* 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.netconf.nettyutil.handler.ssh.client;
-import com.google.common.base.Preconditions;
-import io.netty.buffer.ByteBuf;
+import static com.google.common.base.Verify.verify;
+import static java.util.Objects.requireNonNull;
+
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;
import io.netty.util.concurrent.Future;
-import io.netty.util.concurrent.GenericFutureListener;
+import io.netty.util.concurrent.FutureListener;
import java.io.IOException;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.VarHandle;
import java.net.SocketAddress;
-import org.apache.sshd.client.SshClient;
-import org.apache.sshd.client.channel.ClientChannel;
-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.client.session.ClientSession;
-import org.apache.sshd.client.session.ClientSessionCreator;
-import org.apache.sshd.common.future.CloseFuture;
-import org.apache.sshd.common.future.SshFutureListener;
+import java.util.concurrent.TimeUnit;
+import org.checkerframework.checker.lock.qual.GuardedBy;
+import org.checkerframework.checker.lock.qual.Holding;
+import org.eclipse.jdt.annotation.Nullable;
import org.opendaylight.netconf.nettyutil.handler.ssh.authentication.AuthenticationHandler;
+import org.opendaylight.netconf.shaded.sshd.client.channel.ClientChannel;
+import org.opendaylight.netconf.shaded.sshd.client.future.AuthFuture;
+import org.opendaylight.netconf.shaded.sshd.client.future.ConnectFuture;
+import org.opendaylight.netconf.shaded.sshd.client.future.OpenFuture;
+import org.opendaylight.netconf.shaded.sshd.client.session.ClientSession;
+import org.opendaylight.netconf.shaded.sshd.core.CoreModuleProperties;
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 {
+public final class AsyncSshHandler extends ChannelOutboundHandlerAdapter {
private static final Logger LOG = LoggerFactory.getLogger(AsyncSshHandler.class);
+ private static final VarHandle DISCONNECTED;
+
+ static {
+ try {
+ DISCONNECTED = MethodHandles.lookup().findVarHandle(AsyncSshHandler.class, "disconnected", boolean.class);
+ } catch (NoSuchFieldException | IllegalAccessException e) {
+ throw new ExceptionInInitializerError(e);
+ }
+ }
public static final String SUBSYSTEM = "netconf";
public static final int SSH_DEFAULT_NIO_WORKERS = 8;
- // Disable default timeouts from mina sshd
- private static final long DEFAULT_TIMEOUT = -1L;
- public static final SshClient DEFAULT_CLIENT;
+ public static final NetconfSshClient DEFAULT_CLIENT;
+
static {
- final SshClient c = SshClient.setUpDefaultClient();
- c.getProperties().put(SshClient.AUTH_TIMEOUT, Long.toString(DEFAULT_TIMEOUT));
- c.getProperties().put(SshClient.IDLE_TIMEOUT, Long.toString(DEFAULT_TIMEOUT));
+ final NetconfSshClient c = new NetconfClientBuilder().build();
+ // Disable default timeouts from mina sshd
+ c.getProperties().put(CoreModuleProperties.AUTH_TIMEOUT.getName(), "0");
+ c.getProperties().put(CoreModuleProperties.IDLE_TIMEOUT.getName(), "0");
+ c.getProperties().put(CoreModuleProperties.NIO2_READ_TIMEOUT.getName(), "0");
+ c.getProperties().put(CoreModuleProperties.TCP_NODELAY.getName(), true);
+
// TODO make configurable, or somehow reuse netty threadpool
c.setNioWorkers(SSH_DEFAULT_NIO_WORKERS);
c.start();
}
private final AuthenticationHandler authenticationHandler;
- private final ClientSessionCreator sshClient;
- private Future<?> negotiationFuture;
+ private final Future<?> negotiationFuture;
+ private final NetconfSshClient sshClient;
- private AsyncSshHandlerReader sshReadAsyncListener;
- private AsyncSshHandlerWriter sshWriteAsyncHandler;
+ // Initialized by connect()
+ @GuardedBy("this")
+ private ChannelPromise connectPromise;
- private ClientChannel channel;
+ private AsyncSshHandlerWriter sshWriteAsyncHandler;
+ private NettyAwareChannelSubsystem channel;
private ClientSession session;
- private ChannelPromise connectPromise;
- private GenericFutureListener negotiationFutureListener;
+ private FutureListener<Object> negotiationFutureListener;
+
+ private volatile boolean disconnected;
- public AsyncSshHandler(final AuthenticationHandler authenticationHandler, final ClientSessionCreator sshClient,
+ public AsyncSshHandler(final AuthenticationHandler authenticationHandler, final NetconfSshClient sshClient,
final Future<?> negotiationFuture) {
- this(authenticationHandler, sshClient);
+ this.authenticationHandler = requireNonNull(authenticationHandler);
+ this.sshClient = requireNonNull(sshClient);
this.negotiationFuture = negotiationFuture;
}
/**
+ * Constructor of {@code AsyncSshHandler}.
*
- * @param authenticationHandler
- * @param sshClient started SshClient
+ * @param authenticationHandler authentication handler
+ * @param sshClient started SshClient
*/
- public AsyncSshHandler(final AuthenticationHandler authenticationHandler, final ClientSessionCreator sshClient) {
- this.authenticationHandler = Preconditions.checkNotNull(authenticationHandler);
- this.sshClient = Preconditions.checkNotNull(sshClient);
+ public AsyncSshHandler(final AuthenticationHandler authenticationHandler, final NetconfSshClient sshClient) {
+ this(authenticationHandler, sshClient, null);
}
public static AsyncSshHandler createForNetconfSubsystem(final AuthenticationHandler authenticationHandler) {
}
/**
- *
* Create AsyncSshHandler for netconf subsystem. Negotiation future has to be set to success after successful
- * NETCONF negotiation.
+ * netconf negotiation.
*
- * @param authenticationHandler
- * @param negotiationFuture
- * @return
+ * @param authenticationHandler authentication handler
+ * @param negotiationFuture negotiation future
+ * @return {@code AsyncSshHandler}
*/
public static AsyncSshHandler createForNetconfSubsystem(final AuthenticationHandler authenticationHandler,
- final Future<?> negotiationFuture) {
- return new AsyncSshHandler(authenticationHandler, DEFAULT_CLIENT, negotiationFuture);
+ final Future<?> negotiationFuture, final @Nullable NetconfSshClient sshClient) {
+ return new AsyncSshHandler(authenticationHandler, sshClient != null ? sshClient : DEFAULT_CLIENT,
+ negotiationFuture);
}
- private void startSsh(final ChannelHandlerContext ctx, final SocketAddress address) throws IOException {
- LOG.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());
- }
- }
- });
+ @Override
+ public synchronized void write(final ChannelHandlerContext ctx, final Object msg, final ChannelPromise promise) {
+ sshWriteAsyncHandler.write(ctx, msg, promise);
}
- private synchronized void handleSshSessionCreated(final ConnectFuture future, final ChannelHandlerContext ctx) {
- try {
- LOG.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 {
- // Exception does not have to be set in the future, add simple exception in such case
- final Throwable exception = future.getException() == null ?
- new IllegalStateException("Authentication failed") :
- future.getException();
- handleSshSetupFailure(ctx, exception);
- }
+ @Override
+ public synchronized void connect(final ChannelHandlerContext ctx, final SocketAddress remoteAddress,
+ final SocketAddress localAddress, final ChannelPromise promise) throws IOException {
+ LOG.debug("SSH session connecting on channel {}. promise: {}", ctx.channel(), promise);
+ connectPromise = requireNonNull(promise);
+
+ if (negotiationFuture != null) {
+ negotiationFutureListener = future -> {
+ if (future.isSuccess()) {
+ promise.setSuccess();
}
- });
- } catch (final IOException e) {
- handleSshSetupFailure(ctx, e);
+ };
+ //complete connection promise with netconf negotiation future
+ negotiationFuture.addListener(negotiationFutureListener);
}
+
+ LOG.debug("Starting SSH to {} on channel: {}", remoteAddress, ctx.channel());
+ sshClient.connect(authenticationHandler.getUsername(), remoteAddress)
+ // FIXME: this is a blocking call, we should handle this with a concurrently-scheduled timeout. We do not
+ // have a Timer ready, so perhaps we should be using the event loop?
+ .verify(ctx.channel().config().getConnectTimeoutMillis(), TimeUnit.MILLISECONDS)
+ .addListener(future -> onConnectComplete(future, ctx));
}
- private synchronized void handleSshAuthenticated(final ClientSession session, final ChannelHandlerContext ctx) {
+ private synchronized void onConnectComplete(final ConnectFuture connectFuture, final ChannelHandlerContext ctx) {
+ final var cause = connectFuture.getException();
+ if (cause != null) {
+ onOpenFailure(ctx, cause);
+ return;
+ }
+
+ final var clientSession = connectFuture.getSession();
+ LOG.trace("SSH session {} created on channel: {}", clientSession, ctx.channel());
+ verify(clientSession instanceof NettyAwareClientSession, "Unexpected session %s", clientSession);
+
+ final var localSession = (NettyAwareClientSession) clientSession;
+ session = localSession;
+
+ final AuthFuture authFuture;
try {
- LOG.debug("SSH session authenticated on channel: {}, server version: {}", ctx.channel(), session.getServerVersion());
+ authFuture = authenticationHandler.authenticate(localSession);
+ } catch (final IOException e) {
+ onOpenFailure(ctx, e);
+ return;
+ }
- 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());
- }
- }
- });
+ authFuture.addListener(future -> onAuthComplete(future, localSession, ctx));
+ }
+ private synchronized void onAuthComplete(final AuthFuture authFuture, final NettyAwareClientSession clientSession,
+ final ChannelHandlerContext ctx) {
+ final var cause = authFuture.getException();
+ if (cause != null) {
+ onOpenFailure(ctx, new AuthenticationFailedException("Authentication failed", cause));
+ return;
+ }
+ if (disconnected) {
+ LOG.debug("Skipping SSH subsystem allocation, channel: {}", ctx.channel());
+ return;
+ }
+
+ LOG.debug("SSH session authenticated on channel: {}, server version: {}", ctx.channel(),
+ clientSession.getServerVersion());
+ final OpenFuture openFuture;
+ try {
+ channel = clientSession.createSubsystemChannel(SUBSYSTEM, ctx);
+ channel.setStreaming(ClientChannel.Streaming.Async);
+ openFuture = channel.open();
} catch (final IOException e) {
- handleSshSetupFailure(ctx, e);
+ onOpenFailure(ctx, e);
+ return;
}
+
+ openFuture.addListener(future -> ctx.executor().execute(() -> onOpenComplete(future, ctx)));
}
- private synchronized void handleSshChanelOpened(final ChannelHandlerContext ctx) {
- LOG.trace("SSH subsystem channel opened successfully on channel: {}", ctx.channel());
+ // This callback has to run on the channel's executor because it runs fireChannelActive(), which needs to be
+ // delivered synchronously. If we were to execute on some other thread we would end up delaying the event,
+ // potentially creating havoc in the pipeline.
+ private synchronized void onOpenComplete(final OpenFuture openFuture, final ChannelHandlerContext ctx) {
+ final var cause = openFuture.getException();
+ if (cause != null) {
+ onOpenFailure(ctx, cause);
+ return;
+ }
+ if (disconnected) {
+ LOG.trace("Skipping activation, channel: {}", ctx.channel());
+ return;
+ }
- if(negotiationFuture == null) {
+ LOG.trace("SSH subsystem channel opened successfully on channel: {}", ctx.channel());
+ if (negotiationFuture == null) {
connectPromise.setSuccess();
}
- // TODO we should also read from error stream and at least log from that
-
- sshReadAsyncListener = new AsyncSshHandlerReader(new AutoCloseable() {
- @Override
- public void close() throws Exception {
- AsyncSshHandler.this.disconnect(ctx, ctx.newPromise());
- }
- }, new AsyncSshHandlerReader.ReadMsgHandler() {
- @Override
- public void onMessageRead(final ByteBuf msg) {
- ctx.fireChannelRead(msg);
- }
- }, channel.toString(), channel.getAsyncOut());
-
- // if readAsyncListener receives immediate close, it will close this handler and closing this handler sets channel variable to null
- if(channel != null) {
- sshWriteAsyncHandler = new AsyncSshHandlerWriter(channel.getAsyncIn());
- ctx.fireChannelActive();
- }
+ sshWriteAsyncHandler = new AsyncSshHandlerWriter(channel.getAsyncIn());
+ ctx.fireChannelActive();
+ channel.onClose(() -> disconnect(ctx, ctx.newPromise()));
}
- private synchronized void handleSshSetupFailure(final ChannelHandlerContext ctx, final Throwable e) {
- LOG.warn("Unable to setup SSH connection on channel: {}", ctx.channel(), e);
+ @Holding("this")
+ private void onOpenFailure(final ChannelHandlerContext ctx, final Throwable cause) {
+ LOG.warn("Unable to setup SSH connection on channel: {}", ctx.channel(), cause);
// If the promise is not yet done, we have failed with initial connect and set connectPromise to failure
- if(!connectPromise.isDone()) {
- connectPromise.setFailure(e);
+ if (!connectPromise.isDone()) {
+ connectPromise.setFailure(cause);
}
disconnect(ctx, ctx.newPromise());
}
@Override
- public synchronized void write(final ChannelHandlerContext ctx, final Object msg, final ChannelPromise promise) {
- sshWriteAsyncHandler.write(ctx, msg, promise);
+ public void close(final ChannelHandlerContext ctx, final ChannelPromise promise) {
+ disconnect(ctx, promise);
}
@Override
- public synchronized void connect(final ChannelHandlerContext ctx, final SocketAddress remoteAddress, final SocketAddress localAddress, final ChannelPromise promise) throws Exception {
- LOG.debug("SSH session connecting on channel {}. promise: {} ", ctx.channel(), connectPromise);
- this.connectPromise = promise;
-
- if(negotiationFuture != null) {
-
- negotiationFutureListener = new GenericFutureListener<Future<?>>() {
- @Override
- public void operationComplete(final Future<?> future) {
- if (future.isSuccess()) {
- connectPromise.setSuccess();
- }
- }
- };
- //complete connection promise with netconf negotiation future
- negotiationFuture.addListener(negotiationFutureListener);
+ public void disconnect(final ChannelHandlerContext ctx, final ChannelPromise promise) {
+ if (DISCONNECTED.compareAndSet(this, false, true)) {
+ ctx.executor().execute(() -> safelyDisconnect(ctx, 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) {
- LOG.trace("Closing SSH session on channel: {} with connect promise in state: {}", ctx.channel(), connectPromise);
-
- // If we have already succeeded and the session was dropped after, we need to fire inactive to notify reconnect logic
- if(connectPromise.isSuccess()) {
+ // This method has the potential to interact with the channel pipeline, for example via fireChannelInactive(). These
+ // callbacks need to complete during execution of this method and therefore this method needs to be executing on
+ // the channel's executor.
+ @SuppressWarnings("checkstyle:IllegalCatch")
+ private synchronized void safelyDisconnect(final ChannelHandlerContext ctx, final ChannelPromise promise) {
+ LOG.trace("Closing SSH session on channel: {} with connect promise in state: {}", ctx.channel(),
+ connectPromise);
+
+ // If we have already succeeded and the session was dropped after,
+ // we need to fire inactive to notify reconnect logic
+ if (connectPromise.isSuccess()) {
ctx.fireChannelInactive();
}
- if(sshWriteAsyncHandler != null) {
+ if (sshWriteAsyncHandler != null) {
sshWriteAsyncHandler.close();
}
- if(sshReadAsyncListener != null) {
- sshReadAsyncListener.close();
- }
-
//If connection promise is not already set, it means negotiation failed
//we must set connection promise to failure
- if(!connectPromise.isDone()) {
+ if (!connectPromise.isDone()) {
connectPromise.setFailure(new IllegalStateException("Negotiation failed"));
}
//Remove listener from negotiation future, we don't want notifications
//from negotiation anymore
- if(negotiationFuture != null) {
+ if (negotiationFuture != null) {
negotiationFuture.removeListener(negotiationFutureListener);
}
- if(session!= null && !session.isClosed() && !session.isClosing()) {
- session.close(false).addListener(new SshFutureListener<CloseFuture>() {
- @Override
- public void operationComplete(final CloseFuture future) {
- if (future.isClosed() == false) {
+ if (session != null && !session.isClosed() && !session.isClosing()) {
+ session.close(false).addListener(future -> {
+ synchronized (this) {
+ if (!future.isClosed()) {
session.close(true);
}
session = null;
});
}
- // Super disconnect is necessary in this case since we are using NioSocketChannel and it needs to cleanup its resources
- // e.g. Socket that it tries to open in its constructor (https://bugs.opendaylight.org/show_bug.cgi?id=2430)
- // TODO better solution would be to implement custom ChannelFactory + Channel that will use mina SSH lib internally: port this to custom channel implementation
+ // Super disconnect is necessary in this case since we are using NioSocketChannel and it needs
+ // to cleanup its resources e.g. Socket that it tries to open in its constructor
+ // (https://bugs.opendaylight.org/show_bug.cgi?id=2430)
+ // TODO better solution would be to implement custom ChannelFactory + Channel
+ // that will use mina SSH lib internally: port this to custom channel implementation
try {
// Disconnect has to be closed after inactive channel event was fired, because it interferes with it
super.disconnect(ctx, ctx.newPromise());
LOG.warn("Unable to cleanup all resources for channel: {}. Ignoring.", ctx.channel(), e);
}
- channel = null;
+ if (channel != null) {
+ //TODO: see if calling just close() is sufficient
+ //channel.close(false);
+ channel.close();
+ channel = null;
+ }
promise.setSuccess();
LOG.debug("SSH session closed on channel: {}", ctx.channel());
}
-
}