Merge branch '1832-mirror-remote-self-destruct-timer' into '804-self-destructing-messages'

Mirror the contact's changes to the self-destruct timer

See merge request briar/briar!1312

briar-android/src/main/java/org/briarproject/briar/android/conversation/ConversationViewModel.java

@@ -297,7 +297,8 @@ public class ConversationViewModel extends AndroidViewModel
 				return privateMessageFactory.createPrivateMessage(groupId,
 						timestamp, text, headers);
 			} else {
-				long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+				long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+						timestamp);
 				return privateMessageFactory.createPrivateMessage(groupId,
 						timestamp, text, headers, timer);
 			}

briar-android/src/main/java/org/briarproject/briar/android/privategroup/creation/CreateGroupControllerImpl.java

@@ -171,7 +171,8 @@ class CreateGroupControllerImpl extends ContactSelectorControllerImpl
 				Contact contact = contactManager.getContact(txn, c);
 				long timestamp = conversationManager
 						.getTimestampForOutgoingMessage(txn, c);
-				long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+				long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+						timestamp);
 				contexts.add(new InvitationContext(contact, timestamp, timer));
 			} catch (NoSuchContactException e) {
 				// Continue

briar-api/src/main/java/org/briarproject/briar/api/autodelete/AutoDeleteManager.java

@@ -24,8 +24,33 @@ public interface AutoDeleteManager {
 	 */
 	int MINOR_VERSION = 0;
 
+	/**
+	 * Returns the auto-delete timer duration for the given contact. Use
+	 * {@link #getAutoDeleteTimer(Transaction, ContactId, long)} if the timer
+	 * will be used in an outgoing message.
+	 */
 	long getAutoDeleteTimer(Transaction txn, ContactId c) throws DbException;
 
+	/**
+	 * Returns the auto-delete timer duration for the given contact, for use in
+	 * a message with the given timestamp. The timestamp is stored.
+	 */
+	long getAutoDeleteTimer(Transaction txn, ContactId c, long timestamp)
+			throws DbException;
+
+	/**
+	 * Sets the auto-delete timer duration for the given contact.
+	 */
 	void setAutoDeleteTimer(Transaction txn, ContactId c, long timer)
 			throws DbException;
+
+	/**
+	 * Receives an auto-delete timer duration from the given contact, carried
+	 * in a message with the given timestamp. The local timer is set to the
+	 * same duration unless it has been
+	 * {@link #setAutoDeleteTimer(Transaction, ContactId, long) changed} more
+	 * recently than the remote timer.
+	 */
+	void receiveAutoDeleteTimer(Transaction txn, ContactId c, long timer,
+			long timestamp) throws DbException;
 }

briar-core/src/main/java/org/briarproject/briar/autodelete/AutoDeleteConstants.java

@@ -2,6 +2,28 @@ package org.briarproject.briar.autodelete;
 
 interface AutoDeleteConstants {
 
-	// Group metadata key for storing the auto-delete timer
-	String GROUP_KEY_AUTO_DELETE_TIMER = "autoDeleteTimer";
+	/**
+	 * Group metadata key for storing the auto-delete timer duration.
+	 */
+	String GROUP_KEY_TIMER = "autoDeleteTimer";
+
+	/**
+	 * Group metadata key for storing the timestamp of the latest incoming or
+	 * outgoing message carrying an auto-delete timer (including a null timer).
+	 */
+	String GROUP_KEY_TIMESTAMP = "autoDeleteTimestamp";
+
+	/**
+	 * Group metadata key for storing the previous auto-delete timer duration.
+	 * This is used to decide whether a local change to the duration should be
+	 * overwritten by a duration received from the contact.
+	 */
+	String GROUP_KEY_PREVIOUS_TIMER = "autoDeletePreviousTimer";
+
+	/**
+	 * Special value for {@link #GROUP_KEY_PREVIOUS_TIMER} indicating that
+	 * there are no local changes to the auto-delete timer duration that need
+	 * to be compared with durations received from the contact.
+	 */
+	long NO_PREVIOUS_TIMER = 0;
 }

briar-core/src/main/java/org/briarproject/briar/autodelete/AutoDeleteManagerImpl.java

@@ -17,19 +17,29 @@ import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.GroupFactory;
 import org.briarproject.briar.api.autodelete.AutoDeleteManager;
 
+import java.util.logging.Logger;
+
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
+import static java.util.logging.Level.INFO;
+import static java.util.logging.Logger.getLogger;
 import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.MAX_AUTO_DELETE_TIMER_MS;
 import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.MIN_AUTO_DELETE_TIMER_MS;
 import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.NO_AUTO_DELETE_TIMER;
-import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_AUTO_DELETE_TIMER;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_PREVIOUS_TIMER;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_TIMER;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_TIMESTAMP;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.NO_PREVIOUS_TIMER;
 
 @Immutable
 @NotNullByDefault
 class AutoDeleteManagerImpl
 		implements AutoDeleteManager, OpenDatabaseHook, ContactHook {
 
+	private static final Logger LOG =
+			getLogger(AutoDeleteManagerImpl.class.getName());
+
 	private final DatabaseComponent db;
 	private final ClientHelper clientHelper;
 	private final GroupFactory groupFactory;
@@ -75,8 +85,29 @@ class AutoDeleteManagerImpl
 			Group g = getGroup(db.getContact(txn, c));
 			BdfDictionary meta =
 					clientHelper.getGroupMetadataAsDictionary(txn, g.getId());
-			return meta.getLong(GROUP_KEY_AUTO_DELETE_TIMER,
-					NO_AUTO_DELETE_TIMER);
+			return meta.getLong(GROUP_KEY_TIMER, NO_AUTO_DELETE_TIMER);
+		} catch (FormatException e) {
+			throw new DbException(e);
+		}
+	}
+
+	@Override
+	public long getAutoDeleteTimer(Transaction txn, ContactId c, long timestamp)
+			throws DbException {
+		try {
+			Group g = getGroup(db.getContact(txn, c));
+			BdfDictionary meta =
+					clientHelper.getGroupMetadataAsDictionary(txn, g.getId());
+			long timer = meta.getLong(GROUP_KEY_TIMER, NO_AUTO_DELETE_TIMER);
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Sending message with auto-delete timer " + timer);
+			}
+			// Update the timestamp and clear the previous timer, if any
+			meta = BdfDictionary.of(
+					new BdfEntry(GROUP_KEY_TIMESTAMP, timestamp),
+					new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER));
+			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
+			return timer;
 		} catch (FormatException e) {
 			throw new DbException(e);
 		}
@@ -85,18 +116,60 @@ class AutoDeleteManagerImpl
 	@Override
 	public void setAutoDeleteTimer(Transaction txn, ContactId c, long timer)
 			throws DbException {
-		if (timer != NO_AUTO_DELETE_TIMER &&
-				(timer < MIN_AUTO_DELETE_TIMER_MS ||
-						timer > MAX_AUTO_DELETE_TIMER_MS)) {
-			throw new IllegalArgumentException();
-		}
+		validateTimer(timer);
 		try {
 			Group g = getGroup(db.getContact(txn, c));
-			BdfDictionary meta = BdfDictionary.of(
-					new BdfEntry(GROUP_KEY_AUTO_DELETE_TIMER, timer));
+			BdfDictionary meta =
+					clientHelper.getGroupMetadataAsDictionary(txn, g.getId());
+			long oldTimer = meta.getLong(GROUP_KEY_TIMER, NO_AUTO_DELETE_TIMER);
+			if (timer == oldTimer) return;
+			if (LOG.isLoggable(INFO)) {
+				LOG.info("Setting auto-delete timer to " + timer);
+			}
+			// Store the new timer and the previous timer
+			meta = BdfDictionary.of(
+					new BdfEntry(GROUP_KEY_TIMER, timer),
+					new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, oldTimer));
 			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
 		} catch (FormatException e) {
-			throw new AssertionError(e);
+			throw new DbException(e);
+		}
+	}
+
+	@Override
+	public void receiveAutoDeleteTimer(Transaction txn, ContactId c,
+			long timer, long timestamp) throws DbException {
+		validateTimer(timer);
+		try {
+			Group g = getGroup(db.getContact(txn, c));
+			BdfDictionary meta =
+					clientHelper.getGroupMetadataAsDictionary(txn, g.getId());
+			long oldTimestamp = meta.getLong(GROUP_KEY_TIMESTAMP, 0L);
+			if (timestamp <= oldTimestamp) return;
+			long oldTimer =
+					meta.getLong(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER);
+			meta = new BdfDictionary();
+			if (oldTimer == NO_PREVIOUS_TIMER) {
+				// We don't have an unsent change. Mirror their timer
+				if (LOG.isLoggable(INFO)) {
+					LOG.info("Mirroring auto-delete timer " + timer);
+				}
+				meta.put(GROUP_KEY_TIMER, timer);
+			} else if (timer != oldTimer) {
+				// Their sent change trumps our unsent change. Mirror their
+				// timer and clear the previous timer to drop our unsent change
+				if (LOG.isLoggable(INFO)) {
+					LOG.info("Mirroring auto-delete timer " + timer
+							+ " and forgetting unsent change");
+				}
+				meta.put(GROUP_KEY_TIMER, timer);
+				meta.put(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER);
+			}
+			// Always update the timestamp
+			meta.put(GROUP_KEY_TIMESTAMP, timestamp);
+			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
+		} catch (FormatException e) {
+			throw new DbException(e);
 		}
 	}
 
@@ -104,4 +177,12 @@ class AutoDeleteManagerImpl
 		byte[] descriptor = c.getAuthor().getId().getBytes();
 		return groupFactory.createGroup(CLIENT_ID, MAJOR_VERSION, descriptor);
 	}
+
+	private void validateTimer(long timer) {
+		if (timer != NO_AUTO_DELETE_TIMER &&
+				(timer < MIN_AUTO_DELETE_TIMER_MS ||
+						timer > MAX_AUTO_DELETE_TIMER_MS)) {
+			throw new IllegalArgumentException();
+		}
+	}
 }

briar-core/src/main/java/org/briarproject/briar/introduction/AbstractProtocolEngine.java

@@ -96,7 +96,8 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		Message m;
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
-			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+					timestamp);
 			m = messageEncoder.encodeRequestMessage(s.getContactGroupId(),
 					timestamp, s.getLastLocalMessageId(), author, text, timer);
 			sendMessage(txn, REQUEST, s.getSessionId(), m, true, timer);
@@ -116,7 +117,8 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		Message m;
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
-			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+					timestamp);
 			m = messageEncoder.encodeAcceptMessage(s.getContactGroupId(),
 					timestamp, s.getLastLocalMessageId(), s.getSessionId(),
 					ephemeralPublicKey, acceptTimestamp, transportProperties,
@@ -137,7 +139,8 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		Message m;
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
-			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+					timestamp);
 			m = messageEncoder.encodeDeclineMessage(s.getContactGroupId(),
 					timestamp, s.getLastLocalMessageId(), s.getSessionId(),
 					timer);
@@ -237,6 +240,13 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		return conversationManager.getTimestampForOutgoingMessage(txn, c);
 	}
 
+	void receiveAutoDeleteTimer(Transaction txn, AbstractIntroductionMessage m)
+			throws DbException {
+		ContactId c = getContactId(txn, m.getGroupId());
+		autoDeleteManager.receiveAutoDeleteTimer(txn, c, m.getAutoDeleteTimer(),
+				m.getTimestamp());
+	}
+
 	private ContactId getContactId(Transaction txn, GroupId contactGroupId)
 			throws DbException {
 		try {

briar-core/src/main/java/org/briarproject/briar/introduction/IntroduceeProtocolEngine.java

@@ -257,6 +257,9 @@ class IntroduceeProtocolEngine
 		messageTracker
 				.trackMessage(txn, m.getGroupId(), m.getTimestamp(), false);
 
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
+
 		// Broadcast IntroductionRequestReceivedEvent
 		LocalAuthor localAuthor = identityManager.getLocalAuthor(txn);
 		Contact c = contactManager.getContact(txn, s.getIntroducer().getId(),
@@ -332,8 +335,7 @@ class IntroduceeProtocolEngine
 	}
 
 	private IntroduceeSession onRemoteAccept(Transaction txn,
-			IntroduceeSession s, AcceptMessage m)
-			throws DbException {
+			IntroduceeSession s, AcceptMessage m) throws DbException {
 		// The timestamp must be higher than the last request message
 		if (m.getTimestamp() <= s.getRequestTimestamp())
 			return abort(txn, s);
@@ -370,6 +372,9 @@ class IntroduceeProtocolEngine
 		messageTracker
 				.trackMessage(txn, m.getGroupId(), m.getTimestamp(), false);
 
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
+
 		// Broadcast IntroductionResponseReceivedEvent
 		broadcastIntroductionResponseReceivedEvent(txn, s,
 				s.getIntroducer().getId(), s.getRemote().author, m, false);

briar-core/src/main/java/org/briarproject/briar/introduction/IntroducerProtocolEngine.java

@@ -260,6 +260,8 @@ class IntroducerProtocolEngine
 		// Track the incoming message
 		messageTracker
 				.trackMessage(txn, m.getGroupId(), m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 
 		// Forward ACCEPT message
 		Introducee i = getOtherIntroducee(s, m.getGroupId());
@@ -321,6 +323,8 @@ class IntroducerProtocolEngine
 		// Track the incoming message
 		messageTracker
 				.trackMessage(txn, m.getGroupId(), m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 
 		// Forward ACCEPT message
 		Introducee i = getOtherIntroducee(s, m.getGroupId());
@@ -374,6 +378,8 @@ class IntroducerProtocolEngine
 		// Track the incoming message
 		messageTracker
 				.trackMessage(txn, m.getGroupId(), m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 
 		// Forward DECLINE message
 		Introducee i = getOtherIntroducee(s, m.getGroupId());
@@ -427,6 +433,8 @@ class IntroducerProtocolEngine
 		// Track the incoming message
 		messageTracker
 				.trackMessage(txn, m.getGroupId(), m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 
 		// Forward DECLINE message
 		Introducee i = getOtherIntroducee(s, m.getGroupId());

briar-core/src/main/java/org/briarproject/briar/messaging/MessagingManagerImpl.java

@@ -27,6 +27,7 @@ import org.briarproject.bramble.api.sync.MessageStatus;
 import org.briarproject.bramble.api.sync.validation.IncomingMessageHook;
 import org.briarproject.bramble.api.versioning.ClientVersioningManager;
 import org.briarproject.bramble.api.versioning.ClientVersioningManager.ClientVersioningHook;
+import org.briarproject.briar.api.autodelete.AutoDeleteManager;
 import org.briarproject.briar.api.client.MessageTracker;
 import org.briarproject.briar.api.client.MessageTracker.GroupCount;
 import org.briarproject.briar.api.conversation.ConversationManager.ConversationClient;
@@ -89,18 +90,24 @@ class MessagingManagerImpl implements MessagingManager, IncomingMessageHook,
 	private final MessageTracker messageTracker;
 	private final ClientVersioningManager clientVersioningManager;
 	private final ContactGroupFactory contactGroupFactory;
+	private final AutoDeleteManager autoDeleteManager;
 
 	@Inject
-	MessagingManagerImpl(DatabaseComponent db, ClientHelper clientHelper,
+	MessagingManagerImpl(
+			DatabaseComponent db,
+			ClientHelper clientHelper,
 			ClientVersioningManager clientVersioningManager,
-			MetadataParser metadataParser, MessageTracker messageTracker,
-			ContactGroupFactory contactGroupFactory) {
+			MetadataParser metadataParser,
+			MessageTracker messageTracker,
+			ContactGroupFactory contactGroupFactory,
+			AutoDeleteManager autoDeleteManager) {
 		this.db = db;
 		this.clientHelper = clientHelper;
 		this.metadataParser = metadataParser;
 		this.messageTracker = messageTracker;
 		this.clientVersioningManager = clientVersioningManager;
 		this.contactGroupFactory = contactGroupFactory;
+		this.autoDeleteManager = autoDeleteManager;
 	}
 
 	@Override
@@ -205,6 +212,8 @@ class MessagingManagerImpl implements MessagingManager, IncomingMessageHook,
 				new PrivateMessageReceivedEvent(header, contactId);
 		txn.attach(event);
 		messageTracker.trackIncomingMessage(txn, m);
+		autoDeleteManager.receiveAutoDeleteTimer(txn, contactId, timer,
+				timestamp);
 	}
 
 	private List<AttachmentHeader> parseAttachmentHeaders(BdfDictionary meta)

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/AbstractProtocolEngine.java

@@ -152,9 +152,11 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
 			// Set auto-delete timer if manually accepting an invitation
-			long timer = visibleInUi
-					? autoDeleteManager.getAutoDeleteTimer(txn, c)
-					: NO_AUTO_DELETE_TIMER;
+			long timer = NO_AUTO_DELETE_TIMER;
+			if (visibleInUi) {
+				timer = autoDeleteManager
+						.getAutoDeleteTimer(txn, c, localTimestamp);
+			}
 			m = messageEncoder.encodeJoinMessage(s.getContactGroupId(),
 					s.getPrivateGroupId(), localTimestamp,
 					s.getLastLocalMessageId(), timer);
@@ -179,9 +181,11 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
 			// Set auto-delete timer if manually accepting an invitation
-			long timer = visibleInUi
-					? autoDeleteManager.getAutoDeleteTimer(txn, c)
-					: NO_AUTO_DELETE_TIMER;
+			long timer = NO_AUTO_DELETE_TIMER;
+			if (visibleInUi) {
+				timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+						localTimestamp);
+			}
 			m = messageEncoder.encodeLeaveMessage(s.getContactGroupId(),
 					s.getPrivateGroupId(), localTimestamp,
 					s.getLastLocalMessageId(), timer);
@@ -296,6 +300,13 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		return max(s.getLocalTimestamp(), s.getInviteTimestamp());
 	}
 
+	void receiveAutoDeleteTimer(Transaction txn,
+			DeletableGroupInvitationMessage m) throws DbException {
+		ContactId c = getContactId(txn, m.getContactGroupId());
+		autoDeleteManager.receiveAutoDeleteTimer(txn, c, m.getAutoDeleteTimer(),
+				m.getTimestamp());
+	}
+
 	private void sendMessage(Transaction txn, Message m, MessageType type,
 			GroupId privateGroupId, boolean visibleInConversation,
 			long autoDeleteTimer) throws DbException {

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/CreatorProtocolEngine.java

@@ -201,6 +201,8 @@ class CreatorProtocolEngine extends AbstractProtocolEngine<CreatorSession> {
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Share the private group with the contact
 		setPrivateGroupVisibility(txn, s, SHARED);
 		// Broadcast an event
@@ -226,6 +228,8 @@ class CreatorProtocolEngine extends AbstractProtocolEngine<CreatorSession> {
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Broadcast an event
 		ContactId contactId =
 				clientHelper.getContactId(txn, m.getContactGroupId());

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/InviteeProtocolEngine.java

@@ -251,6 +251,8 @@ class InviteeProtocolEngine extends AbstractProtocolEngine<InviteeSession> {
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Broadcast an event
 		PrivateGroup privateGroup = privateGroupFactory.createPrivateGroup(
 				m.getGroupName(), m.getCreator(), m.getSalt());

briar-core/src/main/java/org/briarproject/briar/sharing/ProtocolEngineImpl.java

@@ -142,7 +142,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		long localTimestamp = getTimestampForVisibleMessage(txn, s);
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
-			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+					localTimestamp);
 			m = messageEncoder.encodeInviteMessage(s.getContactGroupId(),
 					localTimestamp, s.getLastLocalMessageId(), descriptor,
 					text, timer);
@@ -209,7 +210,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		long localTimestamp = getTimestampForVisibleMessage(txn, s);
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
-			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+					localTimestamp);
 			m = messageEncoder.encodeAcceptMessage(s.getContactGroupId(),
 					s.getShareableId(), localTimestamp,
 					s.getLastLocalMessageId(), timer);
@@ -263,7 +265,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		long localTimestamp = getTimestampForVisibleMessage(txn, s);
 		ContactId c = getContactId(txn, s.getContactGroupId());
 		if (contactSupportsAutoDeletion(txn, c)) {
-			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c);
+			long timer = autoDeleteManager.getAutoDeleteTimer(txn, c,
+					localTimestamp);
 			m = messageEncoder.encodeDeclineMessage(s.getContactGroupId(),
 					s.getShareableId(), localTimestamp,
 					s.getLastLocalMessageId(), timer);
@@ -357,6 +360,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Broadcast an event
 		ContactId contactId =
 				clientHelper.getContactId(txn, s.getContactGroupId());
@@ -382,6 +387,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Share the shareable with the contact
 		setShareableVisibility(txn, s, SHARED);
 		// Broadcast an event
@@ -429,6 +436,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Broadcast an event
 		ContactId contactId =
 				clientHelper.getContactId(txn, m.getContactGroupId());
@@ -482,6 +491,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		// Track the message
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
+		// Receive the auto-delete timer
+		receiveAutoDeleteTimer(txn, m);
 		// Make the shareable invisible (not actually needed in REMOTE_HANGING)
 		try {
 			setShareableVisibility(txn, s, INVISIBLE);
@@ -716,6 +727,13 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		return max(s.getLocalTimestamp(), s.getInviteTimestamp());
 	}
 
+	private void receiveAutoDeleteTimer(Transaction txn,
+			DeletableSharingMessage m) throws DbException {
+		ContactId c = getContactId(txn, m.getContactGroupId());
+		autoDeleteManager.receiveAutoDeleteTimer(txn, c, m.getAutoDeleteTimer(),
+				m.getTimestamp());
+	}
+
 	private ContactId getContactId(Transaction txn, GroupId contactGroupId)
 			throws DbException {
 		try {

briar-core/src/test/java/org/briarproject/briar/autodelete/AutoDeleteManagerImplTest.java

@@ -18,12 +18,17 @@ import static org.briarproject.bramble.api.client.ContactGroupConstants.GROUP_KE
 import static org.briarproject.bramble.test.TestUtils.getContact;
 import static org.briarproject.bramble.test.TestUtils.getGroup;
 import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.MAX_AUTO_DELETE_TIMER_MS;
+import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.MIN_AUTO_DELETE_TIMER_MS;
 import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.NO_AUTO_DELETE_TIMER;
 import static org.briarproject.briar.api.autodelete.AutoDeleteManager.CLIENT_ID;
 import static org.briarproject.briar.api.autodelete.AutoDeleteManager.MAJOR_VERSION;
-import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_AUTO_DELETE_TIMER;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_PREVIOUS_TIMER;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_TIMER;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.GROUP_KEY_TIMESTAMP;
+import static org.briarproject.briar.autodelete.AutoDeleteConstants.NO_PREVIOUS_TIMER;
 import static org.junit.Assert.assertEquals;
 
+@SuppressWarnings("UnnecessaryLocalVariable") // Using them for readability
 public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 
 	private final DatabaseComponent db = context.mock(DatabaseComponent.class);
@@ -35,6 +40,7 @@ public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 	private final Group localGroup = getGroup(CLIENT_ID, MAJOR_VERSION);
 	private final Group contactGroup = getGroup(CLIENT_ID, MAJOR_VERSION);
 	private final Contact contact = getContact();
+	private final long now = System.currentTimeMillis();
 
 	private final AutoDeleteManagerImpl autoDeleteManager;
 
@@ -113,15 +119,44 @@ public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 	@Test
 	public void testStoresTimer() throws Exception {
 		Transaction txn = new Transaction(null, false);
-		long timer = MAX_AUTO_DELETE_TIMER_MS;
-		BdfDictionary meta = BdfDictionary.of(
-				new BdfEntry(GROUP_KEY_AUTO_DELETE_TIMER, timer));
+		long oldTimer = MIN_AUTO_DELETE_TIMER_MS;
+		long newTimer = MAX_AUTO_DELETE_TIMER_MS;
+		BdfDictionary oldMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, oldTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER),
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now));
+		BdfDictionary newMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, newTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, oldTimer));
 
 		expectGetContact(txn);
 		expectGetContactGroup();
 		context.checking(new Expectations() {{
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(oldMeta));
 			oneOf(clientHelper).mergeGroupMetadata(txn,
-					contactGroup.getId(), meta);
+					contactGroup.getId(), newMeta);
+		}});
+
+		autoDeleteManager.setAutoDeleteTimer(txn, contact.getId(), newTimer);
+	}
+
+	@Test
+	public void testDoesNotStoreTimerIfUnchanged() throws Exception {
+		Transaction txn = new Transaction(null, false);
+		long timer = MAX_AUTO_DELETE_TIMER_MS;
+		BdfDictionary meta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, timer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER),
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now));
+
+		expectGetContact(txn);
+		expectGetContactGroup();
+		context.checking(new Expectations() {{
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(meta));
 		}});
 
 		autoDeleteManager.setAutoDeleteTimer(txn, contact.getId(), timer);
@@ -133,7 +168,10 @@ public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 		long timer = MAX_AUTO_DELETE_TIMER_MS;
 		BdfDictionary meta = BdfDictionary.of(
 				new BdfEntry(GROUP_KEY_CONTACT_ID, contact.getId().getInt()),
-				new BdfEntry(GROUP_KEY_AUTO_DELETE_TIMER, timer));
+				new BdfEntry(GROUP_KEY_TIMER, timer));
+		BdfDictionary newMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER));
 
 		expectGetContact(txn);
 		expectGetContactGroup();
@@ -141,10 +179,12 @@ public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
 					contactGroup.getId());
 			will(returnValue(meta));
+			oneOf(clientHelper).mergeGroupMetadata(txn, contactGroup.getId(),
+					newMeta);
 		}});
 
-		assertEquals(timer,
-				autoDeleteManager.getAutoDeleteTimer(txn, contact.getId()));
+		assertEquals(timer, autoDeleteManager
+				.getAutoDeleteTimer(txn, contact.getId(), now));
 	}
 
 	@Test
@@ -152,6 +192,44 @@ public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 		Transaction txn = new Transaction(null, false);
 		BdfDictionary meta = BdfDictionary.of(
 				new BdfEntry(GROUP_KEY_CONTACT_ID, contact.getId().getInt()));
+		BdfDictionary newMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER));
+
+		expectGetContact(txn);
+		expectGetContactGroup();
+		context.checking(new Expectations() {{
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(meta));
+			oneOf(clientHelper).mergeGroupMetadata(txn, contactGroup.getId(),
+					newMeta);
+		}});
+
+		assertEquals(NO_AUTO_DELETE_TIMER, autoDeleteManager
+				.getAutoDeleteTimer(txn, contact.getId(), now));
+	}
+
+	@Test
+	public void testIgnoresReceivedTimerWithEarlierTimestamp()
+			throws Exception {
+		testIgnoresReceivedTimerWithTimestamp(now - 1);
+	}
+
+	@Test
+	public void testIgnoresReceivedTimerWithEqualTimestamp() throws Exception {
+		testIgnoresReceivedTimerWithTimestamp(now);
+	}
+
+	private void testIgnoresReceivedTimerWithTimestamp(long remoteTimestamp)
+			throws Exception {
+		Transaction txn = new Transaction(null, false);
+		long localTimer = MIN_AUTO_DELETE_TIMER_MS;
+		long remoteTimer = MAX_AUTO_DELETE_TIMER_MS;
+		BdfDictionary meta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, localTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER),
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now));
 
 		expectGetContact(txn);
 		expectGetContactGroup();
@@ -161,8 +239,99 @@ public class AutoDeleteManagerImplTest extends BrambleMockTestCase {
 			will(returnValue(meta));
 		}});
 
-		assertEquals(NO_AUTO_DELETE_TIMER,
-				autoDeleteManager.getAutoDeleteTimer(txn, contact.getId()));
+		autoDeleteManager.receiveAutoDeleteTimer(txn, contact.getId(),
+				remoteTimer, remoteTimestamp);
+	}
+
+	@Test
+	public void testMirrorsRemoteTimestampIfNoUnsentChange() throws Exception {
+		Transaction txn = new Transaction(null, false);
+		long localTimer = MIN_AUTO_DELETE_TIMER_MS;
+		long remoteTimer = MAX_AUTO_DELETE_TIMER_MS;
+		long remoteTimestamp = now + 1;
+		BdfDictionary oldMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, localTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER),
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now));
+		// The timestamp should be updated and the timer should be mirrored
+		BdfDictionary newMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMESTAMP, remoteTimestamp),
+				new BdfEntry(GROUP_KEY_TIMER, remoteTimer));
+
+		expectGetContact(txn);
+		expectGetContactGroup();
+		context.checking(new Expectations() {{
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(oldMeta));
+			oneOf(clientHelper).mergeGroupMetadata(txn,
+					contactGroup.getId(), newMeta);
+		}});
+
+		autoDeleteManager.receiveAutoDeleteTimer(txn, contact.getId(),
+				remoteTimer, remoteTimestamp);
+	}
+
+	@Test
+	public void testDoesNotMirrorUnchangedRemoteTimestampIfUnsentChange()
+			throws Exception {
+		Transaction txn = new Transaction(null, false);
+		long localTimer = MIN_AUTO_DELETE_TIMER_MS;
+		long remoteTimer = MAX_AUTO_DELETE_TIMER_MS;
+		long remoteTimestamp = now + 1;
+		BdfDictionary oldMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, localTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, remoteTimer),
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now));
+		// The timestamp should be updated but the timer should not revert
+		BdfDictionary newMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMESTAMP, remoteTimestamp));
+
+		expectGetContact(txn);
+		expectGetContactGroup();
+		context.checking(new Expectations() {{
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(oldMeta));
+			oneOf(clientHelper).mergeGroupMetadata(txn,
+					contactGroup.getId(), newMeta);
+		}});
+
+		autoDeleteManager.receiveAutoDeleteTimer(txn, contact.getId(),
+				remoteTimer, remoteTimestamp);
+	}
+
+	@Test
+	public void testMirrorsChangedRemoteTimestampIfUnsentChange()
+			throws Exception {
+		Transaction txn = new Transaction(null, false);
+		long localTimer = MIN_AUTO_DELETE_TIMER_MS;
+		long oldRemoteTimer = MAX_AUTO_DELETE_TIMER_MS;
+		long newRemoteTimer = MAX_AUTO_DELETE_TIMER_MS - 1;
+		long remoteTimestamp = now + 1;
+		BdfDictionary oldMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMER, localTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, oldRemoteTimer),
+				new BdfEntry(GROUP_KEY_TIMESTAMP, now));
+		// The timestamp should be updated , the timer should be mirrored and
+		// the previous timer should be cleared
+		BdfDictionary newMeta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_TIMESTAMP, remoteTimestamp),
+				new BdfEntry(GROUP_KEY_TIMER, newRemoteTimer),
+				new BdfEntry(GROUP_KEY_PREVIOUS_TIMER, NO_PREVIOUS_TIMER));
+
+		expectGetContact(txn);
+		expectGetContactGroup();
+		context.checking(new Expectations() {{
+			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+					contactGroup.getId());
+			will(returnValue(oldMeta));
+			oneOf(clientHelper).mergeGroupMetadata(txn,
+					contactGroup.getId(), newMeta);
+		}});
+
+		autoDeleteManager.receiveAutoDeleteTimer(txn, contact.getId(),
+				newRemoteTimer, remoteTimestamp);
 	}
 
 	private void expectGetContact(Transaction txn) throws Exception {

briar-core/src/test/java/org/briarproject/briar/blog/BlogManagerIntegrationTest.java

@@ -46,8 +46,6 @@ public class BlogManagerIntegrationTest
 	public void setUp() throws Exception {
 		super.setUp();
 
-		author0 = identityManager0.getLocalAuthor();
-		author1 = identityManager1.getLocalAuthor();
 		String rssTitle = getRandomString(MAX_AUTHOR_NAME_LENGTH);
 		rssAuthor = c0.getAuthorFactory().createLocalAuthor(rssTitle);
 

briar-core/src/test/java/org/briarproject/briar/introduction/IntroductionIntegrationTest.java

@@ -263,8 +263,8 @@ public class IntroductionIntegrationTest
 		addListeners(true, true);
 
 		// 0 and 1 set an auto-delete timer for their conversation
-		setAutoDeleteTimer(c0, contactId1From0);
-		setAutoDeleteTimer(c1, contactId0From1);
+		setAutoDeleteTimer(c0, contactId1From0, MIN_AUTO_DELETE_TIMER_MS);
+		setAutoDeleteTimer(c1, contactId0From1, MIN_AUTO_DELETE_TIMER_MS);
 
 		// Make introduction
 		introductionManager0

briar-core/src/test/java/org/briarproject/briar/messaging/AutoDeleteIntegrationTest.java

@@ -0,0 +1,241 @@
+package org.briarproject.briar.messaging;
+
+import org.briarproject.bramble.api.contact.ContactId;
+import org.briarproject.bramble.api.db.DatabaseComponent;
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.sync.GroupId;
+import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.bramble.test.TestDatabaseConfigModule;
+import org.briarproject.briar.api.autodelete.AutoDeleteManager;
+import org.briarproject.briar.api.conversation.ConversationManager;
+import org.briarproject.briar.api.conversation.ConversationMessageHeader;
+import org.briarproject.briar.api.messaging.MessagingManager;
+import org.briarproject.briar.api.messaging.PrivateMessage;
+import org.briarproject.briar.api.messaging.PrivateMessageFactory;
+import org.briarproject.briar.test.BriarIntegrationTest;
+import org.briarproject.briar.test.BriarIntegrationTestComponent;
+import org.briarproject.briar.test.DaggerBriarIntegrationTestComponent;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import static java.util.Collections.emptyList;
+import static java.util.Collections.sort;
+import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.MIN_AUTO_DELETE_TIMER_MS;
+import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.NO_AUTO_DELETE_TIMER;
+import static org.junit.Assert.assertEquals;
+
+public class AutoDeleteIntegrationTest
+		extends BriarIntegrationTest<BriarIntegrationTestComponent> {
+
+	@Override
+	protected void createComponents() {
+		BriarIntegrationTestComponent component =
+				DaggerBriarIntegrationTestComponent.builder().build();
+		BriarIntegrationTestComponent.Helper.injectEagerSingletons(component);
+		component.inject(this);
+
+		c0 = DaggerBriarIntegrationTestComponent.builder()
+				.testDatabaseConfigModule(new TestDatabaseConfigModule(t0Dir))
+				.build();
+		BriarIntegrationTestComponent.Helper.injectEagerSingletons(c0);
+
+		c1 = DaggerBriarIntegrationTestComponent.builder()
+				.testDatabaseConfigModule(new TestDatabaseConfigModule(t1Dir))
+				.build();
+		BriarIntegrationTestComponent.Helper.injectEagerSingletons(c1);
+
+		c2 = DaggerBriarIntegrationTestComponent.builder()
+				.testDatabaseConfigModule(new TestDatabaseConfigModule(t2Dir))
+				.build();
+		BriarIntegrationTestComponent.Helper.injectEagerSingletons(c2);
+	}
+
+	@Test
+	public void testMessageWithoutTimer() throws Exception {
+		// 0 creates a message without a timer
+		MessageId messageId = createMessageWithoutTimer(c0, contactId1From0);
+		// The message should have been added to 0's view of the conversation
+		List<ConversationMessageHeader> headers0 =
+				getMessageHeaders(c0, contactId1From0);
+		assertEquals(1, headers0.size());
+		ConversationMessageHeader h0 = headers0.get(0);
+		assertEquals(messageId, h0.getId());
+		// The message should not have a timer
+		assertEquals(NO_AUTO_DELETE_TIMER, h0.getAutoDeleteTimer());
+		// Sync the message to 1
+		sync0To1(1, true);
+		// The message should have been added to 1's view of the conversation
+		List<ConversationMessageHeader> headers1 =
+				getMessageHeaders(c1, contactId0From1);
+		assertEquals(1, headers1.size());
+		ConversationMessageHeader h1 = headers1.get(0);
+		assertEquals(messageId, h1.getId());
+		// The message should not have a timer
+		assertEquals(NO_AUTO_DELETE_TIMER, h1.getAutoDeleteTimer());
+	}
+
+	@Test
+	public void testDefaultTimer() throws Exception {
+		// 0 creates a message with the default timer
+		MessageId messageId = createMessageWithTimer(c0, contactId1From0);
+		// The message should have been added to 0's view of the conversation
+		List<ConversationMessageHeader> headers0 =
+				getMessageHeaders(c0, contactId1From0);
+		assertEquals(1, headers0.size());
+		ConversationMessageHeader h0 = headers0.get(0);
+		assertEquals(messageId, h0.getId());
+		// The message should have the default timer (none)
+		assertEquals(NO_AUTO_DELETE_TIMER, h0.getAutoDeleteTimer());
+		// Sync the message to 1
+		sync0To1(1, true);
+		// The message should have been added to 1's view of the conversation
+		List<ConversationMessageHeader> headers1 =
+				getMessageHeaders(c1, contactId0From1);
+		assertEquals(1, headers1.size());
+		ConversationMessageHeader h1 = headers1.get(0);
+		assertEquals(messageId, h1.getId());
+		// The message should have the default timer (none)
+		assertEquals(NO_AUTO_DELETE_TIMER, h1.getAutoDeleteTimer());
+		// Both peers should still be using the default timer
+		assertEquals(NO_AUTO_DELETE_TIMER,
+				getAutoDeleteTimer(c0, contactId1From0));
+		assertEquals(NO_AUTO_DELETE_TIMER,
+				getAutoDeleteTimer(c1, contactId0From1));
+	}
+
+	@Test
+	public void testTimerIsMirrored() throws Exception {
+		// Set 0's timer
+		setAutoDeleteTimer(c0, contactId1From0, MIN_AUTO_DELETE_TIMER_MS);
+		// 0 should be using the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				getAutoDeleteTimer(c0, contactId1From0));
+		// 1 should still be using the default timer
+		assertEquals(NO_AUTO_DELETE_TIMER,
+				getAutoDeleteTimer(c1, contactId0From1));
+		// 0 creates a message with the new timer
+		MessageId messageId0 = createMessageWithTimer(c0, contactId1From0);
+		// The message should have been added to 0's view of the conversation
+		List<ConversationMessageHeader> headers0 =
+				getMessageHeaders(c0, contactId1From0);
+		assertEquals(1, headers0.size());
+		ConversationMessageHeader h0 = headers0.get(0);
+		assertEquals(messageId0, h0.getId());
+		// The message should have the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS, h0.getAutoDeleteTimer());
+		// Sync the message to 1
+		sync0To1(1, true);
+		// The message should have been added to 1's view of the conversation
+		List<ConversationMessageHeader> headers1 =
+				getMessageHeaders(c1, contactId0From1);
+		assertEquals(1, headers1.size());
+		ConversationMessageHeader h1 = headers1.get(0);
+		assertEquals(messageId0, h1.getId());
+		// The message should have the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS, h1.getAutoDeleteTimer());
+		// 0 and 1 should both be using the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				getAutoDeleteTimer(c0, contactId1From0));
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				getAutoDeleteTimer(c1, contactId0From1));
+		// 1 creates a message
+		MessageId messageId1 = createMessageWithTimer(c1, contactId0From1);
+		// The message should have been added to 1's view of the conversation
+		headers1 = getMessageHeaders(c1, contactId0From1);
+		assertEquals(2, headers1.size());
+		assertEquals(messageId0, headers1.get(0).getId());
+		assertEquals(messageId1, headers1.get(1).getId());
+		// The message should have the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				headers1.get(1).getAutoDeleteTimer());
+		// Sync the message to 0
+		sync1To0(1, true);
+		// The message should have been added to 0's view of the conversation
+		headers0 = getMessageHeaders(c0, contactId1From0);
+		assertEquals(2, headers0.size());
+		assertEquals(messageId0, headers0.get(0).getId());
+		assertEquals(messageId1, headers0.get(1).getId());
+		// The message should have the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				headers0.get(1).getAutoDeleteTimer());
+		// 0 and 1 should both be using the new timer
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				getAutoDeleteTimer(c0, contactId1From0));
+		assertEquals(MIN_AUTO_DELETE_TIMER_MS,
+				getAutoDeleteTimer(c1, contactId0From1));
+	}
+
+	private MessageId createMessageWithoutTimer(
+			BriarIntegrationTestComponent component, ContactId contactId)
+			throws Exception {
+		DatabaseComponent db = component.getDatabaseComponent();
+		ConversationManager conversationManager =
+				component.getConversationManager();
+		MessagingManager messagingManager = component.getMessagingManager();
+		PrivateMessageFactory factory = component.getPrivateMessageFactory();
+
+		GroupId groupId = messagingManager.getConversationId(contactId);
+		return db.transactionWithResult(false, txn -> {
+			long timestamp = conversationManager
+					.getTimestampForOutgoingMessage(txn, contactId);
+			PrivateMessage m = factory.createPrivateMessage(groupId, timestamp,
+					"Hi!", emptyList());
+			messagingManager.addLocalMessage(txn, m);
+			return m.getMessage().getId();
+		});
+	}
+
+	private MessageId createMessageWithTimer(
+			BriarIntegrationTestComponent component, ContactId contactId)
+			throws Exception {
+		DatabaseComponent db = component.getDatabaseComponent();
+		ConversationManager conversationManager =
+				component.getConversationManager();
+		AutoDeleteManager autoDeleteManager = component.getAutoDeleteManager();
+		MessagingManager messagingManager = component.getMessagingManager();
+		PrivateMessageFactory factory = component.getPrivateMessageFactory();
+
+		GroupId groupId = messagingManager.getConversationId(contactId);
+		return db.transactionWithResult(false, txn -> {
+			long timestamp = conversationManager
+					.getTimestampForOutgoingMessage(txn, contactId);
+			long timer = autoDeleteManager
+					.getAutoDeleteTimer(txn, contactId, timestamp);
+			PrivateMessage m = factory.createPrivateMessage(groupId, timestamp,
+					"Hi!", emptyList(), timer);
+			messagingManager.addLocalMessage(txn, m);
+			return m.getMessage().getId();
+		});
+	}
+
+	private List<ConversationMessageHeader> getMessageHeaders(
+			BriarIntegrationTestComponent component, ContactId contactId)
+			throws Exception {
+		DatabaseComponent db = component.getDatabaseComponent();
+		MessagingManager messagingManager = component.getMessagingManager();
+
+		return sortHeaders(db.transactionWithResult(true, txn ->
+				messagingManager.getMessageHeaders(txn, contactId)));
+	}
+
+	private long getAutoDeleteTimer(BriarIntegrationTestComponent component,
+			ContactId contactId) throws DbException {
+		DatabaseComponent db = component.getDatabaseComponent();
+		AutoDeleteManager autoDeleteManager = component.getAutoDeleteManager();
+
+		return db.transactionWithResult(false,
+				txn -> autoDeleteManager.getAutoDeleteTimer(txn, contactId));
+	}
+
+	@SuppressWarnings({"UseCompareMethod", "Java8ListSort"}) // Animal Sniffer
+	private List<ConversationMessageHeader> sortHeaders(
+			Collection<ConversationMessageHeader> in) {
+		List<ConversationMessageHeader> out = new ArrayList<>(in);
+		sort(out, (a, b) ->
+				Long.valueOf(a.getTimestamp()).compareTo(b.getTimestamp()));
+		return out;
+	}
+}

briar-core/src/test/java/org/briarproject/briar/messaging/MessageSizeIntegrationTestComponent.java

@@ -3,6 +3,7 @@ package org.briarproject.briar.messaging;
 import org.briarproject.bramble.BrambleCoreIntegrationTestEagerSingletons;
 import org.briarproject.bramble.BrambleCoreModule;
 import org.briarproject.bramble.test.BrambleCoreIntegrationTestModule;
+import org.briarproject.briar.autodelete.AutoDeleteModule;
 import org.briarproject.briar.client.BriarClientModule;
 import org.briarproject.briar.forum.ForumModule;
 
@@ -12,6 +13,7 @@ import dagger.Component;
 
 @Singleton
 @Component(modules = {
+		AutoDeleteModule.class,
 		BrambleCoreIntegrationTestModule.class,
 		BrambleCoreModule.class,
 		BriarClientModule.class,

briar-core/src/test/java/org/briarproject/briar/messaging/SimplexMessagingIntegrationTestComponent.java

@@ -10,6 +10,7 @@ import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.test.BrambleCoreIntegrationTestModule;
 import org.briarproject.briar.api.messaging.MessagingManager;
 import org.briarproject.briar.api.messaging.PrivateMessageFactory;
+import org.briarproject.briar.autodelete.AutoDeleteModule;
 import org.briarproject.briar.client.BriarClientModule;
 
 import javax.inject.Singleton;
@@ -18,6 +19,7 @@ import dagger.Component;
 
 @Singleton
 @Component(modules = {
+		AutoDeleteModule.class,
 		BrambleCoreIntegrationTestModule.class,
 		BrambleCoreModule.class,
 		BriarClientModule.class,

briar-core/src/test/java/org/briarproject/briar/privategroup/invitation/AbstractProtocolEngineTest.java

@@ -153,7 +153,7 @@ abstract class AbstractProtocolEngineTest extends BrambleMockTestCase {
 		if (visible) expectGetTimestampForVisibleMessage(messageTimestamp);
 		else expectGetTimestampForInvisibleMessage(messageTimestamp);
 		expectCheckWhetherContactSupportsAutoDeletion();
-		if (visible) expectGetAutoDeleteTimer();
+		if (visible) expectGetAutoDeleteTimer(messageTimestamp);
 		context.checking(new Expectations() {{
 			oneOf(messageEncoder).encodeJoinMessage(m.getContactGroupId(),
 					m.getPrivateGroupId(), m.getTimestamp(),
@@ -167,7 +167,7 @@ abstract class AbstractProtocolEngineTest extends BrambleMockTestCase {
 		if (visible) expectGetTimestampForVisibleMessage(messageTimestamp);
 		else expectGetTimestampForInvisibleMessage(messageTimestamp);
 		expectCheckWhetherContactSupportsAutoDeletion();
-		if (visible) expectGetAutoDeleteTimer();
+		if (visible) expectGetAutoDeleteTimer(messageTimestamp);
 		context.checking(new Expectations() {{
 			oneOf(messageEncoder).encodeLeaveMessage(contactGroupId,
 					privateGroupId, messageTimestamp, lastLocalMessageId,
@@ -254,10 +254,28 @@ abstract class AbstractProtocolEngineTest extends BrambleMockTestCase {
 		}});
 	}
 
-	void expectGetAutoDeleteTimer() throws Exception {
+	void expectGetAutoDeleteTimer(long timestamp) throws Exception {
 		context.checking(new Expectations() {{
-			oneOf(autoDeleteManager).getAutoDeleteTimer(txn, contactId);
+			oneOf(autoDeleteManager).getAutoDeleteTimer(txn, contactId,
+					timestamp);
 			will(returnValue(NO_AUTO_DELETE_TIMER));
 		}});
 	}
+
+	void expectTrackUnreadMessage(long timestamp) throws Exception {
+		context.checking(new Expectations() {{
+			oneOf(messageTracker).trackMessage(txn, contactGroupId, timestamp,
+					false);
+		}});
+	}
+
+	void expectReceiveAutoDeleteTimer(DeletableGroupInvitationMessage m)
+			throws Exception {
+		context.checking(new Expectations() {{
+			oneOf(clientHelper).getContactId(txn, contactGroupId);
+			will(returnValue(contactId));
+			oneOf(autoDeleteManager).receiveAutoDeleteTimer(txn, contactId,
+					m.getAutoDeleteTimer(), m.getTimestamp());
+		}});
+	}
 }

briar-core/src/test/java/org/briarproject/briar/privategroup/invitation/CreatorProtocolEngineTest.java

@@ -308,11 +308,8 @@ public class CreatorProtocolEngineTest extends AbstractProtocolEngineTest {
 
 		expectSendJoinMessage(properJoinMessage, false);
 		expectMarkMessageVisibleInUi(properJoinMessage.getId());
-		context.checking(new Expectations() {{
-			oneOf(messageTracker)
-					.trackMessage(txn, contactGroupId, inviteTimestamp + 1,
-							false);
-		}});
+		expectTrackUnreadMessage(properJoinMessage.getTimestamp());
+		expectReceiveAutoDeleteTimer(properJoinMessage);
 		expectGetContactId();
 		expectSetPrivateGroupVisibility(SHARED);
 		CreatorSession newSession =
@@ -399,11 +396,8 @@ public class CreatorProtocolEngineTest extends AbstractProtocolEngineTest {
 		CreatorSession session = getDefaultSession(INVITED);
 
 		expectMarkMessageVisibleInUi(properLeaveMessage.getId());
-		context.checking(new Expectations() {{
-			oneOf(messageTracker)
-					.trackMessage(txn, contactGroupId, inviteTimestamp + 1,
-							false);
-		}});
+		expectTrackUnreadMessage(properLeaveMessage.getTimestamp());
+		expectReceiveAutoDeleteTimer(properLeaveMessage);
 		expectGetContactId();
 		CreatorSession newSession =
 				engine.onLeaveMessage(txn, session, properLeaveMessage);

briar-core/src/test/java/org/briarproject/briar/privategroup/invitation/GroupInvitationIntegrationTest.java

@@ -168,8 +168,8 @@ public class GroupInvitationIntegrationTest
 	@Test
 	public void testInvitationDeclineWithAutoDelete() throws Exception {
 		// 0 and 1 set an auto-delete timer for their conversation
-		setAutoDeleteTimer(c0, contactId1From0);
-		setAutoDeleteTimer(c1, contactId0From1);
+		setAutoDeleteTimer(c0, contactId1From0, MIN_AUTO_DELETE_TIMER_MS);
+		setAutoDeleteTimer(c1, contactId0From1, MIN_AUTO_DELETE_TIMER_MS);
 
 		// Send invitation
 		sendInvitation(clock.currentTimeMillis(), null);
@@ -253,8 +253,8 @@ public class GroupInvitationIntegrationTest
 	@Test
 	public void testInvitationAcceptWithAutoDelete() throws Exception {
 		// 0 and 1 set an auto-delete timer for their conversation
-		setAutoDeleteTimer(c0, contactId1From0);
-		setAutoDeleteTimer(c1, contactId0From1);
+		setAutoDeleteTimer(c0, contactId1From0, MIN_AUTO_DELETE_TIMER_MS);
+		setAutoDeleteTimer(c1, contactId0From1, MIN_AUTO_DELETE_TIMER_MS);
 
 		// Send invitation
 		sendInvitation(clock.currentTimeMillis(), null);
@@ -743,7 +743,7 @@ public class GroupInvitationIntegrationTest
 			throws DbException {
 		byte[] signature = groupInvitationFactory.signInvitation(contact1From0,
 				privateGroup.getId(), timestamp, author0.getPrivateKey());
-		long timer = getAutoDeleteTimer(c0, contactId1From0);
+		long timer = getAutoDeleteTimer(c0, contactId1From0, timestamp);
 		groupInvitationManager0.sendInvitation(privateGroup.getId(),
 				contactId1From0, text, timestamp, signature, timer);
 	}

briar-core/src/test/java/org/briarproject/briar/privategroup/invitation/InviteeProtocolEngineTest.java

@@ -366,9 +366,9 @@ public class InviteeProtocolEngineTest extends AbstractProtocolEngineTest {
 		}});
 		expectMarkMessageVisibleInUi(properInviteMessage.getId());
 		expectMarkMessageAvailableToAnswer(properInviteMessage.getId(), true);
+		expectTrackUnreadMessage(properInviteMessage.getTimestamp());
+		expectReceiveAutoDeleteTimer(properInviteMessage);
 		context.checking(new Expectations() {{
-			oneOf(messageTracker).trackMessage(txn, contactGroupId,
-					properInviteMessage.getTimestamp(), false);
 			oneOf(privateGroupFactory)
 					.createPrivateGroup(properInviteMessage.getGroupName(),
 							properInviteMessage.getCreator(),

briar-core/src/test/java/org/briarproject/briar/sharing/BlogSharingIntegrationTest.java

@@ -210,8 +210,8 @@ public class BlogSharingIntegrationTest
 		listenToEvents(true);
 
 		// Set an auto-delete timer for the conversation
-		setAutoDeleteTimer(c0, contactId1From0);
-		setAutoDeleteTimer(c1, contactId0From1);
+		setAutoDeleteTimer(c0, contactId1From0, MIN_AUTO_DELETE_TIMER_MS);
+		setAutoDeleteTimer(c1, contactId0From1, MIN_AUTO_DELETE_TIMER_MS);
 
 		// Send invitation
 		blogSharingManager0

briar-core/src/test/java/org/briarproject/briar/sharing/ForumSharingIntegrationTest.java

@@ -191,8 +191,8 @@ public class ForumSharingIntegrationTest
 	@Test
 	public void testSuccessfulSharingWithAutoDelete() throws Exception {
 		// Set an auto-delete timer for the conversation
-		setAutoDeleteTimer(c0, contactId1From0);
-		setAutoDeleteTimer(c1, contactId0From1);
+		setAutoDeleteTimer(c0, contactId1From0, MIN_AUTO_DELETE_TIMER_MS);
+		setAutoDeleteTimer(c1, contactId0From1, MIN_AUTO_DELETE_TIMER_MS);
 
 		// Send invitation
 		forumSharingManager0

briar-core/src/test/java/org/briarproject/briar/test/BriarIntegrationTest.java

@@ -30,6 +30,7 @@ import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.test.TestTransportConnectionReader;
 import org.briarproject.bramble.test.TestTransportConnectionWriter;
 import org.briarproject.bramble.test.TestUtils;
+import org.briarproject.briar.api.autodelete.AutoDeleteManager;
 import org.briarproject.briar.api.blog.BlogFactory;
 import org.briarproject.briar.api.blog.BlogPostFactory;
 import org.briarproject.briar.api.client.MessageTracker;
@@ -63,7 +64,6 @@ import static org.briarproject.bramble.api.sync.validation.MessageState.PENDING;
 import static org.briarproject.bramble.test.TestPluginConfigModule.SIMPLEX_TRANSPORT_ID;
 import static org.briarproject.bramble.test.TestUtils.getSecretKey;
 import static org.briarproject.bramble.util.LogUtils.logException;
-import static org.briarproject.briar.api.autodelete.AutoDeleteConstants.MIN_AUTO_DELETE_TIMER_MS;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
@@ -453,16 +453,21 @@ public abstract class BriarIntegrationTest<C extends BriarIntegrationTestCompone
 	}
 
 	protected void setAutoDeleteTimer(BriarIntegrationTestComponent component,
-			ContactId contactId) throws DbException {
-		component.getDatabaseComponent().transaction(false, txn ->
-				component.getAutoDeleteManager().setAutoDeleteTimer(txn,
-						contactId, MIN_AUTO_DELETE_TIMER_MS));
+			ContactId contactId, long timer) throws DbException {
+		DatabaseComponent db = component.getDatabaseComponent();
+		AutoDeleteManager autoDeleteManager = component.getAutoDeleteManager();
+
+		db.transaction(false, txn ->
+				autoDeleteManager.setAutoDeleteTimer(txn, contactId, timer));
 	}
 
 	protected long getAutoDeleteTimer(BriarIntegrationTestComponent component,
-			ContactId contactId) throws DbException {
-		return component.getDatabaseComponent().transactionWithResult(true,
-				txn -> component.getAutoDeleteManager().getAutoDeleteTimer(txn,
-						contactId));
+			ContactId contactId, long timestamp) throws DbException {
+		DatabaseComponent db = component.getDatabaseComponent();
+		AutoDeleteManager autoDeleteManager = component.getAutoDeleteManager();
+
+		return db.transactionWithResult(false,
+				txn -> autoDeleteManager.getAutoDeleteTimer(txn, contactId,
+						timestamp));
 	}
 }