7539: JDP Tests failing in VPN environments

Reviewed-by: clanger, hirt

build.sh

@@ -11,6 +11,7 @@ fi
 JETTY_PID=""
 BASEDIR=""
 JMC_DIR=""
+JVM_ARGUMENTS=""
 
 function err_report() {
     err_log "$(date +%T) ${PROGNAME}: Error on line $1"
@@ -86,6 +87,7 @@ function printHelp() {
         printf " \t%s\t%s\n" "--installCore" "to install JMC core"
         printf " \t%s\t%s\n" "--packageJmc" "to package JMC"
         printf " \t%s\t%s\n" "--packageAgent" "to package Agent"
+        printf " \t%s\t%s\n" "--skipJDPMulticastTests" "skip multicast related tests"
         printf " \t%s\t%s\n" "--clean" "to run maven clean"
         printf " \t%s\t%s\n" "--run" "to run JMC, once it is packaged"
         printf " \t%s\t%s\n" "--runAgentExample" "to run Agent 'InstrumentMe' example, once it is packaged"
@@ -103,15 +105,15 @@ function runTests() {
     local timestamp=$1
     startJetty $timestamp
     echo "${timestamp} running tests"
-    mvn verify
+    mvn ${JVM_ARGUMENTS} verify
 }
 
 function runUiTests() {
     local timestamp=$1
     startJetty $timestamp
     installCore $timestamp
     echo "$(date +%T) running UI tests"
-    mvn verify -P uitests
+    mvn ${JVM_ARGUMENTS} verify -P uitests
 }
 
 function packageJmc() {
@@ -121,7 +123,7 @@ function packageJmc() {
     local packageLog="${BASEDIR}/build_${timestamp}.4.package.log"
 
     echo "$(date +%T) packaging jmc - logging output to ${packageLog}"
-    mvn package --log-file "${packageLog}"
+    mvn ${JVM_ARGUMENTS} package --log-file "${packageLog}"
 
     if [[ "${OSTYPE}" =~ "linux"* ]]; then
         echo "You can now run jmc by calling \"${PROGNAME} --run\" or \"${BASEDIR}/products/org.openjdk.jmc/linux/gtk/${ARCH}/JDK\ Mission\ Control/jmc\""
@@ -142,7 +144,7 @@ function packageAgent() {
     }
 
     echo "$(date +%T) packaging jmc agent - logging output to ${packageLog}"
-    mvn package --log-file "${packageLog}"
+    mvn ${JVM_ARGUMENTS} package --log-file "${packageLog}"
 
     popd 1> /dev/null || {
         err_log "could not go to project root directory"
@@ -294,6 +296,9 @@ function parseArgs() {
             --runAgentConverterExample)
                 runAgentByClass "org.openjdk.jmc.agent.converters.test.InstrumentMeConverter"
                 ;;
+            --skipJDPMulticastTests)
+                JVM_ARGUMENTS="${JVM_ARGUMENTS} -DskipJDPMulticastTests=true"
+                ;;
             *)
                 err_log "unknown arguments: $@"
                 printHelp

core/tests/org.openjdk.jmc.jdp.test/src/test/java/org/openjdk/jmc/jdp/client/JDPClientTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
  * 
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -41,6 +41,7 @@
 import java.util.concurrent.TimeUnit;
 import java.util.logging.Logger;
 
+import org.junit.Assume;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -62,6 +63,7 @@ public void setUp() throws Exception {
 
 	@Test
 	public void testJDPClient() throws Exception {
+		Assume.assumeTrue(TestToolkit.areBroadcastingTestsEnabled());
 		JDPClient client = createDefaultClient();
 		JDPServer server = createDefaultServer();
 		client.start();
@@ -83,6 +85,7 @@ public void testJDPClient() throws Exception {
 
 	@Test
 	public void testChangePacket() throws Exception {
+		Assume.assumeTrue(TestToolkit.areBroadcastingTestsEnabled());
 		JDPClient client = createDefaultClient();
 		JDPServer server = createDefaultServer();
 		client.start();

core/tests/org.openjdk.jmc.jdp.test/src/test/java/org/openjdk/jmc/jdp/client/JDPJMXTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
  * 
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -39,6 +39,7 @@
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
 
+import org.junit.Assume;
 import org.junit.Before;
 import org.junit.Test;
 import org.openjdk.jmc.jdp.common.Configuration;
@@ -58,6 +59,7 @@ public void setUp() throws Exception {
 
 	@Test
 	public void testJDPClient() throws Exception {
+		Assume.assumeTrue(TestToolkit.areBroadcastingTestsEnabled());
 		JDPClient client = createDefaultClient();
 		JDPServer server = TestToolkit.createDefaultJMXJDPServer(discoverableID);
 		TestToolkit.printServerSettings(server);

core/tests/org.openjdk.jmc.jdp.test/src/test/java/org/openjdk/jmc/jdp/client/TestToolkit.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
  * 
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -32,9 +32,12 @@
  */
 package org.openjdk.jmc.jdp.client;
 
+import java.io.IOException;
 import java.io.UnsupportedEncodingException;
+import java.net.DatagramPacket;
 import java.net.InetAddress;
 import java.net.MalformedURLException;
+import java.net.MulticastSocket;
 import java.net.UnknownHostException;
 import java.security.SecureRandom;
 import java.util.logging.Level;
@@ -148,4 +151,65 @@ private static byte[] toBytes(String[] tmp) {
 		}
 		return bytes;
 	}
+
+	/**
+	 * See https://bugs.openjdk.java.net/browse/JMC-7539
+	 */
+	public static boolean areBroadcastingTestsEnabled() {
+		if (Boolean.getBoolean("skipJDPMulticastTests")) {
+			JDPClientTest.LOGGER.log(Level.INFO, "Broadcasting related tests are disabled");
+			return false;
+		}
+		if (!isBroadcastingPossible()) {
+			String os = System.getProperty("os.name").toLowerCase();
+			String helpMessage = ", you could try ";
+			String address = TEST_MULTICAST_ADDRESS.getCanonicalHostName();
+			if (os.startsWith("mac") || os.startsWith("darwin")) {
+				helpMessage += String.format("'sudo route add -host %s -interface en0'", address);
+			} else if (os.startsWith("linux")) {
+				helpMessage += String.format("'sudo ip route add %s dev eth0'", address);
+			} else if (os.startsWith("win")) {
+				helpMessage += String.format("'route add %s <gateway>' in a shell with administrator permissions",
+						address);
+			} else {
+				helpMessage = "";
+			}
+			JDPClientTest.LOGGER.log(Level.WARNING, "Broadcasting does not seem to be possible.\n"
+					+ "This is usually related to VPN. There are three possible ways to remedy this:\n"
+					+ "  1. Try to configure your VPN, or perhaps turn it off.\n"
+					+ "  2. Add a proper route for local multicast" + helpMessage + ".\n"
+					+ "  3. If the two above really can't be made to work, use -DskipJDPMulticastTests=true (with Java or maven)\n"
+					+ "     or --skipJDPMulticastTests (as first argument of the build script)");
+		}
+		return true;
+	}
+
+	private static boolean isBroadcastingPossible() {
+		InetAddress multiCastAddress = TEST_MULTICAST_ADDRESS;
+		int multiCastPort = 7711;
+		Thread thread = new Thread(() -> {
+			try (MulticastSocket ssocket = new MulticastSocket(multiCastPort)) {
+				ssocket.setTimeToLive(1);
+				ssocket.joinGroup(multiCastAddress);
+				final DatagramPacket dp = new DatagramPacket(new byte[] {1}, 1, multiCastAddress, multiCastPort);
+				while (true) {
+					ssocket.send(dp);
+					Thread.sleep(10);
+				}
+			} catch (InterruptedException | IOException e) {
+			}
+		});
+		thread.start();
+		try (MulticastSocket socket = new MulticastSocket(multiCastPort)) {
+			socket.joinGroup(multiCastAddress);
+			byte[] buffer = new byte[4096];
+			socket.setSoTimeout(300);
+			socket.receive(new DatagramPacket(buffer, buffer.length));
+			return true;
+		} catch (IOException e) {
+		} finally {
+			thread.interrupt();
+		}
+		return false;
+	}
 }