SSL/TLS support for OVSDB Southbound API

Change-Id: Ib76653131bdf4b934a484eb72f91af60ff5861c0
Wiki Link : https://wiki.onosproject.org/pages/viewpage.action?pageId=23333242
diff --git a/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/OvsdbChannelInitializer.java b/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/OvsdbChannelInitializer.java
new file mode 100644
index 0000000..5badebf
--- /dev/null
+++ b/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/OvsdbChannelInitializer.java
@@ -0,0 +1,82 @@
+/*
+ * Copyright 2018-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.ovsdb.controller.impl;
+
+import io.netty.channel.ChannelInitializer;
+import io.netty.channel.ChannelPipeline;
+import io.netty.channel.socket.SocketChannel;
+import io.netty.handler.codec.string.StringEncoder;
+import io.netty.handler.ssl.SslHandler;
+import io.netty.handler.timeout.IdleStateHandler;
+import io.netty.handler.timeout.ReadTimeoutHandler;
+import io.netty.util.CharsetUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.net.ssl.SSLContext;
+import javax.net.ssl.SSLEngine;
+
+/**
+ * Creates a ChannelInitializer for a server-side OVSDB channel.
+ */
+public class OvsdbChannelInitializer
+        extends ChannelInitializer<SocketChannel> {
+
+    private final Logger log = LoggerFactory.getLogger(getClass());
+
+    private final SSLContext sslContext;
+    protected Controller controller;
+
+    private static final int READER_IDLE_TIME = 20;
+    private static final int WRITER_IDLE_TIME = 25;
+    private static final int ALL_IDLE_TIME = 0;
+    private static final int TIMEOUT = 180;
+
+    public OvsdbChannelInitializer(Controller controller, SSLContext sslContext) {
+        super();
+        this.controller = controller;
+        this.sslContext = sslContext;
+    }
+
+    @Override
+    protected void initChannel(SocketChannel channel) throws Exception {
+
+        ChannelPipeline pipeline = channel.pipeline();
+        if (sslContext != null) {
+            log.info("OVSDB SSL enabled.");
+            SSLEngine sslEngine = sslContext.createSSLEngine();
+
+            sslEngine.setNeedClientAuth(true);
+            sslEngine.setUseClientMode(false);
+            sslEngine.setEnabledProtocols(sslEngine.getSupportedProtocols());
+            sslEngine.setEnabledCipherSuites(sslEngine.getSupportedCipherSuites());
+            sslEngine.setEnableSessionCreation(true);
+
+            SslHandler sslHandler = new SslHandler(sslEngine);
+            pipeline.addLast("ssl", sslHandler);
+        } else {
+            log.info("OVSDB SSL disabled.");
+        }
+        pipeline.addLast(new StringEncoder(CharsetUtil.UTF_8));
+        pipeline.addLast(new MessageDecoder());
+
+        pipeline.addLast(new IdleStateHandler(READER_IDLE_TIME, WRITER_IDLE_TIME, ALL_IDLE_TIME));
+        pipeline.addLast(new ReadTimeoutHandler(TIMEOUT));
+        controller.handleNewNodeConnection(channel);
+    }
+}
+