
+ /**
+ * Returns the type.
+ *
+ * @return type
+ */
+ public short type() {
+ return type;
+ }
+
+ /**
+ * Returns the message length.
+ *
+ * @return message length
+ */
+ public int length() {
+ return length;
+ }
+
+ /**
+ * Returns the netlink header.
+ *
+ * @return netlink header
+ */
+ public Netlink netlink() {
+ return netlink;
+ }
+
+ @Override
+ public String toString() {
+ return MoreObjects.toStringHelper(getClass())
+ .add("version", version)
+ .add("type", type)
+ .add("length", length)
+ .add("netlink", netlink)
+ .toString();
+ }
+
+ /**
+ * Decodes an FPM header from an input buffer.
+ *
+ * @param buffer input buffer
+ * @param start starting position the FPM header
+ * @param length length of the message
+ * @return FPM header
+ * @throws DeserializationException if an FPM header could not be decoded
+ * from the input buffer
+ */
+ public static FpmHeader decode(byte[] buffer, int start, int length) throws
+ DeserializationException {
+ checkInput(buffer, start, length, FPM_HEADER_LENGTH);
+
+ ByteBuffer bb = ByteBuffer.wrap(buffer, start, length);
+
+ short version = bb.get();
+ if (!SUPPORTED_VERSIONS.contains(version)) {
+ throw new DeserializationException(VERSION_NOT_SUPPORTED + version);
+ }
+
+ short type = bb.get();
+ int messageLength = bb.getShort();
+
+ if (type == FPM_TYPE_KEEPALIVE) {
+ return new FpmHeader(version, type, messageLength, null);
+ }
+
+ if (type != FPM_TYPE_NETLINK) {
+ throw new DeserializationException(TYPE_NOT_SUPPORTED + type);
+ }
+
+ Netlink netlink = Netlink.decode(buffer, bb.position(), bb.limit() - bb.position());
+
+ return new FpmHeader(version, type, messageLength, netlink);
+ }
+
+ /**
+ * Encode the FpmHeader contents into a ChannelBuffer.
+ *
+ * @return filled in ChannelBuffer
+ */
+ public ChannelBuffer encode() {
+
+ ChannelBuffer cb = ChannelBuffers.buffer(FPM_MESSAGE_MAX_LENGTH);
+
+ cb.writeByte(version);
+ cb.writeByte(type);
+ cb.writeShort(length);
+
+ netlink.encode(cb);
+ return cb;
+ }
+}