Add an absurd amount of logging.

Don't try to get item at NO_POSITION

Closes #1517

See merge request briar/briar!1068

.idea/codeStyles/Project.xml

@@ -36,6 +36,9 @@
       <option name="JD_ALIGN_PARAM_COMMENTS" value="false" />
       <option name="JD_ALIGN_EXCEPTION_COMMENTS" value="false" />
     </JavaCodeStyleSettings>
+    <JetCodeStyleSettings>
+      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
+    </JetCodeStyleSettings>
     <Objective-C-extensions>
       <file>
         <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Import" />
@@ -257,5 +260,11 @@
         </rules>
       </arrangement>
     </codeStyleSettings>
+    <codeStyleSettings language="kotlin">
+      <option name="CODE_STYLE_DEFAULTS" value="KOTLIN_OFFICIAL" />
+      <option name="PARAMETER_ANNOTATION_WRAP" value="1" />
+      <option name="VARIABLE_ANNOTATION_WRAP" value="1" />
+      <option name="ENUM_CONSTANTS_WRAP" value="1" />
+    </codeStyleSettings>
   </code_scheme>
 </component>

.idea/runConfigurations/All_in_briar_headless.xml

@@ -0,0 +1,20 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="All in briar-headless" type="AndroidJUnit" factoryName="Android JUnit" nameIsGenerated="true">
+    <module name="briar-headless" />
+    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
+    <option name="ALTERNATIVE_JRE_PATH" />
+    <option name="PACKAGE_NAME" value="org.briarproject.briar.headless" />
+    <option name="MAIN_CLASS_NAME" value="" />
+    <option name="METHOD_NAME" value="" />
+    <option name="TEST_OBJECT" value="package" />
+    <option name="VM_PARAMETERS" value="" />
+    <option name="PARAMETERS" value="" />
+    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-headless" />
+    <option name="PASS_PARENT_ENVS" value="true" />
+    <option name="TEST_SEARCH_SCOPE">
+      <value defaultName="singleModule" />
+    </option>
+    <patterns />
+    <method />
+  </configuration>
+</component>

.idea/runConfigurations/All_tests.xml

@@ -24,6 +24,7 @@
       <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-android" run_configuration_type="AndroidJUnit" />
       <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-java" run_configuration_type="AndroidJUnit" />
       <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in briar-core" run_configuration_type="AndroidJUnit" />
+      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All in briar-headless" run_configuration_type="AndroidJUnit" />
     </method>
   </configuration>
-</component>
+</component>

.idea/runConfigurations/All_tests_in_bramble_android.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="All tests in bramble-android" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="bramble-android" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-android" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/All_tests_in_bramble_api.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="All tests in bramble-api" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="bramble-api" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-api" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/All_tests_in_bramble_core.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="All tests in bramble-core" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="bramble-core" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-core" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/All_tests_in_bramble_java.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="All tests in bramble-java" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="bramble-java" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea -Djava.library.path=libs" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-java" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/All_tests_in_briar_android.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="All tests in briar-android" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="briar-android" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-android" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/All_tests_in_briar_core.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="All tests in briar-core" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="briar-core" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-core" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/H2_Performance_Test.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="H2 Performance Test" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="bramble-core" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/HyperSQL_Performance_Test.xml

@@ -1,6 +1,5 @@
 <component name="ProjectRunConfigurationManager">
   <configuration default="false" name="HyperSQL Performance Test" type="AndroidJUnit" factoryName="Android JUnit">
-    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
     <module name="bramble-core" />
     <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
     <option name="ALTERNATIVE_JRE_PATH" />
@@ -11,12 +10,10 @@
     <option name="VM_PARAMETERS" value="-ea" />
     <option name="PARAMETERS" value="" />
     <option name="WORKING_DIRECTORY" value="" />
-    <option name="ENV_VARIABLES" />
     <option name="PASS_PARENT_ENVS" value="true" />
     <option name="TEST_SEARCH_SCOPE">
       <value defaultName="singleModule" />
     </option>
-    <envs />
     <patterns />
     <method />
   </configuration>

.idea/runConfigurations/briar_headless.xml

@@ -0,0 +1,17 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="briar-headless" type="JetRunConfigurationType" factoryName="Kotlin" singleton="true">
+    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
+    <option name="VM_PARAMETERS" value="" />
+    <option name="PROGRAM_PARAMETERS" value="-v" />
+    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
+    <option name="ALTERNATIVE_JRE_PATH" />
+    <option name="PASS_PARENT_ENVS" value="true" />
+    <option name="MAIN_CLASS_NAME" value="org.briarproject.briar.headless.MainKt" />
+    <option name="WORKING_DIRECTORY" value="" />
+    <module name="briar-headless" />
+    <envs />
+    <method>
+      <option name="Gradle.BeforeRunTask" enabled="true" tasks="jar" externalProjectPath="$PROJECT_DIR$/briar-headless" vmOptions="" scriptParameters="" />
+    </method>
+  </configuration>
+</component>

bramble-android/build.gradle

@@ -1,16 +1,18 @@
+import com.android.build.gradle.tasks.MergeResources
+
 apply plugin: 'com.android.library'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
 
 android {
-	compileSdkVersion 27
-	buildToolsVersion '27.0.3'
+	compileSdkVersion 28
+	buildToolsVersion '28.0.3'
 
 	defaultConfig {
 		minSdkVersion 14
 		targetSdkVersion 26
-		versionCode 10101
-		versionName "1.1.1"
+		versionCode 10106
+		versionName "1.1.6"
 		consumerProguardFiles 'proguard-rules.txt'
 
 		testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
@@ -28,9 +30,10 @@ configurations {
 
 dependencies {
 	implementation project(path: ':bramble-core', configuration: 'default')
-	tor 'org.briarproject:tor-android:0.2.9.16@zip'
+	tor 'org.briarproject:tor-android:0.3.5.8@zip'
+	tor 'org.briarproject:obfs4proxy-android:0.0.9@zip'
 
-	annotationProcessor 'com.google.dagger:dagger-compiler:2.0.2'
+	annotationProcessor 'com.google.dagger:dagger-compiler:2.19'
 
 	compileOnly 'javax.annotation:jsr250-api:1.0'
 
@@ -39,13 +42,29 @@ dependencies {
 	testImplementation "org.jmock:jmock:2.8.2"
 	testImplementation "org.jmock:jmock-junit4:2.8.2"
 	testImplementation "org.jmock:jmock-legacy:2.8.2"
-	testImplementation "org.hamcrest:hamcrest-library:1.3"
-	testImplementation "org.hamcrest:hamcrest-core:1.3"
 }
 
-project.afterEvaluate {
-	copy {
-		from configurations.tor.collect { zipTree(it) }
-		into 'src/main/res/raw'
+def torBinariesDir = 'src/main/res/raw'
+
+task cleanTorBinaries {
+	doLast {
+		delete fileTree(torBinariesDir) { include '*.zip' }
 	}
 }
+
+clean.dependsOn cleanTorBinaries
+
+task unpackTorBinaries {
+	doLast {
+		copy {
+			from configurations.tor.collect { zipTree(it) }
+			into torBinariesDir
+		}
+	}
+	dependsOn cleanTorBinaries
+}
+
+tasks.withType(MergeResources) {
+	inputs.dir torBinariesDir
+	dependsOn unpackTorBinaries
+}

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

@@ -0,0 +1,11 @@
+package org.briarproject.bramble;
+
+import org.briarproject.bramble.battery.AndroidBatteryModule;
+import org.briarproject.bramble.network.AndroidNetworkModule;
+
+public interface BrambleAndroidEagerSingletons {
+
+	void inject(AndroidBatteryModule.EagerSingletons init);
+
+	void inject(AndroidNetworkModule.EagerSingletons init);
+}

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

@@ -1,5 +1,6 @@
 package org.briarproject.bramble;
 
+import org.briarproject.bramble.battery.AndroidBatteryModule;
 import org.briarproject.bramble.network.AndroidNetworkModule;
 import org.briarproject.bramble.plugin.tor.CircumventionModule;
 import org.briarproject.bramble.system.AndroidSystemModule;
@@ -7,10 +8,15 @@ import org.briarproject.bramble.system.AndroidSystemModule;
 import dagger.Module;
 
 @Module(includes = {
+		AndroidBatteryModule.class,
 		AndroidNetworkModule.class,
 		AndroidSystemModule.class,
 		CircumventionModule.class
 })
 public class BrambleAndroidModule {
 
+	public static void initEagerSingletons(BrambleAndroidEagerSingletons c) {
+		c.inject(new AndroidBatteryModule.EagerSingletons());
+		c.inject(new AndroidNetworkModule.EagerSingletons());
+	}
 }

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

@@ -12,11 +12,15 @@ import org.briarproject.bramble.api.identity.IdentityManager;
 import org.briarproject.bramble.util.IoUtils;
 
 import java.io.File;
+import java.util.HashSet;
+import java.util.Set;
 import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
+import static android.os.Build.VERSION.SDK_INT;
+
 class AndroidAccountManager extends AccountManagerImpl
 		implements AccountManager {
 
@@ -89,20 +93,42 @@ class AndroidAccountManager extends AccountManagerImpl
 				LOG.warning("Could not clear shared preferences");
 		}
 		// Delete files, except lib and shared_prefs directories
+		Set<File> files = new HashSet<>();
 		File dataDir = new File(appContext.getApplicationInfo().dataDir);
-		File[] children = dataDir.listFiles();
-		if (children == null) {
+		@Nullable
+		File[] fileArray = dataDir.listFiles();
+		if (fileArray == null) {
 			LOG.warning("Could not list files in app data dir");
 		} else {
-			for (File child : children) {
-				String name = child.getName();
+			for (File file : fileArray) {
+				String name = file.getName();
 				if (!name.equals("lib") && !name.equals("shared_prefs")) {
-					IoUtils.deleteFileOrDir(child);
+					files.add(file);
 				}
 			}
 		}
+		files.add(appContext.getFilesDir());
+		files.add(appContext.getCacheDir());
+		addIfNotNull(files, appContext.getExternalCacheDir());
+		if (SDK_INT >= 19) {
+			for (File file : appContext.getExternalCacheDirs()) {
+				addIfNotNull(files, file);
+			}
+		}
+		if (SDK_INT >= 21) {
+			for (File file : appContext.getExternalMediaDirs()) {
+				addIfNotNull(files, file);
+			}
+		}
+		for (File file : files) {
+			IoUtils.deleteFileOrDir(file);
+		}
 		// Recreate the cache dir as some OpenGL drivers expect it to exist
-		if (!new File(dataDir, "cache").mkdir())
+		if (!new File(dataDir, "cache").mkdirs())
 			LOG.warning("Could not recreate cache dir");
 	}
+
+	private void addIfNotNull(Set<File> files, @Nullable File file) {
+		if (file != null) files.add(file);
+	}
 }

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

@@ -0,0 +1,81 @@
+package org.briarproject.bramble.battery;
+
+import android.app.Application;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.battery.event.BatteryEvent;
+import org.briarproject.bramble.api.event.EventBus;
+import org.briarproject.bramble.api.lifecycle.Service;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.logging.Logger;
+
+import javax.inject.Inject;
+
+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 java.util.logging.Level.INFO;
+import static java.util.logging.Logger.getLogger;
+
+class AndroidBatteryManager implements BatteryManager, Service {
+
+	private static final Logger LOG =
+			getLogger(AndroidBatteryManager.class.getName());
+
+	private final Context appContext;
+	private final EventBus eventBus;
+	private final AtomicBoolean used = new AtomicBoolean(false);
+
+	private volatile BroadcastReceiver batteryReceiver = null;
+
+	@Inject
+	AndroidBatteryManager(Application app, EventBus eventBus) {
+		this.appContext = app.getApplicationContext();
+		this.eventBus = eventBus;
+	}
+
+	@Override
+	public boolean isCharging() {
+		// Get the sticky intent for ACTION_BATTERY_CHANGED
+		IntentFilter filter = new IntentFilter(ACTION_BATTERY_CHANGED);
+		Intent i = appContext.registerReceiver(null, filter);
+		if (i == null) return false;
+		int status = i.getIntExtra(EXTRA_PLUGGED, 0);
+		return status != 0;
+	}
+
+	@Override
+	public void startService() {
+		if (used.getAndSet(true)) throw new IllegalStateException();
+		batteryReceiver = new BatteryReceiver();
+		IntentFilter filter = new IntentFilter();
+		filter.addAction(ACTION_POWER_CONNECTED);
+		filter.addAction(ACTION_POWER_DISCONNECTED);
+		appContext.registerReceiver(batteryReceiver, filter);
+	}
+
+	@Override
+	public void stopService() {
+		if (batteryReceiver != null)
+			appContext.unregisterReceiver(batteryReceiver);
+	}
+
+	private class BatteryReceiver extends BroadcastReceiver {
+
+		@Override
+		public void onReceive(Context ctx, Intent i) {
+			String action = i.getAction();
+			if (LOG.isLoggable(INFO)) LOG.info("Received broadcast " + action);
+			if (ACTION_POWER_CONNECTED.equals(action))
+				eventBus.broadcast(new BatteryEvent(true));
+			else if (ACTION_POWER_DISCONNECTED.equals(action))
+				eventBus.broadcast(new BatteryEvent(false));
+		}
+	}
+}

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

@@ -0,0 +1,27 @@
+package org.briarproject.bramble.battery;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class AndroidBatteryModule {
+
+	public static class EagerSingletons {
+		@Inject
+		BatteryManager batteryManager;
+	}
+
+	@Provides
+	@Singleton
+	BatteryManager provideBatteryManager(LifecycleManager lifecycleManager,
+			AndroidBatteryManager batteryManager) {
+		lifecycleManager.registerService(batteryManager);
+		return batteryManager;
+	}
+}

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

@@ -3,6 +3,7 @@ package org.briarproject.bramble.network;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.network.NetworkManager;
 
+import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import dagger.Module;
@@ -11,6 +12,11 @@ import dagger.Provides;
 @Module
 public class AndroidNetworkModule {
 
+	public static class EagerSingletons {
+		@Inject
+		NetworkManager networkManager;
+	}
+
 	@Provides
 	@Singleton
 	NetworkManager provideNetworkManager(LifecycleManager lifecycleManager,

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

@@ -16,18 +16,27 @@ import org.briarproject.bramble.api.plugin.PluginException;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.util.AndroidUtils;
+import org.briarproject.bramble.util.IoUtils;
 
-import java.io.Closeable;
 import java.io.IOException;
 import java.security.SecureRandom;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
 import java.util.UUID;
+import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
+import java.util.concurrent.LinkedBlockingQueue;
 import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
 
+import static android.bluetooth.BluetoothAdapter.ACTION_DISCOVERY_FINISHED;
+import static android.bluetooth.BluetoothAdapter.ACTION_DISCOVERY_STARTED;
 import static android.bluetooth.BluetoothAdapter.ACTION_SCAN_MODE_CHANGED;
 import static android.bluetooth.BluetoothAdapter.ACTION_STATE_CHANGED;
 import static android.bluetooth.BluetoothAdapter.EXTRA_SCAN_MODE;
@@ -37,8 +46,12 @@ import static android.bluetooth.BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERA
 import static android.bluetooth.BluetoothAdapter.SCAN_MODE_NONE;
 import static android.bluetooth.BluetoothAdapter.STATE_OFF;
 import static android.bluetooth.BluetoothAdapter.STATE_ON;
+import static android.bluetooth.BluetoothDevice.ACTION_FOUND;
+import static android.bluetooth.BluetoothDevice.EXTRA_DEVICE;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.util.LogUtils.logException;
+import static org.briarproject.bramble.util.PrivacyUtils.scrubMacAddress;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault
@@ -47,8 +60,11 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 	private static final Logger LOG =
 			Logger.getLogger(AndroidBluetoothPlugin.class.getName());
 
+	private static final int MAX_DISCOVERY_MS = 10_000;
+
 	private final AndroidExecutor androidExecutor;
 	private final Context appContext;
+	private final Clock clock;
 
 	private volatile boolean wasEnabledByUs = false;
 	private volatile BluetoothStateReceiver receiver = null;
@@ -58,12 +74,13 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 
 	AndroidBluetoothPlugin(BluetoothConnectionLimiter connectionLimiter,
 			Executor ioExecutor, AndroidExecutor androidExecutor,
-			Context appContext, SecureRandom secureRandom, Backoff backoff,
-			DuplexPluginCallback callback, int maxLatency) {
+			Context appContext, SecureRandom secureRandom, Clock clock,
+			Backoff backoff, DuplexPluginCallback callback, int maxLatency) {
 		super(connectionLimiter, ioExecutor, secureRandom, backoff, callback,
 				maxLatency);
 		this.androidExecutor = androidExecutor;
 		this.appContext = appContext;
+		this.clock = clock;
 	}
 
 	@Override
@@ -143,11 +160,7 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 
 	@Override
 	void tryToClose(@Nullable BluetoothServerSocket ss) {
-		try {
-			if (ss != null) ss.close();
-		} catch (IOException e) {
-			logException(LOG, WARNING, e);
-		}
+		IoUtils.tryToClose(ss, LOG, WARNING);
 	}
 
 	@Override
@@ -177,17 +190,77 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 			s.connect();
 			return wrapSocket(s);
 		} catch (IOException e) {
-			tryToClose(s);
+			IoUtils.tryToClose(s, LOG, WARNING);
 			throw e;
 		}
 	}
 
-	private void tryToClose(@Nullable Closeable c) {
-		try {
-			if (c != null) c.close();
-		} catch (IOException e) {
-			logException(LOG, WARNING, e);
+	@Override
+	@Nullable
+	DuplexTransportConnection discoverAndConnect(String uuid) {
+		if (adapter == null) return null;
+		for (String address : discoverDevices()) {
+			try {
+				if (LOG.isLoggable(INFO))
+					LOG.info("Connecting to " + scrubMacAddress(address));
+				return connectTo(address, uuid);
+			} catch (IOException e) {
+				if (LOG.isLoggable(INFO)) {
+					LOG.info("Could not connect to "
+							+ scrubMacAddress(address));
+				}
+			}
 		}
+		LOG.info("Could not connect to any devices");
+		return null;
+	}
+
+	private Collection<String> discoverDevices() {
+		List<String> addresses = new ArrayList<>();
+		BlockingQueue<Intent> intents = new LinkedBlockingQueue<>();
+		DiscoveryReceiver receiver = new DiscoveryReceiver(intents);
+		IntentFilter filter = new IntentFilter();
+		filter.addAction(ACTION_DISCOVERY_STARTED);
+		filter.addAction(ACTION_DISCOVERY_FINISHED);
+		filter.addAction(ACTION_FOUND);
+		appContext.registerReceiver(receiver, filter);
+		try {
+			if (adapter.startDiscovery()) {
+				long now = clock.currentTimeMillis();
+				long end = now + MAX_DISCOVERY_MS;
+				while (now < end) {
+					Intent i = intents.poll(end - now, MILLISECONDS);
+					if (i == null) break;
+					String action = i.getAction();
+					if (ACTION_DISCOVERY_STARTED.equals(action)) {
+						LOG.info("Discovery started");
+					} else if (ACTION_DISCOVERY_FINISHED.equals(action)) {
+						LOG.info("Discovery finished");
+						break;
+					} else if (ACTION_FOUND.equals(action)) {
+						BluetoothDevice d = i.getParcelableExtra(EXTRA_DEVICE);
+						String address = d.getAddress();
+						if (LOG.isLoggable(INFO))
+							LOG.info("Discovered " + scrubMacAddress(address));
+						if (!addresses.contains(address))
+							addresses.add(address);
+					}
+					now = clock.currentTimeMillis();
+				}
+			} else {
+				LOG.info("Could not start discovery");
+			}
+		} catch (InterruptedException e) {
+			LOG.info("Interrupted while discovering devices");
+			Thread.currentThread().interrupt();
+		} finally {
+			LOG.info("Cancelling discovery");
+			adapter.cancelDiscovery();
+			appContext.unregisterReceiver(receiver);
+		}
+		// Shuffle the addresses so we don't always try the same one first
+		Collections.shuffle(addresses);
+		return addresses;
 	}
 
 	private class BluetoothStateReceiver extends BroadcastReceiver {
@@ -207,4 +280,18 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 			}
 		}
 	}
+
+	private static class DiscoveryReceiver extends BroadcastReceiver {
+
+		private final BlockingQueue<Intent> intents;
+
+		private DiscoveryReceiver(BlockingQueue<Intent> intents) {
+			this.intents = intents;
+		}
+
+		@Override
+		public void onReceive(Context ctx, Intent intent) {
+			intents.add(intent);
+		}
+	}
 }

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

@@ -11,6 +11,7 @@ import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
 import org.briarproject.bramble.api.system.AndroidExecutor;
+import org.briarproject.bramble.api.system.Clock;
 
 import java.security.SecureRandom;
 import java.util.concurrent.Executor;
@@ -33,17 +34,19 @@ public class AndroidBluetoothPluginFactory implements DuplexPluginFactory {
 	private final Context appContext;
 	private final SecureRandom secureRandom;
 	private final EventBus eventBus;
+	private final Clock clock;
 	private final BackoffFactory backoffFactory;
 
 	public AndroidBluetoothPluginFactory(Executor ioExecutor,
 			AndroidExecutor androidExecutor, Context appContext,
-			SecureRandom secureRandom, EventBus eventBus,
+			SecureRandom secureRandom, EventBus eventBus, Clock clock,
 			BackoffFactory backoffFactory) {
 		this.ioExecutor = ioExecutor;
 		this.androidExecutor = androidExecutor;
 		this.appContext = appContext;
 		this.secureRandom = secureRandom;
 		this.eventBus = eventBus;
+		this.clock = clock;
 		this.backoffFactory = backoffFactory;
 	}
 
@@ -65,7 +68,7 @@ public class AndroidBluetoothPluginFactory implements DuplexPluginFactory {
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
 		AndroidBluetoothPlugin plugin = new AndroidBluetoothPlugin(
 				connectionLimiter, ioExecutor, androidExecutor, appContext,
-				secureRandom, backoff, callback, MAX_LATENCY);
+				secureRandom, clock, backoff, callback, MAX_LATENCY);
 		eventBus.addListener(plugin);
 		return plugin;
 	}

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

@@ -6,6 +6,7 @@ import android.content.pm.PackageManager;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.os.PowerManager;
 
+import org.briarproject.bramble.api.battery.BatteryManager;
 import org.briarproject.bramble.api.network.NetworkManager;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
@@ -41,17 +42,18 @@ class AndroidTorPlugin extends TorPlugin {
 			Context appContext, NetworkManager networkManager,
 			LocationUtils locationUtils, SocketFactory torSocketFactory,
 			Clock clock, ResourceProvider resourceProvider,
-			CircumventionProvider circumventionProvider, Backoff backoff,
+			CircumventionProvider circumventionProvider,
+			BatteryManager batteryManager, Backoff backoff,
 			DuplexPluginCallback callback, String architecture, int maxLatency,
 			int maxIdleTime) {
 		super(ioExecutor, networkManager, locationUtils, torSocketFactory,
-				clock, resourceProvider, circumventionProvider, backoff,
-				callback, architecture, maxLatency, maxIdleTime,
+				clock, resourceProvider, circumventionProvider, batteryManager,
+				backoff, callback, architecture, maxLatency, maxIdleTime,
 				appContext.getDir("tor", MODE_PRIVATE));
 		this.appContext = appContext;
 		PowerManager pm = (PowerManager)
 				appContext.getSystemService(POWER_SERVICE);
-		assert pm != null;
+		if (pm == null) throw new AssertionError();
 		wakeLock = new RenewableWakeLock(pm, scheduler, PARTIAL_WAKE_LOCK,
 				WAKE_LOCK_TAG, 1, MINUTES);
 	}

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

@@ -3,6 +3,7 @@ package org.briarproject.bramble.plugin.tor;
 import android.content.Context;
 import android.os.Build;
 
+import org.briarproject.bramble.api.battery.BatteryManager;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.network.NetworkManager;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
@@ -48,6 +49,7 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 	private final BackoffFactory backoffFactory;
 	private final ResourceProvider resourceProvider;
 	private final CircumventionProvider circumventionProvider;
+	private final BatteryManager batteryManager;
 	private final Clock clock;
 
 	public AndroidTorPluginFactory(Executor ioExecutor,
@@ -55,7 +57,8 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 			NetworkManager networkManager, LocationUtils locationUtils,
 			EventBus eventBus, SocketFactory torSocketFactory,
 			BackoffFactory backoffFactory, ResourceProvider resourceProvider,
-			CircumventionProvider circumventionProvider, Clock clock) {
+			CircumventionProvider circumventionProvider,
+			BatteryManager batteryManager, Clock clock) {
 		this.ioExecutor = ioExecutor;
 		this.scheduler = scheduler;
 		this.appContext = appContext;
@@ -66,6 +69,7 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 		this.backoffFactory = backoffFactory;
 		this.resourceProvider = resourceProvider;
 		this.circumventionProvider = circumventionProvider;
+		this.batteryManager = batteryManager;
 		this.clock = clock;
 	}
 
@@ -104,8 +108,8 @@ public class AndroidTorPluginFactory implements DuplexPluginFactory {
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
 		AndroidTorPlugin plugin = new AndroidTorPlugin(ioExecutor, scheduler,
 				appContext, networkManager, locationUtils, torSocketFactory,
-				clock, resourceProvider, circumventionProvider, backoff,
-				callback, architecture, MAX_LATENCY, MAX_IDLE_TIME);
+				clock, resourceProvider, circumventionProvider, batteryManager,
+				backoff, callback, architecture, MAX_LATENCY, MAX_IDLE_TIME);
 		eventBus.addListener(plugin);
 		return plugin;
 	}

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

@@ -1,5 +1,6 @@
 package org.briarproject.bramble.system;
 
+import android.annotation.SuppressLint;
 import android.app.Application;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
@@ -26,7 +27,7 @@ import static android.provider.Settings.Secure.ANDROID_ID;
 
 @Immutable
 @NotNullByDefault
-class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
+class AndroidSecureRandomProvider extends UnixSecureRandomProvider {
 
 	private static final int SEED_LENGTH = 32;
 
@@ -37,6 +38,7 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 		appContext = app.getApplicationContext();
 	}
 
+	@SuppressLint("HardwareIds")
 	@Override
 	protected void writeToEntropyPool(DataOutputStream out) throws IOException {
 		super.writeToEntropyPool(out);
@@ -49,12 +51,14 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 		String id = Settings.Secure.getString(contentResolver, ANDROID_ID);
 		if (id != null) out.writeUTF(id);
 		Parcel parcel = Parcel.obtain();
-		WifiManager wm =
-				(WifiManager) appContext.getSystemService(WIFI_SERVICE);
-		List<WifiConfiguration> configs = wm.getConfiguredNetworks();
-		if (configs != null) {
-			for (WifiConfiguration config : configs)
-				parcel.writeParcelable(config, 0);
+		WifiManager wm = (WifiManager) appContext.getApplicationContext()
+				.getSystemService(WIFI_SERVICE);
+		if (wm != null) {
+			List<WifiConfiguration> configs = wm.getConfiguredNetworks();
+			if (configs != null) {
+				for (WifiConfiguration config : configs)
+					parcel.writeParcelable(config, 0);
+			}
 		}
 		BluetoothAdapter bt = BluetoothAdapter.getDefaultAdapter();
 		if (bt != null) {
@@ -77,13 +81,13 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 
 	// Based on https://android-developers.googleblog.com/2013/08/some-securerandom-thoughts.html
 	private void applyOpenSslFix() {
-		byte[] seed = new LinuxSecureRandomSpi().engineGenerateSeed(
+		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, seed);
+					.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")

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

@@ -11,15 +11,12 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
-import java.util.logging.Logger;
 
 import static android.content.Context.MODE_PRIVATE;
+import static android.os.Build.VERSION.SDK_INT;
 
 public class AndroidUtils {
 
-	private static final Logger LOG =
-			Logger.getLogger(AndroidUtils.class.getName());
-
 	// Fake Bluetooth address returned by BluetoothAdapter on API 23 and later
 	private static final String FAKE_BLUETOOTH_ADDRESS = "02:00:00:00:00:00";
 
@@ -28,7 +25,7 @@ public class AndroidUtils {
 	@SuppressWarnings("deprecation")
 	public static Collection<String> getSupportedArchitectures() {
 		List<String> abis = new ArrayList<>();
-		if (Build.VERSION.SDK_INT >= 21) {
+		if (SDK_INT >= 21) {
 			abis.addAll(Arrays.asList(Build.SUPPORTED_ABIS));
 		} else {
 			abis.add(Build.CPU_ABI);

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

@@ -112,6 +112,8 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 		// Other directories should be deleted
 		File potatoDir = new File(testDir, ".potato");
 		File potatoFile = new File(potatoDir, "file");
+		File filesDir = new File(testDir, "filesDir");
+		File externalCacheDir = new File(testDir, "externalCacheDir");
 
 		context.checking(new Expectations() {{
 			oneOf(prefs).edit();
@@ -128,6 +130,12 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 			will(returnValue(true));
 			oneOf(app).getApplicationInfo();
 			will(returnValue(applicationInfo));
+			oneOf(app).getFilesDir();
+			will(returnValue(filesDir));
+			oneOf(app).getCacheDir();
+			will(returnValue(cacheDir));
+			oneOf(app).getExternalCacheDir();
+			will(returnValue(externalCacheDir));
 		}});
 
 		assertTrue(dbDir.mkdirs());
@@ -140,6 +148,8 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 		assertTrue(cacheFile.createNewFile());
 		assertTrue(potatoDir.mkdirs());
 		assertTrue(potatoFile.createNewFile());
+		assertTrue(filesDir.mkdirs());
+		assertTrue(externalCacheDir.mkdirs());
 
 		accountManager.deleteAccount();
 
@@ -153,6 +163,8 @@ public class AndroidAccountManagerTest extends BrambleMockTestCase {
 		assertFalse(cacheFile.exists());
 		assertFalse(potatoDir.exists());
 		assertFalse(potatoFile.exists());
+		assertFalse(filesDir.exists());
+		assertFalse(externalCacheDir.exists());
 	}
 
 	@After

bramble-android/witness.gradle

@@ -1,50 +1,55 @@
 dependencyVerification {
     verify = [
         'cglib:cglib:3.2.0:cglib-3.2.0.jar:adb13bab79712ad6bdf1bd59f2a3918018a8016e722e8a357065afb9e6690861',
-        'com.android.tools.analytics-library:protos:26.1.3:protos-26.1.3.jar:818c9f256f141d9dafec03a1aa2b94d240b2c140acfd7ee31a8b3e6c2b9479e3',
-        'com.android.tools.analytics-library:shared:26.1.3:shared-26.1.3.jar:7110706c7ada96c8b6f5ca80c478291bc7899d46277de2c48527e045442401a3',
-        'com.android.tools.analytics-library:tracker:26.1.3:tracker-26.1.3.jar:4155424bf2ce4872da83332579a1707252bc66cbd77c5144fdc4483d0f2e1418',
-        'com.android.tools.build:apksig:3.1.3:apksig-3.1.3.jar:7e1f8e675a6e768e5b56405e41d6c3cc05befe62e601b04177de1029902c9c89',
-        'com.android.tools.build:builder-model:3.1.3:builder-model-3.1.3.jar:06ad1c422d679fc698451479cb40ba863849d67bfd1de23f6d2c16d78b024b0b',
-        'com.android.tools.build:builder-test-api:3.1.3:builder-test-api-3.1.3.jar:4d989f780436794f0f8b2f50e9e079b786571eac90f26c208ab2ae6d4012f389',
-        'com.android.tools.build:builder:3.1.3:builder-3.1.3.jar:8a1092012c89d0ec1ee2eff09c5708c71ef4482a6862df8d3a44a67fccace01c',
-        'com.android.tools.build:gradle-api:3.1.3:gradle-api-3.1.3.jar:01e4df521456aef66514336f1d492346730dd1fb8f6433a89f62da834941ed72',
-        'com.android.tools.build:manifest-merger:26.1.3:manifest-merger-26.1.3.jar:1e4fc7e932adb4607082409800e5e6fccb42e6c5360ae5990094bf522f3ada55',
-        'com.android.tools.ddms:ddmlib:26.1.3:ddmlib-26.1.3.jar:c54931cd68df5d1ea2923b3b320eae47cd2307a5a916bb8674c0acf93cd1d3cd',
-        'com.android.tools.external.com-intellij:intellij-core:26.1.3:intellij-core-26.1.3.jar:af67f5535fef2e1a28b1007a4acb8c5deb6a1e33b8afe7b11d012c9e778ebcec',
-        'com.android.tools.external.com-intellij:kotlin-compiler:26.1.3:kotlin-compiler-26.1.3.jar:c746d2859dc11cc05c84b692b3498d3a621e0929511f8440ee009c6557838fd4',
-        'com.android.tools.external.org-jetbrains:uast:26.1.3:uast-26.1.3.jar:3f3f6651d0c7685a77ecb22e9c82d6b49fdf24322c17360768dc530678f43265',
-        'com.android.tools.layoutlib:layoutlib-api:26.1.3:layoutlib-api-26.1.3.jar:10bc73ce706c45629872d6a999dbe12116df64e24f47ff93b7b13121ff57b4b0',
-        'com.android.tools.lint:lint-api:26.1.3:lint-api-26.1.3.jar:6f97323f9af8deda86278717885b5c927f3766757db89709f52d11d42b6fb751',
-        'com.android.tools.lint:lint-checks:26.1.3:lint-checks-26.1.3.jar:73c3d53784c9ce3e6d5968506581918e0179645d20809927ca4a001dd766b001',
-        'com.android.tools.lint:lint-gradle-api:26.1.3:lint-gradle-api-26.1.3.jar:7ca3c4866ec21dc21d53a9d86f752b77ace6f6c610a0c9dc877313856c733d9d',
-        'com.android.tools.lint:lint-gradle:26.1.3:lint-gradle-26.1.3.jar:db0c354b8f4b6f6637e31f91c564785a59ff896325331fcbc3de7458e0b6c067',
-        'com.android.tools.lint:lint-kotlin:26.1.3:lint-kotlin-26.1.3.jar:94e2b0f4565a241561cfb8fc1222bb3f132a3b98d2a90421dbb72ee8358e7d68',
-        'com.android.tools.lint:lint:26.1.3:lint-26.1.3.jar:8d5f32c989c6d191d712e90ad3ca2d1c409313599551d04d834caa44d26c78df',
-        'com.android.tools:annotations:26.1.3:annotations-26.1.3.jar:c950430b24ac5d58fc97e7283b8f0115f99587e76e08b4e1e2aaa780f2d77323',
-        'com.android.tools:common:26.1.3:common-26.1.3.jar:7c31a90581a148ab219f615a59667f0dded7fa39b248529784474da3c2274ef2',
-        'com.android.tools:dvlib:26.1.3:dvlib-26.1.3.jar:0cae87906f53d3f1088366a916ed180a7312b6d9919b90797f238875c8492855',
-        'com.android.tools:repository:26.1.3:repository-26.1.3.jar:52d4539cc68db91b261e2a33b2c8206b26e05539078758dc28cfb3854adb4f59',
-        'com.android.tools:sdk-common:26.1.3:sdk-common-26.1.3.jar:1948603ca9ff22c7ebb3178000bffa3a9dd2ca1cc5cb0c793cae08468b8fcfc1',
-        'com.android.tools:sdklib:26.1.3:sdklib-26.1.3.jar:4adcfaad9514607098d2c51503c39811112d3050f4d1e744c01c7f08f591032b',
+        'com.android.tools.analytics-library:protos:26.3.2:protos-26.3.2.jar:50238fb4298b297217b184b9cd93c14f83536fcee829eb0ca850bdb5b53251f0',
+        'com.android.tools.analytics-library:shared:26.3.2:shared-26.3.2.jar:ddd80dcf21905018b7c0583ba72b7282f446084d4952422609a09fbf8237ef71',
+        'com.android.tools.analytics-library:tracker:26.3.2:tracker-26.3.2.jar:28c575d2d1af003e96d7b375a668ee10b2673a2dd0f6438750aa8c3b42e7d0ad',
+        'com.android.tools.build:apksig:3.3.2:apksig-3.3.2.jar:84c4aaa20127c6c1fe6bdd334b3f5df71f54ad080be9029c8a10f43b6a908acd',
+        'com.android.tools.build:apkzlib:3.3.2:apkzlib-3.3.2.jar:d34e523278e5dff565eba3ef3c089d515b2b5cc7b47dc77e2f3465e5e47176ac',
+        'com.android.tools.build:builder-model:3.3.2:builder-model-3.3.2.jar:055e3db0ecee9e06b9f024034999a29cd92cb1885207b37542126bd8bcc57f46',
+        'com.android.tools.build:builder-test-api:3.3.2:builder-test-api-3.3.2.jar:0b2e4cd7615bbcad14a3c91fe45ae26693508d06e40ba06c5968b8bc24416618',
+        'com.android.tools.build:builder:3.3.2:builder-3.3.2.jar:65649704da7aef0487235fd326f0f2e99ed5cf958e80f204496e6e08a42bd9f5',
+        'com.android.tools.build:gradle-api:3.3.2:gradle-api-3.3.2.jar:3cbd47e41bb70330dd72ec2c9fe51e6173554b484a03829b5a2de9e00841e040',
+        'com.android.tools.build:manifest-merger:26.3.2:manifest-merger-26.3.2.jar:05c4a6d8b02fb9f08744876477d0a68547c03a8a9069b1f086684fa04af97c33',
+        'com.android.tools.ddms:ddmlib:26.3.2:ddmlib-26.3.2.jar:d248da8a563d6e46d2c7ebbf371a4877e00510f4ca763c0bb272d5a281bf8b85',
+        'com.android.tools.external.com-intellij:intellij-core:26.3.2:intellij-core-26.3.2.jar:6c5ecc968230e9f4dcd0fef28885379feace1f0cd8130de6f61d649c86139bf3',
+        'com.android.tools.external.com-intellij:kotlin-compiler:26.3.2:kotlin-compiler-26.3.2.jar:1007d9b07ccb49cd8eaf30fda10ed4681d4714f2f9ab2ecda39b4e539cc51bbe',
+        'com.android.tools.external.org-jetbrains:uast:26.3.2:uast-26.3.2.jar:5d1833e562ea4f38a89708dfde695f0a162cbd39d003d3dde818c3fdc2b05317',
+        'com.android.tools.layoutlib:layoutlib-api:26.3.2:layoutlib-api-26.3.2.jar:d7e61e874ab95f5c350dd38b6a95b5c9dbe0083a02001884264cdb390cb255b8',
+        'com.android.tools.lint:lint-api:26.3.2:lint-api-26.3.2.jar:5867dfd7fb4a4e161a816a5d29d045f9b542d34594c00a1efec46fb4cd0e1033',
+        'com.android.tools.lint:lint-checks:26.3.2:lint-checks-26.3.2.jar:4b163b9c93790d2771e92ba8de58a0d9e0671ffcf2ccef3cf496efd442e27517',
+        'com.android.tools.lint:lint-gradle-api:26.3.2:lint-gradle-api-26.3.2.jar:54cb282e0c054f9bed3f51302ce08b003c8ab7961dfd5a4f6de26c23cc23062f',
+        'com.android.tools.lint:lint-gradle:26.3.2:lint-gradle-26.3.2.jar:bb139615f4ce97d42cc394b9389b49b76a6eb85be6785a5d272991543b519013',
+        'com.android.tools.lint:lint:26.3.2:lint-26.3.2.jar:ef7b369f8a56a92ccb0f4c1c357666b9339e4a711a9d84747d446441746cfe4e',
+        'com.android.tools:annotations:26.3.2:annotations-26.3.2.jar:5bcce8e98b6a2f5ccf13ebcefd8f734e0b35f8b19e456575665631442ce1f7a1',
+        'com.android.tools:common:26.3.2:common-26.3.2.jar:d9f8e7f0669e9a701568e3db6a87c89cf12d8fa6811c9991e969f950215ecfac',
+        'com.android.tools:dvlib:26.3.2:dvlib-26.3.2.jar:d84aad56161c7773579303d69714ded6897c64c6ddfd7d456e453231e4dfe811',
+        'com.android.tools:repository:26.3.2:repository-26.3.2.jar:da611eeb06e9ab8750d25b9e2901e10db8e5ec6304eb4c8b7103d39e0921ea40',
+        'com.android.tools:sdk-common:26.3.2:sdk-common-26.3.2.jar:82823a3bf25e64fac33a286490f0cf5ac50c2cdb3c540149b030896bb44bf96c',
+        'com.android.tools:sdklib:26.3.2:sdklib-26.3.2.jar:424d15492af67321900963238646d27495ab60de2a5b19e6a416963bc5d6932b',
         'com.google.code.findbugs:jsr305:1.3.9:jsr305-1.3.9.jar:905721a0eea90a81534abb7ee6ef4ea2e5e645fa1def0a5cd88402df1b46c9ed',
-        'com.google.code.gson:gson:2.7:gson-2.7.jar:2d43eb5ea9e133d2ee2405cc14f5ee08951b8361302fdd93494a3a997b508d32',
-        'com.google.dagger:dagger-compiler:2.0.2:dagger-compiler-2.0.2.jar:b74bc9de063dd4c6400b232231f2ef5056145b8fbecbf5382012007dd1c071b3',
-        'com.google.dagger:dagger-producers:2.0-beta:dagger-producers-2.0-beta.jar:99ec15e8a0507ba569e7655bc1165ee5e5ca5aa914b3c8f7e2c2458f724edd6b',
-        'com.google.dagger:dagger:2.0.2:dagger-2.0.2.jar:84c0282ed8be73a29e0475d639da030b55dee72369e58dd35ae7d4fe6243dcf9',
-        'com.google.errorprone:error_prone_annotations:2.0.18:error_prone_annotations-2.0.18.jar:cb4cfad870bf563a07199f3ebea5763f0dec440fcda0b318640b1feaa788656b',
-        'com.google.guava:guava:18.0:guava-18.0.jar:d664fbfc03d2e5ce9cab2a44fb01f1d0bf9dfebeccc1a473b1f9ea31f79f6f99',
-        'com.google.guava:guava:22.0:guava-22.0.jar:1158e94c7de4da480873f0b4ab4a1da14c0d23d4b1902cc94a58a6f0f9ab579e',
+        'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
+        'com.google.code.gson:gson:2.8.0:gson-2.8.0.jar:c6221763bd79c4f1c3dc7f750b5f29a0bb38b367b81314c4f71896e340c40825',
+        'com.google.dagger:dagger-compiler:2.19:dagger-compiler-2.19.jar:27a4b202a2de908182edb261f8c0a264e08e5e4733d7514bc7fbf0d31da5c0fc',
+        'com.google.dagger:dagger-producers:2.19:dagger-producers-2.19.jar:a17663abe0fc38b676026950907d4c5f5e2bf338375415861eaff6e3bdb0b768',
+        'com.google.dagger:dagger-spi:2.19:dagger-spi-2.19.jar:e7a6379d82c841f6aac2866948ad1eed716528707814602842a8d844ce04e2e1',
+        'com.google.dagger:dagger:2.19:dagger-2.19.jar:514b6f1e0727c6572e1d65cb27e4ae668b7aeaeb93a29515182965265b609939',
+        'com.google.errorprone:error_prone_annotations:2.1.3:error_prone_annotations-2.1.3.jar:03d0329547c13da9e17c634d1049ea2ead093925e290567e1a364fd6b1fc7ff8',
+        '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:guava:25.0-jre:guava-25.0-jre.jar:3fd4341776428c7e0e5c18a7c10de129475b69ab9d30aeafbb5c277bb6074fa9',
+        'com.google.guava:guava:26.0-jre:guava-26.0-jre.jar:a0e9cabad665bc20bcd2b01f108e5fc03f756e13aea80abaadb9f407033bea2c',
         'com.google.j2objc:j2objc-annotations:1.1:j2objc-annotations-1.1.jar:40ceb7157feb263949e0f503fe5f71689333a621021aa20ce0d0acee3badaa0f',
         'com.google.jimfs:jimfs:1.1:jimfs-1.1.jar:c4828e28d7c0a930af9387510b3bada7daa5c04d7c25a75c7b8b081f1c257ddd',
         'com.google.protobuf:protobuf-java:3.4.0:protobuf-java-3.4.0.jar:dce7e66b32456a1b1198da0caff3a8acb71548658391e798c79369241e6490a4',
         'com.googlecode.json-simple:json-simple:1.1:json-simple-1.1.jar:2d9484f4c649f708f47f9a479465fc729770ee65617dca3011836602264f6439',
+        'com.squareup:javapoet:1.11.1:javapoet-1.11.1.jar:9cbf2107be499ec6e95afd36b58e3ca122a24166cdd375732e51267d64058e90',
         'com.squareup:javawriter:2.5.0:javawriter-2.5.0.jar:fcfb09fb0ea0aa97d3cfe7ea792398081348e468f126b3603cb3803f240197f0',
         'com.sun.activation:javax.activation:1.2.0:javax.activation-1.2.0.jar:993302b16cd7056f21e779cc577d175a810bb4900ef73cd8fbf2b50f928ba9ce',
         'com.sun.istack:istack-commons-runtime:2.21:istack-commons-runtime-2.21.jar:c33e67a0807095f02a0e2da139412dd7c4f9cc1a4c054b3e434f96831ba950f4',
         'com.sun.xml.fastinfoset:FastInfoset:1.2.13:FastInfoset-1.2.13.jar:27a77db909f3c2833c0b1a37c55af1db06045118ad2eed96ce567b6632bce038',
-        'commons-codec:commons-codec:1.6:commons-codec-1.6.jar:54b34e941b8e1414bd3e40d736efd3481772dc26db3296f6aa45cec9f6203d86',
-        'commons-logging:commons-logging:1.1.1:commons-logging-1.1.1.jar:ce6f913cad1f0db3aad70186d65c5bc7ffcc9a99e3fe8e0b137312819f7c362f',
+        'commons-codec:commons-codec:1.9:commons-codec-1.9.jar:ad19d2601c3abf0b946b5c3a4113e226a8c1e3305e395b90013b78dd94a723ce',
+        'commons-logging:commons-logging:1.2:commons-logging-1.2.jar:daddea1ea0be0f56978ab3006b8ac92834afeefbd9b7e4e6316fca57df0fa636',
         'it.unimi.dsi:fastutil:7.2.0:fastutil-7.2.0.jar:74fa208043740642f7e6eb09faba15965218ad2f50ce3020efb100136e4b591c',
         'javax.annotation:jsr250-api:1.0:jsr250-api-1.0.jar:a1a922d0d9b6d183ed3800dfac01d1e1eb159f0e8c6f94736931c1def54a941f',
         'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
@@ -55,24 +60,28 @@ dependencyVerification {
         'org.apache.ant:ant-launcher:1.9.4:ant-launcher-1.9.4.jar:7bccea20b41801ca17bcbc909a78c835d0f443f12d639c77bd6ae3d05861608d',
         'org.apache.ant:ant:1.9.4:ant-1.9.4.jar:649ae0730251de07b8913f49286d46bba7b92d47c5f332610aa426c4f02161d8',
         'org.apache.commons:commons-compress:1.12:commons-compress-1.12.jar:2c1542faf343185b7cab9c3d55c8ae5471d6d095d3887a4adefdbdf2984dc0b6',
-        'org.apache.httpcomponents:httpclient:4.2.6:httpclient-4.2.6.jar:362e9324ee7c697e21279e20077b52737ddef3f1b2c1a7abe5ad34b465145550',
-        'org.apache.httpcomponents:httpcore:4.2.5:httpcore-4.2.5.jar:e5e82da4cc66c8d917bbf743e3c0752efe8522735e7fc9dbddb65bccea81cfe9',
-        'org.apache.httpcomponents:httpmime:4.1:httpmime-4.1.jar:31629566148e8a47688ae43b420abc3ecd783ed15b33bebc00824bf24c9b15aa',
+        'org.apache.httpcomponents:httpclient:4.5.2:httpclient-4.5.2.jar:0dffc621400d6c632f55787d996b8aeca36b30746a716e079a985f24d8074057',
+        'org.apache.httpcomponents:httpcore:4.4.5:httpcore-4.4.5.jar:64d5453874cab7e40a7065cb01a9a9ca1053845a9786b478878b679e0580cec3',
+        'org.apache.httpcomponents:httpmime:4.5.2:httpmime-4.5.2.jar:231a3f7e4962053db2be8461d5422e68fc458a3a7dd7d8ada803a348e21f8f07',
         'org.beanshell:bsh:1.3.0:bsh-1.3.0.jar:9b04edc75d19db54f1b4e8b5355e9364384c6cf71eb0a1b9724c159d779879f8',
         'org.bouncycastle:bcpkix-jdk15on:1.56:bcpkix-jdk15on-1.56.jar:7043dee4e9e7175e93e0b36f45b1ec1ecb893c5f755667e8b916eb8dd201c6ca',
         'org.bouncycastle:bcprov-jdk15on:1.56:bcprov-jdk15on-1.56.jar:963e1ee14f808ffb99897d848ddcdb28fa91ddda867eb18d303e82728f878349',
-        'org.briarproject:tor-android:0.2.9.16:tor-android-0.2.9.16.zip:515e33dda6a30853c885a2de2c79ae1ab9ad8b6db44f5db8890333ec2e24f4ae',
-        'org.codehaus.groovy:groovy-all:2.4.12:groovy-all-2.4.12.jar:6a56af4bd48903d56bec62821876cadefafd007360cc6bd0d8f7aa8d72b38be4',
+        'org.briarproject:obfs4proxy-android:0.0.9:obfs4proxy-android-0.0.9.zip:9b7e9181535ea8d8bbe8ae6338e08cf4c5fc1e357a779393e0ce49586d459ae0',
+        'org.briarproject:tor-android:0.3.5.8:tor-android-0.3.5.8.zip:42a13a6f185be1a62f42e3f30ce66a3c099ac5ec890a65e7593111b65b44a54a',
+        'org.checkerframework:checker-compat-qual:2.5.3:checker-compat-qual-2.5.3.jar:d76b9afea61c7c082908023f0cbc1427fab9abd2df915c8b8a3e7a509bccbc6d',
+        'org.checkerframework:checker-qual:2.5.2:checker-qual-2.5.2.jar:64b02691c8b9d4e7700f8ee2e742dce7ea2c6e81e662b7522c9ee3bf568c040a',
+        'org.codehaus.groovy:groovy-all:2.4.15:groovy-all-2.4.15.jar:51d6c4e71782e85674239189499854359d380fb75e1a703756e3aaa5b98a5af0',
         'org.codehaus.mojo:animal-sniffer-annotations:1.14:animal-sniffer-annotations-1.14.jar:2068320bd6bad744c3673ab048f67e30bef8f518996fa380033556600669905d',
         'org.glassfish.jaxb:jaxb-core:2.2.11:jaxb-core-2.2.11.jar:37bcaee8ebb04362c8352a5bf6221b86967ecdab5164c696b10b9a2bb587b2aa',
         'org.glassfish.jaxb:jaxb-runtime:2.2.11:jaxb-runtime-2.2.11.jar:a874f2351cfba8e2946be3002d10c18a6da8f21b52ba2acf52f2b85d5520ed70',
         'org.glassfish.jaxb:txw2:2.2.11:txw2-2.2.11.jar:272a3ccad45a4511351920cd2a8633c53cab8d5220c7a92954da5526bb5eafea',
         'org.hamcrest:hamcrest-core:1.3:hamcrest-core-1.3.jar:66fdef91e9739348df7a096aa384a5685f4e875584cce89386a7a47251c4d8e9',
         'org.hamcrest:hamcrest-library:1.3:hamcrest-library-1.3.jar:711d64522f9ec410983bd310934296da134be4254a125080a0416ec178dfad1c',
-        'org.jetbrains.kotlin:kotlin-reflect:1.2.0:kotlin-reflect-1.2.0.jar:4f48a872bad6e4d9c053f4ad610d11e4012ad7e58dc19a03dd5eb811f36069dd',
-        'org.jetbrains.kotlin:kotlin-stdlib-jre7:1.2.0:kotlin-stdlib-jre7-1.2.0.jar:c7a20fb951d437797afe8980aff6c1e5a03f310c661ba58ba1d4fa90cb0f2926',
-        'org.jetbrains.kotlin:kotlin-stdlib-jre8:1.2.0:kotlin-stdlib-jre8-1.2.0.jar:633524eee6ef1941f7cb1dab7ee3927b0a221ceee9047aeb5515f4cbb990c82a',
-        'org.jetbrains.kotlin:kotlin-stdlib:1.2.0:kotlin-stdlib-1.2.0.jar:05cfd9f5ac0b41910703a8925f7211a495909b27a2ffdd1c5106f1689aeafcd4',
+        'org.jetbrains.kotlin:kotlin-reflect:1.3.21:kotlin-reflect-1.3.21.jar:a3065c822633191e0a3e3ee12a29bec234fc4b2864a6bb87ef48cce3e9e0c26a',
+        'org.jetbrains.kotlin:kotlin-stdlib-common:1.3.21:kotlin-stdlib-common-1.3.21.jar:cea61f7b611895e64f58569a9757fc0ab0d582f107211e1930e0ce2a0add52a7',
+        'org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.3.21:kotlin-stdlib-jdk7-1.3.21.jar:a87875604fd42140da6938ae4d35ee61081f4482536efc6d2615b8b626a198af',
+        'org.jetbrains.kotlin:kotlin-stdlib-jdk8:1.3.21:kotlin-stdlib-jdk8-1.3.21.jar:5823ed66ac122a1c55442ebca5a209a843ccd87f562edc31a787f3d2e47f74d4',
+        'org.jetbrains.kotlin:kotlin-stdlib:1.3.21:kotlin-stdlib-1.3.21.jar:38ba2370d9f06f50433e06b2ca775b94473c2e2785f410926079ab793c72b034',
         'org.jetbrains.trove4j:trove4j:20160824:trove4j-20160824.jar:1917871c8deb468307a584680c87a44572f5a8b0b98c6d397fc0f5f86596dbe7',
         'org.jetbrains:annotations:13.0:annotations-13.0.jar:ace2a10dc8e2d5fd34925ecac03e4988b2c0f851650c94b8cef49ba1bd111478',
         'org.jmock:jmock-junit4:2.8.2:jmock-junit4-2.8.2.jar:f7ee4df4f7bd7b7f1cafad3b99eb74d579f109d5992ff625347352edb55e674c',
@@ -81,11 +90,11 @@ dependencyVerification {
         'org.jmock:jmock:2.8.2:jmock-2.8.2.jar:6c73cb4a2e6dbfb61fd99c9a768539c170ab6568e57846bd60dbf19596b65b16',
         'org.jvnet.staxex:stax-ex:1.7.7:stax-ex-1.7.7.jar:a31ff7d77163c0deb09e7fee59ad35ae44c2cee2cc8552a116ccd1583d813fb4',
         'org.objenesis:objenesis:2.1:objenesis-2.1.jar:c74330cc6b806c804fd37e74487b4fe5d7c2750c5e15fbc6efa13bdee1bdef80',
-        'org.ow2.asm:asm-analysis:5.1:asm-analysis-5.1.jar:a34658f5c5de4b573eef21131cc32cc25f7b66407944f312b28ec2e56abb1fa9',
-        'org.ow2.asm:asm-commons:5.1:asm-commons-5.1.jar:97b3786e1f55e74bddf8ad102bf50e33bbcbc1f6b7fd7b36f0bbbb25cd4981be',
-        'org.ow2.asm:asm-tree:5.1:asm-tree-5.1.jar:c0de2bbc4cb8297419659813ecd4ed1d077ed1dd5c1f5544cc5143e493e84c10',
-        'org.ow2.asm:asm-util:5.1:asm-util-5.1.jar:ee032c39ae5e3cd099148fbba9a2124f9ed613e5cb93e03ee0fa8808ce364040',
+        'org.ow2.asm:asm-analysis:6.0:asm-analysis-6.0.jar:2f1a6387219c3a6cc4856481f221b03bd9f2408a326d416af09af5d6f608c1f4',
+        'org.ow2.asm:asm-commons:6.0:asm-commons-6.0.jar:f1bce5c648a96a017bdcd01fe5d59af9845297fd7b79b81c015a6fbbd9719abf',
+        'org.ow2.asm:asm-tree:6.0:asm-tree-6.0.jar:887998fb69727c8759e4d253f856822801e33f9fd4caa566b3ac58ee92106215',
+        'org.ow2.asm:asm-util:6.0:asm-util-6.0.jar:356afebdb0f870175262e5188f8709a3b17aa2a5a6a4b0340b04d4b449bca5f6',
         'org.ow2.asm:asm:5.0.4:asm-5.0.4.jar:896618ed8ae62702521a78bc7be42b7c491a08e6920a15f89a3ecdec31e9a220',
-        'org.ow2.asm:asm:5.1:asm-5.1.jar:d2da399a9967c69f0a21739256fa79d284222c223082cacadc17372244764b54',
+        'org.ow2.asm:asm:6.0:asm-6.0.jar:dd8971c74a4e697899a8e95caae4ea8760ea6c486dc6b97b1795e75760420461',
     ]
 }

bramble-api/build.gradle

@@ -7,15 +7,13 @@ apply plugin: 'witness'
 apply from: 'witness.gradle'
 
 dependencies {
-	implementation "com.google.dagger:dagger:2.0.2"
+	implementation "com.google.dagger:dagger:2.19"
 	implementation 'com.google.code.findbugs:jsr305:3.0.2'
 
 	testImplementation 'junit:junit:4.12'
 	testImplementation "org.jmock:jmock:2.8.2"
 	testImplementation "org.jmock:jmock-junit4:2.8.2"
 	testImplementation "org.jmock:jmock-legacy:2.8.2"
-	testImplementation "org.hamcrest:hamcrest-library:1.3"
-	testImplementation "org.hamcrest:hamcrest-core:1.3"
 
 	signature 'org.codehaus.mojo.signature:java16:1.1@signature'
 }

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

@@ -0,0 +1,26 @@
+package org.briarproject.bramble.api;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+
+@Immutable
+@NotNullByDefault
+public class Pair<A, B> {
+
+	private final A first;
+	private final B second;
+
+	public Pair(A first, B second) {
+		this.first = first;
+		this.second = second;
+	}
+
+	public A getFirst() {
+		return first;
+	}
+
+	public B getSecond() {
+		return second;
+	}
+}

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

@@ -38,4 +38,18 @@ public abstract class StringMap extends Hashtable<String, String> {
 	public void putInt(String key, int value) {
 		put(key, String.valueOf(value));
 	}
+
+	public long getLong(String key, long defaultValue) {
+		String s = get(key);
+		if (s == null) return defaultValue;
+		try {
+			return Long.valueOf(s);
+		} catch (NumberFormatException e) {
+			return defaultValue;
+		}
+	}
+
+	public void putLong(String key, long value) {
+		put(key, String.valueOf(value));
+	}
 }

bramble-api/src/main/java/org/briarproject/bramble/api/battery/BatteryManager.java

@@ -0,0 +1,6 @@
+package org.briarproject.bramble.api.battery;
+
+public interface BatteryManager {
+
+	boolean isCharging();
+}

bramble-api/src/main/java/org/briarproject/bramble/api/battery/event/BatteryEvent.java

@@ -0,0 +1,19 @@
+package org.briarproject.bramble.api.battery.event;
+
+import org.briarproject.bramble.api.event.Event;
+
+/**
+ * An event that is broadcast when the device starts or stops charging.
+ */
+public class BatteryEvent extends Event {
+
+	private final boolean charging;
+
+	public BatteryEvent(boolean charging) {
+		this.charging = charging;
+	}
+
+	public boolean isCharging() {
+		return charging;
+	}
+}

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

@@ -1,7 +1,6 @@
-package org.briarproject.briar.client;
+package org.briarproject.bramble.api.client;
 
 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.MetadataParser;
@@ -12,7 +11,7 @@ import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.InvalidMessageException;
 import org.briarproject.bramble.api.sync.Message;
-import org.briarproject.bramble.api.sync.ValidationManager.IncomingMessageHook;
+import org.briarproject.bramble.api.sync.validation.IncomingMessageHook;
 
 import javax.annotation.concurrent.Immutable;
 
@@ -62,5 +61,4 @@ public abstract class BdfIncomingMessageHook implements IncomingMessageHook {
 			throw new InvalidMessageException(e);
 		}
 	}
-
 }

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

@@ -9,7 +9,7 @@ import org.briarproject.bramble.api.sync.Group;
 import org.briarproject.bramble.api.sync.InvalidMessageException;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageContext;
-import org.briarproject.bramble.api.sync.ValidationManager.MessageValidator;
+import org.briarproject.bramble.api.sync.validation.MessageValidator;
 import org.briarproject.bramble.api.system.Clock;
 
 import java.util.logging.Logger;
@@ -48,12 +48,8 @@ public abstract class BdfMessageValidator implements MessageValidator {
 			throw new InvalidMessageException(
 					"Timestamp is too far in the future");
 		}
-		byte[] body = m.getBody();
-		if (body.length == 0) {
-			throw new InvalidMessageException("Message is too short");
-		}
 		try {
-			BdfList bodyList = clientHelper.toList(body);
+			BdfList bodyList = clientHelper.toList(m.getBody());
 			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/contact/Contact.java

@@ -4,8 +4,12 @@ import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
+import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
+import static org.briarproject.bramble.util.StringUtils.toUtf8;
+
 @Immutable
 @NotNullByDefault
 public class Contact {
@@ -13,13 +17,21 @@ public class Contact {
 	private final ContactId id;
 	private final Author author;
 	private final AuthorId localAuthorId;
+	@Nullable
+	private final String alias;
 	private final boolean verified, active;
 
 	public Contact(ContactId id, Author author, AuthorId localAuthorId,
-			boolean verified, boolean active) {
+			@Nullable String alias, boolean verified, boolean active) {
+		if (alias != null) {
+			int aliasLength = toUtf8(alias).length;
+			if (aliasLength == 0 || aliasLength > MAX_AUTHOR_NAME_LENGTH)
+				throw new IllegalArgumentException();
+		}
 		this.id = id;
 		this.author = author;
 		this.localAuthorId = localAuthorId;
+		this.alias = alias;
 		this.verified = verified;
 		this.active = active;
 	}
@@ -36,6 +48,11 @@ public class Contact {
 		return localAuthorId;
 	}
 
+	@Nullable
+	public String getAlias() {
+		return alias;
+	}
+
 	public boolean isVerified() {
 		return verified;
 	}

bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeListener.java

@@ -1,20 +0,0 @@
-package org.briarproject.bramble.api.contact;
-
-import org.briarproject.bramble.api.identity.Author;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-
-@NotNullByDefault
-public interface ContactExchangeListener {
-
-	void contactExchangeSucceeded(Author remoteAuthor);
-
-	/**
-	 * The exchange failed because the contact already exists.
-	 */
-	void duplicateContact(Author remoteAuthor);
-
-	/**
-	 * A general failure.
-	 */
-	void contactExchangeFailed();
-}

bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeTask.java

@@ -41,8 +41,7 @@ public interface ContactExchangeTask {
 	/**
 	 * Exchanges contact information with a remote peer.
 	 */
-	void startExchange(ContactExchangeListener listener,
-			LocalAuthor localAuthor, SecretKey masterSecret,
+	void startExchange(LocalAuthor localAuthor, SecretKey masterSecret,
 			DuplexTransportConnection conn, TransportId transportId,
 			boolean alice);
 }

bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactManager.java

@@ -5,11 +5,16 @@ import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
+import org.briarproject.bramble.api.identity.AuthorInfo;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 
 import java.util.Collection;
 
+import javax.annotation.Nullable;
+
+import static org.briarproject.bramble.api.contact.PendingContact.PendingContactState.FAILED;
+
 @NotNullByDefault
 public interface ContactManager {
 
@@ -49,6 +54,35 @@ public interface ContactManager {
 			long timestamp, boolean alice, boolean verified, boolean active)
 			throws DbException;
 
+	/**
+	 * Returns the static link that needs to be sent to the contact to be added.
+	 */
+	String getRemoteContactLink();
+
+	/**
+	 * Returns true if the given link is syntactically valid.
+	 */
+	boolean isValidRemoteContactLink(String link);
+
+	/**
+	 * Requests a new contact to be added via the given {@code link}.
+	 *
+	 * @param link The link received from the contact we want to add.
+	 * @param alias The alias the user has given this contact.
+	 * @return A PendingContact representing the contact to be added.
+	 */
+	PendingContact addRemoteContactRequest(String link, String alias);
+
+	/**
+	 * Returns a list of {@link PendingContact}s.
+	 */
+	Collection<PendingContact> getPendingContacts();
+
+	/**
+	 * Removes a {@link PendingContact} that is in state {@link FAILED}.
+	 */
+	void removePendingContact(PendingContact pendingContact);
+
 	/**
 	 * Returns the contact with the given ID.
 	 */
@@ -93,6 +127,18 @@ public interface ContactManager {
 	void setContactActive(Transaction txn, ContactId c, boolean active)
 			throws DbException;
 
+	/**
+	 * Sets an alias name for the contact or unsets it if alias is null.
+	 */
+	void setContactAlias(Transaction txn, ContactId c, @Nullable String alias)
+			throws DbException;
+
+	/**
+	 * Sets an alias name for the contact or unsets it if alias is null.
+	 */
+	void setContactAlias(ContactId c, @Nullable String alias)
+			throws DbException;
+
 	/**
 	 * Return true if a contact with this name and public key already exists
 	 */
@@ -105,6 +151,16 @@ public interface ContactManager {
 	boolean contactExists(AuthorId remoteAuthorId, AuthorId localAuthorId)
 			throws DbException;
 
+	/**
+	 * Returns the {@link AuthorInfo} for the given author.
+	 */
+	AuthorInfo getAuthorInfo(AuthorId a) throws DbException;
+
+	/**
+	 * Returns the {@link AuthorInfo} for the given author.
+	 */
+	AuthorInfo getAuthorInfo(Transaction txn, AuthorId a) throws DbException;
+
 	interface ContactHook {
 
 		void addingContact(Transaction txn, Contact c) throws DbException;

bramble-api/src/main/java/org/briarproject/bramble/api/contact/PendingContact.java

@@ -0,0 +1,54 @@
+package org.briarproject.bramble.api.contact;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+
+@Immutable
+@NotNullByDefault
+public class PendingContact {
+
+	public enum PendingContactState {
+		WAITING_FOR_CONNECTION,
+		CONNECTED,
+		ADDING_CONTACT,
+		FAILED
+	}
+
+	private final PendingContactId id;
+	private final String alias;
+	private final PendingContactState state;
+	private final long timestamp;
+
+	public PendingContact(PendingContactId id, String alias,
+			PendingContactState state, long timestamp) {
+		this.id = id;
+		this.alias = alias;
+		this.state = state;
+		this.timestamp = timestamp;
+	}
+
+	public String getAlias() {
+		return alias;
+	}
+
+	public PendingContactState getState() {
+		return state;
+	}
+
+	public long getTimestamp() {
+		return timestamp;
+	}
+
+	@Override
+	public int hashCode() {
+		return id.hashCode();
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		return o instanceof PendingContact &&
+				id.equals(((PendingContact) o).id);
+	}
+
+}

bramble-api/src/main/java/org/briarproject/bramble/api/contact/PendingContactId.java

@@ -0,0 +1,11 @@
+package org.briarproject.bramble.api.contact;
+
+import org.briarproject.bramble.api.UniqueId;
+
+public class PendingContactId extends UniqueId {
+
+	public PendingContactId(byte[] id) {
+		super(id);
+	}
+
+}

bramble-api/src/main/java/org/briarproject/bramble/api/contact/event/ContactExchangeFailedEvent.java

@@ -0,0 +1,32 @@
+package org.briarproject.bramble.api.contact.event;
+
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.identity.Author;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.Nullable;
+
+@NotNullByDefault
+public class ContactExchangeFailedEvent extends Event {
+
+	@Nullable
+	private final Author duplicateRemoteAuthor;
+
+	public ContactExchangeFailedEvent(@Nullable Author duplicateRemoteAuthor) {
+		this.duplicateRemoteAuthor = duplicateRemoteAuthor;
+	}
+
+	public ContactExchangeFailedEvent() {
+		this(null);
+	}
+
+	@Nullable
+	public Author getDuplicateRemoteAuthor() {
+		return duplicateRemoteAuthor;
+	}
+
+	public boolean wasDuplicateContact() {
+		return duplicateRemoteAuthor != null;
+	}
+
+}

bramble-api/src/main/java/org/briarproject/bramble/api/contact/event/ContactExchangeSucceededEvent.java

@@ -0,0 +1,20 @@
+package org.briarproject.bramble.api.contact.event;
+
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.identity.Author;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public class ContactExchangeSucceededEvent extends Event {
+
+	private final Author remoteAuthor;
+
+	public ContactExchangeSucceededEvent(Author remoteAuthor) {
+		this.remoteAuthor = remoteAuthor;
+	}
+
+	public Author getRemoteAuthor() {
+		return remoteAuthor;
+	}
+
+}

bramble-api/src/main/java/org/briarproject/bramble/api/contact/event/PendingContactStateChangedEvent.java

@@ -0,0 +1,34 @@
+package org.briarproject.bramble.api.contact.event;
+
+import org.briarproject.bramble.api.contact.PendingContact.PendingContactState;
+import org.briarproject.bramble.api.contact.PendingContactId;
+import org.briarproject.bramble.api.event.Event;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.concurrent.Immutable;
+
+/**
+ * An event that is broadcast when a pending contact's state is changed.
+ */
+@Immutable
+@NotNullByDefault
+public class PendingContactStateChangedEvent extends Event {
+
+	private final PendingContactId id;
+	private final PendingContactState state;
+
+	public PendingContactStateChangedEvent(PendingContactId id,
+			PendingContactState state) {
+		this.id = id;
+		this.state = state;
+	}
+
+	public PendingContactId getId() {
+		return id;
+	}
+
+	public PendingContactState getPendingContactState() {
+		return state;
+	}
+
+}

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

@@ -0,0 +1,71 @@
+package org.briarproject.bramble.api.data;
+
+import org.briarproject.bramble.api.Bytes;
+import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import javax.annotation.Nullable;
+
+import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
+import static org.briarproject.bramble.util.StringUtils.toHexString;
+
+@NotNullByDefault
+public class BdfStringUtils {
+
+	public static String toString(@Nullable Object o) throws FormatException {
+		return toString(o, 0);
+	}
+
+	private static String toString(@Nullable Object o, int indent)
+			throws FormatException {
+		if (o == null || o == NULL_VALUE) return "null";
+		if (o instanceof Boolean) return o.toString();
+		if (o instanceof Number) return o.toString();
+		if (o instanceof String) return "\"" + o + "\"";
+		if (o instanceof Bytes)
+			return "x" + toHexString(((Bytes) o).getBytes());
+		if (o instanceof byte[])
+			return "x" + toHexString((byte[]) o);
+		if (o instanceof List) {
+			List<?> list = (List) o;
+			StringBuilder sb = new StringBuilder();
+			sb.append("[\n");
+			int i = 0, size = list.size();
+			for (Object e : list) {
+				indent(sb, indent + 1);
+				sb.append(toString(e, indent + 1));
+				if (i++ < size - 1) sb.append(',');
+				sb.append('\n');
+			}
+			indent(sb, indent);
+			sb.append(']');
+			return sb.toString();
+		}
+		if (o instanceof Map) {
+			Map<?, ?> map = (Map) o;
+			StringBuilder sb = new StringBuilder();
+			sb.append("{\n");
+			int i = 0, size = map.size();
+			for (Entry e : map.entrySet()) {
+				indent(sb, indent + 1);
+				sb.append(toString(e.getKey(), indent + 1));
+				sb.append(": ");
+				sb.append(toString(e.getValue(), indent + 1));
+				if (i++ < size - 1) sb.append(',');
+				sb.append('\n');
+			}
+			indent(sb, indent);
+			sb.append('}');
+			return sb.toString();
+		}
+		throw new FormatException();
+	}
+
+	private static void indent(StringBuilder sb, int indent) {
+		for (int i = 0; i < indent; i++) sb.append('\t');
+	}
+}

bramble-api/src/main/java/org/briarproject/bramble/api/db/DatabaseComponent.java

@@ -19,6 +19,7 @@ import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.sync.MessageStatus;
 import org.briarproject.bramble.api.sync.Offer;
 import org.briarproject.bramble.api.sync.Request;
+import org.briarproject.bramble.api.sync.validation.MessageState;
 import org.briarproject.bramble.api.transport.KeySet;
 import org.briarproject.bramble.api.transport.KeySetId;
 import org.briarproject.bramble.api.transport.TransportKeys;
@@ -28,8 +29,6 @@ import java.util.Map;
 
 import javax.annotation.Nullable;
 
-import static org.briarproject.bramble.api.sync.ValidationManager.State;
-
 /**
  * Encapsulates the database implementation and exposes high-level operations
  * to other components.
@@ -76,6 +75,27 @@ public interface DatabaseComponent {
 	 */
 	void endTransaction(Transaction txn);
 
+	/**
+	 * Runs the given task within a transaction.
+	 */
+	<E extends Exception> void transaction(boolean readOnly,
+			DbRunnable<E> task) throws DbException, E;
+
+	/**
+	 * Runs the given task within a transaction and returns the result of the
+	 * task.
+	 */
+	<R, E extends Exception> R transactionWithResult(boolean readOnly,
+			DbCallable<R, E> task) throws DbException, E;
+
+	/**
+	 * Runs the given task within a transaction and returns the result of the
+	 * task, which may be null.
+	 */
+	@Nullable
+	<R, E extends Exception> R transactionWithNullableResult(boolean readOnly,
+			NullableDbCallable<R, E> task) throws DbException, E;
+
 	/**
 	 * Stores a contact associated with the given local and remote pseudonyms,
 	 * and returns an ID for the contact.
@@ -353,12 +373,12 @@ public interface DatabaseComponent {
 	/**
 	 * Returns the IDs and states of all dependencies of the given message.
 	 * For missing dependencies and dependencies in other groups, the state
-	 * {@link State UNKNOWN} is returned.
+	 * {@link MessageState UNKNOWN} is returned.
 	 * <p/>
 	 * Read-only.
 	 */
-	Map<MessageId, State> getMessageDependencies(Transaction txn, MessageId m)
-			throws DbException;
+	Map<MessageId, MessageState> getMessageDependencies(Transaction txn,
+			MessageId m) throws DbException;
 
 	/**
 	 * Returns the IDs and states of all dependents of the given message.
@@ -367,15 +387,16 @@ public interface DatabaseComponent {
 	 * <p/>
 	 * Read-only.
 	 */
-	Map<MessageId, State> getMessageDependents(Transaction txn, MessageId m)
-			throws DbException;
+	Map<MessageId, MessageState> getMessageDependents(Transaction txn,
+			MessageId m) throws DbException;
 
 	/**
 	 * Gets the validation and delivery state of the given message.
 	 * <p/>
 	 * Read-only.
 	 */
-	State getMessageState(Transaction txn, MessageId m) throws DbException;
+	MessageState getMessageState(Transaction txn, MessageId m)
+			throws DbException;
 
 	/**
 	 * Returns the status of the given delivered message with respect to the
@@ -502,6 +523,12 @@ public interface DatabaseComponent {
 	void setContactActive(Transaction txn, ContactId c, boolean active)
 			throws DbException;
 
+	/**
+	 * Sets an alias name for the contact or unsets it if alias is null.
+	 */
+	void setContactAlias(Transaction txn, ContactId c, @Nullable String alias)
+			throws DbException;
+
 	/**
 	 * Sets the given group's visibility to the given contact.
 	 */
@@ -516,7 +543,7 @@ public interface DatabaseComponent {
 	/**
 	 * Sets the validation and delivery state of the given message.
 	 */
-	void setMessageState(Transaction txn, MessageId m, State state)
+	void setMessageState(Transaction txn, MessageId m, MessageState state)
 			throws DbException;
 
 	/**

bramble-api/src/main/java/org/briarproject/bramble/api/db/DbCallable.java

@@ -0,0 +1,9 @@
+package org.briarproject.bramble.api.db;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface DbCallable<R, E extends Exception> {
+
+	R call(Transaction txn) throws DbException, E;
+}

bramble-api/src/main/java/org/briarproject/bramble/api/db/DbRunnable.java

@@ -0,0 +1,9 @@
+package org.briarproject.bramble.api.db;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+@NotNullByDefault
+public interface DbRunnable<E extends Exception> {
+
+	void run(Transaction txn) throws DbException, E;
+}

bramble-api/src/main/java/org/briarproject/bramble/api/db/MigrationListener.java

@@ -6,6 +6,10 @@ public interface MigrationListener {
 	 * This is called when a migration is started while opening the database.
 	 * It will be called once for each migration being applied.
 	 */
-	void onMigrationRun();
+	void onDatabaseMigration();
 
+	/**
+	 * This is called when compaction is started while opening the database.
+	 */
+	void onDatabaseCompaction();
 }

bramble-api/src/main/java/org/briarproject/bramble/api/db/NullableDbCallable.java

@@ -0,0 +1,12 @@
+package org.briarproject.bramble.api.db;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.Nullable;
+
+@NotNullByDefault
+public interface NullableDbCallable<R, E extends Exception> {
+
+	@Nullable
+	R call(Transaction txn) throws DbException, E;
+}

bramble-api/src/main/java/org/briarproject/bramble/api/identity/Author.java

@@ -16,10 +16,6 @@ import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_PUBLIC_K
 @NotNullByDefault
 public class Author implements Nameable {
 
-	public enum Status {
-		NONE, ANONYMOUS, UNKNOWN, UNVERIFIED, VERIFIED, OURSELVES
-	}
-
 	/**
 	 * The current version of the author structure.
 	 */

bramble-api/src/main/java/org/briarproject/bramble/api/identity/AuthorInfo.java

@@ -0,0 +1,56 @@
+package org.briarproject.bramble.api.identity;
+
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.Immutable;
+
+@Immutable
+@NotNullByDefault
+public class AuthorInfo {
+
+	public enum Status {
+		NONE, ANONYMOUS, UNKNOWN, UNVERIFIED, VERIFIED, OURSELVES;
+
+		public boolean isContact() {
+			return this == UNVERIFIED || this == VERIFIED;
+		}
+	}
+
+	private final Status status;
+	@Nullable
+	private final String alias;
+
+	public AuthorInfo(Status status, @Nullable String alias) {
+		this.status = status;
+		this.alias = alias;
+	}
+
+	public AuthorInfo(Status status) {
+		this(status, null);
+	}
+
+	public Status getStatus() {
+		return status;
+	}
+
+	@Nullable
+	public String getAlias() {
+		return alias;
+	}
+
+	@Override
+	public int hashCode() {
+		int hashCode = status.ordinal();
+		if (alias != null) hashCode += alias.hashCode();
+		return hashCode;
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (!(o instanceof AuthorInfo)) return false;
+		AuthorInfo info = (AuthorInfo) o;
+		return status == info.status &&
+				(alias == null ? info.alias == null : alias.equals(info.alias));
+	}
+}

bramble-api/src/main/java/org/briarproject/bramble/api/identity/IdentityManager.java

@@ -3,7 +3,6 @@ package org.briarproject.bramble.api.identity;
 import org.briarproject.bramble.api.crypto.CryptoExecutor;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
-import org.briarproject.bramble.api.identity.Author.Status;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 
 @NotNullByDefault
@@ -37,14 +36,4 @@ public interface IdentityManager {
 	 */
 	LocalAuthor getLocalAuthor(Transaction txn) throws DbException;
 
-	/**
-	 * Returns the {@link Status} of the given author.
-	 */
-	Status getAuthorStatus(AuthorId a) throws DbException;
-
-	/**
-	 * Returns the {@link Status} of the given author.
-	 */
-	Status getAuthorStatus(Transaction txn, AuthorId a) throws DbException;
-
 }

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

@@ -21,7 +21,7 @@ public interface KeyAgreementConstants {
 	/**
 	 * The connection timeout in milliseconds.
 	 */
-	long CONNECTION_TIMEOUT = 20 * 1000;
+	long CONNECTION_TIMEOUT = 60_000;
 
 	/**
 	 * The transport identifier for Bluetooth.

bramble-api/src/main/java/org/briarproject/bramble/api/lifecycle/LifecycleManager.java

@@ -34,7 +34,8 @@ public interface LifecycleManager {
 	 */
 	enum LifecycleState {
 
-		STARTING, MIGRATING_DATABASE, STARTING_SERVICES, RUNNING, STOPPING;
+		STARTING, MIGRATING_DATABASE, COMPACTING_DATABASE, STARTING_SERVICES,
+		RUNNING, STOPPING;
 
 		public boolean isAfter(LifecycleState state) {
 			return ordinal() > state.ordinal();

bramble-api/src/main/java/org/briarproject/bramble/api/nullsafety/NullSafety.java

@@ -0,0 +1,15 @@
+package org.briarproject.bramble.api.nullsafety;
+
+import javax.annotation.Nullable;
+
+@NotNullByDefault
+public class NullSafety {
+
+	/**
+	 * Stand-in for `Objects.requireNonNull()`.
+	 */
+	public static <T> T requireNonNull(@Nullable T t) {
+		if (t == null) throw new NullPointerException();
+		return t;
+	}
+}

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

@@ -4,7 +4,8 @@ public interface TorConstants {
 
 	TransportId ID = new TransportId("org.briarproject.bramble.tor");
 
-	String PROP_ONION = "onion";
+	String PROP_ONION_V2 = "onion";
+	String PROP_ONION_V3 = "onion3";
 
 	int SOCKS_PORT = 59050;
 	int CONTROL_PORT = 59051;
@@ -15,6 +16,7 @@ public interface TorConstants {
 	String PREF_TOR_NETWORK = "network2";
 	String PREF_TOR_PORT = "port";
 	String PREF_TOR_MOBILE = "useMobileData";
+	String PREF_TOR_ONLY_WHEN_CHARGING = "onlyWhenCharging";
 
 	int PREF_TOR_NETWORK_AUTOMATIC = 0;
 	int PREF_TOR_NETWORK_WITHOUT_BRIDGES = 1;

bramble-api/src/main/java/org/briarproject/bramble/api/sync/Message.java

@@ -16,6 +16,7 @@ public class Message {
 	private final byte[] body;
 
 	public Message(MessageId id, GroupId groupId, long timestamp, byte[] body) {
+		if (body.length == 0) throw new IllegalArgumentException();
 		if (body.length > MAX_MESSAGE_BODY_LENGTH)
 			throw new IllegalArgumentException();
 		this.id = id;

bramble-api/src/main/java/org/briarproject/bramble/api/sync/ValidationManager.java

@@ -1,87 +0,0 @@
-package org.briarproject.bramble.api.sync;
-
-import org.briarproject.bramble.api.crypto.SecretKey;
-import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.db.Metadata;
-import org.briarproject.bramble.api.db.Transaction;
-import org.briarproject.bramble.api.lifecycle.LifecycleManager;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-
-/**
- * Responsible for managing message validators and passing them messages to
- * validate.
- */
-@NotNullByDefault
-public interface ValidationManager {
-
-	enum State {
-
-		UNKNOWN(0), INVALID(1), PENDING(2), DELIVERED(3);
-
-		private final int value;
-
-		State(int value) {
-			this.value = value;
-		}
-
-		public int getValue() {
-			return value;
-		}
-
-		public static State fromValue(int value) {
-			for (State s : values()) if (s.value == value) return s;
-			throw new IllegalArgumentException();
-		}
-	}
-
-	/**
-	 * Registers the message validator for the given client. This method
-	 * should be called before
-	 * {@link LifecycleManager#startServices(SecretKey)}.
-	 */
-	void registerMessageValidator(ClientId c, int majorVersion,
-			MessageValidator v);
-
-	/**
-	 * Registers the incoming message hook for the given client. The hook will
-	 * be called once for each incoming message that passes validation. This
-	 * method should be called before
-	 * {@link LifecycleManager#startServices(SecretKey)}.
-	 */
-	void registerIncomingMessageHook(ClientId c, int majorVersion,
-			IncomingMessageHook hook);
-
-	interface MessageValidator {
-
-		/**
-		 * Validates the given message and returns its metadata and
-		 * dependencies.
-		 */
-		MessageContext validateMessage(Message m, Group g)
-				throws InvalidMessageException;
-	}
-
-	interface IncomingMessageHook {
-
-		/**
-		 * Called once for each incoming message that passes validation.
-		 *
-		 * @return whether or not this message should be shared
-		 * @throws DbException Should only be used for real database errors.
-		 * If this is thrown, delivery will be attempted again at next startup,
-		 * whereas if an InvalidMessageException is thrown,
-		 * the message will be permanently invalidated.
-		 * @throws InvalidMessageException for any non-database error
-		 * that occurs while handling remotely created data.
-		 * This includes errors that occur while handling locally created data
-		 * in a context controlled by remotely created data
-		 * (for example, parsing the metadata of a dependency
-		 * of an incoming message).
-		 * Throwing this will delete the incoming message and its metadata
-		 * marking it as invalid in the database.
-		 * Never rethrow DbException as InvalidMessageException!
-		 */
-		boolean incomingMessage(Transaction txn, Message m, Metadata meta)
-				throws DbException, InvalidMessageException;
-	}
-}

bramble-api/src/main/java/org/briarproject/bramble/api/sync/event/MessageStateChangedEvent.java

@@ -3,11 +3,10 @@ package org.briarproject.bramble.api.sync.event;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.MessageId;
+import org.briarproject.bramble.api.sync.validation.MessageState;
 
 import javax.annotation.concurrent.Immutable;
 
-import static org.briarproject.bramble.api.sync.ValidationManager.State;
-
 /**
  * An event that is broadcast when a message state changed.
  */
@@ -17,10 +16,10 @@ public class MessageStateChangedEvent extends Event {
 
 	private final MessageId messageId;
 	private final boolean local;
-	private final State state;
+	private final MessageState state;
 
 	public MessageStateChangedEvent(MessageId messageId, boolean local,
-			State state) {
+			MessageState state) {
 		this.messageId = messageId;
 		this.local = local;
 		this.state = state;
@@ -34,7 +33,7 @@ public class MessageStateChangedEvent extends Event {
 		return local;
 	}
 
-	public State getState() {
+	public MessageState getState() {
 		return state;
 	}
 

bramble-api/src/main/java/org/briarproject/bramble/api/sync/validation/IncomingMessageHook.java

@@ -0,0 +1,31 @@
+package org.briarproject.bramble.api.sync.validation;
+
+import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.Metadata;
+import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.sync.InvalidMessageException;
+import org.briarproject.bramble.api.sync.Message;
+
+public interface IncomingMessageHook {
+
+	/**
+	 * Called once for each incoming message that passes validation.
+	 *
+	 * @return whether or not this message should be shared
+	 * @throws DbException Should only be used for real database errors.
+	 * If this is thrown, delivery will be attempted again at next startup,
+	 * whereas if an InvalidMessageException is thrown,
+	 * the message will be permanently invalidated.
+	 * @throws InvalidMessageException for any non-database error
+	 * that occurs while handling remotely created data.
+	 * This includes errors that occur while handling locally created data
+	 * in a context controlled by remotely created data
+	 * (for example, parsing the metadata of a dependency
+	 * of an incoming message).
+	 * Throwing this will delete the incoming message and its metadata
+	 * marking it as invalid in the database.
+	 * Never rethrow DbException as InvalidMessageException!
+	 */
+	boolean incomingMessage(Transaction txn, Message m, Metadata meta)
+			throws DbException, InvalidMessageException;
+}

bramble-api/src/main/java/org/briarproject/bramble/api/sync/validation/MessageState.java

@@ -0,0 +1,21 @@
+package org.briarproject.bramble.api.sync.validation;
+
+public enum MessageState {
+
+	UNKNOWN(0), INVALID(1), PENDING(2), DELIVERED(3);
+
+	private final int value;
+
+	MessageState(int value) {
+		this.value = value;
+	}
+
+	public int getValue() {
+		return value;
+	}
+
+	public static MessageState fromValue(int value) {
+		for (MessageState s : values()) if (s.value == value) return s;
+		throw new IllegalArgumentException();
+	}
+}

bramble-api/src/main/java/org/briarproject/bramble/api/sync/validation/MessageValidator.java

@@ -0,0 +1,16 @@
+package org.briarproject.bramble.api.sync.validation;
+
+import org.briarproject.bramble.api.sync.Group;
+import org.briarproject.bramble.api.sync.InvalidMessageException;
+import org.briarproject.bramble.api.sync.Message;
+import org.briarproject.bramble.api.sync.MessageContext;
+
+public interface MessageValidator {
+
+	/**
+	 * Validates the given message and returns its metadata and
+	 * dependencies.
+	 */
+	MessageContext validateMessage(Message m, Group g)
+			throws InvalidMessageException;
+}

bramble-api/src/main/java/org/briarproject/bramble/api/sync/validation/ValidationManager.java

@@ -0,0 +1,31 @@
+package org.briarproject.bramble.api.sync.validation;
+
+import org.briarproject.bramble.api.crypto.SecretKey;
+import org.briarproject.bramble.api.lifecycle.LifecycleManager;
+import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
+import org.briarproject.bramble.api.sync.ClientId;
+
+/**
+ * Responsible for managing message validators and passing them messages to
+ * validate.
+ */
+@NotNullByDefault
+public interface ValidationManager {
+
+	/**
+	 * Registers the {@link MessageValidator} for the given client. This method
+	 * should be called before
+	 * {@link LifecycleManager#startServices(SecretKey)}.
+	 */
+	void registerMessageValidator(ClientId c, int majorVersion,
+			MessageValidator v);
+
+	/**
+	 * Registers the {@link IncomingMessageHook} for the given client. The hook
+	 * will be called once for each incoming message that passes validation.
+	 * This method should be called before
+	 * {@link LifecycleManager#startServices(SecretKey)}.
+	 */
+	void registerIncomingMessageHook(ClientId c, int majorVersion,
+			IncomingMessageHook hook);
+}

bramble-api/src/main/java/org/briarproject/bramble/api/versioning/ClientVersioningManager.java

@@ -38,6 +38,13 @@ public interface ClientVersioningManager {
 	Visibility getClientVisibility(Transaction txn, ContactId contactId,
 			ClientId clientId, int majorVersion) throws DbException;
 
+	/**
+	 * Returns the minor version of the given client that is supported by the
+	 * given contact, or -1 if the contact does not support the client.
+	 */
+	int getClientMinorVersion(Transaction txn, ContactId contactId,
+			ClientId clientId, int majorVersion) throws DbException;
+
 	interface ClientVersioningHook {
 
 		void onClientVisibilityChanging(Transaction txn, Contact c,

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

@@ -8,12 +8,15 @@ import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.net.ServerSocket;
 import java.net.Socket;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
 
 import static java.util.logging.Level.WARNING;
+import static org.briarproject.bramble.util.LogUtils.logException;
 
 @NotNullByDefault
 public class IoUtils {
@@ -54,16 +57,35 @@ public class IoUtils {
 			out.flush();
 			out.close();
 		} catch (IOException e) {
-			tryToClose(in);
-			tryToClose(out);
+			tryToClose(in, LOG, WARNING);
+			tryToClose(out, LOG, WARNING);
 		}
 	}
 
-	private static void tryToClose(@Nullable Closeable c) {
+	public static void tryToClose(@Nullable Closeable c, Logger logger,
+			Level level) {
 		try {
 			if (c != null) c.close();
 		} catch (IOException e) {
-			// We did our best
+			logException(logger, level, e);
+		}
+	}
+
+	public static void tryToClose(@Nullable Socket s, Logger logger,
+			Level level) {
+		try {
+			if (s != null) s.close();
+		} catch (IOException e) {
+			logException(logger, level, e);
+		}
+	}
+
+	public static void tryToClose(@Nullable ServerSocket ss, Logger logger,
+			Level level) {
+		try {
+			if (ss != null) ss.close();
+		} catch (IOException e) {
+			logException(logger, level, e);
 		}
 	}
 

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

@@ -10,8 +10,6 @@ public class OsUtils {
 	@Nullable
 	private static final String os = System.getProperty("os.name");
 	@Nullable
-	private static final String version = System.getProperty("os.version");
-	@Nullable
 	private static final String vendor = System.getProperty("java.vendor");
 
 	public static boolean isWindows() {

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

@@ -47,7 +47,7 @@ public class StringUtils {
 		try {
 			return s.getBytes("UTF-8");
 		} catch (UnsupportedEncodingException e) {
-			throw new RuntimeException(e);
+			throw new AssertionError(e);
 		}
 	}
 
@@ -63,7 +63,7 @@ public class StringUtils {
 		try {
 			return decoder.decode(buffer).toString();
 		} catch (CharacterCodingException e) {
-			throw new RuntimeException(e);
+			throw new AssertionError(e);
 		}
 	}
 

bramble-api/src/test/java/org/briarproject/bramble/api/identity/AuthorInfoTest.java

@@ -0,0 +1,42 @@
+package org.briarproject.bramble.api.identity;
+
+import org.briarproject.bramble.test.BrambleTestCase;
+import org.junit.Test;
+
+import static org.briarproject.bramble.api.identity.AuthorInfo.Status.NONE;
+import static org.briarproject.bramble.api.identity.AuthorInfo.Status.VERIFIED;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+
+public class AuthorInfoTest extends BrambleTestCase {
+
+	@Test
+	public void testEquals() {
+		assertEquals(
+				new AuthorInfo(NONE),
+				new AuthorInfo(NONE, null)
+		);
+		assertEquals(
+				new AuthorInfo(NONE, "test"),
+				new AuthorInfo(NONE, "test")
+		);
+
+		assertNotEquals(
+				new AuthorInfo(NONE),
+				new AuthorInfo(VERIFIED)
+		);
+		assertNotEquals(
+				new AuthorInfo(NONE, "test"),
+				new AuthorInfo(NONE)
+		);
+		assertNotEquals(
+				new AuthorInfo(NONE),
+				new AuthorInfo(NONE, "test")
+		);
+		assertNotEquals(
+				new AuthorInfo(NONE, "a"),
+				new AuthorInfo(NONE, "b")
+		);
+	}
+
+}

bramble-api/src/test/java/org/briarproject/bramble/test/SettableClock.java

@@ -0,0 +1,24 @@
+package org.briarproject.bramble.test;
+
+import org.briarproject.bramble.api.system.Clock;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+public class SettableClock implements Clock {
+
+	private final AtomicLong time;
+
+	public SettableClock(AtomicLong time) {
+		this.time = time;
+	}
+
+	@Override
+	public long currentTimeMillis() {
+		return time.get();
+	}
+
+	@Override
+	public void sleep(long milliseconds) throws InterruptedException {
+		Thread.sleep(milliseconds);
+	}
+}

bramble-api/witness.gradle

@@ -2,7 +2,7 @@ dependencyVerification {
     verify = [
         'cglib:cglib:3.2.0:cglib-3.2.0.jar:adb13bab79712ad6bdf1bd59f2a3918018a8016e722e8a357065afb9e6690861',
         'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
-        'com.google.dagger:dagger:2.0.2:dagger-2.0.2.jar:84c0282ed8be73a29e0475d639da030b55dee72369e58dd35ae7d4fe6243dcf9',
+        'com.google.dagger:dagger:2.19:dagger-2.19.jar:514b6f1e0727c6572e1d65cb27e4ae668b7aeaeb93a29515182965265b609939',
         'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
         'junit:junit:4.12:junit-4.12.jar:59721f0805e223d84b90677887d9ff567dc534d7c502ca903c0c2b17f05c116a',
         'org.apache.ant:ant-launcher:1.9.4:ant-launcher-1.9.4.jar:7bccea20b41801ca17bcbc909a78c835d0f443f12d639c77bd6ae3d05861608d',

bramble-core/build.gradle

@@ -3,10 +3,10 @@ sourceCompatibility = 1.8
 targetCompatibility = 1.8
 
 apply plugin: 'ru.vyarus.animalsniffer'
-apply plugin: 'net.ltgt.apt'
 apply plugin: 'idea'
 apply plugin: 'witness'
 apply from: 'witness.gradle'
+apply from: '../dagger.gradle'
 
 dependencies {
 	implementation project(path: ':bramble-api', configuration: 'default')
@@ -14,10 +14,9 @@ dependencies {
 	implementation 'com.h2database:h2:1.4.192' // The last version that supports Java 1.6
 	implementation 'org.bitlet:weupnp:0.1.4'
 	implementation 'net.i2p.crypto:eddsa:0.2.0'
-	implementation 'org.whispersystems:curve25519-java:0.4.1'
-	implementation 'org.briarproject:jtorctl:0.3'
+	implementation 'org.whispersystems:curve25519-java:0.5.0'
 
-	apt 'com.google.dagger:dagger-compiler:2.0.2'
+	annotationProcessor 'com.google.dagger:dagger-compiler:2.19'
 
 	testImplementation project(path: ':bramble-api', configuration: 'testOutput')
 	testImplementation 'org.hsqldb:hsqldb:2.3.5' // The last version that supports Java 1.6
@@ -25,10 +24,8 @@ dependencies {
 	testImplementation "org.jmock:jmock:2.8.2"
 	testImplementation "org.jmock:jmock-junit4:2.8.2"
 	testImplementation "org.jmock:jmock-legacy:2.8.2"
-	testImplementation "org.hamcrest:hamcrest-library:1.3"
-	testImplementation "org.hamcrest:hamcrest-core:1.3"
 
-	testApt 'com.google.dagger:dagger-compiler:2.0.2'
+	testAnnotationProcessor 'com.google.dagger:dagger-compiler:2.19'
 
 	signature 'org.codehaus.mojo.signature:java16:1.1@signature'
 }

bramble-core/src/main/java/net/freehaven/tor/control/.cvsignore

@@ -0,0 +1 @@
+*.class

bramble-core/src/main/java/net/freehaven/tor/control/Bytes.java

@@ -0,0 +1,114 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Static class to do bytewise structure manipulation in Java.
+ */
+/* XXXX There must be a better way to do most of this.
+ * XXXX The string logic here uses default encoding, which is stupid.
+ */
+final class Bytes {
+
+    /** Write the two-byte value in 's' into the byte array 'ba', starting at
+     * the index 'pos'. */
+    public static void setU16(byte[] ba, int pos, short s) {
+        ba[pos]   = (byte)((s >> 8) & 0xff);
+        ba[pos+1] = (byte)((s     ) & 0xff);
+    }
+
+    /** Write the four-byte value in 'i' into the byte array 'ba', starting at
+     * the index 'pos'. */
+    public static void setU32(byte[] ba, int pos, int i) {
+        ba[pos]   = (byte)((i >> 24) & 0xff);
+        ba[pos+1] = (byte)((i >> 16) & 0xff);
+        ba[pos+2] = (byte)((i >>  8) & 0xff);
+        ba[pos+3] = (byte)((i      ) & 0xff);
+    }
+
+    /** Return the four-byte value starting at index 'pos' within 'ba' */
+    public static int getU32(byte[] ba, int pos) {
+        return
+            ((ba[pos  ]&0xff)<<24) |
+            ((ba[pos+1]&0xff)<<16) |
+            ((ba[pos+2]&0xff)<< 8)  |
+            ((ba[pos+3]&0xff));
+    }
+
+    public static String getU32S(byte[] ba, int pos) {
+        return String.valueOf( (getU32(ba,pos))&0xffffffffL );
+    }
+
+    /** Return the two-byte value starting at index 'pos' within 'ba' */
+    public static int getU16(byte[] ba, int pos) {
+        return
+            ((ba[pos  ]&0xff)<<8) |
+            ((ba[pos+1]&0xff));
+    }
+
+    /** Return the string starting at position 'pos' of ba and extending
+     * until a zero byte or the end of the string. */
+    public static String getNulTerminatedStr(byte[] ba, int pos) {
+        int len, maxlen = ba.length-pos;
+        for (len=0; len<maxlen; ++len) {
+            if (ba[pos+len] == 0)
+                break;
+        }
+        return new String(ba, pos, len);
+    }
+
+    /**
+     * Read bytes from 'ba' starting at 'pos', dividing them into strings
+     * along the character in 'split' and writing them into 'lst'
+     */
+    public static void splitStr(List<String> lst, byte[] ba, int pos, byte split) {
+        while (pos < ba.length && ba[pos] != 0) {
+            int len;
+            for (len=0; pos+len < ba.length; ++len) {
+                if (ba[pos+len] == 0 || ba[pos+len] == split)
+                    break;
+            }
+            if (len>0)
+                lst.add(new String(ba, pos, len));
+            pos += len;
+            if (ba[pos] == split)
+                ++pos;
+        }
+    }
+
+    /**
+     * Read bytes from 'ba' starting at 'pos', dividing them into strings
+     * along the character in 'split' and writing them into 'lst'
+     */
+    public static List<String> splitStr(List<String> lst, String str) {
+        // split string on spaces, include trailing/leading
+        String[] tokenArray = str.split(" ", -1);
+        if (lst == null) {
+            lst = Arrays.asList( tokenArray );
+        } else {
+            lst.addAll( Arrays.asList( tokenArray ) );
+        }
+        return lst;
+    }
+
+    private static final char[] NYBBLES = {
+        '0', '1', '2', '3', '4', '5', '6', '7',
+        '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
+    };
+
+    public static final String hex(byte[] ba) {
+        StringBuffer buf = new StringBuffer();
+        for (int i = 0; i < ba.length; ++i) {
+            int b = (ba[i]) & 0xff;
+            buf.append(NYBBLES[b >> 4]);
+            buf.append(NYBBLES[b&0x0f]);
+        }
+        return buf.toString();
+    }
+
+    private Bytes() {};
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/ConfigEntry.java

@@ -0,0 +1,20 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+/** A single key-value pair from Tor's configuration. */
+public class ConfigEntry {
+    public ConfigEntry(String k, String v) {
+        key = k;
+        value = v;
+        is_default = false;
+    }
+    public ConfigEntry(String k) {
+        key = k;
+        value = "";
+        is_default = true;
+    }
+    public final String key;
+    public final String value;
+    public final boolean is_default;
+}

bramble-core/src/main/java/net/freehaven/tor/control/EventHandler.java

@@ -0,0 +1,75 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+/**
+ * Abstract interface whose methods are invoked when Tor sends us an event.
+ *
+ * @see TorControlConnection#setEventHandler
+ * @see TorControlConnection#setEvents
+ */
+public interface EventHandler {
+    /**
+     * Invoked when a circuit's status has changed.
+     * Possible values for <b>status</b> are:
+     * <ul>
+     *   <li>"LAUNCHED" :  circuit ID assigned to new circuit</li>
+     *   <li>"BUILT"    :  all hops finished, can now accept streams</li>
+     *   <li>"EXTENDED" :  one more hop has been completed</li>
+     *   <li>"FAILED"   :  circuit closed (was not built)</li>
+     *   <li>"CLOSED"   :  circuit closed (was built)</li>
+     *	</ul>
+     * 
+     * <b>circID</b> is the alphanumeric identifier of the affected circuit,
+     * and <b>path</b> is a comma-separated list of alphanumeric ServerIDs.
+     */
+    public void circuitStatus(String status, String circID, String path);
+    /**
+     * Invoked when a stream's status has changed.
+     * Possible values for <b>status</b> are:
+     * <ul>
+     *   <li>"NEW"         :  New request to connect</li>
+     *   <li>"NEWRESOLVE"  :  New request to resolve an address</li>
+     *   <li>"SENTCONNECT" :  Sent a connect cell along a circuit</li>
+     *   <li>"SENTRESOLVE" :  Sent a resolve cell along a circuit</li>
+     *   <li>"SUCCEEDED"   :  Received a reply; stream established</li>
+     *   <li>"FAILED"      :  Stream failed and not retriable.</li>
+     *   <li>"CLOSED"      :  Stream closed</li>
+     *   <li>"DETACHED"    :  Detached from circuit; still retriable.</li>
+     *	</ul>
+     *
+     * <b>streamID</b> is the alphanumeric identifier of the affected stream,
+     * and its <b>target</b> is specified as address:port.
+     */
+    public void streamStatus(String status, String streamID, String target);
+    /**
+     * Invoked when the status of a connection to an OR has changed.
+     * Possible values for <b>status</b> are ["LAUNCHED" | "CONNECTED" | "FAILED" | "CLOSED"].
+     * <b>orName</b> is the alphanumeric identifier of the OR affected.
+     */
+    public void orConnStatus(String status, String orName);
+    /**
+     * Invoked once per second. <b>read</b> and <b>written</b> are
+     * the number of bytes read and written, respectively, in
+     * the last second.
+     */
+    public void bandwidthUsed(long read, long written);
+    /**
+     * Invoked whenever Tor learns about new ORs.  The <b>orList</b> object
+     * contains the alphanumeric ServerIDs associated with the new ORs.
+     */
+    public void newDescriptors(java.util.List<String> orList);
+    /**
+     * Invoked when Tor logs a message.
+     * <b>severity</b> is one of ["DEBUG" | "INFO" | "NOTICE" | "WARN" | "ERR"],
+     * and <b>msg</b> is the message string.
+     */
+    public void message(String severity, String msg);
+    /**
+     * Invoked when an unspecified message is received.
+     * <type> is the message type, and <msg> is the message string.
+     */
+    public void unrecognized(String type, String msg);
+
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/NullEventHandler.java

@@ -0,0 +1,18 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+/**
+ * Implementation of EventHandler that ignores all events.  Useful
+ * when you only want to override one method.
+ */
+public class NullEventHandler implements EventHandler {
+    public void circuitStatus(String status, String circID, String path) {}
+    public void streamStatus(String status, String streamID, String target) {}
+    public void orConnStatus(String status, String orName) {}
+    public void bandwidthUsed(long read, long written) {}
+    public void newDescriptors(java.util.List<String> orList) {}
+    public void message(String severity, String msg) {}
+    public void unrecognized(String type, String msg) {}
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/PasswordDigest.java

@@ -0,0 +1,98 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+
+/**
+ * A hashed digest of a secret password (used to set control connection
+ * security.)
+ *
+ * For the actual hashing algorithm, see RFC2440's secret-to-key conversion.
+ */
+public class PasswordDigest {
+
+    private final byte[] secret;
+    private final String hashedKey;
+
+    /** Return a new password digest with a random secret and salt. */
+    public static PasswordDigest generateDigest() {
+        byte[] secret = new byte[20];
+        SecureRandom rng = new SecureRandom();
+        rng.nextBytes(secret);
+        return new PasswordDigest(secret);
+    }
+
+    /** Construct a new password digest with a given secret and random salt */
+    public PasswordDigest(byte[] secret) {
+        this(secret, null);
+    }
+
+    /** Construct a new password digest with a given secret and random salt.
+     * Note that the 9th byte of the specifier determines the number of hash
+     * iterations as in RFC2440.
+     */
+    public PasswordDigest(byte[] secret, byte[] specifier) {
+        this.secret = secret.clone();
+        if (specifier == null) {
+            specifier = new byte[9];
+            SecureRandom rng = new SecureRandom();
+            rng.nextBytes(specifier);
+            specifier[8] = 96;
+        }
+        hashedKey = "16:"+encodeBytes(secretToKey(secret, specifier));
+    }
+
+    /** Return the secret used to generate this password hash.
+     */
+    public byte[] getSecret() {
+        return secret.clone();
+    }
+
+    /** Return the hashed password in the format used by Tor. */
+    public String getHashedPassword() {
+        return hashedKey;
+    }
+
+    /** Parameter used by RFC2440's s2k algorithm. */
+    private static final int EXPBIAS = 6;
+
+    /** Implement rfc2440 s2k */
+    public static byte[] secretToKey(byte[] secret, byte[] specifier) {
+        MessageDigest d;
+        try {
+            d = MessageDigest.getInstance("SHA-1");
+        } catch (NoSuchAlgorithmException ex) {
+            throw new RuntimeException("Can't run without sha-1.");
+        }
+        int c = (specifier[8])&0xff;
+        int count = (16 + (c&15)) << ((c>>4) + EXPBIAS);
+
+        byte[] tmp = new byte[8+secret.length];
+        System.arraycopy(specifier, 0, tmp, 0, 8);
+        System.arraycopy(secret, 0, tmp, 8, secret.length);
+        while (count > 0) {
+            if (count >= tmp.length) {
+                d.update(tmp);
+                count -= tmp.length;
+            } else {
+                d.update(tmp, 0, count);
+                count = 0;
+            }
+        }
+        byte[] key = new byte[20+9];
+        System.arraycopy(d.digest(), 0, key, 9, 20);
+        System.arraycopy(specifier, 0, key, 0, 9);
+        return key;
+    }
+
+    /** Return a hexadecimal encoding of a byte array. */
+    // XXX There must be a better way to do this in Java.
+    private static final String encodeBytes(byte[] ba) {
+        return Bytes.hex(ba);
+    }
+
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/README

@@ -0,0 +1,4 @@
+We broke the version detection stuff in Tor 0.1.2.16 / 0.2.0.4-alpha.
+Somebody should rip out the v0 control protocol stuff from here, and
+it should start working again. -RD
+

bramble-core/src/main/java/net/freehaven/tor/control/TorControlCommands.java

@@ -0,0 +1,151 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+/** Interface defining constants used by the Tor controller protocol.
+ */
+// XXXX Take documentation for these from control-spec.txt
+public interface TorControlCommands {
+
+    public static final short CMD_ERROR = 0x0000;
+    public static final short CMD_DONE = 0x0001;
+    public static final short CMD_SETCONF = 0x0002;
+    public static final short CMD_GETCONF = 0x0003;
+    public static final short CMD_CONFVALUE = 0x0004;
+    public static final short CMD_SETEVENTS = 0x0005;
+    public static final short CMD_EVENT = 0x0006;
+    public static final short CMD_AUTH = 0x0007;
+    public static final short CMD_SAVECONF = 0x0008;
+    public static final short CMD_SIGNAL = 0x0009;
+    public static final short CMD_MAPADDRESS = 0x000A;
+    public static final short CMD_GETINFO = 0x000B;
+    public static final short CMD_INFOVALUE = 0x000C;
+    public static final short CMD_EXTENDCIRCUIT = 0x000D;
+    public static final short CMD_ATTACHSTREAM = 0x000E;
+    public static final short CMD_POSTDESCRIPTOR = 0x000F;
+    public static final short CMD_FRAGMENTHEADER = 0x0010;
+    public static final short CMD_FRAGMENT = 0x0011;
+    public static final short CMD_REDIRECTSTREAM = 0x0012;
+    public static final short CMD_CLOSESTREAM = 0x0013;
+    public static final short CMD_CLOSECIRCUIT = 0x0014;
+
+    public static final String[] CMD_NAMES = {
+        "ERROR",
+        "DONE",
+        "SETCONF",
+        "GETCONF",
+        "CONFVALUE",
+        "SETEVENTS",
+        "EVENT",
+        "AUTH",
+        "SAVECONF",
+        "SIGNAL",
+        "MAPADDRESS",
+        "GETINFO",
+        "INFOVALUE",
+        "EXTENDCIRCUIT",
+        "ATTACHSTREAM",
+        "POSTDESCRIPTOR",
+        "FRAGMENTHEADER",
+        "FRAGMENT",
+        "REDIRECTSTREAM",
+        "CLOSESTREAM",
+        "CLOSECIRCUIT",
+    };
+
+    public static final short EVENT_CIRCSTATUS = 0x0001;
+    public static final short EVENT_STREAMSTATUS = 0x0002;
+    public static final short EVENT_ORCONNSTATUS = 0x0003;
+    public static final short EVENT_BANDWIDTH = 0x0004;
+    public static final short EVENT_NEWDESCRIPTOR = 0x0006;
+    public static final short EVENT_MSG_DEBUG = 0x0007;
+    public static final short EVENT_MSG_INFO = 0x0008;
+    public static final short EVENT_MSG_NOTICE = 0x0009;
+    public static final short EVENT_MSG_WARN = 0x000A;
+    public static final short EVENT_MSG_ERROR = 0x000B;
+
+    public static final String[] EVENT_NAMES = {
+        "(0)",
+        "CIRC",
+        "STREAM",
+        "ORCONN",
+        "BW",
+        "OLDLOG",
+        "NEWDESC",
+        "DEBUG",
+        "INFO",
+        "NOTICE",
+        "WARN",
+        "ERR",
+    };
+
+    public static final byte CIRC_STATUS_LAUNCHED = 0x01;
+    public static final byte CIRC_STATUS_BUILT = 0x02;
+    public static final byte CIRC_STATUS_EXTENDED = 0x03;
+    public static final byte CIRC_STATUS_FAILED = 0x04;
+    public static final byte CIRC_STATUS_CLOSED = 0x05;
+
+    public static final String[] CIRC_STATUS_NAMES = {
+        "LAUNCHED",
+        "BUILT",
+        "EXTENDED",
+        "FAILED",
+        "CLOSED",
+    };
+
+    public static final byte STREAM_STATUS_SENT_CONNECT = 0x00;
+    public static final byte STREAM_STATUS_SENT_RESOLVE = 0x01;
+    public static final byte STREAM_STATUS_SUCCEEDED = 0x02;
+    public static final byte STREAM_STATUS_FAILED = 0x03;
+    public static final byte STREAM_STATUS_CLOSED = 0x04;
+    public static final byte STREAM_STATUS_NEW_CONNECT = 0x05;
+    public static final byte STREAM_STATUS_NEW_RESOLVE = 0x06;
+    public static final byte STREAM_STATUS_DETACHED = 0x07;
+
+    public static final String[] STREAM_STATUS_NAMES = {
+        "SENT_CONNECT",
+        "SENT_RESOLVE",
+        "SUCCEEDED",
+        "FAILED",
+        "CLOSED",
+        "NEW_CONNECT",
+        "NEW_RESOLVE",
+        "DETACHED"
+    };
+
+    public static final byte OR_CONN_STATUS_LAUNCHED = 0x00;
+    public static final byte OR_CONN_STATUS_CONNECTED = 0x01;
+    public static final byte OR_CONN_STATUS_FAILED = 0x02;
+    public static final byte OR_CONN_STATUS_CLOSED = 0x03;
+
+    public static final String[] OR_CONN_STATUS_NAMES = {
+        "LAUNCHED","CONNECTED","FAILED","CLOSED"
+    };
+
+    public static final byte SIGNAL_HUP = 0x01;
+    public static final byte SIGNAL_INT = 0x02;
+    public static final byte SIGNAL_USR1 = 0x0A;
+    public static final byte SIGNAL_USR2 = 0x0C;
+    public static final byte SIGNAL_TERM = 0x0F;
+
+    public static final String ERROR_MSGS[] = {
+        "Unspecified error",
+        "Internal error",
+        "Unrecognized message type",
+        "Syntax error",
+        "Unrecognized configuration key",
+        "Invalid configuration value",
+        "Unrecognized byte code",
+        "Unauthorized",
+        "Failed authentication attempt",
+        "Resource exhausted",
+        "No such stream",
+        "No such circuit",
+        "No such OR",
+    };
+
+    public static final String HS_ADDRESS = "onionAddress";
+    public static final String HS_PRIVKEY = "onionPrivKey";
+
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/TorControlConnection.java

@@ -0,0 +1,998 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintStream;
+import java.io.PrintWriter;
+import java.io.Reader;
+import java.io.Writer;
+import java.net.Socket;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.StringTokenizer;
+import java.util.logging.Logger;
+
+import static java.util.logging.Logger.getLogger;
+
+/**
+ * A connection to a running Tor process as specified in control-spec.txt.
+ */
+public class TorControlConnection implements TorControlCommands {
+
+	private static final Logger LOG =
+			getLogger(TorControlConnection.class.getName());
+
+	private final LinkedList<Waiter> waiters;
+	private final BufferedReader input;
+	private final Writer output;
+
+	private ControlParseThread thread; // Locking: this
+
+	private volatile EventHandler handler;
+	private volatile PrintWriter debugOutput;
+	private volatile IOException parseThreadException;
+
+	static class Waiter {
+
+		List<ReplyLine> response; // Locking: this
+		boolean interrupted;
+
+		List<ReplyLine> getResponse() throws InterruptedException {
+			LOG.info("Entering synchronized (waiter " + hashCode() + ")");
+			synchronized (this) {
+				LOG.info("Entered synchronized (waiter " + hashCode() + ")");
+				while (response == null) {
+					LOG.info("Waiter " + hashCode() + " waiting for response");
+					wait();
+					if (interrupted) {
+						LOG.info("Waiter " + hashCode() + " interrupted");
+						throw new InterruptedException();
+					}
+				}
+				LOG.info("Waiter " + hashCode() + " got response " + response);
+				LOG.info("Leaving synchronized (waiter " + hashCode() + ")");
+				return response;
+			}
+		}
+
+		void setResponse(List<ReplyLine> response) {
+			LOG.info("Entering synchronized (waiter " + hashCode() + ")");
+			synchronized (this) {
+				LOG.info("Entered synchronized (waiter " + hashCode() + ")");
+				LOG.info("Setting response for waiter " + hashCode() + ": "
+						+ response);
+				this.response = response;
+				notifyAll();
+				LOG.info("Leaving synchronized (waiter " + hashCode() + ")");
+			}
+		}
+
+		void interrupt() {
+			LOG.info("Entering synchronized (waiter " + hashCode() + ")");
+			synchronized (this) {
+				LOG.info("Entered synchronized (waiter " + hashCode() + ")");
+				LOG.info("Interrupting waiter " + hashCode());
+				interrupted = true;
+				notifyAll();
+				LOG.info("Leaving synchronized (waiter " + hashCode() + ")");
+			}
+		}
+	}
+
+	static class ReplyLine {
+
+		final String status;
+		final String msg;
+		final String rest;
+
+		ReplyLine(String status, String msg, String rest) {
+			this.status = status;
+			this.msg = msg;
+			this.rest = rest;
+		}
+
+		@Override
+		public String toString() {
+			return status + " " + msg + " " + rest;
+		}
+	}
+
+	/**
+	 * Create a new TorControlConnection to communicate with Tor over
+	 * a given socket.  After calling this constructor, it is typical to
+	 * call launchThread and authenticate.
+	 */
+	public TorControlConnection(Socket connection) throws IOException {
+		this(connection.getInputStream(), connection.getOutputStream());
+	}
+
+	/**
+	 * Create a new TorControlConnection to communicate with Tor over
+	 * an arbitrary pair of data streams.
+	 */
+	public TorControlConnection(InputStream i, OutputStream o) {
+		this(new InputStreamReader(i), new OutputStreamWriter(o));
+	}
+
+	public TorControlConnection(Reader i, Writer o) {
+		this.output = o;
+		if (i instanceof BufferedReader)
+			this.input = (BufferedReader) i;
+		else
+			this.input = new BufferedReader(i);
+		this.waiters = new LinkedList<>();
+	}
+
+	protected final void writeEscaped(String s) throws IOException {
+		StringTokenizer st = new StringTokenizer(s, "\n");
+		while (st.hasMoreTokens()) {
+			String line = st.nextToken();
+			if (line.startsWith("."))
+				line = "." + line;
+			if (line.endsWith("\r"))
+				line += "\n";
+			else
+				line += "\r\n";
+			if (debugOutput != null)
+				debugOutput.print(">> " + line);
+			output.write(line);
+		}
+		output.write(".\r\n");
+		if (debugOutput != null)
+			debugOutput.print(">> .\n");
+	}
+
+	protected static String quote(String s) {
+		StringBuffer sb = new StringBuffer("\"");
+		for (int i = 0; i < s.length(); ++i) {
+			char c = s.charAt(i);
+			switch (c) {
+				case '\r':
+				case '\n':
+				case '\\':
+				case '\"':
+					sb.append('\\');
+			}
+			sb.append(c);
+		}
+		sb.append('\"');
+		return sb.toString();
+	}
+
+	protected final ArrayList<ReplyLine> readReply() throws IOException {
+		ArrayList<ReplyLine> reply = new ArrayList<>();
+		char c;
+		do {
+			String line = input.readLine();
+			if (line == null) {
+				// if line is null, the end of the stream has been reached, i.e.
+				// the connection to Tor has been closed!
+				if (reply.isEmpty()) {
+					// nothing received so far, can exit cleanly
+					return reply;
+				}
+				// received half of a reply before the connection broke down
+				throw new TorControlSyntaxError("Connection to Tor " +
+						" broke down while receiving reply!");
+			}
+			if (debugOutput != null)
+				debugOutput.println("<< " + line);
+			if (line.length() < 4)
+				throw new TorControlSyntaxError(
+						"Line (\"" + line + "\") too short");
+			String status = line.substring(0, 3);
+			c = line.charAt(3);
+			String msg = line.substring(4);
+			String rest = null;
+			if (c == '+') {
+				StringBuffer data = new StringBuffer();
+				while (true) {
+					line = input.readLine();
+					if (debugOutput != null)
+						debugOutput.print("<< " + line);
+					if (line.equals("."))
+						break;
+					else if (line.startsWith("."))
+						line = line.substring(1);
+					data.append(line).append('\n');
+				}
+				rest = data.toString();
+			}
+			reply.add(new ReplyLine(status, msg, rest));
+		} while (c != ' ');
+
+		return reply;
+	}
+
+	protected List<ReplyLine> sendAndWaitForResponse(String s,
+			String rest) throws IOException {
+		LOG.info("Entering synchronized (connection)");
+		synchronized (this) {
+			LOG.info("Entered synchronized (connection)");
+			LOG.info("Sending '" + s + "', '" + rest +
+					"' and waiting for response");
+			if (parseThreadException != null) {
+				LOG.info("Throwing previously caught exception "
+						+ parseThreadException);
+				throw parseThreadException;
+			}
+			checkThread();
+			Waiter w = new Waiter();
+			LOG.info("Created waiter " + w.hashCode());
+			if (debugOutput != null)
+				debugOutput.print(">> " + s);
+			LOG.info("Entering synchronized (waiters)");
+			synchronized (waiters) {
+				LOG.info("Entered synchronized (waiters)");
+				output.write(s);
+				LOG.info("Wrote '" + s + "'");
+				if (rest != null) {
+					writeEscaped(rest);
+					LOG.info("Wrote escaped '" + rest + "'");
+				}
+				output.flush();
+				LOG.info("Flushed output");
+				waiters.addLast(w);
+				LOG.info("Added waiter, " + waiters.size() + " waiting");
+				LOG.info("Leaving synchronized (waiters)");
+			}
+			List<ReplyLine> lst;
+			try {
+				LOG.info("Getting response from waiter " + w.hashCode());
+				lst = w.getResponse();
+				LOG.info("Got response from waiter " + w.hashCode() + ": " +
+						lst);
+			} catch (InterruptedException ex) {
+				throw new IOException("Interrupted");
+			}
+			for (Iterator<ReplyLine> i = lst.iterator(); i.hasNext(); ) {
+				ReplyLine c = i.next();
+				if (!c.status.startsWith("2"))
+					throw new TorControlError("Error reply: " + c.msg);
+			}
+			LOG.info("Leaving synchronized (connection)");
+			return lst;
+		}
+	}
+
+	/**
+	 * Helper: decode a CMD_EVENT command and dispatch it to our
+	 * EventHandler (if any).
+	 */
+	protected void handleEvent(ArrayList<ReplyLine> events) {
+		if (handler == null)
+			return;
+
+		for (Iterator<ReplyLine> i = events.iterator(); i.hasNext(); ) {
+			ReplyLine line = i.next();
+			int idx = line.msg.indexOf(' ');
+			String tp = line.msg.substring(0, idx).toUpperCase();
+			String rest = line.msg.substring(idx + 1);
+			if (tp.equals("CIRC")) {
+				List<String> lst = Bytes.splitStr(null, rest);
+				handler.circuitStatus(lst.get(1),
+						lst.get(0),
+						lst.get(1).equals("LAUNCHED")
+								|| lst.size() < 3 ? ""
+								: lst.get(2));
+			} else if (tp.equals("STREAM")) {
+				List<String> lst = Bytes.splitStr(null, rest);
+				handler.streamStatus(lst.get(1),
+						lst.get(0),
+						lst.get(3));
+				// XXXX circID.
+			} else if (tp.equals("ORCONN")) {
+				List<String> lst = Bytes.splitStr(null, rest);
+				handler.orConnStatus(lst.get(1), lst.get(0));
+			} else if (tp.equals("BW")) {
+				List<String> lst = Bytes.splitStr(null, rest);
+				handler.bandwidthUsed(Integer.parseInt(lst.get(0)),
+						Integer.parseInt(lst.get(1)));
+			} else if (tp.equals("NEWDESC")) {
+				List<String> lst = Bytes.splitStr(null, rest);
+				handler.newDescriptors(lst);
+			} else if (tp.equals("DEBUG") ||
+					tp.equals("INFO") ||
+					tp.equals("NOTICE") ||
+					tp.equals("WARN") ||
+					tp.equals("ERR")) {
+				handler.message(tp, rest);
+			} else {
+				handler.unrecognized(tp, rest);
+			}
+		}
+	}
+
+
+	/**
+	 * Sets <b>w</b> as the PrintWriter for debugging output,
+	 * which writes out all messages passed between Tor and the controller.
+	 * Outgoing messages are preceded by "\>\>" and incoming messages are preceded
+	 * by "\<\<"
+	 */
+	public void setDebugging(PrintWriter w) {
+		debugOutput = w;
+	}
+
+	/**
+	 * Sets <b>s</b> as the PrintStream for debugging output,
+	 * which writes out all messages passed between Tor and the controller.
+	 * Outgoing messages are preceded by "\>\>" and incoming messages are preceded
+	 * by "\<\<"
+	 */
+	public void setDebugging(PrintStream s) {
+		debugOutput = new PrintWriter(s, true);
+	}
+
+	/**
+	 * Set the EventHandler object that will be notified of any
+	 * events Tor delivers to this connection.  To make Tor send us
+	 * events, call setEvents().
+	 */
+	public void setEventHandler(EventHandler handler) {
+		this.handler = handler;
+	}
+
+	/**
+	 * Start a thread to react to Tor's responses in the background.
+	 * This is necessary to handle asynchronous events and synchronous
+	 * responses that arrive independantly over the same socket.
+	 */
+	public Thread launchThread(boolean daemon) {
+		LOG.info("Entering synchronized (connection)");
+		synchronized (this) {
+			LOG.info("Entered synchronized (connection)");
+			ControlParseThread th = new ControlParseThread();
+			LOG.info("Launching parse thread " + th.hashCode());
+			if (daemon)
+				th.setDaemon(true);
+			th.start();
+			this.thread = th;
+			LOG.info("Leaving synchronized (connection)");
+			return th;
+		}
+	}
+
+	protected class ControlParseThread extends Thread {
+
+		@Override
+		public void run() {
+			try {
+				react();
+			} catch (IOException ex) {
+				LOG.info("Parse thread " + hashCode()
+						+ " caught exception " + ex);
+				parseThreadException = ex;
+			}
+		}
+	}
+
+	protected void checkThread() {
+		LOG.info("Entering synchronized (connection)");
+		synchronized (this) {
+			LOG.info("Entered synchronized (connection)");
+			if (thread == null)
+				launchThread(true);
+			LOG.info("Leaving synchronized (connection)");
+		}
+	}
+
+	/**
+	 * helper: implement the main background loop.
+	 */
+	protected void react() throws IOException {
+		while (true) {
+			ArrayList<ReplyLine> lst = readReply();
+			LOG.info("Read reply: " + lst);
+			if (lst.isEmpty()) {
+				// interrupted queued waiters, there won't be any response.
+				LOG.info("Entering synchronized (waiters)");
+				synchronized (waiters) {
+					LOG.info("Entered synchronized (waiters)");
+					if (!waiters.isEmpty()) {
+						for (Waiter w : waiters) {
+							LOG.info("Interrupting waiter " + w.hashCode());
+							w.interrupt();
+						}
+					} else {
+						LOG.info("No waiters");
+					}
+					LOG.info("Leaving synchronized (waiters)");
+				}
+				throw new IOException("Tor is no longer running");
+			}
+			if ((lst.get(0)).status.startsWith("6")) {
+				LOG.info("Reply is an event");
+				handleEvent(lst);
+			} else {
+				LOG.info("Entering synchronized (waiters)");
+				synchronized (waiters) {
+					LOG.info("Entered synchronized (waiters)");
+					if (!waiters.isEmpty()) {
+						Waiter w;
+						w = waiters.removeFirst();
+						LOG.info("Setting response for waiter " + w.hashCode());
+						w.setResponse(lst);
+					} else {
+						LOG.info("No waiters");
+					}
+					LOG.info("Leaving synchronized (waiters)");
+				}
+
+			}
+		}
+	}
+
+	/**
+	 * Change the value of the configuration option 'key' to 'val'.
+	 */
+	public void setConf(String key, String value) throws IOException {
+		List<String> lst = new ArrayList<>();
+		lst.add(key + " " + value);
+		setConf(lst);
+	}
+
+	/**
+	 * Change the values of the configuration options stored in kvMap.
+	 */
+	public void setConf(Map<String, String> kvMap) throws IOException {
+		List<String> lst = new ArrayList<>();
+		for (Iterator<Map.Entry<String, String>> it =
+				kvMap.entrySet().iterator(); it.hasNext(); ) {
+			Map.Entry<String, String> ent = it.next();
+			lst.add(ent.getKey() + " " + ent.getValue() + "\n");
+		}
+		setConf(lst);
+	}
+
+	/**
+	 * Changes the values of the configuration options stored in
+	 * <b>kvList</b>.  Each list element in <b>kvList</b> is expected to be
+	 * String of the format "key value".
+	 * <p>
+	 * Tor behaves as though it had just read each of the key-value pairs
+	 * from its configuration file.  Keywords with no corresponding values have
+	 * their configuration values reset to their defaults.  setConf is
+	 * all-or-nothing: if there is an error in any of the configuration settings,
+	 * Tor sets none of them.
+	 * <p>
+	 * When a configuration option takes multiple values, or when multiple
+	 * configuration keys form a context-sensitive group (see getConf below), then
+	 * setting any of the options in a setConf command is taken to reset all of
+	 * the others.  For example, if two ORBindAddress values are configured, and a
+	 * command arrives containing a single ORBindAddress value, the new
+	 * command's value replaces the two old values.
+	 * <p>
+	 * To remove all settings for a given option entirely (and go back to its
+	 * default value), include a String in <b>kvList</b> containing the key and no value.
+	 */
+	public void setConf(Collection<String> kvList) throws IOException {
+		if (kvList.size() == 0)
+			return;
+		StringBuffer b = new StringBuffer("SETCONF");
+		for (Iterator<String> it = kvList.iterator(); it.hasNext(); ) {
+			String kv = it.next();
+			int i = kv.indexOf(' ');
+			if (i == -1)
+				b.append(" ").append(kv);
+			b.append(" ").append(kv.substring(0, i)).append("=")
+					.append(quote(kv.substring(i + 1)));
+		}
+		b.append("\r\n");
+		sendAndWaitForResponse(b.toString(), null);
+	}
+
+	/**
+	 * Try to reset the values listed in the collection 'keys' to their
+	 * default values.
+	 **/
+	public void resetConf(Collection<String> keys) throws IOException {
+		if (keys.size() == 0)
+			return;
+		StringBuffer b = new StringBuffer("RESETCONF");
+		for (Iterator<String> it = keys.iterator(); it.hasNext(); ) {
+			String key = it.next();
+			b.append(" ").append(key);
+		}
+		b.append("\r\n");
+		sendAndWaitForResponse(b.toString(), null);
+	}
+
+	/**
+	 * Return the value of the configuration option 'key'
+	 */
+	public List<ConfigEntry> getConf(String key) throws IOException {
+		List<String> lst = new ArrayList<>();
+		lst.add(key);
+		return getConf(lst);
+	}
+
+	/**
+	 * Requests the values of the configuration variables listed in <b>keys</b>.
+	 * Results are returned as a list of ConfigEntry objects.
+	 * <p>
+	 * If an option appears multiple times in the configuration, all of its
+	 * key-value pairs are returned in order.
+	 * <p>
+	 * Some options are context-sensitive, and depend on other options with
+	 * different keywords.  These cannot be fetched directly.  Currently there
+	 * is only one such option: clients should use the "HiddenServiceOptions"
+	 * virtual keyword to get all HiddenServiceDir, HiddenServicePort,
+	 * HiddenServiceNodes, and HiddenServiceExcludeNodes option settings.
+	 */
+	public List<ConfigEntry> getConf(Collection<String> keys)
+			throws IOException {
+		StringBuffer sb = new StringBuffer("GETCONF");
+		for (Iterator<String> it = keys.iterator(); it.hasNext(); ) {
+			String key = it.next();
+			sb.append(" ").append(key);
+		}
+		sb.append("\r\n");
+		List<ReplyLine> lst = sendAndWaitForResponse(sb.toString(), null);
+		List<ConfigEntry> result = new ArrayList<>();
+		for (Iterator<ReplyLine> it = lst.iterator(); it.hasNext(); ) {
+			String kv = (it.next()).msg;
+			int idx = kv.indexOf('=');
+			if (idx >= 0)
+				result.add(new ConfigEntry(kv.substring(0, idx),
+						kv.substring(idx + 1)));
+			else
+				result.add(new ConfigEntry(kv));
+		}
+		return result;
+	}
+
+	/**
+	 * Request that the server inform the client about interesting events.
+	 * Each element of <b>events</b> is one of the following Strings:
+	 * ["CIRC" | "STREAM" | "ORCONN" | "BW" | "DEBUG" |
+	 * "INFO" | "NOTICE" | "WARN" | "ERR" | "NEWDESC" | "ADDRMAP"] .
+	 * <p>
+	 * Any events not listed in the <b>events</b> are turned off; thus, calling
+	 * setEvents with an empty <b>events</b> argument turns off all event reporting.
+	 */
+	public void setEvents(List<String> events) throws IOException {
+		StringBuffer sb = new StringBuffer("SETEVENTS");
+		for (Iterator<String> it = events.iterator(); it.hasNext(); ) {
+			sb.append(" ").append(it.next());
+		}
+		sb.append("\r\n");
+		sendAndWaitForResponse(sb.toString(), null);
+	}
+
+	/**
+	 * Authenticates the controller to the Tor server.
+	 * <p>
+	 * By default, the current Tor implementation trusts all local users, and
+	 * the controller can authenticate itself by calling authenticate(new byte[0]).
+	 * <p>
+	 * If the 'CookieAuthentication' option is true, Tor writes a "magic cookie"
+	 * file named "control_auth_cookie" into its data directory.  To authenticate,
+	 * the controller must send the contents of this file in <b>auth</b>.
+	 * <p>
+	 * If the 'HashedControlPassword' option is set, <b>auth</b> must contain the salted
+	 * hash of a secret password.  The salted hash is computed according to the
+	 * S2K algorithm in RFC 2440 (OpenPGP), and prefixed with the s2k specifier.
+	 * This is then encoded in hexadecimal, prefixed by the indicator sequence
+	 * "16:".
+	 * <p>
+	 * You can generate the salt of a password by calling
+	 * 'tor --hash-password <password>'
+	 * or by using the provided PasswordDigest class.
+	 * To authenticate under this scheme, the controller sends Tor the original
+	 * secret that was used to generate the password.
+	 */
+	public void authenticate(byte[] auth) throws IOException {
+		String cmd = "AUTHENTICATE " + Bytes.hex(auth) + "\r\n";
+		sendAndWaitForResponse(cmd, null);
+	}
+
+	/**
+	 * Instructs the server to write out its configuration options into its torrc.
+	 */
+	public void saveConf() throws IOException {
+		sendAndWaitForResponse("SAVECONF\r\n", null);
+	}
+
+	/**
+	 * Sends a signal from the controller to the Tor server.
+	 * <b>signal</b> is one of the following Strings:
+	 * <ul>
+	 * <li>"RELOAD" or "HUP" :  Reload config items, refetch directory</li>
+	 * <li>"SHUTDOWN" or "INT" : Controlled shutdown: if server is an OP, exit immediately.
+	 * If it's an OR, close listeners and exit after 30 seconds</li>
+	 * <li>"DUMP" or "USR1" : Dump stats: log information about open connections and circuits</li>
+	 * <li>"DEBUG" or "USR2" : Debug: switch all open logs to loglevel debug</li>
+	 * <li>"HALT" or "TERM" : Immediate shutdown: clean up and exit now</li>
+	 * </ul>
+	 */
+	public void signal(String signal) throws IOException {
+		String cmd = "SIGNAL " + signal + "\r\n";
+		sendAndWaitForResponse(cmd, null);
+	}
+
+	/**
+	 * Send a signal to the Tor process to shut it down or halt it.
+	 * Does not wait for a response.
+	 */
+	public void shutdownTor(String signal) throws IOException {
+		String s = "SIGNAL " + signal + "\r\n";
+		Waiter w = new Waiter();
+		if (debugOutput != null)
+			debugOutput.print(">> " + s);
+		LOG.info("Entering synchronized (waiters)");
+		synchronized (waiters) {
+			LOG.info("Entered synchronized (waiters)");
+			output.write(s);
+			output.flush();
+			LOG.info("Leaving synchronized (waiters)");
+		}
+	}
+
+	/**
+	 * Tells the Tor server that future SOCKS requests for connections to a set of original
+	 * addresses should be replaced with connections to the specified replacement
+	 * addresses.  Each element of <b>kvLines</b> is a String of the form
+	 * "old-address new-address".  This function returns the new address mapping.
+	 * <p>
+	 * The client may decline to provide a body for the original address, and
+	 * instead send a special null address ("0.0.0.0" for IPv4, "::0" for IPv6, or
+	 * "." for hostname), signifying that the server should choose the original
+	 * address itself, and return that address in the reply.  The server
+	 * should ensure that it returns an element of address space that is unlikely
+	 * to be in actual use.  If there is already an address mapped to the
+	 * destination address, the server may reuse that mapping.
+	 * <p>
+	 * If the original address is already mapped to a different address, the old
+	 * mapping is removed.  If the original address and the destination address
+	 * are the same, the server removes any mapping in place for the original
+	 * address.
+	 * <p>
+	 * Mappings set by the controller last until the Tor process exits:
+	 * they never expire. If the controller wants the mapping to last only
+	 * a certain time, then it must explicitly un-map the address when that
+	 * time has elapsed.
+	 */
+	public Map<String, String> mapAddresses(Collection<String> kvLines)
+			throws IOException {
+		StringBuffer sb = new StringBuffer("MAPADDRESS");
+		for (Iterator<String> it = kvLines.iterator(); it.hasNext(); ) {
+			String kv = it.next();
+			int i = kv.indexOf(' ');
+			sb.append(" ").append(kv.substring(0, i)).append("=")
+					.append(quote(kv.substring(i + 1)));
+		}
+		sb.append("\r\n");
+		List<ReplyLine> lst = sendAndWaitForResponse(sb.toString(), null);
+		Map<String, String> result = new HashMap<>();
+		for (Iterator<ReplyLine> it = lst.iterator(); it.hasNext(); ) {
+			String kv = (it.next()).msg;
+			int idx = kv.indexOf('=');
+			result.put(kv.substring(0, idx),
+					kv.substring(idx + 1));
+		}
+		return result;
+	}
+
+	public Map<String, String> mapAddresses(Map<String, String> addresses)
+			throws IOException {
+		List<String> kvList = new ArrayList<>();
+		for (Iterator<Map.Entry<String, String>> it =
+				addresses.entrySet().iterator(); it.hasNext(); ) {
+			Map.Entry<String, String> e = it.next();
+			kvList.add(e.getKey() + " " + e.getValue());
+		}
+		return mapAddresses(kvList);
+	}
+
+	public String mapAddress(String fromAddr, String toAddr)
+			throws IOException {
+		List<String> lst = new ArrayList<>();
+		lst.add(fromAddr + " " + toAddr + "\n");
+		Map<String, String> m = mapAddresses(lst);
+		return m.get(fromAddr);
+	}
+
+	/**
+	 * Queries the Tor server for keyed values that are not stored in the torrc
+	 * configuration file.  Returns a map of keys to values.
+	 * <p>
+	 * Recognized keys include:
+	 * <ul>
+	 * <li>"version" : The version of the server's software, including the name
+	 * of the software. (example: "Tor 0.0.9.4")</li>
+	 * <li>"desc/id/<OR identity>" or "desc/name/<OR nickname>" : the latest server
+	 * descriptor for a given OR, NUL-terminated.  If no such OR is known, the
+	 * corresponding value is an empty string.</li>
+	 * <li>"network-status" : a space-separated list of all known OR identities.
+	 * This is in the same format as the router-status line in directories;
+	 * see tor-spec.txt for details.</li>
+	 * <li>"addr-mappings/all"</li>
+	 * <li>"addr-mappings/config"</li>
+	 * <li>"addr-mappings/cache"</li>
+	 * <li>"addr-mappings/control" : a space-separated list of address mappings, each
+	 * in the form of "from-address=to-address".  The 'config' key
+	 * returns those address mappings set in the configuration; the 'cache'
+	 * key returns the mappings in the client-side DNS cache; the 'control'
+	 * key returns the mappings set via the control interface; the 'all'
+	 * target returns the mappings set through any mechanism.</li>
+	 * <li>"circuit-status" : A series of lines as for a circuit status event. Each line is of the form:
+	 * "CircuitID CircStatus Path"</li>
+	 * <li>"stream-status" : A series of lines as for a stream status event.  Each is of the form:
+	 * "StreamID StreamStatus CircID Target"</li>
+	 * <li>"orconn-status" : A series of lines as for an OR connection status event.  Each is of the
+	 * form: "ServerID ORStatus"</li>
+	 * </ul>
+	 */
+	public Map<String, String> getInfo(Collection<String> keys)
+			throws IOException {
+		StringBuffer sb = new StringBuffer("GETINFO");
+		for (Iterator<String> it = keys.iterator(); it.hasNext(); ) {
+			sb.append(" ").append(it.next());
+		}
+		sb.append("\r\n");
+		List<ReplyLine> lst = sendAndWaitForResponse(sb.toString(), null);
+		Map<String, String> m = new HashMap<>();
+		for (Iterator<ReplyLine> it = lst.iterator(); it.hasNext(); ) {
+			ReplyLine line = it.next();
+			int idx = line.msg.indexOf('=');
+			if (idx < 0)
+				break;
+			String k = line.msg.substring(0, idx);
+			String v;
+			if (line.rest != null) {
+				v = line.rest;
+			} else {
+				v = line.msg.substring(idx + 1);
+			}
+			m.put(k, v);
+		}
+		return m;
+	}
+
+
+	/**
+	 * Return the value of the information field 'key'
+	 */
+	public String getInfo(String key) throws IOException {
+		List<String> lst = new ArrayList<>();
+		lst.add(key);
+		Map<String, String> m = getInfo(lst);
+		return m.get(key);
+	}
+
+	/**
+	 * An extendCircuit request takes one of two forms: either the <b>circID</b> is zero, in
+	 * which case it is a request for the server to build a new circuit according
+	 * to the specified path, or the <b>circID</b> is nonzero, in which case it is a
+	 * request for the server to extend an existing circuit with that ID according
+	 * to the specified <b>path</b>.
+	 * <p>
+	 * If successful, returns the Circuit ID of the (maybe newly created) circuit.
+	 */
+	public String extendCircuit(String circID, String path) throws IOException {
+		List<ReplyLine> lst = sendAndWaitForResponse(
+				"EXTENDCIRCUIT " + circID + " " + path + "\r\n", null);
+		return (lst.get(0)).msg;
+	}
+
+	/**
+	 * Informs the Tor server that the stream specified by <b>streamID</b> should be
+	 * associated with the circuit specified by <b>circID</b>.
+	 * <p>
+	 * Each stream may be associated with
+	 * at most one circuit, and multiple streams may share the same circuit.
+	 * Streams can only be attached to completed circuits (that is, circuits that
+	 * have sent a circuit status "BUILT" event or are listed as built in a
+	 * getInfo circuit-status request).
+	 * <p>
+	 * If <b>circID</b> is 0, responsibility for attaching the given stream is
+	 * returned to Tor.
+	 * <p>
+	 * By default, Tor automatically attaches streams to
+	 * circuits itself, unless the configuration variable
+	 * "__LeaveStreamsUnattached" is set to "1".  Attempting to attach streams
+	 * via TC when "__LeaveStreamsUnattached" is false may cause a race between
+	 * Tor and the controller, as both attempt to attach streams to circuits.
+	 */
+	public void attachStream(String streamID, String circID)
+			throws IOException {
+		sendAndWaitForResponse(
+				"ATTACHSTREAM " + streamID + " " + circID + "\r\n", null);
+	}
+
+	/**
+	 * Tells Tor about the server descriptor in <b>desc</b>.
+	 * <p>
+	 * The descriptor, when parsed, must contain a number of well-specified
+	 * fields, including fields for its nickname and identity.
+	 */
+	// More documentation here on format of desc?
+	// No need for return value?  control-spec.txt says reply is merely "250 OK" on success...
+	public String postDescriptor(String desc) throws IOException {
+		List<ReplyLine> lst =
+				sendAndWaitForResponse("+POSTDESCRIPTOR\r\n", desc);
+		return (lst.get(0)).msg;
+	}
+
+	/**
+	 * Tells Tor to change the exit address of the stream identified by <b>streamID</b>
+	 * to <b>address</b>. No remapping is performed on the new provided address.
+	 * <p>
+	 * To be sure that the modified address will be used, this event must be sent
+	 * after a new stream event is received, and before attaching this stream to
+	 * a circuit.
+	 */
+	public void redirectStream(String streamID, String address)
+			throws IOException {
+		sendAndWaitForResponse(
+				"REDIRECTSTREAM " + streamID + " " + address + "\r\n",
+				null);
+	}
+
+	/**
+	 * Tells Tor to close the stream identified by <b>streamID</b>.
+	 * <b>reason</b> should be one of the Tor RELAY_END reasons given in tor-spec.txt, as a decimal:
+	 * <ul>
+	 * <li>1 -- REASON_MISC           (catch-all for unlisted reasons)</li>
+	 * <li>2 -- REASON_RESOLVEFAILED  (couldn't look up hostname)</li>
+	 * <li>3 -- REASON_CONNECTREFUSED (remote host refused connection)</li>
+	 * <li>4 -- REASON_EXITPOLICY     (OR refuses to connect to host or port)</li>
+	 * <li>5 -- REASON_DESTROY        (Circuit is being destroyed)</li>
+	 * <li>6 -- REASON_DONE           (Anonymized TCP connection was closed)</li>
+	 * <li>7 -- REASON_TIMEOUT        (Connection timed out, or OR timed out while connecting)</li>
+	 * <li>8 -- (unallocated)</li>
+	 * <li>9 -- REASON_HIBERNATING    (OR is temporarily hibernating)</li>
+	 * <li>10 -- REASON_INTERNAL       (Internal error at the OR)</li>
+	 * <li>11 -- REASON_RESOURCELIMIT  (OR has no resources to fulfill request)</li>
+	 * <li>12 -- REASON_CONNRESET      (Connection was unexpectedly reset)</li>
+	 * <li>13 -- REASON_TORPROTOCOL    (Sent when closing connection because of Tor protocol violations)</li>
+	 * </ul>
+	 * <p>
+	 * Tor may hold the stream open for a while to flush any data that is pending.
+	 */
+	public void closeStream(String streamID, byte reason)
+			throws IOException {
+		sendAndWaitForResponse(
+				"CLOSESTREAM " + streamID + " " + reason + "\r\n", null);
+	}
+
+	/**
+	 * Tells Tor to close the circuit identified by <b>circID</b>.
+	 * If <b>ifUnused</b> is true, do not close the circuit unless it is unused.
+	 */
+	public void closeCircuit(String circID, boolean ifUnused)
+			throws IOException {
+		sendAndWaitForResponse("CLOSECIRCUIT " + circID +
+				(ifUnused ? " IFUNUSED" : "") + "\r\n", null);
+	}
+
+	/**
+	 * Tells Tor to exit when this control connection is closed. This command
+	 * was added in Tor 0.2.2.28-beta.
+	 */
+	public void takeOwnership() throws IOException {
+		sendAndWaitForResponse("TAKEOWNERSHIP\r\n", null);
+	}
+
+	/**
+	 * Tells Tor to generate and set up a new onion service using the best
+	 * supported algorithm.
+	 * <p/>
+	 * ADD_ONION was added in Tor 0.2.7.1-alpha.
+	 */
+	public Map<String, String> addOnion(Map<Integer, String> portLines)
+			throws IOException {
+		return addOnion("NEW:BEST", portLines, null);
+	}
+
+	/**
+	 * Tells Tor to generate and set up a new onion service using the best
+	 * supported algorithm.
+	 * <p/>
+	 * ADD_ONION was added in Tor 0.2.7.1-alpha.
+	 */
+	public Map<String, String> addOnion(Map<Integer, String> portLines,
+			boolean ephemeral, boolean detach)
+			throws IOException {
+		return addOnion("NEW:BEST", portLines, ephemeral, detach);
+	}
+
+	/**
+	 * Tells Tor to set up an onion service using the provided private key.
+	 * <p/>
+	 * ADD_ONION was added in Tor 0.2.7.1-alpha.
+	 */
+	public Map<String, String> addOnion(String privKey,
+			Map<Integer, String> portLines)
+			throws IOException {
+		return addOnion(privKey, portLines, null);
+	}
+
+	/**
+	 * Tells Tor to set up an onion service using the provided private key.
+	 * <p/>
+	 * ADD_ONION was added in Tor 0.2.7.1-alpha.
+	 */
+	public Map<String, String> addOnion(String privKey,
+			Map<Integer, String> portLines,
+			boolean ephemeral, boolean detach)
+			throws IOException {
+		List<String> flags = new ArrayList<>();
+		if (ephemeral)
+			flags.add("DiscardPK");
+		if (detach)
+			flags.add("Detach");
+		return addOnion(privKey, portLines, flags);
+	}
+
+	/**
+	 * Tells Tor to set up an onion service.
+	 * <p/>
+	 * ADD_ONION was added in Tor 0.2.7.1-alpha.
+	 */
+	public Map<String, String> addOnion(String privKey,
+			Map<Integer, String> portLines,
+			List<String> flags)
+			throws IOException {
+		if (privKey.indexOf(':') < 0)
+			throw new IllegalArgumentException("Invalid privKey");
+		if (portLines == null || portLines.size() < 1)
+			throw new IllegalArgumentException(
+					"Must provide at least one port line");
+		StringBuilder b = new StringBuilder();
+		b.append("ADD_ONION ").append(privKey);
+		if (flags != null && flags.size() > 0) {
+			b.append(" Flags=");
+			String separator = "";
+			for (String flag : flags) {
+				b.append(separator).append(flag);
+				separator = ",";
+			}
+		}
+		for (Map.Entry<Integer, String> portLine : portLines.entrySet()) {
+			int virtPort = portLine.getKey();
+			String target = portLine.getValue();
+			b.append(" Port=").append(virtPort);
+			if (target != null && target.length() > 0)
+				b.append(",").append(target);
+		}
+		b.append("\r\n");
+		List<ReplyLine> lst = sendAndWaitForResponse(b.toString(), null);
+		Map<String, String> ret = new HashMap<>();
+		ret.put(HS_ADDRESS, (lst.get(0)).msg.split("=", 2)[1]);
+		if (lst.size() > 2)
+			ret.put(HS_PRIVKEY, (lst.get(1)).msg.split("=", 2)[1]);
+		return ret;
+	}
+
+	/**
+	 * Tells Tor to take down an onion service previously set up with
+	 * addOnion(). The hostname excludes the .onion extension.
+	 * <p/>
+	 * DEL_ONION was added in Tor 0.2.7.1-alpha.
+	 */
+	public void delOnion(String hostname) throws IOException {
+		sendAndWaitForResponse("DEL_ONION " + hostname + "\r\n", null);
+	}
+
+	/**
+	 * Tells Tor to forget any cached client state relating to the hidden
+	 * service with the given hostname (excluding the .onion extension).
+	 */
+	public void forgetHiddenService(String hostname) throws IOException {
+		sendAndWaitForResponse("HSFORGET " + hostname + "\r\n", null);
+	}
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/TorControlError.java

@@ -0,0 +1,39 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+import java.io.IOException;
+
+/**
+ * An exception raised when Tor tells us about an error.
+ */
+public class TorControlError extends IOException {
+
+    static final long serialVersionUID = 3;
+
+    private final int errorType;
+
+    public TorControlError(int type, String s) {
+        super(s);
+        errorType = type;
+    }
+
+    public TorControlError(String s) {
+        this(-1, s);
+    }
+
+    public int getErrorType() {
+        return errorType;
+    }
+
+    public String getErrorMsg() {
+        try {
+            if (errorType == -1)
+                return null;
+            return TorControlCommands.ERROR_MSGS[errorType];
+        } catch (ArrayIndexOutOfBoundsException ex) {
+            return "Unrecongized error #"+errorType;
+        }
+    }
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/TorControlSyntaxError.java

@@ -0,0 +1,16 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control;
+
+import java.io.IOException;
+
+/**
+ * An exception raised when Tor behaves in an unexpected way.
+ */
+public class TorControlSyntaxError extends IOException {
+
+    static final long serialVersionUID = 3;
+
+    public TorControlSyntaxError(String s) { super(s); }
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/examples/.cvsignore

@@ -0,0 +1 @@
+*.class

bramble-core/src/main/java/net/freehaven/tor/control/examples/DebuggingEventHandler.java

@@ -0,0 +1,44 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control.examples;
+
+import java.io.PrintWriter;
+import java.util.Iterator;
+import net.freehaven.tor.control.EventHandler;
+
+public class DebuggingEventHandler implements EventHandler {
+
+    private final PrintWriter out;
+
+    public DebuggingEventHandler(PrintWriter p) {
+        out = p;
+    }
+
+    public void circuitStatus(String status, String circID, String path) {
+        out.println("Circuit "+circID+" is now "+status+" (path="+path+")");
+    }
+    public void streamStatus(String status, String streamID, String target) {
+        out.println("Stream "+streamID+" is now "+status+" (target="+target+")");
+    }
+    public void orConnStatus(String status, String orName) {
+        out.println("OR connection to "+orName+" is now "+status);
+    }
+    public void bandwidthUsed(long read, long written) {
+        out.println("Bandwidth usage: "+read+" bytes read; "+
+                    written+" bytes written.");
+    }
+    public void newDescriptors(java.util.List<String> orList) {
+        out.println("New descriptors for routers:");
+        for (Iterator<String> i = orList.iterator(); i.hasNext(); )
+            out.println("   "+i.next());
+    }
+    public void message(String type, String msg) {
+        out.println("["+type+"] "+msg.trim());
+    }
+
+    public void unrecognized(String type, String msg) {
+        out.println("unrecognized event ["+type+"] "+msg.trim());
+    }
+
+}
+

bramble-core/src/main/java/net/freehaven/tor/control/examples/Main.java

@@ -0,0 +1,146 @@
+// Copyright 2005 Nick Mathewson, Roger Dingledine
+// See LICENSE file for copying information
+package net.freehaven.tor.control.examples;
+
+import net.freehaven.tor.control.*;
+import java.io.EOFException;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.net.Socket;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Arrays;
+import java.util.Map;
+import java.util.Iterator;
+
+public class Main implements TorControlCommands {
+
+    public static void main(String args[]) {
+        if (args.length < 1) {
+            System.err.println("No command given.");
+            return;
+        }
+        try {
+            if (args[0].equals("set-config")) {
+                setConfig(args);
+            } else if (args[0].equals("get-config")) {
+                getConfig(args);
+            } else if (args[0].equals("get-info")) {
+                getInfo(args);
+            } else if (args[0].equals("listen")) {
+                listenForEvents(args);
+            } else if (args[0].equals("signal")) {
+                signal(args);
+            } else if (args[0].equals("auth")) {
+                authDemo(args);
+            } else {
+                System.err.println("Unrecognized command: "+args[0]);
+            }
+        } catch (EOFException ex) {
+            System.out.println("Control socket closed by Tor.");
+        } catch (TorControlError ex) {
+            System.err.println("Error from Tor process: "+
+                               ex+" ["+ex.getErrorMsg()+"]");
+        } catch (IOException ex) {
+            System.err.println("IO exception when talking to Tor process: "+
+                               ex);
+            ex.printStackTrace(System.err);
+        }
+    }
+
+    private static TorControlConnection getConnection(String[] args,
+        boolean daemon) throws IOException {
+        Socket s = new Socket("127.0.0.1", 9100);
+        TorControlConnection conn = new TorControlConnection(s);
+        conn.launchThread(daemon);
+        conn.authenticate(new byte[0]);
+        return conn;
+    }
+
+    private static TorControlConnection getConnection(String[] args)
+        throws IOException {
+        return getConnection(args, true);
+    }
+
+    public static void setConfig(String[] args) throws IOException {
+        // Usage: "set-config [-save] key value key value key value"
+        TorControlConnection conn = getConnection(args);
+        ArrayList<String> lst = new ArrayList<String>();
+        int i = 1;
+        boolean save = false;
+        if (args[i].equals("-save")) {
+            save = true;
+            ++i;
+        }
+        for (; i < args.length; i +=2) {
+            lst.add(args[i]+" "+args[i+1]);
+        }
+        conn.setConf(lst);
+        if (save) {
+            conn.saveConf();
+        }
+    }
+
+    public static void getConfig(String[] args) throws IOException {
+        // Usage: get-config key key key
+        TorControlConnection conn = getConnection(args);
+        List<ConfigEntry> lst = conn.getConf(Arrays.asList(args).subList(1,args.length));
+        for (Iterator<ConfigEntry> i = lst.iterator(); i.hasNext(); ) {
+            ConfigEntry e = i.next();
+            System.out.println("KEY: "+e.key);
+            System.out.println("VAL: "+e.value);
+        }
+    }
+
+    public static void getInfo(String[] args) throws IOException {
+        TorControlConnection conn = getConnection(args);
+        Map<String,String> m = conn.getInfo(Arrays.asList(args).subList(1,args.length));
+        for (Iterator<Map.Entry<String, String>> i = m.entrySet().iterator(); i.hasNext(); ) {
+            Map.Entry<String,String> e = i.next();
+            System.out.println("KEY: "+e.getKey());
+            System.out.println("VAL: "+e.getValue());
+        }
+    }
+
+    public static void listenForEvents(String[] args) throws IOException {
+        // Usage: listen [circ|stream|orconn|bw|newdesc|info|notice|warn|error]*
+        TorControlConnection conn = getConnection(args, false);
+        ArrayList<String> lst = new ArrayList<String>();
+        for (int i = 1; i < args.length; ++i) {
+            lst.add(args[i]);
+        }
+        conn.setEventHandler(
+            new DebuggingEventHandler(new PrintWriter(System.out, true)));
+        conn.setEvents(lst);
+    }
+
+    public static void signal(String[] args) throws IOException {
+        // Usage signal [reload|shutdown|dump|debug|halt]
+        TorControlConnection conn = getConnection(args, false);
+        // distinguish shutdown signal from other signals
+        if ("SHUTDOWN".equalsIgnoreCase(args[1])
+        		|| "HALT".equalsIgnoreCase(args[1])) {
+        	conn.shutdownTor(args[1].toUpperCase());
+        } else {
+        	conn.signal(args[1].toUpperCase());
+        }
+    }
+
+    public static void authDemo(String[] args) throws IOException {
+
+        PasswordDigest pwd = PasswordDigest.generateDigest();
+        Socket s = new Socket("127.0.0.1", 9100);
+        TorControlConnection conn = new TorControlConnection(s);
+        conn.launchThread(true);
+        conn.authenticate(new byte[0]);
+
+        conn.setConf("HashedControlPassword", pwd.getHashedPassword());
+
+        s = new Socket("127.0.0.1", 9100);
+        conn = new TorControlConnection(s);
+        conn.launchThread(true);
+        conn.authenticate(pwd.getSecret());
+    }
+
+}
+

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

@@ -8,7 +8,7 @@ import org.briarproject.bramble.lifecycle.LifecycleModule;
 import org.briarproject.bramble.plugin.PluginModule;
 import org.briarproject.bramble.properties.PropertiesModule;
 import org.briarproject.bramble.reporting.ReportingModule;
-import org.briarproject.bramble.sync.SyncModule;
+import org.briarproject.bramble.sync.validation.ValidationModule;
 import org.briarproject.bramble.system.SystemModule;
 import org.briarproject.bramble.transport.TransportModule;
 import org.briarproject.bramble.versioning.VersioningModule;
@@ -31,11 +31,11 @@ public interface BrambleCoreEagerSingletons {
 
 	void inject(ReportingModule.EagerSingletons init);
 
-	void inject(SyncModule.EagerSingletons init);
-
 	void inject(SystemModule.EagerSingletons init);
 
 	void inject(TransportModule.EagerSingletons init);
 
+	void inject(ValidationModule.EagerSingletons init);
+
 	void inject(VersioningModule.EagerSingletons init);
 }

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

@@ -19,6 +19,7 @@ import org.briarproject.bramble.reporting.ReportingModule;
 import org.briarproject.bramble.settings.SettingsModule;
 import org.briarproject.bramble.socks.SocksModule;
 import org.briarproject.bramble.sync.SyncModule;
+import org.briarproject.bramble.sync.validation.ValidationModule;
 import org.briarproject.bramble.system.SystemModule;
 import org.briarproject.bramble.transport.TransportModule;
 import org.briarproject.bramble.versioning.VersioningModule;
@@ -47,6 +48,7 @@ import dagger.Module;
 		SyncModule.class,
 		SystemModule.class,
 		TransportModule.class,
+		ValidationModule.class,
 		VersioningModule.class
 })
 public class BrambleCoreModule {
@@ -60,9 +62,9 @@ public class BrambleCoreModule {
 		c.inject(new PluginModule.EagerSingletons());
 		c.inject(new PropertiesModule.EagerSingletons());
 		c.inject(new ReportingModule.EagerSingletons());
-		c.inject(new SyncModule.EagerSingletons());
 		c.inject(new SystemModule.EagerSingletons());
 		c.inject(new TransportModule.EagerSingletons());
+		c.inject(new ValidationModule.EagerSingletons());
 		c.inject(new VersioningModule.EagerSingletons());
 	}
 }

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

@@ -159,7 +159,8 @@ class AccountManagerImpl implements AccountManager {
 	@Override
 	public boolean createAccount(String name, String password) {
 		synchronized (stateChangeLock) {
-			// TODO don't allow creating another account if one already exists
+			if (hasDatabaseKey())
+				throw new AssertionError("Already have a database key");
 			LocalAuthor localAuthor = identityManager.createLocalAuthor(name);
 			identityManager.registerLocalAuthor(localAuthor);
 			SecretKey key = crypto.generateSecretKey();
@@ -182,6 +183,7 @@ class AccountManagerImpl implements AccountManager {
 			LOG.info("Deleting account");
 			IoUtils.deleteFileOrDir(databaseConfig.getDatabaseKeyDirectory());
 			IoUtils.deleteFileOrDir(databaseConfig.getDatabaseDirectory());
+			databaseKey = null;
 		}
 	}
 

bramble-core/src/main/java/org/briarproject/bramble/battery/DefaultBatteryManagerModule.java

@@ -0,0 +1,19 @@
+package org.briarproject.bramble.battery;
+
+import org.briarproject.bramble.api.battery.BatteryManager;
+
+import dagger.Module;
+import dagger.Provides;
+
+/**
+ * Provides a default implementation of {@link BatteryManager} for systems
+ * without batteries.
+ */
+@Module
+public class DefaultBatteryManagerModule {
+
+	@Provides
+	BatteryManager provideBatteryManager() {
+		return () -> false;
+	}
+}

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

@@ -82,13 +82,7 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public void addLocalMessage(Message m, BdfDictionary metadata,
 			boolean shared) throws DbException, FormatException {
-		Transaction txn = db.startTransaction(false);
-		try {
-			addLocalMessage(txn, m, metadata, shared);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
+		db.transaction(false, txn -> addLocalMessage(txn, m, metadata, shared));
 	}
 
 	@Override
@@ -113,15 +107,7 @@ class ClientHelperImpl implements ClientHelper {
 
 	@Override
 	public Message getMessage(MessageId m) throws DbException {
-		Message message;
-		Transaction txn = db.startTransaction(true);
-		try {
-			message = getMessage(txn, m);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return message;
+		return db.transactionWithResult(true, txn -> getMessage(txn, m));
 	}
 
 	@Override
@@ -132,15 +118,7 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public BdfList getMessageAsList(MessageId m) throws DbException,
 			FormatException {
-		BdfList list;
-		Transaction txn = db.startTransaction(true);
-		try {
-			list = getMessageAsList(txn, m);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return list;
+		return db.transactionWithResult(true, txn -> getMessageAsList(txn, m));
 	}
 
 	@Override
@@ -152,15 +130,8 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public BdfDictionary getGroupMetadataAsDictionary(GroupId g)
 			throws DbException, FormatException {
-		BdfDictionary dictionary;
-		Transaction txn = db.startTransaction(true);
-		try {
-			dictionary = getGroupMetadataAsDictionary(txn, g);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return dictionary;
+		return db.transactionWithResult(true, txn ->
+				getGroupMetadataAsDictionary(txn, g));
 	}
 
 	@Override
@@ -173,15 +144,8 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public BdfDictionary getMessageMetadataAsDictionary(MessageId m)
 			throws DbException, FormatException {
-		BdfDictionary dictionary;
-		Transaction txn = db.startTransaction(true);
-		try {
-			dictionary = getMessageMetadataAsDictionary(txn, m);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return dictionary;
+		return db.transactionWithResult(true, txn ->
+				getMessageMetadataAsDictionary(txn, m));
 	}
 
 	@Override
@@ -194,15 +158,8 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public Map<MessageId, BdfDictionary> getMessageMetadataAsDictionary(
 			GroupId g) throws DbException, FormatException {
-		Map<MessageId, BdfDictionary> map;
-		Transaction txn = db.startTransaction(true);
-		try {
-			map = getMessageMetadataAsDictionary(txn, g);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return map;
+		return db.transactionWithResult(true, txn ->
+				getMessageMetadataAsDictionary(txn, g));
 	}
 
 	@Override
@@ -219,15 +176,8 @@ class ClientHelperImpl implements ClientHelper {
 	public Map<MessageId, BdfDictionary> getMessageMetadataAsDictionary(
 			GroupId g, BdfDictionary query) throws DbException,
 			FormatException {
-		Map<MessageId, BdfDictionary> map;
-		Transaction txn = db.startTransaction(true);
-		try {
-			map = getMessageMetadataAsDictionary(txn, g, query);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return map;
+		return db.transactionWithResult(true, txn ->
+				getMessageMetadataAsDictionary(txn, g, query));
 	}
 
 	@Override
@@ -245,13 +195,7 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public void mergeGroupMetadata(GroupId g, BdfDictionary metadata)
 			throws DbException, FormatException {
-		Transaction txn = db.startTransaction(false);
-		try {
-			mergeGroupMetadata(txn, g, metadata);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
+		db.transaction(false, txn -> mergeGroupMetadata(txn, g, metadata));
 	}
 
 	@Override
@@ -263,13 +207,7 @@ class ClientHelperImpl implements ClientHelper {
 	@Override
 	public void mergeMessageMetadata(MessageId m, BdfDictionary metadata)
 			throws DbException, FormatException {
-		Transaction txn = db.startTransaction(false);
-		try {
-			mergeMessageMetadata(txn, m, metadata);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
+		db.transaction(false, txn -> mergeMessageMetadata(txn, m, metadata));
 	}
 
 	@Override

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

@@ -2,10 +2,11 @@ package org.briarproject.bramble.contact;
 
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.client.ClientHelper;
-import org.briarproject.bramble.api.contact.ContactExchangeListener;
 import org.briarproject.bramble.api.contact.ContactExchangeTask;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.ContactManager;
+import org.briarproject.bramble.api.contact.event.ContactExchangeFailedEvent;
+import org.briarproject.bramble.api.contact.event.ContactExchangeSucceededEvent;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.data.BdfDictionary;
@@ -13,7 +14,7 @@ import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.db.ContactExistsException;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
-import org.briarproject.bramble.api.db.Transaction;
+import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
@@ -64,6 +65,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	private final ClientHelper clientHelper;
 	private final RecordReaderFactory recordReaderFactory;
 	private final RecordWriterFactory recordWriterFactory;
+	private final EventBus eventBus;
 	private final Clock clock;
 	private final ConnectionManager connectionManager;
 	private final ContactManager contactManager;
@@ -72,7 +74,6 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	private final StreamReaderFactory streamReaderFactory;
 	private final StreamWriterFactory streamWriterFactory;
 
-	private volatile ContactExchangeListener listener;
 	private volatile LocalAuthor localAuthor;
 	private volatile DuplexTransportConnection conn;
 	private volatile TransportId transportId;
@@ -82,8 +83,9 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	@Inject
 	ContactExchangeTaskImpl(DatabaseComponent db, ClientHelper clientHelper,
 			RecordReaderFactory recordReaderFactory,
-			RecordWriterFactory recordWriterFactory, Clock clock,
-			ConnectionManager connectionManager, ContactManager contactManager,
+			RecordWriterFactory recordWriterFactory, EventBus eventBus,
+			Clock clock, ConnectionManager connectionManager,
+			ContactManager contactManager,
 			TransportPropertyManager transportPropertyManager,
 			CryptoComponent crypto, StreamReaderFactory streamReaderFactory,
 			StreamWriterFactory streamWriterFactory) {
@@ -91,6 +93,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		this.clientHelper = clientHelper;
 		this.recordReaderFactory = recordReaderFactory;
 		this.recordWriterFactory = recordWriterFactory;
+		this.eventBus = eventBus;
 		this.clock = clock;
 		this.connectionManager = connectionManager;
 		this.contactManager = contactManager;
@@ -101,11 +104,9 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	}
 
 	@Override
-	public void startExchange(ContactExchangeListener listener,
-			LocalAuthor localAuthor, SecretKey masterSecret,
+	public void startExchange(LocalAuthor localAuthor, SecretKey masterSecret,
 			DuplexTransportConnection conn, TransportId transportId,
 			boolean alice) {
-		this.listener = listener;
 		this.localAuthor = localAuthor;
 		this.conn = conn;
 		this.transportId = transportId;
@@ -124,8 +125,8 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 			out = conn.getWriter().getOutputStream();
 		} catch (IOException e) {
 			logException(LOG, WARNING, e);
-			listener.contactExchangeFailed();
 			tryToClose(conn);
+			eventBus.broadcast(new ContactExchangeFailedEvent());
 			return;
 		}
 
@@ -135,7 +136,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 			localProperties = transportPropertyManager.getLocalProperties();
 		} catch (DbException e) {
 			logException(LOG, WARNING, e);
-			listener.contactExchangeFailed();
+			eventBus.broadcast(new ContactExchangeFailedEvent());
 			tryToClose(conn);
 			return;
 		}
@@ -158,7 +159,8 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 				streamWriterFactory.createContactExchangeStreamWriter(out,
 						alice ? aliceHeaderKey : bobHeaderKey);
 		RecordWriter recordWriter =
-				recordWriterFactory.createRecordWriter(streamWriter.getOutputStream());
+				recordWriterFactory
+						.createRecordWriter(streamWriter.getOutputStream());
 
 		// Derive the nonces to be signed
 		byte[] aliceNonce = crypto.mac(ALICE_NONCE_LABEL, masterSecret,
@@ -196,7 +198,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 			}
 		} catch (IOException e) {
 			logException(LOG, WARNING, e);
-			listener.contactExchangeFailed();
+			eventBus.broadcast(new ContactExchangeFailedEvent());
 			tryToClose(conn);
 			return;
 		}
@@ -204,7 +206,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		// Verify the contact's signature
 		if (!verify(remoteInfo.author, remoteNonce, remoteInfo.signature)) {
 			LOG.warning("Invalid signature");
-			listener.contactExchangeFailed();
+			eventBus.broadcast(new ContactExchangeFailedEvent());
 			tryToClose(conn);
 			return;
 		}
@@ -221,15 +223,17 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 					conn);
 			// Pseudonym exchange succeeded
 			LOG.info("Pseudonym exchange succeeded");
-			listener.contactExchangeSucceeded(remoteInfo.author);
+			eventBus.broadcast(
+					new ContactExchangeSucceededEvent(remoteInfo.author));
 		} catch (ContactExistsException e) {
 			logException(LOG, WARNING, e);
 			tryToClose(conn);
-			listener.duplicateContact(remoteInfo.author);
+			eventBus.broadcast(
+					new ContactExchangeFailedEvent(remoteInfo.author));
 		} catch (DbException e) {
 			logException(LOG, WARNING, e);
 			tryToClose(conn);
-			listener.contactExchangeFailed();
+			eventBus.broadcast(new ContactExchangeFailedEvent());
 		}
 	}
 
@@ -287,19 +291,14 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	private ContactId addContact(Author remoteAuthor, long timestamp,
 			Map<TransportId, TransportProperties> remoteProperties)
 			throws DbException {
-		ContactId contactId;
-		Transaction txn = db.startTransaction(false);
-		try {
-			contactId = contactManager.addContact(txn, remoteAuthor,
+		return db.transactionWithResult(false, txn -> {
+			ContactId contactId = contactManager.addContact(txn, remoteAuthor,
 					localAuthor.getId(), masterSecret, timestamp, alice,
 					true, true);
 			transportPropertyManager.addRemoteProperties(txn, contactId,
 					remoteProperties);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return contactId;
+			return contactId;
+		});
 	}
 
 	private void tryToClose(DuplexTransportConnection conn) {

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

@@ -3,6 +3,8 @@ package org.briarproject.bramble.contact;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.ContactManager;
+import org.briarproject.bramble.api.contact.PendingContact;
+import org.briarproject.bramble.api.contact.PendingContactId;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
@@ -10,29 +12,53 @@ import org.briarproject.bramble.api.db.NoSuchContactException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorId;
+import org.briarproject.bramble.api.identity.AuthorInfo;
+import org.briarproject.bramble.api.identity.IdentityManager;
+import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.transport.KeyManager;
 
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.Random;
 import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.regex.Pattern;
 
+import javax.annotation.Nullable;
 import javax.annotation.concurrent.ThreadSafe;
 import javax.inject.Inject;
 
+import static java.util.Collections.emptyList;
+import static org.briarproject.bramble.api.contact.PendingContact.PendingContactState.WAITING_FOR_CONNECTION;
+import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
+import static org.briarproject.bramble.api.identity.AuthorInfo.Status.OURSELVES;
+import static org.briarproject.bramble.api.identity.AuthorInfo.Status.UNKNOWN;
+import static org.briarproject.bramble.api.identity.AuthorInfo.Status.UNVERIFIED;
+import static org.briarproject.bramble.api.identity.AuthorInfo.Status.VERIFIED;
+import static org.briarproject.bramble.util.StringUtils.toUtf8;
+
 @ThreadSafe
 @NotNullByDefault
 class ContactManagerImpl implements ContactManager {
 
+	private static final int LINK_LENGTH = 64;
+	private static final String REMOTE_CONTACT_LINK =
+			"briar://" + getRandomBase32String(LINK_LENGTH);
+	private static final Pattern LINK_REGEX =
+			Pattern.compile("(briar://)?([a-z2-7]{" + LINK_LENGTH + "})");
+
 	private final DatabaseComponent db;
 	private final KeyManager keyManager;
+	private final IdentityManager identityManager;
 	private final List<ContactHook> hooks;
 
 	@Inject
-	ContactManagerImpl(DatabaseComponent db, KeyManager keyManager) {
+	ContactManagerImpl(DatabaseComponent db, KeyManager keyManager,
+			IdentityManager identityManager) {
 		this.db = db;
 		this.keyManager = keyManager;
+		this.identityManager = identityManager;
 		hooks = new CopyOnWriteArrayList<>();
 	}
 
@@ -65,42 +91,63 @@ class ContactManagerImpl implements ContactManager {
 	public ContactId addContact(Author remote, AuthorId local, SecretKey master,
 			long timestamp, boolean alice, boolean verified, boolean active)
 			throws DbException {
-		ContactId c;
-		Transaction txn = db.startTransaction(false);
-		try {
-			c = addContact(txn, remote, local, master, timestamp, alice,
-					verified, active);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
+		return db.transactionWithResult(false, txn ->
+				addContact(txn, remote, local, master, timestamp, alice,
+						verified, active));
+	}
+
+	@Override
+	public String getRemoteContactLink() {
+		// TODO replace with real implementation
+		return REMOTE_CONTACT_LINK;
+	}
+
+	@SuppressWarnings("SameParameterValue")
+	private static String getRandomBase32String(int length) {
+		Random random = new Random();
+		char[] c = new char[length];
+		for (int i = 0; i < length; i++) {
+			int character = random.nextInt(32);
+			if (character < 26) c[i] = (char) ('a' + character);
+			else c[i] = (char) ('2' + (character - 26));
 		}
-		return c;
+		return new String(c);
+	}
+
+	@Override
+	public boolean isValidRemoteContactLink(String link) {
+		return LINK_REGEX.matcher(link).matches();
+	}
+
+	@Override
+	public PendingContact addRemoteContactRequest(String link, String alias) {
+		// TODO replace with real implementation
+		PendingContactId id = new PendingContactId(link.getBytes());
+		return new PendingContact(id, alias, WAITING_FOR_CONNECTION,
+				System.currentTimeMillis());
+	}
+
+	@Override
+	public Collection<PendingContact> getPendingContacts() {
+		// TODO replace with real implementation
+		return emptyList();
+	}
+
+	@Override
+	public void removePendingContact(PendingContact pendingContact) {
+		// TODO replace with real implementation
 	}
 
 	@Override
 	public Contact getContact(ContactId c) throws DbException {
-		Contact contact;
-		Transaction txn = db.startTransaction(true);
-		try {
-			contact = db.getContact(txn, c);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return contact;
+		return db.transactionWithResult(true, txn -> db.getContact(txn, c));
 	}
 
 	@Override
 	public Contact getContact(AuthorId remoteAuthorId, AuthorId localAuthorId)
 			throws DbException {
-		Transaction txn = db.startTransaction(true);
-		try {
-			Contact c = getContact(txn, remoteAuthorId, localAuthorId);
-			db.commitTransaction(txn);
-			return c;
-		} finally {
-			db.endTransaction(txn);
-		}
+		return db.transactionWithResult(true, txn ->
+				getContact(txn, remoteAuthorId, localAuthorId));
 	}
 
 	@Override
@@ -118,14 +165,8 @@ class ContactManagerImpl implements ContactManager {
 
 	@Override
 	public Collection<Contact> getActiveContacts() throws DbException {
-		Collection<Contact> contacts;
-		Transaction txn = db.startTransaction(true);
-		try {
-			contacts = db.getContacts(txn);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
+		Collection<Contact> contacts =
+				db.transactionWithResult(true, db::getContacts);
 		List<Contact> active = new ArrayList<>(contacts.size());
 		for (Contact c : contacts) if (c.isActive()) active.add(c);
 		return active;
@@ -133,13 +174,7 @@ class ContactManagerImpl implements ContactManager {
 
 	@Override
 	public void removeContact(ContactId c) throws DbException {
-		Transaction txn = db.startTransaction(false);
-		try {
-			removeContact(txn, c);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
+		db.transaction(false, txn -> removeContact(txn, c));
 	}
 
 	@Override
@@ -148,6 +183,23 @@ class ContactManagerImpl implements ContactManager {
 		db.setContactActive(txn, c, active);
 	}
 
+	@Override
+	public void setContactAlias(Transaction txn, ContactId c,
+			@Nullable String alias) throws DbException {
+		if (alias != null) {
+			int aliasLength = toUtf8(alias).length;
+			if (aliasLength == 0 || aliasLength > MAX_AUTHOR_NAME_LENGTH)
+				throw new IllegalArgumentException();
+		}
+		db.setContactAlias(txn, c, alias);
+	}
+
+	@Override
+	public void setContactAlias(ContactId c, @Nullable String alias)
+			throws DbException {
+		db.transaction(false, txn -> setContactAlias(txn, c, alias));
+	}
+
 	@Override
 	public boolean contactExists(Transaction txn, AuthorId remoteAuthorId,
 			AuthorId localAuthorId) throws DbException {
@@ -157,15 +209,8 @@ class ContactManagerImpl implements ContactManager {
 	@Override
 	public boolean contactExists(AuthorId remoteAuthorId,
 			AuthorId localAuthorId) throws DbException {
-		boolean exists;
-		Transaction txn = db.startTransaction(true);
-		try {
-			exists = contactExists(txn, remoteAuthorId, localAuthorId);
-			db.commitTransaction(txn);
-		} finally {
-			db.endTransaction(txn);
-		}
-		return exists;
+		return db.transactionWithResult(true, txn ->
+				contactExists(txn, remoteAuthorId, localAuthorId));
 	}
 
 	@Override
@@ -176,4 +221,23 @@ class ContactManagerImpl implements ContactManager {
 		db.removeContact(txn, c);
 	}
 
+	@Override
+	public AuthorInfo getAuthorInfo(AuthorId a) throws DbException {
+		return db.transactionWithResult(true, txn -> getAuthorInfo(txn, a));
+	}
+
+	@Override
+	public AuthorInfo getAuthorInfo(Transaction txn, AuthorId authorId)
+			throws DbException {
+		LocalAuthor localAuthor = identityManager.getLocalAuthor(txn);
+		if (localAuthor.getId().equals(authorId))
+			return new AuthorInfo(OURSELVES);
+		Collection<Contact> contacts = db.getContactsByAuthorId(txn, authorId);
+		if (contacts.isEmpty()) return new AuthorInfo(UNKNOWN);
+		if (contacts.size() > 1) throw new AssertionError();
+		Contact c = contacts.iterator().next();
+		if (c.isVerified()) return new AuthorInfo(VERIFIED, c.getAlias());
+		else return new AuthorInfo(UNVERIFIED, c.getAlias());
+	}
+
 }

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

@@ -29,6 +29,7 @@ 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.fromUtf8;
 
 @NotThreadSafe
 @NotNullByDefault
@@ -253,7 +254,7 @@ class BdfReaderImpl implements BdfReader {
 		if (length < 0 || length > maxBufferSize) throw new FormatException();
 		if (length == 0) return "";
 		readIntoBuffer(length);
-		return new String(buf, 0, length, "UTF-8");
+		return fromUtf8(buf, 0, length);
 	}
 
 	private int readStringLength() throws IOException {

bramble-core/src/main/java/org/briarproject/bramble/db/Database.java

@@ -22,7 +22,7 @@ import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.sync.MessageStatus;
-import org.briarproject.bramble.api.sync.ValidationManager.State;
+import org.briarproject.bramble.api.sync.validation.MessageState;
 import org.briarproject.bramble.api.transport.KeySet;
 import org.briarproject.bramble.api.transport.KeySetId;
 import org.briarproject.bramble.api.transport.TransportKeys;
@@ -106,7 +106,7 @@ interface Database<T> {
 	 * @param sender the contact from whom the message was received, or null
 	 * if the message was created locally.
 	 */
-	void addMessage(T txn, Message m, State state, boolean shared,
+	void addMessage(T txn, Message m, MessageState state, boolean shared,
 			@Nullable ContactId sender) throws DbException;
 
 	/**
@@ -114,7 +114,7 @@ interface Database<T> {
 	 * in the given state.
 	 */
 	void addMessageDependency(T txn, Message dependent, MessageId dependency,
-			State dependentState) throws DbException;
+			MessageState dependentState) throws DbException;
 
 	/**
 	 * Records that a message has been offered by the given contact.
@@ -310,11 +310,11 @@ interface Database<T> {
 	/**
 	 * Returns the IDs and states of all dependencies of the given message.
 	 * For missing dependencies and dependencies in other groups, the state
-	 * {@link State UNKNOWN} is returned.
+	 * {@link MessageState UNKNOWN} is returned.
 	 * <p/>
 	 * Read-only.
 	 */
-	Map<MessageId, State> getMessageDependencies(T txn, MessageId m)
+	Map<MessageId, MessageState> getMessageDependencies(T txn, MessageId m)
 			throws DbException;
 
 	/**
@@ -324,7 +324,7 @@ interface Database<T> {
 	 * <p/>
 	 * Read-only.
 	 */
-	Map<MessageId, State> getMessageDependents(T txn, MessageId m)
+	Map<MessageId, MessageState> getMessageDependents(T txn, MessageId m)
 			throws DbException;
 
 	/**
@@ -383,7 +383,7 @@ interface Database<T> {
 	 * <p/>
 	 * Read-only.
 	 */
-	State getMessageState(T txn, MessageId m) throws DbException;
+	MessageState getMessageState(T txn, MessageId m) throws DbException;
 
 	/**
 	 * Returns the status of all delivered messages in the given group with
@@ -616,6 +616,12 @@ interface Database<T> {
 	void setContactActive(T txn, ContactId c, boolean active)
 			throws DbException;
 
+	/**
+	 * Sets an alias name for a contact.
+	 */
+	void setContactAlias(T txn, ContactId c, @Nullable String alias)
+			throws DbException;
+
 	/**
 	 * Sets the given group's visibility to the given contact to either
 	 * {@link Visibility VISIBLE} or {@link Visibility SHARED}.
@@ -631,7 +637,8 @@ interface Database<T> {
 	/**
 	 * Sets the validation and delivery state of the given message.
 	 */
-	void setMessageState(T txn, MessageId m, State state) throws DbException;
+	void setMessageState(T txn, MessageId m, MessageState state)
+			throws DbException;
 
 	/**
 	 * Sets the reordering window for the given key set and transport in the

bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseComponentImpl.java

@@ -9,7 +9,9 @@ import org.briarproject.bramble.api.contact.event.ContactVerifiedEvent;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.db.ContactExistsException;
 import org.briarproject.bramble.api.db.DatabaseComponent;
+import org.briarproject.bramble.api.db.DbCallable;
 import org.briarproject.bramble.api.db.DbException;
+import org.briarproject.bramble.api.db.DbRunnable;
 import org.briarproject.bramble.api.db.Metadata;
 import org.briarproject.bramble.api.db.MigrationListener;
 import org.briarproject.bramble.api.db.NoSuchContactException;
@@ -17,6 +19,7 @@ import org.briarproject.bramble.api.db.NoSuchGroupException;
 import org.briarproject.bramble.api.db.NoSuchLocalAuthorException;
 import org.briarproject.bramble.api.db.NoSuchMessageException;
 import org.briarproject.bramble.api.db.NoSuchTransportException;
+import org.briarproject.bramble.api.db.NullableDbCallable;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventBus;
@@ -40,7 +43,6 @@ import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.sync.MessageStatus;
 import org.briarproject.bramble.api.sync.Offer;
 import org.briarproject.bramble.api.sync.Request;
-import org.briarproject.bramble.api.sync.ValidationManager.State;
 import org.briarproject.bramble.api.sync.event.GroupAddedEvent;
 import org.briarproject.bramble.api.sync.event.GroupRemovedEvent;
 import org.briarproject.bramble.api.sync.event.GroupVisibilityUpdatedEvent;
@@ -52,6 +54,7 @@ import org.briarproject.bramble.api.sync.event.MessageToAckEvent;
 import org.briarproject.bramble.api.sync.event.MessageToRequestEvent;
 import org.briarproject.bramble.api.sync.event.MessagesAckedEvent;
 import org.briarproject.bramble.api.sync.event.MessagesSentEvent;
+import org.briarproject.bramble.api.sync.validation.MessageState;
 import org.briarproject.bramble.api.transport.KeySet;
 import org.briarproject.bramble.api.transport.KeySetId;
 import org.briarproject.bramble.api.transport.TransportKeys;
@@ -72,8 +75,8 @@ import javax.inject.Inject;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.api.sync.Group.Visibility.INVISIBLE;
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
-import static org.briarproject.bramble.api.sync.ValidationManager.State.DELIVERED;
-import static org.briarproject.bramble.api.sync.ValidationManager.State.UNKNOWN;
+import static org.briarproject.bramble.api.sync.validation.MessageState.DELIVERED;
+import static org.briarproject.bramble.api.sync.validation.MessageState.UNKNOWN;
 import static org.briarproject.bramble.db.DatabaseConstants.MAX_OFFERED_MESSAGES;
 import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.logException;
@@ -166,6 +169,45 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 			for (Event e : transaction.getEvents()) eventBus.broadcast(e);
 	}
 
+	@Override
+	public <E extends Exception> void transaction(boolean readOnly,
+			DbRunnable<E> task) throws DbException, E {
+		Transaction txn = startTransaction(readOnly);
+		try {
+			task.run(txn);
+			commitTransaction(txn);
+		} finally {
+			endTransaction(txn);
+		}
+	}
+
+	@Override
+	public <R, E extends Exception> R transactionWithResult(boolean readOnly,
+			DbCallable<R, E> task) throws DbException, E {
+		Transaction txn = startTransaction(readOnly);
+		try {
+			R result = task.call(txn);
+			commitTransaction(txn);
+			return result;
+		} finally {
+			endTransaction(txn);
+		}
+	}
+
+	@Override
+	public <R, E extends Exception> R transactionWithNullableResult(
+			boolean readOnly, NullableDbCallable<R, E> task)
+			throws DbException, E {
+		Transaction txn = startTransaction(readOnly);
+		try {
+			R result = task.call(txn);
+			commitTransaction(txn);
+			return result;
+		} finally {
+			endTransaction(txn);
+		}
+	}
+
 	private T unbox(Transaction transaction) {
 		if (transaction.isCommitted()) throw new IllegalStateException();
 		return txnClass.cast(transaction.unbox());
@@ -537,7 +579,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 	}
 
 	@Override
-	public State getMessageState(Transaction transaction, MessageId m)
+	public MessageState getMessageState(Transaction transaction, MessageId m)
 			throws DbException {
 		T txn = unbox(transaction);
 		if (!db.containsMessage(txn, m))
@@ -577,8 +619,8 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 	}
 
 	@Override
-	public Map<MessageId, State> getMessageDependencies(Transaction transaction,
-			MessageId m) throws DbException {
+	public Map<MessageId, MessageState> getMessageDependencies(
+			Transaction transaction, MessageId m) throws DbException {
 		T txn = unbox(transaction);
 		if (!db.containsMessage(txn, m))
 			throw new NoSuchMessageException();
@@ -586,8 +628,8 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 	}
 
 	@Override
-	public Map<MessageId, State> getMessageDependents(Transaction transaction,
-			MessageId m) throws DbException {
+	public Map<MessageId, MessageState> getMessageDependents(
+			Transaction transaction, MessageId m) throws DbException {
 		T txn = unbox(transaction);
 		if (!db.containsMessage(txn, m))
 			throw new NoSuchMessageException();
@@ -832,6 +874,16 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 		transaction.attach(new ContactStatusChangedEvent(c, active));
 	}
 
+	@Override
+	public void setContactAlias(Transaction transaction, ContactId c,
+			@Nullable String alias) throws DbException {
+		if (transaction.isReadOnly()) throw new IllegalArgumentException();
+		T txn = unbox(transaction);
+		if (!db.containsContact(txn, c))
+			throw new NoSuchContactException();
+		db.setContactAlias(txn, c, alias);
+	}
+
 	@Override
 	public void setGroupVisibility(Transaction transaction, ContactId c,
 			GroupId g, Visibility v) throws DbException {
@@ -866,7 +918,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 
 	@Override
 	public void setMessageState(Transaction transaction, MessageId m,
-			State state) throws DbException {
+			MessageState state) throws DbException {
 		if (transaction.isReadOnly()) throw new IllegalArgumentException();
 		T txn = unbox(transaction);
 		if (!db.containsMessage(txn, m))
@@ -883,10 +935,10 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 		T txn = unbox(transaction);
 		if (!db.containsMessage(txn, dependent.getId()))
 			throw new NoSuchMessageException();
-		State dependentState = db.getMessageState(txn, dependent.getId());
+		MessageState dependentState =
+				db.getMessageState(txn, dependent.getId());
 		for (MessageId dependency : dependencies) {
-			db.addMessageDependency(txn, dependent, dependency,
-					dependentState);
+			db.addMessageDependency(txn, dependent, dependency, dependentState);
 		}
 	}
 

bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseConstants.java

@@ -2,6 +2,8 @@ package org.briarproject.bramble.db;
 
 import org.briarproject.bramble.api.settings.Settings;
 
+import static java.util.concurrent.TimeUnit.DAYS;
+
 interface DatabaseConstants {
 
 	/**
@@ -23,4 +25,16 @@ interface DatabaseConstants {
 	 */
 	String SCHEMA_VERSION_KEY = "schemaVersion";
 
+	/**
+	 * The {@link Settings} key under which the time of the last database
+	 * compaction is stored.
+	 */
+	String LAST_COMPACTED_KEY = "lastCompacted";
+
+	/**
+	 * The maximum time between database compactions in milliseconds. When the
+	 * database is opened it will be compacted if more than this amount of time
+	 * has passed since the last compaction.
+	 */
+	long MAX_COMPACTION_INTERVAL_MS = DAYS.toMillis(30);
 }

bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseTypes.java

@@ -0,0 +1,34 @@
+package org.briarproject.bramble.db;
+
+class DatabaseTypes {
+
+	private final String hashType, secretType, binaryType;
+	private final String counterType, stringType;
+
+	public DatabaseTypes(String hashType, String secretType, String binaryType,
+			String counterType, String stringType) {
+		this.hashType = hashType;
+		this.secretType = secretType;
+		this.binaryType = binaryType;
+		this.counterType = counterType;
+		this.stringType = stringType;
+	}
+
+	/**
+	 * Replaces database type placeholders in a statement with the actual types.
+	 * These placeholders are currently supported:
+	 * <li> _HASH
+	 * <li> _SECRET
+	 * <li> _BINARY
+	 * <li> _COUNTER
+	 * <li> _STRING
+	 */
+	String replaceTypes(String s) {
+		s = s.replaceAll("_HASH", hashType);
+		s = s.replaceAll("_SECRET", secretType);
+		s = s.replaceAll("_BINARY", binaryType);
+		s = s.replaceAll("_COUNTER", counterType);
+		s = s.replaceAll("_STRING", stringType);
+		return s;
+	}
+}

bramble-core/src/main/java/org/briarproject/bramble/db/H2Database.java

@@ -13,22 +13,32 @@ import java.io.File;
 import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
+import java.sql.Statement;
 import java.util.Properties;
+import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.db.JdbcUtils.tryToClose;
+
 /**
  * Contains all the H2-specific code for the database.
  */
 @NotNullByDefault
 class H2Database extends JdbcDatabase {
 
+	private static final Logger LOG = getLogger(H2Database.class.getName());
+
 	private static final String HASH_TYPE = "BINARY(32)";
 	private static final String SECRET_TYPE = "BINARY(32)";
 	private static final String BINARY_TYPE = "BINARY";
 	private static final String COUNTER_TYPE = "INT NOT NULL AUTO_INCREMENT";
 	private static final String STRING_TYPE = "VARCHAR";
+	private static final DatabaseTypes dbTypes = new DatabaseTypes(HASH_TYPE,
+			SECRET_TYPE, BINARY_TYPE, COUNTER_TYPE, STRING_TYPE);
 
 	private final DatabaseConfig config;
 	private final String url;
@@ -39,8 +49,7 @@ class H2Database extends JdbcDatabase {
 	@Inject
 	H2Database(DatabaseConfig config, MessageFactory messageFactory,
 			Clock clock) {
-		super(HASH_TYPE, SECRET_TYPE, BINARY_TYPE, COUNTER_TYPE, STRING_TYPE,
-				messageFactory, clock);
+		super(dbTypes, messageFactory, clock);
 		this.config = config;
 		File dir = config.getDatabaseDirectory();
 		String path = new File(dir, "db").getAbsolutePath();
@@ -106,4 +115,22 @@ class H2Database extends JdbcDatabase {
 	String getUrl() {
 		return url;
 	}
+
+	@Override
+	protected void compactAndClose() throws DbException {
+		Connection c = null;
+		Statement s = null;
+		try {
+			c = createConnection();
+			closeAllConnections();
+			s = c.createStatement();
+			s.execute("SHUTDOWN COMPACT");
+			s.close();
+			c.close();
+		} catch (SQLException e) {
+			tryToClose(s, LOG, WARNING);
+			tryToClose(c, LOG, WARNING);
+			throw new DbException(e);
+		}
+	}
 }

bramble-core/src/main/java/org/briarproject/bramble/db/HyperSqlDatabase.java

@@ -14,22 +14,32 @@ import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.SQLException;
 import java.sql.Statement;
+import java.util.logging.Logger;
 
 import javax.annotation.Nullable;
 import javax.inject.Inject;
 
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.db.JdbcUtils.tryToClose;
+
 /**
  * Contains all the HSQLDB-specific code for the database.
  */
 @NotNullByDefault
 class HyperSqlDatabase extends JdbcDatabase {
 
+	private static final Logger LOG =
+			getLogger(HyperSqlDatabase.class.getName());
+
 	private static final String HASH_TYPE = "BINARY(32)";
 	private static final String SECRET_TYPE = "BINARY(32)";
 	private static final String BINARY_TYPE = "BINARY";
 	private static final String COUNTER_TYPE =
 			"INTEGER NOT NULL GENERATED ALWAYS AS IDENTITY(START WITH 1)";
 	private static final String STRING_TYPE = "VARCHAR";
+	private static final DatabaseTypes dbTypes = new DatabaseTypes(HASH_TYPE,
+			SECRET_TYPE, BINARY_TYPE, COUNTER_TYPE, STRING_TYPE);
 
 	private final DatabaseConfig config;
 	private final String url;
@@ -40,8 +50,7 @@ class HyperSqlDatabase extends JdbcDatabase {
 	@Inject
 	HyperSqlDatabase(DatabaseConfig config, MessageFactory messageFactory,
 			Clock clock) {
-		super(HASH_TYPE, SECRET_TYPE, BINARY_TYPE, COUNTER_TYPE, STRING_TYPE,
-				messageFactory, clock);
+		super(dbTypes, messageFactory, clock);
 		this.config = config;
 		File dir = config.getDatabaseDirectory();
 		String path = new File(dir, "db").getAbsolutePath();
@@ -61,20 +70,24 @@ class HyperSqlDatabase extends JdbcDatabase {
 
 	@Override
 	public void close() throws DbException {
+		Connection c = null;
+		Statement s = null;
 		try {
 			super.closeAllConnections();
-			Connection c = createConnection();
-			Statement s = c.createStatement();
+			c = createConnection();
+			s = c.createStatement();
 			s.executeQuery("SHUTDOWN");
 			s.close();
 			c.close();
 		} catch (SQLException e) {
+			tryToClose(s, LOG, WARNING);
+			tryToClose(c, LOG, WARNING);
 			throw new DbException(e);
 		}
 	}
 
 	@Override
-	public long getFreeSpace() throws DbException {
+	public long getFreeSpace() {
 		File dir = config.getDatabaseDirectory();
 		long maxSize = config.getMaxSize();
 		long free = dir.getFreeSpace();
@@ -104,4 +117,22 @@ class HyperSqlDatabase extends JdbcDatabase {
 		String hex = StringUtils.toHexString(key.getBytes());
 		return DriverManager.getConnection(url + ";crypt_key=" + hex);
 	}
+
+	@Override
+	protected void compactAndClose() throws DbException {
+		Connection c = null;
+		Statement s = null;
+		try {
+			super.closeAllConnections();
+			c = createConnection();
+			s = c.createStatement();
+			s.executeQuery("SHUTDOWN COMPACT");
+			s.close();
+			c.close();
+		} catch (SQLException e) {
+			tryToClose(s, LOG, WARNING);
+			tryToClose(c, LOG, WARNING);
+			throw new DbException(e);
+		}
+	}
 }