Bump version numbers for 1.5.7 release.

Catch SecurityException for bluetooth_address setting

See merge request briar/briar!1811

.gitlab-ci.yml

@@ -83,29 +83,14 @@ android test:
 test_reproducible:
   stage: check_reproducibility
   script:
-    - "curl -X POST -F token=${RELEASE_CHECK_TOKEN} -F ref=master -F variables[RELEASE_TAG]=${CI_COMMIT_REF_NAME} https://code.briarproject.org/api/v4/projects/61/trigger/pipeline"
+    - "curl -X POST -F token=${RELEASE_CHECK_TOKEN} -F ref=master -F variables[APP]='briar' -F variables[RELEASE_TAG]=${CI_COMMIT_REF_NAME} https://code.briarproject.org/api/v4/projects/61/trigger/pipeline"
+    - "curl -X POST -F token=${RELEASE_JAR_CHECK_TOKEN} -F ref=main -F variables[APP]='briar-headless' -F variables[RELEASE_TAG]=${CI_COMMIT_REF_NAME} https://code.briarproject.org/api/v4/projects/307/trigger/pipeline"
   only:
     - tags
 
-.optional_tests:
+mailbox integration test:
   stage: optional_tests
   extends: .base-test
-
-bridge test:
-  extends: .optional_tests
-  rules:
-    - if: '$CI_PIPELINE_SOURCE == "schedule"'
-      when: on_success
-      allow_failure: false
-    - if: '$CI_COMMIT_TAG == null'
-      when: manual
-      allow_failure: true
-  script:
-    - OPTIONAL_TESTS=org.briarproject.bramble.plugin.tor.BridgeTest ./gradlew --info bramble-java:test --tests BridgeTest
-  timeout: 4h
-
-mailbox integration test:
-  extends: .optional_tests
   rules:
     - changes:
         - mailbox-integration-tests/**/*

.idea/runConfigurations/BridgeTest.xml

@@ -1,28 +0,0 @@
-<component name="ProjectRunConfigurationManager">
-  <configuration default="false" name="BridgeTest" type="GradleRunConfiguration" factoryName="Gradle">
-    <ExternalSystemSettings>
-      <option name="env">
-        <map>
-          <entry key="OPTIONAL_TESTS" value="org.briarproject.bramble.plugin.tor.BridgeTest" />
-        </map>
-      </option>
-      <option name="executionName" />
-      <option name="externalProjectPath" value="$PROJECT_DIR$" />
-      <option name="externalSystemIdString" value="GRADLE" />
-      <option name="scriptParameters" value="--tests &quot;org.briarproject.bramble.plugin.tor.BridgeTest&quot;" />
-      <option name="taskDescriptions">
-        <list />
-      </option>
-      <option name="taskNames">
-        <list>
-          <option value=":bramble-java:test" />
-        </list>
-      </option>
-      <option name="vmOptions" value="" />
-    </ExternalSystemSettings>
-    <ExternalSystemDebugServerProcess>false</ExternalSystemDebugServerProcess>
-    <ExternalSystemReattachDebugProcess>true</ExternalSystemReattachDebugProcess>
-    <DebugAllEnabled>false</DebugAllEnabled>
-    <method v="2" />
-  </configuration>
-</component>

README.md

@@ -1,7 +1,7 @@
 # Briar
 Briar is a messaging app designed for activists, journalists, and anyone else who needs a safe, easy and robust way to communicate.
 
-Unlike traditional messaging tools such as email, Twitter or Telegram, Briar doesn't rely on a central server - messages are synchronized directly between the users' devices. 
+Unlike traditional messaging apps, Briar doesn't rely on a central server - messages are synchronized directly between the users' devices. 
 
 If the Internet's down, Briar can sync via Bluetooth or Wi-Fi, keeping information flowing in a crisis. If the Internet's up, Briar can sync via the Tor network, protecting users and their relationships from surveillance.
 
@@ -14,14 +14,16 @@ You can also [download the APK file](https://briarproject.org/apk) directly from
 our site.
 
 ## Useful links
-[briarproject.org](https://briarproject.org/)
+[Project website](https://briarproject.org/)
 
 [Source code](https://code.briarproject.org/briar/briar/tree/master)
 
-[Manual](https://briarproject.org/manual/)
+[User manual](https://briarproject.org/manual/)
 
 [Wiki](https://code.briarproject.org/briar/briar/-/wikis/home)
 
+[Privacy policy](https://briarproject.org/privacy)
+
 ## Reproducible builds
 
 We provide [docker images](https://code.briarproject.org/briar/briar-reproducer#briar-reproducer)
@@ -33,5 +35,5 @@ for reproduction.
 
 ## Donate
 
-[![Donate using Liberapay](https://briarproject.org/img/liberapay.svg)](https://liberapay.com/Briar/donate) [![Flattr this](https://briarproject.org/img/flattr-badge-large.png "Flattr this")](https://flattr.com/t/592836/)   
+[![Donate using Liberapay](https://briarproject.org/img/liberapay.svg)](https://liberapay.com/Briar/donate)   
 Bitcoin and BCH: 1NZCKkUCtJV2U2Y9hDb9uq8S7ksFCFGR6K

bramble-android/build.gradle

@@ -11,10 +11,10 @@ android {
 	}
 
 	defaultConfig {
-		minSdkVersion 16
-		targetSdkVersion 31
-		versionCode 10418
-		versionName "1.4.18"
+		minSdkVersion 21
+		targetSdkVersion 33
+		versionCode 10507
+		versionName "1.5.7"
 		consumerProguardFiles 'proguard-rules.txt'
 
 		testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
@@ -40,6 +40,8 @@ configurations {
 }
 
 dependencies {
+	api 'org.briarproject:dont-kill-me-lib:0.2.7'
+
 	// In theory this dependency shouldn't be needed, but without it Android Studio's linter will
 	// complain about unresolved symbols for bramble-api test classes in bramble-android tests,
 	// even though the bramble-api test classes are provided by the testImplementation dependency
@@ -49,6 +51,7 @@ dependencies {
 	implementation project(':bramble-core')
 
 	implementation 'androidx.annotation:annotation:1.5.0'
+	implementation "org.briarproject:onionwrapper-android:$onionwrapper_version"
 
 	tor "org.briarproject:tor-android:$tor_version"
 	tor "org.briarproject:obfs4proxy-android:$obfs4proxy_version"
@@ -71,7 +74,7 @@ def torLibsDir = 'src/main/jniLibs'
 task cleanTorBinaries {
 	outputs.dir torLibsDir
 	doLast {
-		delete fileTree(torLibsDir) { include '**/*.so' }
+		delete fileTree(torLibsDir)
 	}
 }
 
@@ -80,34 +83,9 @@ clean.dependsOn cleanTorBinaries
 task unpackTorBinaries {
 	outputs.dir torLibsDir
 	doLast {
-		configurations.tor.each { outer ->
-			zipTree(outer).each { inner ->
-				if (inner.name.endsWith('_arm_pie.zip')) {
-					copy {
-						from zipTree(inner)
-						into torLibsDir
-						rename '(.*)', 'armeabi-v7a/lib$1.so'
-					}
-				} else if (inner.name.endsWith('_arm64_pie.zip')) {
-					copy {
-						from zipTree(inner)
-						into torLibsDir
-						rename '(.*)', 'arm64-v8a/lib$1.so'
-					}
-				} else if (inner.name.endsWith('_x86_pie.zip')) {
-					copy {
-						from zipTree(inner)
-						into torLibsDir
-						rename '(.*)', 'x86/lib$1.so'
-					}
-				} else if (inner.name.endsWith('_x86_64_pie.zip')) {
-					copy {
-						from zipTree(inner)
-						into torLibsDir
-						rename '(.*)', 'x86_64/lib$1.so'
-					}
-				}
-			}
+		copy {
+			from configurations.tor.collect { zipTree(it) }
+			into torLibsDir
 		}
 	}
 	dependsOn cleanTorBinaries

bramble-android/src/main/AndroidManifest.xml

@@ -1,4 +1,5 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
+	xmlns:tools="http://schemas.android.com/tools"
 	package="org.briarproject.bramble">
 
 	<uses-feature
@@ -7,15 +8,17 @@
 
 	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
 	<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+	<!-- The BLUETOOTH permission was supposed to be removed in API 31 but is still needed on some Xiaomi/Redmi/POCO devices running API 31 and Nubia devices running API 32 -->
 	<uses-permission
 		android:name="android.permission.BLUETOOTH"
-		android:maxSdkVersion="30" />
+		android:maxSdkVersion="32" />
 	<uses-permission
 		android:name="android.permission.BLUETOOTH_ADMIN"
 		android:maxSdkVersion="30" />
 	<uses-permission
 		android:name="android.permission.BLUETOOTH_SCAN"
-		android:usesPermissionFlags="neverForLocation" />
+		android:usesPermissionFlags="neverForLocation"
+		tools:targetApi="31" />
 	<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
 	<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
 	<uses-permission android:name="android.permission.INTERNET" />

bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidModule.java

@@ -8,6 +8,7 @@ import org.briarproject.bramble.reporting.ReportingModule;
 import org.briarproject.bramble.socks.SocksModule;
 import org.briarproject.bramble.system.AndroidSystemModule;
 import org.briarproject.bramble.system.AndroidTaskSchedulerModule;
+import org.briarproject.bramble.system.AndroidWakeLockModule;
 import org.briarproject.bramble.system.AndroidWakefulIoExecutorModule;
 import org.briarproject.bramble.system.DefaultThreadFactoryModule;
 
@@ -19,6 +20,7 @@ import dagger.Module;
 		AndroidSystemModule.class,
 		AndroidTaskSchedulerModule.class,
 		AndroidWakefulIoExecutorModule.class,
+		AndroidWakeLockModule.class,
 		DefaultThreadFactoryModule.class,
 		CircumventionModule.class,
 		DnsModule.class,

bramble-android/src/main/java/org/briarproject/bramble/account/AndroidAccountManager.java

@@ -20,7 +20,6 @@ import javax.annotation.Nullable;
 import javax.annotation.concurrent.GuardedBy;
 import javax.inject.Inject;
 
-import static android.os.Build.VERSION.SDK_INT;
 import static java.util.Arrays.asList;
 import static java.util.logging.Level.INFO;
 import static org.briarproject.bramble.util.IoUtils.deleteFileOrDir;
@@ -105,15 +104,11 @@ class AndroidAccountManager extends AccountManagerImpl
 		}
 		files.add(appContext.getFilesDir());
 		addIfNotNull(files, appContext.getExternalCacheDir());
-		if (SDK_INT >= 19) {
-			for (File file : appContext.getExternalCacheDirs()) {
-				addIfNotNull(files, file);
-			}
+		for (File file : appContext.getExternalCacheDirs()) {
+			addIfNotNull(files, file);
 		}
-		if (SDK_INT >= 21) {
-			for (File file : appContext.getExternalMediaDirs()) {
-				addIfNotNull(files, file);
-			}
+		for (File file : appContext.getExternalMediaDirs()) {
+			addIfNotNull(files, file);
 		}
 		// Clear the cache directory but don't delete it
 		File cacheDir = appContext.getCacheDir();

bramble-android/src/main/java/org/briarproject/bramble/api/system/AndroidWakeLock.java

@@ -1,19 +0,0 @@
-package org.briarproject.bramble.api.system;
-
-import org.briarproject.nullsafety.NotNullByDefault;
-
-@NotNullByDefault
-public interface AndroidWakeLock {
-
-	/**
-	 * Acquires the wake lock. This has no effect if the wake lock has already
-	 * been acquired.
-	 */
-	void acquire();
-
-	/**
-	 * Releases the wake lock. This has no effect if the wake lock has already
-	 * been released.
-	 */
-	void release();
-}

bramble-android/src/main/java/org/briarproject/bramble/api/system/AndroidWakeLockManager.java

@@ -1,38 +0,0 @@
-package org.briarproject.bramble.api.system;
-
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.util.concurrent.Executor;
-
-@NotNullByDefault
-public interface AndroidWakeLockManager {
-
-	/**
-	 * Creates a wake lock with the given tag. The tag is only used for
-	 * logging; the underlying OS wake lock will use its own tag.
-	 */
-	AndroidWakeLock createWakeLock(String tag);
-
-	/**
-	 * Runs the given task while holding a wake lock.
-	 */
-	void runWakefully(Runnable r, String tag);
-
-	/**
-	 * Submits the given task to the given executor while holding a wake lock.
-	 * The lock is released when the task completes, or if an exception is
-	 * thrown while submitting or running the task.
-	 */
-	void executeWakefully(Runnable r, Executor executor, String tag);
-
-	/**
-	 * Starts a dedicated thread to run the given task asynchronously. A wake
-	 * lock is acquired before starting the thread and released when the task
-	 * completes, or if an exception is thrown while starting the thread or
-	 * running the task.
-	 * <p>
-	 * This method should only be used for lifecycle management tasks that
-	 * can't be run on an executor.
-	 */
-	void executeWakefully(Runnable r, String tag);
-}

bramble-android/src/main/java/org/briarproject/bramble/battery/AndroidBatteryManager.java

@@ -5,6 +5,7 @@ import android.content.BroadcastReceiver;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.os.PowerManager;
 
 import org.briarproject.bramble.api.battery.BatteryManager;
 import org.briarproject.bramble.api.battery.event.BatteryEvent;
@@ -16,10 +17,17 @@ import java.util.logging.Logger;
 
 import javax.inject.Inject;
 
+import androidx.annotation.RequiresApi;
+
 import static android.content.Intent.ACTION_BATTERY_CHANGED;
 import static android.content.Intent.ACTION_POWER_CONNECTED;
 import static android.content.Intent.ACTION_POWER_DISCONNECTED;
 import static android.os.BatteryManager.EXTRA_PLUGGED;
+import static android.os.Build.VERSION.SDK_INT;
+import static android.os.PowerManager.ACTION_DEVICE_IDLE_MODE_CHANGED;
+import static android.os.PowerManager.ACTION_DEVICE_LIGHT_IDLE_MODE_CHANGED;
+import static android.os.PowerManager.ACTION_LOW_POWER_STANDBY_ENABLED_CHANGED;
+import static android.os.PowerManager.ACTION_POWER_SAVE_MODE_CHANGED;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Logger.getLogger;
 
@@ -57,6 +65,12 @@ class AndroidBatteryManager implements BatteryManager, Service {
 		IntentFilter filter = new IntentFilter();
 		filter.addAction(ACTION_POWER_CONNECTED);
 		filter.addAction(ACTION_POWER_DISCONNECTED);
+		filter.addAction(ACTION_POWER_SAVE_MODE_CHANGED);
+		if (SDK_INT >= 23) filter.addAction(ACTION_DEVICE_IDLE_MODE_CHANGED);
+		if (SDK_INT >= 33) {
+			filter.addAction(ACTION_LOW_POWER_STANDBY_ENABLED_CHANGED);
+			filter.addAction(ACTION_DEVICE_LIGHT_IDLE_MODE_CHANGED);
+		}
 		appContext.registerReceiver(batteryReceiver, filter);
 	}
 
@@ -76,6 +90,33 @@ class AndroidBatteryManager implements BatteryManager, Service {
 				eventBus.broadcast(new BatteryEvent(true));
 			else if (ACTION_POWER_DISCONNECTED.equals(action))
 				eventBus.broadcast(new BatteryEvent(false));
+			else if (SDK_INT >= 23 &&
+					ACTION_DEVICE_IDLE_MODE_CHANGED.equals(action) &&
+					LOG.isLoggable(INFO)) {
+				LOG.info("Device idle mode changed to: " +
+						getPowerManager(ctx).isDeviceIdleMode());
+			} else if (SDK_INT >= 23 &&
+					ACTION_POWER_SAVE_MODE_CHANGED.equals(action) &&
+					LOG.isLoggable(INFO)) {
+				LOG.info("Power save mode changed to: " +
+						getPowerManager(ctx).isPowerSaveMode());
+			} else if (SDK_INT >= 33 && LOG.isLoggable(INFO) &&
+					ACTION_LOW_POWER_STANDBY_ENABLED_CHANGED.equals(action)) {
+				PowerManager powerManager =
+						ctx.getSystemService(PowerManager.class);
+				LOG.info("Low power standby now is: " +
+						powerManager.isLowPowerStandbyEnabled());
+			} else if (SDK_INT >= 33 && LOG.isLoggable(INFO) &&
+					ACTION_DEVICE_LIGHT_IDLE_MODE_CHANGED.equals(action)) {
+				PowerManager powerManager = getPowerManager(ctx);
+				LOG.info("Light idle mode now is: " +
+						powerManager.isDeviceLightIdleMode());
+			}
 		}
 	}
+
+	@RequiresApi(api = 23)
+	private PowerManager getPowerManager(Context ctx) {
+		return ctx.getSystemService(PowerManager.class);
+	}
 }

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

@@ -118,6 +118,11 @@ class AndroidNetworkManager implements NetworkManager, Service {
 		try {
 			NetworkInfo net = connectivityManager.getActiveNetworkInfo();
 			boolean connected = net != null && net.isConnected();
+			// Research into Android's behavior to check network connectivity
+			// (https://code.briarproject.org/briar/public-mesh-research/-/issues/19)
+			// has shown that NetworkInfo#isConnected() returns true if the device
+			// is connected to any Wifi, independent of whether any specific IP
+			// address can be reached using it or any domain names can be resolved.
 			boolean wifi = false, ipv6Only = false;
 			if (connected) {
 				wifi = net.getType() == TYPE_WIFI;

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

@@ -2,10 +2,10 @@ package org.briarproject.bramble.plugin.bluetooth;
 
 import android.bluetooth.BluetoothSocket;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.io.TimeoutMonitor;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.IOException;

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

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.plugin.bluetooth;
 
+import android.annotation.SuppressLint;
 import android.app.Application;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
@@ -49,7 +50,6 @@ import static android.bluetooth.BluetoothAdapter.STATE_ON;
 import static android.bluetooth.BluetoothDevice.ACTION_FOUND;
 import static android.bluetooth.BluetoothDevice.DEVICE_TYPE_LE;
 import static android.bluetooth.BluetoothDevice.EXTRA_DEVICE;
-import static android.os.Build.VERSION.SDK_INT;
 import static java.util.Collections.shuffle;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static java.util.logging.Level.INFO;
@@ -60,6 +60,7 @@ import static org.briarproject.bramble.util.PrivacyUtils.scrubMacAddress;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
+@SuppressLint("MissingPermission")
 class AndroidBluetoothPlugin extends
 		AbstractBluetoothPlugin<BluetoothSocket, BluetoothServerSocket> {
 
@@ -253,7 +254,7 @@ class AndroidBluetoothPlugin extends
 					} else if (ACTION_FOUND.equals(action)) {
 						BluetoothDevice d = i.getParcelableExtra(EXTRA_DEVICE);
 						// Ignore Bluetooth LE devices
-						if (SDK_INT < 18 || d.getType() != DEVICE_TYPE_LE) {
+						if (d.getType() != DEVICE_TYPE_LE) {
 							String address = d.getAddress();
 							if (LOG.isLoggable(INFO))
 								LOG.info("Discovered " +

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

@@ -3,6 +3,7 @@ package org.briarproject.bramble.plugin.bluetooth;
 import android.app.Application;
 import android.bluetooth.BluetoothSocket;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.io.TimeoutMonitor;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
@@ -13,7 +14,6 @@ import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
 import org.briarproject.bramble.api.system.AndroidExecutor;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.WakefulIoExecutor;
 import org.briarproject.nullsafety.NotNullByDefault;

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

@@ -2,11 +2,11 @@ package org.briarproject.bramble.plugin.bluetooth;
 
 import android.bluetooth.BluetoothSocket;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLock;
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.io.TimeoutMonitor;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.plugin.duplex.AbstractDuplexTransportConnection;
-import org.briarproject.bramble.api.system.AndroidWakeLock;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.IOException;
@@ -33,8 +33,10 @@ class AndroidBluetoothTransportConnection
 		super(plugin);
 		this.connectionLimiter = connectionLimiter;
 		this.socket = socket;
-		in = timeoutMonitor.createTimeoutInputStream(
-				socket.getInputStream(), plugin.getMaxIdleTime() * 2);
+		InputStream socketIn = socket.getInputStream();
+		if (socketIn == null) throw new IOException();
+		in = timeoutMonitor.createTimeoutInputStream(socketIn,
+				plugin.getMaxIdleTime() * 2L);
 		wakeLock = wakeLockManager.createWakeLock("BluetoothConnection");
 		wakeLock.acquire();
 		String address = socket.getRemoteDevice().getAddress();
@@ -48,7 +50,9 @@ class AndroidBluetoothTransportConnection
 
 	@Override
 	protected OutputStream getOutputStream() throws IOException {
-		return socket.getOutputStream();
+		OutputStream socketOut = socket.getOutputStream();
+		if (socketOut == null) throw new IOException();
+		return socketOut;
 	}
 
 	@Override

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

@@ -1,6 +1,5 @@
 package org.briarproject.bramble.plugin.tcp;
 
-import android.annotation.TargetApi;
 import android.app.Application;
 import android.net.ConnectivityManager;
 import android.net.LinkAddress;
@@ -37,7 +36,6 @@ import javax.net.SocketFactory;
 import static android.content.Context.CONNECTIVITY_SERVICE;
 import static android.content.Context.WIFI_SERVICE;
 import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
-import static android.os.Build.VERSION.SDK_INT;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.list;
 import static java.util.Collections.singletonList;
@@ -118,7 +116,7 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 		// If there's no wifi IPv4 address, we might be a client on an
 		// IPv6-only wifi network. We can only detect this on API 21+
 		if (wifi == null) {
-			return SDK_INT >= 21 ? getWifiClientIpv6Address() : null;
+			return getWifiClientIpv6Address();
 		}
 		// Use the wifi IPv4 address to determine which interface's IPv6
 		// address we should return (if the interface has a suitable address)
@@ -172,7 +170,6 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 	 * Returns a link-local IPv6 address for the wifi client interface, or null
 	 * if there's no such interface or it doesn't have a suitable address.
 	 */
-	@TargetApi(21)
 	@Nullable
 	private InetAddress getWifiClientIpv6Address() {
 		// https://issuetracker.google.com/issues/175055271
@@ -204,6 +201,7 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 	@Nullable
 	private InetAddress getIpv6AddressForInterface(InetAddress ipv4) {
 		try {
+			// We may get an NPE from getByInetAddress() on Android 11
 			NetworkInterface iface = NetworkInterface.getByInetAddress(ipv4);
 			if (iface == null) return null;
 			for (InetAddress addr : list(iface.getInetAddresses())) {
@@ -211,7 +209,7 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 			}
 			// No suitable address
 			return null;
-		} catch (SocketException e) {
+		} catch (SocketException | NullPointerException e) {
 			logException(LOG, WARNING, e);
 			return null;
 		}
@@ -234,7 +232,6 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 	// On API 21 and later, a socket that is not created with the wifi
 	// network's socket factory may try to connect via another network
 	private SocketFactory getSocketFactory() {
-		if (SDK_INT < 21) return SocketFactory.getDefault();
 		// https://issuetracker.google.com/issues/175055271
 		try {
 			for (Network net : connectivityManager.getAllNetworks()) {
@@ -302,7 +299,7 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 		Pair<InetAddress, Boolean> wifi = getWifiIpv4Address();
 		// If there's no wifi IPv4 address, we might be a client on an
 		// IPv6-only wifi network. We can only detect this on API 21+
-		if (wifi == null && SDK_INT >= 21) {
+		if (wifi == null) {
 			InetAddress ipv6 = getWifiClientIpv6Address();
 			if (ipv6 != null) return new Pair<>(ipv6, false);
 		}

bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPlugin.java

@@ -1,238 +0,0 @@
-package org.briarproject.bramble.plugin.tor;
-
-import android.app.Application;
-import android.content.pm.PackageInfo;
-import android.content.pm.PackageManager;
-import android.content.pm.PackageManager.NameNotFoundException;
-
-import org.briarproject.bramble.api.battery.BatteryManager;
-import org.briarproject.bramble.api.network.NetworkManager;
-import org.briarproject.bramble.api.plugin.Backoff;
-import org.briarproject.bramble.api.plugin.PluginCallback;
-import org.briarproject.bramble.api.system.AndroidWakeLock;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
-import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.api.system.ResourceProvider;
-import org.briarproject.bramble.util.AndroidUtils;
-import org.briarproject.nullsafety.MethodsNotNullByDefault;
-import org.briarproject.nullsafety.ParametersNotNullByDefault;
-
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileNotFoundException;
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.concurrent.Executor;
-import java.util.logging.Logger;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipInputStream;
-
-import javax.net.SocketFactory;
-
-import androidx.annotation.ChecksSdkIntAtLeast;
-
-import static android.os.Build.VERSION.SDK_INT;
-import static java.util.Arrays.asList;
-import static java.util.logging.Level.INFO;
-import static java.util.logging.Logger.getLogger;
-
-@MethodsNotNullByDefault
-@ParametersNotNullByDefault
-class AndroidTorPlugin extends TorPlugin {
-
-	private static final List<String> LIBRARY_ARCHITECTURES =
-			asList("armeabi-v7a", "arm64-v8a", "x86", "x86_64");
-
-	private static final String TOR_LIB_NAME = "libtor.so";
-	private static final String OBFS4_LIB_NAME = "libobfs4proxy.so";
-	private static final String SNOWFLAKE_LIB_NAME = "libsnowflake.so";
-
-	private static final Logger LOG =
-			getLogger(AndroidTorPlugin.class.getName());
-
-	private final Application app;
-	private final AndroidWakeLock wakeLock;
-	private final File torLib, obfs4Lib, snowflakeLib;
-
-	AndroidTorPlugin(Executor ioExecutor,
-			Executor wakefulIoExecutor,
-			Application app,
-			NetworkManager networkManager,
-			LocationUtils locationUtils,
-			SocketFactory torSocketFactory,
-			Clock clock,
-			ResourceProvider resourceProvider,
-			CircumventionProvider circumventionProvider,
-			BatteryManager batteryManager,
-			AndroidWakeLockManager wakeLockManager,
-			Backoff backoff,
-			TorRendezvousCrypto torRendezvousCrypto,
-			PluginCallback callback,
-			String architecture,
-			long maxLatency,
-			int maxIdleTime,
-			File torDirectory,
-			int torSocksPort,
-			int torControlPort) {
-		super(ioExecutor, wakefulIoExecutor, networkManager, locationUtils,
-				torSocketFactory, clock, resourceProvider,
-				circumventionProvider, batteryManager, backoff,
-				torRendezvousCrypto, callback, architecture, maxLatency,
-				maxIdleTime, torDirectory, torSocksPort, torControlPort);
-		this.app = app;
-		wakeLock = wakeLockManager.createWakeLock("TorPlugin");
-		String nativeLibDir = app.getApplicationInfo().nativeLibraryDir;
-		torLib = new File(nativeLibDir, TOR_LIB_NAME);
-		obfs4Lib = new File(nativeLibDir, OBFS4_LIB_NAME);
-		snowflakeLib = new File(nativeLibDir, SNOWFLAKE_LIB_NAME);
-	}
-
-	@Override
-	protected int getProcessId() {
-		return android.os.Process.myPid();
-	}
-
-	@Override
-	protected long getLastUpdateTime() {
-		try {
-			PackageManager pm = app.getPackageManager();
-			PackageInfo pi = pm.getPackageInfo(app.getPackageName(), 0);
-			return pi.lastUpdateTime;
-		} catch (NameNotFoundException e) {
-			throw new AssertionError(e);
-		}
-	}
-
-	@Override
-	protected void enableNetwork(boolean enable) throws IOException {
-		if (enable) wakeLock.acquire();
-		super.enableNetwork(enable);
-		if (!enable) wakeLock.release();
-	}
-
-	@Override
-	@ChecksSdkIntAtLeast(api = 25)
-	protected boolean canVerifyLetsEncryptCerts() {
-		return SDK_INT >= 25;
-	}
-
-	@Override
-	public void stop() {
-		super.stop();
-		wakeLock.release();
-	}
-
-	@Override
-	protected File getTorExecutableFile() {
-		return torLib.exists() ? torLib : super.getTorExecutableFile();
-	}
-
-	@Override
-	protected File getObfs4ExecutableFile() {
-		return obfs4Lib.exists() ? obfs4Lib : super.getObfs4ExecutableFile();
-	}
-
-	@Override
-	protected File getSnowflakeExecutableFile() {
-		return snowflakeLib.exists()
-				? snowflakeLib : super.getSnowflakeExecutableFile();
-	}
-
-	@Override
-	protected void installTorExecutable() throws IOException {
-		installExecutable(super.getTorExecutableFile(), torLib, TOR_LIB_NAME);
-	}
-
-	@Override
-	protected void installObfs4Executable() throws IOException {
-		installExecutable(super.getObfs4ExecutableFile(), obfs4Lib,
-				OBFS4_LIB_NAME);
-	}
-
-	@Override
-	protected void installSnowflakeExecutable() throws IOException {
-		installExecutable(super.getSnowflakeExecutableFile(), snowflakeLib,
-				SNOWFLAKE_LIB_NAME);
-	}
-
-	private void installExecutable(File extracted, File lib, String libName)
-			throws IOException {
-		if (lib.exists()) {
-			// If an older version left behind a binary, delete it
-			if (extracted.exists()) {
-				if (extracted.delete()) LOG.info("Deleted old binary");
-				else LOG.info("Failed to delete old binary");
-			}
-		} else if (SDK_INT < 29) {
-			// The binary wasn't extracted at install time. Try to extract it
-			extractLibraryFromApk(libName, extracted);
-		} else {
-			// No point extracting the binary, we won't be allowed to execute it
-			throw new FileNotFoundException(lib.getAbsolutePath());
-		}
-	}
-
-	private void extractLibraryFromApk(String libName, File dest)
-			throws IOException {
-		File sourceDir = new File(app.getApplicationInfo().sourceDir);
-		if (sourceDir.isFile()) {
-			// Look for other APK files in the same directory, if we're allowed
-			File parent = sourceDir.getParentFile();
-			if (parent != null) sourceDir = parent;
-		}
-		List<String> libPaths = getSupportedLibraryPaths(libName);
-		for (File apk : findApkFiles(sourceDir)) {
-			ZipInputStream zin = new ZipInputStream(new FileInputStream(apk));
-			for (ZipEntry e = zin.getNextEntry(); e != null;
-					e = zin.getNextEntry()) {
-				if (libPaths.contains(e.getName())) {
-					if (LOG.isLoggable(INFO)) {
-						LOG.info("Extracting " + e.getName()
-								+ " from " + apk.getAbsolutePath());
-					}
-					extract(zin, dest); // Zip input stream will be closed
-					return;
-				}
-			}
-			zin.close();
-		}
-		throw new FileNotFoundException(libName);
-	}
-
-	/**
-	 * Returns all files with the extension .apk or .APK under the given root.
-	 */
-	private List<File> findApkFiles(File root) {
-		List<File> files = new ArrayList<>();
-		findApkFiles(root, files);
-		return files;
-	}
-
-	private void findApkFiles(File f, List<File> files) {
-		if (f.isFile() && f.getName().toLowerCase().endsWith(".apk")) {
-			files.add(f);
-		} else if (f.isDirectory()) {
-			File[] children = f.listFiles();
-			if (children != null) {
-				for (File child : children) findApkFiles(child, files);
-			}
-		}
-	}
-
-	/**
-	 * Returns the paths at which libraries with the given name would be found
-	 * inside an APK file, for all architectures supported by the device, in
-	 * order of preference.
-	 */
-	private List<String> getSupportedLibraryPaths(String libName) {
-		List<String> architectures = new ArrayList<>();
-		for (String abi : AndroidUtils.getSupportedArchitectures()) {
-			if (LIBRARY_ARCHITECTURES.contains(abi)) {
-				architectures.add("lib/" + abi + "/" + libName);
-			}
-		}
-		return architectures;
-	}
-}

bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/AndroidTorPluginFactory.java

@@ -2,9 +2,11 @@ package org.briarproject.bramble.plugin.tor;
 
 import android.app.Application;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.battery.BatteryManager;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.network.NetworkManager;
 import org.briarproject.bramble.api.plugin.Backoff;
@@ -13,12 +15,13 @@ import org.briarproject.bramble.api.plugin.PluginCallback;
 import org.briarproject.bramble.api.plugin.TorControlPort;
 import org.briarproject.bramble.api.plugin.TorDirectory;
 import org.briarproject.bramble.api.plugin.TorSocksPort;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.api.system.ResourceProvider;
 import org.briarproject.bramble.api.system.WakefulIoExecutor;
 import org.briarproject.nullsafety.NotNullByDefault;
+import org.briarproject.onionwrapper.AndroidTorWrapper;
+import org.briarproject.onionwrapper.CircumventionProvider;
+import org.briarproject.onionwrapper.LocationUtils;
+import org.briarproject.onionwrapper.TorWrapper;
 
 import java.io.File;
 import java.util.concurrent.Executor;
@@ -28,6 +31,7 @@ import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 import javax.net.SocketFactory;
 
+import static android.os.Build.VERSION.SDK_INT;
 import static org.briarproject.bramble.util.AndroidUtils.getSupportedArchitectures;
 
 @Immutable
@@ -39,13 +43,13 @@ public class AndroidTorPluginFactory extends TorPluginFactory {
 
 	@Inject
 	AndroidTorPluginFactory(@IoExecutor Executor ioExecutor,
+			@EventExecutor Executor eventExecutor,
 			@WakefulIoExecutor Executor wakefulIoExecutor,
 			NetworkManager networkManager,
 			LocationUtils locationUtils,
 			EventBus eventBus,
 			SocketFactory torSocketFactory,
 			BackoffFactory backoffFactory,
-			ResourceProvider resourceProvider,
 			CircumventionProvider circumventionProvider,
 			BatteryManager batteryManager,
 			Clock clock,
@@ -55,8 +59,8 @@ public class AndroidTorPluginFactory extends TorPluginFactory {
 			@TorControlPort int torControlPort,
 			Application app,
 			AndroidWakeLockManager wakeLockManager) {
-		super(ioExecutor, wakefulIoExecutor, networkManager, locationUtils,
-				eventBus, torSocketFactory, backoffFactory, resourceProvider,
+		super(ioExecutor, eventExecutor, wakefulIoExecutor, networkManager,
+				locationUtils, eventBus, torSocketFactory, backoffFactory,
 				circumventionProvider, batteryManager, clock, crypto,
 				torDirectory, torSocksPort, torControlPort);
 		this.app = app;
@@ -79,12 +83,18 @@ public class AndroidTorPluginFactory extends TorPluginFactory {
 	TorPlugin createPluginInstance(Backoff backoff,
 			TorRendezvousCrypto torRendezvousCrypto, PluginCallback callback,
 			String architecture) {
-		return new AndroidTorPlugin(ioExecutor,
-				wakefulIoExecutor, app, networkManager, locationUtils,
-				torSocketFactory, clock, resourceProvider,
-				circumventionProvider, batteryManager, wakeLockManager,
-				backoff, torRendezvousCrypto, callback, architecture,
-				MAX_LATENCY, MAX_IDLE_TIME, torDirectory, torSocksPort,
-				torControlPort);
+		TorWrapper tor = new AndroidTorWrapper(app, wakeLockManager,
+				ioExecutor, eventExecutor, architecture, torDirectory,
+				torSocksPort, torControlPort);
+		// Android versions 7.1 and newer can verify Let's Encrypt TLS certs
+		// signed with the IdentTrust DST Root X3 certificate. Older versions
+		// of Android consider the certificate to have expired at the end of
+		// September 2021.
+		boolean canVerifyLetsEncryptCerts = SDK_INT >= 25;
+		return new TorPlugin(ioExecutor, wakefulIoExecutor,
+				networkManager, locationUtils, torSocketFactory,
+				circumventionProvider, batteryManager, backoff,
+				torRendezvousCrypto, tor, callback, MAX_LATENCY,
+				MAX_IDLE_TIME, canVerifyLetsEncryptCerts);
 	}
 }

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidLocationUtils.java

@@ -1,72 +0,0 @@
-package org.briarproject.bramble.system;
-
-import android.annotation.SuppressLint;
-import android.app.Application;
-import android.content.Context;
-import android.telephony.TelephonyManager;
-import android.text.TextUtils;
-
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.util.Locale;
-import java.util.logging.Logger;
-
-import javax.inject.Inject;
-
-import static android.content.Context.TELEPHONY_SERVICE;
-
-@NotNullByDefault
-class AndroidLocationUtils implements LocationUtils {
-
-	private static final Logger LOG =
-			Logger.getLogger(AndroidLocationUtils.class.getName());
-
-	private final Context appContext;
-
-	@Inject
-	AndroidLocationUtils(Application app) {
-		appContext = app.getApplicationContext();
-	}
-
-	/**
-	 * This guesses the current country from the first of these sources that
-	 * succeeds (also in order of likelihood of being correct):
-	 *
-	 * <ul>
-	 * <li>Phone network. This works even when no SIM card is inserted, or a
-	 *     foreign SIM card is inserted.</li>
-	 * <li>SIM card. This is only an heuristic and assumes the user is not
-	 *     roaming.</li>
-	 * <li>User locale. This is an even worse heuristic.</li>
-	 * </ul>
-	 *
-	 * Note: this is very similar to <a href="https://android.googlesource.com/platform/frameworks/base/+/cd92588%5E/location/java/android/location/CountryDetector.java">
-	 * this API</a> except it seems that Google doesn't want us to use it for
-	 * some reason - both that class and {@code Context.COUNTRY_CODE} are
-	 * annotated {@code @hide}.
-	 */
-	@Override
-	@SuppressLint("DefaultLocale")
-	public String getCurrentCountry() {
-		String countryCode = getCountryFromPhoneNetwork();
-		if (!TextUtils.isEmpty(countryCode)) return countryCode.toUpperCase();
-		LOG.info("Falling back to SIM card country");
-		countryCode = getCountryFromSimCard();
-		if (!TextUtils.isEmpty(countryCode)) return countryCode.toUpperCase();
-		LOG.info("Falling back to user-defined locale");
-		return Locale.getDefault().getCountry();
-	}
-
-	private String getCountryFromPhoneNetwork() {
-		Object o = appContext.getSystemService(TELEPHONY_SERVICE);
-		TelephonyManager tm = (TelephonyManager) o;
-		return tm == null ? "" : tm.getNetworkCountryIso();
-	}
-
-	private String getCountryFromSimCard() {
-		Object o = appContext.getSystemService(TELEPHONY_SERVICE);
-		TelephonyManager tm = (TelephonyManager) o;
-		return tm == null ? "" : tm.getSimCountryIso();
-	}
-}

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSecureRandomProvider.java

@@ -31,8 +31,6 @@ import static android.provider.Settings.Secure.ANDROID_ID;
 @NotNullByDefault
 class AndroidSecureRandomProvider extends UnixSecureRandomProvider {
 
-	private static final int SEED_LENGTH = 32;
-
 	private final Context appContext;
 
 	@Inject
@@ -72,27 +70,6 @@ class AndroidSecureRandomProvider extends UnixSecureRandomProvider {
 		// Silence strict mode
 		StrictMode.ThreadPolicy tp = StrictMode.allowThreadDiskWrites();
 		super.writeSeed();
-		if (SDK_INT <= 18) applyOpenSslFix();
 		StrictMode.setThreadPolicy(tp);
 	}
-
-	// Based on https://android-developers.googleblog.com/2013/08/some-securerandom-thoughts.html
-	private void applyOpenSslFix() {
-		byte[] seed = new UnixSecureRandomSpi().engineGenerateSeed(
-				SEED_LENGTH);
-		try {
-			// Seed the OpenSSL PRNG
-			Class.forName("org.apache.harmony.xnet.provider.jsse.NativeCrypto")
-					.getMethod("RAND_seed", byte[].class)
-					.invoke(null, (Object) seed);
-			// Mix the output of the Linux PRNG into the OpenSSL PRNG
-			int bytesRead = (Integer) Class.forName(
-							"org.apache.harmony.xnet.provider.jsse.NativeCrypto")
-					.getMethod("RAND_load_file", String.class, long.class)
-					.invoke(null, "/dev/urandom", 1024);
-			if (bytesRead != 1024) throw new IOException();
-		} catch (Exception e) {
-			throw new SecurityException(e);
-		}
-	}
 }

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSystemModule.java

@@ -1,12 +1,14 @@
 package org.briarproject.bramble.system;
 
+import android.app.Application;
+
 import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.system.AndroidExecutor;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
-import org.briarproject.bramble.api.system.LocationUtils;
 import org.briarproject.bramble.api.system.ResourceProvider;
 import org.briarproject.bramble.api.system.SecureRandomProvider;
+import org.briarproject.onionwrapper.AndroidLocationUtilsFactory;
+import org.briarproject.onionwrapper.LocationUtils;
 
 import java.util.concurrent.Executor;
 import java.util.concurrent.RejectedExecutionHandler;
@@ -46,8 +48,9 @@ public class AndroidSystemModule {
 	}
 
 	@Provides
-	LocationUtils provideLocationUtils(AndroidLocationUtils locationUtils) {
-		return locationUtils;
+	@Singleton
+	LocationUtils provideLocationUtils(Application app) {
+		return AndroidLocationUtilsFactory.createAndroidLocationUtils(app);
 	}
 
 	@Provides
@@ -69,11 +72,4 @@ public class AndroidSystemModule {
 	ResourceProvider provideResourceProvider(AndroidResourceProvider provider) {
 		return provider;
 	}
-
-	@Provides
-	@Singleton
-	AndroidWakeLockManager provideWakeLockManager(
-			AndroidWakeLockManagerImpl wakeLockManager) {
-		return wakeLockManager;
-	}
 }

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidTaskScheduler.java

@@ -8,10 +8,10 @@ import android.content.Intent;
 import android.os.Process;
 import android.os.SystemClock;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.Cancellable;
 import org.briarproject.bramble.api.lifecycle.Service;
 import org.briarproject.bramble.api.system.AlarmListener;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.TaskScheduler;
 import org.briarproject.bramble.api.system.Wakeful;
 import org.briarproject.nullsafety.NotNullByDefault;

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidTaskSchedulerModule.java

@@ -2,9 +2,9 @@ package org.briarproject.bramble.system;
 
 import android.app.Application;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.system.AlarmListener;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.TaskScheduler;
 
 import java.util.concurrent.ScheduledExecutorService;

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockImpl.java

@@ -1,74 +0,0 @@
-package org.briarproject.bramble.system;
-
-import org.briarproject.bramble.api.system.AndroidWakeLock;
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.util.concurrent.atomic.AtomicInteger;
-import java.util.logging.Logger;
-
-import javax.annotation.concurrent.GuardedBy;
-import javax.annotation.concurrent.ThreadSafe;
-
-import static java.util.logging.Level.FINE;
-import static java.util.logging.Logger.getLogger;
-
-/**
- * A wrapper around a {@link SharedWakeLock} that provides the more convenient
- * semantics of {@link AndroidWakeLock} (i.e. calls to acquire() and release()
- * don't need to be balanced).
- */
-@ThreadSafe
-@NotNullByDefault
-class AndroidWakeLockImpl implements AndroidWakeLock {
-
-	private static final Logger LOG =
-			getLogger(AndroidWakeLockImpl.class.getName());
-
-	private static final AtomicInteger INSTANCE_ID = new AtomicInteger(0);
-
-	private final SharedWakeLock sharedWakeLock;
-	private final String tag;
-
-	private final Object lock = new Object();
-	@GuardedBy("lock")
-	private boolean held = false;
-
-	AndroidWakeLockImpl(SharedWakeLock sharedWakeLock, String tag) {
-		this.sharedWakeLock = sharedWakeLock;
-		this.tag = tag + "_" + INSTANCE_ID.getAndIncrement();
-	}
-
-	@Override
-	public void acquire() {
-		synchronized (lock) {
-			if (held) {
-				if (LOG.isLoggable(FINE)) {
-					LOG.fine(tag + " already acquired");
-				}
-			} else {
-				if (LOG.isLoggable(FINE)) {
-					LOG.fine(tag + " acquiring shared wake lock");
-				}
-				held = true;
-				sharedWakeLock.acquire();
-			}
-		}
-	}
-
-	@Override
-	public void release() {
-		synchronized (lock) {
-			if (held) {
-				if (LOG.isLoggable(FINE)) {
-					LOG.fine(tag + " releasing shared wake lock");
-				}
-				held = false;
-				sharedWakeLock.release();
-			} else {
-				if (LOG.isLoggable(FINE)) {
-					LOG.fine(tag + " already released");
-				}
-			}
-		}
-	}
-}

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockManagerImpl.java

@@ -1,125 +0,0 @@
-package org.briarproject.bramble.system;
-
-import android.app.Application;
-import android.content.Context;
-import android.content.pm.PackageManager;
-import android.os.PowerManager;
-
-import org.briarproject.bramble.api.system.AndroidWakeLock;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.util.concurrent.Executor;
-import java.util.concurrent.ScheduledExecutorService;
-
-import javax.inject.Inject;
-
-import static android.content.Context.POWER_SERVICE;
-import static android.os.PowerManager.PARTIAL_WAKE_LOCK;
-import static java.util.concurrent.TimeUnit.MINUTES;
-import static java.util.concurrent.TimeUnit.SECONDS;
-import static org.briarproject.nullsafety.NullSafety.requireNonNull;
-
-@NotNullByDefault
-class AndroidWakeLockManagerImpl implements AndroidWakeLockManager {
-
-	/**
-	 * How often to replace the wake lock.
-	 */
-	private static final long LOCK_DURATION_MS = MINUTES.toMillis(1);
-
-	/**
-	 * Automatically release the lock this many milliseconds after it's due
-	 * to have been replaced and released.
-	 */
-	private static final long SAFETY_MARGIN_MS = SECONDS.toMillis(30);
-
-	private final SharedWakeLock sharedWakeLock;
-
-	@Inject
-	AndroidWakeLockManagerImpl(Application app,
-			ScheduledExecutorService scheduledExecutorService) {
-		PowerManager powerManager = (PowerManager)
-				requireNonNull(app.getSystemService(POWER_SERVICE));
-		String tag = getWakeLockTag(app);
-		sharedWakeLock = new RenewableWakeLock(powerManager,
-				scheduledExecutorService, PARTIAL_WAKE_LOCK, tag,
-				LOCK_DURATION_MS, SAFETY_MARGIN_MS);
-	}
-
-	@Override
-	public AndroidWakeLock createWakeLock(String tag) {
-		return new AndroidWakeLockImpl(sharedWakeLock, tag);
-	}
-
-	@Override
-	public void runWakefully(Runnable r, String tag) {
-		AndroidWakeLock wakeLock = createWakeLock(tag);
-		wakeLock.acquire();
-		try {
-			r.run();
-		} finally {
-			wakeLock.release();
-		}
-	}
-
-	@Override
-	public void executeWakefully(Runnable r, Executor executor, String tag) {
-		AndroidWakeLock wakeLock = createWakeLock(tag);
-		wakeLock.acquire();
-		try {
-			executor.execute(() -> {
-				try {
-					r.run();
-				} finally {
-					// Release the wake lock if the task throws an exception
-					wakeLock.release();
-				}
-			});
-		} catch (Exception e) {
-			// Release the wake lock if the executor throws an exception when
-			// we submit the task (in which case the release() call above won't
-			// happen)
-			wakeLock.release();
-			throw e;
-		}
-	}
-
-	@Override
-	public void executeWakefully(Runnable r, String tag) {
-		AndroidWakeLock wakeLock = createWakeLock(tag);
-		wakeLock.acquire();
-		try {
-			new Thread(() -> {
-				try {
-					r.run();
-				} finally {
-					wakeLock.release();
-				}
-			}).start();
-		} catch (Exception e) {
-			wakeLock.release();
-			throw e;
-		}
-	}
-
-	private String getWakeLockTag(Context ctx) {
-		PackageManager pm = ctx.getPackageManager();
-		if (isInstalled(pm, "com.huawei.powergenie")) {
-			return "LocationManagerService";
-		} else if (isInstalled(pm, "com.evenwell.PowerMonitor")) {
-			return "AudioIn";
-		}
-		return ctx.getPackageName();
-	}
-
-	private boolean isInstalled(PackageManager pm, String packageName) {
-		try {
-			pm.getPackageInfo(packageName, 0);
-			return true;
-		} catch (PackageManager.NameNotFoundException e) {
-			return false;
-		}
-	}
-
-}

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakeLockModule.java

@@ -0,0 +1,25 @@
+package org.briarproject.bramble.system;
+
+import android.app.Application;
+
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManagerFactory;
+
+import java.util.concurrent.ScheduledExecutorService;
+
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class AndroidWakeLockModule {
+
+	@Provides
+	@Singleton
+	AndroidWakeLockManager provideWakeLockManager(Application app,
+			ScheduledExecutorService scheduledExecutorService) {
+		return AndroidWakeLockManagerFactory.createAndroidWakeLockManager(app,
+				scheduledExecutorService);
+	}
+}

bramble-android/src/main/java/org/briarproject/bramble/system/AndroidWakefulIoExecutorModule.java

@@ -1,7 +1,7 @@
 package org.briarproject.bramble.system;
 
+import org.briarproject.android.dontkillmelib.wakelock.AndroidWakeLockManager;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.bramble.api.system.AndroidWakeLockManager;
 import org.briarproject.bramble.api.system.WakefulIoExecutor;
 
 import java.util.concurrent.Executor;

bramble-android/src/main/java/org/briarproject/bramble/system/RenewableWakeLock.java

@@ -1,130 +0,0 @@
-package org.briarproject.bramble.system;
-
-import android.os.PowerManager;
-import android.os.PowerManager.WakeLock;
-
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.util.concurrent.Future;
-import java.util.concurrent.ScheduledExecutorService;
-import java.util.logging.Logger;
-
-import javax.annotation.Nullable;
-import javax.annotation.concurrent.GuardedBy;
-import javax.annotation.concurrent.ThreadSafe;
-
-import static java.util.concurrent.TimeUnit.MILLISECONDS;
-import static java.util.logging.Level.FINE;
-import static java.util.logging.Level.INFO;
-import static java.util.logging.Level.WARNING;
-import static java.util.logging.Logger.getLogger;
-import static org.briarproject.nullsafety.NullSafety.requireNonNull;
-
-@ThreadSafe
-@NotNullByDefault
-class RenewableWakeLock implements SharedWakeLock {
-
-	private static final Logger LOG =
-			getLogger(RenewableWakeLock.class.getName());
-
-	private final PowerManager powerManager;
-	private final ScheduledExecutorService scheduledExecutorService;
-	private final int levelAndFlags;
-	private final String tag;
-	private final long durationMs, safetyMarginMs;
-
-	private final Object lock = new Object();
-	@GuardedBy("lock")
-	@Nullable
-	private WakeLock wakeLock;
-	@GuardedBy("lock")
-	@Nullable
-	private Future<?> future;
-	@GuardedBy("lock")
-	private int refCount = 0;
-	@GuardedBy("lock")
-	private long acquired = 0;
-
-	RenewableWakeLock(PowerManager powerManager,
-			ScheduledExecutorService scheduledExecutorService,
-			int levelAndFlags,
-			String tag,
-			long durationMs,
-			long safetyMarginMs) {
-		this.powerManager = powerManager;
-		this.scheduledExecutorService = scheduledExecutorService;
-		this.levelAndFlags = levelAndFlags;
-		this.tag = tag;
-		this.durationMs = durationMs;
-		this.safetyMarginMs = safetyMarginMs;
-	}
-
-	@Override
-	public void acquire() {
-		synchronized (lock) {
-			refCount++;
-			if (refCount == 1) {
-				if (LOG.isLoggable(INFO)) {
-					LOG.info("Acquiring wake lock " + tag);
-				}
-				wakeLock = powerManager.newWakeLock(levelAndFlags, tag);
-				// We do our own reference counting so we can replace the lock
-				// TODO: Check whether using a ref-counted wake lock affects
-				//  power management apps
-				wakeLock.setReferenceCounted(false);
-				wakeLock.acquire(durationMs + safetyMarginMs);
-				future = scheduledExecutorService.schedule(this::renew,
-						durationMs, MILLISECONDS);
-				acquired = android.os.SystemClock.elapsedRealtime();
-			} else if (LOG.isLoggable(FINE)) {
-				LOG.fine("Wake lock " + tag + " has " + refCount + " holders");
-			}
-		}
-	}
-
-	private void renew() {
-		if (LOG.isLoggable(INFO)) LOG.info("Renewing wake lock " + tag);
-		synchronized (lock) {
-			if (wakeLock == null) {
-				LOG.info("Already released");
-				return;
-			}
-			if (LOG.isLoggable(FINE)) {
-				LOG.fine("Wake lock " + tag + " has " + refCount + " holders");
-			}
-			long now = android.os.SystemClock.elapsedRealtime();
-			long expiry = acquired + durationMs + safetyMarginMs;
-			if (now > expiry && LOG.isLoggable(WARNING)) {
-				LOG.warning("Wake lock expired " + (now - expiry) + " ms ago");
-			}
-			WakeLock oldWakeLock = wakeLock;
-			wakeLock = powerManager.newWakeLock(levelAndFlags, tag);
-			wakeLock.setReferenceCounted(false);
-			wakeLock.acquire(durationMs + safetyMarginMs);
-			oldWakeLock.release();
-			future = scheduledExecutorService.schedule(this::renew, durationMs,
-					MILLISECONDS);
-			acquired = now;
-		}
-	}
-
-	@Override
-	public void release() {
-		synchronized (lock) {
-			refCount--;
-			if (refCount == 0) {
-				if (LOG.isLoggable(INFO)) {
-					LOG.info("Releasing wake lock " + tag);
-				}
-				requireNonNull(future).cancel(false);
-				future = null;
-				requireNonNull(wakeLock).release();
-				wakeLock = null;
-				acquired = 0;
-			} else if (LOG.isLoggable(FINE)) {
-				LOG.fine("Wake lock " + tag + " has " + refCount + " holders");
-			}
-		}
-	}
-}
-

bramble-android/src/main/java/org/briarproject/bramble/system/SharedWakeLock.java

@@ -1,22 +0,0 @@
-package org.briarproject.bramble.system;
-
-import org.briarproject.bramble.api.system.AndroidWakeLock;
-import org.briarproject.nullsafety.NotNullByDefault;
-
-@NotNullByDefault
-interface SharedWakeLock {
-
-	/**
-	 * Acquires the wake lock. This increments the wake lock's reference count,
-	 * so unlike {@link AndroidWakeLock#acquire()} every call to this method
-	 * must be followed by a balancing call to {@link #release()}.
-	 */
-	void acquire();
-
-	/**
-	 * Releases the wake lock. This decrements the wake lock's reference count,
-	 * so unlike {@link AndroidWakeLock#release()} every call to this method
-	 * must follow a balancing call to {@link #acquire()}.
-	 */
-	void release();
-}

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

@@ -11,14 +11,10 @@ import org.briarproject.bramble.api.Pair;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.File;
-import java.io.IOException;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
-import java.util.ArrayList;
 import java.util.Collection;
-import java.util.List;
-import java.util.Scanner;
 
 import javax.annotation.Nullable;
 
@@ -29,7 +25,6 @@ import static android.content.pm.PackageManager.PERMISSION_GRANTED;
 import static android.os.Build.VERSION.SDK_INT;
 import static android.os.Process.myPid;
 import static android.os.Process.myUid;
-import static java.lang.Runtime.getRuntime;
 import static java.util.Arrays.asList;
 import static org.briarproject.nullsafety.NullSafety.requireNonNull;
 
@@ -43,14 +38,7 @@ public class AndroidUtils {
 	private static final String STORED_LOGCAT = "dev-logcat";
 
 	public static Collection<String> getSupportedArchitectures() {
-		List<String> abis = new ArrayList<>();
-		if (SDK_INT >= 21) {
-			abis.addAll(asList(Build.SUPPORTED_ABIS));
-		} else {
-			abis.add(Build.CPU_ABI);
-			if (Build.CPU_ABI2 != null) abis.add(Build.CPU_ABI2);
-		}
-		return abis;
+		return asList(Build.SUPPORTED_ABIS);
 	}
 
 	public static boolean hasBtConnectPermission(Context ctx) {
@@ -65,6 +53,9 @@ public class AndroidUtils {
 
 	public static Pair<String, String> getBluetoothAddressAndMethod(Context ctx,
 			BluetoothAdapter adapter) {
+		// If we don't have permission to access the adapter's address, let
+		// the caller know we can't find it
+		if (!hasBtConnectPermission(ctx)) return new Pair<>("", "");
 		// Return the adapter's address if it's valid and not fake
 		@SuppressLint("HardwareIds")
 		String address = adapter.getAddress();
@@ -72,10 +63,17 @@ public class AndroidUtils {
 			return new Pair<>(address, "adapter");
 		}
 		// Return the address from settings if it's valid and not fake
-		address = Settings.Secure.getString(ctx.getContentResolver(),
-				"bluetooth_address");
-		if (isValidBluetoothAddress(address)) {
-			return new Pair<>(address, "settings");
+		if (SDK_INT < 33) {
+			try {
+				address = Settings.Secure.getString(ctx.getContentResolver(),
+						"bluetooth_address");
+				if (isValidBluetoothAddress(address)) {
+					return new Pair<>(address, "settings");
+				}
+			} catch (SecurityException e) {
+				// Some custom ROMs throw this exception on SDK_INT < 33.
+				// Fall through
+			}
 		}
 		// Try to get the address via reflection
 		address = getBluetoothAddressByReflection(adapter);
@@ -133,19 +131,6 @@ public class AndroidUtils {
 		return new String[] {"image/jpeg", "image/png", "image/gif"};
 	}
 
-	@Nullable
-	public static String getSystemProperty(String propName) {
-		try {
-			Process p = getRuntime().exec("getprop " + propName);
-			Scanner s = new Scanner(p.getInputStream());
-			String line = s.nextLine();
-			s.close();
-			return line;
-		} catch (SecurityException | IOException e) {
-			return null;
-		}
-	}
-
 	public static boolean isUiThread() {
 		return Looper.myLooper() == Looper.getMainLooper();
 	}

bramble-android/src/test/java/org/briarproject/bramble/account/AndroidAccountManagerTest.java

@@ -87,6 +87,10 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 		File potatoFile = new File(potatoDir, "file");
 		File filesDir = new File(testDir, "filesDir");
 		File externalCacheDir = new File(testDir, "externalCacheDir");
+		File externalCacheDir1 = new File(testDir, "externalCacheDir1");
+		File externalCacheDir2 = new File(testDir, "externalCacheDir2");
+		File externalMediaDir1 = new File(testDir, "externalMediaDir1");
+		File externalMediaDir2 = new File(testDir, "externalMediaDir2");
 
 		context.checking(new Expectations() {{
 			oneOf(prefs).edit();
@@ -109,6 +113,12 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 			will(returnValue(cacheDir));
 			oneOf(app).getExternalCacheDir();
 			will(returnValue(externalCacheDir));
+			oneOf(app).getExternalCacheDirs();
+			will(returnValue(
+					new File[] {externalCacheDir1, externalCacheDir2}));
+			oneOf(app).getExternalMediaDirs();
+			will(returnValue(
+					new File[] {externalMediaDir1, externalMediaDir2}));
 		}});
 
 		assertTrue(dbDir.mkdirs());
@@ -125,6 +135,10 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 		assertTrue(potatoFile.createNewFile());
 		assertTrue(filesDir.mkdirs());
 		assertTrue(externalCacheDir.mkdirs());
+		assertTrue(externalCacheDir1.mkdirs());
+		assertTrue(externalCacheDir2.mkdirs());
+		assertTrue(externalMediaDir1.mkdirs());
+		assertTrue(externalMediaDir2.mkdirs());
 
 		accountManager.deleteAccount();
 
@@ -142,6 +156,10 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 		assertFalse(potatoFile.exists());
 		assertFalse(filesDir.exists());
 		assertFalse(externalCacheDir.exists());
+		assertFalse(externalCacheDir1.exists());
+		assertFalse(externalCacheDir2.exists());
+		assertFalse(externalMediaDir1.exists());
+		assertFalse(externalMediaDir2.exists());
 	}
 
 	@After

bramble-android/witness.gradle

@@ -1,59 +1,67 @@
 dependencyVerification {
     verify = [
-        'androidx.annotation:annotation:1.5.0:annotation-1.5.0.jar:261fb7c0210858500bab66d34354972a75166ab4182add283780b05513d6ec4a',
-        'cglib:cglib:3.2.8:cglib-3.2.8.jar:3f64de999ecc5595dc84ca8ff0879d8a34c8623f9ef3c517a53ed59023fcb9db',
-        'com.google.code.findbugs:annotations:3.0.1:annotations-3.0.1.jar:6b47ff0a6de0ce17cbedc3abb0828ca5bce3009d53ea47b3723ff023c4742f79',
-        'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
-        'com.google.dagger:dagger-compiler:2.43.2:dagger-compiler-2.43.2.jar:298c020ee6ed2f4cc651ebbfdb7f8de329b07c44b618d65be117846a850e2a03',
-        'com.google.dagger:dagger-producers:2.43.2:dagger-producers-2.43.2.jar:e7f5d9ffc85d48a49c8e22e02833d418f7ccad5d7512f529964db5127ab915ff',
-        'com.google.dagger:dagger-spi:2.43.2:dagger-spi-2.43.2.jar:3bae8d9dadeaaa5927da6f094389a560c12c05fec3d2711d2fa79292c7a7d7ad',
-        'com.google.dagger:dagger:2.43.2:dagger-2.43.2.jar:c89681f7cbbf8c527bf4ac2748515d617fdb54a1d425c08d914fdc28192b5fe4',
-        'com.google.devtools.ksp:symbol-processing-api:1.7.0-1.0.6:symbol-processing-api-1.7.0-1.0.6.jar:adc29417be5ca9ff42118105fea4e36d9ef44987abfc41432309371a60198941',
-        'com.google.errorprone:error_prone_annotations:2.7.1:error_prone_annotations-2.7.1.jar:cd5257c08a246cf8628817ae71cb822be192ef91f6881ca4a3fcff4f1de1cff3',
-        'com.google.errorprone:javac-shaded:9-dev-r4023-3:javac-shaded-9-dev-r4023-3.jar:65bfccf60986c47fbc17c9ebab0be626afc41741e0a6ec7109e0768817a36f30',
-        'com.google.googlejavaformat:google-java-format:1.5:google-java-format-1.5.jar:aa19ad7850fb85178aa22f2fddb163b84d6ce4d0035872f30d4408195ca1144e',
-        'com.google.guava:failureaccess:1.0.1:failureaccess-1.0.1.jar:a171ee4c734dd2da837e4b16be9df4661afab72a41adaf31eb84dfdaf936ca26',
-        'com.google.guava:guava:31.0.1-jre:guava-31.0.1-jre.jar:d5be94d65e87bd219fb3193ad1517baa55a3b88fc91d21cf735826ab5af087b9',
-        'com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava:listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:b372a037d4230aa57fbeffdef30fd6123f9c0c2db85d0aced00c91b974f33f99',
-        'com.google.j2objc:j2objc-annotations:1.3:j2objc-annotations-1.3.jar:21af30c92267bd6122c0e0b4d20cccb6641a37eaf956c6540ec471d584e64a7b',
-        'com.squareup:javapoet:1.13.0:javapoet-1.13.0.jar:4c7517e848a71b36d069d12bb3bf46a70fd4cda3105d822b0ed2e19c00b69291',
-        'javax.annotation:jsr250-api:1.0:jsr250-api-1.0.jar:a1a922d0d9b6d183ed3800dfac01d1e1eb159f0e8c6f94736931c1def54a941f',
-        'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
-        'junit:junit:4.13.2:junit-4.13.2.jar:8e495b634469d64fb8acfa3495a065cbacc8a0fff55ce1e31007be4c16dc57d3',
-        'net.bytebuddy:byte-buddy:1.9.12:byte-buddy-1.9.12.jar:3688c3d434bebc3edc5516296a2ed0f47b65e451071b4afecad84f902f0efc11',
-        'net.jcip:jcip-annotations:1.0:jcip-annotations-1.0.jar:be5805392060c71474bf6c9a67a099471274d30b83eef84bfc4e0889a4f1dcc0',
-        'net.ltgt.gradle.incap:incap:0.2:incap-0.2.jar:b625b9806b0f1e4bc7a2e3457119488de3cd57ea20feedd513db070a573a4ffd',
-        'org.apache-extras.beanshell:bsh:2.0b6:bsh-2.0b6.jar:a17955976070c0573235ee662f2794a78082758b61accffce8d3f8aedcd91047',
-        'org.briarproject:obfs4proxy-android:0.0.14-tor1:obfs4proxy-android-0.0.14-tor1.jar:8b08068778b133484b17956d8f7a7710739c33f671a26a68156f4d34e6f28c30',
-        'org.briarproject:snowflake-android:2.3.1:snowflake-android-2.3.1.jar:1f83c9a070f87b7074af13627709a8b5aced5460104be7166af736b1bb73c293',
-        'org.briarproject:tor-android:0.4.5.14:tor-android-0.4.5.14.jar:7cf1beaa6c1db51fc8fac263aba9624ef289c3db29772509efcbc59f7057330a',
-        'org.checkerframework:checker-compat-qual:2.5.5:checker-compat-qual-2.5.5.jar:11d134b245e9cacc474514d2d66b5b8618f8039a1465cdc55bbc0b34e0008b7a',
-        'org.checkerframework:checker-qual:3.12.0:checker-qual-3.12.0.jar:ff10785ac2a357ec5de9c293cb982a2cbb605c0309ea4cc1cb9b9bc6dbe7f3cb',
-        'org.hamcrest:hamcrest-core:2.1:hamcrest-core-2.1.jar:e09109e54a289d88506b9bfec987ddd199f4217c9464132668351b9a4f00bee9',
-        'org.hamcrest:hamcrest-library:2.1:hamcrest-library-2.1.jar:b7e2b6895b3b679f0e47b6380fda391b225e9b78505db9d8bdde8d3cc8d52a21',
-        'org.hamcrest:hamcrest:2.1:hamcrest-2.1.jar:ba93b2e3a562322ba432f0a1b53addcc55cb188253319a020ed77f824e692050',
-        'org.jacoco:org.jacoco.agent:0.8.7:org.jacoco.agent-0.8.7.jar:9cbcc986e0fbe821a78ff1f8f7d5216f200e5eb124e7f6837d1dc4a77b28b143',
-        'org.jacoco:org.jacoco.ant:0.8.7:org.jacoco.ant-0.8.7.jar:97ca96a382c3f23a44d8eb4c4e6c3742a30cb8005774a76ced0fc4806ce49605',
-        'org.jacoco:org.jacoco.core:0.8.7:org.jacoco.core-0.8.7.jar:ad7739b5fb5969aa1a8aead3d74ed54dc82ed012f1f10f336bd1b96e71c1a13c',
-        'org.jacoco:org.jacoco.report:0.8.7:org.jacoco.report-0.8.7.jar:cc89258623700a6c932592153cb528785876b6da183d5431f97efbba6f020e5b',
-        'org.jetbrains.kotlin:kotlin-stdlib-common:1.7.0:kotlin-stdlib-common-1.7.0.jar:59c6ff64fe9a6604afce03e8aaa75f83586c6030ac71fb0b34ee7cdefed3618f',
-        'org.jetbrains.kotlin:kotlin-stdlib-common:1.7.10:kotlin-stdlib-common-1.7.10.jar:19f102efe9629f8eabc63853ad15c533e47c47f91fca09285c5bde86e59f91d4',
-        'org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.0:kotlin-stdlib-jdk7-1.7.0.jar:07e91be9b2ca20672d2bdb7e181b766e73453a2da13492b5ddaee8fa47aea239',
-        'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.0:kotlin-stdlib-jdk8-1.7.0.jar:cf058e11db1dfc9944680c8c61b95ac689aaaa8a3eb30bced028100f038f030b',
-        'org.jetbrains.kotlin:kotlin-stdlib:1.7.0:kotlin-stdlib-1.7.0.jar:aa88e9625577957f3249a46cb6e166ee09b369e600f7a11d148d16b0a6d87f05',
-        'org.jetbrains.kotlin:kotlin-stdlib:1.7.10:kotlin-stdlib-1.7.10.jar:e771fe74250a943e8f6346713201ff1d8cb95c3a5d1a91a22b65a9e04f6a8901',
-        'org.jetbrains.kotlinx:kotlinx-metadata-jvm:0.5.0:kotlinx-metadata-jvm-0.5.0.jar:ca063a96639b08b9eaa0de4d65e899480740a6efbe28ab9a8681a2ced03055a4',
-        'org.jetbrains:annotations:13.0:annotations-13.0.jar:ace2a10dc8e2d5fd34925ecac03e4988b2c0f851650c94b8cef49ba1bd111478',
-        'org.jmock:jmock-imposters:2.12.0:jmock-imposters-2.12.0.jar:3b836269745a137c9b2347e8d7c2104845b126ef04f012d6bfd94f1a7dea7b09',
-        'org.jmock:jmock-junit4:2.12.0:jmock-junit4-2.12.0.jar:3233062fc889637c151a24f1ee086bad04321ab7d8264fef279daff0fa27205b',
-        'org.jmock:jmock-legacy:2.12.0:jmock-legacy-2.12.0.jar:dea3a9cca653d082e2fe7e40232e982fe03a9984c7d67ceff24f3e03fe580dcd',
-        'org.jmock:jmock-testjar:2.12.0:jmock-testjar-2.12.0.jar:efefbcf6cd294d0e29f0c46eb2a3380d4ca4e1763ff719c69e2f2ac62f564a04',
-        'org.jmock:jmock:2.12.0:jmock-2.12.0.jar:266d07314c0cd343c46ff8a55601272de8cf406807caf55e6f313295f83d10be',
-        'org.objenesis:objenesis:3.0.1:objenesis-3.0.1.jar:7a8ff780b9ff48415d7c705f60030b0acaa616e7f823c98eede3b63508d4e984',
-        'org.ow2.asm:asm-analysis:9.1:asm-analysis-9.1.jar:81a88041b1b8beda5a8a99646098046c48709538270c49def68abff25ac3be34',
-        'org.ow2.asm:asm-commons:9.1:asm-commons-9.1.jar:afcb26dc1fc12c0c4a99ada670908dd82e18dfc488caf5ee92546996b470c00c',
-        'org.ow2.asm:asm-tree:9.1:asm-tree-9.1.jar:fd00afa49e9595d7646205b09cecb4a776a8ff0ba06f2d59b8f7bf9c704b4a73',
-        'org.ow2.asm:asm:7.1:asm-7.1.jar:4ab2fa2b6d2cc9ccb1eaa05ea329c407b47b13ed2915f62f8c4b8cc96258d4de',
-        'org.ow2.asm:asm:9.1:asm-9.1.jar:cda4de455fab48ff0bcb7c48b4639447d4de859a7afc30a094a986f0936beba2',
+            'androidx.annotation:annotation:1.5.0:annotation-1.5.0.jar:261fb7c0210858500bab66d34354972a75166ab4182add283780b05513d6ec4a',
+            'cglib:cglib:3.2.8:cglib-3.2.8.jar:3f64de999ecc5595dc84ca8ff0879d8a34c8623f9ef3c517a53ed59023fcb9db',
+            'com.google.code.findbugs:annotations:3.0.1:annotations-3.0.1.jar:6b47ff0a6de0ce17cbedc3abb0828ca5bce3009d53ea47b3723ff023c4742f79',
+            'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
+            'com.google.dagger:dagger-compiler:2.45:dagger-compiler-2.45.jar:5617dfb994537dba5b41f3744a6dd13ec3cd99789c065e0d5c6fa9f21cf7ca25',
+            'com.google.dagger:dagger-producers:2.45:dagger-producers-2.45.jar:a05abb4c3ccf6bb0f056bdcb5ef973898ecf172952ab5948a824aeea6c86ecaa',
+            'com.google.dagger:dagger-spi:2.45:dagger-spi-2.45.jar:7cd6f0b09d88e64a9c97bc80e544ab8ac8fdee9301754413585a74cf64222b27',
+            'com.google.dagger:dagger:2.45:dagger-2.45.jar:f011cae7d2c0fb7ea17c34e05bc10e768b1081a5892ad019cf1fdb0e125c49c1',
+            'com.google.devtools.ksp:symbol-processing-api:1.7.0-1.0.6:symbol-processing-api-1.7.0-1.0.6.jar:adc29417be5ca9ff42118105fea4e36d9ef44987abfc41432309371a60198941',
+            'com.google.errorprone:error_prone_annotations:2.7.1:error_prone_annotations-2.7.1.jar:cd5257c08a246cf8628817ae71cb822be192ef91f6881ca4a3fcff4f1de1cff3',
+            'com.google.errorprone:javac-shaded:9-dev-r4023-3:javac-shaded-9-dev-r4023-3.jar:65bfccf60986c47fbc17c9ebab0be626afc41741e0a6ec7109e0768817a36f30',
+            'com.google.googlejavaformat:google-java-format:1.5:google-java-format-1.5.jar:aa19ad7850fb85178aa22f2fddb163b84d6ce4d0035872f30d4408195ca1144e',
+            'com.google.guava:failureaccess:1.0.1:failureaccess-1.0.1.jar:a171ee4c734dd2da837e4b16be9df4661afab72a41adaf31eb84dfdaf936ca26',
+            'com.google.guava:guava:31.0.1-jre:guava-31.0.1-jre.jar:d5be94d65e87bd219fb3193ad1517baa55a3b88fc91d21cf735826ab5af087b9',
+            'com.google.guava:listenablefuture:9999.0-empty-to-avoid-conflict-with-guava:listenablefuture-9999.0-empty-to-avoid-conflict-with-guava.jar:b372a037d4230aa57fbeffdef30fd6123f9c0c2db85d0aced00c91b974f33f99',
+            'com.google.j2objc:j2objc-annotations:1.3:j2objc-annotations-1.3.jar:21af30c92267bd6122c0e0b4d20cccb6641a37eaf956c6540ec471d584e64a7b',
+            'com.squareup:javapoet:1.13.0:javapoet-1.13.0.jar:4c7517e848a71b36d069d12bb3bf46a70fd4cda3105d822b0ed2e19c00b69291',
+            'com.squareup:kotlinpoet:1.11.0:kotlinpoet-1.11.0.jar:2887ada1ca03dd83baa2758640d87e840d1907564db0ef88d2289c868a980492',
+            'javax.annotation:jsr250-api:1.0:jsr250-api-1.0.jar:a1a922d0d9b6d183ed3800dfac01d1e1eb159f0e8c6f94736931c1def54a941f',
+            'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
+            'junit:junit:4.13.2:junit-4.13.2.jar:8e495b634469d64fb8acfa3495a065cbacc8a0fff55ce1e31007be4c16dc57d3',
+            'net.bytebuddy:byte-buddy:1.9.12:byte-buddy-1.9.12.jar:3688c3d434bebc3edc5516296a2ed0f47b65e451071b4afecad84f902f0efc11',
+            'net.jcip:jcip-annotations:1.0:jcip-annotations-1.0.jar:be5805392060c71474bf6c9a67a099471274d30b83eef84bfc4e0889a4f1dcc0',
+            'net.ltgt.gradle.incap:incap:0.2:incap-0.2.jar:b625b9806b0f1e4bc7a2e3457119488de3cd57ea20feedd513db070a573a4ffd',
+            'org.apache-extras.beanshell:bsh:2.0b6:bsh-2.0b6.jar:a17955976070c0573235ee662f2794a78082758b61accffce8d3f8aedcd91047',
+            'org.briarproject:dont-kill-me-lib:0.2.7:dont-kill-me-lib-0.2.7.aar:8a9540941fd927e1c127096a7a9b4aa61ce2f2965d2e24f849be92f9e57213c4',
+            'org.briarproject:jtorctl:0.5:jtorctl-0.5.jar:43f8c7d390169772b9a2c82ab806c8414c136a2a8636c555e22754bb7260793b',
+            'org.briarproject:null-safety:0.1:null-safety-0.1.jar:161760de5e838cb982bafa973df820675d4397098e9a91637a36a306d43ba011',
+            'org.briarproject:obfs4proxy-android:0.0.14-tor2:obfs4proxy-android-0.0.14-tor2.jar:a0a93770d6760ce57d9dbd31cc7177687374e00c3361dac22ab75e3b6e0f289e',
+            'org.briarproject:onionwrapper-android:0.0.5:onionwrapper-android-0.0.5.aar:d761854dac454616b3e0ca099b2cd17060365ce4316afe495cc7ae86b6c81d15',
+            'org.briarproject:onionwrapper-core:0.0.5:onionwrapper-core-0.0.5.jar:9071678323535cb3dfe0f3add96066037db43ea024333eba0117c759bcbd8d63',
+            'org.briarproject:snowflake-android:2.5.1:snowflake-android-2.5.1.jar:88ec81c17b1b6fa884d06839dec0330e328b45c89f88c970a213ce91ca8eac87',
+            'org.briarproject:tor-android:0.4.7.14:tor-android-0.4.7.14.jar:d39faa3a8abb116136c191c6ebadf8ea0e1f3e4785076d2c66a7b3b0f26988a2',
+            'org.checkerframework:checker-compat-qual:2.5.5:checker-compat-qual-2.5.5.jar:11d134b245e9cacc474514d2d66b5b8618f8039a1465cdc55bbc0b34e0008b7a',
+            'org.checkerframework:checker-qual:3.12.0:checker-qual-3.12.0.jar:ff10785ac2a357ec5de9c293cb982a2cbb605c0309ea4cc1cb9b9bc6dbe7f3cb',
+            'org.hamcrest:hamcrest-core:2.1:hamcrest-core-2.1.jar:e09109e54a289d88506b9bfec987ddd199f4217c9464132668351b9a4f00bee9',
+            'org.hamcrest:hamcrest-library:2.1:hamcrest-library-2.1.jar:b7e2b6895b3b679f0e47b6380fda391b225e9b78505db9d8bdde8d3cc8d52a21',
+            'org.hamcrest:hamcrest:2.1:hamcrest-2.1.jar:ba93b2e3a562322ba432f0a1b53addcc55cb188253319a020ed77f824e692050',
+            'org.jacoco:org.jacoco.agent:0.8.7:org.jacoco.agent-0.8.7.jar:9cbcc986e0fbe821a78ff1f8f7d5216f200e5eb124e7f6837d1dc4a77b28b143',
+            'org.jacoco:org.jacoco.ant:0.8.7:org.jacoco.ant-0.8.7.jar:97ca96a382c3f23a44d8eb4c4e6c3742a30cb8005774a76ced0fc4806ce49605',
+            'org.jacoco:org.jacoco.core:0.8.7:org.jacoco.core-0.8.7.jar:ad7739b5fb5969aa1a8aead3d74ed54dc82ed012f1f10f336bd1b96e71c1a13c',
+            'org.jacoco:org.jacoco.report:0.8.7:org.jacoco.report-0.8.7.jar:cc89258623700a6c932592153cb528785876b6da183d5431f97efbba6f020e5b',
+            'org.jetbrains.kotlin:kotlin-reflect:1.6.10:kotlin-reflect-1.6.10.jar:3277ac102ae17aad10a55abec75ff5696c8d109790396434b496e75087854203',
+            'org.jetbrains.kotlin:kotlin-stdlib-common:1.7.0:kotlin-stdlib-common-1.7.0.jar:59c6ff64fe9a6604afce03e8aaa75f83586c6030ac71fb0b34ee7cdefed3618f',
+            'org.jetbrains.kotlin:kotlin-stdlib-common:1.8.0:kotlin-stdlib-common-1.8.0.jar:78ef93b59e603cc0fe51def9bd4c037b07cbace3b3b7806d1a490a42bc1f4cb2',
+            'org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.7.0:kotlin-stdlib-jdk7-1.7.0.jar:07e91be9b2ca20672d2bdb7e181b766e73453a2da13492b5ddaee8fa47aea239',
+            'org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.8.0:kotlin-stdlib-jdk7-1.8.0.jar:4c889d1d9803f5f2eb6c1592a6b7e62369ac7660c9eee15aba16fec059163666',
+            'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.7.0:kotlin-stdlib-jdk8-1.7.0.jar:cf058e11db1dfc9944680c8c61b95ac689aaaa8a3eb30bced028100f038f030b',
+            'org.jetbrains.kotlin:kotlin-stdlib:1.7.0:kotlin-stdlib-1.7.0.jar:aa88e9625577957f3249a46cb6e166ee09b369e600f7a11d148d16b0a6d87f05',
+            'org.jetbrains.kotlin:kotlin-stdlib:1.8.0:kotlin-stdlib-1.8.0.jar:c77bef8774640b9fb9d6e217459ff220dae59878beb7d2e4b430506feffc654e',
+            'org.jetbrains.kotlinx:kotlinx-metadata-jvm:0.5.0:kotlinx-metadata-jvm-0.5.0.jar:ca063a96639b08b9eaa0de4d65e899480740a6efbe28ab9a8681a2ced03055a4',
+            'org.jetbrains:annotations:13.0:annotations-13.0.jar:ace2a10dc8e2d5fd34925ecac03e4988b2c0f851650c94b8cef49ba1bd111478',
+            'org.jmock:jmock-imposters:2.12.0:jmock-imposters-2.12.0.jar:3b836269745a137c9b2347e8d7c2104845b126ef04f012d6bfd94f1a7dea7b09',
+            'org.jmock:jmock-junit4:2.12.0:jmock-junit4-2.12.0.jar:3233062fc889637c151a24f1ee086bad04321ab7d8264fef279daff0fa27205b',
+            'org.jmock:jmock-legacy:2.12.0:jmock-legacy-2.12.0.jar:dea3a9cca653d082e2fe7e40232e982fe03a9984c7d67ceff24f3e03fe580dcd',
+            'org.jmock:jmock-testjar:2.12.0:jmock-testjar-2.12.0.jar:efefbcf6cd294d0e29f0c46eb2a3380d4ca4e1763ff719c69e2f2ac62f564a04',
+            'org.jmock:jmock:2.12.0:jmock-2.12.0.jar:266d07314c0cd343c46ff8a55601272de8cf406807caf55e6f313295f83d10be',
+            'org.objenesis:objenesis:3.0.1:objenesis-3.0.1.jar:7a8ff780b9ff48415d7c705f60030b0acaa616e7f823c98eede3b63508d4e984',
+            'org.ow2.asm:asm-analysis:9.1:asm-analysis-9.1.jar:81a88041b1b8beda5a8a99646098046c48709538270c49def68abff25ac3be34',
+            'org.ow2.asm:asm-commons:9.1:asm-commons-9.1.jar:afcb26dc1fc12c0c4a99ada670908dd82e18dfc488caf5ee92546996b470c00c',
+            'org.ow2.asm:asm-tree:9.1:asm-tree-9.1.jar:fd00afa49e9595d7646205b09cecb4a776a8ff0ba06f2d59b8f7bf9c704b4a73',
+            'org.ow2.asm:asm:7.1:asm-7.1.jar:4ab2fa2b6d2cc9ccb1eaa05ea329c407b47b13ed2915f62f8c4b8cc96258d4de',
+            'org.ow2.asm:asm:9.1:asm-9.1.jar:cda4de455fab48ff0bcb7c48b4639447d4de859a7afc30a094a986f0936beba2',
     ]
 }

bramble-api/src/main/java/org/briarproject/bramble/api/FeatureFlags.java

@@ -11,8 +11,6 @@ public interface FeatureFlags {
 
 	boolean shouldEnableDisappearingMessages();
 
-	boolean shouldEnableMailbox();
-
 	boolean shouldEnablePrivateGroupsInCore();
 
 	boolean shouldEnableForumsInCore();

bramble-api/src/main/java/org/briarproject/bramble/api/client/BdfMessageValidator.java

@@ -16,6 +16,7 @@ import java.util.logging.Logger;
 
 import javax.annotation.concurrent.Immutable;
 
+import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.api.transport.TransportConstants.MAX_CLOCK_DIFFERENCE;
 
 @Immutable
@@ -23,17 +24,30 @@ import static org.briarproject.bramble.api.transport.TransportConstants.MAX_CLOC
 public abstract class BdfMessageValidator implements MessageValidator {
 
 	protected static final Logger LOG =
-			Logger.getLogger(BdfMessageValidator.class.getName());
+			getLogger(BdfMessageValidator.class.getName());
 
 	protected final ClientHelper clientHelper;
 	protected final MetadataEncoder metadataEncoder;
 	protected final Clock clock;
+	protected final boolean canonical;
 
+	/**
+	 * Transitional alternative to
+	 * {@link #BdfMessageValidator(ClientHelper, MetadataEncoder, Clock)} that
+	 * accepts messages in non-canonical form, for backward compatibility.
+	 */
+	@Deprecated
 	protected BdfMessageValidator(ClientHelper clientHelper,
-			MetadataEncoder metadataEncoder, Clock clock) {
+			MetadataEncoder metadataEncoder, Clock clock, boolean canonical) {
 		this.clientHelper = clientHelper;
 		this.metadataEncoder = metadataEncoder;
 		this.clock = clock;
+		this.canonical = canonical;
+	}
+
+	protected BdfMessageValidator(ClientHelper clientHelper,
+			MetadataEncoder metadataEncoder, Clock clock) {
+		this(clientHelper, metadataEncoder, clock, true);
 	}
 
 	protected abstract BdfMessageContext validateMessage(Message m, Group g,
@@ -49,7 +63,7 @@ public abstract class BdfMessageValidator implements MessageValidator {
 					"Timestamp is too far in the future");
 		}
 		try {
-			BdfList bodyList = clientHelper.toList(m.getBody());
+			BdfList bodyList = clientHelper.toList(m, canonical);
 			BdfMessageContext result = validateMessage(m, g, bodyList);
 			Metadata meta = metadataEncoder.encode(result.getDictionary());
 			return new MessageContext(meta, result.getDependencies());

bramble-api/src/main/java/org/briarproject/bramble/api/client/ClientHelper.java

@@ -49,6 +49,18 @@ public interface ClientHelper {
 	BdfList getMessageAsList(Transaction txn, MessageId m) throws DbException,
 			FormatException;
 
+	/**
+	 * Transitional alternative to
+	 * {@link #getMessageAsList(Transaction, MessageId)} that allows the
+	 * message to be in non-canonical form, for backward compatibility.
+	 *
+	 * @param canonical True if the message must be in canonical form (a
+	 * {@link FormatException} will be thrown if it's not.
+	 */
+	@Deprecated
+	BdfList getMessageAsList(Transaction txn, MessageId m, boolean canonical)
+			throws DbException, FormatException;
+
 	BdfDictionary getGroupMetadataAsDictionary(GroupId g) throws DbException,
 			FormatException;
 
@@ -106,6 +118,16 @@ public interface ClientHelper {
 
 	BdfList toList(Message m) throws FormatException;
 
+	/**
+	 * Transitional alternative to {@link #toList(Message)} that allows the
+	 * message to be in non-canonical form, for backward compatibility.
+	 *
+	 * @param canonical True if the message must be in canonical form (a
+	 * {@link FormatException} will be thrown if it's not.
+	 */
+	@Deprecated
+	BdfList toList(Message m, boolean canonical) throws FormatException;
+
 	BdfList toList(Author a);
 
 	byte[] sign(String label, BdfList toSign, PrivateKey privateKey)

bramble-api/src/main/java/org/briarproject/bramble/api/crypto/CryptoComponent.java

@@ -54,6 +54,38 @@ public interface CryptoComponent {
 			KeyPair ourKeyPair, byte[]... inputs)
 			throws GeneralSecurityException;
 
+	/**
+	 * Derives a shared secret from two static and two ephemeral key pairs.
+	 * <p>
+	 * Do not use this method for new protocols. The shared secret can be
+	 * re-derived using the ephemeral public keys and both static private
+	 * keys, so keys derived from the shared secret should not be used if
+	 * forward secrecy is required. Use {@link #deriveSharedSecret(String,
+	 * PublicKey, PublicKey, KeyPair, KeyPair, boolean, byte[]...)} instead.
+	 * <p>
+	 * TODO: Remove this after a reasonable migration period (added 2023-03-10).
+	 * <p>
+	 *
+	 * @param label A namespaced label indicating the purpose of this shared
+	 * secret, to prevent it from being repurposed or colliding with a shared
+	 * secret derived for another purpose
+	 * @param theirStaticPublicKey The static public key of the remote party
+	 * @param theirEphemeralPublicKey The ephemeral public key of the remote
+	 * party
+	 * @param ourStaticKeyPair The static key pair of the local party
+	 * @param ourEphemeralKeyPair The ephemeral key pair of the local party
+	 * @param alice True if the local party is Alice
+	 * @param inputs Additional inputs that will be included in the
+	 * derivation of the shared secret
+	 * @return The shared secret
+	 */
+	@Deprecated
+	SecretKey deriveSharedSecretBadly(String label,
+			PublicKey theirStaticPublicKey, PublicKey theirEphemeralPublicKey,
+			KeyPair ourStaticKeyPair, KeyPair ourEphemeralKeyPair,
+			boolean alice, byte[]... inputs)
+			throws GeneralSecurityException;
+
 	/**
 	 * Derives a shared secret from two static and two ephemeral key pairs.
 	 *

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfDictionary.java

@@ -10,8 +10,29 @@ import java.util.TreeMap;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.NotThreadSafe;
 
+/**
+ * A BDF dictionary contains zero or more key-value pairs, where the keys
+ * are strings and the values are BDF objects, which may be primitive types
+ * (null, boolean, integer, float, string, raw) or nested containers (list,
+ * dictionary).
+ * <p>
+ * Note that a BDF integer has the same range as a Java long, while a BDF
+ * float has the same range as a Java double. Method names in this class
+ * correspond to the Java types.
+ * <p>
+ * The getX() methods throw {@link FormatException} if the specified key is
+ * absent, the value is null, or the value does not have the requested type.
+ * <p>
+ * The getOptionalX() methods return null if the specified key is absent or
+ * the value is null, or throw {@link FormatException} if the value does not
+ * have the requested type.
+ * <p>
+ * The getX() methods that take a default value return the default value if
+ * the specified key is absent or the value is null, or throw
+ * {@link FormatException} if the value does not have the requested type.
+ */
 @NotThreadSafe
-public class BdfDictionary extends TreeMap<String, Object> {
+public final class BdfDictionary extends TreeMap<String, Object> {
 
 	public static final Object NULL_VALUE = new Object();
 
@@ -39,9 +60,9 @@ public class BdfDictionary extends TreeMap<String, Object> {
 	}
 
 	public Boolean getBoolean(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof Boolean) return (Boolean) o;
-		throw new FormatException();
+		Boolean value = getOptionalBoolean(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -52,19 +73,16 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public Boolean getBoolean(String key, Boolean defaultValue) {
-		Object o = get(key);
-		if (o instanceof Boolean) return (Boolean) o;
-		return defaultValue;
+	public Boolean getBoolean(String key, Boolean defaultValue)
+			throws FormatException {
+		Boolean value = getOptionalBoolean(key);
+		return value == null ? defaultValue : value;
 	}
 
 	public Long getLong(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof Long) return (Long) o;
-		if (o instanceof Integer) return ((Integer) o).longValue();
-		if (o instanceof Short) return ((Short) o).longValue();
-		if (o instanceof Byte) return ((Byte) o).longValue();
-		throw new FormatException();
+		Long value = getOptionalLong(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -78,20 +96,69 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public Long getLong(String key, Long defaultValue) {
-		Object o = get(key);
-		if (o instanceof Long) return (Long) o;
-		if (o instanceof Integer) return ((Integer) o).longValue();
-		if (o instanceof Short) return ((Short) o).longValue();
-		if (o instanceof Byte) return ((Byte) o).longValue();
-		return defaultValue;
+	public Long getLong(String key, Long defaultValue) throws FormatException {
+		Long value = getOptionalLong(key);
+		return value == null ? defaultValue : value;
+	}
+
+	/**
+	 * Returns the integer with the specified key.
+	 * <p>
+	 * This method should be used in preference to
+	 * <code>getLong(key).intValue()</code> as it checks for
+	 * overflow/underflow.
+	 *
+	 * @throws FormatException if there is no value at the specified key,
+	 * or if the value is null or cannot be represented as a Java int.
+	 */
+	public Integer getInt(String key) throws FormatException {
+		Integer value = getOptionalInt(key);
+		if (value == null) throw new FormatException();
+		return value;
+	}
+
+	/**
+	 * Returns the integer with the specified key, or null if the key is
+	 * absent or the value is null.
+	 * <p>
+	 * This method should be used in preference to
+	 * <code>getOptionalLong(key).intValue()</code> as it checks for
+	 * overflow/underflow.
+	 *
+	 * @throws FormatException if the value at the specified key is not null
+	 * and cannot be represented as a Java int.
+	 */
+	@Nullable
+	public Integer getOptionalInt(String key) throws FormatException {
+		Long value = getOptionalLong(key);
+		if (value == null) return null;
+		if (value < Integer.MIN_VALUE || value > Integer.MAX_VALUE) {
+			throw new FormatException();
+		}
+		return value.intValue();
+	}
+
+	/**
+	 * Returns the integer with the specified key, or the given default
+	 * value if the key is absent or the value is null.
+	 * <p>
+	 * This method should be used in preference to
+	 * <code>getLong(key, defaultValue).intValue()</code> as it checks for
+	 * overflow/underflow.
+	 *
+	 * @throws FormatException if the value at the specified key is not null
+	 * and cannot be represented as a Java int.
+	 */
+	public Integer getInt(String key, Integer defaultValue)
+			throws FormatException {
+		Integer value = getOptionalInt(key);
+		return value == null ? defaultValue : value;
 	}
 
 	public Double getDouble(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof Double) return (Double) o;
-		if (o instanceof Float) return ((Float) o).doubleValue();
-		throw new FormatException();
+		Double value = getOptionalDouble(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -103,17 +170,16 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public Double getDouble(String key, Double defaultValue) {
-		Object o = get(key);
-		if (o instanceof Double) return (Double) o;
-		if (o instanceof Float) return ((Float) o).doubleValue();
-		return defaultValue;
+	public Double getDouble(String key, Double defaultValue)
+			throws FormatException {
+		Double value = getOptionalDouble(key);
+		return value == null ? defaultValue : value;
 	}
 
 	public String getString(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof String) return (String) o;
-		throw new FormatException();
+		String value = getOptionalString(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -124,17 +190,16 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public String getString(String key, String defaultValue) {
-		Object o = get(key);
-		if (o instanceof String) return (String) o;
-		return defaultValue;
+	public String getString(String key, String defaultValue)
+			throws FormatException {
+		String value = getOptionalString(key);
+		return value == null ? defaultValue : value;
 	}
 
 	public byte[] getRaw(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof byte[]) return (byte[]) o;
-		if (o instanceof Bytes) return ((Bytes) o).getBytes();
-		throw new FormatException();
+		byte[] value = getOptionalRaw(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -146,17 +211,16 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public byte[] getRaw(String key, byte[] defaultValue) {
-		Object o = get(key);
-		if (o instanceof byte[]) return (byte[]) o;
-		if (o instanceof Bytes) return ((Bytes) o).getBytes();
-		return defaultValue;
+	public byte[] getRaw(String key, byte[] defaultValue)
+			throws FormatException {
+		byte[] value = getOptionalRaw(key);
+		return value == null ? defaultValue : value;
 	}
 
 	public BdfList getList(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof BdfList) return (BdfList) o;
-		throw new FormatException();
+		BdfList value = getOptionalList(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -167,16 +231,16 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public BdfList getList(String key, BdfList defaultValue) {
-		Object o = get(key);
-		if (o instanceof BdfList) return (BdfList) o;
-		return defaultValue;
+	public BdfList getList(String key, BdfList defaultValue)
+			throws FormatException {
+		BdfList value = getOptionalList(key);
+		return value == null ? defaultValue : value;
 	}
 
 	public BdfDictionary getDictionary(String key) throws FormatException {
-		Object o = get(key);
-		if (o instanceof BdfDictionary) return (BdfDictionary) o;
-		throw new FormatException();
+		BdfDictionary value = getOptionalDictionary(key);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -188,9 +252,9 @@ public class BdfDictionary extends TreeMap<String, Object> {
 		throw new FormatException();
 	}
 
-	public BdfDictionary getDictionary(String key, BdfDictionary defaultValue) {
-		Object o = get(key);
-		if (o instanceof BdfDictionary) return (BdfDictionary) o;
-		return defaultValue;
+	public BdfDictionary getDictionary(String key, BdfDictionary defaultValue)
+			throws FormatException {
+		BdfDictionary value = getOptionalDictionary(key);
+		return value == null ? defaultValue : value;
 	}
 }

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfEntry.java

@@ -6,6 +6,11 @@ import java.util.Map.Entry;
 
 import javax.annotation.concurrent.Immutable;
 
+/**
+ * A convenience class for building {@link BdfDictionary BdfDictionaries}
+ * via the {@link BdfDictionary#of(Entry[]) factory method}. Entries in
+ * BdfDictionaries do not have to be BdfEntries.
+ */
 @Immutable
 @NotNullByDefault
 public class BdfEntry implements Entry<String, Object>, Comparable<BdfEntry> {

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfList.java

@@ -12,8 +12,31 @@ import javax.annotation.concurrent.NotThreadSafe;
 
 import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
 
+/**
+ * A BDF list contains zero or more BDF objects, which may be primitive types
+ * (null, boolean, integer, float, string, raw) or nested containers (list,
+ * dictionary).
+ * <p>
+ * Note that a BDF integer has the same range as a Java long, while a BDF
+ * float has the same range as a Java double. Method names in this class
+ * correspond to the Java types.
+ * <p>
+ * The getX() methods throw {@link FormatException} if the object at the
+ * specified index is null or does not have the requested type.
+ * <p>
+ * The getOptionalX() methods return null if the object at the specified
+ * index is null, or throw {@link FormatException} if the object does not
+ * have the requested type.
+ * <p>
+ * The getX() methods that take a default value return the default value if
+ * the object at the specified index is null, or throw
+ * {@link FormatException} if the object does not have the requested type.
+ * <p>
+ * All of the getters throw {@link FormatException} if the specified index is
+ * out of range.
+ */
 @NotThreadSafe
-public class BdfList extends ArrayList<Object> {
+public final class BdfList extends ArrayList<Object> {
 
 	/**
 	 * Factory method for constructing lists inline.
@@ -33,15 +56,15 @@ public class BdfList extends ArrayList<Object> {
 		super(items);
 	}
 
+	@SuppressWarnings("BooleanMethodIsAlwaysInverted")
 	private boolean isInRange(int index) {
 		return index >= 0 && index < size();
 	}
 
 	public Boolean getBoolean(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof Boolean) return (Boolean) o;
-		throw new FormatException();
+		Boolean value = getOptionalBoolean(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -53,21 +76,16 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public Boolean getBoolean(int index, Boolean defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof Boolean) return (Boolean) o;
-		return defaultValue;
+	public Boolean getBoolean(int index, Boolean defaultValue)
+			throws FormatException {
+		Boolean value = getOptionalBoolean(index);
+		return value == null ? defaultValue : value;
 	}
 
 	public Long getLong(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof Long) return (Long) o;
-		if (o instanceof Integer) return ((Integer) o).longValue();
-		if (o instanceof Short) return ((Short) o).longValue();
-		if (o instanceof Byte) return ((Byte) o).longValue();
-		throw new FormatException();
+		Long value = getOptionalLong(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -82,22 +100,70 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public Long getLong(int index, Long defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof Long) return (Long) o;
-		if (o instanceof Integer) return ((Integer) o).longValue();
-		if (o instanceof Short) return ((Short) o).longValue();
-		if (o instanceof Byte) return ((Byte) o).longValue();
-		return defaultValue;
+	public Long getLong(int index, Long defaultValue) throws FormatException {
+		Long value = getOptionalLong(index);
+		return value == null ? defaultValue : value;
+	}
+
+	/**
+	 * Returns the integer at the specified index.
+	 * <p>
+	 * This method should be used in preference to
+	 * <code>getLong(index).intValue()</code> as it checks for
+	 * overflow/underflow.
+	 *
+	 * @throws FormatException if the index is out of range, or if the
+	 * value at the specified index is null or cannot be represented as a
+	 * Java int.
+	 */
+	public Integer getInt(int index) throws FormatException {
+		Integer value = getOptionalInt(index);
+		if (value == null) throw new FormatException();
+		return value;
+	}
+
+	/**
+	 * Returns the integer at the specified index, or null if the object at
+	 * the specified index is null.
+	 * <p>
+	 * This method should be used in preference to
+	 * <code>getOptionalLong(index).intValue()</code> as it checks for
+	 * overflow/underflow.
+	 *
+	 * @throws FormatException if the index is out of range, or if the value
+	 * at the specified index cannot be represented as a Java int.
+	 */
+	@Nullable
+	public Integer getOptionalInt(int index) throws FormatException {
+		Long value = getOptionalLong(index);
+		if (value == null) return null;
+		if (value < Integer.MIN_VALUE || value > Integer.MAX_VALUE) {
+			throw new FormatException();
+		}
+		return value.intValue();
+	}
+
+	/**
+	 * Returns the integer at the specified index, or the given default value
+	 * if the object at the specified index is null.
+	 * <p>
+	 * This method should be used in preference to
+	 * <code>getLong(index, defaultValue).intValue()</code> as it checks for
+	 * overflow/underflow.
+	 *
+	 * @throws FormatException if the index is out of range, or if the value
+	 * at the specified index cannot be represented as a Java int.
+	 */
+	public Integer getInt(int index, Integer defaultValue)
+			throws FormatException {
+		Integer value = getOptionalInt(index);
+		return value == null ? defaultValue : value;
 	}
 
 	public Double getDouble(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof Double) return (Double) o;
-		if (o instanceof Float) return ((Float) o).doubleValue();
-		throw new FormatException();
+		Double value = getOptionalDouble(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -110,19 +176,16 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public Double getDouble(int index, Double defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof Double) return (Double) o;
-		if (o instanceof Float) return ((Float) o).doubleValue();
-		return defaultValue;
+	public Double getDouble(int index, Double defaultValue)
+			throws FormatException {
+		Double value = getOptionalDouble(index);
+		return value == null ? defaultValue : value;
 	}
 
 	public String getString(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof String) return (String) o;
-		throw new FormatException();
+		String value = getOptionalString(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -134,19 +197,16 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public String getString(int index, String defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof String) return (String) o;
-		return defaultValue;
+	public String getString(int index, String defaultValue)
+			throws FormatException {
+		String value = getOptionalString(index);
+		return value == null ? defaultValue : value;
 	}
 
 	public byte[] getRaw(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof byte[]) return (byte[]) o;
-		if (o instanceof Bytes) return ((Bytes) o).getBytes();
-		throw new FormatException();
+		byte[] value = getOptionalRaw(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -159,19 +219,16 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public byte[] getRaw(int index, byte[] defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof byte[]) return (byte[]) o;
-		if (o instanceof Bytes) return ((Bytes) o).getBytes();
-		return defaultValue;
+	public byte[] getRaw(int index, byte[] defaultValue)
+			throws FormatException {
+		byte[] value = getOptionalRaw(index);
+		return value == null ? defaultValue : value;
 	}
 
 	public BdfList getList(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof BdfList) return (BdfList) o;
-		throw new FormatException();
+		BdfList value = getOptionalList(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -183,18 +240,16 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public BdfList getList(int index, BdfList defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof BdfList) return (BdfList) o;
-		return defaultValue;
+	public BdfList getList(int index, BdfList defaultValue)
+			throws FormatException {
+		BdfList value = getOptionalList(index);
+		return value == null ? defaultValue : value;
 	}
 
 	public BdfDictionary getDictionary(int index) throws FormatException {
-		if (!isInRange(index)) throw new FormatException();
-		Object o = get(index);
-		if (o instanceof BdfDictionary) return (BdfDictionary) o;
-		throw new FormatException();
+		BdfDictionary value = getOptionalDictionary(index);
+		if (value == null) throw new FormatException();
+		return value;
 	}
 
 	@Nullable
@@ -207,10 +262,9 @@ public class BdfList extends ArrayList<Object> {
 		throw new FormatException();
 	}
 
-	public BdfDictionary getDictionary(int index, BdfDictionary defaultValue) {
-		if (!isInRange(index)) return defaultValue;
-		Object o = get(index);
-		if (o instanceof BdfDictionary) return (BdfDictionary) o;
-		return defaultValue;
+	public BdfDictionary getDictionary(int index, BdfDictionary defaultValue)
+			throws FormatException {
+		BdfDictionary value = getOptionalDictionary(index);
+		return value == null ? defaultValue : value;
 	}
 }

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReader.java

@@ -1,76 +1,178 @@
 package org.briarproject.bramble.api.data;
 
+import org.briarproject.bramble.api.FormatException;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.IOException;
 
+/**
+ * An interface for reading BDF objects from an input stream.
+ * <p>
+ * The readX() methods throw {@link FormatException} if the data is not in
+ * canonical form, but the hasX() and skipX() methods do not check for
+ * canonical form.
+ */
 @NotNullByDefault
 public interface BdfReader {
 
 	int DEFAULT_NESTED_LIMIT = 5;
 	int DEFAULT_MAX_BUFFER_SIZE = 64 * 1024;
 
+	/**
+	 * Returns true if the reader has reached the end of its input stream.
+	 */
 	boolean eof() throws IOException;
 
+	/**
+	 * Closes the reader's input stream.
+	 */
 	void close() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF null.
+	 */
 	boolean hasNull() throws IOException;
 
+	/**
+	 * Reads a BDF null from the input.
+	 */
 	void readNull() throws IOException;
 
+	/**
+	 * Skips over a BDF null.
+	 */
 	void skipNull() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF boolean.
+	 */
 	boolean hasBoolean() throws IOException;
 
+	/**
+	 * Reads a BDF boolean from the input and returns it.
+	 */
 	boolean readBoolean() throws IOException;
 
+	/**
+	 * Skips over a BDF boolean.
+	 */
 	void skipBoolean() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF integer, which
+	 * has the same range as a Java long.
+	 */
 	boolean hasLong() throws IOException;
 
+	/**
+	 * Reads a BDF integer from the input and returns it as a Java long.
+	 */
 	long readLong() throws IOException;
 
+	/**
+	 * Skips over a BDF integer.
+	 */
 	void skipLong() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF integer and the
+	 * value would fit within the range of a Java int.
+	 */
+	boolean hasInt() throws IOException;
+
+	/**
+	 * Reads a BDF integer from the input and returns it as a Java int.
+	 *
+	 * @throws FormatException if the value exceeds the range of a Java int.
+	 */
+	int readInt() throws IOException;
+
+	/**
+	 * Skips over a BDF integer.
+	 *
+	 * @throws FormatException if the value exceeds the range of a Java int.
+	 */
+	void skipInt() throws IOException;
+
+	/**
+	 * Returns true if the next object in the input is a BDF float, which has
+	 * the same range as a Java double.
+	 */
 	boolean hasDouble() throws IOException;
 
+	/**
+	 * Reads a BDF float from the input and returns it as a Java double.
+	 */
 	double readDouble() throws IOException;
 
+	/**
+	 * Skips over a BDF float.
+	 */
 	void skipDouble() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF string.
+	 */
 	boolean hasString() throws IOException;
 
+	/**
+	 * Reads a BDF string from the input.
+	 *
+	 * @throws IOException If the string is not valid UTF-8.
+	 */
 	String readString() throws IOException;
 
+	/**
+	 * Skips over a BDF string without checking whether it is valid UTF-8.
+	 */
 	void skipString() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF raw.
+	 */
 	boolean hasRaw() throws IOException;
 
+	/**
+	 * Reads a BDF raw from the input and returns it as a byte array.
+	 */
 	byte[] readRaw() throws IOException;
 
+	/**
+	 * Skips over a BDF raw.
+	 */
 	void skipRaw() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF list.
+	 */
 	boolean hasList() throws IOException;
 
+	/**
+	 * Reads a BDF list from the input and returns it. The list's contents
+	 * are parsed and validated.
+	 */
 	BdfList readList() throws IOException;
 
-	void readListStart() throws IOException;
-
-	boolean hasListEnd() throws IOException;
-
-	void readListEnd() throws IOException;
-
+	/**
+	 * Skips over a BDF list. The list's contents are parsed (to determine
+	 * their length) but not validated.
+	 */
 	void skipList() throws IOException;
 
+	/**
+	 * Returns true if the next object in the input is a BDF dictionary.
+	 */
 	boolean hasDictionary() throws IOException;
 
+	/**
+	 * Reads a BDF dictionary from the input and returns it. The dictionary's
+	 * contents are parsed and validated.
+	 */
 	BdfDictionary readDictionary() throws IOException;
 
-	void readDictionaryStart() throws IOException;
-
-	boolean hasDictionaryEnd() throws IOException;
-
-	void readDictionaryEnd() throws IOException;
-
+	/**
+	 * Skips over a BDF dictionary. The dictionary's contents are parsed
+	 * (to determine their length) but not validated.
+	 */
 	void skipDictionary() throws IOException;
 }

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReaderFactory.java

@@ -9,6 +9,14 @@ public interface BdfReaderFactory {
 
 	BdfReader createReader(InputStream in);
 
+	/**
+	 * Transitional alternative to {@link #createReader(InputStream)} that
+	 * can create a reader that accepts non-canonical input, for backward
+	 * compatibility.
+	 */
+	@Deprecated
+	BdfReader createReader(InputStream in, boolean canonical);
+
 	BdfReader createReader(InputStream in, int nestedLimit,
-			int maxBufferSize);
+			int maxBufferSize, boolean canonical);
 }

bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfWriter.java

@@ -1,36 +1,74 @@
 package org.briarproject.bramble.api.data;
 
+import org.briarproject.bramble.api.FormatException;
+
 import java.io.IOException;
 import java.util.Collection;
 import java.util.Map;
 
+/**
+ * An interface for writing BDF objects to an output stream. The BDF output
+ * is in canonical form, ie integers and length fields are represented using
+ * the minimum number of bytes and dictionary keys are unique and sorted in
+ * lexicographic order.
+ */
 public interface BdfWriter {
 
+	/**
+	 * Flushes the writer's output stream.
+	 */
 	void flush() throws IOException;
 
+	/**
+	 * Closes the writer's output stream.
+	 */
 	void close() throws IOException;
 
+	/**
+	 * Writes a BDF null to the output stream.
+	 */
 	void writeNull() throws IOException;
 
+	/**
+	 * Writes a BDF boolean to the output stream.
+	 */
 	void writeBoolean(boolean b) throws IOException;
 
+	/**
+	 * Writes a BDF integer (which has the same range as a Java long) to the
+	 * output stream.
+	 */
 	void writeLong(long l) throws IOException;
 
+	/**
+	 * Writes a BDF float (which has the same range as a Java double) to the
+	 * output stream.
+	 */
 	void writeDouble(double d) throws IOException;
 
+	/**
+	 * Writes a BDF string (which uses UTF-8 encoding) to the output stream.
+	 */
 	void writeString(String s) throws IOException;
 
+	/**
+	 * Writes a BDF raw to the output stream.
+	 */
 	void writeRaw(byte[] b) throws IOException;
 
+	/**
+	 * Writes a BDF list to the output stream.
+	 *
+	 * @throws FormatException if the contents of the given collection cannot
+	 * be represented as (nested) BDF objects.
+	 */
 	void writeList(Collection<?> c) throws IOException;
 
-	void writeListStart() throws IOException;
-
-	void writeListEnd() throws IOException;
-
+	/**
+	 * Writes a BDF dictionary to the output stream.
+	 *
+	 * @throws FormatException if the contents of the given map cannot be
+	 * represented as (nested) BDF objects.
+	 */
 	void writeDictionary(Map<?, ?> m) throws IOException;
-
-	void writeDictionaryStart() throws IOException;
-
-	void writeDictionaryEnd() throws IOException;
 }

bramble-api/src/main/java/org/briarproject/bramble/api/keyagreement/KeyAgreementConstants.java

@@ -1,18 +1,26 @@
 package org.briarproject.bramble.api.keyagreement;
 
-public interface KeyAgreementConstants {
+import org.briarproject.bramble.api.mailbox.MailboxConstants;
 
-	/**
-	 * The version of the BQP protocol used in beta releases. This version
-	 * number is reserved.
-	 */
-	byte BETA_PROTOCOL_VERSION = 89;
+public interface KeyAgreementConstants {
 
 	/**
 	 * The current version of the BQP protocol.
 	 */
 	byte PROTOCOL_VERSION = 4;
 
+	/**
+	 * The QR code format identifier, used to distinguish BQP QR codes from
+	 * QR codes used for other purposes. See
+	 * {@link MailboxConstants#QR_FORMAT_ID}.
+	 */
+	byte QR_FORMAT_ID = 0;
+
+	/**
+	 * The QR code format version.
+	 */
+	byte QR_FORMAT_VERSION = PROTOCOL_VERSION;
+
 	/**
 	 * The length of the BQP key commitment in bytes.
 	 */

bramble-api/src/main/java/org/briarproject/bramble/api/keyagreement/PayloadParser.java

@@ -7,5 +7,5 @@ import java.io.IOException;
 @NotNullByDefault
 public interface PayloadParser {
 
-	Payload parse(byte[] raw) throws IOException;
+	Payload parse(String payload) throws IOException;
 }

bramble-api/src/main/java/org/briarproject/bramble/api/mailbox/MailboxConstants.java

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.api.mailbox;
 
+import org.briarproject.bramble.api.keyagreement.KeyAgreementConstants;
 import org.briarproject.bramble.api.plugin.TransportId;
 
 import java.util.List;
@@ -19,6 +20,18 @@ public interface MailboxConstants {
 	 */
 	TransportId ID = new TransportId("org.briarproject.bramble.mailbox");
 
+	/**
+	 * The QR code format identifier, used to distinguish mailbox QR codes
+	 * from QR codes used for other purposes. See
+	 * {@link KeyAgreementConstants#QR_FORMAT_ID};
+	 */
+	byte QR_FORMAT_ID = 1;
+
+	/**
+	 * The QR code format version.
+	 */
+	byte QR_FORMAT_VERSION = 0;
+
 	/**
 	 * Mailbox API versions that we support as a client. This is reported to our
 	 * contacts by {@link MailboxUpdateManager}.

bramble-api/src/main/java/org/briarproject/bramble/api/mailbox/MailboxManager.java

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.api.mailbox;
 
+import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
@@ -34,6 +35,16 @@ public interface MailboxManager {
 	 */
 	MailboxPairingTask startPairingTask(String qrCodePayload);
 
+	/**
+	 * Takes a textual QR code representation in
+	 * {@link org.briarproject.bramble.util.Base32} format and converts it
+	 * into a qrCodePayload as expected by {@link #startPairingTask(String)}.
+	 *
+	 * @throws FormatException when the provided payload did not include a
+	 * proper briar-mailbox:// link.
+	 */
+	String convertBase32Payload(String base32Payload) throws FormatException;
+
 	/**
 	 * Can be used by the UI to test the mailbox connection.
 	 *

bramble-api/src/main/java/org/briarproject/bramble/api/mailbox/MailboxPairingState.java

@@ -1,17 +1,44 @@
 package org.briarproject.bramble.api.mailbox;
 
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType;
+
 public abstract class MailboxPairingState {
 
-	public static class QrCodeReceived extends MailboxPairingState {
+	public abstract static class Pending extends MailboxPairingState {
+
+		public final long timeStarted;
+
+		private Pending(long timeStarted) {
+			this.timeStarted = timeStarted;
+		}
 	}
 
-	public static class Pairing extends MailboxPairingState {
+	public static class QrCodeReceived extends Pending {
+
+		public QrCodeReceived(long timeStarted) {
+			super(timeStarted);
+		}
+	}
+
+	public static class Pairing extends Pending {
+
+		public Pairing(long timeStarted) {
+			super(timeStarted);
+		}
 	}
 
 	public static class Paired extends MailboxPairingState {
 	}
 
 	public static class InvalidQrCode extends MailboxPairingState {
+
+		public final QrCodeType qrCodeType;
+		public final int formatVersion;
+
+		public InvalidQrCode(QrCodeType qrCodeType, int formatVersion) {
+			this.qrCodeType = qrCodeType;
+			this.formatVersion = formatVersion;
+		}
 	}
 
 	public static class MailboxAlreadyPaired extends MailboxPairingState {

bramble-api/src/main/java/org/briarproject/bramble/api/network/NetworkStatus.java

@@ -2,6 +2,7 @@ package org.briarproject.bramble.api.network;
 
 import org.briarproject.nullsafety.NotNullByDefault;
 
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
 @Immutable
@@ -27,4 +28,20 @@ public class NetworkStatus {
 	public boolean isIpv6Only() {
 		return ipv6Only;
 	}
+
+	@Override
+	public int hashCode() {
+		return (connected ? 1 : 0) | (wifi ? 2 : 0) | (ipv6Only ? 4 : 0);
+	}
+
+	@Override
+	public boolean equals(@Nullable Object o) {
+		if (o instanceof NetworkStatus) {
+			NetworkStatus s = (NetworkStatus) o;
+			return connected == s.connected
+					&& wifi == s.wifi
+					&& ipv6Only == s.ipv6Only;
+		}
+		return false;
+	}
 }

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

@@ -27,8 +27,6 @@ public interface TorConstants {
 	int PREF_TOR_NETWORK_AUTOMATIC = 0;
 	int PREF_TOR_NETWORK_WITHOUT_BRIDGES = 1;
 	int PREF_TOR_NETWORK_WITH_BRIDGES = 2;
-	// TODO: Remove when settings migration code is removed
-	int PREF_TOR_NETWORK_NEVER = 3;
 
 	// Default values for local settings
 	boolean DEFAULT_PREF_PLUGIN_ENABLE = true;

bramble-api/src/main/java/org/briarproject/bramble/api/qrcode/QrCodeClassifier.java

@@ -0,0 +1,16 @@
+package org.briarproject.bramble.api.qrcode;
+
+import org.briarproject.bramble.api.Pair;
+import org.briarproject.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface QrCodeClassifier {
+
+	enum QrCodeType {
+		BQP,
+		MAILBOX,
+		UNKNOWN
+	}
+
+	Pair<QrCodeType, Integer> classifyQrCode(String payload);
+}

bramble-api/src/main/java/org/briarproject/bramble/api/qrcode/WrongQrCodeTypeException.java

@@ -0,0 +1,25 @@
+package org.briarproject.bramble.api.qrcode;
+
+import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType;
+import org.briarproject.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+
+/**
+ * Thrown when a QR code that has been scanned does not have the expected type.
+ */
+@Immutable
+@NotNullByDefault
+public class WrongQrCodeTypeException extends FormatException {
+
+	private final QrCodeType qrCodeType;
+
+	public WrongQrCodeTypeException(QrCodeType qrCodeType) {
+		this.qrCodeType = qrCodeType;
+	}
+
+	public QrCodeType getQrCodeType() {
+		return qrCodeType;
+	}
+}

bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordReader.java

@@ -32,8 +32,15 @@ public interface RecordReader {
 	 * 'accept' or 'ignore' predicates
 	 */
 	@Nullable
-	Record readRecord(Predicate<Record> accept, Predicate<Record> ignore)
+	Record readRecord(RecordPredicate accept, RecordPredicate ignore)
 			throws IOException;
 
 	void close() throws IOException;
+
+	/**
+	 * Interface that reifies the generic interface {@code Predicate<Record>}
+	 * for easier testing.
+	 */
+	interface RecordPredicate extends Predicate<Record> {
+	}
 }

bramble-api/src/main/java/org/briarproject/bramble/api/system/LocationUtils.java

@@ -1,16 +0,0 @@
-package org.briarproject.bramble.api.system;
-
-import org.briarproject.nullsafety.NotNullByDefault;
-
-@NotNullByDefault
-public interface LocationUtils {
-
-	/**
-	 * Get the country the device is currently located in, or "" if it cannot
-	 * be determined.
-	 * <p>
-	 * The country codes are formatted upper-case and as per <a href="
-	 * https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2">ISO 3166-1 alpha 2</a>.
-	 */
-	String getCurrentCountry();
-}

bramble-api/src/main/java/org/briarproject/bramble/util/OsUtils.java

@@ -4,6 +4,8 @@ import org.briarproject.nullsafety.NotNullByDefault;
 
 import javax.annotation.Nullable;
 
+import static org.briarproject.bramble.util.StringUtils.startsWithIgnoreCase;
+
 @NotNullByDefault
 public class OsUtils {
 
@@ -13,15 +15,15 @@ public class OsUtils {
 	private static final String vendor = System.getProperty("java.vendor");
 
 	public static boolean isWindows() {
-		return os != null && os.contains("Windows");
+		return os != null && startsWithIgnoreCase(os, "Win");
 	}
 
 	public static boolean isMac() {
-		return os != null && os.contains("Mac OS");
+		return os != null && os.equalsIgnoreCase("Mac OS X");
 	}
 
 	public static boolean isLinux() {
-		return os != null && os.contains("Linux") && !isAndroid();
+		return os != null && startsWithIgnoreCase(os, "Linux") && !isAndroid();
 	}
 
 	public static boolean isAndroid() {

bramble-api/src/main/java/org/briarproject/bramble/util/PrivacyUtils.java

@@ -6,6 +6,7 @@ import java.net.Inet4Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
+import java.util.Locale;
 
 import javax.annotation.Nullable;
 
@@ -51,7 +52,7 @@ public class PrivacyUtils {
 	}
 
 	private static String scrubIpv6Address(byte[] ipv6) {
-		String hex = toHexString(ipv6).toLowerCase();
+		String hex = toHexString(ipv6).toLowerCase(Locale.US);
 		return hex.substring(0, 2) + "[scrubbed]" + hex.substring(30);
 	}
 

bramble-api/src/main/java/org/briarproject/bramble/util/StringUtils.java

@@ -3,7 +3,6 @@ package org.briarproject.bramble.util;
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.nullsafety.NotNullByDefault;
 
-import java.io.UnsupportedEncodingException;
 import java.nio.ByteBuffer;
 import java.nio.charset.CharacterCodingException;
 import java.nio.charset.Charset;
@@ -15,15 +14,21 @@ import java.util.regex.Pattern;
 import javax.annotation.Nullable;
 
 import static java.nio.charset.CodingErrorAction.IGNORE;
+import static java.nio.charset.CodingErrorAction.REPORT;
 import static java.util.regex.Pattern.CASE_INSENSITIVE;
 
+@SuppressWarnings("CharsetObjectCanBeUsed")
 @NotNullByDefault
 public class StringUtils {
 
-	private static final Charset UTF_8 = Charset.forName("UTF-8");
-	private static Pattern MAC = Pattern.compile("[0-9a-f]{2}:[0-9a-f]{2}:" +
-					"[0-9a-f]{2}:[0-9a-f]{2}:[0-9a-f]{2}:[0-9a-f]{2}",
-			CASE_INSENSITIVE);
+	public static final Charset UTF_8 = Charset.forName("UTF-8");
+	public static final Charset US_ASCII = Charset.forName("US-ASCII");
+	public static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1");
+
+	private static final Pattern MAC =
+			Pattern.compile("[0-9a-f]{2}:[0-9a-f]{2}:" +
+							"[0-9a-f]{2}:[0-9a-f]{2}:[0-9a-f]{2}:[0-9a-f]{2}",
+					CASE_INSENSITIVE);
 
 	private static final char[] HEX = new char[] {
 			'0', '1', '2', '3', '4', '5', '6', '7',
@@ -45,33 +50,41 @@ public class StringUtils {
 	}
 
 	public static byte[] toUtf8(String s) {
-		try {
-			return s.getBytes("UTF-8");
-		} catch (UnsupportedEncodingException e) {
-			throw new AssertionError(e);
-		}
+		return s.getBytes(UTF_8);
 	}
 
-	public static String fromUtf8(byte[] bytes) {
-		return fromUtf8(bytes, 0, bytes.length);
+	public static String fromUtf8(byte[] bytes) throws FormatException {
+		return fromUtf8(bytes, 0, bytes.length, true);
 	}
 
-	public static String fromUtf8(byte[] bytes, int off, int len) {
+	public static String fromUtf8(byte[] bytes, int off, int len)
+			throws FormatException {
+		return fromUtf8(bytes, off, len, true);
+	}
+
+	private static String fromUtf8(byte[] bytes, int off, int len,
+			boolean strict) throws FormatException {
 		CharsetDecoder decoder = UTF_8.newDecoder();
-		decoder.onMalformedInput(IGNORE);
-		decoder.onUnmappableCharacter(IGNORE);
+		decoder.onMalformedInput(strict ? REPORT : IGNORE);
+		decoder.onUnmappableCharacter(strict ? REPORT : IGNORE);
 		ByteBuffer buffer = ByteBuffer.wrap(bytes, off, len);
 		try {
 			return decoder.decode(buffer).toString();
 		} catch (CharacterCodingException e) {
-			throw new AssertionError(e);
+			throw new FormatException();
 		}
 	}
 
 	public static String truncateUtf8(String s, int maxUtf8Length) {
 		byte[] utf8 = toUtf8(s);
 		if (utf8.length <= maxUtf8Length) return s;
-		return fromUtf8(utf8, 0, maxUtf8Length);
+		// Don't be strict when converting back, so that if we truncate a
+		// multi-byte character the whole character gets dropped
+		try {
+			return fromUtf8(utf8, 0, maxUtf8Length, false);
+		} catch (FormatException e) {
+			throw new AssertionError(e);
+		}
 	}
 
 	/**
@@ -163,4 +176,9 @@ public class StringUtils {
 		}
 		return new String(c);
 	}
+
+	// see https://stackoverflow.com/a/38947571
+	static boolean startsWithIgnoreCase(String s, String prefix) {
+		return s.regionMatches(true, 0, prefix, 0, prefix.length());
+	}
 }

bramble-api/src/test/java/org/briarproject/bramble/api/data/BdfDictionaryTest.java

@@ -1,6 +1,7 @@
 package org.briarproject.bramble.api.data;
 
 import org.briarproject.bramble.api.Bytes;
+import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.test.BrambleTestCase;
 import org.junit.Test;
 
@@ -8,9 +9,12 @@ import java.util.Collections;
 import java.util.Iterator;
 import java.util.Map.Entry;
 
+import static java.lang.Boolean.TRUE;
+import static java.util.Collections.singletonMap;
 import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 public class BdfDictionaryTest extends BrambleTestCase {
@@ -19,20 +23,20 @@ public class BdfDictionaryTest extends BrambleTestCase {
 	public void testConstructors() {
 		assertEquals(Collections.<String, Object>emptyMap(),
 				new BdfDictionary());
-		assertEquals(Collections.singletonMap("foo", NULL_VALUE),
-				new BdfDictionary(Collections.singletonMap("foo", NULL_VALUE)));
+		assertEquals(singletonMap("foo", NULL_VALUE),
+				new BdfDictionary(singletonMap("foo", NULL_VALUE)));
 	}
 
 	@Test
 	public void testFactoryMethod() {
 		assertEquals(Collections.<String, Object>emptyMap(),
 				BdfDictionary.of());
-		assertEquals(Collections.singletonMap("foo", NULL_VALUE),
+		assertEquals(singletonMap("foo", NULL_VALUE),
 				BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)));
 	}
 
 	@Test
-	public void testIntegerPromotion() throws Exception {
+	public void testLongPromotion() throws Exception {
 		BdfDictionary d = new BdfDictionary();
 		d.put("foo", (byte) 1);
 		d.put("bar", (short) 2);
@@ -44,6 +48,33 @@ public class BdfDictionaryTest extends BrambleTestCase {
 		assertEquals(Long.valueOf(4), d.getLong("bam"));
 	}
 
+	@Test
+	public void testIntPromotionAndDemotion() throws Exception {
+		BdfDictionary d = new BdfDictionary();
+		d.put("foo", (byte) 1);
+		d.put("bar", (short) 2);
+		d.put("baz", 3);
+		d.put("bam", 4L);
+		assertEquals(Integer.valueOf(1), d.getInt("foo"));
+		assertEquals(Integer.valueOf(2), d.getInt("bar"));
+		assertEquals(Integer.valueOf(3), d.getInt("baz"));
+		assertEquals(Integer.valueOf(4), d.getInt("bam"));
+	}
+
+	@Test(expected = FormatException.class)
+	public void testIntUnderflow() throws Exception {
+		BdfDictionary d =
+				BdfDictionary.of(new BdfEntry("foo", Integer.MIN_VALUE - 1L));
+		d.getInt("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testIntOverflow() throws Exception {
+		BdfDictionary d =
+				BdfDictionary.of(new BdfEntry("foo", Integer.MAX_VALUE + 1L));
+		d.getInt("foo");
+	}
+
 	@Test
 	public void testFloatPromotion() throws Exception {
 		BdfDictionary d = new BdfDictionary();
@@ -67,7 +98,7 @@ public class BdfDictionaryTest extends BrambleTestCase {
 	}
 
 	@Test
-	public void testKeySetIteratorIsOrderedByKeys() throws Exception {
+	public void testKeySetIteratorIsOrderedByKeys() {
 		BdfDictionary d = new BdfDictionary();
 		d.put("a", 1);
 		d.put("d", 4);
@@ -86,7 +117,7 @@ public class BdfDictionaryTest extends BrambleTestCase {
 	}
 
 	@Test
-	public void testValuesIteratorIsOrderedByKeys() throws Exception {
+	public void testValuesIteratorIsOrderedByKeys() {
 		BdfDictionary d = new BdfDictionary();
 		d.put("a", 1);
 		d.put("d", 4);
@@ -105,7 +136,7 @@ public class BdfDictionaryTest extends BrambleTestCase {
 	}
 
 	@Test
-	public void testEntrySetIteratorIsOrderedByKeys() throws Exception {
+	public void testEntrySetIteratorIsOrderedByKeys() {
 		BdfDictionary d = new BdfDictionary();
 		d.put("a", 1);
 		d.put("d", 4);
@@ -130,4 +161,284 @@ public class BdfDictionaryTest extends BrambleTestCase {
 		assertEquals("d", e.getKey());
 		assertEquals(4, e.getValue());
 	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForBooleanThrowsFormatException()
+			throws Exception {
+		new BdfDictionary().getBoolean("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForLongThrowsFormatException()
+			throws Exception {
+		new BdfDictionary().getLong("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForIntThrowsFormatException() throws Exception {
+		new BdfDictionary().getInt("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForDoubleThrowsFormatException()
+			throws Exception {
+		new BdfDictionary().getDouble("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForStringThrowsFormatException()
+			throws Exception {
+		new BdfDictionary().getString("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForRawThrowsFormatException() throws Exception {
+		new BdfDictionary().getRaw("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForListThrowsFormatException()
+			throws Exception {
+		new BdfDictionary().getList("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testMissingValueForDictionaryThrowsFormatException()
+			throws Exception {
+		new BdfDictionary().getDictionary("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForBooleanThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getBoolean("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForLongThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getLong("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForIntThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getInt("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForDoubleThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getDouble("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForStringThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getString("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForRawThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getRaw("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForListThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getList("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForDictionaryThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", NULL_VALUE)).getDictionary("foo");
+	}
+
+	@Test
+	public void testOptionalMethodsReturnNullForMissingValue()
+			throws Exception {
+		testOptionalMethodsReturnNull(new BdfDictionary());
+	}
+
+	@Test
+	public void testOptionalMethodsReturnNullForNullValue() throws Exception {
+		BdfDictionary d = BdfDictionary.of(new BdfEntry("foo", NULL_VALUE));
+		testOptionalMethodsReturnNull(d);
+	}
+
+	private void testOptionalMethodsReturnNull(BdfDictionary d)
+			throws Exception {
+		assertNull(d.getOptionalBoolean("foo"));
+		assertNull(d.getOptionalLong("foo"));
+		assertNull(d.getOptionalInt("foo"));
+		assertNull(d.getOptionalDouble("foo"));
+		assertNull(d.getOptionalString("foo"));
+		assertNull(d.getOptionalRaw("foo"));
+		assertNull(d.getOptionalList("foo"));
+		assertNull(d.getOptionalDictionary("foo"));
+	}
+
+	@Test
+	public void testDefaultMethodsReturnDefaultForMissingValue()
+			throws Exception {
+		testDefaultMethodsReturnDefault(new BdfDictionary());
+	}
+
+	@Test
+	public void testDefaultMethodsReturnDefaultForNullValue() throws Exception {
+		BdfDictionary d = BdfDictionary.of(new BdfEntry("foo", NULL_VALUE));
+		testDefaultMethodsReturnDefault(d);
+	}
+
+	private void testDefaultMethodsReturnDefault(BdfDictionary d)
+			throws Exception {
+		assertEquals(TRUE, d.getBoolean("foo", TRUE));
+		assertEquals(Long.valueOf(123L), d.getLong("foo", 123L));
+		assertEquals(Integer.valueOf(123), d.getInt("foo", 123));
+		assertEquals(Double.valueOf(123D), d.getDouble("foo", 123D));
+		assertEquals("123", d.getString("foo", "123"));
+		byte[] defaultRaw = {1, 2, 3};
+		assertArrayEquals(defaultRaw, d.getRaw("foo", defaultRaw));
+		BdfList defaultList = BdfList.of(1, 2, 3);
+		assertEquals(defaultList, d.getList("foo", defaultList));
+		BdfDictionary defaultDict = BdfDictionary.of(new BdfEntry("123", 123));
+		assertEquals(defaultDict, d.getDictionary("foo", defaultDict));
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForBooleanThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getBoolean("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalBooleanThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getOptionalBoolean("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultBooleanThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getBoolean("foo", true);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForLongThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 1.23)).getLong("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalLongThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 1.23)).getOptionalLong("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultLongThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 1.23)).getLong("foo", 1L);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForIntThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 1.23)).getInt("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalIntThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 1.23)).getOptionalInt("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultIntThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 1.23)).getInt("foo", 1);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDoubleThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getDouble("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalDoubleThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getOptionalDouble("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultDoubleThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getDouble("foo", 1D);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForStringThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getString("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalStringThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getOptionalString("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultStringThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getString("foo", "");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForRawThrowsFormatException() throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getRaw("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalRawThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getOptionalRaw("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultRawThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getRaw("foo", new byte[0]);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForListThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getList("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalListThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getOptionalList("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultListThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getList("foo",
+				new BdfList());
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDictionaryThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getDictionary("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalDictionaryThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getOptionalDictionary("foo");
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultDictionaryThrowsFormatException()
+			throws Exception {
+		BdfDictionary.of(new BdfEntry("foo", 123)).getDictionary("foo",
+				new BdfDictionary());
+	}
 }

bramble-api/src/test/java/org/briarproject/bramble/api/data/BdfListTest.java

@@ -5,31 +5,31 @@ import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.test.BrambleTestCase;
 import org.junit.Test;
 
-import java.util.Arrays;
-import java.util.Collections;
-
+import static java.lang.Boolean.TRUE;
+import static java.util.Arrays.asList;
+import static java.util.Collections.emptyList;
 import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
 
 public class BdfListTest extends BrambleTestCase {
 
 	@Test
 	public void testConstructors() {
-		assertEquals(Collections.emptyList(), new BdfList());
-		assertEquals(Arrays.asList(1, 2, NULL_VALUE),
-				new BdfList(Arrays.asList(1, 2, NULL_VALUE)));
+		assertEquals(emptyList(), new BdfList());
+		assertEquals(asList(1, 2, NULL_VALUE),
+				new BdfList(asList(1, 2, NULL_VALUE)));
 	}
 
 	@Test
 	public void testFactoryMethod() {
-		assertEquals(Collections.emptyList(), BdfList.of());
-		assertEquals(Arrays.asList(1, 2, NULL_VALUE),
-				BdfList.of(1, 2, NULL_VALUE));
+		assertEquals(emptyList(), BdfList.of());
+		assertEquals(asList(1, 2, NULL_VALUE), BdfList.of(1, 2, NULL_VALUE));
 	}
 
 	@Test
-	public void testIntegerPromotion() throws Exception {
+	public void testLongPromotion() throws Exception {
 		BdfList list = new BdfList();
 		list.add((byte) 1);
 		list.add((short) 2);
@@ -41,6 +41,31 @@ public class BdfListTest extends BrambleTestCase {
 		assertEquals(Long.valueOf(4), list.getLong(3));
 	}
 
+	@Test
+	public void testIntPromotionAndDemotion() throws Exception {
+		BdfList list = new BdfList();
+		list.add((byte) 1);
+		list.add((short) 2);
+		list.add(3);
+		list.add(4L);
+		assertEquals(Integer.valueOf(1), list.getInt(0));
+		assertEquals(Integer.valueOf(2), list.getInt(1));
+		assertEquals(Integer.valueOf(3), list.getInt(2));
+		assertEquals(Integer.valueOf(4), list.getInt(3));
+	}
+
+	@Test(expected = FormatException.class)
+	public void testIntUnderflow() throws Exception {
+		BdfList list = BdfList.of(Integer.MIN_VALUE - 1L);
+		list.getInt(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testIntOverflow() throws Exception {
+		BdfList list = BdfList.of(Integer.MAX_VALUE + 1L);
+		list.getInt(0);
+	}
+
 	@Test
 	public void testFloatPromotion() throws Exception {
 		BdfList list = new BdfList();
@@ -63,61 +88,6 @@ public class BdfListTest extends BrambleTestCase {
 		assertArrayEquals(new byte[123], second);
 	}
 
-	@Test
-	@SuppressWarnings("ConstantConditions")
-	public void testIndexOutOfBoundsReturnsDefaultValue() throws Exception {
-		BdfList list = BdfList.of(1, 2, 3);
-		boolean defaultBoolean = true;
-		assertEquals(defaultBoolean, list.getBoolean(-1, defaultBoolean));
-		assertEquals(defaultBoolean, list.getBoolean(3, defaultBoolean));
-		Long defaultLong = 123L;
-		assertEquals(defaultLong, list.getLong(-1, defaultLong));
-		assertEquals(defaultLong, list.getLong(3, defaultLong));
-		Double defaultDouble = 1.23;
-		assertEquals(defaultDouble, list.getDouble(-1, defaultDouble));
-		assertEquals(defaultDouble, list.getDouble(3, defaultDouble));
-		String defaultString = "123";
-		assertEquals(defaultString, list.getString(-1, defaultString));
-		assertEquals(defaultString, list.getString(3, defaultString));
-		byte[] defaultBytes = new byte[] {1, 2, 3};
-		assertArrayEquals(defaultBytes, list.getRaw(-1, defaultBytes));
-		assertArrayEquals(defaultBytes, list.getRaw(3, defaultBytes));
-		BdfList defaultList = BdfList.of(1, 2, 3);
-		assertEquals(defaultList, list.getList(-1, defaultList));
-		assertEquals(defaultList, list.getList(3, defaultList));
-		BdfDictionary defaultDict = BdfDictionary.of(
-				new BdfEntry("1", 1),
-				new BdfEntry("2", 2),
-				new BdfEntry("3", 3)
-		);
-		assertEquals(defaultDict, list.getDictionary(-1, defaultDict));
-		assertEquals(defaultDict, list.getDictionary(3, defaultDict));
-	}
-
-	@Test
-	@SuppressWarnings("ConstantConditions")
-	public void testWrongTypeReturnsDefaultValue() throws Exception {
-		BdfList list = BdfList.of(1, 2, 3, true);
-		boolean defaultBoolean = true;
-		assertEquals(defaultBoolean, list.getBoolean(0, defaultBoolean));
-		Long defaultLong = 123L;
-		assertEquals(defaultLong, list.getLong(3, defaultLong));
-		Double defaultDouble = 1.23;
-		assertEquals(defaultDouble, list.getDouble(0, defaultDouble));
-		String defaultString = "123";
-		assertEquals(defaultString, list.getString(0, defaultString));
-		byte[] defaultBytes = new byte[] {1, 2, 3};
-		assertArrayEquals(defaultBytes, list.getRaw(0, defaultBytes));
-		BdfList defaultList = BdfList.of(1, 2, 3);
-		assertEquals(defaultList, list.getList(0, defaultList));
-		BdfDictionary defaultDict = BdfDictionary.of(
-				new BdfEntry("1", 1),
-				new BdfEntry("2", 2),
-				new BdfEntry("3", 3)
-		);
-		assertEquals(defaultDict, list.getDictionary(0, defaultDict));
-	}
-
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForBooleanThrowsFormatException()
 			throws Exception {
@@ -130,6 +100,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalBoolean(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultBooleanThrowsFormatException()
+			throws Exception {
+		new BdfList().getBoolean(-1, true);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForLongThrowsFormatException()
 			throws Exception {
@@ -142,6 +118,30 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalLong(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultLongThrowsFormatException()
+			throws Exception {
+		new BdfList().getLong(-1, 1L);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForIntThrowsFormatException()
+			throws Exception {
+		new BdfList().getInt(-1);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForOptionalIntThrowsFormatException()
+			throws Exception {
+		new BdfList().getOptionalInt(-1);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultIntThrowsFormatException()
+			throws Exception {
+		new BdfList().getInt(-1, 1);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForDoubleThrowsFormatException()
 			throws Exception {
@@ -154,6 +154,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalDouble(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultDoubleThrowsFormatException()
+			throws Exception {
+		new BdfList().getDouble(-1, 1D);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForStringThrowsFormatException()
 			throws Exception {
@@ -166,6 +172,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalString(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultStringThrowsFormatException()
+			throws Exception {
+		new BdfList().getString(-1, "");
+	}
+
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForRawThrowsFormatException()
 			throws Exception {
@@ -178,6 +190,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalRaw(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultRawThrowsFormatException()
+			throws Exception {
+		new BdfList().getRaw(-1, new byte[0]);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForListThrowsFormatException()
 			throws Exception {
@@ -190,6 +208,11 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalList(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultListThrowsFormatException()
+			throws Exception {
+		new BdfList().getList(-1, new BdfList());
+	}
 
 	@Test(expected = FormatException.class)
 	public void testNegativeIndexForDictionaryThrowsFormatException()
@@ -203,6 +226,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalDictionary(-1);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testNegativeIndexForDefaultDictionaryThrowsFormatException()
+			throws Exception {
+		new BdfList().getDictionary(-1, new BdfDictionary());
+	}
+
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForBooleanThrowsFormatException()
 			throws Exception {
@@ -215,6 +244,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalBoolean(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultBooleanThrowsFormatException()
+			throws Exception {
+		new BdfList().getBoolean(0, true);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForLongThrowsFormatException()
 			throws Exception {
@@ -227,6 +262,30 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalLong(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultLongThrowsFormatException()
+			throws Exception {
+		new BdfList().getLong(0, 1L);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForIntThrowsFormatException()
+			throws Exception {
+		new BdfList().getInt(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForOptionalIntThrowsFormatException()
+			throws Exception {
+		new BdfList().getOptionalInt(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultIntThrowsFormatException()
+			throws Exception {
+		new BdfList().getInt(0, 1);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForDoubleThrowsFormatException()
 			throws Exception {
@@ -239,6 +298,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalDouble(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultDoubleThrowsFormatException()
+			throws Exception {
+		new BdfList().getDouble(0, 1D);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForStringThrowsFormatException()
 			throws Exception {
@@ -251,6 +316,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalString(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultStringThrowsFormatException()
+			throws Exception {
+		new BdfList().getString(0, "");
+	}
+
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForRawThrowsFormatException()
 			throws Exception {
@@ -263,6 +334,12 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalRaw(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultRawThrowsFormatException()
+			throws Exception {
+		new BdfList().getRaw(0, new byte[0]);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForListThrowsFormatException()
 			throws Exception {
@@ -275,6 +352,11 @@ public class BdfListTest extends BrambleTestCase {
 		new BdfList().getOptionalList(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultListThrowsFormatException()
+			throws Exception {
+		new BdfList().getList(0, new BdfList());
+	}
 
 	@Test(expected = FormatException.class)
 	public void testTooLargeIndexForDictionaryThrowsFormatException()
@@ -287,6 +369,13 @@ public class BdfListTest extends BrambleTestCase {
 			throws Exception {
 		new BdfList().getOptionalDictionary(0);
 	}
+
+	@Test(expected = FormatException.class)
+	public void testTooLargeIndexForDefaultDictionaryThrowsFormatException()
+			throws Exception {
+		new BdfList().getDictionary(0, new BdfDictionary());
+	}
+
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForBooleanThrowsFormatException()
 			throws Exception {
@@ -299,6 +388,12 @@ public class BdfListTest extends BrambleTestCase {
 		BdfList.of(123).getOptionalBoolean(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultBooleanThrowsFormatException()
+			throws Exception {
+		BdfList.of(123).getBoolean(0, true);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForLongThrowsFormatException() throws Exception {
 		BdfList.of(1.23).getLong(0);
@@ -310,6 +405,29 @@ public class BdfListTest extends BrambleTestCase {
 		BdfList.of(1.23).getOptionalLong(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultLongThrowsFormatException()
+			throws Exception {
+		BdfList.of(1.23).getLong(0, 1L);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForIntThrowsFormatException() throws Exception {
+		BdfList.of(1.23).getInt(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForOptionalIntThrowsFormatException()
+			throws Exception {
+		BdfList.of(1.23).getOptionalInt(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultIntThrowsFormatException()
+			throws Exception {
+		BdfList.of(1.23).getInt(0, 1);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForDoubleThrowsFormatException() throws Exception {
 		BdfList.of(123).getDouble(0);
@@ -321,6 +439,12 @@ public class BdfListTest extends BrambleTestCase {
 		BdfList.of(123).getOptionalDouble(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultDoubleThrowsFormatException()
+			throws Exception {
+		BdfList.of(123).getDouble(0, 1D);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForStringThrowsFormatException() throws Exception {
 		BdfList.of(123).getString(0);
@@ -332,6 +456,12 @@ public class BdfListTest extends BrambleTestCase {
 		BdfList.of(123).getOptionalString(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultStringThrowsFormatException()
+			throws Exception {
+		BdfList.of(123).getString(0, "");
+	}
+
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForRawThrowsFormatException() throws Exception {
 		BdfList.of(123).getRaw(0);
@@ -343,6 +473,12 @@ public class BdfListTest extends BrambleTestCase {
 		BdfList.of(123).getOptionalRaw(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultRawThrowsFormatException()
+			throws Exception {
+		BdfList.of(123).getRaw(0, new byte[0]);
+	}
+
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForListThrowsFormatException() throws Exception {
 		BdfList.of(123).getList(0);
@@ -354,6 +490,11 @@ public class BdfListTest extends BrambleTestCase {
 		BdfList.of(123).getOptionalList(0);
 	}
 
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultListThrowsFormatException()
+			throws Exception {
+		BdfList.of(123).getList(0, new BdfList());
+	}
 
 	@Test(expected = FormatException.class)
 	public void testWrongTypeForDictionaryThrowsFormatException()
@@ -366,4 +507,81 @@ public class BdfListTest extends BrambleTestCase {
 			throws Exception {
 		BdfList.of(123).getOptionalDictionary(0);
 	}
+
+	@Test(expected = FormatException.class)
+	public void testWrongTypeForDefaultDictionaryThrowsFormatException()
+			throws Exception {
+		BdfList.of(123).getDictionary(0, new BdfDictionary());
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForBooleanThrowsFormatException()
+			throws Exception {
+		BdfList.of(NULL_VALUE).getBoolean(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForLongThrowsFormatException() throws Exception {
+		BdfList.of(NULL_VALUE).getLong(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForIntThrowsFormatException() throws Exception {
+		BdfList.of(NULL_VALUE).getInt(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForDoubleThrowsFormatException() throws Exception {
+		BdfList.of(NULL_VALUE).getDouble(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForStringThrowsFormatException() throws Exception {
+		BdfList.of(NULL_VALUE).getString(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForRawThrowsFormatException() throws Exception {
+		BdfList.of(NULL_VALUE).getRaw(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForListThrowsFormatException() throws Exception {
+		BdfList.of(NULL_VALUE).getList(0);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testNullValueForDictionaryThrowsFormatException()
+			throws Exception {
+		BdfList.of(NULL_VALUE).getDictionary(0);
+	}
+
+	@Test
+	public void testOptionalMethodsReturnNullForNullValue() throws Exception {
+		BdfList list = BdfList.of(NULL_VALUE);
+		assertNull(list.getOptionalBoolean(0));
+		assertNull(list.getOptionalLong(0));
+		assertNull(list.getOptionalInt(0));
+		assertNull(list.getOptionalDouble(0));
+		assertNull(list.getOptionalString(0));
+		assertNull(list.getOptionalRaw(0));
+		assertNull(list.getOptionalList(0));
+		assertNull(list.getOptionalDictionary(0));
+	}
+
+	@Test
+	public void testDefaultMethodsReturnDefaultForNullValue() throws Exception {
+		BdfList list = BdfList.of(NULL_VALUE);
+		assertEquals(TRUE, list.getBoolean(0, TRUE));
+		assertEquals(Long.valueOf(123L), list.getLong(0, 123L));
+		assertEquals(Integer.valueOf(123), list.getInt(0, 123));
+		assertEquals(Double.valueOf(123D), list.getDouble(0, 123D));
+		assertEquals("123", list.getString(0, "123"));
+		byte[] defaultRaw = {1, 2, 3};
+		assertArrayEquals(defaultRaw, list.getRaw(0, defaultRaw));
+		BdfList defaultList = BdfList.of(1, 2, 3);
+		assertEquals(defaultList, list.getList(0, defaultList));
+		BdfDictionary defaultDict = BdfDictionary.of(new BdfEntry("123", 123));
+		assertEquals(defaultDict, list.getDictionary(0, defaultDict));
+	}
 }

bramble-api/witness.gradle

@@ -4,7 +4,7 @@ dependencyVerification {
         'com.fasterxml.jackson.core:jackson-annotations:2.13.4:jackson-annotations-2.13.4.jar:ac5b27a634942391ca113850ee7db01df1499a240174021263501c05fc653b44',
         'com.google.code.findbugs:annotations:3.0.1:annotations-3.0.1.jar:6b47ff0a6de0ce17cbedc3abb0828ca5bce3009d53ea47b3723ff023c4742f79',
         'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
-        'com.google.dagger:dagger:2.43.2:dagger-2.43.2.jar:c89681f7cbbf8c527bf4ac2748515d617fdb54a1d425c08d914fdc28192b5fe4',
+        'com.google.dagger:dagger:2.45:dagger-2.45.jar:f011cae7d2c0fb7ea17c34e05bc10e768b1081a5892ad019cf1fdb0e125c49c1',
         'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
         'junit:junit:4.13.2:junit-4.13.2.jar:8e495b634469d64fb8acfa3495a065cbacc8a0fff55ce1e31007be4c16dc57d3',
         'net.bytebuddy:byte-buddy:1.9.12:byte-buddy-1.9.12.jar:3688c3d434bebc3edc5516296a2ed0f47b65e451071b4afecad84f902f0efc11',
@@ -12,8 +12,8 @@ dependencyVerification {
         'org.apache-extras.beanshell:bsh:2.0b6:bsh-2.0b6.jar:a17955976070c0573235ee662f2794a78082758b61accffce8d3f8aedcd91047',
         'org.briarproject:null-safety:0.1:null-safety-0.1.jar:161760de5e838cb982bafa973df820675d4397098e9a91637a36a306d43ba011',
         'org.codehaus.mojo.signature:java16:1.1:java16-1.1.signature:53799223a2c98dba2d0add810bed76315460df285c69e4f397ae6098f87dd619',
-        'org.codehaus.mojo:animal-sniffer-ant-tasks:1.20:animal-sniffer-ant-tasks-1.20.jar:bb7d2498144118311d968bb08ff6fae3fc535fb1cb9cca8b8e9ea65b189422ac',
-        'org.codehaus.mojo:animal-sniffer:1.20:animal-sniffer-1.20.jar:80c422523c38db91260c6d78e5ee4b012862ab61cc55020c9e243dd7b5c62249',
+        'org.codehaus.mojo:animal-sniffer-ant-tasks:1.22:animal-sniffer-ant-tasks-1.22.jar:3f6afeb3e09301d2d7179ed1db21e3ad8846c1e38415ad832a395138ae3f4218',
+        'org.codehaus.mojo:animal-sniffer:1.22:animal-sniffer-1.22.jar:f18c11a25bdd8b520b9c6a28cbb6f33007c812ab0051b6be3f0778e660aa501c',
         'org.hamcrest:hamcrest-core:2.1:hamcrest-core-2.1.jar:e09109e54a289d88506b9bfec987ddd199f4217c9464132668351b9a4f00bee9',
         'org.hamcrest:hamcrest-library:2.1:hamcrest-library-2.1.jar:b7e2b6895b3b679f0e47b6380fda391b225e9b78505db9d8bdde8d3cc8d52a21',
         'org.hamcrest:hamcrest:2.1:hamcrest-2.1.jar:ba93b2e3a562322ba432f0a1b53addcc55cb188253319a020ed77f824e692050',
@@ -24,6 +24,6 @@ dependencyVerification {
         'org.jmock:jmock:2.12.0:jmock-2.12.0.jar:266d07314c0cd343c46ff8a55601272de8cf406807caf55e6f313295f83d10be',
         'org.objenesis:objenesis:3.0.1:objenesis-3.0.1.jar:7a8ff780b9ff48415d7c705f60030b0acaa616e7f823c98eede3b63508d4e984',
         'org.ow2.asm:asm:7.1:asm-7.1.jar:4ab2fa2b6d2cc9ccb1eaa05ea329c407b47b13ed2915f62f8c4b8cc96258d4de',
-        'org.ow2.asm:asm:9.1:asm-9.1.jar:cda4de455fab48ff0bcb7c48b4639447d4de859a7afc30a094a986f0936beba2',
+        'org.ow2.asm:asm:9.3:asm-9.3.jar:1263369b59e29c943918de11d6d6152e2ec6085ce63e5710516f8c67d368e4bc',
     ]
 }

bramble-core/build.gradle

@@ -11,7 +11,7 @@ apply from: '../dagger.gradle'
 dependencies {
 	api project(':bramble-api')
 
-	api 'org.briarproject:jtorctl:0.5'
+	api "org.briarproject:onionwrapper-core:$onionwrapper_version"
 
 	implementation "org.bouncycastle:bcprov-jdk15to18:$bouncy_castle_version"
 	//noinspection GradleDependency
@@ -28,12 +28,12 @@ dependencies {
 	testImplementation project(path: ':bramble-api', configuration: 'testOutput')
 
 	testImplementation 'org.hsqldb:hsqldb:2.3.5' // The last version that supports Java 1.6
-	testImplementation 'net.jodah:concurrentunit:0.4.2'
+	testImplementation 'net.jodah:concurrentunit:0.4.6'
 	testImplementation "junit:junit:$junit_version"
 	testImplementation "org.jmock:jmock:$jmock_version"
 	testImplementation "org.jmock:jmock-junit4:$jmock_version"
 	testImplementation "org.jmock:jmock-imposters:$jmock_version"
-	testImplementation "com.squareup.okhttp3:mockwebserver:4.9.3"
+	testImplementation "com.squareup.okhttp3:mockwebserver:$mockwebserver_version"
 
 	testAnnotationProcessor "com.google.dagger:dagger-compiler:$dagger_version"
 

bramble-core/src/main/java/org/briarproject/bramble/BrambleCoreModule.java

@@ -17,6 +17,7 @@ import org.briarproject.bramble.lifecycle.LifecycleModule;
 import org.briarproject.bramble.mailbox.MailboxModule;
 import org.briarproject.bramble.plugin.PluginModule;
 import org.briarproject.bramble.properties.PropertiesModule;
+import org.briarproject.bramble.qrcode.QrCodeModule;
 import org.briarproject.bramble.record.RecordModule;
 import org.briarproject.bramble.reliability.ReliabilityModule;
 import org.briarproject.bramble.rendezvous.RendezvousModule;
@@ -47,6 +48,7 @@ import dagger.Module;
 		MailboxModule.class,
 		PluginModule.class,
 		PropertiesModule.class,
+		QrCodeModule.class,
 		RecordModule.class,
 		ReliabilityModule.class,
 		RendezvousModule.class,

bramble-core/src/main/java/org/briarproject/bramble/account/AccountManagerImpl.java

@@ -19,7 +19,6 @@ import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStreamReader;
-import java.nio.charset.Charset;
 import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
@@ -29,6 +28,7 @@ import javax.inject.Inject;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.api.crypto.DecryptionResult.INVALID_CIPHERTEXT;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.StringUtils.UTF_8;
 import static org.briarproject.bramble.util.StringUtils.fromHexString;
 import static org.briarproject.bramble.util.StringUtils.toHexString;
 
@@ -99,7 +99,7 @@ class AccountManagerImpl implements AccountManager {
 		}
 		try {
 			BufferedReader reader = new BufferedReader(new InputStreamReader(
-					new FileInputStream(f), Charset.forName("UTF-8")));
+					new FileInputStream(f), UTF_8));
 			String key = reader.readLine();
 			reader.close();
 			return key;
@@ -151,7 +151,7 @@ class AccountManagerImpl implements AccountManager {
 	@GuardedBy("stateChangeLock")
 	private void writeDbKeyToFile(String key, File f) throws IOException {
 		FileOutputStream out = new FileOutputStream(f);
-		out.write(key.getBytes(Charset.forName("UTF-8")));
+		out.write(key.getBytes(UTF_8));
 		out.flush();
 		out.close();
 	}

bramble-core/src/main/java/org/briarproject/bramble/client/ClientHelperImpl.java

@@ -155,7 +155,13 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public BdfList getMessageAsList(Transaction txn, MessageId m)
 			throws DbException, FormatException {
-		return toList(db.getMessage(txn, m).getBody());
+		return getMessageAsList(txn, m, true);
+	}
+
+	@Override
+	public BdfList getMessageAsList(Transaction txn, MessageId m,
+			boolean canonical) throws DbException, FormatException {
+		return toList(db.getMessage(txn, m), canonical);
 	}
 
 	@Override
@@ -313,8 +319,13 @@ class ClientHelperImpl implements ClientHelper {
 
 	@Override
 	public BdfList toList(byte[] b, int off, int len) throws FormatException {
+		return toList(b, off, len, true);
+	}
+
+	private BdfList toList(byte[] b, int off, int len, boolean canonical)
+			throws FormatException {
 		ByteArrayInputStream in = new ByteArrayInputStream(b, off, len);
-		BdfReader reader = bdfReaderFactory.createReader(in);
+		BdfReader reader = bdfReaderFactory.createReader(in, canonical);
 		try {
 			BdfList list = reader.readList();
 			if (!reader.eof()) throw new FormatException();
@@ -328,7 +339,7 @@ class ClientHelperImpl implements ClientHelper {
 
 	@Override
 	public BdfList toList(byte[] b) throws FormatException {
-		return toList(b, 0, b.length);
+		return toList(b, 0, b.length, true);
 	}
 
 	@Override
@@ -336,6 +347,12 @@ class ClientHelperImpl implements ClientHelper {
 		return toList(m.getBody());
 	}
 
+	@Override
+	public BdfList toList(Message m, boolean canonical) throws FormatException {
+		byte[] b = m.getBody();
+		return toList(b, 0, b.length, canonical);
+	}
+
 	@Override
 	public BdfList toList(Author a) {
 		return BdfList.of(a.getFormatVersion(), a.getName(), a.getPublicKey());
@@ -361,7 +378,7 @@ class ClientHelperImpl implements ClientHelper {
 	public Author parseAndValidateAuthor(BdfList author)
 			throws FormatException {
 		checkSize(author, 3);
-		int formatVersion = author.getLong(0).intValue();
+		int formatVersion = author.getInt(0);
 		if (formatVersion != FORMAT_VERSION) throw new FormatException();
 		String name = author.getString(1);
 		checkLength(name, 1, MAX_AUTHOR_NAME_LENGTH);
@@ -472,8 +489,7 @@ class ClientHelperImpl implements ClientHelper {
 			if (element.size() != 2) {
 				throw new FormatException();
 			}
-			list.add(new MailboxVersion(element.getLong(0).intValue(),
-					element.getLong(1).intValue()));
+			list.add(new MailboxVersion(element.getInt(0), element.getInt(1)));
 		}
 		// Sort the list of versions for easier comparison
 		sort(list);
@@ -486,7 +502,7 @@ class ClientHelperImpl implements ClientHelper {
 		try {
 			BdfDictionary meta =
 					getGroupMetadataAsDictionary(txn, contactGroupId);
-			return new ContactId(meta.getLong(GROUP_KEY_CONTACT_ID).intValue());
+			return new ContactId(meta.getInt(GROUP_KEY_CONTACT_ID));
 		} catch (FormatException e) {
 			throw new DbException(e); // Invalid group metadata
 		}

bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeManagerImpl.java

@@ -1,7 +1,6 @@
 package org.briarproject.bramble.contact;
 
 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.Predicate;
 import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactExchangeManager;
@@ -24,6 +23,7 @@ import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
+import org.briarproject.bramble.api.record.RecordReader.RecordPredicate;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
@@ -61,12 +61,12 @@ class ContactExchangeManagerImpl implements ContactExchangeManager {
 			getLogger(ContactExchangeManagerImpl.class.getName());
 
 	// Accept records with current protocol version, known record type
-	private static final Predicate<Record> ACCEPT = r ->
+	private static final RecordPredicate ACCEPT = r ->
 			r.getProtocolVersion() == PROTOCOL_VERSION &&
 					isKnownRecordType(r.getRecordType());
 
 	// Ignore records with current protocol version, unknown record type
-	private static final Predicate<Record> IGNORE = r ->
+	private static final RecordPredicate IGNORE = r ->
 			r.getProtocolVersion() == PROTOCOL_VERSION &&
 					!isKnownRecordType(r.getRecordType());
 

bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeConstants.java

@@ -5,14 +5,31 @@ import static org.briarproject.bramble.api.crypto.CryptoConstants.MAC_BYTES;
 interface HandshakeConstants {
 
 	/**
-	 * The current version of the handshake protocol.
+	 * The current major version of the handshake protocol.
 	 */
-	byte PROTOCOL_VERSION = 0;
+	byte PROTOCOL_MAJOR_VERSION = 0;
 
 	/**
-	 * Label for deriving the master key.
+	 * The current minor version of the handshake protocol.
 	 */
-	String MASTER_KEY_LABEL = "org.briarproject.bramble.handshake/MASTER_KEY";
+	byte PROTOCOL_MINOR_VERSION = 1;
+
+	/**
+	 * Label for deriving the master key when using the deprecated v0.0 key
+	 * derivation method.
+	 * <p>
+	 * TODO: Remove this after a reasonable migration period (added 2023-03-10).
+	 */
+	@Deprecated
+	String MASTER_KEY_LABEL_0_0 =
+			"org.briarproject.bramble.handshake/MASTER_KEY";
+
+	/**
+	 * Label for deriving the master key when using the v0.1 key derivation
+	 * method.
+	 */
+	String MASTER_KEY_LABEL_0_1 =
+			"org.briarproject.bramble.handshake/MASTER_KEY_0_1";
 
 	/**
 	 * Label for deriving Alice's proof of ownership from the master key.

bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeCrypto.java

@@ -13,11 +13,26 @@ interface HandshakeCrypto {
 	KeyPair generateEphemeralKeyPair();
 
 	/**
-	 * Derives the master key from the given static and ephemeral keys.
+	 * Derives the master key from the given static and ephemeral keys using
+	 * the deprecated v0.0 key derivation method.
+	 * <p>
+	 * TODO: Remove this after a reasonable migration period (added 2023-03-10).
 	 *
 	 * @param alice Whether the local peer is Alice
 	 */
-	SecretKey deriveMasterKey(PublicKey theirStaticPublicKey,
+	@Deprecated
+	SecretKey deriveMasterKey_0_0(PublicKey theirStaticPublicKey,
+			PublicKey theirEphemeralPublicKey, KeyPair ourStaticKeyPair,
+			KeyPair ourEphemeralKeyPair, boolean alice)
+			throws GeneralSecurityException;
+
+	/**
+	 * Derives the master key from the given static and ephemeral keys using
+	 * the v0.1 key derivation method.
+	 *
+	 * @param alice Whether the local peer is Alice
+	 */
+	SecretKey deriveMasterKey_0_1(PublicKey theirStaticPublicKey,
 			PublicKey theirEphemeralPublicKey, KeyPair ourStaticKeyPair,
 			KeyPair ourEphemeralKeyPair, boolean alice)
 			throws GeneralSecurityException;

bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeCryptoImpl.java

@@ -13,7 +13,8 @@ import javax.inject.Inject;
 
 import static org.briarproject.bramble.contact.HandshakeConstants.ALICE_PROOF_LABEL;
 import static org.briarproject.bramble.contact.HandshakeConstants.BOB_PROOF_LABEL;
-import static org.briarproject.bramble.contact.HandshakeConstants.MASTER_KEY_LABEL;
+import static org.briarproject.bramble.contact.HandshakeConstants.MASTER_KEY_LABEL_0_0;
+import static org.briarproject.bramble.contact.HandshakeConstants.MASTER_KEY_LABEL_0_1;
 
 @Immutable
 @NotNullByDefault
@@ -32,7 +33,8 @@ class HandshakeCryptoImpl implements HandshakeCrypto {
 	}
 
 	@Override
-	public SecretKey deriveMasterKey(PublicKey theirStaticPublicKey,
+	@Deprecated
+	public SecretKey deriveMasterKey_0_0(PublicKey theirStaticPublicKey,
 			PublicKey theirEphemeralPublicKey, KeyPair ourStaticKeyPair,
 			KeyPair ourEphemeralKeyPair, boolean alice) throws
 			GeneralSecurityException {
@@ -46,9 +48,29 @@ class HandshakeCryptoImpl implements HandshakeCrypto {
 				alice ? ourEphemeral : theirEphemeral,
 				alice ? theirEphemeral : ourEphemeral
 		};
-		return crypto.deriveSharedSecret(MASTER_KEY_LABEL, theirStaticPublicKey,
-				theirEphemeralPublicKey, ourStaticKeyPair, ourEphemeralKeyPair,
-				alice, inputs);
+		return crypto.deriveSharedSecretBadly(MASTER_KEY_LABEL_0_0,
+				theirStaticPublicKey, theirEphemeralPublicKey,
+				ourStaticKeyPair, ourEphemeralKeyPair, alice, inputs);
+	}
+
+	@Override
+	public SecretKey deriveMasterKey_0_1(PublicKey theirStaticPublicKey,
+			PublicKey theirEphemeralPublicKey, KeyPair ourStaticKeyPair,
+			KeyPair ourEphemeralKeyPair, boolean alice) throws
+			GeneralSecurityException {
+		byte[] theirStatic = theirStaticPublicKey.getEncoded();
+		byte[] theirEphemeral = theirEphemeralPublicKey.getEncoded();
+		byte[] ourStatic = ourStaticKeyPair.getPublic().getEncoded();
+		byte[] ourEphemeral = ourEphemeralKeyPair.getPublic().getEncoded();
+		byte[][] inputs = {
+				alice ? ourStatic : theirStatic,
+				alice ? theirStatic : ourStatic,
+				alice ? ourEphemeral : theirEphemeral,
+				alice ? theirEphemeral : ourEphemeral
+		};
+		return crypto.deriveSharedSecret(MASTER_KEY_LABEL_0_1,
+				theirStaticPublicKey, theirEphemeralPublicKey,
+				ourStaticKeyPair, ourEphemeralKeyPair, alice, inputs);
 	}
 
 	@Override

bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeManagerImpl.java

@@ -2,7 +2,6 @@ package org.briarproject.bramble.contact;
 
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.Pair;
-import org.briarproject.bramble.api.Predicate;
 import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.contact.HandshakeManager;
 import org.briarproject.bramble.api.contact.PendingContact;
@@ -12,12 +11,12 @@ import org.briarproject.bramble.api.crypto.KeyPair;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.crypto.TransportCrypto;
-import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.TransactionManager;
 import org.briarproject.bramble.api.identity.IdentityManager;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
+import org.briarproject.bramble.api.record.RecordReader.RecordPredicate;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
@@ -28,15 +27,20 @@ import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.security.GeneralSecurityException;
+import java.util.List;
 
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
+import static java.util.Arrays.asList;
+import static java.util.Collections.singletonList;
 import static org.briarproject.bramble.api.crypto.CryptoConstants.MAX_AGREEMENT_PUBLIC_KEY_BYTES;
 import static org.briarproject.bramble.contact.HandshakeConstants.PROOF_BYTES;
-import static org.briarproject.bramble.contact.HandshakeConstants.PROTOCOL_VERSION;
-import static org.briarproject.bramble.contact.HandshakeRecordTypes.EPHEMERAL_PUBLIC_KEY;
-import static org.briarproject.bramble.contact.HandshakeRecordTypes.PROOF_OF_OWNERSHIP;
+import static org.briarproject.bramble.contact.HandshakeConstants.PROTOCOL_MAJOR_VERSION;
+import static org.briarproject.bramble.contact.HandshakeConstants.PROTOCOL_MINOR_VERSION;
+import static org.briarproject.bramble.contact.HandshakeRecordTypes.RECORD_TYPE_EPHEMERAL_PUBLIC_KEY;
+import static org.briarproject.bramble.contact.HandshakeRecordTypes.RECORD_TYPE_MINOR_VERSION;
+import static org.briarproject.bramble.contact.HandshakeRecordTypes.RECORD_TYPE_PROOF_OF_OWNERSHIP;
 import static org.briarproject.bramble.util.ValidationUtils.checkLength;
 
 @Immutable
@@ -44,12 +48,14 @@ import static org.briarproject.bramble.util.ValidationUtils.checkLength;
 class HandshakeManagerImpl implements HandshakeManager {
 
 	// Ignore records with current protocol version, unknown record type
-	private static final Predicate<Record> IGNORE = r ->
-			r.getProtocolVersion() == PROTOCOL_VERSION &&
+	private static final RecordPredicate IGNORE = r ->
+			r.getProtocolVersion() == PROTOCOL_MAJOR_VERSION &&
 					!isKnownRecordType(r.getRecordType());
 
 	private static boolean isKnownRecordType(byte type) {
-		return type == EPHEMERAL_PUBLIC_KEY || type == PROOF_OF_OWNERSHIP;
+		return type == RECORD_TYPE_EPHEMERAL_PUBLIC_KEY ||
+				type == RECORD_TYPE_PROOF_OF_OWNERSHIP ||
+				type == RECORD_TYPE_MINOR_VERSION;
 	}
 
 	private final TransactionManager db;
@@ -61,7 +67,7 @@ class HandshakeManagerImpl implements HandshakeManager {
 	private final RecordWriterFactory recordWriterFactory;
 
 	@Inject
-	HandshakeManagerImpl(DatabaseComponent db,
+	HandshakeManagerImpl(TransactionManager db,
 			IdentityManager identityManager,
 			ContactManager contactManager,
 			TransportCrypto transportCrypto,
@@ -95,19 +101,31 @@ class HandshakeManagerImpl implements HandshakeManager {
 				.createRecordWriter(out.getOutputStream());
 		KeyPair ourEphemeralKeyPair =
 				handshakeCrypto.generateEphemeralKeyPair();
-		PublicKey theirEphemeralPublicKey;
+		Pair<Byte, PublicKey> theirMinorVersionAndKey;
 		if (alice) {
+			sendMinorVersion(recordWriter);
 			sendPublicKey(recordWriter, ourEphemeralKeyPair.getPublic());
-			theirEphemeralPublicKey = receivePublicKey(recordReader);
+			theirMinorVersionAndKey = receiveMinorVersionAndKey(recordReader);
 		} else {
-			theirEphemeralPublicKey = receivePublicKey(recordReader);
+			theirMinorVersionAndKey = receiveMinorVersionAndKey(recordReader);
+			sendMinorVersion(recordWriter);
 			sendPublicKey(recordWriter, ourEphemeralKeyPair.getPublic());
 		}
+		byte theirMinorVersion = theirMinorVersionAndKey.getFirst();
+		PublicKey theirEphemeralPublicKey = theirMinorVersionAndKey.getSecond();
 		SecretKey masterKey;
 		try {
-			masterKey = handshakeCrypto.deriveMasterKey(theirStaticPublicKey,
-					theirEphemeralPublicKey, ourStaticKeyPair,
-					ourEphemeralKeyPair, alice);
+			if (theirMinorVersion > 0) {
+				masterKey = handshakeCrypto.deriveMasterKey_0_1(
+						theirStaticPublicKey, theirEphemeralPublicKey,
+						ourStaticKeyPair, ourEphemeralKeyPair, alice);
+			} else {
+				// TODO: Remove this branch after a reasonable migration
+				//  period (added 2023-03-10).
+				masterKey = handshakeCrypto.deriveMasterKey_0_0(
+						theirStaticPublicKey, theirEphemeralPublicKey,
+						ourStaticKeyPair, ourEphemeralKeyPair, alice);
+			}
 		} catch (GeneralSecurityException e) {
 			throw new FormatException();
 		}
@@ -128,34 +146,91 @@ class HandshakeManagerImpl implements HandshakeManager {
 	}
 
 	private void sendPublicKey(RecordWriter w, PublicKey k) throws IOException {
-		w.writeRecord(new Record(PROTOCOL_VERSION, EPHEMERAL_PUBLIC_KEY,
-				k.getEncoded()));
+		w.writeRecord(new Record(PROTOCOL_MAJOR_VERSION,
+				RECORD_TYPE_EPHEMERAL_PUBLIC_KEY, k.getEncoded()));
 		w.flush();
 	}
 
-	private PublicKey receivePublicKey(RecordReader r) throws IOException {
-		byte[] key = readRecord(r, EPHEMERAL_PUBLIC_KEY).getPayload();
+	/**
+	 * Receives the remote peer's protocol minor version and ephemeral public
+	 * key.
+	 * <p>
+	 * In version 0.1 of the protocol, each peer sends a minor version record
+	 * followed by an ephemeral public key record.
+	 * <p>
+	 * In version 0.0 of the protocol, each peer sends an ephemeral public key
+	 * record without a preceding minor version record.
+	 * <p>
+	 * Therefore the remote peer's minor version must be non-zero if a minor
+	 * version record is received, and is assumed to be zero if no minor
+	 * version record is received.
+	 */
+	private Pair<Byte, PublicKey> receiveMinorVersionAndKey(RecordReader r)
+			throws IOException {
+		byte theirMinorVersion;
+		PublicKey theirEphemeralPublicKey;
+		// The first record can be either a minor version record or an
+		// ephemeral public key record
+		Record first = readRecord(r, asList(RECORD_TYPE_MINOR_VERSION,
+				RECORD_TYPE_EPHEMERAL_PUBLIC_KEY));
+		if (first.getRecordType() == RECORD_TYPE_MINOR_VERSION) {
+			// The payload must be a single byte giving the remote peer's
+			// protocol minor version, which must be non-zero
+			byte[] payload = first.getPayload();
+			checkLength(payload, 1);
+			theirMinorVersion = payload[0];
+			if (theirMinorVersion == 0) throw new FormatException();
+			// The second record must be an ephemeral public key record
+			Record second = readRecord(r,
+					singletonList(RECORD_TYPE_EPHEMERAL_PUBLIC_KEY));
+			theirEphemeralPublicKey = parsePublicKey(second);
+		} else {
+			// The remote peer did not send a minor version record, so the
+			// remote peer's protocol minor version is assumed to be zero
+			// TODO: Remove this branch after a reasonable migration period
+			//  (added 2023-03-10).
+			theirMinorVersion = 0;
+			theirEphemeralPublicKey = parsePublicKey(first);
+		}
+		return new Pair<>(theirMinorVersion, theirEphemeralPublicKey);
+	}
+
+	private PublicKey parsePublicKey(Record rec) throws IOException {
+		if (rec.getRecordType() != RECORD_TYPE_EPHEMERAL_PUBLIC_KEY) {
+			throw new AssertionError();
+		}
+		byte[] key = rec.getPayload();
 		checkLength(key, 1, MAX_AGREEMENT_PUBLIC_KEY_BYTES);
 		return new AgreementPublicKey(key);
 	}
 
 	private void sendProof(RecordWriter w, byte[] proof) throws IOException {
-		w.writeRecord(new Record(PROTOCOL_VERSION, PROOF_OF_OWNERSHIP, proof));
+		w.writeRecord(new Record(PROTOCOL_MAJOR_VERSION,
+				RECORD_TYPE_PROOF_OF_OWNERSHIP, proof));
 		w.flush();
 	}
 
 	private byte[] receiveProof(RecordReader r) throws IOException {
-		byte[] proof = readRecord(r, PROOF_OF_OWNERSHIP).getPayload();
+		Record rec = readRecord(r,
+				singletonList(RECORD_TYPE_PROOF_OF_OWNERSHIP));
+		byte[] proof = rec.getPayload();
 		checkLength(proof, PROOF_BYTES, PROOF_BYTES);
 		return proof;
 	}
 
-	private Record readRecord(RecordReader r, byte expectedType)
+	private void sendMinorVersion(RecordWriter w) throws IOException {
+		w.writeRecord(new Record(PROTOCOL_MAJOR_VERSION,
+				RECORD_TYPE_MINOR_VERSION,
+				new byte[] {PROTOCOL_MINOR_VERSION}));
+		w.flush();
+	}
+
+	private Record readRecord(RecordReader r, List<Byte> expectedTypes)
 			throws IOException {
-		// Accept records with current protocol version, expected type only
-		Predicate<Record> accept = rec ->
-				rec.getProtocolVersion() == PROTOCOL_VERSION &&
-						rec.getRecordType() == expectedType;
+		// Accept records with current protocol version, expected types only
+		RecordPredicate accept = rec ->
+				rec.getProtocolVersion() == PROTOCOL_MAJOR_VERSION &&
+						expectedTypes.contains(rec.getRecordType());
 		Record rec = r.readRecord(accept, IGNORE);
 		if (rec == null) throw new EOFException();
 		return rec;

bramble-core/src/main/java/org/briarproject/bramble/contact/HandshakeRecordTypes.java

@@ -5,7 +5,9 @@ package org.briarproject.bramble.contact;
  */
 interface HandshakeRecordTypes {
 
-	byte EPHEMERAL_PUBLIC_KEY = 0;
+	byte RECORD_TYPE_EPHEMERAL_PUBLIC_KEY = 0;
 
-	byte PROOF_OF_OWNERSHIP = 1;
+	byte RECORD_TYPE_PROOF_OF_OWNERSHIP = 1;
+
+	byte RECORD_TYPE_MINOR_VERSION = 2;
 }

bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoComponentImpl.java

@@ -29,12 +29,12 @@ import org.briarproject.nullsafety.NotNullByDefault;
 import org.whispersystems.curve25519.Curve25519;
 import org.whispersystems.curve25519.Curve25519KeyPair;
 
-import java.nio.charset.Charset;
 import java.security.GeneralSecurityException;
 import java.security.NoSuchAlgorithmException;
 import java.security.Provider;
 import java.security.SecureRandom;
 import java.security.Security;
+import java.util.Locale;
 import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
@@ -51,6 +51,7 @@ import static org.briarproject.bramble.api.crypto.DecryptionResult.KEY_STRENGTHE
 import static org.briarproject.bramble.util.ByteUtils.INT_32_BYTES;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.now;
+import static org.briarproject.bramble.util.StringUtils.US_ASCII;
 
 @NotNullByDefault
 class CryptoComponentImpl implements CryptoComponent {
@@ -222,7 +223,8 @@ class CryptoComponentImpl implements CryptoComponent {
 	}
 
 	@Override
-	public SecretKey deriveSharedSecret(String label,
+	@Deprecated
+	public SecretKey deriveSharedSecretBadly(String label,
 			PublicKey theirStaticPublicKey, PublicKey theirEphemeralPublicKey,
 			KeyPair ourStaticKeyPair, KeyPair ourEphemeralKeyPair,
 			boolean alice, byte[]... inputs) throws GeneralSecurityException {
@@ -250,6 +252,35 @@ class CryptoComponentImpl implements CryptoComponent {
 		return new SecretKey(hash);
 	}
 
+	@Override
+	public SecretKey deriveSharedSecret(String label,
+			PublicKey theirStaticPublicKey, PublicKey theirEphemeralPublicKey,
+			KeyPair ourStaticKeyPair, KeyPair ourEphemeralKeyPair,
+			boolean alice, byte[]... inputs) throws GeneralSecurityException {
+		PrivateKey ourStaticPrivateKey = ourStaticKeyPair.getPrivate();
+		PrivateKey ourEphemeralPrivateKey = ourEphemeralKeyPair.getPrivate();
+		byte[][] hashInputs = new byte[inputs.length + 3][];
+		// Alice ephemeral/Bob ephemeral
+		hashInputs[0] = performRawKeyAgreement(ourEphemeralPrivateKey,
+				theirEphemeralPublicKey);
+		// Alice static/Bob ephemeral, Bob static/Alice ephemeral
+		if (alice) {
+			hashInputs[1] = performRawKeyAgreement(ourStaticPrivateKey,
+					theirEphemeralPublicKey);
+			hashInputs[2] = performRawKeyAgreement(ourEphemeralPrivateKey,
+					theirStaticPublicKey);
+		} else {
+			hashInputs[1] = performRawKeyAgreement(ourEphemeralPrivateKey,
+					theirStaticPublicKey);
+			hashInputs[2] = performRawKeyAgreement(ourStaticPrivateKey,
+					theirEphemeralPublicKey);
+		}
+		arraycopy(inputs, 0, hashInputs, 3, inputs.length);
+		byte[] hash = hash(label, hashInputs);
+		if (hash.length != SecretKey.LENGTH) throw new IllegalStateException();
+		return new SecretKey(hash);
+	}
+
 	@Override
 	public byte[] sign(String label, byte[] toSign, PrivateKey privateKey)
 			throws GeneralSecurityException {
@@ -460,7 +491,7 @@ class CryptoComponentImpl implements CryptoComponent {
 	@Override
 	public String encodeOnion(byte[] publicKey) {
 		Digest digest = new SHA3Digest(256);
-		byte[] label = ".onion checksum".getBytes(Charset.forName("US-ASCII"));
+		byte[] label = ".onion checksum".getBytes(US_ASCII);
 		digest.update(label, 0, label.length);
 		digest.update(publicKey, 0, publicKey.length);
 		digest.update(ONION_HS_PROTOCOL_VERSION);
@@ -470,7 +501,7 @@ class CryptoComponentImpl implements CryptoComponent {
 		arraycopy(publicKey, 0, address, 0, publicKey.length);
 		arraycopy(checksum, 0, address, publicKey.length, ONION_CHECKSUM_BYTES);
 		address[address.length - 1] = ONION_HS_PROTOCOL_VERSION;
-		return Base32.encode(address).toLowerCase();
+		return Base32.encode(address).toLowerCase(Locale.US);
 	}
 
 }

bramble-core/src/main/java/org/briarproject/bramble/crypto/MessageEncrypter.java

@@ -39,12 +39,13 @@ import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.PrintStream;
-import java.nio.charset.Charset;
 import java.security.SecureRandom;
 import java.util.Scanner;
 
 import javax.annotation.concurrent.Immutable;
 
+import static org.briarproject.bramble.util.StringUtils.UTF_8;
+
 @Immutable
 @NotNullByDefault
 public class MessageEncrypter {
@@ -228,7 +229,7 @@ public class MessageEncrypter {
 		PublicKey publicKey =
 				encrypter.getKeyParser().parsePublicKey(keyBytes);
 		String message = readFully(System.in);
-		byte[] plaintext = message.getBytes(Charset.forName("UTF-8"));
+		byte[] plaintext = message.getBytes(UTF_8);
 		byte[] ciphertext = encrypter.encrypt(publicKey, plaintext);
 		System.out.println(AsciiArmour.wrap(ciphertext, LINE_LENGTH));
 	}
@@ -242,7 +243,7 @@ public class MessageEncrypter {
 				encrypter.getKeyParser().parsePrivateKey(keyBytes);
 		byte[] ciphertext = AsciiArmour.unwrap(readFully(System.in));
 		byte[] plaintext = encrypter.decrypt(privateKey, ciphertext);
-		System.out.println(new String(plaintext, Charset.forName("UTF-8")));
+		System.out.println(new String(plaintext, UTF_8));
 	}
 
 	private static String readFully(InputStream in) throws IOException {

bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderFactoryImpl.java

@@ -18,12 +18,18 @@ class BdfReaderFactoryImpl implements BdfReaderFactory {
 	@Override
 	public BdfReader createReader(InputStream in) {
 		return new BdfReaderImpl(in, DEFAULT_NESTED_LIMIT,
-				DEFAULT_MAX_BUFFER_SIZE);
+				DEFAULT_MAX_BUFFER_SIZE, true);
+	}
+
+	@Override
+	public BdfReader createReader(InputStream in, boolean canonical) {
+		return new BdfReaderImpl(in, DEFAULT_NESTED_LIMIT,
+				DEFAULT_MAX_BUFFER_SIZE, canonical);
 	}
 
 	@Override
 	public BdfReader createReader(InputStream in, int nestedLimit,
-			int maxBufferSize) {
-		return new BdfReaderImpl(in, nestedLimit, maxBufferSize);
+			int maxBufferSize, boolean canonical) {
+		return new BdfReaderImpl(in, nestedLimit, maxBufferSize, canonical);
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderImpl.java

@@ -33,21 +33,24 @@ import static org.briarproject.bramble.util.StringUtils.fromUtf8;
 
 @NotThreadSafe
 @NotNullByDefault
-class BdfReaderImpl implements BdfReader {
+final class BdfReaderImpl implements BdfReader {
 
 	private static final byte[] EMPTY_BUFFER = new byte[0];
 
 	private final InputStream in;
 	private final int nestedLimit, maxBufferSize;
+	private final boolean canonical;
 
 	private boolean hasLookahead = false, eof = false;
 	private byte next;
 	private byte[] buf = new byte[8];
 
-	BdfReaderImpl(InputStream in, int nestedLimit, int maxBufferSize) {
+	BdfReaderImpl(InputStream in, int nestedLimit, int maxBufferSize,
+			boolean canonical) {
 		this.in = in;
 		this.nestedLimit = nestedLimit;
 		this.maxBufferSize = maxBufferSize;
+		this.canonical = canonical;
 	}
 
 	private void readLookahead() throws IOException {
@@ -188,13 +191,22 @@ class BdfReaderImpl implements BdfReader {
 
 	private short readInt16() throws IOException {
 		readIntoBuffer(2);
-		return (short) (((buf[0] & 0xFF) << 8) + (buf[1] & 0xFF));
+		short value = (short) (((buf[0] & 0xFF) << 8) + (buf[1] & 0xFF));
+		if (canonical && value >= Byte.MIN_VALUE && value <= Byte.MAX_VALUE) {
+			// Value could have been encoded as an INT_8
+			throw new FormatException();
+		}
+		return value;
 	}
 
 	private int readInt32() throws IOException {
 		readIntoBuffer(4);
 		int value = 0;
 		for (int i = 0; i < 4; i++) value |= (buf[i] & 0xFF) << (24 - i * 8);
+		if (canonical && value >= Short.MIN_VALUE && value <= Short.MAX_VALUE) {
+			// Value could have been encoded as an INT_16
+			throw new FormatException();
+		}
 		return value;
 	}
 
@@ -202,6 +214,11 @@ class BdfReaderImpl implements BdfReader {
 		readIntoBuffer(8);
 		long value = 0;
 		for (int i = 0; i < 8; i++) value |= (buf[i] & 0xFFL) << (56 - i * 8);
+		if (canonical && value >= Integer.MIN_VALUE &&
+				value <= Integer.MAX_VALUE) {
+			// Value could have been encoded as an INT_32
+			throw new FormatException();
+		}
 		return value;
 	}
 
@@ -215,6 +232,31 @@ class BdfReaderImpl implements BdfReader {
 		hasLookahead = false;
 	}
 
+	@Override
+	public boolean hasInt() throws IOException {
+		if (!hasLookahead) readLookahead();
+		if (eof) return false;
+		return next == INT_8 || next == INT_16 || next == INT_32;
+	}
+
+	@Override
+	public int readInt() throws IOException {
+		if (!hasInt()) throw new FormatException();
+		hasLookahead = false;
+		if (next == INT_8) return readInt8();
+		if (next == INT_16) return readInt16();
+		return readInt32();
+	}
+
+	@Override
+	public void skipInt() throws IOException {
+		if (!hasInt()) throw new FormatException();
+		if (next == INT_8) skip(1);
+		else if (next == INT_16) skip(2);
+		else skip(4);
+		hasLookahead = false;
+	}
+
 	@Override
 	public boolean hasDouble() throws IOException {
 		if (!hasLookahead) readLookahead();
@@ -323,22 +365,11 @@ class BdfReaderImpl implements BdfReader {
 	private BdfList readList(int level) throws IOException {
 		if (!hasList()) throw new FormatException();
 		if (level > nestedLimit) throw new FormatException();
-		BdfList list = new BdfList();
-		readListStart();
-		while (!hasListEnd()) list.add(readObject(level + 1));
-		readListEnd();
-		return list;
-	}
-
-	@Override
-	public void readListStart() throws IOException {
-		if (!hasList()) throw new FormatException();
 		hasLookahead = false;
-	}
-
-	@Override
-	public boolean hasListEnd() throws IOException {
-		return hasEnd();
+		BdfList list = new BdfList();
+		while (!hasEnd()) list.add(readObject(level + 1));
+		readEnd();
+		return list;
 	}
 
 	private boolean hasEnd() throws IOException {
@@ -347,11 +378,6 @@ class BdfReaderImpl implements BdfReader {
 		return next == END;
 	}
 
-	@Override
-	public void readListEnd() throws IOException {
-		readEnd();
-	}
-
 	private void readEnd() throws IOException {
 		if (!hasEnd()) throw new FormatException();
 		hasLookahead = false;
@@ -361,7 +387,7 @@ class BdfReaderImpl implements BdfReader {
 	public void skipList() throws IOException {
 		if (!hasList()) throw new FormatException();
 		hasLookahead = false;
-		while (!hasListEnd()) skipObject();
+		while (!hasEnd()) skipObject();
 		hasLookahead = false;
 	}
 
@@ -380,35 +406,27 @@ class BdfReaderImpl implements BdfReader {
 	private BdfDictionary readDictionary(int level) throws IOException {
 		if (!hasDictionary()) throw new FormatException();
 		if (level > nestedLimit) throw new FormatException();
-		BdfDictionary dictionary = new BdfDictionary();
-		readDictionaryStart();
-		while (!hasDictionaryEnd())
-			dictionary.put(readString(), readObject(level + 1));
-		readDictionaryEnd();
-		return dictionary;
-	}
-
-	@Override
-	public void readDictionaryStart() throws IOException {
-		if (!hasDictionary()) throw new FormatException();
 		hasLookahead = false;
-	}
-
-	@Override
-	public boolean hasDictionaryEnd() throws IOException {
-		return hasEnd();
-	}
-
-	@Override
-	public void readDictionaryEnd() throws IOException {
+		BdfDictionary dictionary = new BdfDictionary();
+		String prevKey = null;
+		while (!hasEnd()) {
+			String key = readString();
+			if (canonical && prevKey != null && key.compareTo(prevKey) <= 0) {
+				// Keys not unique and sorted
+				throw new FormatException();
+			}
+			dictionary.put(key, readObject(level + 1));
+			prevKey = key;
+		}
 		readEnd();
+		return dictionary;
 	}
 
 	@Override
 	public void skipDictionary() throws IOException {
 		if (!hasDictionary()) throw new FormatException();
 		hasLookahead = false;
-		while (!hasDictionaryEnd()) {
+		while (!hasEnd()) {
 			skipString();
 			skipObject();
 		}

bramble-core/src/main/java/org/briarproject/bramble/data/BdfWriterImpl.java

@@ -2,11 +2,13 @@ package org.briarproject.bramble.data;
 
 import org.briarproject.bramble.api.Bytes;
 import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfWriter;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.IOException;
 import java.io.OutputStream;
+import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
@@ -15,6 +17,7 @@ import java.util.Map.Entry;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.NotThreadSafe;
 
+import static java.util.Collections.sort;
 import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
 import static org.briarproject.bramble.data.Types.DICTIONARY;
 import static org.briarproject.bramble.data.Types.END;
@@ -33,10 +36,11 @@ import static org.briarproject.bramble.data.Types.STRING_16;
 import static org.briarproject.bramble.data.Types.STRING_32;
 import static org.briarproject.bramble.data.Types.STRING_8;
 import static org.briarproject.bramble.data.Types.TRUE;
+import static org.briarproject.bramble.util.StringUtils.UTF_8;
 
 @NotThreadSafe
 @NotNullByDefault
-class BdfWriterImpl implements BdfWriter {
+final class BdfWriterImpl implements BdfWriter {
 
 	private final OutputStream out;
 
@@ -113,7 +117,7 @@ class BdfWriterImpl implements BdfWriter {
 
 	@Override
 	public void writeString(String s) throws IOException {
-		byte[] b = s.getBytes("UTF-8");
+		byte[] b = s.getBytes(UTF_8);
 		if (b.length <= Byte.MAX_VALUE) {
 			out.write(STRING_8);
 			out.write((byte) b.length);
@@ -161,39 +165,33 @@ class BdfWriterImpl implements BdfWriter {
 		else if (o instanceof String) writeString((String) o);
 		else if (o instanceof byte[]) writeRaw((byte[]) o);
 		else if (o instanceof Bytes) writeRaw(((Bytes) o).getBytes());
-		else if (o instanceof List) writeList((List) o);
-		else if (o instanceof Map) writeDictionary((Map) o);
+		else if (o instanceof List) writeList((List<?>) o);
+		else if (o instanceof Map) writeDictionary((Map<?, ?>) o);
 		else throw new FormatException();
 	}
 
-	@Override
-	public void writeListStart() throws IOException {
-		out.write(LIST);
-	}
-
-	@Override
-	public void writeListEnd() throws IOException {
-		out.write(END);
-	}
-
 	@Override
 	public void writeDictionary(Map<?, ?> m) throws IOException {
 		out.write(DICTIONARY);
-		for (Entry<?, ?> e : m.entrySet()) {
-			if (!(e.getKey() instanceof String)) throw new FormatException();
-			writeString((String) e.getKey());
-			writeObject(e.getValue());
+		if (m instanceof BdfDictionary) {
+			// Entries are already sorted and keys are known to be strings
+			for (Entry<String, Object> e : ((BdfDictionary) m).entrySet()) {
+				writeString(e.getKey());
+				writeObject(e.getValue());
+			}
+		} else {
+			// Check that keys are strings, write entries in canonical order
+			List<String> keys = new ArrayList<>(m.size());
+			for (Object k : m.keySet()) {
+				if (!(k instanceof String)) throw new FormatException();
+				keys.add((String) k);
+			}
+			sort(keys);
+			for (String key : keys) {
+				writeString(key);
+				writeObject(m.get(key));
+			}
 		}
 		out.write(END);
 	}
-
-	@Override
-	public void writeDictionaryStart() throws IOException {
-		out.write(DICTIONARY);
-	}
-
-	@Override
-	public void writeDictionaryEnd() throws IOException {
-		out.write(END);
-	}
 }

bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementModule.java

@@ -1,7 +1,5 @@
 package org.briarproject.bramble.keyagreement;
 
-import org.briarproject.bramble.api.data.BdfReaderFactory;
-import org.briarproject.bramble.api.data.BdfWriterFactory;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementTask;
 import org.briarproject.bramble.api.keyagreement.PayloadEncoder;
 import org.briarproject.bramble.api.keyagreement.PayloadParser;
@@ -19,13 +17,13 @@ public class KeyAgreementModule {
 	}
 
 	@Provides
-	PayloadEncoder providePayloadEncoder(BdfWriterFactory bdfWriterFactory) {
-		return new PayloadEncoderImpl(bdfWriterFactory);
+	PayloadEncoder providePayloadEncoder(PayloadEncoderImpl payloadEncoder) {
+		return payloadEncoder;
 	}
 
 	@Provides
-	PayloadParser providePayloadParser(BdfReaderFactory bdfReaderFactory) {
-		return new PayloadParserImpl(bdfReaderFactory);
+	PayloadParser providePayloadParser(PayloadParserImpl payloadParser) {
+		return payloadParser;
 	}
 
 	@Provides

bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTransport.java

@@ -1,11 +1,11 @@
 package org.briarproject.bramble.keyagreement;
 
-import org.briarproject.bramble.api.Predicate;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
+import org.briarproject.bramble.api.record.RecordReader.RecordPredicate;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
@@ -34,12 +34,12 @@ class KeyAgreementTransport {
 			Logger.getLogger(KeyAgreementTransport.class.getName());
 
 	// Accept records with current protocol version, known record type
-	private static final Predicate<Record> ACCEPT = r ->
+	private static final RecordPredicate ACCEPT = r ->
 			r.getProtocolVersion() == PROTOCOL_VERSION &&
 					isKnownRecordType(r.getRecordType());
 
 	// Ignore records with current protocol version, unknown record type
-	private static final Predicate<Record> IGNORE = r ->
+	private static final RecordPredicate IGNORE = r ->
 			r.getProtocolVersion() == PROTOCOL_VERSION &&
 					!isKnownRecordType(r.getRecordType());
 

bramble-core/src/main/java/org/briarproject/bramble/keyagreement/PayloadEncoderImpl.java

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.keyagreement;
 
+import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.BdfWriter;
 import org.briarproject.bramble.api.data.BdfWriterFactory;
 import org.briarproject.bramble.api.keyagreement.Payload;
@@ -13,7 +14,8 @@ import java.io.IOException;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
-import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.PROTOCOL_VERSION;
+import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.QR_FORMAT_ID;
+import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.QR_FORMAT_VERSION;
 
 @Immutable
 @NotNullByDefault
@@ -29,14 +31,16 @@ class PayloadEncoderImpl implements PayloadEncoder {
 	@Override
 	public byte[] encode(Payload p) {
 		ByteArrayOutputStream out = new ByteArrayOutputStream();
-		out.write(PROTOCOL_VERSION);
+		int formatIdAndVersion = (QR_FORMAT_ID << 5) | QR_FORMAT_VERSION;
+		out.write(formatIdAndVersion);
+		BdfList payload = new BdfList();
+		payload.add(p.getCommitment());
+		for (TransportDescriptor d : p.getTransportDescriptors()) {
+			payload.add(d.getDescriptor());
+		}
 		BdfWriter w = bdfWriterFactory.createWriter(out);
 		try {
-			w.writeListStart(); // Payload start
-			w.writeRaw(p.getCommitment());
-			for (TransportDescriptor d : p.getTransportDescriptors())
-				w.writeList(d.getDescriptor());
-			w.writeListEnd(); // Payload end
+			w.writeList(payload);
 		} catch (IOException e) {
 			// Shouldn't happen with ByteArrayOutputStream
 			throw new AssertionError(e);

bramble-core/src/main/java/org/briarproject/bramble/keyagreement/PayloadParserImpl.java

@@ -1,6 +1,7 @@
 package org.briarproject.bramble.keyagreement;
 
 import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.Pair;
 import org.briarproject.bramble.api.UnsupportedVersionException;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.BdfReader;
@@ -11,6 +12,9 @@ import org.briarproject.bramble.api.keyagreement.TransportDescriptor;
 import org.briarproject.bramble.api.plugin.BluetoothConstants;
 import org.briarproject.bramble.api.plugin.LanTcpConstants;
 import org.briarproject.bramble.api.plugin.TransportId;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType;
+import org.briarproject.bramble.api.qrcode.WrongQrCodeTypeException;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.ByteArrayInputStream;
@@ -21,34 +25,42 @@ import java.util.List;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
-import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.BETA_PROTOCOL_VERSION;
 import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.COMMIT_LENGTH;
-import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.PROTOCOL_VERSION;
+import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.QR_FORMAT_VERSION;
 import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.TRANSPORT_ID_BLUETOOTH;
 import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.TRANSPORT_ID_LAN;
+import static org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType.BQP;
+import static org.briarproject.bramble.util.StringUtils.ISO_8859_1;
 
 @Immutable
 @NotNullByDefault
 class PayloadParserImpl implements PayloadParser {
 
 	private final BdfReaderFactory bdfReaderFactory;
+	private final QrCodeClassifier qrCodeClassifier;
 
 	@Inject
-	PayloadParserImpl(BdfReaderFactory bdfReaderFactory) {
+	PayloadParserImpl(BdfReaderFactory bdfReaderFactory,
+			QrCodeClassifier qrCodeClassifier) {
 		this.bdfReaderFactory = bdfReaderFactory;
+		this.qrCodeClassifier = qrCodeClassifier;
 	}
 
 	@Override
-	public Payload parse(byte[] raw) throws IOException {
-		ByteArrayInputStream in = new ByteArrayInputStream(raw);
-		// First byte: the protocol version
-		int protocolVersion = in.read();
-		if (protocolVersion == -1) throw new FormatException();
-		if (protocolVersion != PROTOCOL_VERSION) {
-			boolean tooOld = protocolVersion < PROTOCOL_VERSION ||
-					protocolVersion == BETA_PROTOCOL_VERSION;
+	public Payload parse(String payloadString) throws IOException {
+		Pair<QrCodeType, Integer> typeAndVersion =
+				qrCodeClassifier.classifyQrCode(payloadString);
+		QrCodeType qrCodeType = typeAndVersion.getFirst();
+		if (qrCodeType != BQP) throw new WrongQrCodeTypeException(qrCodeType);
+		int formatVersion = typeAndVersion.getSecond();
+		if (formatVersion != QR_FORMAT_VERSION) {
+			boolean tooOld = formatVersion < QR_FORMAT_VERSION;
 			throw new UnsupportedVersionException(tooOld);
 		}
+		byte[] raw = payloadString.getBytes(ISO_8859_1);
+		ByteArrayInputStream in = new ByteArrayInputStream(raw);
+		// First byte: the format identifier and version (already parsed)
+		if (in.read() == -1) throw new AssertionError();
 		// The rest of the payload is a BDF list with one or more elements
 		BdfReader r = bdfReaderFactory.createReader(in);
 		BdfList payload = r.readList();
@@ -61,7 +73,7 @@ class PayloadParserImpl implements PayloadParser {
 		List<TransportDescriptor> recognised = new ArrayList<>();
 		for (int i = 1; i < payload.size(); i++) {
 			BdfList descriptor = payload.getList(i);
-			long transportId = descriptor.getLong(0);
+			int transportId = descriptor.getInt(0);
 			if (transportId == TRANSPORT_ID_BLUETOOTH) {
 				TransportId id = BluetoothConstants.ID;
 				recognised.add(new TransportDescriptor(id, descriptor));

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxManagerImpl.java

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.mailbox;
 
+import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.db.TransactionManager;
@@ -11,12 +12,15 @@ import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxStatus;
 import org.briarproject.bramble.api.mailbox.MailboxVersion;
 import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.bramble.util.Base32;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.IOException;
 import java.util.List;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.GuardedBy;
@@ -26,6 +30,7 @@ import javax.inject.Inject;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.StringUtils.ISO_8859_1;
 
 @Immutable
 @NotNullByDefault
@@ -98,6 +103,22 @@ class MailboxManagerImpl implements MailboxManager {
 		return created;
 	}
 
+	@Override
+	public String convertBase32Payload(String base32Payload)
+			throws FormatException {
+		Pattern regex = Pattern.compile("(briar-mailbox://)?([a-z2-7]{104})");
+		Matcher matcher = regex.matcher(base32Payload);
+		if (!matcher.find()) throw new FormatException();
+		String base32 = matcher.group(2);
+		byte[] payloadBytes;
+		try {
+			payloadBytes = Base32.decode(base32, false);
+		} catch (IllegalArgumentException e) {
+			throw new FormatException();
+		}
+		return new String(payloadBytes, ISO_8859_1);
+	}
+
 	@Override
 	public boolean checkConnection() {
 		List<MailboxVersion> versions = null;

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxModule.java

@@ -1,6 +1,5 @@
 package org.briarproject.bramble.mailbox;
 
-import org.briarproject.bramble.api.FeatureFlags;
 import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.data.MetadataEncoder;
@@ -76,14 +75,11 @@ public class MailboxModule {
 			ValidationManager validationManager,
 			ClientHelper clientHelper,
 			MetadataEncoder metadataEncoder,
-			Clock clock,
-			FeatureFlags featureFlags) {
+			Clock clock) {
 		MailboxUpdateValidator validator = new MailboxUpdateValidator(
 				clientHelper, metadataEncoder, clock);
-		if (featureFlags.shouldEnableMailbox()) {
-			validationManager.registerMessageValidator(CLIENT_ID,
-					MAJOR_VERSION, validator);
-		}
+		validationManager.registerMessageValidator(CLIENT_ID, MAJOR_VERSION,
+				validator);
 		return validator;
 	}
 
@@ -95,31 +91,26 @@ public class MailboxModule {
 	@Provides
 	@Singleton
 	MailboxUpdateManager provideMailboxUpdateManager(
-			FeatureFlags featureFlags,
 			LifecycleManager lifecycleManager,
 			ValidationManager validationManager, ContactManager contactManager,
 			ClientVersioningManager clientVersioningManager,
 			MailboxSettingsManager mailboxSettingsManager,
 			MailboxUpdateManagerImpl mailboxUpdateManager) {
-		if (featureFlags.shouldEnableMailbox()) {
-			lifecycleManager.registerOpenDatabaseHook(mailboxUpdateManager);
-			validationManager.registerIncomingMessageHook(CLIENT_ID,
-					MAJOR_VERSION, mailboxUpdateManager);
-			contactManager.registerContactHook(mailboxUpdateManager);
-			clientVersioningManager.registerClient(CLIENT_ID, MAJOR_VERSION,
-					MINOR_VERSION, mailboxUpdateManager);
-			mailboxSettingsManager.registerMailboxHook(mailboxUpdateManager);
-		}
+		lifecycleManager.registerOpenDatabaseHook(mailboxUpdateManager);
+		validationManager.registerIncomingMessageHook(CLIENT_ID, MAJOR_VERSION,
+				mailboxUpdateManager);
+		contactManager.registerContactHook(mailboxUpdateManager);
+		clientVersioningManager.registerClient(CLIENT_ID, MAJOR_VERSION,
+				MINOR_VERSION, mailboxUpdateManager);
+		mailboxSettingsManager.registerMailboxHook(mailboxUpdateManager);
 		return mailboxUpdateManager;
 	}
 
 	@Provides
 	@Singleton
-	MailboxFileManager provideMailboxFileManager(FeatureFlags featureFlags,
-			EventBus eventBus, MailboxFileManagerImpl mailboxFileManager) {
-		if (featureFlags.shouldEnableMailbox()) {
-			eventBus.addListener(mailboxFileManager);
-		}
+	MailboxFileManager provideMailboxFileManager(EventBus eventBus,
+			MailboxFileManagerImpl mailboxFileManager) {
+		eventBus.addListener(mailboxFileManager);
 		return mailboxFileManager;
 	}
 
@@ -160,17 +151,14 @@ public class MailboxModule {
 			MailboxUpdateManager mailboxUpdateManager,
 			MailboxClientFactory mailboxClientFactory,
 			TorReachabilityMonitor reachabilityMonitor,
-			FeatureFlags featureFlags,
 			LifecycleManager lifecycleManager,
 			EventBus eventBus) {
 		MailboxClientManager manager = new MailboxClientManager(eventExecutor,
 				dbExecutor, db, contactManager, pluginManager,
 				mailboxSettingsManager, mailboxUpdateManager,
 				mailboxClientFactory, reachabilityMonitor);
-		if (featureFlags.shouldEnableMailbox()) {
-			lifecycleManager.registerService(manager);
-			eventBus.addListener(manager);
-		}
+		lifecycleManager.registerService(manager);
+		eventBus.addListener(manager);
 		return manager;
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskFactoryImpl.java

@@ -6,6 +6,7 @@ import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxPairingTask;
 import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateManager;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.nullsafety.NotNullByDefault;
 
@@ -25,6 +26,7 @@ class MailboxPairingTaskFactoryImpl implements MailboxPairingTaskFactory {
 	private final MailboxApi api;
 	private final MailboxSettingsManager mailboxSettingsManager;
 	private final MailboxUpdateManager mailboxUpdateManager;
+	private final QrCodeClassifier qrCodeClassifier;
 
 	@Inject
 	MailboxPairingTaskFactoryImpl(
@@ -34,7 +36,8 @@ class MailboxPairingTaskFactoryImpl implements MailboxPairingTaskFactory {
 			Clock clock,
 			MailboxApi api,
 			MailboxSettingsManager mailboxSettingsManager,
-			MailboxUpdateManager mailboxUpdateManager) {
+			MailboxUpdateManager mailboxUpdateManager,
+			QrCodeClassifier qrCodeClassifier) {
 		this.eventExecutor = eventExecutor;
 		this.db = db;
 		this.crypto = crypto;
@@ -42,12 +45,13 @@ class MailboxPairingTaskFactoryImpl implements MailboxPairingTaskFactory {
 		this.api = api;
 		this.mailboxSettingsManager = mailboxSettingsManager;
 		this.mailboxUpdateManager = mailboxUpdateManager;
+		this.qrCodeClassifier = qrCodeClassifier;
 	}
 
 	@Override
 	public MailboxPairingTask createPairingTask(String qrCodePayload) {
 		return new MailboxPairingTaskImpl(qrCodePayload, eventExecutor, db,
 				crypto, clock, api, mailboxSettingsManager,
-				mailboxUpdateManager);
+				mailboxUpdateManager, qrCodeClassifier);
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxPairingTaskImpl.java

@@ -2,6 +2,7 @@ package org.briarproject.bramble.mailbox;
 
 import org.briarproject.bramble.api.Consumer;
 import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.Pair;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.db.DatabaseComponent;
@@ -9,18 +10,26 @@ import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.mailbox.MailboxAuthToken;
 import org.briarproject.bramble.api.mailbox.MailboxPairingState;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.ConnectionError;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.InvalidQrCode;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.MailboxAlreadyPaired;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.Paired;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.Pairing;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.QrCodeReceived;
+import org.briarproject.bramble.api.mailbox.MailboxPairingState.UnexpectedError;
 import org.briarproject.bramble.api.mailbox.MailboxPairingTask;
 import org.briarproject.bramble.api.mailbox.MailboxProperties;
 import org.briarproject.bramble.api.mailbox.MailboxSettingsManager;
 import org.briarproject.bramble.api.mailbox.MailboxUpdate;
 import org.briarproject.bramble.api.mailbox.MailboxUpdateManager;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.mailbox.MailboxApi.ApiException;
 import org.briarproject.bramble.mailbox.MailboxApi.MailboxAlreadyPairedException;
 import org.briarproject.nullsafety.NotNullByDefault;
 
 import java.io.IOException;
-import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -32,7 +41,10 @@ import javax.annotation.concurrent.ThreadSafe;
 
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.api.mailbox.MailboxConstants.QR_FORMAT_VERSION;
+import static org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType.MAILBOX;
 import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.StringUtils.ISO_8859_1;
 
 @ThreadSafe
 @NotNullByDefault
@@ -40,9 +52,6 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 
 	private final static Logger LOG =
 			getLogger(MailboxPairingTaskImpl.class.getName());
-	@SuppressWarnings("CharsetObjectCanBeUsed") // Requires minSdkVersion >= 19
-	private static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1");
-	private static final int VERSION_REQUIRED = 32;
 
 	private final String payload;
 	private final Executor eventExecutor;
@@ -52,6 +61,8 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 	private final MailboxApi api;
 	private final MailboxSettingsManager mailboxSettingsManager;
 	private final MailboxUpdateManager mailboxUpdateManager;
+	private final QrCodeClassifier qrCodeClassifier;
+	private final long timeStarted;
 
 	private final Object lock = new Object();
 	@GuardedBy("lock")
@@ -68,7 +79,8 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 			Clock clock,
 			MailboxApi api,
 			MailboxSettingsManager mailboxSettingsManager,
-			MailboxUpdateManager mailboxUpdateManager) {
+			MailboxUpdateManager mailboxUpdateManager,
+			QrCodeClassifier qrCodeClassifier) {
 		this.payload = payload;
 		this.eventExecutor = eventExecutor;
 		this.db = db;
@@ -77,7 +89,9 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 		this.api = api;
 		this.mailboxSettingsManager = mailboxSettingsManager;
 		this.mailboxUpdateManager = mailboxUpdateManager;
-		state = new MailboxPairingState.QrCodeReceived();
+		this.qrCodeClassifier = qrCodeClassifier;
+		timeStarted = clock.currentTimeMillis();
+		state = new QrCodeReceived(timeStarted);
 	}
 
 	@Override
@@ -99,22 +113,30 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 
 	@Override
 	public void run() {
+		Pair<QrCodeType, Integer> typeAndVersion =
+				qrCodeClassifier.classifyQrCode(payload);
+		QrCodeType qrCodeType = typeAndVersion.getFirst();
+		int formatVersion = typeAndVersion.getSecond();
+		if (qrCodeType != MAILBOX || formatVersion != QR_FORMAT_VERSION) {
+			setState(new InvalidQrCode(qrCodeType, formatVersion));
+			return;
+		}
 		try {
 			pairMailbox();
 		} catch (FormatException e) {
-			onMailboxError(e, new MailboxPairingState.InvalidQrCode());
+			onMailboxError(e, new InvalidQrCode(qrCodeType, formatVersion));
 		} catch (MailboxAlreadyPairedException e) {
-			onMailboxError(e, new MailboxPairingState.MailboxAlreadyPaired());
+			onMailboxError(e, new MailboxAlreadyPaired());
 		} catch (IOException e) {
-			onMailboxError(e, new MailboxPairingState.ConnectionError());
+			onMailboxError(e, new ConnectionError());
 		} catch (ApiException | DbException e) {
-			onMailboxError(e, new MailboxPairingState.UnexpectedError());
+			onMailboxError(e, new UnexpectedError());
 		}
 	}
 
 	private void pairMailbox() throws IOException, ApiException, DbException {
 		MailboxProperties mailboxProperties = decodeQrCodePayload(payload);
-		setState(new MailboxPairingState.Pairing());
+		setState(new Pairing(timeStarted));
 		MailboxProperties ownerProperties = api.setup(mailboxProperties);
 		long time = clock.currentTimeMillis();
 		db.transaction(false, txn -> {
@@ -133,7 +155,7 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 				}
 			}
 		});
-		setState(new MailboxPairingState.Paired());
+		setState(new Paired());
 	}
 
 	private void onMailboxError(Exception e, MailboxPairingState state) {
@@ -167,14 +189,6 @@ class MailboxPairingTaskImpl implements MailboxPairingTask {
 			}
 			throw new FormatException();
 		}
-		int version = bytes[0] & 0xFF;
-		if (version != VERSION_REQUIRED) {
-			if (LOG.isLoggable(WARNING)) {
-				LOG.warning("QR code has not version " + VERSION_REQUIRED +
-						": " + version);
-			}
-			throw new FormatException();
-		}
 		LOG.info("QR code is valid");
 		byte[] onionPubKey = Arrays.copyOfRange(bytes, 1, 33);
 		String onion = crypto.encodeOnion(onionPubKey);

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

@@ -40,9 +40,9 @@ import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicReference;
 import java.util.logging.Logger;
 
+import javax.annotation.concurrent.GuardedBy;
 import javax.annotation.concurrent.ThreadSafe;
 import javax.inject.Inject;
 
@@ -288,8 +288,10 @@ class PluginManagerImpl implements PluginManager, Service {
 	private class Callback implements PluginCallback {
 
 		private final TransportId id;
-		private final AtomicReference<State> state =
-				new AtomicReference<>(STARTING_STOPPING);
+		private final Object stateLock = new Object();
+
+		@GuardedBy("lock")
+		private State state = STARTING_STOPPING;
 
 		private Callback(TransportId id) {
 			this.id = id;
@@ -343,22 +345,26 @@ class PluginManagerImpl implements PluginManager, Service {
 
 		@Override
 		public void pluginStateChanged(State newState) {
-			State oldState = state.getAndSet(newState);
-			if (newState != oldState) {
-				if (LOG.isLoggable(INFO)) {
-					LOG.info(id + " changed from state " + oldState
-							+ " to " + newState);
+			synchronized (stateLock) {
+				if (newState != state) {
+					State oldState = state;
+					state = newState;
+					if (LOG.isLoggable(INFO)) {
+						LOG.info(id + " changed from state " + oldState
+								+ " to " + newState);
+					}
+					eventBus.broadcast(new TransportStateEvent(id, newState));
+					if (newState == ACTIVE) {
+						eventBus.broadcast(new TransportActiveEvent(id));
+					} else if (oldState == ACTIVE) {
+						eventBus.broadcast(new TransportInactiveEvent(id));
+					}
+				} else if (newState == DISABLED) {
+					// Broadcast an event even though the state hasn't changed,
+					// as the reasons for the plugin being disabled may have
+					// changed
+					eventBus.broadcast(new TransportStateEvent(id, newState));
 				}
-				eventBus.broadcast(new TransportStateEvent(id, newState));
-				if (newState == ACTIVE) {
-					eventBus.broadcast(new TransportActiveEvent(id));
-				} else if (oldState == ACTIVE) {
-					eventBus.broadcast(new TransportInactiveEvent(id));
-				}
-			} else if (newState == DISABLED) {
-				// Broadcast an event even though the state hasn't changed, as
-				// the reasons for the plugin being disabled may have changed
-				eventBus.broadcast(new TransportStateEvent(id, newState));
 			}
 		}
 

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

@@ -419,7 +419,7 @@ class LanTcpPlugin extends TcpPlugin {
 	private InetSocketAddress parseSocketAddress(BdfList descriptor)
 			throws FormatException {
 		byte[] address = descriptor.getRaw(1);
-		int port = descriptor.getLong(2).intValue();
+		int port = descriptor.getInt(2);
 		if (port < 1 || port > MAX_16_BIT_UNSIGNED) throw new FormatException();
 		try {
 			InetAddress addr = InetAddress.getByAddress(address);

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/CircumventionModule.java

@@ -1,5 +1,8 @@
 package org.briarproject.bramble.plugin.tor;
 
+import org.briarproject.onionwrapper.CircumventionProvider;
+import org.briarproject.onionwrapper.CircumventionProviderFactory;
+
 import javax.inject.Singleton;
 
 import dagger.Module;
@@ -10,8 +13,7 @@ public class CircumventionModule {
 
 	@Provides
 	@Singleton
-	CircumventionProvider provideCircumventionProvider(
-			CircumventionProviderImpl provider) {
-		return provider;
+	CircumventionProvider provideCircumventionProvider() {
+		return CircumventionProviderFactory.createCircumventionProvider();
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/CircumventionProvider.java

@@ -1,75 +0,0 @@
-package org.briarproject.bramble.plugin.tor;
-
-import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.util.List;
-
-@NotNullByDefault
-public interface CircumventionProvider {
-
-	enum BridgeType {
-		DEFAULT_OBFS4,
-		NON_DEFAULT_OBFS4,
-		VANILLA,
-		MEEK,
-		SNOWFLAKE
-	}
-
-	/**
-	 * Countries where Tor is blocked, i.e. vanilla Tor connection won't work.
-	 * <p>
-	 * See https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2
-	 * and https://trac.torproject.org/projects/tor/wiki/doc/OONI/censorshipwiki
-	 */
-	String[] BLOCKED = {"BY", "CN", "EG", "IR", "RU", "TM", "VE"};
-
-	/**
-	 * Countries where bridge connections are likely to work.
-	 * Should be a subset of {@link #BLOCKED} and the union of
-	 * {@link #DEFAULT_BRIDGES}, {@link #NON_DEFAULT_BRIDGES} and
-	 * {@link #DPI_BRIDGES}.
-	 */
-	String[] BRIDGES = {"BY", "CN", "EG", "IR", "RU", "TM", "VE"};
-
-	/**
-	 * Countries where default obfs4 or vanilla bridges are likely to work.
-	 * Should be a subset of {@link #BRIDGES}.
-	 */
-	String[] DEFAULT_BRIDGES = {"EG", "VE"};
-
-	/**
-	 * Countries where non-default obfs4 or vanilla bridges are likely to work.
-	 * Should be a subset of {@link #BRIDGES}.
-	 */
-	String[] NON_DEFAULT_BRIDGES = {"BY", "RU"};
-
-	/**
-	 * Countries where vanilla bridges are blocked via DPI but non-default
-	 * obfs4 bridges, meek and snowflake may work. Should be a subset of
-	 * {@link #BRIDGES}.
-	 */
-	String[] DPI_BRIDGES = {"CN", "IR", "TM"};
-
-	/**
-	 * Returns true if vanilla Tor connections are blocked in the given country.
-	 */
-	boolean isTorProbablyBlocked(String countryCode);
-
-	/**
-	 * Returns true if bridge connections of some type work in the given
-	 * country.
-	 */
-	boolean doBridgesWork(String countryCode);
-
-	/**
-	 * Returns the types of bridge connection that are suitable for the given
-	 * country, or {@link #DEFAULT_BRIDGES} if no bridge type is known
-	 * to work.
-	 */
-	List<BridgeType> getSuitableBridgeTypes(String countryCode);
-
-	@IoExecutor
-	List<String> getBridges(BridgeType type, String countryCode,
-			boolean letsEncrypt);
-}

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/CircumventionProviderImpl.java

@@ -1,129 +0,0 @@
-package org.briarproject.bramble.plugin.tor;
-
-import org.briarproject.bramble.api.lifecycle.IoExecutor;
-import org.briarproject.nullsafety.NotNullByDefault;
-
-import java.io.InputStream;
-import java.util.ArrayList;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Scanner;
-import java.util.Set;
-import java.util.TreeMap;
-
-import javax.annotation.concurrent.Immutable;
-import javax.inject.Inject;
-
-import static java.util.Arrays.asList;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.DEFAULT_OBFS4;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.MEEK;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.NON_DEFAULT_OBFS4;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.SNOWFLAKE;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.VANILLA;
-import static org.briarproject.nullsafety.NullSafety.requireNonNull;
-
-@Immutable
-@NotNullByDefault
-class CircumventionProviderImpl implements CircumventionProvider {
-
-	private final static String BRIDGE_FILE_NAME = "bridges";
-	private final static String SNOWFLAKE_PARAMS_FILE_NAME = "snowflake-params";
-	private final static String DEFAULT_COUNTRY_CODE = "ZZ";
-
-	private static final Set<String> BLOCKED_IN_COUNTRIES =
-			new HashSet<>(asList(BLOCKED));
-	private static final Set<String> BRIDGE_COUNTRIES =
-			new HashSet<>(asList(BRIDGES));
-	private static final Set<String> DEFAULT_OBFS4_BRIDGE_COUNTRIES =
-			new HashSet<>(asList(DEFAULT_BRIDGES));
-	private static final Set<String> NON_DEFAULT_BRIDGE_COUNTRIES =
-			new HashSet<>(asList(NON_DEFAULT_BRIDGES));
-	private static final Set<String> DPI_COUNTRIES =
-			new HashSet<>(asList(DPI_BRIDGES));
-
-	@Inject
-	CircumventionProviderImpl() {
-	}
-
-	@Override
-	public boolean isTorProbablyBlocked(String countryCode) {
-		return BLOCKED_IN_COUNTRIES.contains(countryCode);
-	}
-
-	@Override
-	public boolean doBridgesWork(String countryCode) {
-		return BRIDGE_COUNTRIES.contains(countryCode);
-	}
-
-	@Override
-	public List<BridgeType> getSuitableBridgeTypes(String countryCode) {
-		if (DEFAULT_OBFS4_BRIDGE_COUNTRIES.contains(countryCode)) {
-			return asList(DEFAULT_OBFS4, VANILLA);
-		} else if (NON_DEFAULT_BRIDGE_COUNTRIES.contains(countryCode)) {
-			return asList(NON_DEFAULT_OBFS4, VANILLA);
-		} else if (DPI_COUNTRIES.contains(countryCode)) {
-			return asList(NON_DEFAULT_OBFS4, MEEK, SNOWFLAKE);
-		} else {
-			return asList(DEFAULT_OBFS4, VANILLA);
-		}
-	}
-
-	@Override
-	@IoExecutor
-	public List<String> getBridges(BridgeType type, String countryCode,
-			boolean letsEncrypt) {
-		InputStream is = requireNonNull(getClass().getClassLoader()
-				.getResourceAsStream(BRIDGE_FILE_NAME));
-		Scanner scanner = new Scanner(is);
-
-		List<String> bridges = new ArrayList<>();
-		while (scanner.hasNextLine()) {
-			String line = scanner.nextLine();
-			if ((type == DEFAULT_OBFS4 && line.startsWith("d ")) ||
-					(type == NON_DEFAULT_OBFS4 && line.startsWith("n ")) ||
-					(type == VANILLA && line.startsWith("v ")) ||
-					(type == MEEK && line.startsWith("m "))) {
-				bridges.add(line.substring(2));
-			} else if (type == SNOWFLAKE && line.startsWith("s ")) {
-				String params = getSnowflakeParams(countryCode, letsEncrypt);
-				bridges.add(line.substring(2) + " " + params);
-			}
-		}
-		scanner.close();
-		return bridges;
-	}
-
-	// Package access for testing
-	@SuppressWarnings("WeakerAccess")
-	String getSnowflakeParams(String countryCode, boolean letsEncrypt) {
-		Map<String, String> params = loadSnowflakeParams();
-		if (countryCode.isEmpty()) countryCode = DEFAULT_COUNTRY_CODE;
-		// If we have parameters for this country code, return them
-		String value = params.get(makeKey(countryCode, letsEncrypt));
-		if (value != null) return value;
-		// Return the default parameters
-		value = params.get(makeKey(DEFAULT_COUNTRY_CODE, letsEncrypt));
-		return requireNonNull(value);
-	}
-
-	private Map<String, String> loadSnowflakeParams() {
-		InputStream is = requireNonNull(getClass().getClassLoader()
-				.getResourceAsStream(SNOWFLAKE_PARAMS_FILE_NAME));
-		Scanner scanner = new Scanner(is);
-		Map<String, String> params = new TreeMap<>();
-		while (scanner.hasNextLine()) {
-			String line = scanner.nextLine();
-			if (line.length() < 5) continue;
-			String key = line.substring(0, 4); // Country code, space, digit
-			String value = line.substring(5);
-			params.put(key, value);
-		}
-		scanner.close();
-		return params;
-	}
-
-	private String makeKey(String countryCode, boolean letsEncrypt) {
-		return countryCode + " " + (letsEncrypt ? "1" : "0");
-	}
-}

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/TorPlugin.java

@@ -1,8 +1,5 @@
 package org.briarproject.bramble.plugin.tor;
 
-import net.freehaven.tor.control.EventHandler;
-import net.freehaven.tor.control.TorControlConnection;
-
 import org.briarproject.bramble.PoliteExecutor;
 import org.briarproject.bramble.api.Pair;
 import org.briarproject.bramble.api.battery.BatteryManager;
@@ -27,36 +24,27 @@ import org.briarproject.bramble.api.rendezvous.KeyMaterialSource;
 import org.briarproject.bramble.api.rendezvous.RendezvousEndpoint;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.settings.event.SettingsUpdatedEvent;
-import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.api.system.ResourceProvider;
-import org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType;
-import org.briarproject.nullsafety.MethodsNotNullByDefault;
+import org.briarproject.nullsafety.InterfaceNotNullByDefault;
 import org.briarproject.nullsafety.NotNullByDefault;
-import org.briarproject.nullsafety.ParametersNotNullByDefault;
+import org.briarproject.onionwrapper.CircumventionProvider;
+import org.briarproject.onionwrapper.CircumventionProvider.BridgeType;
+import org.briarproject.onionwrapper.LocationUtils;
+import org.briarproject.onionwrapper.TorWrapper;
+import org.briarproject.onionwrapper.TorWrapper.HiddenServiceProperties;
+import org.briarproject.onionwrapper.TorWrapper.Observer;
+import org.briarproject.onionwrapper.TorWrapper.TorState;
 
-import java.io.ByteArrayInputStream;
-import java.io.EOFException;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
 import java.net.Socket;
-import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
-import java.util.Map;
-import java.util.Scanner;
 import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.logging.Logger;
 import java.util.regex.Pattern;
-import java.util.zip.ZipInputStream;
 
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.GuardedBy;
@@ -65,13 +53,9 @@ import javax.net.SocketFactory;
 
 import static java.util.Arrays.asList;
 import static java.util.Collections.emptyList;
-import static java.util.Collections.singletonList;
-import static java.util.Collections.singletonMap;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
 import static java.util.logging.Logger.getLogger;
-import static net.freehaven.tor.control.TorControlCommands.HS_ADDRESS;
-import static net.freehaven.tor.control.TorControlCommands.HS_PRIVKEY;
 import static org.briarproject.bramble.api.plugin.Plugin.State.ACTIVE;
 import static org.briarproject.bramble.api.plugin.Plugin.State.DISABLED;
 import static org.briarproject.bramble.api.plugin.Plugin.State.ENABLING;
@@ -93,34 +77,19 @@ import static org.briarproject.bramble.api.plugin.TorConstants.PROP_ONION_V3;
 import static org.briarproject.bramble.api.plugin.TorConstants.REASON_BATTERY;
 import static org.briarproject.bramble.api.plugin.TorConstants.REASON_COUNTRY_BLOCKED;
 import static org.briarproject.bramble.api.plugin.TorConstants.REASON_MOBILE_DATA;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.MEEK;
-import static org.briarproject.bramble.plugin.tor.CircumventionProvider.BridgeType.SNOWFLAKE;
 import static org.briarproject.bramble.plugin.tor.TorRendezvousCrypto.SEED_BYTES;
-import static org.briarproject.bramble.util.IoUtils.copyAndClose;
 import static org.briarproject.bramble.util.IoUtils.tryToClose;
 import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.PrivacyUtils.scrubOnion;
 import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
+import static org.briarproject.onionwrapper.CircumventionProvider.BridgeType.MEEK;
+import static org.briarproject.onionwrapper.CircumventionProvider.BridgeType.SNOWFLAKE;
 
-@MethodsNotNullByDefault
-@ParametersNotNullByDefault
-abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
+@InterfaceNotNullByDefault
+class TorPlugin implements DuplexPlugin, EventListener {
 
 	protected static final Logger LOG = getLogger(TorPlugin.class.getName());
 
-	private static final String[] EVENTS = {
-			"CIRC",
-			"ORCONN",
-			"STATUS_GENERAL",
-			"STATUS_CLIENT",
-			"HS_DESC",
-			"NOTICE",
-			"WARN",
-			"ERR"
-	};
-	private static final String OWNER = "__OwningControllerProcess";
-	private static final int COOKIE_TIMEOUT_MS = 3000;
-	private static final int COOKIE_POLLING_INTERVAL_MS = 200;
 	private static final Pattern ONION_V3 = Pattern.compile("[a-z2-7]{56}");
 
 	protected final Executor ioExecutor;
@@ -129,91 +98,79 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	private final NetworkManager networkManager;
 	private final LocationUtils locationUtils;
 	private final SocketFactory torSocketFactory;
-	private final Clock clock;
+	private final CircumventionProvider circumventionProvider;
 	private final BatteryManager batteryManager;
 	private final Backoff backoff;
 	private final TorRendezvousCrypto torRendezvousCrypto;
+	private final TorWrapper tor;
 	private final PluginCallback callback;
-	private final String architecture;
-	private final CircumventionProvider circumventionProvider;
-	private final ResourceProvider resourceProvider;
 	private final long maxLatency;
 	private final int maxIdleTime;
+	private final boolean canVerifyLetsEncryptCerts;
 	private final int socketTimeout;
-	private final File torDirectory, geoIpFile, configFile;
-	private final int torSocksPort;
-	private final int torControlPort;
-	private final File doneFile, cookieFile;
 	private final AtomicBoolean used = new AtomicBoolean(false);
 
 	protected final PluginState state = new PluginState();
 
-	private volatile Socket controlSocket = null;
-	private volatile TorControlConnection controlConnection = null;
 	private volatile Settings settings = null;
 
-	protected abstract int getProcessId();
-
-	protected abstract long getLastUpdateTime();
-
 	TorPlugin(Executor ioExecutor,
 			Executor wakefulIoExecutor,
 			NetworkManager networkManager,
 			LocationUtils locationUtils,
 			SocketFactory torSocketFactory,
-			Clock clock,
-			ResourceProvider resourceProvider,
 			CircumventionProvider circumventionProvider,
 			BatteryManager batteryManager,
 			Backoff backoff,
 			TorRendezvousCrypto torRendezvousCrypto,
+			TorWrapper tor,
 			PluginCallback callback,
-			String architecture,
 			long maxLatency,
 			int maxIdleTime,
-			File torDirectory,
-			int torSocksPort,
-			int torControlPort) {
+			boolean canVerifyLetsEncryptCerts) {
 		this.ioExecutor = ioExecutor;
 		this.wakefulIoExecutor = wakefulIoExecutor;
 		this.networkManager = networkManager;
 		this.locationUtils = locationUtils;
 		this.torSocketFactory = torSocketFactory;
-		this.clock = clock;
-		this.resourceProvider = resourceProvider;
 		this.circumventionProvider = circumventionProvider;
 		this.batteryManager = batteryManager;
 		this.backoff = backoff;
 		this.torRendezvousCrypto = torRendezvousCrypto;
+		this.tor = tor;
 		this.callback = callback;
-		this.architecture = architecture;
 		this.maxLatency = maxLatency;
 		this.maxIdleTime = maxIdleTime;
-		if (maxIdleTime > Integer.MAX_VALUE / 2)
+		this.canVerifyLetsEncryptCerts = canVerifyLetsEncryptCerts;
+		if (maxIdleTime > Integer.MAX_VALUE / 2) {
 			socketTimeout = Integer.MAX_VALUE;
-		else socketTimeout = maxIdleTime * 2;
-		this.torDirectory = torDirectory;
-		this.torSocksPort = torSocksPort;
-		this.torControlPort = torControlPort;
-		geoIpFile = new File(torDirectory, "geoip");
-		configFile = new File(torDirectory, "torrc");
-		doneFile = new File(torDirectory, "done");
-		cookieFile = new File(torDirectory, ".tor/control_auth_cookie");
+		} else {
+			socketTimeout = maxIdleTime * 2;
+		}
 		// Don't execute more than one connection status check at a time
 		connectionStatusExecutor =
 				new PoliteExecutor("TorPlugin", ioExecutor, 1);
-	}
+		tor.setObserver(new Observer() {
 
-	protected File getTorExecutableFile() {
-		return new File(torDirectory, "tor");
-	}
+			@Override
+			public void onState(TorState torState) {
+				State s = state.getState(torState);
+				if (s == ACTIVE) backoff.reset();
+				callback.pluginStateChanged(s);
+			}
 
-	protected File getObfs4ExecutableFile() {
-		return new File(torDirectory, "obfs4proxy");
-	}
+			@Override
+			public void onBootstrapPercentage(int percentage) {
+			}
 
-	protected File getSnowflakeExecutableFile() {
-		return new File(torDirectory, "snowflake");
+			@Override
+			public void onHsDescriptorUpload(String onion) {
+			}
+
+			@Override
+			public void onClockSkewDetected(long skewSeconds) {
+			}
+		});
 	}
 
 	@Override
@@ -234,89 +191,18 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	@Override
 	public void start() throws PluginException {
 		if (used.getAndSet(true)) throw new IllegalStateException();
-		if (!torDirectory.exists()) {
-			if (!torDirectory.mkdirs()) {
-				LOG.warning("Could not create Tor directory.");
-				throw new PluginException();
-			}
-		}
 		// Load the settings
 		settings = callback.getSettings();
+		// Start Tor
 		try {
-			// Install or update the assets if necessary
-			if (!assetsAreUpToDate()) installAssets();
-			// Start from the default config every time
-			extract(getConfigInputStream(), configFile);
-		} catch (IOException e) {
-			throw new PluginException(e);
-		}
-		if (cookieFile.exists() && !cookieFile.delete())
-			LOG.warning("Old auth cookie not deleted");
-		// Start a new Tor process
-		LOG.info("Starting Tor");
-		File torFile = getTorExecutableFile();
-		String torPath = torFile.getAbsolutePath();
-		String configPath = configFile.getAbsolutePath();
-		String pid = String.valueOf(getProcessId());
-		Process torProcess;
-		ProcessBuilder pb =
-				new ProcessBuilder(torPath, "-f", configPath, OWNER, pid);
-		Map<String, String> env = pb.environment();
-		env.put("HOME", torDirectory.getAbsolutePath());
-		pb.directory(torDirectory);
-		pb.redirectErrorStream(true);
-		try {
-			torProcess = pb.start();
-		} catch (SecurityException | IOException e) {
-			throw new PluginException(e);
-		}
-		try {
-			// Wait for the Tor process to start
-			waitForTorToStart(torProcess);
-			// Wait for the auth cookie file to be created/updated
-			long start = clock.currentTimeMillis();
-			while (cookieFile.length() < 32) {
-				if (clock.currentTimeMillis() - start > COOKIE_TIMEOUT_MS) {
-					LOG.warning("Auth cookie not created");
-					if (LOG.isLoggable(INFO)) listFiles(torDirectory);
-					throw new PluginException();
-				}
-				//noinspection BusyWait
-				Thread.sleep(COOKIE_POLLING_INTERVAL_MS);
-			}
-			LOG.info("Auth cookie created");
+			tor.start();
 		} catch (InterruptedException e) {
 			LOG.warning("Interrupted while starting Tor");
 			Thread.currentThread().interrupt();
 			throw new PluginException();
-		}
-		try {
-			// Open a control connection and authenticate using the cookie file
-			controlSocket = new Socket("127.0.0.1", torControlPort);
-			controlConnection = new TorControlConnection(controlSocket);
-			controlConnection.authenticate(read(cookieFile));
-			// Tell Tor to exit when the control connection is closed
-			controlConnection.takeOwnership();
-			controlConnection.resetConf(singletonList(OWNER));
-			// Register to receive events from the Tor process
-			controlConnection.setEventHandler(this);
-			controlConnection.setEvents(asList(EVENTS));
-			// Check whether Tor has already bootstrapped
-			String info = controlConnection.getInfo("status/bootstrap-phase");
-			if (info != null && info.contains("PROGRESS=100")) {
-				LOG.info("Tor has already bootstrapped");
-				state.setBootstrapped();
-			}
-			// Check whether Tor has already built a circuit
-			info = controlConnection.getInfo("status/circuit-established");
-			if ("1".equals(info)) {
-				LOG.info("Tor has already built a circuit");
-				state.setCircuitBuilt(true);
-			}
 		} catch (IOException e) {
 			throw new PluginException(e);
 		}
-		state.setStarted();
 		// Check whether we're online
 		updateConnectionStatus(networkManager.getNetworkStatus(),
 				batteryManager.isCharging());
@@ -324,148 +210,6 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		bind();
 	}
 
-	private boolean assetsAreUpToDate() {
-		return doneFile.lastModified() > getLastUpdateTime();
-	}
-
-	private void installAssets() throws IOException {
-		// The done file may already exist from a previous installation
-		//noinspection ResultOfMethodCallIgnored
-		doneFile.delete();
-		// The GeoIP file may exist from a previous installation - we can
-		// save some space by deleting it.
-		// TODO: Remove after a reasonable migration period
-		//  (added 2022-03-29)
-		//noinspection ResultOfMethodCallIgnored
-		geoIpFile.delete();
-		installTorExecutable();
-		installObfs4Executable();
-		installSnowflakeExecutable();
-		if (!doneFile.createNewFile())
-			LOG.warning("Failed to create done file");
-	}
-
-	protected void extract(InputStream in, File dest) throws IOException {
-		OutputStream out = new FileOutputStream(dest);
-		copyAndClose(in, out);
-	}
-
-	protected void installTorExecutable() throws IOException {
-		if (LOG.isLoggable(INFO))
-			LOG.info("Installing Tor binary for " + architecture);
-		File torFile = getTorExecutableFile();
-		extract(getTorInputStream(), torFile);
-		if (!torFile.setExecutable(true, true)) throw new IOException();
-	}
-
-	protected void installObfs4Executable() throws IOException {
-		if (LOG.isLoggable(INFO))
-			LOG.info("Installing obfs4proxy binary for " + architecture);
-		File obfs4File = getObfs4ExecutableFile();
-		extract(getObfs4InputStream(), obfs4File);
-		if (!obfs4File.setExecutable(true, true)) throw new IOException();
-	}
-
-	protected void installSnowflakeExecutable() throws IOException {
-		if (LOG.isLoggable(INFO))
-			LOG.info("Installing snowflake binary for " + architecture);
-		File snowflakeFile = getSnowflakeExecutableFile();
-		extract(getSnowflakeInputStream(), snowflakeFile);
-		if (!snowflakeFile.setExecutable(true, true)) throw new IOException();
-	}
-
-	private InputStream getTorInputStream() throws IOException {
-		return getZipInputStream("tor");
-	}
-
-	private InputStream getObfs4InputStream() throws IOException {
-		return getZipInputStream("obfs4proxy");
-	}
-
-	private InputStream getSnowflakeInputStream() throws IOException {
-		return getZipInputStream("snowflake");
-	}
-
-	private InputStream getZipInputStream(String basename) throws IOException {
-		InputStream in = resourceProvider
-				.getResourceInputStream(basename + "_" + architecture, ".zip");
-		ZipInputStream zin = new ZipInputStream(in);
-		if (zin.getNextEntry() == null) throw new IOException();
-		return zin;
-	}
-
-	private static void append(StringBuilder strb, String name, Object value) {
-		strb.append(name);
-		strb.append(" ");
-		strb.append(value);
-		strb.append("\n");
-	}
-
-	private InputStream getConfigInputStream() {
-		File dataDirectory = new File(torDirectory, ".tor");
-		StringBuilder strb = new StringBuilder();
-		append(strb, "ControlPort", torControlPort);
-		append(strb, "CookieAuthentication", 1);
-		append(strb, "DataDirectory", dataDirectory.getAbsolutePath());
-		append(strb, "DisableNetwork", 1);
-		append(strb, "RunAsDaemon", 1);
-		append(strb, "SafeSocks", 1);
-		append(strb, "SocksPort", torSocksPort);
-		strb.append("GeoIPFile\n");
-		strb.append("GeoIPv6File\n");
-		append(strb, "ConnectionPadding", 0);
-		String obfs4Path = getObfs4ExecutableFile().getAbsolutePath();
-		append(strb, "ClientTransportPlugin obfs4 exec", obfs4Path);
-		append(strb, "ClientTransportPlugin meek_lite exec", obfs4Path);
-		String snowflakePath = getSnowflakeExecutableFile().getAbsolutePath();
-		append(strb, "ClientTransportPlugin snowflake exec", snowflakePath);
-		//noinspection CharsetObjectCanBeUsed
-		return new ByteArrayInputStream(
-				strb.toString().getBytes(Charset.forName("UTF-8")));
-	}
-
-	private void listFiles(File f) {
-		if (f.isDirectory()) {
-			File[] children = f.listFiles();
-			if (children != null) for (File child : children) listFiles(child);
-		} else {
-			LOG.info(f.getAbsolutePath() + " " + f.length());
-		}
-	}
-
-	private byte[] read(File f) throws IOException {
-		byte[] b = new byte[(int) f.length()];
-		FileInputStream in = new FileInputStream(f);
-		try {
-			int offset = 0;
-			while (offset < b.length) {
-				int read = in.read(b, offset, b.length - offset);
-				if (read == -1) throw new EOFException();
-				offset += read;
-			}
-			return b;
-		} finally {
-			tryToClose(in, LOG, WARNING);
-		}
-	}
-
-	protected void waitForTorToStart(Process torProcess)
-			throws InterruptedException, PluginException {
-		Scanner stdout = new Scanner(torProcess.getInputStream());
-		// Log the first line of stdout (contains Tor and library versions)
-		if (stdout.hasNextLine()) LOG.info(stdout.nextLine());
-		// Read the process's stdout (and redirected stderr) until it detaches
-		while (stdout.hasNextLine()) stdout.nextLine();
-		stdout.close();
-		// Wait for the process to detach or exit
-		int exit = torProcess.waitFor();
-		if (exit != 0) {
-			if (LOG.isLoggable(WARNING))
-				LOG.warning("Tor exited with value " + exit);
-			throw new PluginException();
-		}
-	}
-
 	private void bind() {
 		ioExecutor.execute(() -> {
 			// If there's already a port number stored in config, reuse it
@@ -489,9 +233,9 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 				return;
 			}
 			// Store the port number
-			String localPort = String.valueOf(ss.getLocalPort());
+			int localPort = ss.getLocalPort();
 			Settings s = new Settings();
-			s.put(PREF_TOR_PORT, localPort);
+			s.put(PREF_TOR_PORT, String.valueOf(localPort));
 			callback.mergeSettings(s);
 			// Create a hidden service if necessary
 			ioExecutor.execute(() -> publishHiddenService(localPort));
@@ -501,48 +245,28 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		});
 	}
 
-	private void publishHiddenService(String port) {
-		if (!state.isTorRunning()) return;
-		String privKey3 = settings.get(HS_PRIVATE_KEY_V3);
-		publishV3HiddenService(port, privKey3);
-	}
-
-	private void publishV3HiddenService(String port, @Nullable String privKey) {
+	private void publishHiddenService(int localPort) {
+		if (!tor.isTorRunning()) return;
+		String privKey = settings.get(HS_PRIVATE_KEY_V3);
 		LOG.info("Creating v3 hidden service");
-		Map<Integer, String> portLines = singletonMap(80, "127.0.0.1:" + port);
-		Map<String, String> response;
+		HiddenServiceProperties hsProps;
 		try {
-			// Use the control connection to set up the hidden service
-			if (privKey == null) {
-				response = controlConnection.addOnion("NEW:ED25519-V3",
-						portLines, null);
-			} else {
-				response = controlConnection.addOnion(privKey, portLines);
-			}
+			hsProps = tor.publishHiddenService(localPort, 80, privKey);
 		} catch (IOException e) {
 			logException(LOG, WARNING, e);
 			return;
 		}
-		if (!response.containsKey(HS_ADDRESS)) {
-			LOG.warning("Tor did not return a hidden service address");
-			return;
-		}
-		if (privKey == null && !response.containsKey(HS_PRIVKEY)) {
-			LOG.warning("Tor did not return a private key");
-			return;
-		}
-		String onion3 = response.get(HS_ADDRESS);
 		if (LOG.isLoggable(INFO)) {
-			LOG.info("V3 hidden service " + scrubOnion(onion3));
+			LOG.info("V3 hidden service " + scrubOnion(hsProps.onion));
 		}
 		if (privKey == null) {
 			// Publish the hidden service's onion hostname in transport props
 			TransportProperties p = new TransportProperties();
-			p.put(PROP_ONION_V3, onion3);
+			p.put(PROP_ONION_V3, hsProps.onion);
 			callback.mergeLocalProperties(p);
 			// Save the hidden service's private key for next time
 			Settings s = new Settings();
-			s.put(HS_PRIVATE_KEY_V3, response.get(HS_PRIVKEY));
+			s.put(HS_PRIVATE_KEY_V3, hsProps.privKey);
 			callback.mergeSettings(s);
 		}
 	}
@@ -565,50 +289,31 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		}
 	}
 
-	protected void enableNetwork(boolean enable) throws IOException {
-		if (!state.enableNetwork(enable)) return; // Unchanged
-		controlConnection.setConf("DisableNetwork", enable ? "0" : "1");
-	}
-
 	private void enableBridges(List<BridgeType> bridgeTypes, String countryCode)
 			throws IOException {
-		if (!state.setBridgeTypes(bridgeTypes)) return; // Unchanged
 		if (bridgeTypes.isEmpty()) {
-			controlConnection.setConf("UseBridges", "0");
-			controlConnection.resetConf(singletonList("Bridge"));
+			tor.disableBridges();
 		} else {
-			Collection<String> conf = new ArrayList<>();
-			conf.add("UseBridges 1");
-			boolean letsEncrypt = canVerifyLetsEncryptCerts();
+			List<String> bridges = new ArrayList<>();
 			for (BridgeType bridgeType : bridgeTypes) {
-				conf.addAll(circumventionProvider
-						.getBridges(bridgeType, countryCode, letsEncrypt));
+				bridges.addAll(circumventionProvider.getBridges(bridgeType,
+						countryCode, canVerifyLetsEncryptCerts));
 			}
-			controlConnection.setConf(conf);
+			tor.enableBridges(bridges);
 		}
 	}
 
-	/**
-	 * Returns true if this device can verify Let's Encrypt certificates signed
-	 * with the IdentTrust DST Root X3 certificate, which expired at the end of
-	 * September 2021.
-	 */
-	protected boolean canVerifyLetsEncryptCerts() {
-		return true;
-	}
-
 	@Override
 	public void stop() {
 		ServerSocket ss = state.setStopped();
 		tryToClose(ss, LOG, WARNING);
-		if (controlSocket != null && controlConnection != null) {
-			try {
-				LOG.info("Stopping Tor");
-				controlConnection.shutdownTor("TERM");
-				controlSocket.close();
-			} catch (IOException e) {
-				logException(LOG, WARNING, e);
-			}
+		try {
+			tor.stop();
+		} catch (IOException e) {
+			logException(LOG, WARNING, e);
+		} catch (InterruptedException e) {
+			LOG.warning("Interrupted while stopping Tor");
+			Thread.currentThread().interrupt();
 		}
 	}
 
@@ -719,6 +424,7 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		TransportProperties remoteProperties = new TransportProperties();
 		remoteProperties.put(PROP_ONION_V3, remoteOnion);
 		try {
+			@SuppressWarnings("resource")
 			ServerSocket ss = new ServerSocket();
 			ss.bind(new InetSocketAddress("127.0.0.1", 0));
 			int port = ss.getLocalPort();
@@ -735,9 +441,7 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 					LOG.info("Rendezvous server socket closed");
 				}
 			});
-			Map<Integer, String> portLines =
-					singletonMap(80, "127.0.0.1:" + port);
-			controlConnection.addOnion(blob, portLines);
+			tor.publishHiddenService(port, 80, blob);
 			return new RendezvousEndpoint() {
 
 				@Override
@@ -747,8 +451,11 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 
 				@Override
 				public void close() throws IOException {
-					controlConnection.delOnion(localOnion);
-					tryToClose(ss, LOG, WARNING);
+					try {
+						tor.removeHiddenService(localOnion);
+					} finally {
+						tryToClose(ss, LOG, WARNING);
+					}
 				}
 			};
 		} catch (IOException e) {
@@ -757,121 +464,6 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		}
 	}
 
-	@Override
-	public void circuitStatus(String status, String id, String path) {
-		// In case of races between receiving CIRCUIT_ESTABLISHED and setting
-		// DisableNetwork, set our circuitBuilt flag if not already set
-		if (status.equals("BUILT") && state.setCircuitBuilt(true)) {
-			LOG.info("Circuit built");
-			backoff.reset();
-		}
-	}
-
-	@Override
-	public void streamStatus(String status, String id, String target) {
-	}
-
-	@Override
-	public void orConnStatus(String status, String orName) {
-		if (LOG.isLoggable(INFO)) LOG.info("OR connection " + status);
-
-		if (status.equals("CONNECTED")) state.onOrConnectionConnected();
-		else if (status.equals("CLOSED")) state.onOrConnectionClosed();
-	}
-
-	@Override
-	public void bandwidthUsed(long read, long written) {
-	}
-
-	@Override
-	public void newDescriptors(List<String> orList) {
-	}
-
-	@Override
-	public void message(String severity, String msg) {
-		if (LOG.isLoggable(INFO)) LOG.info(severity + " " + msg);
-	}
-
-	@Override
-	public void unrecognized(String type, String msg) {
-		if (type.equals("STATUS_CLIENT")) {
-			handleClientStatus(removeSeverity(msg));
-		} else if (type.equals("STATUS_GENERAL")) {
-			handleGeneralStatus(removeSeverity(msg));
-		} else if (type.equals("HS_DESC") && msg.startsWith("UPLOADED")) {
-			String[] parts = msg.split(" ");
-			if (parts.length < 2) {
-				LOG.warning("Failed to parse HS_DESC UPLOADED event");
-			} else if (LOG.isLoggable(INFO)) {
-				LOG.info("V3 descriptor uploaded for " + scrubOnion(parts[1]));
-			}
-		}
-	}
-
-	@Override
-	public void controlConnectionClosed() {
-		if (state.isTorRunning()) {
-			// TODO: Restart the Tor process
-			LOG.warning("Control connection closed");
-		}
-	}
-
-	private String removeSeverity(String msg) {
-		return msg.replaceFirst("[^ ]+ ", "");
-	}
-
-	private void handleClientStatus(String msg) {
-		if (msg.startsWith("BOOTSTRAP PROGRESS=100")) {
-			LOG.info("Bootstrapped");
-			state.setBootstrapped();
-			backoff.reset();
-		} else if (msg.startsWith("CIRCUIT_ESTABLISHED")) {
-			if (state.setCircuitBuilt(true)) {
-				LOG.info("Circuit built");
-				backoff.reset();
-			}
-		} else if (msg.startsWith("CIRCUIT_NOT_ESTABLISHED")) {
-			if (state.setCircuitBuilt(false)) {
-				LOG.info("Circuit not built");
-				// TODO: Disable and re-enable network to prompt Tor to rebuild
-				//  its guard/bridge connections? This will also close any
-				//  established circuits, which might still be functioning
-			}
-		}
-	}
-
-	private void handleGeneralStatus(String msg) {
-		if (msg.startsWith("CLOCK_JUMPED")) {
-			Long time = parseLongArgument(msg, "TIME");
-			if (time != null && LOG.isLoggable(WARNING)) {
-				LOG.warning("Clock jumped " + time + " seconds");
-			}
-		} else if (msg.startsWith("CLOCK_SKEW")) {
-			Long skew = parseLongArgument(msg, "SKEW");
-			if (skew != null && LOG.isLoggable(WARNING)) {
-				LOG.warning("Clock is skewed by " + skew + " seconds");
-			}
-		}
-	}
-
-	@Nullable
-	private Long parseLongArgument(String msg, String argName) {
-		String[] args = msg.split(" ");
-		for (String arg : args) {
-			if (arg.startsWith(argName + "=")) {
-				try {
-					return Long.parseLong(arg.substring(argName.length() + 1));
-				} catch (NumberFormatException e) {
-					break;
-				}
-			}
-		}
-		if (LOG.isLoggable(WARNING)) {
-			LOG.warning("Failed to parse " + argName + " from '" + msg + "'");
-		}
-		return null;
-	}
-
 	@Override
 	public void eventOccurred(Event e) {
 		if (e instanceof SettingsUpdatedEvent) {
@@ -894,7 +486,7 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	private void updateConnectionStatus(NetworkStatus status,
 			boolean charging) {
 		connectionStatusExecutor.execute(() -> {
-			if (!state.isTorRunning()) return;
+			if (!tor.isTorRunning()) return;
 			boolean online = status.isConnected();
 			boolean wifi = status.isWifi();
 			boolean ipv6Only = status.isIpv6Only();
@@ -978,41 +570,22 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 			try {
 				if (enableNetwork) {
 					enableBridges(bridgeTypes, country);
-					enableConnectionPadding(enableConnectionPadding);
-					enableIpv6(ipv6Only);
+					tor.enableConnectionPadding(enableConnectionPadding);
+					tor.enableIpv6(ipv6Only);
 				}
-				enableNetwork(enableNetwork);
+				tor.enableNetwork(enableNetwork);
 			} catch (IOException e) {
 				logException(LOG, WARNING, e);
 			}
 		});
 	}
 
-	private void enableConnectionPadding(boolean enable) throws IOException {
-		if (!state.enableConnectionPadding(enable)) return; // Unchanged
-		controlConnection.setConf("ConnectionPadding", enable ? "1" : "0");
-	}
-
-	private void enableIpv6(boolean enable) throws IOException {
-		if (!state.enableIpv6(enable)) return; // Unchanged
-		controlConnection.setConf("ClientUseIPv4", enable ? "0" : "1");
-		controlConnection.setConf("ClientUseIPv6", enable ? "1" : "0");
-	}
-
 	@ThreadSafe
 	@NotNullByDefault
-	protected class PluginState {
+	private class PluginState {
 
 		@GuardedBy("this")
-		private boolean started = false,
-				stopped = false,
-				networkInitialised = false,
-				networkEnabled = false,
-				paddingEnabled = false,
-				ipv6Enabled = false,
-				bootstrapped = false,
-				circuitBuilt = false,
-				settingsChecked = false;
+		private boolean settingsChecked = false;
 
 		@GuardedBy("this")
 		private int reasonsDisabled = 0;
@@ -1021,84 +594,13 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		@Nullable
 		private ServerSocket serverSocket = null;
 
-		@GuardedBy("this")
-		private int orConnectionsConnected = 0;
-
-		@GuardedBy("this")
-		private List<BridgeType> bridgeTypes = emptyList();
-
-		private synchronized void setStarted() {
-			started = true;
-			callback.pluginStateChanged(getState());
-		}
-
-		@SuppressWarnings("BooleanMethodIsAlwaysInverted")
-		private synchronized boolean isTorRunning() {
-			return started && !stopped;
-		}
-
 		@Nullable
 		private synchronized ServerSocket setStopped() {
-			stopped = true;
 			ServerSocket ss = serverSocket;
 			serverSocket = null;
-			callback.pluginStateChanged(getState());
 			return ss;
 		}
 
-		private synchronized void setBootstrapped() {
-			boolean wasBootstrapped = bootstrapped;
-			bootstrapped = true;
-			if (!wasBootstrapped) callback.pluginStateChanged(getState());
-		}
-
-		/**
-		 * Sets the `circuitBuilt` flag and returns true if the flag has
-		 * changed.
-		 */
-		private synchronized boolean setCircuitBuilt(boolean built) {
-			if (built == circuitBuilt) return false; // Unchanged
-			circuitBuilt = built;
-			callback.pluginStateChanged(getState());
-			return true; // Changed
-		}
-
-		/**
-		 * Sets the `networkEnabled` flag and returns true if the flag has
-		 * changed.
-		 */
-		private synchronized boolean enableNetwork(boolean enable) {
-			boolean wasInitialised = networkInitialised;
-			boolean wasEnabled = networkEnabled;
-			networkInitialised = true;
-			networkEnabled = enable;
-			if (!enable) circuitBuilt = false;
-			if (!wasInitialised || enable != wasEnabled) {
-				callback.pluginStateChanged(getState());
-			}
-			return enable != wasEnabled;
-		}
-
-		/**
-		 * Sets the `paddingEnabled` flag and returns true if the flag has
-		 * changed. Doesn't affect getState().
-		 */
-		private synchronized boolean enableConnectionPadding(boolean enable) {
-			if (enable == paddingEnabled) return false; // Unchanged
-			paddingEnabled = enable;
-			return true; // Changed
-		}
-
-		/**
-		 * Sets the `ipv6Enabled` flag and returns true if the flag has
-		 * changed. Doesn't affect getState().
-		 */
-		private synchronized boolean enableIpv6(boolean enable) {
-			if (enable == ipv6Enabled) return false; // Unchanged
-			ipv6Enabled = enable;
-			return true; // Changed
-		}
-
 		private synchronized void setReasonsDisabled(int reasons) {
 			boolean wasChecked = settingsChecked;
 			settingsChecked = true;
@@ -1111,7 +613,7 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 
 		// Doesn't affect getState()
 		private synchronized boolean setServerSocket(ServerSocket ss) {
-			if (stopped || serverSocket != null) return false;
+			if (serverSocket != null || !tor.isTorRunning()) return false;
 			serverSocket = ss;
 			return true;
 		}
@@ -1121,57 +623,33 @@ abstract class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 			if (serverSocket == ss) serverSocket = null;
 		}
 
-		/**
-		 * Sets the list of bridge types being used and returns true if the
-		 * list has changed. The list is empty if bridges are disabled.
-		 * Doesn't affect getState().
-		 */
-		private synchronized boolean setBridgeTypes(List<BridgeType> types) {
-			if (types.equals(bridgeTypes)) return false; // Unchanged
-			bridgeTypes = types;
-			return true; // Changed
+		private synchronized State getState() {
+			return getState(tor.getTorState());
 		}
 
-		private synchronized State getState() {
-			if (!started || stopped || !settingsChecked) {
+		private synchronized State getState(TorState torState) {
+			// Treat TorState.STARTED as State.STARTING_STOPPING because it's
+			// only seen during startup, before TorWrapper#enableNetwork() is
+			// called for the first time. TorState.NOT_STARTED and
+			// TorState.STOPPED are mapped to State.STARTING_STOPPING because
+			// that's the State before we've started and after we've stopped.
+			if (torState == TorState.NOT_STARTED ||
+					torState == TorState.STARTING ||
+					torState == TorState.STARTED ||
+					torState == TorState.STOPPING ||
+					torState == TorState.STOPPED ||
+					!settingsChecked) {
 				return STARTING_STOPPING;
 			}
 			if (reasonsDisabled != 0) return DISABLED;
-			if (!networkInitialised) return ENABLING;
-			if (!networkEnabled) return INACTIVE;
-			return bootstrapped && circuitBuilt && orConnectionsConnected > 0
-					? ACTIVE : ENABLING;
+			if (torState == TorState.CONNECTING) return ENABLING;
+			if (torState == TorState.CONNECTED) return ACTIVE;
+			// The plugin is enabled in settings but the device is offline
+			return INACTIVE;
 		}
 
 		private synchronized int getReasonsDisabled() {
 			return getState() == DISABLED ? reasonsDisabled : 0;
 		}
-
-		private synchronized void onOrConnectionConnected() {
-			int oldConnected = orConnectionsConnected;
-			orConnectionsConnected++;
-			logOrConnections();
-			if (oldConnected == 0) callback.pluginStateChanged(getState());
-		}
-
-		private synchronized void onOrConnectionClosed() {
-			int oldConnected = orConnectionsConnected;
-			orConnectionsConnected--;
-			if (orConnectionsConnected < 0) {
-				LOG.warning("Count was zero before connection closed");
-				orConnectionsConnected = 0;
-			}
-			logOrConnections();
-			if (orConnectionsConnected == 0 && oldConnected != 0) {
-				callback.pluginStateChanged(getState());
-			}
-		}
-
-		@GuardedBy("this")
-		private void logOrConnections() {
-			if (LOG.isLoggable(INFO)) {
-				LOG.info(orConnectionsConnected + " OR connections connected");
-			}
-		}
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/TorPluginFactory.java

@@ -3,6 +3,7 @@ package org.briarproject.bramble.plugin.tor;
 import org.briarproject.bramble.api.battery.BatteryManager;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.event.EventExecutor;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.network.NetworkManager;
 import org.briarproject.bramble.api.plugin.Backoff;
@@ -16,10 +17,10 @@ import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
 import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.api.system.ResourceProvider;
 import org.briarproject.bramble.api.system.WakefulIoExecutor;
 import org.briarproject.nullsafety.NotNullByDefault;
+import org.briarproject.onionwrapper.CircumventionProvider;
+import org.briarproject.onionwrapper.LocationUtils;
 
 import java.io.File;
 import java.util.concurrent.Executor;
@@ -45,13 +46,12 @@ abstract class TorPluginFactory implements DuplexPluginFactory {
 	private static final int MAX_POLLING_INTERVAL = 10 * 60 * 1000; // 10 mins
 	private static final double BACKOFF_BASE = 1.2;
 
-	protected final Executor ioExecutor, wakefulIoExecutor;
+	protected final Executor ioExecutor, eventExecutor, wakefulIoExecutor;
 	protected final NetworkManager networkManager;
 	protected final LocationUtils locationUtils;
 	protected final EventBus eventBus;
 	protected final SocketFactory torSocketFactory;
 	protected final BackoffFactory backoffFactory;
-	protected final ResourceProvider resourceProvider;
 	protected final CircumventionProvider circumventionProvider;
 	protected final BatteryManager batteryManager;
 	protected final Clock clock;
@@ -61,13 +61,13 @@ abstract class TorPluginFactory implements DuplexPluginFactory {
 	protected final int torControlPort;
 
 	TorPluginFactory(@IoExecutor Executor ioExecutor,
+			@EventExecutor Executor eventExecutor,
 			@WakefulIoExecutor Executor wakefulIoExecutor,
 			NetworkManager networkManager,
 			LocationUtils locationUtils,
 			EventBus eventBus,
 			SocketFactory torSocketFactory,
 			BackoffFactory backoffFactory,
-			ResourceProvider resourceProvider,
 			CircumventionProvider circumventionProvider,
 			BatteryManager batteryManager,
 			Clock clock,
@@ -76,13 +76,13 @@ abstract class TorPluginFactory implements DuplexPluginFactory {
 			@TorSocksPort int torSocksPort,
 			@TorControlPort int torControlPort) {
 		this.ioExecutor = ioExecutor;
+		this.eventExecutor = eventExecutor;
 		this.wakefulIoExecutor = wakefulIoExecutor;
 		this.networkManager = networkManager;
 		this.locationUtils = locationUtils;
 		this.eventBus = eventBus;
 		this.torSocketFactory = torSocketFactory;
 		this.backoffFactory = backoffFactory;
-		this.resourceProvider = resourceProvider;
 		this.circumventionProvider = circumventionProvider;
 		this.batteryManager = batteryManager;
 		this.clock = clock;

bramble-core/src/main/java/org/briarproject/bramble/plugin/tor/TorRendezvousCryptoImpl.java

@@ -7,7 +7,7 @@ import net.i2p.crypto.eddsa.spec.EdDSAPrivateKeySpec;
 import org.bouncycastle.util.encoders.Base64;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 
-import java.nio.charset.Charset;
+import static org.briarproject.bramble.util.StringUtils.US_ASCII;
 
 class TorRendezvousCryptoImpl implements TorRendezvousCrypto {
 
@@ -31,6 +31,6 @@ class TorRendezvousCryptoImpl implements TorRendezvousCrypto {
 		EdDSAPrivateKeySpec spec = new EdDSAPrivateKeySpec(seed, CURVE_SPEC);
 		byte[] hash = spec.getH();
 		byte[] base64 = Base64.encode(hash);
-		return "ED25519-V3:" + new String(base64, Charset.forName("US-ASCII"));
+		return "ED25519-V3:" + new String(base64, US_ASCII);
 	}
 }

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

@@ -201,7 +201,7 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 			// Retrieve and parse the latest local properties
 			for (Entry<TransportId, LatestUpdate> e : latest.entrySet()) {
 				BdfList message = clientHelper.getMessageAsList(txn,
-						e.getValue().messageId);
+						e.getValue().messageId, false);
 				local.put(e.getKey(), parseProperties(message));
 			}
 			return local;
@@ -222,7 +222,7 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				if (latest != null) {
 					// Retrieve and parse the latest local properties
 					BdfList message = clientHelper.getMessageAsList(txn,
-							latest.messageId);
+							latest.messageId, false);
 					p = parseProperties(message);
 				}
 				return p == null ? new TransportProperties() : p;
@@ -252,7 +252,7 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				local = new TransportProperties();
 			} else {
 				BdfList message = clientHelper.getMessageAsList(txn,
-						latest.messageId);
+						latest.messageId, false);
 				local = parseProperties(message);
 			}
 			storeLocalProperties(txn, c, t, local);
@@ -272,8 +272,8 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				remote = new TransportProperties();
 			} else {
 				// Retrieve and parse the latest remote properties
-				BdfList message =
-						clientHelper.getMessageAsList(txn, latest.messageId);
+				BdfList message = clientHelper.getMessageAsList(txn,
+						latest.messageId, false);
 				remote = parseProperties(message);
 			}
 			// Merge in any discovered properties
@@ -311,13 +311,14 @@ class TransportPropertyManagerImpl implements TransportPropertyManager,
 				if (latest == null) {
 					merged = new TransportProperties(p);
 					Iterator<String> it = merged.values().iterator();
+					//noinspection Java8CollectionRemoveIf
 					while (it.hasNext()) {
 						if (isNullOrEmpty(it.next())) it.remove();
 					}
 					changed = true;
 				} else {
 					BdfList message = clientHelper.getMessageAsList(txn,
-							latest.messageId);
+							latest.messageId, false);
 					TransportProperties old = parseProperties(message);
 					merged = new TransportProperties(old);
 					for (Entry<String, String> e : p.entrySet()) {

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

@@ -27,7 +27,10 @@ class TransportPropertyValidator extends BdfMessageValidator {
 
 	TransportPropertyValidator(ClientHelper clientHelper,
 			MetadataEncoder metadataEncoder, Clock clock) {
-		super(clientHelper, metadataEncoder, clock);
+		// Accept transport properties in non-canonical form
+		// TODO: Remove this after a reasonable migration period
+		//  (added 2023-02-17)
+		super(clientHelper, metadataEncoder, clock, false);
 	}
 
 	@Override

bramble-core/src/main/java/org/briarproject/bramble/qrcode/QrCodeClassifierImpl.java

@@ -0,0 +1,42 @@
+package org.briarproject.bramble.qrcode;
+
+import org.briarproject.bramble.api.Pair;
+import org.briarproject.bramble.api.keyagreement.KeyAgreementConstants;
+import org.briarproject.bramble.api.mailbox.MailboxConstants;
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier;
+import org.briarproject.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+import javax.inject.Inject;
+
+import static org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType.BQP;
+import static org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType.MAILBOX;
+import static org.briarproject.bramble.api.qrcode.QrCodeClassifier.QrCodeType.UNKNOWN;
+import static org.briarproject.bramble.util.StringUtils.ISO_8859_1;
+
+@Immutable
+@NotNullByDefault
+class QrCodeClassifierImpl implements QrCodeClassifier {
+
+	@Inject
+	QrCodeClassifierImpl() {
+	}
+
+	@Override
+	public Pair<QrCodeType, Integer> classifyQrCode(String payload) {
+		byte[] bytes = payload.getBytes(ISO_8859_1);
+		if (bytes.length == 0) return new Pair<>(UNKNOWN, 0);
+		// If this is a Bramble QR code then the first byte encodes the
+		// format ID (3 bits) and version (5 bits)
+		int formatIdAndVersion = bytes[0] & 0xFF;
+		int formatId = formatIdAndVersion >> 5;
+		int formatVersion = formatIdAndVersion & 0x1F;
+		if (formatId == KeyAgreementConstants.QR_FORMAT_ID) {
+			return new Pair<>(BQP, formatVersion);
+		}
+		if (formatId == MailboxConstants.QR_FORMAT_ID) {
+			return new Pair<>(MAILBOX, formatVersion);
+		}
+		return new Pair<>(UNKNOWN, 0);
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/qrcode/QrCodeModule.java

@@ -0,0 +1,16 @@
+package org.briarproject.bramble.qrcode;
+
+import org.briarproject.bramble.api.qrcode.QrCodeClassifier;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class QrCodeModule {
+
+	@Provides
+	QrCodeClassifier provideQrCodeClassifier(
+			QrCodeClassifierImpl qrCodeClassifier) {
+		return qrCodeClassifier;
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/record/RecordReaderImpl.java

@@ -1,7 +1,6 @@
 package org.briarproject.bramble.record;
 
 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.Predicate;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
 import org.briarproject.bramble.util.ByteUtils;
@@ -45,7 +44,7 @@ class RecordReaderImpl implements RecordReader {
 
 	@Nullable
 	@Override
-	public Record readRecord(Predicate<Record> accept, Predicate<Record> ignore)
+	public Record readRecord(RecordPredicate accept, RecordPredicate ignore)
 			throws IOException {
 		while (true) {
 			if (eof()) return null;

bramble-core/src/main/java/org/briarproject/bramble/sync/SyncRecordReaderImpl.java

@@ -1,10 +1,10 @@
 package org.briarproject.bramble.sync;
 
 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.Predicate;
 import org.briarproject.bramble.api.UniqueId;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
+import org.briarproject.bramble.api.record.RecordReader.RecordPredicate;
 import org.briarproject.bramble.api.sync.Ack;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageFactory;
@@ -30,6 +30,7 @@ import static org.briarproject.bramble.api.sync.RecordTypes.OFFER;
 import static org.briarproject.bramble.api.sync.RecordTypes.PRIORITY;
 import static org.briarproject.bramble.api.sync.RecordTypes.REQUEST;
 import static org.briarproject.bramble.api.sync.RecordTypes.VERSIONS;
+import static org.briarproject.bramble.api.sync.SyncConstants.MAX_MESSAGE_LENGTH;
 import static org.briarproject.bramble.api.sync.SyncConstants.MAX_SUPPORTED_VERSIONS;
 import static org.briarproject.bramble.api.sync.SyncConstants.MESSAGE_HEADER_LENGTH;
 import static org.briarproject.bramble.api.sync.SyncConstants.PRIORITY_NONCE_BYTES;
@@ -40,12 +41,12 @@ import static org.briarproject.bramble.api.sync.SyncConstants.PROTOCOL_VERSION;
 class SyncRecordReaderImpl implements SyncRecordReader {
 
 	// Accept records with current protocol version, known record type
-	private static final Predicate<Record> ACCEPT = r ->
+	private static final RecordPredicate ACCEPT = r ->
 			r.getProtocolVersion() == PROTOCOL_VERSION &&
 					isKnownRecordType(r.getRecordType());
 
 	// Ignore records with current protocol version, unknown record type
-	private static final Predicate<Record> IGNORE = r ->
+	private static final RecordPredicate IGNORE = r ->
 			r.getProtocolVersion() == PROTOCOL_VERSION &&
 					!isKnownRecordType(r.getRecordType());
 
@@ -126,6 +127,8 @@ class SyncRecordReaderImpl implements SyncRecordReader {
 		byte[] payload = nextRecord.getPayload();
 		if (payload.length <= MESSAGE_HEADER_LENGTH)
 			throw new FormatException();
+		if (payload.length > MAX_MESSAGE_LENGTH)
+			throw new FormatException();
 		// Validate timestamp
 		long timestamp = ByteUtils.readUint64(payload, UniqueId.LENGTH);
 		if (timestamp < 0) throw new FormatException();

bramble-core/src/main/java/org/briarproject/bramble/transport/agreement/SessionParserImpl.java

@@ -32,8 +32,7 @@ class SessionParserImpl implements SessionParser {
 
 	@Override
 	public Session parseSession(BdfDictionary meta) throws FormatException {
-		State state =
-				State.fromValue(meta.getLong(SESSION_KEY_STATE).intValue());
+		State state = State.fromValue(meta.getInt(SESSION_KEY_STATE));
 
 		MessageId lastLocalMessageId = null;
 		byte[] lastLocalMessageIdBytes =
@@ -56,9 +55,9 @@ class SessionParserImpl implements SessionParser {
 		Long localTimestamp = meta.getOptionalLong(SESSION_KEY_LOCAL_TIMESTAMP);
 
 		KeySetId keySetId = null;
-		Long keySetIdLong = meta.getOptionalLong(SESSION_KEY_KEY_SET_ID);
-		if (keySetIdLong != null) {
-			keySetId = new KeySetId(keySetIdLong.intValue());
+		Integer keySetIdInt = meta.getOptionalInt(SESSION_KEY_KEY_SET_ID);
+		if (keySetIdInt != null) {
+			keySetId = new KeySetId(keySetIdInt);
 		}
 
 		return new Session(state, lastLocalMessageId, localKeyPair,

bramble-core/src/main/java/org/briarproject/bramble/transport/agreement/TransportKeyAgreementManagerImpl.java

@@ -177,8 +177,8 @@ class TransportKeyAgreementManagerImpl extends BdfIncomingMessageHook
 	protected DeliveryAction incomingMessage(Transaction txn, Message m,
 			BdfList body, BdfDictionary meta)
 			throws DbException, FormatException {
-		MessageType type = MessageType.fromValue(
-				meta.getLong(MSG_KEY_MESSAGE_TYPE).intValue());
+		MessageType type =
+				MessageType.fromValue(meta.getInt(MSG_KEY_MESSAGE_TYPE));
 		TransportId t = new TransportId(meta.getString(MSG_KEY_TRANSPORT_ID));
 		if (LOG.isLoggable(INFO)) {
 			LOG.info("Received " + type + " message for " + t);

bramble-core/src/main/java/org/briarproject/bramble/transport/agreement/TransportKeyAgreementValidator.java

@@ -42,7 +42,7 @@ class TransportKeyAgreementValidator extends BdfMessageValidator {
 	@Override
 	protected BdfMessageContext validateMessage(Message m, Group g,
 			BdfList body) throws FormatException {
-		MessageType type = MessageType.fromValue(body.getLong(0).intValue());
+		MessageType type = MessageType.fromValue(body.getInt(0));
 		if (type == KEY) return validateKeyMessage(m.getTimestamp(), body);
 		else if (type == ACTIVATE) return validateActivateMessage(body);
 		else throw new AssertionError();

bramble-core/src/main/java/org/briarproject/bramble/versioning/ClientVersioningManagerImpl.java

@@ -301,8 +301,8 @@ class ClientVersioningManagerImpl implements ClientVersioningManager,
 		for (int i = 0; i < size; i++) {
 			BdfList cv = body.getList(i);
 			ClientId clientId = new ClientId(cv.getString(0));
-			int majorVersion = cv.getLong(1).intValue();
-			int minorVersion = cv.getLong(2).intValue();
+			int majorVersion = cv.getInt(1);
+			int minorVersion = cv.getInt(2);
 			parsed.add(new ClientVersion(clientId, majorVersion, minorVersion));
 		}
 		return parsed;
@@ -408,8 +408,8 @@ class ClientVersioningManagerImpl implements ClientVersioningManager,
 			throws FormatException {
 		// Client ID, major version, minor version, active
 		ClientId clientId = new ClientId(clientState.getString(0));
-		int majorVersion = clientState.getLong(1).intValue();
-		int minorVersion = clientState.getLong(2).intValue();
+		int majorVersion = clientState.getInt(1);
+		int minorVersion = clientState.getInt(2);
 		boolean active = clientState.getBoolean(3);
 		return new ClientState(clientId, majorVersion, minorVersion, active);
 	}