--- /dev/null
+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.opendaylight.controller.netconf.nettyutil.handler.ssh.client;
+
+import com.google.common.base.Preconditions;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelOutboundHandlerAdapter;
+import io.netty.channel.ChannelPromise;
+import java.io.IOException;
+import java.net.SocketAddress;
+import org.apache.sshd.ClientChannel;
+import org.apache.sshd.ClientSession;
+import org.apache.sshd.SshClient;
+import org.apache.sshd.client.future.AuthFuture;
+import org.apache.sshd.client.future.ConnectFuture;
+import org.apache.sshd.client.future.OpenFuture;
+import org.apache.sshd.common.future.CloseFuture;
+import org.apache.sshd.common.future.SshFutureListener;
+import org.apache.sshd.common.io.IoInputStream;
+import org.apache.sshd.common.io.IoReadFuture;
+import org.apache.sshd.common.util.Buffer;
+import org.opendaylight.controller.netconf.nettyutil.handler.ssh.authentication.AuthenticationHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Netty SSH handler class. Acts as interface between Netty and SSH library.
+ */
+public class AsyncSshHandler extends ChannelOutboundHandlerAdapter {
+
+ private static final Logger logger = LoggerFactory.getLogger(AsyncSshHandler.class);
+ public static final String SUBSYSTEM = "netconf";
+
+ public static final SshClient DEFAULT_CLIENT = SshClient.setUpDefaultClient();
+
+ public static final int SSH_DEFAULT_NIO_WORKERS = 8;
+
+ static {
+ // TODO make configurable, or somehow reuse netty threadpool
+ DEFAULT_CLIENT.setNioWorkers(SSH_DEFAULT_NIO_WORKERS);
+ DEFAULT_CLIENT.start();
+ }
+
+ private final AuthenticationHandler authenticationHandler;
+ private final SshClient sshClient;
+
+ private SshReadAsyncListener sshReadAsyncListener;
+ private ClientChannel channel;
+ private ClientSession session;
+ private ChannelPromise connectPromise;
+
+ public static AsyncSshHandler createForNetconfSubsystem(final AuthenticationHandler authenticationHandler) throws IOException {
+ return new AsyncSshHandler(authenticationHandler, DEFAULT_CLIENT);
+ }
+
+ /**
+ *
+ * @param authenticationHandler
+ * @param sshClient started SshClient
+ * @throws IOException
+ */
+ public AsyncSshHandler(final AuthenticationHandler authenticationHandler, final SshClient sshClient) throws IOException {
+ this.authenticationHandler = Preconditions.checkNotNull(authenticationHandler);
+ this.sshClient = Preconditions.checkNotNull(sshClient);
+ // Start just in case
+ sshClient.start();
+ }
+
+ private void startSsh(final ChannelHandlerContext ctx, final SocketAddress address) {
+ logger.debug("Starting SSH to {} on channel: {}", address, ctx.channel());
+
+ final ConnectFuture sshConnectionFuture = sshClient.connect(authenticationHandler.getUsername(), address);
+ sshConnectionFuture.addListener(new SshFutureListener<ConnectFuture>() {
+ @Override
+ public void operationComplete(final ConnectFuture future) {
+ if (future.isConnected()) {
+ handleSshSessionCreated(future, ctx);
+ } else {
+ handleSshSetupFailure(ctx, future.getException());
+ }
+ }
+ });
+ }
+
+ private synchronized void handleSshSessionCreated(final ConnectFuture future, final ChannelHandlerContext ctx) {
+ try {
+ logger.trace("SSH session created on channel: {}", ctx.channel());
+
+ session = future.getSession();
+ final AuthFuture authenticateFuture = authenticationHandler.authenticate(session);
+ authenticateFuture.addListener(new SshFutureListener<AuthFuture>() {
+ @Override
+ public void operationComplete(final AuthFuture future) {
+ if (future.isSuccess()) {
+ handleSshAuthenticated(session, ctx);
+ } else {
+ handleSshSetupFailure(ctx, future.getException());
+ }
+ }
+ });
+ } catch (final IOException e) {
+ handleSshSetupFailure(ctx, e);
+ }
+ }
+
+ private synchronized void handleSshAuthenticated(final ClientSession session, final ChannelHandlerContext ctx) {
+ try {
+ logger.debug("SSH session authenticated on channel: {}, server version: {}", ctx.channel(), session.getServerVersion());
+
+ channel = session.createSubsystemChannel(SUBSYSTEM);
+ channel.setStreaming(ClientChannel.Streaming.Async);
+ channel.open().addListener(new SshFutureListener<OpenFuture>() {
+ @Override
+ public void operationComplete(final OpenFuture future) {
+ if(future.isOpened()) {
+ handleSshChanelOpened(ctx);
+ } else {
+ handleSshSetupFailure(ctx, future.getException());
+ }
+ }
+ });
+
+
+ } catch (final IOException e) {
+ handleSshSetupFailure(ctx, e);
+ }
+ }
+
+ private synchronized void handleSshChanelOpened(final ChannelHandlerContext ctx) {
+ logger.trace("SSH subsystem channel opened successfully on channel: {}", ctx.channel());
+
+ connectPromise.setSuccess();
+ connectPromise = null;
+ ctx.fireChannelActive();
+
+ final IoInputStream asyncOut = channel.getAsyncOut();
+ sshReadAsyncListener = new SshReadAsyncListener(ctx, asyncOut);
+ }
+
+ private synchronized void handleSshSetupFailure(final ChannelHandlerContext ctx, final Throwable e) {
+ logger.warn("Unable to setup SSH connection on channel: {}", ctx.channel(), e);
+ connectPromise.setFailure(e);
+ connectPromise = null;
+ throw new IllegalStateException("Unable to setup SSH connection on channel: " + ctx.channel(), e);
+ }
+
+ @Override
+ public synchronized void write(final ChannelHandlerContext ctx, final Object msg, final ChannelPromise promise) {
+ try {
+ if(channel.getAsyncIn().isClosed() || channel.getAsyncIn().isClosing()) {
+ handleSshSessionClosed(ctx);
+ } else {
+ channel.getAsyncIn().write(toBuffer(msg));
+ ((ByteBuf) msg).release();
+ }
+ } catch (final Exception e) {
+ logger.warn("Exception while writing to SSH remote on channel {}", ctx.channel(), e);
+ throw new IllegalStateException("Exception while writing to SSH remote on channel " + ctx.channel(),e);
+ }
+ }
+
+ private static void handleSshSessionClosed(final ChannelHandlerContext ctx) {
+ logger.debug("SSH session closed on channel: {}", ctx.channel());
+ ctx.fireChannelInactive();
+ }
+
+ private Buffer toBuffer(final Object msg) {
+ // TODO Buffer vs ByteBuf translate, Can we handle that better ?
+ Preconditions.checkState(msg instanceof ByteBuf);
+ final ByteBuf byteBuf = (ByteBuf) msg;
+ final byte[] temp = new byte[byteBuf.readableBytes()];
+ byteBuf.readBytes(temp, 0, byteBuf.readableBytes());
+ return new Buffer(temp);
+ }
+
+ @Override
+ public synchronized void connect(final ChannelHandlerContext ctx, final SocketAddress remoteAddress, final SocketAddress localAddress, final ChannelPromise promise) throws Exception {
+ this.connectPromise = promise;
+ startSsh(ctx, remoteAddress);
+ }
+
+ @Override
+ public void close(final ChannelHandlerContext ctx, final ChannelPromise promise) throws Exception {
+ disconnect(ctx, promise);
+ }
+
+ @Override
+ public synchronized void disconnect(final ChannelHandlerContext ctx, final ChannelPromise promise) throws Exception {
+ if(sshReadAsyncListener != null) {
+ sshReadAsyncListener.close();
+ }
+
+ session.close(false).addListener(new SshFutureListener<CloseFuture>() {
+ @Override
+ public void operationComplete(final CloseFuture future) {
+ if(future.isClosed() == false) {
+ session.close(true);
+ }
+ session = null;
+ }
+ });
+
+ channel = null;
+ }
+
+ /**
+ * Listener over async input stream from SSH session.
+ * This listeners schedules reads in a loop until the session is closed or read fails.
+ */
+ private static class SshReadAsyncListener implements SshFutureListener<IoReadFuture>, AutoCloseable {
+ private static final int BUFFER_SIZE = 8192;
+
+ private final ChannelHandlerContext ctx;
+
+ private IoInputStream asyncOut;
+ private Buffer buf;
+ private IoReadFuture currentReadFuture;
+
+ public SshReadAsyncListener(final ChannelHandlerContext ctx, final IoInputStream asyncOut) {
+ this.ctx = ctx;
+ this.asyncOut = asyncOut;
+ buf = new Buffer(BUFFER_SIZE);
+ asyncOut.read(buf).addListener(this);
+ }
+
+ @Override
+ public synchronized void operationComplete(final IoReadFuture future) {
+ if(future.getException() != null) {
+
+ if(asyncOut.isClosed() || asyncOut.isClosing()) {
+ // We are closing
+ handleSshSessionClosed(ctx);
+ } else {
+ logger.warn("Exception while reading from SSH remote on channel {}", ctx.channel(), future.getException());
+ throw new IllegalStateException("Exception while reading from SSH remote on channel " + ctx.channel(), future.getException());
+ }
+ }
+
+ if (future.getRead() > 0) {
+ ctx.fireChannelRead(Unpooled.wrappedBuffer(buf.array(), 0, future.getRead()));
+
+ // Schedule next read
+ buf = new Buffer(BUFFER_SIZE);
+ currentReadFuture = asyncOut.read(buf);
+ currentReadFuture.addListener(this);
+ }
+ }
+
+ @Override
+ public synchronized void close() throws Exception {
+ // Remove self as listener on close to prevent reading from closed input
+ if(currentReadFuture != null) {
+ currentReadFuture.removeListener(this);
+ }
+
+ asyncOut = null;
+ }
+ }
+}
Code Review / controller.git / commitdiff