Test for SSHD-721. Many concurrent port forward connections deadlock. Project: http://git-wip-us.apache.org/repos/asf/mina-sshd/repo Commit: http://git-wip-us.apache.org/repos/asf/mina-sshd/commit/5abc47e8 Tree: http://git-wip-us.apache.org/repos/asf/mina-sshd/tree/5abc47e8 Diff: http://git-wip-us.apache.org/repos/asf/mina-sshd/diff/5abc47e8
Branch: refs/heads/master Commit: 5abc47e8cc4655c8d58b6d8b41c291c33c2e13db Parents: 83925cb Author: bkuker <bku...@martellotech.com> Authored: Fri Apr 13 16:19:46 2018 -0400 Committer: bkuker <bku...@martellotech.com> Committed: Mon Apr 16 08:20:54 2018 -0400 ---------------------------------------------------------------------- .../forward/ConcurrentConnectionTest.java | 281 +++++++++++++++++++ 1 file changed, 281 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/mina-sshd/blob/5abc47e8/sshd-core/src/test/java/org/apache/sshd/common/forward/ConcurrentConnectionTest.java ---------------------------------------------------------------------- diff --git a/sshd-core/src/test/java/org/apache/sshd/common/forward/ConcurrentConnectionTest.java b/sshd-core/src/test/java/org/apache/sshd/common/forward/ConcurrentConnectionTest.java new file mode 100644 index 0000000..38434df --- /dev/null +++ b/sshd-core/src/test/java/org/apache/sshd/common/forward/ConcurrentConnectionTest.java @@ -0,0 +1,281 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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.apache.sshd.common.forward; + +import java.io.IOException; +import java.net.InetSocketAddress; +import java.net.ServerSocket; +import java.net.Socket; +import java.net.SocketException; +import java.util.concurrent.CyclicBarrier; +import java.util.concurrent.TimeUnit; +import java.util.concurrent.atomic.AtomicInteger; + +import org.apache.sshd.client.SshClient; +import org.apache.sshd.client.session.ClientSession; +import org.apache.sshd.common.session.Session; +import org.apache.sshd.common.util.net.SshdSocketAddress; +import org.apache.sshd.server.SshServer; +import org.apache.sshd.server.forward.AcceptAllForwardingFilter; +import org.apache.sshd.server.forward.ForwardingFilter; +import org.apache.sshd.server.keyprovider.SimpleGeneratorHostKeyProvider; +import org.apache.sshd.util.test.BaseTestSupport; +import org.junit.After; +import org.junit.AfterClass; +import org.junit.Before; +import org.junit.BeforeClass; +import org.junit.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Port forwarding test multiple clients connecting at once. + */ +public class ConcurrentConnectionTest extends BaseTestSupport { + private static final byte[] PAYLOAD_TO_SERVER = "To Server -> To Server -> To Server".getBytes(); + private static final byte[] PAYLOAD_TO_CLIENT = "<- To Client <- To Client <-".getBytes(); + private final static Logger LOG = LoggerFactory.getLogger(ConcurrentConnectionTest.class); + + // These are the critical test parameters. + // When the number of clients is greater than or equal to the number of IO + // Workers, the server deadlocks + private static final int SSHD_NIO_WORKERS = 8; + private static final int PORT_FORWARD_CLIENT_COUNT = 12; + + // For very large numbers of clients and small numbers of threads this may + // need to be increased + private static final int TIMEOUT = (int) TimeUnit.SECONDS.toMillis(10L); + + // Test Server State + private int testServerPort; + private ServerSocket testServerSock; + private Thread testServerThread; + + // SSHD Server State + private static int sshServerPort; + private static SshServer server; + + // SSH Client State + private ClientSession session; + + /* + * Start a server to forward to. + * + * Reads PAYLOAD_TO_SERVER from client and then sends PAYLOAD_TO_CLIENT to + * client. This server emulates a web server, closely enough for thie test + */ + @Before + public void startTestServer() throws Exception { + final AtomicInteger activeServers = new AtomicInteger(0); + testServerThread = new Thread(() -> { + try { + testServerSock = new ServerSocket(0); + testServerPort = testServerSock.getLocalPort(); + LOG.debug("Listening on {}", testServerPort); + while (true) { + final Socket s = testServerSock.accept(); + LOG.debug("Got connection"); + final Thread server = new Thread(() -> { + try { + LOG.debug("Active Servers: {}", activeServers.incrementAndGet()); + final byte[] buf = new byte[PAYLOAD_TO_SERVER.length]; + final long r = s.getInputStream().read(buf); + LOG.debug("Read {} payload from client", r); + s.getOutputStream().write(PAYLOAD_TO_CLIENT); + LOG.debug("Wrote payload to client"); + s.close(); + LOG.debug("Active Servers: {}", activeServers.decrementAndGet()); + } catch (final Throwable t) { + LOG.error("Error", t); + } + }); + server.setDaemon(true); + server.setName("Server " + s.getPort()); + server.start(); + } + } catch (final SocketException e) { + LOG.debug("Shutting down test server"); + } catch (final Throwable t) { + LOG.error("Error", t); + } + }); + testServerThread.setDaemon(true); + testServerThread.setName("Server Acceptor"); + testServerThread.start(); + Thread.sleep(100); + } + + @After + public void stopTestServer() throws Exception { + testServerSock.close(); + testServerThread.interrupt(); + } + + @BeforeClass + public static void startSshServer() throws IOException { + LOG.debug("Starting SSHD..."); + server = SshServer.setUpDefaultServer(); + server.setPasswordAuthenticator((u, p, s) -> true); + server.setForwardingFilter(AcceptAllForwardingFilter.INSTANCE); + server.setKeyPairProvider(new SimpleGeneratorHostKeyProvider()); + server.setNioWorkers(SSHD_NIO_WORKERS); + server.setForwardingFilter(new ForwardingFilter() { + + @Override + public boolean canListen(SshdSocketAddress address, Session session) { + // TODO Auto-generated method stub + return true; + } + + @Override + public boolean canConnect(Type type, SshdSocketAddress address, Session session) { + // TODO Auto-generated method stub + return false; + } + + @Override + public boolean canForwardX11(Session session, String requestType) { + // TODO Auto-generated method stub + return false; + } + + @Override + public boolean canForwardAgent(Session session, String requestType) { + // TODO Auto-generated method stub + return false; + } + }); + server.start(); + sshServerPort = server.getPort(); + LOG.debug("SSHD Running on port {}", server.getPort()); + } + + @AfterClass + public static void stopServer() throws IOException { + if (!server.close(true).await(TIMEOUT)) { + LOG.warn("Failed to close server within {} sec.", TimeUnit.MILLISECONDS.toSeconds(TIMEOUT)); + } + } + + @Before + public void createClient() throws IOException { + final SshClient client = SshClient.setUpDefaultClient(); + client.setForwardingFilter(AcceptAllForwardingFilter.INSTANCE); + client.start(); + LOG.debug("Connecting..."); + session = client.connect("user", TEST_LOCALHOST, sshServerPort).verify(TIMEOUT).getSession(); + LOG.debug("Authenticating..."); + session.addPasswordIdentity("foo"); + session.auth().verify(TIMEOUT); + LOG.debug("Authenticated"); + } + + @After + public void stopClient() throws Exception { + LOG.debug("Disconnecting Client"); + try { + assertTrue("Failed to close session", session.close(true).await(TIMEOUT)); + } finally { + session = null; + } + } + + @Test + /* + * Run PORT_FORWARD_CLIENT_COUNT simultaneous server threads. + * + * Emulates a web browser making a number of simultaneous requests on + * different connections to the same server HTTP specifies no more than two, + * but most modern browsers do 6 or more. + */ + public void testConcurrentConnectionsToPortForward() throws Exception { + final SshdSocketAddress remote = new SshdSocketAddress(TEST_LOCALHOST, 0); + final SshdSocketAddress local = new SshdSocketAddress(TEST_LOCALHOST, testServerPort); + final SshdSocketAddress bound = session.startRemotePortForwarding(remote, local); + final int forwardedPort = bound.getPort(); + + final CyclicBarrier b = new CyclicBarrier(PORT_FORWARD_CLIENT_COUNT, () -> { + LOG.debug("And away we go."); + }); + + final AtomicInteger success = new AtomicInteger(0); + final AtomicInteger fail = new AtomicInteger(0); + final long[] bytesRead = new long[PORT_FORWARD_CLIENT_COUNT]; + + for (int i = 0; i < PORT_FORWARD_CLIENT_COUNT; i++) { + final long wait = 100 * i; + final int n = i; + final Thread t = new Thread(() -> { + try { + bytesRead[n] = makeClientRequest(forwardedPort, b, wait); + LOG.debug("Complete, received full payload from server."); + success.incrementAndGet(); + } catch (final Exception e) { + fail.incrementAndGet(); + LOG.error("Error in client code", e); + } + }); + t.setName("Client " + i); + t.setDaemon(true); + t.start(); + } + + while (true) { + if (success.get() + fail.get() == PORT_FORWARD_CLIENT_COUNT) { + break; + } + Thread.sleep(100); + } + + for (int i = 0; i < PORT_FORWARD_CLIENT_COUNT; i++) { + assertEquals("Mismatched data length read from server for client " + i, PAYLOAD_TO_CLIENT.length, + bytesRead[i]); + } + + assertEquals("Not all clients succeeded", PORT_FORWARD_CLIENT_COUNT, success.get()); + } + + /** + * Send PAYLOAD_TO_SERVER to the server, then read PAYLOAD_TO_CLIENT from + * server. Emulates a web browser making a request + */ + private long makeClientRequest(final int serverPort, final CyclicBarrier barrier, final long wait) + throws Exception { + outputDebugMessage("readInLoop(port=%d)", serverPort); + + final Socket s = new Socket(); + s.setSoTimeout(TIMEOUT); + + barrier.await(); + + s.connect(new InetSocketAddress(TEST_LOCALHOST, serverPort)); + + s.getOutputStream().write(PAYLOAD_TO_SERVER); + + final byte[] buf = new byte[PAYLOAD_TO_CLIENT.length]; + final long r = s.getInputStream().read(buf); + LOG.debug("Read {} payload from server", r); + + assertEquals("Mismatched data length", PAYLOAD_TO_CLIENT.length, r); + s.close(); + + return r; + } + +} \ No newline at end of file
