Add workaround for SSH connection issue related to SSHD-1028

[netconf.git] / netconf / netconf-netty-util / src / main / java / org / opendaylight / netconf / nettyutil / handler / ssh / sshd1028 / NetconfNio2Session.java

diff --git a/netconf/netconf-netty-util/src/main/java/org/opendaylight/netconf/nettyutil/handler/ssh/sshd1028/NetconfNio2Session.java b/netconf/netconf-netty-util/src/main/java/org/opendaylight/netconf/nettyutil/handler/ssh/sshd1028/NetconfNio2Session.java
new file mode 100644 (file)
index 0000000..9c6e8cf
--- /dev/null
+++ b/netconf/netconf-netty-util/src/main/java/org/opendaylight/netconf/nettyutil/handler/ssh/sshd1028/NetconfNio2Session.java
@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2020 PANTHEON.tech, s.r.o. 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.netconf.nettyutil.handler.ssh.sshd1028;
+
+import java.io.IOException;
+import java.net.SocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.AsynchronousSocketChannel;
+import org.opendaylight.netconf.shaded.sshd.common.FactoryManager;
+import org.opendaylight.netconf.shaded.sshd.common.io.IoHandler;
+import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2CompletionHandler;
+import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2Service;
+import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2Session;
+import org.opendaylight.netconf.shaded.sshd.common.util.Readable;
+
+/**
+ * Custom Nio2Session which fixes the issue with connections not being properly closed.
+ * Should be removed when SSHD-1028 is fixed.
+ */
+public class NetconfNio2Session extends Nio2Session {
+
+    public NetconfNio2Session(final Nio2Service service, final FactoryManager manager, final IoHandler handler,
+                              final AsynchronousSocketChannel socket, final SocketAddress acceptanceAddress)
+        throws IOException {
+        super(service, manager, handler, socket, acceptanceAddress);
+    }
+
+    /**
+     * This method in sshd-osgi:2.5.0 and 2.5.1 contains a bug. The close(true) statement was removed. We can override
+     * it making a workaround for this issue - until SSHD-1028 is fixed.
+     */
+    @Override
+    @SuppressWarnings("IllegalCatch")
+    protected void handleReadCycleCompletion(final ByteBuffer buffer, final Readable bufReader,
+                                             final Nio2CompletionHandler<Integer, Object> completionHandler,
+                                             final Integer result, final Object attachment) {
+        try {
+            boolean debugEnabled = log.isDebugEnabled();
+            if (result >= 0) {
+                if (debugEnabled) {
+                    log.debug("handleReadCycleCompletion({}) read {} bytes", this, result);
+                }
+                buffer.flip();
+                IoHandler handler = getIoHandler();
+                handler.messageReceived(this, bufReader);
+                if (!closeFuture.isClosed()) {
+                    // re-use reference for next iteration since we finished processing it
+                    buffer.clear();
+                    doReadCycle(buffer, completionHandler);
+                } else {
+                    if (debugEnabled) {
+                        log.debug("handleReadCycleCompletion({}) IoSession has been closed, stop reading", this);
+                    }
+                }
+            } else {
+                if (debugEnabled) {
+                    log.debug("handleReadCycleCompletion({}) Socket has been disconnected (result={}), closing "
+                        + "IoSession now", this, result);
+                }
+                close(true);
+            }
+        } catch (Throwable exc) {
+            completionHandler.failed(exc, attachment);
+        }
+    }
+}