Merge branch 'discover-bt-address-from-incoming-connection' into 'master'

Discover remote Bluetooth address from connection

See merge request briar/briar!1244

bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothTransportConnection.java

@@ -10,6 +10,9 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 
+import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_ADDRESS;
+import static org.briarproject.bramble.util.AndroidUtils.isValidBluetoothAddress;
+
 @NotNullByDefault
 class AndroidBluetoothTransportConnection
 		extends AbstractDuplexTransportConnection {
@@ -23,6 +26,8 @@ class AndroidBluetoothTransportConnection
 		super(plugin);
 		this.connectionManager = connectionManager;
 		this.socket = socket;
+		String address = socket.getRemoteDevice().getAddress();
+		if (isValidBluetoothAddress(address)) remote.put(PROP_ADDRESS, address);
 	}
 
 	@Override

bramble-android/src/main/java/org/briarproject/bramble/util/AndroidUtils.java

@@ -71,7 +71,7 @@ public class AndroidUtils {
 		return new Pair<>("", "");
 	}
 
-	private static boolean isValidBluetoothAddress(@Nullable String address) {
+	public static boolean isValidBluetoothAddress(@Nullable String address) {
 		return !StringUtils.isNullOrEmpty(address)
 				&& BluetoothAdapter.checkBluetoothAddress(address)
 				&& !address.equals(FAKE_BLUETOOTH_ADDRESS);

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/AbstractDuplexTransportConnection.java

@@ -4,6 +4,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
+import org.briarproject.bramble.api.properties.TransportProperties;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -14,6 +15,8 @@ import java.util.concurrent.atomic.AtomicBoolean;
 public abstract class AbstractDuplexTransportConnection
 		implements DuplexTransportConnection {
 
+	protected final TransportProperties remote = new TransportProperties();
+
 	private final Plugin plugin;
 	private final Reader reader;
 	private final Writer writer;
@@ -44,6 +47,11 @@ public abstract class AbstractDuplexTransportConnection
 		return writer;
 	}
 
+	@Override
+	public TransportProperties getRemoteProperties() {
+		return remote;
+	}
+
 	private class Reader implements TransportConnectionReader {
 
 		@Override

bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/DuplexTransportConnection.java

@@ -3,6 +3,7 @@ package org.briarproject.bramble.api.plugin.duplex;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
+import org.briarproject.bramble.api.properties.TransportProperties;
 
 /**
  * An interface for reading and writing data over a duplex transport. The
@@ -23,4 +24,10 @@ public interface DuplexTransportConnection {
 	 * for writing to the connection.
 	 */
 	TransportConnectionWriter getWriter();
+
+	/**
+	 * Returns a possibly empty set of {@link TransportProperties} describing
+	 * the remote peer.
+	 */
+	TransportProperties getRemoteProperties();
 }

bramble-api/src/main/java/org/briarproject/bramble/api/properties/TransportPropertyConstants.java

@@ -11,4 +11,28 @@ public interface TransportPropertyConstants {
 	 * The maximum length of a property's key or value in UTF-8 bytes.
 	 */
 	int MAX_PROPERTY_LENGTH = 100;
+
+	/**
+	 * Message metadata key for the transport ID of a local or remote update,
+	 * as a BDF string.
+	 */
+	String MSG_KEY_TRANSPORT_ID = "transportId";
+
+	/**
+	 * Message metadata key for the version number of a local or remote update,
+	 * as a BDF long.
+	 */
+	String MSG_KEY_VERSION = "version";
+
+	/**
+	 * Message metadata key for whether an update is local or remote, as a BDF
+	 * boolean.
+	 */
+	String MSG_KEY_LOCAL = "local";
+
+	/**
+	 * Group metadata key for any discovered transport properties of the
+	 * contact, as a BDF dictionary.
+	 */
+	String GROUP_KEY_DISCOVERED = "discovered";
 }

bramble-api/src/main/java/org/briarproject/bramble/api/properties/TransportPropertyManager.java

@@ -34,6 +34,14 @@ public interface TransportPropertyManager {
 	void addRemoteProperties(Transaction txn, ContactId c,
 			Map<TransportId, TransportProperties> props) throws DbException;
 
+	/**
+	 * Stores the given properties discovered from an incoming transport
+	 * connection. They will be overridden by any properties received while
+	 * adding the contact or synced from the contact.
+	 */
+	void addRemotePropertiesFromConnection(ContactId c, TransportId t,
+			TransportProperties props) throws DbException;
+
 	/**
 	 * Returns the local transport properties for all transports.
 	 */

bramble-core/src/main/java/org/briarproject/bramble/plugin/ConnectionManagerImpl.java

@@ -15,6 +15,8 @@ import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
+import org.briarproject.bramble.api.properties.TransportProperties;
+import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.sync.SyncSession;
 import org.briarproject.bramble.api.sync.SyncSessionFactory;
 import org.briarproject.bramble.api.transport.KeyManager;
@@ -52,6 +54,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 	private final HandshakeManager handshakeManager;
 	private final ContactExchangeManager contactExchangeManager;
 	private final ConnectionRegistry connectionRegistry;
+	private final TransportPropertyManager transportPropertyManager;
 
 	@Inject
 	ConnectionManagerImpl(@IoExecutor Executor ioExecutor,
@@ -60,7 +63,8 @@ class ConnectionManagerImpl implements ConnectionManager {
 			SyncSessionFactory syncSessionFactory,
 			HandshakeManager handshakeManager,
 			ContactExchangeManager contactExchangeManager,
-			ConnectionRegistry connectionRegistry) {
+			ConnectionRegistry connectionRegistry,
+			TransportPropertyManager transportPropertyManager) {
 		this.ioExecutor = ioExecutor;
 		this.keyManager = keyManager;
 		this.streamReaderFactory = streamReaderFactory;
@@ -69,6 +73,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 		this.handshakeManager = handshakeManager;
 		this.contactExchangeManager = contactExchangeManager;
 		this.connectionRegistry = connectionRegistry;
+		this.transportPropertyManager = transportPropertyManager;
 	}
 
 	@Override
@@ -269,6 +274,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 		private final TransportId transportId;
 		private final TransportConnectionReader reader;
 		private final TransportConnectionWriter writer;
+		private final TransportProperties remote;
 
 		@Nullable
 		private volatile SyncSession outgoingSession = null;
@@ -278,6 +284,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 			this.transportId = transportId;
 			reader = connection.getReader();
 			writer = connection.getWriter();
+			remote = connection.getRemoteProperties();
 		}
 
 		@Override
@@ -313,13 +320,16 @@ class ConnectionManagerImpl implements ConnectionManager {
 			// Start the outgoing session on another thread
 			ioExecutor.execute(() -> runOutgoingSession(contactId));
 			try {
+				// Store any transport properties discovered from the connection
+				transportPropertyManager.addRemotePropertiesFromConnection(
+						contactId, transportId, remote);
 				// Create and run the incoming session
 				createIncomingSession(ctx, reader).run();
 				reader.dispose(false, true);
 				// Interrupt the outgoing session so it finishes cleanly
 				SyncSession out = outgoingSession;
 				if (out != null) out.interrupt();
-			} catch (IOException e) {
+			} catch (DbException | IOException e) {
 				logException(LOG, WARNING, e);
 				onReadError(true);
 			} finally {
@@ -375,6 +385,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 		private final TransportId transportId;
 		private final TransportConnectionReader reader;
 		private final TransportConnectionWriter writer;
+		private final TransportProperties remote;
 
 		@Nullable
 		private volatile SyncSession outgoingSession = null;
@@ -385,6 +396,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 			this.transportId = transportId;
 			reader = connection.getReader();
 			writer = connection.getWriter();
+			remote = connection.getRemoteProperties();
 		}
 
 		@Override
@@ -461,13 +473,16 @@ class ConnectionManagerImpl implements ConnectionManager {
 			connectionRegistry.registerConnection(contactId, transportId,
 					false);
 			try {
+				// Store any transport properties discovered from the connection
+				transportPropertyManager.addRemotePropertiesFromConnection(
+						contactId, transportId, remote);
 				// Create and run the incoming session
 				createIncomingSession(ctx, reader).run();
 				reader.dispose(false, true);
 				// Interrupt the outgoing session so it finishes cleanly
 				SyncSession out = outgoingSession;
 				if (out != null) out.interrupt();
-			} catch (IOException e) {
+			} catch (DbException | IOException e) {
 				logException(LOG, WARNING, e);
 				onReadError();
 			} finally {

bramble-core/src/main/java/org/briarproject/bramble/properties/TransportPropertyManagerImpl.java

@@ -37,6 +37,11 @@ import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.GROUP_KEY_DISCOVERED;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MSG_KEY_LOCAL;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MSG_KEY_TRANSPORT_ID;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MSG_KEY_VERSION;
+
 @Immutable
 @NotNullByDefault
 class TransportPropertyManagerImpl implements TransportPropertyManager,
@@ -111,10 +116,10 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 		try {
 			// Find the latest update for this transport, if any
 			BdfDictionary d = metadataParser.parse(meta);
-			TransportId t = new TransportId(d.getString("transportId"));
+			TransportId t = new TransportId(d.getString(MSG_KEY_TRANSPORT_ID));
 			LatestUpdate latest = findLatest(txn, m.getGroupId(), t, false);
 			if (latest != null) {
-				if (d.getLong("version") > latest.version) {
+				if (d.getLong(MSG_KEY_VERSION) > latest.version) {
 					// This update is newer - delete the previous update
 					db.deleteMessage(txn, latest.messageId);
 					db.deleteMessageMetadata(txn, latest.messageId);
@@ -140,6 +145,27 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 		}
 	}
 
+	@Override
+	public void addRemotePropertiesFromConnection(ContactId c, TransportId t,
+			TransportProperties props) throws DbException {
+		if (props.isEmpty()) return;
+		try {
+			db.transaction(false, txn -> {
+				Group g = getContactGroup(db.getContact(txn, c));
+				BdfDictionary meta = clientHelper.getGroupMetadataAsDictionary(
+						txn, g.getId());
+				BdfDictionary discovered =
+						meta.getOptionalDictionary(GROUP_KEY_DISCOVERED);
+				if (discovered == null) discovered = new BdfDictionary();
+				discovered.putAll(props);
+				meta.put(GROUP_KEY_DISCOVERED, discovered);
+				clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
+			});
+		} catch (FormatException e) {
+			throw new DbException(e);
+		}
+	}
+
 	@Override
 	public Map<TransportId, TransportProperties> getLocalProperties()
 			throws DbException {
@@ -203,12 +229,26 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 		Group g = getContactGroup(c);
 		try {
 			// Find the latest remote update
+			TransportProperties remote;
 			LatestUpdate latest = findLatest(txn, g.getId(), t, false);
-			if (latest == null) return new TransportProperties();
-			// Retrieve and parse the latest remote properties
-			BdfList message =
-					clientHelper.getMessageAsList(txn, latest.messageId);
-			return parseProperties(message);
+			if (latest == null) {
+				remote = new TransportProperties();
+			} else {
+				// Retrieve and parse the latest remote properties
+				BdfList message =
+						clientHelper.getMessageAsList(txn, latest.messageId);
+				remote = parseProperties(message);
+			}
+			// Merge in any discovered properties
+			BdfDictionary meta =
+					clientHelper.getGroupMetadataAsDictionary(txn, g.getId());
+			BdfDictionary d = meta.getOptionalDictionary(GROUP_KEY_DISCOVERED);
+			if (d == null) return remote;
+			TransportProperties merged =
+					clientHelper.parseAndValidateTransportProperties(d);
+			// Received properties override discovered properties
+			merged.putAll(remote);
+			return merged;
 		} catch (FormatException e) {
 			throw new DbException(e);
 		}
@@ -281,9 +321,9 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 			long now = clock.currentTimeMillis();
 			Message m = clientHelper.createMessage(g, now, body);
 			BdfDictionary meta = new BdfDictionary();
-			meta.put("transportId", t.getString());
-			meta.put("version", version);
-			meta.put("local", local);
+			meta.put(MSG_KEY_TRANSPORT_ID, t.getString());
+			meta.put(MSG_KEY_VERSION, version);
+			meta.put(MSG_KEY_LOCAL, local);
 			clientHelper.addLocalMessage(txn, m, meta, shared, false);
 		} catch (FormatException e) {
 			throw new RuntimeException(e);
@@ -302,8 +342,9 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				.getMessageMetadataAsDictionary(txn, localGroup.getId());
 		for (Entry<MessageId, BdfDictionary> e : metadata.entrySet()) {
 			BdfDictionary meta = e.getValue();
-			TransportId t = new TransportId(meta.getString("transportId"));
-			long version = meta.getLong("version");
+			TransportId t =
+					new TransportId(meta.getString(MSG_KEY_TRANSPORT_ID));
+			long version = meta.getLong(MSG_KEY_VERSION);
 			latestUpdates.put(t, new LatestUpdate(e.getKey(), version));
 		}
 		return latestUpdates;
@@ -316,9 +357,10 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				clientHelper.getMessageMetadataAsDictionary(txn, g);
 		for (Entry<MessageId, BdfDictionary> e : metadata.entrySet()) {
 			BdfDictionary meta = e.getValue();
-			if (meta.getString("transportId").equals(t.getString())
-					&& meta.getBoolean("local") == local) {
-				return new LatestUpdate(e.getKey(), meta.getLong("version"));
+			if (meta.getString(MSG_KEY_TRANSPORT_ID).equals(t.getString())
+					&& meta.getBoolean(MSG_KEY_LOCAL) == local) {
+				return new LatestUpdate(e.getKey(),
+						meta.getLong(MSG_KEY_VERSION));
 			}
 		}
 		return null;

bramble-core/src/test/java/org/briarproject/bramble/properties/TransportPropertyManagerImplTest.java

@@ -24,14 +24,18 @@ import org.briarproject.bramble.test.DbExpectations;
 import org.jmock.Expectations;
 import org.junit.Test;
 
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
 import static java.util.Arrays.asList;
+import static java.util.Collections.emptyMap;
 import static java.util.Collections.singletonList;
 import static java.util.Collections.singletonMap;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.GROUP_KEY_DISCOVERED;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MSG_KEY_LOCAL;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MSG_KEY_TRANSPORT_ID;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MSG_KEY_VERSION;
 import static org.briarproject.bramble.api.properties.TransportPropertyManager.CLIENT_ID;
 import static org.briarproject.bramble.api.properties.TransportPropertyManager.MAJOR_VERSION;
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
@@ -186,25 +190,25 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		Message message = getMessage(contactGroupId);
 		Metadata meta = new Metadata();
 		BdfDictionary metaDictionary = BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 2),
-				new BdfEntry("local", false)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 2),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		);
 		Map<MessageId, BdfDictionary> messageMetadata =
 				new LinkedHashMap<>();
 		// A remote update for another transport should be ignored
 		MessageId barUpdateId = new MessageId(getRandomId());
 		messageMetadata.put(barUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "bar"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", false)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "bar"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		));
 		// A local update for the same transport should be ignored
 		MessageId localUpdateId = new MessageId(getRandomId());
 		messageMetadata.put(localUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", true)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, true)
 		));
 
 		context.checking(new Expectations() {{
@@ -228,18 +232,18 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		Metadata meta = new Metadata();
 		// Version 4 is being delivered
 		BdfDictionary metaDictionary = BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 4),
-				new BdfEntry("local", false)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 4),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		);
 		Map<MessageId, BdfDictionary> messageMetadata =
 				new LinkedHashMap<>();
 		// An older remote update for the same transport should be deleted
 		MessageId fooVersion3 = new MessageId(getRandomId());
 		messageMetadata.put(fooVersion3, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 3),
-				new BdfEntry("local", false)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 3),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		));
 
 		context.checking(new Expectations() {{
@@ -265,18 +269,18 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		Metadata meta = new Metadata();
 		// Version 3 is being delivered
 		BdfDictionary metaDictionary = BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 3),
-				new BdfEntry("local", false)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 3),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		);
 		Map<MessageId, BdfDictionary> messageMetadata =
 				new LinkedHashMap<>();
 		// A newer remote update for the same transport should not be deleted
 		MessageId fooVersion4 = new MessageId(getRandomId());
 		messageMetadata.put(fooVersion4, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 4),
-				new BdfEntry("local", false)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 4),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		));
 
 		context.checking(new Expectations() {{
@@ -342,9 +346,9 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		// A local update for another transport should be ignored
 		MessageId barUpdateId = new MessageId(getRandomId());
 		messageMetadata.put(barUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "bar"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", true)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "bar"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, true)
 		));
 
 		context.checking(new DbExpectations() {{
@@ -366,16 +370,16 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		// A local update for another transport should be ignored
 		MessageId barUpdateId = new MessageId(getRandomId());
 		messageMetadata.put(barUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "bar"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", true)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "bar"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, true)
 		));
 		// A local update for the right transport should be returned
 		MessageId fooUpdateId = new MessageId(getRandomId());
 		messageMetadata.put(fooUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", true)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, true)
 		));
 		BdfList fooUpdate = BdfList.of("foo", 1, fooPropertiesDict);
 
@@ -405,28 +409,28 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		List<Contact> contacts = asList(contact1, contact2);
 		Group contactGroup1 = getGroup(CLIENT_ID, MAJOR_VERSION);
 		Group contactGroup2 = getGroup(CLIENT_ID, MAJOR_VERSION);
-		Map<MessageId, BdfDictionary> messageMetadata2 =
+		Map<MessageId, BdfDictionary> messageMetadata =
 				new LinkedHashMap<>();
 		// A remote update for another transport should be ignored
 		MessageId barUpdateId = new MessageId(getRandomId());
-		messageMetadata2.put(barUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "bar"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", false)
+		messageMetadata.put(barUpdateId, BdfDictionary.of(
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "bar"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		));
 		// A local update for the right transport should be ignored
 		MessageId localUpdateId = new MessageId(getRandomId());
-		messageMetadata2.put(localUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", true)
+		messageMetadata.put(localUpdateId, BdfDictionary.of(
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, true)
 		));
 		// A remote update for the right transport should be returned
 		MessageId fooUpdateId = new MessageId(getRandomId());
-		messageMetadata2.put(fooUpdateId, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", false)
+		messageMetadata.put(fooUpdateId, BdfDictionary.of(
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, false)
 		));
 		BdfList fooUpdate = BdfList.of("foo", 1, fooPropertiesDict);
 
@@ -440,19 +444,25 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 			will(returnValue(contactGroup1));
 			oneOf(clientHelper).getMessageMetadataAsDictionary(txn,
 					contactGroup1.getId());
-			will(returnValue(Collections.emptyMap()));
+			will(returnValue(emptyMap()));
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup1.getId());
+			will(returnValue(new BdfDictionary()));
 			// Second contact: returns an update
 			oneOf(contactGroupFactory).createContactGroup(CLIENT_ID,
 					MAJOR_VERSION, contact2);
 			will(returnValue(contactGroup2));
 			oneOf(clientHelper).getMessageMetadataAsDictionary(txn,
 					contactGroup2.getId());
-			will(returnValue(messageMetadata2));
+			will(returnValue(messageMetadata));
 			oneOf(clientHelper).getMessageAsList(txn, fooUpdateId);
 			will(returnValue(fooUpdate));
 			oneOf(clientHelper).parseAndValidateTransportProperties(
 					fooPropertiesDict);
 			will(returnValue(fooProperties));
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup2.getId());
+			will(returnValue(new BdfDictionary()));
 		}});
 
 		TransportPropertyManagerImpl t = createInstance();
@@ -463,6 +473,62 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		assertEquals(fooProperties, properties.get(contact2.getId()));
 	}
 
+	@Test
+	public void testReceivePropertiesOverrideDiscoveredProperties()
+			throws Exception {
+		Transaction txn = new Transaction(null, true);
+		Contact contact = getContact();
+		List<Contact> contacts = singletonList(contact);
+		Group contactGroup = getGroup(CLIENT_ID, MAJOR_VERSION);
+		MessageId updateId = new MessageId(getRandomId());
+		Map<MessageId, BdfDictionary> messageMetadata = singletonMap(updateId,
+				BdfDictionary.of(
+						new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+						new BdfEntry(MSG_KEY_VERSION, 1),
+						new BdfEntry(MSG_KEY_LOCAL, false)
+				));
+		BdfList update = BdfList.of("foo", 1, fooPropertiesDict);
+		TransportProperties discovered = new TransportProperties();
+		discovered.put("fooKey1", "overridden");
+		discovered.put("fooKey3", "fooValue3");
+		BdfDictionary discoveredDict = new BdfDictionary(discovered);
+		BdfDictionary groupMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_DISCOVERED, discoveredDict)
+		);
+		TransportProperties merged = new TransportProperties();
+		merged.putAll(fooProperties);
+		merged.put("fooKey3", "fooValue3");
+
+		context.checking(new DbExpectations() {{
+			oneOf(db).transactionWithResult(with(true), withDbCallable(txn));
+			oneOf(db).getContacts(txn);
+			will(returnValue(contacts));
+			// One update
+			oneOf(contactGroupFactory).createContactGroup(CLIENT_ID,
+					MAJOR_VERSION, contact);
+			will(returnValue(contactGroup));
+			oneOf(clientHelper).getMessageMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(messageMetadata));
+			oneOf(clientHelper).getMessageAsList(txn, updateId);
+			will(returnValue(update));
+			oneOf(clientHelper).parseAndValidateTransportProperties(
+					fooPropertiesDict);
+			will(returnValue(fooProperties));
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(groupMeta));
+			oneOf(clientHelper).parseAndValidateTransportProperties(
+					discoveredDict);
+			will(returnValue(discovered));
+		}});
+
+		TransportPropertyManagerImpl t = createInstance();
+		Map<ContactId, TransportProperties> properties =
+				t.getRemoteProperties(new TransportId("foo"));
+		assertEquals(merged, properties.get(contact.getId()));
+	}
+
 	@Test
 	public void testMergingUnchangedPropertiesDoesNotCreateUpdate()
 			throws Exception {
@@ -470,9 +536,9 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		MessageId updateId = new MessageId(getRandomId());
 		Map<MessageId, BdfDictionary> messageMetadata = singletonMap(updateId,
 				BdfDictionary.of(
-						new BdfEntry("transportId", "foo"),
-						new BdfEntry("version", 1),
-						new BdfEntry("local", true)
+						new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+						new BdfEntry(MSG_KEY_VERSION, 1),
+						new BdfEntry(MSG_KEY_LOCAL, true)
 				));
 		BdfList update = BdfList.of("foo", 1, fooPropertiesDict);
 
@@ -505,7 +571,7 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 			// There are no existing properties to merge with
 			oneOf(clientHelper).getMessageMetadataAsDictionary(txn,
 					localGroup.getId());
-			will(returnValue(Collections.emptyMap()));
+			will(returnValue(emptyMap()));
 			// Store the new properties in the local group, version 1
 			expectStoreMessage(txn, localGroup.getId(), "foo",
 					fooPropertiesDict, 1, true, false);
@@ -517,7 +583,7 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 			will(returnValue(contactGroup));
 			oneOf(clientHelper).getMessageMetadataAsDictionary(txn,
 					contactGroup.getId());
-			will(returnValue(Collections.emptyMap()));
+			will(returnValue(emptyMap()));
 			expectStoreMessage(txn, contactGroup.getId(), "foo",
 					fooPropertiesDict, 1, true, true);
 		}});
@@ -532,9 +598,9 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		Contact contact = getContact();
 		Group contactGroup = getGroup(CLIENT_ID, MAJOR_VERSION);
 		BdfDictionary oldMetadata = BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 1),
-				new BdfEntry("local", true)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 1),
+				new BdfEntry(MSG_KEY_LOCAL, true)
 		);
 		MessageId localGroupUpdateId = new MessageId(getRandomId());
 		Map<MessageId, BdfDictionary> localGroupMessageMetadata =
@@ -589,14 +655,14 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		// The latest update for transport "foo" should be returned
 		MessageId fooVersion999 = new MessageId(getRandomId());
 		messageMetadata.put(fooVersion999, BdfDictionary.of(
-				new BdfEntry("transportId", "foo"),
-				new BdfEntry("version", 999)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "foo"),
+				new BdfEntry(MSG_KEY_VERSION, 999)
 		));
 		// The latest update for transport "bar" should be returned
 		MessageId barVersion3 = new MessageId(getRandomId());
 		messageMetadata.put(barVersion3, BdfDictionary.of(
-				new BdfEntry("transportId", "bar"),
-				new BdfEntry("version", 3)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, "bar"),
+				new BdfEntry(MSG_KEY_VERSION, 3)
 		));
 		BdfList fooUpdate = BdfList.of("foo", 999, fooPropertiesDict);
 		BdfList barUpdate = BdfList.of("bar", 3, barPropertiesDict);
@@ -627,9 +693,9 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		Message message = getMessage(g);
 		long timestamp = message.getTimestamp();
 		BdfDictionary meta = BdfDictionary.of(
-				new BdfEntry("transportId", transportId),
-				new BdfEntry("version", version),
-				new BdfEntry("local", local)
+				new BdfEntry(MSG_KEY_TRANSPORT_ID, transportId),
+				new BdfEntry(MSG_KEY_VERSION, version),
+				new BdfEntry(MSG_KEY_LOCAL, local)
 		);
 
 		context.checking(new Expectations() {{

bramble-core/src/test/java/org/briarproject/bramble/test/TestDuplexTransportConnection.java

@@ -4,6 +4,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
+import org.briarproject.bramble.api.properties.TransportProperties;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -37,6 +38,11 @@ public class TestDuplexTransportConnection
 		return writer;
 	}
 
+	@Override
+	public TransportProperties getRemoteProperties() {
+		return new TransportProperties();
+	}
+
 	/**
 	 * Creates and returns a pair of TestDuplexTransportConnections that are
 	 * connected to each other.