Merge branch '1328-reuse-port' into 'master'

Choose port in advance when providing wifi access point

Closes #1328

See merge request briar/briar!1228

bramble-android/src/main/java/org/briarproject/bramble/network/AndroidNetworkManager.java

@@ -32,6 +32,7 @@ import static android.content.Intent.ACTION_SCREEN_OFF;
 import static android.content.Intent.ACTION_SCREEN_ON;
 import static android.net.ConnectivityManager.CONNECTIVITY_ACTION;
 import static android.net.ConnectivityManager.TYPE_WIFI;
+import static android.net.wifi.p2p.WifiP2pManager.WIFI_P2P_THIS_DEVICE_CHANGED_ACTION;
 import static android.os.Build.VERSION.SDK_INT;
 import static android.os.PowerManager.ACTION_DEVICE_IDLE_MODE_CHANGED;
 import static java.util.concurrent.TimeUnit.MINUTES;
@@ -76,9 +77,9 @@ class AndroidNetworkManager implements NetworkManager, Service {
 		filter.addAction(ACTION_SCREEN_ON);
 		filter.addAction(ACTION_SCREEN_OFF);
 		filter.addAction(WIFI_AP_STATE_CHANGED_ACTION);
+		filter.addAction(WIFI_P2P_THIS_DEVICE_CHANGED_ACTION);
 		if (SDK_INT >= 23) filter.addAction(ACTION_DEVICE_IDLE_MODE_CHANGED);
 		appContext.registerReceiver(networkStateReceiver, filter);
-
 	}
 
 	@Override
@@ -136,7 +137,8 @@ class AndroidNetworkManager implements NetworkManager, Service {
 		}
 
 		private boolean isApEvent(@Nullable String action) {
-			return WIFI_AP_STATE_CHANGED_ACTION.equals(action);
+			return WIFI_AP_STATE_CHANGED_ACTION.equals(action) ||
+					WIFI_P2P_THIS_DEVICE_CHANGED_ACTION.equals(action);
 		}
 	}
 }

bramble-android/src/main/java/org/briarproject/bramble/plugin/tcp/AndroidLanTcpPlugin.java

@@ -40,19 +40,6 @@ class AndroidLanTcpPlugin extends LanTcpPlugin implements EventListener {
 	private static final Logger LOG =
 			getLogger(AndroidLanTcpPlugin.class.getName());
 
-	private static final byte[] WIFI_AP_ADDRESS_BYTES =
-			{(byte) 192, (byte) 168, 43, 1};
-	private static final InetAddress WIFI_AP_ADDRESS;
-
-	static {
-		try {
-			WIFI_AP_ADDRESS = InetAddress.getByAddress(WIFI_AP_ADDRESS_BYTES);
-		} catch (UnknownHostException e) {
-			// Should only be thrown if the address has an illegal length
-			throw new AssertionError(e);
-		}
-	}
-
 	private final Executor connectionStatusExecutor;
 	private final ConnectivityManager connectivityManager;
 	@Nullable
@@ -62,8 +49,9 @@ class AndroidLanTcpPlugin extends LanTcpPlugin implements EventListener {
 
 	AndroidLanTcpPlugin(Executor ioExecutor, Context appContext,
 			Backoff backoff, PluginCallback callback, int maxLatency,
-			int maxIdleTime) {
-		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime);
+			int maxIdleTime, int connectionTimeout) {
+		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime,
+				connectionTimeout);
 		// Don't execute more than one connection status check at a time
 		connectionStatusExecutor =
 				new PoliteExecutor("AndroidLanTcpPlugin", ioExecutor, 1);
@@ -79,6 +67,7 @@ class AndroidLanTcpPlugin extends LanTcpPlugin implements EventListener {
 	@Override
 	public void start() {
 		if (used.getAndSet(true)) throw new IllegalStateException();
+		initialisePortProperty();
 		running = true;
 		updateConnectionStatus();
 	}
@@ -103,8 +92,11 @@ class AndroidLanTcpPlugin extends LanTcpPlugin implements EventListener {
 		if (info != null && info.getIpAddress() != 0)
 			return singletonList(intToInetAddress(info.getIpAddress()));
 		// If we're running an access point, return its address
-		if (super.getLocalIpAddresses().contains(WIFI_AP_ADDRESS))
+		Collection<InetAddress> all = super.getLocalIpAddresses();
+		if (all.contains(WIFI_AP_ADDRESS))
 			return singletonList(WIFI_AP_ADDRESS);
+		if (all.contains(WIFI_DIRECT_AP_ADDRESS))
+			return singletonList(WIFI_DIRECT_AP_ADDRESS);
 		// No suitable addresses
 		return emptyList();
 	}
@@ -145,7 +137,8 @@ class AndroidLanTcpPlugin extends LanTcpPlugin implements EventListener {
 		connectionStatusExecutor.execute(() -> {
 			if (!running) return;
 			Collection<InetAddress> addrs = getLocalIpAddresses();
-			if (addrs.contains(WIFI_AP_ADDRESS)) {
+			if (addrs.contains(WIFI_AP_ADDRESS)
+					|| addrs.contains(WIFI_DIRECT_AP_ADDRESS)) {
 				LOG.info("Providing wifi hotspot");
 				// There's no corresponding Network object and thus no way
 				// to get a suitable socket factory, so we won't be able to

bramble-android/src/main/java/org/briarproject/bramble/plugin/tcp/AndroidLanTcpPluginFactory.java

@@ -21,10 +21,11 @@ import static org.briarproject.bramble.api.plugin.LanTcpConstants.ID;
 @NotNullByDefault
 public class AndroidLanTcpPluginFactory implements DuplexPluginFactory {
 
-	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
-	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
-	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
-	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
+	private static final int MAX_LATENCY = 30_000; // 30 seconds
+	private static final int MAX_IDLE_TIME = 30_000; // 30 seconds
+	private static final int CONNECTION_TIMEOUT = 3_000; // 3 seconds
+	private static final int MIN_POLLING_INTERVAL = 60_000; // 1 minute
+	private static final int MAX_POLLING_INTERVAL = 600_000; // 10 mins
 	private static final double BACKOFF_BASE = 1.2;
 
 	private final Executor ioExecutor;
@@ -55,7 +56,8 @@ public class AndroidLanTcpPluginFactory implements DuplexPluginFactory {
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
 		AndroidLanTcpPlugin plugin = new AndroidLanTcpPlugin(ioExecutor,
-				appContext, backoff, callback, MAX_LATENCY, MAX_IDLE_TIME);
+				appContext, backoff, callback, MAX_LATENCY, MAX_IDLE_TIME,
+				CONNECTION_TIMEOUT);
 		eventBus.addListener(plugin);
 		return plugin;
 	}

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/LanTcpConstants.java

@@ -4,10 +4,10 @@ public interface LanTcpConstants {
 
 	TransportId ID = new TransportId("org.briarproject.bramble.lan");
 
-	// a transport property (shared with contacts)
+	// Transport properties (shared with contacts)
 	String PROP_IP_PORTS = "ipPorts";
+	String PROP_PORT = "port";
 
-	// a local setting
+	// A local setting
 	String PREF_LAN_IP_PORTS = "ipPorts";
-
 }

bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/LanTcpPlugin.java

@@ -24,11 +24,14 @@ import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Random;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;
 
+import javax.annotation.Nullable;
+
+import static java.lang.Integer.parseInt;
 import static java.util.Collections.addAll;
-import static java.util.Collections.emptyList;
 import static java.util.Collections.sort;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
@@ -37,6 +40,7 @@ import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.TR
 import static org.briarproject.bramble.api.plugin.LanTcpConstants.ID;
 import static org.briarproject.bramble.api.plugin.LanTcpConstants.PREF_LAN_IP_PORTS;
 import static org.briarproject.bramble.api.plugin.LanTcpConstants.PROP_IP_PORTS;
+import static org.briarproject.bramble.api.plugin.LanTcpConstants.PROP_PORT;
 import static org.briarproject.bramble.util.ByteUtils.MAX_16_BIT_UNSIGNED;
 import static org.briarproject.bramble.util.PrivacyUtils.scrubSocketAddress;
 import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
@@ -53,9 +57,33 @@ class LanTcpPlugin extends TcpPlugin {
 	private static final int MAX_ADDRESSES = 4;
 	private static final String SEPARATOR = ",";
 
+	/**
+	 * The IP address of an Android device providing a wifi access point.
+	 */
+	protected static final InetAddress WIFI_AP_ADDRESS;
+
+	/**
+	 * The IP address of an Android device providing a wifi direct
+	 * legacy mode access point.
+	 */
+	protected static final InetAddress WIFI_DIRECT_AP_ADDRESS;
+
+	static {
+		try {
+			WIFI_AP_ADDRESS = InetAddress.getByAddress(
+					new byte[] {(byte) 192, (byte) 168, 43, 1});
+			WIFI_DIRECT_AP_ADDRESS = InetAddress.getByAddress(
+					new byte[] {(byte) 192, (byte) 168, 49, 1});
+		} catch (UnknownHostException e) {
+			// Should only be thrown if the address has an illegal length
+			throw new AssertionError(e);
+		}
+	}
+
 	LanTcpPlugin(Executor ioExecutor, Backoff backoff, PluginCallback callback,
-			int maxLatency, int maxIdleTime) {
-		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime);
+			int maxLatency, int maxIdleTime, int connectionTimeout) {
+		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime,
+				connectionTimeout);
 	}
 
 	@Override
@@ -64,19 +92,43 @@ class LanTcpPlugin extends TcpPlugin {
 	}
 
 	@Override
-	protected List<InetSocketAddress> getLocalSocketAddresses() {
-		// Use the same address and port as last time if available
+	public void start() {
+		if (used.getAndSet(true)) throw new IllegalStateException();
+		initialisePortProperty();
+		running = true;
+		bind();
+	}
+
+	protected void initialisePortProperty() {
 		TransportProperties p = callback.getLocalProperties();
+		if (isNullOrEmpty(p.get(PROP_PORT))) {
+			int port = new Random().nextInt(32768) + 32768;
+			p.put(PROP_PORT, String.valueOf(port));
+			callback.mergeLocalProperties(p);
+		}
+	}
+
+	@Override
+	protected List<InetSocketAddress> getLocalSocketAddresses() {
+		TransportProperties p = callback.getLocalProperties();
+		int port = parsePortProperty(p.get(PROP_PORT));
 		String oldIpPorts = p.get(PROP_IP_PORTS);
 		List<InetSocketAddress> olds = parseSocketAddresses(oldIpPorts);
 		List<InetSocketAddress> locals = new ArrayList<>();
 		for (InetAddress local : getLocalIpAddresses()) {
 			if (isAcceptableAddress(local)) {
-				// If this is the old address, try to use the same port
+				// If we've used this address before, try to use the same port
+				boolean reused = false;
 				for (InetSocketAddress old : olds) {
-					if (old.getAddress().equals(local))
+					if (old.getAddress().equals(local)) {
 						locals.add(new InetSocketAddress(local, old.getPort()));
+						reused = true;
+						break;
+					}
 				}
+				// Otherwise try to use our preferred port
+				if (!reused) locals.add(new InetSocketAddress(local, port));
+				// Fall back to any available port
 				locals.add(new InetSocketAddress(local, 0));
 			}
 		}
@@ -84,11 +136,19 @@ class LanTcpPlugin extends TcpPlugin {
 		return locals;
 	}
 
+	private int parsePortProperty(@Nullable String portProperty) {
+		if (isNullOrEmpty(portProperty)) return 0;
+		try {
+			return parseInt(portProperty);
+		} catch (NumberFormatException e) {
+			return 0;
+		}
+	}
+
 	private List<InetSocketAddress> parseSocketAddresses(String ipPorts) {
-		if (isNullOrEmpty(ipPorts)) return emptyList();
-		String[] split = ipPorts.split(SEPARATOR);
 		List<InetSocketAddress> addresses = new ArrayList<>();
-		for (String ipPort : split) {
+		if (isNullOrEmpty(ipPorts)) return addresses;
+		for (String ipPort : ipPorts.split(SEPARATOR)) {
 			InetSocketAddress a = parseSocketAddress(ipPort);
 			if (a != null) addresses.add(a);
 		}
@@ -132,7 +192,20 @@ class LanTcpPlugin extends TcpPlugin {
 	@Override
 	protected List<InetSocketAddress> getRemoteSocketAddresses(
 			TransportProperties p) {
-		return parseSocketAddresses(p.get(PROP_IP_PORTS));
+		String ipPorts = p.get(PROP_IP_PORTS);
+		List<InetSocketAddress> remotes = parseSocketAddresses(ipPorts);
+		int port = parsePortProperty(p.get(PROP_PORT));
+		// If the contact has a preferred port, we can guess their IP:port when
+		// they're providing a wifi access point
+		if (port != 0) {
+			InetSocketAddress wifiAp =
+					new InetSocketAddress(WIFI_AP_ADDRESS, port);
+			if (!remotes.contains(wifiAp)) remotes.add(wifiAp);
+			InetSocketAddress wifiDirectAp =
+					new InetSocketAddress(WIFI_DIRECT_AP_ADDRESS, port);
+			if (!remotes.contains(wifiDirectAp)) remotes.add(wifiDirectAp);
+		}
+		return remotes;
 	}
 
 	private boolean isAcceptableAddress(InetAddress a) {
@@ -250,7 +323,7 @@ class LanTcpPlugin extends TcpPlugin {
 				LOG.info("Connecting to " + scrubSocketAddress(remote));
 			Socket s = createSocket();
 			s.bind(new InetSocketAddress(socket.getInetAddress(), 0));
-			s.connect(remote);
+			s.connect(remote, connectionTimeout);
 			s.setSoTimeout(socketTimeout);
 			if (LOG.isLoggable(INFO))
 				LOG.info("Connected to " + scrubSocketAddress(remote));

bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/LanTcpPluginFactory.java

@@ -18,10 +18,11 @@ import static org.briarproject.bramble.api.plugin.LanTcpConstants.ID;
 @NotNullByDefault
 public class LanTcpPluginFactory implements DuplexPluginFactory {
 
-	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
-	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
-	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
-	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
+	private static final int MAX_LATENCY = 30_000; // 30 seconds
+	private static final int MAX_IDLE_TIME = 30_000; // 30 seconds
+	private static final int CONNECTION_TIMEOUT = 3_000; // 3 seconds
+	private static final int MIN_POLLING_INTERVAL = 60_000; // 1 minute
+	private static final int MAX_POLLING_INTERVAL = 600_000; // 10 mins
 	private static final double BACKOFF_BASE = 1.2;
 
 	private final Executor ioExecutor;
@@ -48,6 +49,6 @@ public class LanTcpPluginFactory implements DuplexPluginFactory {
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
 		return new LanTcpPlugin(ioExecutor, backoff, callback, MAX_LATENCY,
-				MAX_IDLE_TIME);
+				MAX_IDLE_TIME, CONNECTION_TIMEOUT);
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/TcpPlugin.java

@@ -58,7 +58,8 @@ abstract class TcpPlugin implements DuplexPlugin {
 	protected final Executor ioExecutor, bindExecutor;
 	protected final Backoff backoff;
 	protected final PluginCallback callback;
-	protected final int maxLatency, maxIdleTime, socketTimeout;
+	protected final int maxLatency, maxIdleTime;
+	protected final int connectionTimeout, socketTimeout;
 	protected final AtomicBoolean used = new AtomicBoolean(false);
 
 	protected volatile boolean running = false;
@@ -86,15 +87,17 @@ abstract class TcpPlugin implements DuplexPlugin {
 	/**
 	 * Returns true if connections to the given address can be attempted.
 	 */
+	@SuppressWarnings("BooleanMethodIsAlwaysInverted")
 	protected abstract boolean isConnectable(InetSocketAddress remote);
 
 	TcpPlugin(Executor ioExecutor, Backoff backoff, PluginCallback callback,
-			int maxLatency, int maxIdleTime) {
+			int maxLatency, int maxIdleTime, int connectionTimeout) {
 		this.ioExecutor = ioExecutor;
 		this.backoff = backoff;
 		this.callback = callback;
 		this.maxLatency = maxLatency;
 		this.maxIdleTime = maxIdleTime;
+		this.connectionTimeout = connectionTimeout;
 		if (maxIdleTime > Integer.MAX_VALUE / 2)
 			socketTimeout = Integer.MAX_VALUE;
 		else socketTimeout = maxIdleTime * 2;
@@ -231,6 +234,11 @@ abstract class TcpPlugin implements DuplexPlugin {
 	public DuplexTransportConnection createConnection(TransportProperties p) {
 		if (!isRunning()) return null;
 		for (InetSocketAddress remote : getRemoteSocketAddresses(p)) {
+			// Don't try to connect to our own address
+			if (!canConnectToOwnAddress() &&
+					remote.getAddress().equals(socket.getInetAddress())) {
+				continue;
+			}
 			if (!isConnectable(remote)) {
 				if (LOG.isLoggable(INFO)) {
 					SocketAddress local = socket.getLocalSocketAddress();
@@ -245,7 +253,7 @@ abstract class TcpPlugin implements DuplexPlugin {
 					LOG.info("Connecting to " + scrubSocketAddress(remote));
 				Socket s = createSocket();
 				s.bind(new InetSocketAddress(socket.getInetAddress(), 0));
-				s.connect(remote);
+				s.connect(remote, connectionTimeout);
 				s.setSoTimeout(socketTimeout);
 				if (LOG.isLoggable(INFO))
 					LOG.info("Connected to " + scrubSocketAddress(remote));
@@ -259,6 +267,11 @@ abstract class TcpPlugin implements DuplexPlugin {
 		return null;
 	}
 
+	// Override for testing
+	protected boolean canConnectToOwnAddress() {
+		return false;
+	}
+
 	protected Socket createSocket() throws IOException {
 		return new Socket();
 	}

bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/WanTcpPlugin.java

@@ -29,8 +29,10 @@ class WanTcpPlugin extends TcpPlugin {
 	private volatile MappingResult mappingResult;
 
 	WanTcpPlugin(Executor ioExecutor, Backoff backoff, PortMapper portMapper,
-			PluginCallback callback, int maxLatency, int maxIdleTime) {
-		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime);
+			PluginCallback callback, int maxLatency, int maxIdleTime,
+			int connectionTimeout) {
+		super(ioExecutor, backoff, callback, maxLatency, maxIdleTime,
+				connectionTimeout);
 		this.portMapper = portMapper;
 	}
 

bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/WanTcpPluginFactory.java

@@ -19,10 +19,11 @@ import static org.briarproject.bramble.api.plugin.WanTcpConstants.ID;
 @NotNullByDefault
 public class WanTcpPluginFactory implements DuplexPluginFactory {
 
-	private static final int MAX_LATENCY = 30 * 1000; // 30 seconds
-	private static final int MAX_IDLE_TIME = 30 * 1000; // 30 seconds
-	private static final int MIN_POLLING_INTERVAL = 60 * 1000; // 1 minute
-	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
+	private static final int MAX_LATENCY = 30_000; // 30 seconds
+	private static final int MAX_IDLE_TIME = 30_000; // 30 seconds
+	private static final int CONNECTION_TIMEOUT = 30_000; // 30 seconds
+	private static final int MIN_POLLING_INTERVAL = 60_000; // 1 minute
+	private static final int MAX_POLLING_INTERVAL = 600_000; // 10 mins
 	private static final double BACKOFF_BASE = 1.2;
 
 	private final Executor ioExecutor;
@@ -52,6 +53,6 @@ public class WanTcpPluginFactory implements DuplexPluginFactory {
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
 		return new WanTcpPlugin(ioExecutor, backoff,
 				new PortMapperImpl(shutdownManager), callback, MAX_LATENCY,
-				MAX_IDLE_TIME);
+				MAX_IDLE_TIME, CONNECTION_TIMEOUT);
 	}
 }

bramble-core/src/test/java/org/briarproject/bramble/plugin/tcp/LanTcpPluginTest.java

@@ -7,12 +7,12 @@ import org.briarproject.bramble.api.plugin.Backoff;
 import org.briarproject.bramble.api.plugin.PluginCallback;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
-import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.plugin.tcp.LanTcpPlugin.LanAddressComparator;
 import org.briarproject.bramble.test.BrambleTestCase;
+import org.junit.Before;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -37,17 +37,29 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assume.assumeTrue;
 
 public class LanTcpPluginTest extends BrambleTestCase {
 
 	private final Backoff backoff = new TestBackoff();
 	private final ExecutorService ioExecutor = newCachedThreadPool();
 
+	private Callback callback = null;
+	private LanTcpPlugin plugin = null;
+
+	@Before
+	public void setUp() {
+		callback = new Callback();
+		plugin = new LanTcpPlugin(ioExecutor, backoff, callback, 0, 0, 1000) {
+			@Override
+			protected boolean canConnectToOwnAddress() {
+				return true;
+			}
+		};
+	}
+
 	@Test
 	public void testAddressesAreOnSameLan() {
-		Callback callback = new Callback();
-		LanTcpPlugin plugin = new LanTcpPlugin(ioExecutor, backoff, callback,
-				0, 0);
 		// Local and remote in 10.0.0.0/8 should return true
 		assertTrue(plugin.addressesAreOnSameLan(makeAddress(10, 0, 0, 0),
 				makeAddress(10, 255, 255, 255)));
@@ -93,13 +105,7 @@ public class LanTcpPluginTest extends BrambleTestCase {
 
 	@Test
 	public void testIncomingConnection() throws Exception {
-		if (!systemHasLocalIpv4Address()) {
-			System.err.println("WARNING: Skipping test, no local IPv4 address");
-			return;
-		}
-		Callback callback = new Callback();
-		DuplexPlugin plugin = new LanTcpPlugin(ioExecutor, backoff, callback,
-				0, 0);
+		assumeTrue(systemHasLocalIpv4Address());
 		plugin.start();
 		// The plugin should have bound a socket and stored the port number
 		assertTrue(callback.propertiesLatch.await(5, SECONDS));
@@ -128,13 +134,7 @@ public class LanTcpPluginTest extends BrambleTestCase {
 
 	@Test
 	public void testOutgoingConnection() throws Exception {
-		if (!systemHasLocalIpv4Address()) {
-			System.err.println("WARNING: Skipping test, no local IPv4 address");
-			return;
-		}
-		Callback callback = new Callback();
-		DuplexPlugin plugin = new LanTcpPlugin(ioExecutor, backoff, callback,
-				0, 0);
+		assumeTrue(systemHasLocalIpv4Address());
 		plugin.start();
 		// The plugin should have bound a socket and stored the port number
 		assertTrue(callback.propertiesLatch.await(5, SECONDS));
@@ -177,13 +177,7 @@ public class LanTcpPluginTest extends BrambleTestCase {
 
 	@Test
 	public void testIncomingKeyAgreementConnection() throws Exception {
-		if (!systemHasLocalIpv4Address()) {
-			System.err.println("WARNING: Skipping test, no local IPv4 address");
-			return;
-		}
-		Callback callback = new Callback();
-		DuplexPlugin plugin = new LanTcpPlugin(ioExecutor, backoff, callback,
-				0, 0);
+		assumeTrue(systemHasLocalIpv4Address());
 		plugin.start();
 		assertTrue(callback.propertiesLatch.await(5, SECONDS));
 		KeyAgreementListener kal =
@@ -225,13 +219,7 @@ public class LanTcpPluginTest extends BrambleTestCase {
 
 	@Test
 	public void testOutgoingKeyAgreementConnection() throws Exception {
-		if (!systemHasLocalIpv4Address()) {
-			System.err.println("WARNING: Skipping test, no local IPv4 address");
-			return;
-		}
-		Callback callback = new Callback();
-		DuplexPlugin plugin = new LanTcpPlugin(ioExecutor, backoff, callback,
-				0, 0);
+		assumeTrue(systemHasLocalIpv4Address());
 		plugin.start();
 		// The plugin should have bound a socket and stored the port number
 		assertTrue(callback.propertiesLatch.await(5, SECONDS));
@@ -340,7 +328,9 @@ public class LanTcpPluginTest extends BrambleTestCase {
 	@NotNullByDefault
 	private static class Callback implements PluginCallback {
 
-		private final CountDownLatch propertiesLatch = new CountDownLatch(1);
+		// Properties will be stored twice: the preferred port at startup,
+		// and the IP:port when the server socket is bound
+		private final CountDownLatch propertiesLatch = new CountDownLatch(2);
 		private final CountDownLatch connectionsLatch = new CountDownLatch(1);
 		private final TransportProperties local = new TransportProperties();
 

briar-core/src/main/java/org/briarproject/briar/test/TestDataCreatorImpl.java

@@ -230,6 +230,8 @@ public class TestDataCreatorImpl implements TestDataCreator {
 			sb.append(getRandomLanAddress());
 		}
 		lan.put(LanTcpConstants.PROP_IP_PORTS, sb.toString());
+		String port = String.valueOf(getRandomPortNumber());
+		lan.put(LanTcpConstants.PROP_PORT, port);
 		props.put(LanTcpConstants.ID, lan);
 
 		// Tor
@@ -266,18 +268,21 @@ public class TestDataCreatorImpl implements TestDataCreator {
 			sb.append("10.");
 			sb.append(random.nextInt(2)).append('.');
 			sb.append(random.nextInt(2)).append('.');
-			sb.append(random.nextInt(256));
+			sb.append(random.nextInt(255));
 		} else {
 			sb.append("192.168.");
 			sb.append(random.nextInt(2)).append('.');
-			sb.append(random.nextInt(256));
+			sb.append(random.nextInt(255));
 		}
 		// port
-		sb.append(":");
-		sb.append(1024 + random.nextInt(50000));
+		sb.append(':').append(getRandomPortNumber());
 		return sb.toString();
 	}
 
+	private int getRandomPortNumber() {
+		return 32768 + random.nextInt(32768);
+	}
+
 	private String getRandomTorAddress() {
 		StringBuilder sb = new StringBuilder();
 		// address