Use WhisperSystems Curve25519 library.

Add Curve25519 and Ed25519 to performance tests.
Note: Curve25519 is tested using standard ECDH and ECDHC over the Curve25519 curve.
2026-04-19 06:24:34 +02:00 · 2017-12-07 17:06:58 +00:00 · 2017-12-07 16:48:02 +00:00 · 2017-12-07 13:06:37 +00:00 · 2017-12-07 12:17:50 +00:00 · 2017-12-05 17:22:44 +00:00
851 changed files with 30782 additions and 21128 deletions
@@ -9,17 +9,18 @@ Thumbs.db
 .DS_Store
 # Eclipse project files
-#.classpath
+.classpath
-#.project
+.project
 .settings
 # Local configuration file (sdk path, etc)
 local.properties
 # Android Studio
 .idea/*
 !.idea/runConfigurations/
 !.idea/codeStyleSettings.xml
 .gradle
 build/
 *.iml
-.gitignore
+projectFilesBackup/
 src/test/
@@ -0,0 +1,29 @@
 image: registry.gitlab.com/fdroid/ci-images-base:latest
 cache:
  paths:
    - .gradle/wrapper
    - .gradle/caches
 before_script:
  - set -e
  - export GRADLE_USER_HOME=$PWD/.gradle
  # Accept the license for the Android build tools
  - echo y | /opt/android-sdk/tools/bin/sdkmanager "build-tools;26.0.2"
  # Download OpenJDK 6 so we can compile against its standard library
  - JDK_FILE=openjdk-6-jre-headless_6b38-1.13.10-1~deb7u1_amd64.deb
  - if [ ! -d openjdk ]
  - then
  - wget -q http://ftp.uk.debian.org/debian/pool/main/o/openjdk-6/$JDK_FILE
  - dpkg-deb -x $JDK_FILE openjdk
  - fi
  - export JAVA_6_HOME=$PWD/openjdk/usr/lib/jvm/java-6-openjdk-amd64
 test:
  script:
    - ./gradlew test
 after_script:
    # this file changes every time but should not be cached
    - rm -f $GRADLE_USER_HOME/caches/modules-2/modules-2.lock
    - rm -fr $GRADLE_USER_HOME/caches/*/plugin-resolution/
@@ -0,0 +1,28 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests" type="AndroidJUnit" factoryName="Android JUnit">
    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
    <module name="briar-android" />
    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
    <option name="ALTERNATIVE_JRE_PATH" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-android" />
    <option name="ENV_VARIABLES" />
    <option name="PASS_PARENT_ENVS" value="true" />
    <option name="TEST_SEARCH_SCOPE">
      <value defaultName="singleModule" />
    </option>
    <envs />
    <patterns />
    <method>
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-api" run_configuration_type="AndroidJUnit" />
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-core" run_configuration_type="AndroidJUnit" />
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in bramble-j2se" run_configuration_type="AndroidJUnit" />
      <option name="RunConfigurationTask" enabled="true" run_configuration_name="All tests in briar-core" run_configuration_type="AndroidJUnit" />
    </method>
  </configuration>
 </component>
@@ -0,0 +1,23 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in bramble-api" type="AndroidJUnit" factoryName="Android JUnit">
    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
    <module name="bramble-api" />
    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
    <option name="ALTERNATIVE_JRE_PATH" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-api" />
    <option name="ENV_VARIABLES" />
    <option name="PASS_PARENT_ENVS" value="true" />
    <option name="TEST_SEARCH_SCOPE">
      <value defaultName="singleModule" />
    </option>
    <envs />
    <patterns />
    <method />
  </configuration>
 </component>
@@ -0,0 +1,23 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in bramble-core" type="AndroidJUnit" factoryName="Android JUnit">
    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
    <module name="bramble-core" />
    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
    <option name="ALTERNATIVE_JRE_PATH" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-core" />
    <option name="ENV_VARIABLES" />
    <option name="PASS_PARENT_ENVS" value="true" />
    <option name="TEST_SEARCH_SCOPE">
      <value defaultName="singleModule" />
    </option>
    <envs />
    <patterns />
    <method />
  </configuration>
 </component>
@@ -0,0 +1,23 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in bramble-j2se" type="AndroidJUnit" factoryName="Android JUnit">
    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
    <module name="bramble-j2se" />
    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
    <option name="ALTERNATIVE_JRE_PATH" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
    <option name="VM_PARAMETERS" value="-ea -Djava.library.path=libs" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/bramble-j2se" />
    <option name="ENV_VARIABLES" />
    <option name="PASS_PARENT_ENVS" value="true" />
    <option name="TEST_SEARCH_SCOPE">
      <value defaultName="singleModule" />
    </option>
    <envs />
    <patterns />
    <method />
  </configuration>
 </component>
@@ -0,0 +1,23 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in briar-android" type="AndroidJUnit" factoryName="Android JUnit">
    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
    <module name="briar-android" />
    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
    <option name="ALTERNATIVE_JRE_PATH" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$PROJECT_DIR$/briar-android" />
    <option name="ENV_VARIABLES" />
    <option name="PASS_PARENT_ENVS" value="true" />
    <option name="TEST_SEARCH_SCOPE">
      <value defaultName="singleModule" />
    </option>
    <envs />
    <patterns />
    <method />
  </configuration>
 </component>
@@ -0,0 +1,23 @@
 <component name="ProjectRunConfigurationManager">
  <configuration default="false" name="All tests in briar-core" type="AndroidJUnit" factoryName="Android JUnit">
    <extension name="coverage" enabled="false" merge="false" sample_coverage="true" runner="idea" />
    <module name="briar-core" />
    <option name="ALTERNATIVE_JRE_PATH_ENABLED" value="false" />
    <option name="ALTERNATIVE_JRE_PATH" />
    <option name="PACKAGE_NAME" value="" />
    <option name="MAIN_CLASS_NAME" value="" />
    <option name="METHOD_NAME" value="" />
    <option name="TEST_OBJECT" value="package" />
    <option name="VM_PARAMETERS" value="-ea" />
    <option name="PARAMETERS" value="" />
    <option name="WORKING_DIRECTORY" value="file://$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>
 </component>
@@ -6,99 +6,91 @@ apply plugin: 'witness'
 apply plugin: 'de.undercouch.download'
 android {
-	compileSdkVersion 23
+	compileSdkVersion 27
-	buildToolsVersion "23.0.3"
+	buildToolsVersion '26.0.2'
 	defaultConfig {
 		minSdkVersion 14
-		targetSdkVersion 22
+		targetSdkVersion 26
-		versionCode 1
+		versionCode 1700
-		versionName "1.0"
+		versionName "0.17.0"
 		consumerProguardFiles 'proguard-rules.txt'
 	}
 	compileOptions {
-		sourceCompatibility JavaVersion.VERSION_1_7
+		sourceCompatibility JavaVersion.VERSION_1_8
-		targetCompatibility JavaVersion.VERSION_1_7
+		targetCompatibility JavaVersion.VERSION_1_8
 	}
 }
 dependencies {
-	compile project(':bramble-core')
+	implementation project(path: ':bramble-core', configuration: 'default')
-	compile fileTree(dir: 'libs', include: ['*.jar'])
+	implementation fileTree(dir: 'libs', include: '*.jar')
-	provided 'javax.annotation:jsr250-api:1.0'
+
 	annotationProcessor 'com.google.dagger:dagger-compiler:2.0.2'
 	compileOnly 'javax.annotation:jsr250-api:1.0'
 }
-def torBinaryDir = 'src/main/res/raw'
+dependencyVerification {
 	verify = [
 			'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
 			'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.guava:guava:18.0:guava-18.0.jar:d664fbfc03d2e5ce9cab2a44fb01f1d0bf9dfebeccc1a473b1f9ea31f79f6f99',
 			'com.h2database:h2:1.4.192:h2-1.4.192.jar:225b22e9857235c46c93861410b60b8c81c10dc8985f4faf188985ba5445126c',
 			'com.madgag.spongycastle:core:1.58.0.0:core-1.58.0.0.jar:199617dd5698c5a9312b898c0a4cec7ce9dd8649d07f65d91629f58229d72728',
 			'javax.annotation:jsr250-api:1.0:jsr250-api-1.0.jar:a1a922d0d9b6d183ed3800dfac01d1e1eb159f0e8c6f94736931c1def54a941f',
 			'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
 			'net.i2p.crypto:eddsa:0.2.0:eddsa-0.2.0.jar:a7cb1b85c16e2f0730b9204106929a1d9aaae1df728adc7041a8b8b605692140',
 			'org.bitlet:weupnp:0.1.4:weupnp-0.1.4.jar:88df7e6504929d00bdb832863761385c68ab92af945b04f0770b126270a444fb',
 			'org.jacoco:org.jacoco.agent:0.7.4.201502262128:org.jacoco.agent-0.7.4.201502262128-runtime.jar:e357a0f1d573c2f702a273992b1b6cb661734f66311854efb3778a888515c5b5',
 			'org.jacoco:org.jacoco.agent:0.7.4.201502262128:org.jacoco.agent-0.7.4.201502262128.jar:47b4bec6df11a1118da3953da8b9fa1e7079d6fec857faa1a3cf912e53a6fd4e',
 			'org.jacoco:org.jacoco.ant:0.7.4.201502262128:org.jacoco.ant-0.7.4.201502262128.jar:013ce2a68ba57a3c59215ae0dec4df3498c078062a38c3b94c841fc14450f283',
 			'org.jacoco:org.jacoco.core:0.7.4.201502262128:org.jacoco.core-0.7.4.201502262128.jar:ec4c74554312fac5116350164786f91b35c9e082fa4ea598bfa42b5db05d7abb',
 			'org.jacoco:org.jacoco.report:0.7.4.201502262128:org.jacoco.report-0.7.4.201502262128.jar:7a3554c605e088e7e323b1084656243f0444fa353e2f2dee1f1a4204eb64ff09',
 			'org.ow2.asm:asm-debug-all:5.0.1:asm-debug-all-5.0.1.jar:4734de5b515a454b0096db6971fb068e5f70e6f10bbee2b3bd2fdfe5d978ed57',
 	]
 }
-task downloadTorGeoIp(type: Download) {
+ext.torBinaryDir = 'src/main/res/raw'
-	src 'https://briarproject.org/build/geoip-2015-12-01.zip'
+ext.torVersion = '0.2.9.12'
-	dest "$torBinaryDir/geoip.zip"
+ext.geoipVersion = '2017-09-06'
 ext.torDownloadUrl = 'https://briarproject.org/build/'
 def torBinaries = [
 		"tor_arm"    : '8ed0b347ffed1d6a4d2fd14495118eb92be83e9cc06e057e15220dc288b31688',
 		"tor_arm_pie": '64403262511c29f462ca5e7c7621bfc3c944898364d1d5ad35a016bb8a034283',
 		"tor_x86"    : '61e014607a2079bcf1646289c67bff6372b1aded6e1d8d83d7791efda9a4d5ab',
 		"tor_x86_pie": '18fbc98356697dd0895836ab46d5c9877d1c539193464f7db1e82a65adaaf288',
 		"geoip"      : 'fe49d3adb86d3c512373101422a017dbb86c85a570524663f09dd8ce143a24f3'
 ]
 def downloadBinary(name) {
 	return tasks.create("downloadBinary${name}", Download) {
 		src "${torDownloadUrl}${name}.zip"
 				.replace('tor_', "tor-${torVersion}-")
 				.replace('geoip', "geoip-${geoipVersion}")
 				.replaceAll('_', '-')
 		dest "${torBinaryDir}/${name}.zip"
 		onlyIfNewer true
 	}
 task downloadTorBinaryArm(type: Download) {
 	src 'https://briarproject.org/build/tor-0.2.7.6-arm.zip'
 	dest "$torBinaryDir/tor_arm.zip"
 	onlyIfNewer true
 }
-task downloadTorBinaryArmPie(type: Download) {
+def verifyBinary(name, chksum) {
-	src 'https://briarproject.org/build/tor-0.2.7.6-arm-pie.zip'
+	return tasks.create([
-	dest "$torBinaryDir/tor_arm_pie.zip"
+			name     : "verifyBinary${name}",
-	onlyIfNewer true
+			type     : Verify,
-}
+			dependsOn: downloadBinary(name)]) {
-
+		src "${torBinaryDir}/${name}.zip"
 task downloadTorBinaryX86(type: Download) {
 	src 'https://briarproject.org/build/tor-0.2.7.6-x86.zip'
 	dest "$torBinaryDir/tor_x86.zip"
 	onlyIfNewer true
 }
 task downloadTorBinaryX86Pie(type: Download) {
 	src 'https://briarproject.org/build/tor-0.2.7.6-x86-pie.zip'
 	dest "$torBinaryDir/tor_x86_pie.zip"
 	onlyIfNewer true
 }
 task verifyTorGeoIp(type: Verify, dependsOn: 'downloadTorGeoIp') {
 	src "$torBinaryDir/geoip.zip"
 		algorithm 'SHA-256'
-	checksum '9bcdaf0a7ba0933735328d8ec466c25c25dbb459efc2bce9e55c774eabea5162'
+		checksum chksum
 	}
 task verifyTorBinaryArm(type: Verify, dependsOn: 'downloadTorBinaryArm') {
 	src "$torBinaryDir/tor_arm.zip"
 	algorithm 'SHA-256'
 	checksum '83272962eda701cd5d74d2418651c4ff0f0b1dff51f558a292d1a1c42bf12146'
 }
 task verifyTorBinaryArmPie(type: Verify, dependsOn: 'downloadTorBinaryArmPie') {
 	src "$torBinaryDir/tor_arm_pie.zip"
 	algorithm 'SHA-256'
 	checksum 'd0300d1e45de11ebb24ed62b9c492be9c2e88590b7822195ab38c7a76ffcf646'
 }
 task verifyTorBinaryX86(type: Verify, dependsOn: 'downloadTorBinaryX86') {
 	src "$torBinaryDir/tor_x86.zip"
 	algorithm 'SHA-256'
 	checksum 'b8813d97b01ee1b9c9a4233c1b9bbe9f9f6b494ae6f9cbd84de8a3911911615e'
 }
 task verifyTorBinaryX86Pie(type: Verify, dependsOn: 'downloadTorBinaryX86Pie') {
 	src "$torBinaryDir/tor_x86_pie.zip"
 	algorithm 'SHA-256'
 	checksum '9c66e765aa196dc089951a1b2140cc8290305c2fcbf365121f99e01a233baf4e'
 }
 project.afterEvaluate {
-	preBuild.dependsOn {
+	torBinaries.every { key, value ->
-		[
+		preBuild.dependsOn.add(verifyBinary(key, value))
 				'verifyTorGeoIp',
 				'verifyTorBinaryArm',
 				'verifyTorBinaryArmPie',
 				'verifyTorBinaryX86',
 				'verifyTorBinaryX86Pie'
 		]
 	}
 }
@@ -8,6 +8,8 @@
 -dontwarn dagger.**
 -dontnote dagger.**
 -keep class net.i2p.crypto.eddsa.** { *; }
 -dontwarn sun.misc.Unsafe
 -dontnote com.google.common.**
@@ -11,8 +11,6 @@
 	<uses-permission android:name="android.permission.INTERNET"/>
 	<uses-permission android:name="android.permission.READ_LOGS"/>
 	<uses-permission android:name="android.permission.WAKE_LOCK"/>
 	<!-- Since API 23, this is needed to add contacts via Bluetooth -->
 	<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
 	<application
 		android:allowBackup="false"
@@ -39,13 +39,13 @@ public class AndroidPluginModule {
 			EventBus eventBus) {
 		Context appContext = app.getApplicationContext();
 		DuplexPluginFactory bluetooth = new DroidtoothPluginFactory(ioExecutor,
-				androidExecutor, appContext, random, backoffFactory);
+				androidExecutor, appContext, random, eventBus, backoffFactory);
 		DuplexPluginFactory tor = new TorPluginFactory(ioExecutor, appContext,
 				locationUtils, reporter, eventBus, torSocketFactory,
 				backoffFactory);
 		DuplexPluginFactory lan = new AndroidLanTcpPluginFactory(ioExecutor,
 				backoffFactory, appContext);
-		final Collection<DuplexPluginFactory> duplex =
+		Collection<DuplexPluginFactory> duplex =
 				Arrays.asList(bluetooth, tor, lan);
 		@NotNullByDefault
 		PluginConfig pluginConfig = new PluginConfig() {
@@ -11,17 +11,21 @@ import android.content.IntentFilter;
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.crypto.PseudoRandom;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventListener;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.plugin.Backoff;
 import org.briarproject.bramble.api.plugin.PluginException;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginCallback;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.plugin.event.DisableBluetoothEvent;
 import org.briarproject.bramble.api.plugin.event.EnableBluetoothEvent;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.system.AndroidExecutor;
 import org.briarproject.bramble.util.AndroidUtils;
@@ -29,23 +33,14 @@ import org.briarproject.bramble.util.StringUtils;
 import java.io.Closeable;
 import java.io.IOException;
 import java.io.InputStream;
 import java.security.SecureRandom;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.UUID;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CompletionService;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorCompletionService;
 import java.util.concurrent.Future;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.logging.Logger;
@@ -60,12 +55,11 @@ 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.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.api.keyagreement.KeyAgreementConstants.TRANSPORT_ID_BLUETOOTH;
 import static org.briarproject.bramble.api.plugin.BluetoothConstants.ID;
 import static org.briarproject.bramble.api.plugin.BluetoothConstants.PREF_BT_ENABLE;
 import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_ADDRESS;
 import static org.briarproject.bramble.api.plugin.BluetoothConstants.PROP_UUID;
 import static org.briarproject.bramble.api.plugin.BluetoothConstants.UUID_BYTES;
@@ -73,14 +67,10 @@ import static org.briarproject.bramble.util.PrivacyUtils.scrubMacAddress;
@MethodsNotNullByDefault
@ParametersNotNullByDefault
-class DroidtoothPlugin implements DuplexPlugin {
+class DroidtoothPlugin implements DuplexPlugin, EventListener {
 	private static final Logger LOG =
 			Logger.getLogger(DroidtoothPlugin.class.getName());
 	private static final String FOUND =
 			"android.bluetooth.device.action.FOUND";
 	private static final String DISCOVERY_FINISHED =
 			"android.bluetooth.adapter.action.DISCOVERY_FINISHED";
 	private final Executor ioExecutor;
 	private final AndroidExecutor androidExecutor;
@@ -128,27 +118,23 @@ class DroidtoothPlugin implements DuplexPlugin {
 	}
 	@Override
-	public boolean start() throws IOException {
+	public void start() throws PluginException {
 		if (used.getAndSet(true)) throw new IllegalStateException();
 		// BluetoothAdapter.getDefaultAdapter() must be called on a thread
 		// with a message queue, so submit it to the AndroidExecutor
 		try {
 			adapter = androidExecutor.runOnBackgroundThread(
-					new Callable<BluetoothAdapter>() {
+					BluetoothAdapter::getDefaultAdapter).get();
 						@Override
 						public BluetoothAdapter call() throws Exception {
 							return BluetoothAdapter.getDefaultAdapter();
 						}
 					}).get();
 		} catch (InterruptedException e) {
 			Thread.currentThread().interrupt();
-			throw new IOException("Interrupted while getting BluetoothAdapter");
+			LOG.warning("Interrupted while getting BluetoothAdapter");
 			throw new PluginException(e);
 		} catch (ExecutionException e) {
-			throw new IOException(e);
+			throw new PluginException(e);
 		}
 		if (adapter == null) {
 			LOG.info("Bluetooth is not supported");
-			return false;
+			throw new PluginException();
 		}
 		running = true;
 		// Listen for changes to the Bluetooth state
@@ -162,21 +148,16 @@ class DroidtoothPlugin implements DuplexPlugin {
 			bind();
 		} else {
 			// Enable Bluetooth if settings allow
-			if (callback.getSettings().getBoolean("enable", false)) {
+			if (callback.getSettings().getBoolean(PREF_BT_ENABLE, false)) {
-				wasEnabledByUs = true;
+				enableAdapter();
 				if (adapter.enable()) LOG.info("Enabling Bluetooth");
 				else LOG.info("Could not enable Bluetooth");
 			} else {
 				LOG.info("Not enabling Bluetooth");
 			}
 		}
 		return true;
 	}
 	private void bind() {
-		ioExecutor.execute(new Runnable() {
+		ioExecutor.execute(() -> {
 			@Override
 			public void run() {
 			if (!isRunning()) return;
 			String address = AndroidUtils.getBluetoothAddress(appContext,
 					adapter);
@@ -194,8 +175,7 @@ class DroidtoothPlugin implements DuplexPlugin {
 				ss = adapter.listenUsingInsecureRfcommWithServiceRecord(
 						"RFCOMM", getUuid());
 			} catch (IOException e) {
-					if (LOG.isLoggable(WARNING))
+				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 						LOG.log(WARNING, e.toString(), e);
 				return;
 			}
 			if (!isRunning()) {
@@ -207,7 +187,6 @@ class DroidtoothPlugin implements DuplexPlugin {
 			backoff.reset();
 			callback.transportEnabled();
 			acceptContactConnections();
 			}
 		});
 	}
@@ -257,13 +236,27 @@ class DroidtoothPlugin implements DuplexPlugin {
 		return new DroidtoothTransportConnection(this, s);
 	}
 	private void enableAdapter() {
 		if (adapter != null && !adapter.isEnabled()) {
 			if (adapter.enable()) {
 				LOG.info("Enabling Bluetooth");
 				wasEnabledByUs = true;
 			} else {
 				LOG.info("Could not enable Bluetooth");
 			}
 		}
 	}
 	@Override
 	public void stop() {
 		running = false;
 		if (receiver != null) appContext.unregisterReceiver(receiver);
 		tryToClose(socket);
-		// Disable Bluetooth if we enabled it and it's still enabled
+		disableAdapter();
-		if (wasEnabledByUs && adapter.isEnabled()) {
+	}
 	private void disableAdapter() {
 		if (adapter != null && adapter.isEnabled() && wasEnabledByUs) {
 			if (adapter.disable()) LOG.info("Disabling Bluetooth");
 			else LOG.info("Could not disable Bluetooth");
 		}
@@ -292,22 +285,19 @@ class DroidtoothPlugin implements DuplexPlugin {
 		Map<ContactId, TransportProperties> remote =
 				callback.getRemoteProperties();
 		for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
-			final ContactId c = e.getKey();
+			ContactId c = e.getKey();
 			if (connected.contains(c)) continue;
-			final String address = e.getValue().get(PROP_ADDRESS);
+			String address = e.getValue().get(PROP_ADDRESS);
 			if (StringUtils.isNullOrEmpty(address)) continue;
-			final String uuid = e.getValue().get(PROP_UUID);
+			String uuid = e.getValue().get(PROP_UUID);
 			if (StringUtils.isNullOrEmpty(uuid)) continue;
-			ioExecutor.execute(new Runnable() {
+			ioExecutor.execute(() -> {
 				@Override
 				public void run() {
 				if (!running) return;
 				BluetoothSocket s = connect(address, uuid);
 				if (s != null) {
 					backoff.reset();
 					callback.outgoingConnectionCreated(c, wrapSocket(s));
 				}
 				}
 			});
 		}
 	}
@@ -361,8 +351,7 @@ class DroidtoothPlugin implements DuplexPlugin {
 	@Override
 	public DuplexTransportConnection createConnection(ContactId c) {
 		if (!isRunning()) return null;
-		TransportProperties p = callback.getRemoteProperties().get(c);
+		TransportProperties p = callback.getRemoteProperties(c);
 		if (p == null) return null;
 		String address = p.get(PROP_ADDRESS);
 		if (StringUtils.isNullOrEmpty(address)) return null;
 		String uuid = p.get(PROP_UUID);
@@ -372,90 +361,6 @@ class DroidtoothPlugin implements DuplexPlugin {
 		return new DroidtoothTransportConnection(this, s);
 	}
 	@Override
 	public boolean supportsInvitations() {
 		return true;
 	}
 	@Override
 	public DuplexTransportConnection createInvitationConnection(PseudoRandom r,
 			long timeout, boolean alice) {
 		if (!isRunning()) return null;
 		// Use the invitation codes to generate the UUID
 		byte[] b = r.nextBytes(UUID_BYTES);
 		UUID uuid = UUID.nameUUIDFromBytes(b);
 		if (LOG.isLoggable(INFO)) LOG.info("Invitation UUID " + uuid);
 		// Bind a server socket for receiving invitation connections
 		BluetoothServerSocket ss;
 		try {
 			ss = adapter.listenUsingInsecureRfcommWithServiceRecord(
 					"RFCOMM", uuid);
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			return null;
 		}
 		// Create the background tasks
 		CompletionService<BluetoothSocket> complete =
 				new ExecutorCompletionService<>(ioExecutor);
 		List<Future<BluetoothSocket>> futures = new ArrayList<>();
 		if (alice) {
 			// Return the first connected socket
 			futures.add(complete.submit(new ListeningTask(ss)));
 			futures.add(complete.submit(new DiscoveryTask(uuid.toString())));
 		} else {
 			// Return the first socket with readable data
 			futures.add(complete.submit(new ReadableTask(
 					new ListeningTask(ss))));
 			futures.add(complete.submit(new ReadableTask(
 					new DiscoveryTask(uuid.toString()))));
 		}
 		BluetoothSocket chosen = null;
 		try {
 			Future<BluetoothSocket> f = complete.poll(timeout, MILLISECONDS);
 			if (f == null) return null; // No task completed within the timeout
 			chosen = f.get();
 			return new DroidtoothTransportConnection(this, chosen);
 		} catch (InterruptedException e) {
 			LOG.info("Interrupted while exchanging invitations");
 			Thread.currentThread().interrupt();
 			return null;
 		} catch (ExecutionException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			return null;
 		} finally {
 			// Closing the socket will terminate the listener task
 			tryToClose(ss);
 			closeSockets(futures, chosen);
 		}
 	}
 	private void closeSockets(final List<Future<BluetoothSocket>> futures,
 			@Nullable final BluetoothSocket chosen) {
 		ioExecutor.execute(new Runnable() {
 			@Override
 			public void run() {
 				for (Future<BluetoothSocket> f : futures) {
 					try {
 						if (f.cancel(true)) {
 							LOG.info("Cancelled task");
 						} else {
 							BluetoothSocket s = f.get();
 							if (s != null && s != chosen) {
 								LOG.info("Closing unwanted socket");
 								s.close();
 							}
 						}
 					} catch (InterruptedException e) {
 						LOG.info("Interrupted while closing sockets");
 						return;
 					} catch (ExecutionException | IOException e) {
 						if (LOG.isLoggable(INFO)) LOG.info(e.toString());
 					}
 				}
 			}
 		});
 	}
 	@Override
 	public boolean supportsKeyAgreement() {
 		return true;
@@ -470,7 +375,7 @@ class DroidtoothPlugin implements DuplexPlugin {
 		// No truncation necessary because COMMIT_LENGTH = 16
 		UUID uuid = UUID.nameUUIDFromBytes(commitment);
 		if (LOG.isLoggable(INFO)) LOG.info("Key agreement UUID " + uuid);
-		// Bind a server socket for receiving invitation connections
+		// Bind a server socket for receiving key agreement connections
 		BluetoothServerSocket ss;
 		try {
 			ss = adapter.listenUsingInsecureRfcommWithServiceRecord(
@@ -511,6 +416,23 @@ class DroidtoothPlugin implements DuplexPlugin {
 		return StringUtils.macToString(mac);
 	}
 	@Override
 	public void eventOccurred(Event e) {
 		if (e instanceof EnableBluetoothEvent) {
 			enableAdapterAsync();
 		} else if (e instanceof DisableBluetoothEvent) {
 			disableAdapterAsync();
 		}
 	}
 	private void enableAdapterAsync() {
 		ioExecutor.execute(this::enableAdapter);
 	}
 	private void disableAdapterAsync() {
 		ioExecutor.execute(this::disableAdapter);
 	}
 	private class BluetoothStateReceiver extends BroadcastReceiver {
 		@Override
@@ -534,115 +456,6 @@ class DroidtoothPlugin implements DuplexPlugin {
 		}
 	}
 	private class DiscoveryTask implements Callable<BluetoothSocket> {
 		private final String uuid;
 		private DiscoveryTask(String uuid) {
 			this.uuid = uuid;
 		}
 		@Override
 		public BluetoothSocket call() throws Exception {
 			// Repeat discovery until we connect or get interrupted
 			while (true) {
 				// Discover nearby devices
 				LOG.info("Discovering nearby devices");
 				List<String> addresses = discoverDevices();
 				if (addresses.isEmpty()) {
 					LOG.info("No devices discovered");
 					continue;
 				}
 				// Connect to any device with the right UUID
 				for (String address : addresses) {
 					BluetoothSocket s = connect(address, uuid);
 					if (s != null) {
 						LOG.info("Outgoing connection");
 						return s;
 					}
 				}
 			}
 		}
 		private List<String> discoverDevices() throws InterruptedException {
 			IntentFilter filter = new IntentFilter();
 			filter.addAction(FOUND);
 			filter.addAction(DISCOVERY_FINISHED);
 			DiscoveryReceiver disco = new DiscoveryReceiver();
 			appContext.registerReceiver(disco, filter);
 			LOG.info("Starting discovery");
 			adapter.startDiscovery();
 			return disco.waitForAddresses();
 		}
 	}
 	private static class DiscoveryReceiver extends BroadcastReceiver {
 		private final CountDownLatch finished = new CountDownLatch(1);
 		private final List<String> addresses = new CopyOnWriteArrayList<>();
 		@Override
 		public void onReceive(Context ctx, Intent intent) {
 			String action = intent.getAction();
 			if (action.equals(DISCOVERY_FINISHED)) {
 				LOG.info("Discovery finished");
 				ctx.unregisterReceiver(this);
 				finished.countDown();
 			} else if (action.equals(FOUND)) {
 				BluetoothDevice d = intent.getParcelableExtra(EXTRA_DEVICE);
 				if (LOG.isLoggable(INFO)) {
 					LOG.info("Discovered device: " +
 							scrubMacAddress(d.getAddress()));
 				}
 				addresses.add(d.getAddress());
 			}
 		}
 		private List<String> waitForAddresses() throws InterruptedException {
 			finished.await();
 			List<String> shuffled = new ArrayList<>(addresses);
 			Collections.shuffle(shuffled);
 			return shuffled;
 		}
 	}
 	private static class ListeningTask implements Callable<BluetoothSocket> {
 		private final BluetoothServerSocket serverSocket;
 		private ListeningTask(BluetoothServerSocket serverSocket) {
 			this.serverSocket = serverSocket;
 		}
 		@Override
 		public BluetoothSocket call() throws IOException {
 			BluetoothSocket s = serverSocket.accept();
 			LOG.info("Incoming connection");
 			return s;
 		}
 	}
 	private static class ReadableTask implements Callable<BluetoothSocket> {
 		private final Callable<BluetoothSocket> connectionTask;
 		private ReadableTask(Callable<BluetoothSocket> connectionTask) {
 			this.connectionTask = connectionTask;
 		}
 		@Override
 		public BluetoothSocket call() throws Exception {
 			BluetoothSocket s = connectionTask.call();
 			InputStream in = s.getInputStream();
 			while (in.available() == 0) {
 				LOG.info("Waiting for data");
 				Thread.sleep(1000);
 			}
 			LOG.info("Data available");
 			return s;
 		}
 	}
 	private class BluetoothKeyAgreementListener extends KeyAgreementListener {
 		private final BluetoothServerSocket ss;
@@ -655,16 +468,13 @@ class DroidtoothPlugin implements DuplexPlugin {
 		@Override
 		public Callable<KeyAgreementConnection> listen() {
-			return new Callable<KeyAgreementConnection>() {
+			return () -> {
 				@Override
 				public KeyAgreementConnection call() throws IOException {
 				BluetoothSocket s = ss.accept();
 				if (LOG.isLoggable(INFO))
 					LOG.info(ID.getString() + ": Incoming connection");
 				return new KeyAgreementConnection(
 						new DroidtoothTransportConnection(
 								DroidtoothPlugin.this, s), ID);
 				}
 			};
 		}
@@ -2,6 +2,7 @@ package org.briarproject.bramble.plugin.droidtooth;
 import android.content.Context;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Backoff;
 import org.briarproject.bramble.api.plugin.BackoffFactory;
@@ -31,15 +32,18 @@ public class DroidtoothPluginFactory implements DuplexPluginFactory {
 	private final AndroidExecutor androidExecutor;
 	private final Context appContext;
 	private final SecureRandom secureRandom;
 	private final EventBus eventBus;
 	private final BackoffFactory backoffFactory;
 	public DroidtoothPluginFactory(Executor ioExecutor,
 			AndroidExecutor androidExecutor, Context appContext,
-			SecureRandom secureRandom, BackoffFactory backoffFactory) {
+			SecureRandom secureRandom, EventBus eventBus,
 			BackoffFactory backoffFactory) {
 		this.ioExecutor = ioExecutor;
 		this.androidExecutor = androidExecutor;
 		this.appContext = appContext;
 		this.secureRandom = secureRandom;
 		this.eventBus = eventBus;
 		this.backoffFactory = backoffFactory;
 	}
@@ -57,7 +61,10 @@ public class DroidtoothPluginFactory implements DuplexPluginFactory {
 	public DuplexPlugin createPlugin(DuplexPluginCallback callback) {
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		return new DroidtoothPlugin(ioExecutor, androidExecutor, appContext,
+		DroidtoothPlugin plugin = new DroidtoothPlugin(ioExecutor,
-				secureRandom, backoff, callback, MAX_LATENCY);
+				androidExecutor, appContext, secureRandom, backoff, callback,
 				MAX_LATENCY);
 		eventBus.addListener(plugin);
 		return plugin;
 	}
 }
@@ -39,14 +39,13 @@ class AndroidLanTcpPlugin extends LanTcpPlugin {
 	}
 	@Override
-	public boolean start() {
+	public void start() {
 		if (used.getAndSet(true)) throw new IllegalStateException();
 		running = true;
 		// Register to receive network status events
 		networkStateReceiver = new NetworkStateReceiver();
 		IntentFilter filter = new IntentFilter(CONNECTIVITY_ACTION);
 		appContext.registerReceiver(networkStateReceiver, filter);
 		return true;
 	}
 	@Override
@@ -17,7 +17,6 @@ import net.freehaven.tor.control.EventHandler;
 import net.freehaven.tor.control.TorControlConnection;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.crypto.PseudoRandom;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventListener;
@@ -25,6 +24,7 @@ import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.plugin.Backoff;
 import org.briarproject.bramble.api.plugin.PluginException;
 import org.briarproject.bramble.api.plugin.TorConstants;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
@@ -55,6 +55,7 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Scanner;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Executor;
@@ -78,13 +79,19 @@ import static java.util.logging.Level.WARNING;
 import static net.freehaven.tor.control.TorControlCommands.HS_ADDRESS;
 import static net.freehaven.tor.control.TorControlCommands.HS_PRIVKEY;
 import static org.briarproject.bramble.api.plugin.TorConstants.CONTROL_PORT;
 import static org.briarproject.bramble.api.plugin.TorConstants.ID;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_ALWAYS;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_NEVER;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_WIFI;
 import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_PORT;
 import static org.briarproject.bramble.api.plugin.TorConstants.PROP_ONION;
 import static org.briarproject.bramble.util.PrivacyUtils.scrubOnion;
@MethodsNotNullByDefault
@ParametersNotNullByDefault
 class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	private static final String PROP_ONION = "onion";
 	private static final String[] EVENTS = {
 			"CIRC", "ORCONN", "HS_DESC", "NOTICE", "WARN", "ERR"
 	};
@@ -142,7 +149,8 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		cookieFile = new File(torDirectory, ".tor/control_auth_cookie");
 		Object o = appContext.getSystemService(POWER_SERVICE);
 		PowerManager pm = (PowerManager) o;
-		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, "TorPlugin");
+		// This tag will prevent Huawei's powermanager from killing us.
 		wakeLock = pm.newWakeLock(PARTIAL_WAKE_LOCK, "LocationManagerService");
 		wakeLock.setReferenceCounted(false);
 	}
@@ -162,14 +170,18 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	@Override
-	public boolean start() throws IOException {
+	public void start() throws PluginException {
 		if (used.getAndSet(true)) throw new IllegalStateException();
 		// Install or update the assets if necessary
 		if (!assetsAreUpToDate()) installAssets();
 		LOG.info("Starting Tor");
 		// Watch for the auth cookie file being updated
 		try {
 			cookieFile.getParentFile().mkdirs();
 			cookieFile.createNewFile();
 		} catch (IOException e) {
 			throw new PluginException(e);
 		}
 		CountDownLatch latch = new CountDownLatch(1);
 		FileObserver obs = new WriteObserver(cookieFile, latch);
 		obs.startWatching();
@@ -177,19 +189,31 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		String torPath = torFile.getAbsolutePath();
 		String configPath = configFile.getAbsolutePath();
 		String pid = String.valueOf(android.os.Process.myPid());
 		String[] cmd = {torPath, "-f", configPath, OWNER, pid};
 		String[] env = {"HOME=" + torDirectory.getAbsolutePath()};
 		Process torProcess;
 		ProcessBuilder pb =
 				new ProcessBuilder(torPath, "-f", configPath, OWNER, pid);
 		Map<String, String> env = pb.environment();
 		env.put("HOME", torDirectory.getAbsolutePath());
 		pb.directory(torDirectory);
 		try {
-			torProcess = Runtime.getRuntime().exec(cmd, env, torDirectory);
+			torProcess = pb.start();
-		} catch (SecurityException e) {
+		} catch (SecurityException | IOException e) {
-			throw new IOException(e);
+			throw new PluginException(e);
 		}
 		// Log the process's standard output until it detaches
 		if (LOG.isLoggable(INFO)) {
 			Scanner stdout = new Scanner(torProcess.getInputStream());
-			while (stdout.hasNextLine()) LOG.info(stdout.nextLine());
+			Scanner stderr = new Scanner(torProcess.getErrorStream());
 			while (stdout.hasNextLine() || stderr.hasNextLine()){
 				if(stdout.hasNextLine()) {
 					LOG.info(stdout.nextLine());
 				}
 				if(stderr.hasNextLine()){
 					LOG.info(stderr.nextLine());
 				}
 			}
 			stdout.close();
 			stderr.close();
 		}
 		try {
 			// Wait for the process to detach or exit
@@ -197,19 +221,20 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 			if (exit != 0) {
 				if (LOG.isLoggable(WARNING))
 					LOG.warning("Tor exited with value " + exit);
-				return false;
+				throw new PluginException();
 			}
 			// Wait for the auth cookie file to be created/updated
 			if (!latch.await(COOKIE_TIMEOUT, MILLISECONDS)) {
 				LOG.warning("Auth cookie not created");
 				if (LOG.isLoggable(INFO)) listFiles(torDirectory);
-				return false;
+				throw new PluginException();
 			}
 		} catch (InterruptedException e) {
 			LOG.warning("Interrupted while starting Tor");
 			Thread.currentThread().interrupt();
-			return false;
+			throw new PluginException();
 		}
 		try {
 			// Open a control connection and authenticate using the cookie file
 			controlSocket = new Socket("127.0.0.1", CONTROL_PORT);
 			controlConnection = new TorControlConnection(controlSocket);
@@ -227,13 +252,15 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 				LOG.info("Tor has already bootstrapped");
 				connectionStatus.setBootstrapped();
 			}
 		} catch (IOException e) {
 			throw new PluginException(e);
 		}
 		// Register to receive network status events
 		networkStateReceiver = new NetworkStateReceiver();
 		IntentFilter filter = new IntentFilter(CONNECTIVITY_ACTION);
 		appContext.registerReceiver(networkStateReceiver, filter);
 		// Bind a server socket to receive incoming hidden service connections
 		bind();
 		return true;
 	}
 	private boolean assetsAreUpToDate() {
@@ -246,7 +273,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		}
 	}
-	private void installAssets() throws IOException {
+	private void installAssets() throws PluginException {
 		InputStream in = null;
 		OutputStream out = null;
 		try {
@@ -269,7 +296,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		} catch (IOException e) {
 			tryToClose(in);
 			tryToClose(out);
-			throw e;
+			throw new PluginException(e);
 		}
 	}
@@ -343,22 +370,17 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	private void sendDevReports() {
-		ioExecutor.execute(new Runnable() {
+		ioExecutor.execute(() -> {
 			@Override
 			public void run() {
 			// TODO: Trigger this with a TransportEnabledEvent
 			File reportDir = AndroidUtils.getReportDir(appContext);
 			reporter.sendReports(reportDir);
 			}
 		});
 	}
 	private void bind() {
-		ioExecutor.execute(new Runnable() {
+		ioExecutor.execute(() -> {
 			@Override
 			public void run() {
 			// If there's already a port number stored in config, reuse it
-				String portString = callback.getSettings().get("port");
+			String portString = callback.getSettings().get(PREF_TOR_PORT);
 			int port;
 			if (StringUtils.isNullOrEmpty(portString)) port = 0;
 			else port = Integer.parseInt(portString);
@@ -368,8 +390,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 				ss = new ServerSocket();
 				ss.bind(new InetSocketAddress("127.0.0.1", port));
 			} catch (IOException e) {
-					if (LOG.isLoggable(WARNING))
+				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 						LOG.log(WARNING, e.toString(), e);
 				tryToClose(ss);
 				return;
 			}
@@ -379,21 +400,15 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 			}
 			socket = ss;
 			// Store the port number
-				final String localPort = String.valueOf(ss.getLocalPort());
+			String localPort = String.valueOf(ss.getLocalPort());
 			Settings s = new Settings();
-				s.put("port", localPort);
+			s.put(PREF_TOR_PORT, localPort);
 			callback.mergeSettings(s);
 			// Create a hidden service if necessary
-				ioExecutor.execute(new Runnable() {
+			ioExecutor.execute(() -> publishHiddenService(localPort));
 					@Override
 					public void run() {
 						publishHiddenService(localPort);
 					}
 				});
 			backoff.reset();
 			// Accept incoming hidden service connections from Tor
 			acceptContactConnections(ss);
 			}
 		});
 	}
@@ -476,7 +491,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	@Override
-	public void stop() throws IOException {
+	public void stop() throws PluginException {
 		running = false;
 		tryToClose(socket);
 		if (networkStateReceiver != null)
@@ -513,29 +528,33 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	public void poll(Collection<ContactId> connected) {
 		if (!isRunning()) return;
 		backoff.increment();
-		// TODO: Pass properties to connectAndCallBack()
+		Map<ContactId, TransportProperties> remote =
-		for (ContactId c : callback.getRemoteProperties().keySet())
+				callback.getRemoteProperties();
-			if (!connected.contains(c)) connectAndCallBack(c);
+		for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
 			ContactId c = e.getKey();
 			if (!connected.contains(c)) connectAndCallBack(c, e.getValue());
 		}
 	}
-	private void connectAndCallBack(final ContactId c) {
+	private void connectAndCallBack(ContactId c, TransportProperties p) {
-		ioExecutor.execute(new Runnable() {
+		ioExecutor.execute(() -> {
-			@Override
+			if (!isRunning()) return;
-			public void run() {
+			DuplexTransportConnection d = createConnection(p);
 				DuplexTransportConnection d = createConnection(c);
 			if (d != null) {
 				backoff.reset();
 				callback.outgoingConnectionCreated(c, d);
 			}
 			}
 		});
 	}
 	@Override
 	public DuplexTransportConnection createConnection(ContactId c) {
 		if (!isRunning()) return null;
-		TransportProperties p = callback.getRemoteProperties().get(c);
+		return createConnection(callback.getRemoteProperties(c));
-		if (p == null) return null;
+	}
 	@Nullable
 	private DuplexTransportConnection createConnection(TransportProperties p) {
 		String onion = p.get(PROP_ONION);
 		if (StringUtils.isNullOrEmpty(onion)) return null;
 		if (!ONION.matcher(onion).matches()) {
@@ -563,17 +582,6 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		}
 	}
 	@Override
 	public boolean supportsInvitations() {
 		return false;
 	}
 	@Override
 	public DuplexTransportConnection createInvitationConnection(PseudoRandom r,
 			long timeout, boolean alice) {
 		throw new UnsupportedOperationException();
 	}
 	@Override
 	public boolean supportsKeyAgreement() {
 		return false;
@@ -658,7 +666,8 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	@Override
 	public void eventOccurred(Event e) {
 		if (e instanceof SettingsUpdatedEvent) {
-			if (((SettingsUpdatedEvent) e).getNamespace().equals("tor")) {
+			SettingsUpdatedEvent s = (SettingsUpdatedEvent) e;
 			if (s.getNamespace().equals(ID.getString())) {
 				LOG.info("Tor settings updated");
 				updateConnectionStatus();
 			}
@@ -666,9 +675,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	private void updateConnectionStatus() {
-		ioExecutor.execute(new Runnable() {
+		ioExecutor.execute(() -> {
 			@Override
 			public void run() {
 			if (!running) return;
 			Object o = appContext.getSystemService(CONNECTIVITY_SERVICE);
@@ -680,7 +687,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 			boolean blocked = TorNetworkMetadata.isTorProbablyBlocked(
 					country);
 			Settings s = callback.getSettings();
-				boolean useMobileData = s.getBoolean("torOverMobile", true);
+			int network = s.getInt(PREF_TOR_NETWORK, PREF_TOR_NETWORK_ALWAYS);
 			if (LOG.isLoggable(INFO)) {
 				LOG.info("Online: " + online + ", wifi: " + wifi);
@@ -695,7 +702,8 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 				} else if (blocked) {
 					LOG.info("Disabling network, country is blocked");
 					enableNetwork(false);
-					} else if (!wifi && !useMobileData) {
+				} else if (network == PREF_TOR_NETWORK_NEVER
 						|| (network == PREF_TOR_NETWORK_WIFI && !wifi)) {
 					LOG.info("Disabling network due to data setting");
 					enableNetwork(false);
 				} else {
@@ -703,9 +711,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 					enableNetwork(true);
 				}
 			} catch (IOException e) {
-					if (LOG.isLoggable(WARNING))
+				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 						LOG.log(WARNING, e.toString(), e);
 				}
 			}
 		});
 	}
@@ -3,6 +3,7 @@ package org.briarproject.bramble.plugin.tor;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.plugin.duplex.AbstractDuplexTransportConnection;
 import org.briarproject.bramble.util.IoUtils;
 import java.io.IOException;
 import java.io.InputStream;
@@ -21,12 +22,12 @@ class TorTransportConnection extends AbstractDuplexTransportConnection {
 	@Override
 	protected InputStream getInputStream() throws IOException {
-		return socket.getInputStream();
+		return IoUtils.getInputStream(socket);
 	}
 	@Override
 	protected OutputStream getOutputStream() throws IOException {
-		return socket.getOutputStream();
+		return IoUtils.getOutputStream(socket);
 	}
 	@Override
@@ -27,14 +27,11 @@ class AndroidExecutorImpl implements AndroidExecutor {
 	@Inject
 	AndroidExecutorImpl(Application app) {
 		uiHandler = new Handler(app.getApplicationContext().getMainLooper());
-		loop = new Runnable() {
+		loop = () -> {
 			@Override
 			public void run() {
 			Looper.prepare();
 			backgroundHandler = new Handler();
 			startLatch.countDown();
 			Looper.loop();
 			}
 		};
 	}
@@ -0,0 +1,93 @@
 package org.briarproject.bramble.system;
 import android.app.Application;
 import android.bluetooth.BluetoothAdapter;
 import android.bluetooth.BluetoothDevice;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.net.wifi.WifiConfiguration;
 import android.net.wifi.WifiManager;
 import android.os.Build;
 import android.os.Parcel;
 import android.provider.Settings;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.List;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 import static android.content.Context.WIFI_SERVICE;
 import static android.provider.Settings.Secure.ANDROID_ID;
@Immutable
@NotNullByDefault
 class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 	private static final int SEED_LENGTH = 32;
 	private final Context appContext;
 	@Inject
 	AndroidSecureRandomProvider(Application app) {
 		appContext = app.getApplicationContext();
 	}
 	@Override
 	protected void writeToEntropyPool(DataOutputStream out) throws IOException {
 		super.writeToEntropyPool(out);
 		out.writeInt(android.os.Process.myPid());
 		out.writeInt(android.os.Process.myTid());
 		out.writeInt(android.os.Process.myUid());
 		if (Build.FINGERPRINT != null) out.writeUTF(Build.FINGERPRINT);
 		if (Build.SERIAL != null) out.writeUTF(Build.SERIAL);
 		ContentResolver contentResolver = appContext.getContentResolver();
 		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);
 		}
 		BluetoothAdapter bt = BluetoothAdapter.getDefaultAdapter();
 		if (bt != null) {
 			for (BluetoothDevice device : bt.getBondedDevices())
 				parcel.writeParcelable(device, 0);
 		}
 		out.write(parcel.marshall());
 		parcel.recycle();
 	}
 	@Override
 	protected void writeSeed() {
 		super.writeSeed();
 		if (Build.VERSION.SDK_INT >= 16 && Build.VERSION.SDK_INT <= 18)
 			applyOpenSslFix();
 	}
 	// Based on https://android-developers.googleblog.com/2013/08/some-securerandom-thoughts.html
 	private void applyOpenSslFix() {
 		byte[] seed = new LinuxSecureRandomSpi().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);
 			// Mix the output of the Linux PRNG into the OpenSSL PRNG
 			int bytesRead = (Integer) Class.forName(
 					"org.apache.harmony.xnet.provider.jsse.NativeCrypto")
 					.getMethod("RAND_load_file", String.class, long.class)
 					.invoke(null, "/dev/urandom", 1024);
 			if (bytesRead != 1024) throw new IOException();
 		} catch (Exception e) {
 			throw new SecurityException(e);
 		}
 	}
 }
@@ -1,42 +0,0 @@
 package org.briarproject.bramble.system;
 import android.app.Application;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.os.Build;
 import android.provider.Settings;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 import static android.provider.Settings.Secure.ANDROID_ID;
@Immutable
@NotNullByDefault
 class AndroidSeedProvider extends LinuxSeedProvider {
 	private final Context appContext;
 	@Inject
 	AndroidSeedProvider(Application app) {
 		appContext = app.getApplicationContext();
 	}
 	@Override
 	void writeToEntropyPool(DataOutputStream out) throws IOException {
 		out.writeInt(android.os.Process.myPid());
 		out.writeInt(android.os.Process.myTid());
 		out.writeInt(android.os.Process.myUid());
 		if (Build.FINGERPRINT != null) out.writeUTF(Build.FINGERPRINT);
 		if (Build.SERIAL != null) out.writeUTF(Build.SERIAL);
 		ContentResolver contentResolver = appContext.getContentResolver();
 		String id = Settings.Secure.getString(contentResolver, ANDROID_ID);
 		if (id != null) out.writeUTF(id);
 		super.writeToEntropyPool(out);
 	}
 }
@@ -4,7 +4,7 @@ import android.app.Application;
 import org.briarproject.bramble.api.system.AndroidExecutor;
 import org.briarproject.bramble.api.system.LocationUtils;
-import org.briarproject.bramble.api.system.SeedProvider;
+import org.briarproject.bramble.api.system.SecureRandomProvider;
 import javax.inject.Singleton;
@@ -16,8 +16,8 @@ public class AndroidSystemModule {
 	@Provides
 	@Singleton
-	SeedProvider provideSeedProvider(Application app) {
+	SecureRandomProvider provideSecureRandomProvider(Application app) {
-		return new AndroidSeedProvider(app);
+		return new AndroidSecureRandomProvider(app);
 	}
 	@Provides
@@ -1,22 +1,55 @@
-apply plugin: 'java'
+apply plugin: 'java-library'
-sourceCompatibility = 1.6
+sourceCompatibility = 1.8
-targetCompatibility = 1.6
+targetCompatibility = 1.8
 apply plugin: 'witness'
 dependencies {
-	compile "com.google.dagger:dagger:2.0.2"
+	implementation "com.google.dagger:dagger:2.0.2"
-	compile 'com.google.dagger:dagger-compiler:2.0.2'
+	implementation 'com.google.code.findbugs:jsr305:3.0.2'
-	compile 'com.google.code.findbugs:jsr305:3.0.1'
+
 	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"
 }
 dependencyVerification {
 	verify = [
-			'com.google.dagger:dagger:84c0282ed8be73a29e0475d639da030b55dee72369e58dd35ae7d4fe6243dcf9',
+			'cglib:cglib:3.2.0:cglib-3.2.0.jar:adb13bab79712ad6bdf1bd59f2a3918018a8016e722e8a357065afb9e6690861',
-			'com.google.dagger:dagger-compiler:b74bc9de063dd4c6400b232231f2ef5056145b8fbecbf5382012007dd1c071b3',
+			'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
-			'javax.inject:javax.inject:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
+			'com.google.dagger:dagger:2.0.2:dagger-2.0.2.jar:84c0282ed8be73a29e0475d639da030b55dee72369e58dd35ae7d4fe6243dcf9',
-			'com.google.dagger:dagger-producers:99ec15e8a0507ba569e7655bc1165ee5e5ca5aa914b3c8f7e2c2458f724edd6b',
+			'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
-			'com.google.guava:guava:d664fbfc03d2e5ce9cab2a44fb01f1d0bf9dfebeccc1a473b1f9ea31f79f6f99',
+			'junit:junit:4.12:junit-4.12.jar:59721f0805e223d84b90677887d9ff567dc534d7c502ca903c0c2b17f05c116a',
-			'com.google.code.findbugs:jsr305:c885ce34249682bc0236b4a7d56efcc12048e6135a5baf7a9cde8ad8cda13fcd'
+			'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.beanshell:bsh:1.3.0:bsh-1.3.0.jar:9b04edc75d19db54f1b4e8b5355e9364384c6cf71eb0a1b9724c159d779879f8',
 			'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.jmock:jmock-junit4:2.8.2:jmock-junit4-2.8.2.jar:f7ee4df4f7bd7b7f1cafad3b99eb74d579f109d5992ff625347352edb55e674c',
 			'org.jmock:jmock-legacy:2.8.2:jmock-legacy-2.8.2.jar:f2b985a5c08a9edb7f37612330c058809da3f6a6d63ce792426ebf8ff0d6d31b',
 			'org.jmock:jmock-testjar:2.8.2:jmock-testjar-2.8.2.jar:8900860f72c474e027cf97fe78dcbf154a1aa7fc62b6845c5fb4e4f3c7bc8760',
 			'org.jmock:jmock:2.8.2:jmock-2.8.2.jar:6c73cb4a2e6dbfb61fd99c9a768539c170ab6568e57846bd60dbf19596b65b16',
 			'org.objenesis:objenesis:2.1:objenesis-2.1.jar:c74330cc6b806c804fd37e74487b4fe5d7c2750c5e15fbc6efa13bdee1bdef80',
 			'org.ow2.asm:asm:5.0.4:asm-5.0.4.jar:896618ed8ae62702521a78bc7be42b7c491a08e6920a15f89a3ecdec31e9a220',
 	]
 }
 // needed to make test output available to bramble-core and briar-core
 configurations {
 	testOutput.extendsFrom(testCompile)
 }
 task jarTest(type: Jar, dependsOn: testClasses) {
 	from sourceSets.test.output
 	classifier = 'test'
 }
 artifacts {
 	testOutput jarTest
 }
 // If a Java 6 JRE is available, check we're not using any Java 7 or 8 APIs
 tasks.withType(JavaCompile) {
 	useJava6StandardLibrary(it)
 }
@@ -1,6 +1,7 @@
 package org.briarproject.bramble.api;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.util.StringUtils;
 import java.util.Arrays;
 import java.util.Comparator;
@@ -53,6 +54,12 @@ public class Bytes implements Comparable<Bytes> {
 		return aBytes.length - bBytes.length;
 	}
 	@Override
 	public String toString() {
 		return getClass().getSimpleName() +
 				"(" + StringUtils.toHexString(getBytes()) + ")";
 	}
 	public static class BytesComparator implements Comparator<Bytes> {
 		@Override
@@ -23,7 +23,7 @@ public class BdfMessageContext {
 	}
 	public BdfMessageContext(BdfDictionary dictionary) {
-		this(dictionary, Collections.<MessageId>emptyList());
+		this(dictionary, Collections.emptyList());
 	}
 	public BdfDictionary getDictionary() {
@@ -12,18 +12,19 @@ public interface ContactGroupFactory {
 	/**
 	 * Creates a group that is not shared with any contacts.
 	 */
-	Group createLocalGroup(ClientId clientId);
+	Group createLocalGroup(ClientId clientId, int clientVersion);
 	/**
 	 * Creates a group for the given client to share with the given contact.
 	 */
-	Group createContactGroup(ClientId clientId, Contact contact);
+	Group createContactGroup(ClientId clientId, int clientVersion,
 			Contact contact);
 	/**
 	 * Creates a group for the given client to share between the given authors
 	 * identified by their AuthorIds.
 	 */
-	Group createContactGroup(ClientId clientId, AuthorId authorId1,
+	Group createContactGroup(ClientId clientId, int clientVersion,
-			AuthorId authorId2);
+			AuthorId authorId1, AuthorId authorId2);
 }
@@ -12,6 +12,32 @@ import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
@NotNullByDefault
 public interface ContactExchangeTask {
 	/**
 	 * The current version of the contact exchange protocol
 	 */
 	int PROTOCOL_VERSION = 0;
 	/**
 	 * Label for deriving Alice's header key from the master secret.
 	 */
 	String ALICE_KEY_LABEL =
 			"org.briarproject.bramble.contact/ALICE_HEADER_KEY";
 	/**
 	 * Label for deriving Bob's header key from the master secret.
 	 */
 	String BOB_KEY_LABEL = "org.briarproject.bramble.contact/BOB_HEADER_KEY";
 	/**
 	 * Label for deriving Alice's key binding nonce from the master secret.
 	 */
 	String ALICE_NONCE_LABEL = "org.briarproject.bramble.contact/ALICE_NONCE";
 	/**
 	 * Label for deriving Bob's key binding nonce from the master secret.
 	 */
 	String BOB_NONCE_LABEL = "org.briarproject.bramble.contact/BOB_NONCE";
 	/**
 	 * Exchanges contact information with a remote peer.
 	 */
@@ -43,6 +43,24 @@ public interface ContactManager {
 	 */
 	Contact getContact(ContactId c) throws DbException;
 	/**
 	 * Returns the contact with the given remoteAuthorId
 	 * that was added by the LocalAuthor with the given localAuthorId
 	 *
 	 * @throws org.briarproject.bramble.api.db.NoSuchContactException
 	 */
 	Contact getContact(AuthorId remoteAuthorId, AuthorId localAuthorId)
 			throws DbException;
 	/**
 	 * Returns the contact with the given remoteAuthorId
 	 * that was added by the LocalAuthor with the given localAuthorId
 	 *
 	 * @throws org.briarproject.bramble.api.db.NoSuchContactException
 	 */
 	Contact getContact(Transaction txn, AuthorId remoteAuthorId,
 			AuthorId localAuthorId) throws DbException;
 	/**
 	 * Returns all active contacts.
 	 */
@@ -1,8 +1,5 @@
 package org.briarproject.bramble.api.crypto;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.transport.TransportKeys;
 import java.security.GeneralSecurityException;
 import java.security.SecureRandom;
@@ -10,8 +7,6 @@ public interface CryptoComponent {
 	SecretKey generateSecretKey();
 	PseudoRandom getPseudoRandom(int seed1, int seed2);
 	SecureRandom getSecureRandom();
 	KeyPair generateAgreementKeyPair();
@@ -22,164 +17,98 @@ public interface CryptoComponent {
 	KeyParser getSignatureKeyParser();
 	KeyPair generateEdKeyPair();
 	KeyParser getEdKeyParser();
 	KeyParser getMessageKeyParser();
 	/** Generates a random invitation code. */
 	int generateBTInvitationCode();
 	/**
-	 * Derives a confirmation code from the given master secret.
+	 * Derives another secret key from the given secret key.
 	 * @param alice whether the code is for use by Alice or Bob.
 	 */
 	int deriveBTConfirmationCode(SecretKey master, boolean alice);
 	/**
 	 * Derives a stream header key from the given master secret.
 	 * @param alice whether the key is for use by Alice or Bob.
 	 */
 	SecretKey deriveHeaderKey(SecretKey master, boolean alice);
 	/**
 	 * Derives a message authentication code key from the given master secret.
 	 * @param alice whether the key is for use by Alice or Bob.
 	 */
 	SecretKey deriveMacKey(SecretKey master, boolean alice);
 	/**
 	 * Derives a nonce from the given master secret for one of the parties to
 	 * sign.
 	 * @param alice whether the nonce is for use by Alice or Bob.
 	 */
 	byte[] deriveSignatureNonce(SecretKey master, boolean alice);
 	/**
 	 * Derives a commitment to the provided public key.
 	 * <p/>
 	 * Part of BQP.
 	 *
-	 * @param publicKey the public key
+	 * @param label a namespaced label indicating the purpose of the derived
-	 * @return the commitment to the provided public key.
+	 * key, to prevent it from being repurposed or colliding with a key derived
 	 * for another purpose
 	 */
-	byte[] deriveKeyCommitment(byte[] publicKey);
+	SecretKey deriveKey(String label, SecretKey k, byte[]... inputs);
 	/**
 	 * Derives a common shared secret from two public keys and one of the
 	 * corresponding private keys.
 	 * <p/>
 	 * Part of BQP.
 	 *
-	 * @param theirPublicKey the ephemeral public key of the remote party
+	 * @param label a namespaced label indicating the purpose of this shared
-	 * @param ourKeyPair our ephemeral keypair
+	 * secret, to prevent it from being repurposed or colliding with a shared
-	 * @param alice true if ourKeyPair belongs to Alice
+	 * secret derived for another purpose
 	 * @param theirPublicKey the public key of the remote party
 	 * @param ourKeyPair the key pair of the local party
 	 * @return the shared secret
 	 * @throws GeneralSecurityException
 	 */
-	SecretKey deriveSharedSecret(byte[] theirPublicKey, KeyPair ourKeyPair,
+	SecretKey deriveSharedSecret(String label, PublicKey theirPublicKey,
-			boolean alice) throws GeneralSecurityException;
+			KeyPair ourKeyPair, byte[]... inputs)
 			throws GeneralSecurityException;
 	/**
-	 * Derives the content of a confirmation record.
+	 * Signs the given byte[] with the given ECDSA private key.
 	 * <p/>
 	 * Part of BQP.
 	 *
-	 * @param sharedSecret the common shared secret
+	 * @param label a namespaced label indicating the purpose of this
-	 * @param theirPayload the commit payload from the remote party
+	 * signature, to prevent it from being repurposed or colliding with a
-	 * @param ourPayload the commit payload we sent
+	 * signature created for another purpose
 	 * @param theirPublicKey the ephemeral public key of the remote party
 	 * @param ourKeyPair our ephemeral keypair
 	 * @param alice true if ourKeyPair belongs to Alice
 	 * @param aliceRecord true if the confirmation record is for use by Alice
 	 * @return the confirmation record
 	 */
 	byte[] deriveConfirmationRecord(SecretKey sharedSecret,
 			byte[] theirPayload, byte[] ourPayload,
 			byte[] theirPublicKey, KeyPair ourKeyPair,
 			boolean alice, boolean aliceRecord);
 	/**
 	 * Derives a master secret from the given shared secret.
 	 * <p/>
 	 * Part of BQP.
 	 *
 	 * @param sharedSecret the common shared secret
 	 * @return the master secret
 	 */
 	SecretKey deriveMasterSecret(SecretKey sharedSecret);
 	/**
 	 * Derives a master secret from two public keys and one of the corresponding
 	 * private keys.
 	 * <p/>
 	 * This is a helper method that calls
 	 * deriveMasterSecret(deriveSharedSecret(theirPublicKey, ourKeyPair, alice))
 	 *
 	 * @param theirPublicKey the ephemeral public key of the remote party
 	 * @param ourKeyPair our ephemeral keypair
 	 * @param alice true if ourKeyPair belongs to Alice
 	 * @return the shared secret
 	 * @throws GeneralSecurityException
 	 */
 	SecretKey deriveMasterSecret(byte[] theirPublicKey, KeyPair ourKeyPair,
 			boolean alice) throws GeneralSecurityException;
 	/**
 	 * Derives initial transport keys for the given transport in the given
 	 * rotation period from the given master secret.
 	 * @param alice whether the keys are for use by Alice or Bob.
 	 */
 	TransportKeys deriveTransportKeys(TransportId t, SecretKey master,
 			long rotationPeriod, boolean alice);
 	/**
 	 * Rotates the given transport keys to the given rotation period. If the
 	 * keys are for a future rotation period they are not rotated.
 	 */
 	TransportKeys rotateTransportKeys(TransportKeys k, long rotationPeriod);
 	/** Encodes the pseudo-random tag that is used to recognise a stream. */
 	void encodeTag(byte[] tag, SecretKey tagKey, long streamNumber);
 	/**
 	 * Signs the given byte[] with the given PrivateKey.
 	 *
 	 * @param label A label specific to this signature
 	 *              to ensure that the signature cannot be repurposed
 	 */
 	byte[] sign(String label, byte[] toSign, byte[] privateKey)
 			throws GeneralSecurityException;
 	/**
-	 * Verifies that the given signature is valid for the signedData
+	 * Signs the given byte[] with the given Ed25519 private key.
 	 * and the given publicKey.
 	 *
-	 * @param label A label that was specific to this signature
+	 * @param label A label specific to this signature
 	 *              to ensure that the signature cannot be repurposed
 	 */
 	byte[] signEd(String label, byte[] toSign, byte[] privateKey)
 			throws GeneralSecurityException;
 	/**
 	 * Verifies that the given signature is valid for the signed data
 	 * and the given ECDSA public key.
 	 *
 	 * @param label a namespaced label indicating the purpose of this
 	 * signature, to prevent it from being repurposed or colliding with a
 	 * signature created for another purpose
 	 * @return true if the signature was valid, false otherwise.
 	 */
 	boolean verify(String label, byte[] signedData, byte[] publicKey,
 			byte[] signature) throws GeneralSecurityException;
 	/**
 	 * Verifies that the given signature is valid for the signed data
 	 * and the given Ed25519 public key.
 	 *
 	 * @param label A label that was specific to this signature
 	 *              to ensure that the signature cannot be repurposed
 	 * @return true if the signature was valid, false otherwise.
 	 */
 	boolean verifyEd(String label, byte[] signedData, byte[] publicKey,
 			byte[] signature) throws GeneralSecurityException;
 	/**
 	 * Returns the hash of the given inputs. The inputs are unambiguously
 	 * combined by prefixing each input with its length.
 	 *
-	 * @param label A label specific to this hash to ensure that hashes
+	 * @param label a namespaced label indicating the purpose of this hash, to
-	 *              calculated for distinct purposes don't collide.
+	 * prevent it from being repurposed or colliding with a hash created for
 	 * another purpose
 	 */
 	byte[] hash(String label, byte[]... inputs);
 	/**
 	 * Returns the length of hashes produced by
 	 * the {@link CryptoComponent#hash(String, byte[]...)} method.
 	 */
 	int getHashLength();
 	/**
 	 * Returns a message authentication code with the given key over the
 	 * given inputs. The inputs are unambiguously combined by prefixing each
 	 * input with its length.
 	 *
 	 * @param label a namespaced label indicating the purpose of this MAC, to
 	 * prevent it from being repurposed or colliding with a MAC created for
 	 * another purpose
 	 */
-	byte[] mac(SecretKey macKey, byte[]... inputs);
+	byte[] mac(String label, SecretKey macKey, byte[]... inputs);
 	/**
 	 * Encrypts and authenticates the given plaintext so it can be written to
@@ -0,0 +1,50 @@
 package org.briarproject.bramble.api.crypto;
 /**
 * Crypto operations for the key agreement protocol - see
 * https://code.briarproject.org/akwizgran/briar-spec/blob/master/protocols/BQP.md
 */
 public interface KeyAgreementCrypto {
 	/**
 	 * Hash label for public key commitment.
 	 */
 	String COMMIT_LABEL = "org.briarproject.bramble.keyagreement/COMMIT";
 	/**
 	 * Key derivation label for confirmation record.
 	 */
 	String CONFIRMATION_KEY_LABEL =
 			"org.briarproject.bramble.keyagreement/CONFIRMATION_KEY";
 	/**
 	 * MAC label for confirmation record.
 	 */
 	String CONFIRMATION_MAC_LABEL =
 			"org.briarproject.bramble.keyagreement/CONFIRMATION_MAC";
 	/**
 	 * Derives a commitment to the provided public key.
 	 *
 	 * @param publicKey the public key
 	 * @return the commitment to the provided public key.
 	 */
 	byte[] deriveKeyCommitment(PublicKey publicKey);
 	/**
 	 * Derives the content of a confirmation record.
 	 *
 	 * @param sharedSecret the common shared secret
 	 * @param theirPayload the key exchange payload of the remote party
 	 * @param ourPayload the key exchange payload of the local party
 	 * @param theirPublicKey the ephemeral public key of the remote party
 	 * @param ourKeyPair our ephemeral key pair of the local party
 	 * @param alice true if the local party is Alice
 	 * @param aliceRecord true if the confirmation record is for use by Alice
 	 * @return the confirmation record
 	 */
 	byte[] deriveConfirmationRecord(SecretKey sharedSecret,
 			byte[] theirPayload, byte[] ourPayload,
 			PublicKey theirPublicKey, KeyPair ourKeyPair,
 			boolean alice, boolean aliceRecord);
 }
@@ -6,9 +6,9 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 public interface PasswordStrengthEstimator {
 	float NONE = 0;
-	float WEAK = 0.4f;
+	float WEAK = 0.25f;
-	float QUITE_WEAK = 0.6f;
+	float QUITE_WEAK = 0.5f;
-	float QUITE_STRONG = 0.8f;
+	float QUITE_STRONG = 0.75f;
 	float STRONG = 1;
 	/**
@@ -1,12 +0,0 @@
 package org.briarproject.bramble.api.crypto;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 /**
 * A deterministic pseudo-random number generator.
 */
@NotNullByDefault
 public interface PseudoRandom {
 	byte[] nextBytes(int bytes);
 }
@@ -14,8 +14,9 @@ public interface StreamDecrypterFactory {
 	StreamDecrypter createStreamDecrypter(InputStream in, StreamContext ctx);
 	/**
-	 * Creates a {@link StreamDecrypter} for decrypting an invitation stream.
+	 * Creates a {@link StreamDecrypter} for decrypting a contact exchange
 	 * stream.
 	 */
-	StreamDecrypter createInvitationStreamDecrypter(InputStream in,
+	StreamDecrypter createContactExchangeStreamDecrypter(InputStream in,
 			SecretKey headerKey);
 }
@@ -14,8 +14,9 @@ public interface StreamEncrypterFactory {
 	StreamEncrypter createStreamEncrypter(OutputStream out, StreamContext ctx);
 	/**
-	 * Creates a {@link StreamEncrypter} for encrypting an invitation stream.
+	 * Creates a {@link StreamEncrypter} for encrypting a contact exchange
 	 * stream.
 	 */
-	StreamEncrypter createInvitationStreamEncrypter(OutputStream out,
+	StreamEncrypter createContactExchangeStreamDecrypter(OutputStream out,
 			SecretKey headerKey);
 }
@@ -0,0 +1,32 @@
 package org.briarproject.bramble.api.crypto;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.transport.TransportKeys;
 /**
 * Crypto operations for the transport security protocol - see
 * https://code.briarproject.org/akwizgran/briar-spec/blob/master/protocols/BTP.md
 */
 public interface TransportCrypto {
 	/**
 	 * Derives initial transport keys for the given transport in the given
 	 * rotation period from the given master secret.
 	 *
 	 * @param alice whether the keys are for use by Alice or Bob.
 	 */
 	TransportKeys deriveTransportKeys(TransportId t, SecretKey master,
 			long rotationPeriod, boolean alice);
 	/**
 	 * Rotates the given transport keys to the given rotation period. If the
 	 * keys are for the given period or any later period they are not rotated.
 	 */
 	TransportKeys rotateTransportKeys(TransportKeys k, long rotationPeriod);
 	/**
 	 * Encodes the pseudo-random tag that is used to recognise a stream.
 	 */
 	void encodeTag(byte[] tag, SecretKey tagKey, int protocolVersion,
 			long streamNumber);
 }
@@ -4,11 +4,14 @@ import org.briarproject.bramble.api.Bytes;
 import org.briarproject.bramble.api.FormatException;
 import java.util.Map;
-import java.util.concurrent.ConcurrentSkipListMap;
+import java.util.Map.Entry;
 import java.util.TreeMap;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.NotThreadSafe;
-public class BdfDictionary extends ConcurrentSkipListMap<String, Object> {
+@NotThreadSafe
 public class BdfDictionary extends TreeMap<String, Object> {
 	public static final Object NULL_VALUE = new Object();
@@ -3,15 +3,17 @@ package org.briarproject.bramble.api.data;
 import org.briarproject.bramble.api.Bytes;
 import org.briarproject.bramble.api.FormatException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Vector;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.NotThreadSafe;
 import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
-public class BdfList extends Vector<Object> {
+@NotThreadSafe
 public class BdfList extends ArrayList<Object> {
 	/**
 	 * Factory method for constructing lists inline.
@@ -122,8 +122,9 @@ public interface DatabaseComponent {
 			throws DbException;
 	/**
-	 * Deletes the message with the given ID. The message ID and any other
+	 * Deletes the message with the given ID. Unlike
-	 * associated data are not deleted.
+	 * {@link #removeMessage(Transaction, MessageId)}, the message ID and any
 	 * other associated data are not deleted.
 	 */
 	void deleteMessage(Transaction txn, MessageId m) throws DbException;
@@ -452,6 +453,11 @@ public interface DatabaseComponent {
 	 */
 	void removeLocalAuthor(Transaction txn, AuthorId a) throws DbException;
 	/**
 	 * Removes a message (and all associated state) from the database.
 	 */
 	void removeMessage(Transaction txn, MessageId m) throws DbException;
 	/**
 	 * Removes a transport (and all associated state) from the database.
 	 */
@@ -1,11 +1,11 @@
 package org.briarproject.bramble.api.db;
-import java.util.Hashtable;
+import java.util.TreeMap;
-import javax.annotation.concurrent.ThreadSafe;
+import javax.annotation.concurrent.NotThreadSafe;
-@ThreadSafe
+@NotThreadSafe
-public class Metadata extends Hashtable<String, byte[]> {
+public class Metadata extends TreeMap<String, byte[]> {
 	/**
 	 * Special value to indicate that a key is being removed.
@@ -45,7 +45,7 @@ public class Transaction {
 	 * committed.
 	 */
 	public void attach(Event e) {
-		if (events == null) events = new ArrayList<Event>();
+		if (events == null) events = new ArrayList<>();
 		events.add(e);
 	}
@@ -13,7 +13,9 @@ import javax.annotation.concurrent.Immutable;
@NotNullByDefault
 public class Author {
-	public enum Status {ANONYMOUS, UNKNOWN, UNVERIFIED, VERIFIED, OURSELVES}
+	public enum Status {
 		NONE, ANONYMOUS, UNKNOWN, UNVERIFIED, VERIFIED, OURSELVES
 	}
 	private final AuthorId id;
 	private final String name;
@@ -16,7 +16,7 @@ public class AuthorId extends UniqueId {
 	/**
 	 * Label for hashing authors to calculate their identities.
 	 */
-	public static final String LABEL = "org.briarproject.bramble.AUTHOR_ID";
+	public static final String LABEL = "org.briarproject.bramble/AUTHOR_ID";
 	public AuthorId(byte[] id) {
 		super(id);
@@ -1,20 +0,0 @@
 package org.briarproject.bramble.api.invitation;
 public interface InvitationConstants {
 	/**
 	 * The connection timeout in milliseconds.
 	 */
 	long CONNECTION_TIMEOUT = 60 * 1000;
 	/**
 	 * The confirmation timeout in milliseconds.
 	 */
 	long CONFIRMATION_TIMEOUT = 60 * 1000;
 	/**
 	 * The number of bits in an invitation or confirmation code. Codes must fit
 	 * into six decimal digits.
 	 */
 	int CODE_BITS = 19;
 }
@@ -1,47 +0,0 @@
 package org.briarproject.bramble.api.invitation;
 /**
 * An interface for receiving updates about the state of an
 * {@link InvitationTask}.
 */
 public interface InvitationListener {
 	/** Called if a connection to the remote peer is established. */
 	void connectionSucceeded();
 	/**
 	 * Called if a connection to the remote peer cannot be established. This
 	 * indicates that the protocol has ended unsuccessfully.
 	 */
 	void connectionFailed();
 	/** Called if key agreement with the remote peer succeeds. */
 	void keyAgreementSucceeded(int localCode, int remoteCode);
 	/**
 	 * Called if key agreement with the remote peer fails or the connection is
 	 * lost. This indicates that the protocol has ended unsuccessfully.
 	 */
 	void keyAgreementFailed();
 	/** Called if the remote peer's confirmation check succeeds. */
 	void remoteConfirmationSucceeded();
 	/**
 	 * Called if remote peer's confirmation check fails or the connection is
 	 * lost. This indicates that the protocol has ended unsuccessfully.
 	 */
 	void remoteConfirmationFailed();
 	/**
 	 * Called if the exchange of pseudonyms succeeds. This indicates that the
 	 * protocol has ended successfully.
 	 */
 	void pseudonymExchangeSucceeded(String remoteName);
 	/**
 	 * Called if the exchange of pseudonyms fails or the connection is lost.
 	 * This indicates that the protocol has ended unsuccessfully.
 	 */
 	void pseudonymExchangeFailed();
 }
@@ -1,85 +0,0 @@
 package org.briarproject.bramble.api.invitation;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 /**
 * A snapshot of the state of an {@link InvitationTask}.
 */
@Immutable
@NotNullByDefault
 public class InvitationState {
 	private final int localInvitationCode, remoteInvitationCode;
 	private final int localConfirmationCode, remoteConfirmationCode;
 	private final boolean connected, connectionFailed;
 	private final boolean localCompared, remoteCompared;
 	private final boolean localMatched, remoteMatched;
 	@Nullable
 	private final String contactName;
 	public InvitationState(int localInvitationCode, int remoteInvitationCode,
 			int localConfirmationCode, int remoteConfirmationCode,
 			boolean connected, boolean connectionFailed, boolean localCompared,
 			boolean remoteCompared, boolean localMatched,
 			boolean remoteMatched, @Nullable String contactName) {
 		this.localInvitationCode = localInvitationCode;
 		this.remoteInvitationCode = remoteInvitationCode;
 		this.localConfirmationCode = localConfirmationCode;
 		this.remoteConfirmationCode = remoteConfirmationCode;
 		this.connected = connected;
 		this.connectionFailed = connectionFailed;
 		this.localCompared = localCompared;
 		this.remoteCompared = remoteCompared;
 		this.localMatched = localMatched;
 		this.remoteMatched = remoteMatched;
 		this.contactName = contactName;
 	}
 	public int getLocalInvitationCode() {
 		return localInvitationCode;
 	}
 	public int getRemoteInvitationCode() {
 		return remoteInvitationCode;
 	}
 	public int getLocalConfirmationCode() {
 		return localConfirmationCode;
 	}
 	public int getRemoteConfirmationCode() {
 		return remoteConfirmationCode;
 	}
 	public boolean getConnected() {
 		return connected;
 	}
 	public boolean getConnectionFailed() {
 		return connectionFailed;
 	}
 	public boolean getLocalCompared() {
 		return localCompared;
 	}
 	public boolean getRemoteCompared() {
 		return remoteCompared;
 	}
 	public boolean getLocalMatched() {
 		return localMatched;
 	}
 	public boolean getRemoteMatched() {
 		return remoteMatched;
 	}
 	@Nullable
 	public String getContactName() {
 		return contactName;
 	}
 }
@@ -1,38 +0,0 @@
 package org.briarproject.bramble.api.invitation;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 /**
 * A task for exchanging invitations with a remote peer.
 */
@NotNullByDefault
 public interface InvitationTask {
 	/**
 	 * Adds a listener to be informed of state changes and returns the
 	 * task's current state.
 	 */
 	InvitationState addListener(InvitationListener l);
 	/**
 	 * Removes the given listener.
 	 */
 	void removeListener(InvitationListener l);
 	/**
 	 * Asynchronously starts the connection process.
 	 */
 	void connect();
 	/**
 	 * Asynchronously informs the remote peer that the local peer's
 	 * confirmation codes matched.
 	 */
 	void localConfirmationSucceeded();
 	/**
 	 * Asynchronously informs the remote peer that the local peer's
 	 * confirmation codes did not match.
 	 */
 	void localConfirmationFailed();
 }
@@ -1,15 +0,0 @@
 package org.briarproject.bramble.api.invitation;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 /**
 * Creates tasks for exchanging invitations with remote peers.
 */
@NotNullByDefault
 public interface InvitationTaskFactory {
 	/**
 	 * Creates a task using the given local and remote invitation codes.
 	 */
 	InvitationTask createTask(int localCode, int remoteCode);
 }
@@ -5,7 +5,7 @@ public interface KeyAgreementConstants {
 	/**
 	 * The current version of the BQP protocol.
 	 */
-	byte PROTOCOL_VERSION = 2;
+	byte PROTOCOL_VERSION = 3;
 	/**
 	 * The length of the record header in bytes.
@@ -22,7 +22,10 @@ public interface KeyAgreementConstants {
 	 */
 	int COMMIT_LENGTH = 16;
-	long CONNECTION_TIMEOUT = 20 * 1000; // Milliseconds
+	/**
 	 * The connection timeout in milliseconds.
 	 */
 	long CONNECTION_TIMEOUT = 20 * 1000;
 	/**
 	 * The transport identifier for Bluetooth.
@@ -33,4 +36,16 @@ public interface KeyAgreementConstants {
 	 * The transport identifier for LAN.
 	 */
 	int TRANSPORT_ID_LAN = 1;
 	/**
 	 * Label for deriving the shared secret.
 	 */
 	String SHARED_SECRET_LABEL =
 			"org.briarproject.bramble.keyagreement/SHARED_SECRET";
 	/**
 	 * Label for deriving the master secret.
 	 */
 	String MASTER_SECRET_LABEL =
 			"org.briarproject.bramble.keyagreement/MASTER_SECRET";
 }
@@ -1,15 +0,0 @@
 package org.briarproject.bramble.api.keyagreement;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 /**
 * Manages tasks for conducting key agreements with remote peers.
 */
@NotNullByDefault
 public interface KeyAgreementTaskFactory {
 	/**
 	 * Gets the current key agreement task.
 	 */
 	KeyAgreementTask createTask();
 }
@@ -9,4 +9,5 @@ public interface BluetoothConstants {
 	String PROP_ADDRESS = "address";
 	String PROP_UUID = "uuid";
 	String PREF_BT_ENABLE = "enable";
 }
@@ -4,4 +4,10 @@ public interface LanTcpConstants {
 	TransportId ID = new TransportId("org.briarproject.bramble.lan");
 	// a transport property (shared with contacts)
 	String PROP_IP_PORTS = "ipPorts";
 	// a local setting
 	String PREF_LAN_IP_PORTS = "ipPorts";
 }
@@ -3,7 +3,6 @@ package org.briarproject.bramble.api.plugin;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.IOException;
 import java.util.Collection;
@NotNullByDefault
@@ -25,14 +24,14 @@ public interface Plugin {
 	int getMaxIdleTime();
 	/**
-	 * Starts the plugin and returns true if it started successfully.
+	 * Starts the plugin.
 	 */
-	boolean start() throws IOException;
+	void start() throws PluginException;
 	/**
 	 * Stops the plugin.
 	 */
-	void stop() throws IOException;
+	void stop() throws PluginException;
 	/**
 	 * Returns true if the plugin is running.
@@ -29,6 +29,11 @@ public interface PluginCallback {
 	 */
 	Map<ContactId, TransportProperties> getRemoteProperties();
 	/**
 	 * Returns the plugin's remote transport properties for the given contact.
 	 */
 	TransportProperties getRemoteProperties(ContactId c);
 	/**
 	 * Merges the given settings with the namespaced settings
 	 */
@@ -0,0 +1,15 @@
 package org.briarproject.bramble.api.plugin;
 /**
 * An exception that indicates an error starting or stopping a {@link Plugin}.
 */
 public class PluginException extends Exception {
 	public PluginException() {
 		super();
 	}
 	public PluginException(Throwable cause) {
 		super(cause);
 	}
 }
@@ -32,11 +32,6 @@ public interface PluginManager {
 	 */
 	Collection<DuplexPlugin> getDuplexPlugins();
 	/**
 	 * Returns any duplex plugins that support invitations.
 	 */
 	Collection<DuplexPlugin> getInvitationPlugins();
 	/**
 	 * Returns any duplex plugins that support key agreement.
 	 */
@@ -4,8 +4,19 @@ public interface TorConstants {
 	TransportId ID = new TransportId("org.briarproject.bramble.tor");
 	String PROP_ONION = "onion";
 	int SOCKS_PORT = 59050;
 	int CONTROL_PORT = 59051;
 	int CONNECT_TO_PROXY_TIMEOUT = 5000; // Milliseconds
 	int EXTRA_SOCKET_TIMEOUT = 30000; // Milliseconds
 	String PREF_TOR_NETWORK = "network";
 	String PREF_TOR_PORT = "port";
 	int PREF_TOR_NETWORK_NEVER = 0;
 	int PREF_TOR_NETWORK_WIFI = 1;
 	int PREF_TOR_NETWORK_ALWAYS = 2;
 }
@@ -1,7 +1,6 @@
 package org.briarproject.bramble.api.plugin.duplex;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.crypto.PseudoRandom;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
@@ -23,20 +22,6 @@ public interface DuplexPlugin extends Plugin {
 	@Nullable
 	DuplexTransportConnection createConnection(ContactId c);
 	/**
 	 * Returns true if the plugin supports exchanging invitations.
 	 */
 	boolean supportsInvitations();
 	/**
 	 * Attempts to create and return an invitation connection to the remote
 	 * peer. Returns null if no connection can be established within the given
 	 * time.
 	 */
 	@Nullable
 	DuplexTransportConnection createInvitationConnection(PseudoRandom r,
 			long timeout, boolean alice);
 	/**
 	 * Returns true if the plugin supports short-range key agreement.
 	 */
@@ -0,0 +1,15 @@
 package org.briarproject.bramble.api.plugin.event;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import javax.annotation.concurrent.Immutable;
 /**
 * An event that asks the Bluetooth plugin to disable the Bluetooth adapter if
 * we previously enabled it.
 */
@Immutable
@NotNullByDefault
 public class DisableBluetoothEvent extends Event {
 }
@@ -0,0 +1,14 @@
 package org.briarproject.bramble.api.plugin.event;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import javax.annotation.concurrent.Immutable;
 /**
 * An event asks the Bluetooth plugin to enable the Bluetooth adapter.
 */
@Immutable
@NotNullByDefault
 public class EnableBluetoothEvent extends Event {
 }
@@ -17,6 +17,11 @@ public interface TransportPropertyManager {
 	 */
 	ClientId CLIENT_ID = new ClientId("org.briarproject.briar.properties");
 	/**
 	 * The current version of the transport property client.
 	 */
 	int CLIENT_VERSION = 0;
 	/**
 	 * Stores the given properties received while adding a contact - they will
 	 * be superseded by any properties synced from the contact.
@@ -33,7 +38,7 @@ public interface TransportPropertyManager {
 	/**
 	 * Returns the local transport properties for all transports.
 	 * <br/>
-	 * Read-Only
+	 * TODO: Transaction can be read-only when code is simplified
 	 */
 	Map<TransportId, TransportProperties> getLocalProperties(Transaction txn)
 			throws DbException;
@@ -49,6 +54,13 @@ public interface TransportPropertyManager {
 	Map<ContactId, TransportProperties> getRemoteProperties(TransportId t)
 			throws DbException;
 	/**
 	 * Returns the remote transport properties for the given contact and
 	 * transport.
 	 */
 	TransportProperties getRemoteProperties(ContactId c, TransportId t)
 			throws DbException;
 	/**
 	 * Merges the given properties with the existing local properties for the
 	 * given transport.
@@ -3,7 +3,7 @@ package org.briarproject.bramble.api.sync;
 import java.util.Collection;
 /**
- * A packet acknowledging receipt of one or more {@link Message Messages}.
+ * A record acknowledging receipt of one or more {@link Message Messages}.
 */
 public class Ack {
@@ -36,4 +36,8 @@ public class ClientId implements Comparable<ClientId> {
 		return id.hashCode();
 	}
 	@Override
 	public String toString() {
 		return id;
 	}
 }
@@ -1,5 +1,7 @@
 package org.briarproject.bramble.api.sync;
 import static org.briarproject.bramble.api.sync.SyncConstants.MAX_GROUP_DESCRIPTOR_LENGTH;
 public class Group {
 	public enum Visibility {
@@ -13,6 +15,8 @@ public class Group {
 	private final byte[] descriptor;
 	public Group(GroupId id, ClientId clientId, byte[] descriptor) {
 		if (descriptor.length > MAX_GROUP_DESCRIPTOR_LENGTH)
 			throw new IllegalArgumentException();
 		this.id = id;
 		this.clientId = clientId;
 		this.descriptor = descriptor;
@@ -6,7 +6,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 public interface GroupFactory {
 	/**
-	 * Creates a group with the given client ID and descriptor.
+	 * Creates a group with the given client ID, client version and descriptor.
 	 */
-	Group createGroup(ClientId c, byte[] descriptor);
+	Group createGroup(ClientId c, int clientVersion, byte[] descriptor);
 }
@@ -15,7 +15,7 @@ public class GroupId extends UniqueId {
 	/**
 	 * Label for hashing groups to calculate their identifiers.
 	 */
-	public static final String LABEL = "org.briarproject.bramble.GROUP_ID";
+	public static final String LABEL = "org.briarproject.bramble/GROUP_ID";
 	public GroupId(byte[] id) {
 		super(id);
@@ -22,7 +22,7 @@ public class MessageContext {
 	}
 	public MessageContext(Metadata metadata) {
-		this(metadata, Collections.<MessageId>emptyList());
+		this(metadata, Collections.emptyList());
 	}
 	public Metadata getMetadata() {
@@ -16,7 +16,7 @@ public class MessageId extends UniqueId {
 	/**
 	 * Label for hashing messages to calculate their identifiers.
 	 */
-	public static final String LABEL = "org.briarproject.bramble.MESSAGE_ID";
+	public static final String LABEL = "org.briarproject.bramble/MESSAGE_ID";
 	public MessageId(byte[] id) {
 		super(id);
@@ -3,7 +3,7 @@ package org.briarproject.bramble.api.sync;
 import java.util.Collection;
 /**
- * A packet offering the recipient one or more {@link Message Messages}.
+ * A record offering the recipient one or more {@link Message Messages}.
 */
 public class Offer {
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.IOException;
@NotNullByDefault
-public interface PacketReader {
+public interface RecordReader {
 	boolean eof() throws IOException;
@@ -24,4 +24,5 @@ public interface PacketReader {
 	boolean hasRequest() throws IOException;
 	Request readRequest() throws IOException;
 }
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.InputStream;
@NotNullByDefault
-public interface PacketReaderFactory {
+public interface RecordReaderFactory {
-	PacketReader createPacketReader(InputStream in);
+	RecordReader createRecordReader(InputStream in);
 }
@@ -1,12 +1,13 @@
 package org.briarproject.bramble.api.sync;
 /**
- * Packet types for the sync protocol.
+ * Record types for the sync protocol.
 */
-public interface PacketTypes {
+public interface RecordTypes {
 	byte ACK = 0;
 	byte MESSAGE = 1;
 	byte OFFER = 2;
 	byte REQUEST = 3;
 }
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.IOException;
@NotNullByDefault
-public interface PacketWriter {
+public interface RecordWriter {
 	void writeAck(Ack a) throws IOException;
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.OutputStream;
@NotNullByDefault
-public interface PacketWriterFactory {
+public interface RecordWriterFactory {
-	PacketWriter createPacketWriter(OutputStream out);
+	RecordWriter createRecordWriter(OutputStream out);
 }
@@ -3,7 +3,7 @@ package org.briarproject.bramble.api.sync;
 import java.util.Collection;
 /**
- * A packet requesting one or more {@link Message Messages} from the recipient.
+ * A record requesting one or more {@link Message Messages} from the recipient.
 */
 public class Request {
@@ -10,19 +10,17 @@ public interface SyncConstants {
 	byte PROTOCOL_VERSION = 0;
 	/**
-	 * The length of the packet header in bytes.
+	 * The length of the record header in bytes.
 	 */
-	int PACKET_HEADER_LENGTH = 4;
+	int RECORD_HEADER_LENGTH = 4;
 	/**
-	 * The maximum length of the packet payload in bytes.
+	 * The maximum length of the record payload in bytes.
 	 */
-	int MAX_PACKET_PAYLOAD_LENGTH = 32 * 1024; // 32 KiB
+	int MAX_RECORD_PAYLOAD_LENGTH = 48 * 1024; // 48 KiB
-	/**
+	/** The maximum length of a group descriptor in bytes. */
-	 * The maximum length of a message in bytes.
+	int MAX_GROUP_DESCRIPTOR_LENGTH = 16 * 1024; // 16 KiB
 	 */
 	int MAX_MESSAGE_LENGTH = MAX_PACKET_PAYLOAD_LENGTH - PACKET_HEADER_LENGTH;
 	/**
 	 * The length of the message header in bytes.
@@ -32,10 +30,15 @@ public interface SyncConstants {
 	/**
 	 * The maximum length of a message body in bytes.
 	 */
-	int MAX_MESSAGE_BODY_LENGTH = MAX_MESSAGE_LENGTH - MESSAGE_HEADER_LENGTH;
+	int MAX_MESSAGE_BODY_LENGTH = 32 * 1024; // 32 KiB
 	/**
-	 * The maximum number of message IDs in an ack, offer or request packet.
+	 * The maximum length of a message in bytes.
 	 */
-	int MAX_MESSAGE_IDS = MAX_PACKET_PAYLOAD_LENGTH / UniqueId.LENGTH;
+	int MAX_MESSAGE_LENGTH = MESSAGE_HEADER_LENGTH + MAX_MESSAGE_BODY_LENGTH;
 	/**
 	 * The maximum number of message IDs in an ack, offer or request record.
 	 */
 	int MAX_MESSAGE_IDS = MAX_RECORD_PAYLOAD_LENGTH / UniqueId.LENGTH;
 }
@@ -5,7 +5,7 @@ import java.io.IOException;
 public interface SyncSession {
 	/**
-	 * Runs the session. This method returns when there are no more packets to
+	 * Runs the session. This method returns when there are no more records to
 	 * send or receive, or when the {@link #interrupt()} method has been called.
 	 */
 	void run() throws IOException;
@@ -0,0 +1,23 @@
 package org.briarproject.bramble.api.system;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.security.Provider;
 import java.security.SecureRandom;
 import javax.annotation.Nullable;
 /**
 * Wrapper for a platform-specific secure random number generator.
 */
@NotNullByDefault
 public interface SecureRandomProvider {
 	/**
 	 * Returns a {@link Provider} that provides a strong {@link SecureRandom}
 	 * implementation, or null if the platform's default implementation should
 	 * be used.
 	 */
 	@Nullable
 	Provider getProvider();
 }
@@ -1,18 +0,0 @@
 package org.briarproject.bramble.api.system;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 /**
 * Uses a platform-specific source to provide a seed for a pseudo-random
 * number generator.
 */
@NotNullByDefault
 public interface SeedProvider {
 	/**
 	 * The length of the seed in bytes.
 	 */
 	int SEED_BYTES = 32;
 	byte[] getSeed();
 }
@@ -15,9 +15,9 @@ public interface StreamReaderFactory {
 	InputStream createStreamReader(InputStream in, StreamContext ctx);
 	/**
-	 * Creates an {@link InputStream InputStream} for reading from an
+	 * Creates an {@link InputStream InputStream} for reading from a contact
-	 * invitation stream.
+	 * exchangestream.
 	 */
-	InputStream createInvitationStreamReader(InputStream in,
+	InputStream createContactExchangeStreamReader(InputStream in,
 			SecretKey headerKey);
 }
@@ -15,9 +15,9 @@ public interface StreamWriterFactory {
 	OutputStream createStreamWriter(OutputStream out, StreamContext ctx);
 	/**
-	 * Creates an {@link OutputStream OutputStream} for writing to an
+	 * Creates an {@link OutputStream OutputStream} for writing to a contact
-	 * invitation stream.
+	 * exchange stream.
 	 */
-	OutputStream createInvitationStreamWriter(OutputStream out,
+	OutputStream createContactExchangeStreamWriter(OutputStream out,
 			SecretKey headerKey);
 }
@@ -4,6 +4,11 @@ import org.briarproject.bramble.api.crypto.SecretKey;
 public interface TransportConstants {
 	/**
 	 * The current version of the transport protocol.
 	 */
 	int PROTOCOL_VERSION = 4;
 	/**
 	 * The length of the pseudo-random tag in bytes.
 	 */
@@ -14,21 +19,22 @@ public interface TransportConstants {
 	 */
 	int STREAM_HEADER_NONCE_LENGTH = 24;
 	/**
 	 * The length of the stream header initialisation vector (IV) in bytes.
 	 */
 	int STREAM_HEADER_IV_LENGTH = STREAM_HEADER_NONCE_LENGTH - 8;
 	/**
 	 * The length of the message authentication code (MAC) in bytes.
 	 */
 	int MAC_LENGTH = 16;
 	/**
 	 * The length of the stream header plaintext in bytes. The stream header
 	 * contains the protocol version, stream number and frame key.
 	 */
 	int STREAM_HEADER_PLAINTEXT_LENGTH = 2 + 8 + SecretKey.LENGTH;
 	/**
 	 * The length of the stream header in bytes.
 	 */
-	int STREAM_HEADER_LENGTH = STREAM_HEADER_IV_LENGTH + SecretKey.LENGTH
+	int STREAM_HEADER_LENGTH = STREAM_HEADER_NONCE_LENGTH
-			+ MAC_LENGTH;
+			+ STREAM_HEADER_PLAINTEXT_LENGTH + MAC_LENGTH;
 	/**
 	 * The length of the frame nonce in bytes.
@@ -74,4 +80,32 @@ public interface TransportConstants {
 	 * The size of the reordering window.
 	 */
 	int REORDERING_WINDOW_SIZE = 32;
 	/**
 	 * Label for deriving Alice's initial tag key from the master secret.
 	 */
 	String ALICE_TAG_LABEL = "org.briarproject.bramble.transport/ALICE_TAG_KEY";
 	/**
 	 * Label for deriving Bob's initial tag key from the master secret.
 	 */
 	String BOB_TAG_LABEL = "org.briarproject.bramble.transport/BOB_TAG_KEY";
 	/**
 	 * Label for deriving Alice's initial header key from the master secret.
 	 */
 	String ALICE_HEADER_LABEL =
 			"org.briarproject.bramble.transport/ALICE_HEADER_KEY";
 	/**
 	 * Label for deriving Bob's initial header key from the master secret.
 	 */
 	String BOB_HEADER_LABEL =
 			"org.briarproject.bramble.transport/BOB_HEADER_KEY";
 	/**
 	 * Label for deriving the next period's key in key rotation.
 	 */
 	String ROTATE_LABEL = "org.briarproject.bramble.transport/ROTATE";
 }
@@ -8,6 +8,7 @@ import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.net.Socket;
 import javax.annotation.Nullable;
@@ -59,4 +60,24 @@ public class IoUtils {
 			offset += read;
 		}
 	}
 	// Workaround for a bug in Android 7, see
 	// https://android-review.googlesource.com/#/c/271775/
 	public static InputStream getInputStream(Socket s) throws IOException {
 		try {
 			return s.getInputStream();
 		} catch (NullPointerException e) {
 			throw new IOException(e);
 		}
 	}
 	// Workaround for a bug in Android 7, see
 	// https://android-review.googlesource.com/#/c/271775/
 	public static OutputStream getOutputStream(Socket s) throws IOException {
 		try {
 			return s.getOutputStream();
 		} catch (NullPointerException e) {
 			throw new IOException(e);
 		}
 	}
 }
@@ -19,7 +19,7 @@ public class PrivacyUtils {
 	@Nullable
 	public static String scrubMacAddress(@Nullable String address) {
-		if (address == null) return null;
+		if (address == null || address.length() == 0) return null;
 		// this is a fake address we need to know about
 		if (address.equals("02:00:00:00:00:00")) return address;
 		// keep first and last octet of MAC address
@@ -8,6 +8,7 @@ import java.nio.charset.CharacterCodingException;
 import java.nio.charset.Charset;
 import java.nio.charset.CharsetDecoder;
 import java.util.Collection;
 import java.util.Random;
 import java.util.regex.Pattern;
 import javax.annotation.Nullable;
@@ -27,6 +28,7 @@ public class StringUtils {
 			'0', '1', '2', '3', '4', '5', '6', '7',
 			'8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 	};
 	private static final Random random = new Random();
 	public static boolean isNullOrEmpty(@Nullable String s) {
 		return s == null || s.length() == 0;
@@ -139,4 +141,12 @@ public class StringUtils {
 		}
 		return s.toString();
 	}
 	public static String getRandomString(int length) {
 		char[] c = new char[length];
 		for (int i = 0; i < length; i++)
 			c[i] = (char) ('a' + random.nextInt(26));
 		return new String(c);
 	}
 }
@@ -1,9 +1,7 @@
-package org.briarproject.bramble.data;
+package org.briarproject.bramble.api.data;
 import org.briarproject.BriarTestCase;
 import org.briarproject.bramble.api.Bytes;
-import org.briarproject.bramble.api.data.BdfDictionary;
+import org.briarproject.bramble.test.BrambleTestCase;
 import org.briarproject.bramble.api.data.BdfEntry;
 import org.junit.Test;
 import java.util.Collections;
@@ -15,7 +13,7 @@ import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
-public class BdfDictionaryTest extends BriarTestCase {
+public class BdfDictionaryTest extends BrambleTestCase {
 	@Test
 	public void testConstructors() {
@@ -1,11 +1,8 @@
-package org.briarproject.bramble.data;
+package org.briarproject.bramble.api.data;
 import org.briarproject.BriarTestCase;
 import org.briarproject.bramble.api.Bytes;
 import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.data.BdfDictionary;
+import org.briarproject.bramble.test.BrambleTestCase;
 import org.briarproject.bramble.api.data.BdfEntry;
 import org.briarproject.bramble.api.data.BdfList;
 import org.junit.Test;
 import java.util.Arrays;
@@ -15,7 +12,7 @@ import static org.briarproject.bramble.api.data.BdfDictionary.NULL_VALUE;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
-public class BdfListTest extends BriarTestCase {
+public class BdfListTest extends BrambleTestCase {
 	@Test
 	public void testConstructors() {
@@ -1,9 +1,9 @@
-package org.briarproject;
+package org.briarproject.bramble.test;
 import org.jmock.Mockery;
 import org.junit.After;
-public abstract class BriarMockTestCase extends BriarTestCase {
+public abstract class BrambleMockTestCase extends BrambleTestCase {
 	protected final Mockery context = new Mockery();
@@ -0,0 +1,17 @@
 package org.briarproject.bramble.test;
 import java.lang.Thread.UncaughtExceptionHandler;
 import static org.junit.Assert.fail;
 public abstract class BrambleTestCase {
 	public BrambleTestCase() {
 		// Ensure exceptions thrown on worker threads cause tests to fail
 		UncaughtExceptionHandler fail = (thread, throwable) -> {
 			throwable.printStackTrace();
 			fail();
 		};
 		Thread.setDefaultUncaughtExceptionHandler(fail);
 	}
 }
@@ -0,0 +1,41 @@
 package org.briarproject.bramble.test;
 import org.briarproject.bramble.api.UniqueId;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.util.IoUtils;
 import java.io.File;
 import java.util.Random;
 import java.util.concurrent.atomic.AtomicInteger;
 public class TestUtils {
 	private static final AtomicInteger nextTestDir =
 			new AtomicInteger((int) (Math.random() * 1000 * 1000));
 	private static final Random random = new Random();
 	public static File getTestDirectory() {
 		int name = nextTestDir.getAndIncrement();
 		return new File("test.tmp/" + name);
 	}
 	public static void deleteTestDirectory(File testDir) {
 		IoUtils.deleteFileOrDir(testDir);
 		testDir.getParentFile().delete(); // Delete if empty
 	}
 	public static byte[] getRandomBytes(int length) {
 		byte[] b = new byte[length];
 		random.nextBytes(b);
 		return b;
 	}
 	public static byte[] getRandomId() {
 		return getRandomBytes(UniqueId.LENGTH);
 	}
 	public static SecretKey getSecretKey() {
 		return new SecretKey(getRandomBytes(SecretKey.LENGTH));
 	}
 }
@@ -1,3 +1,4 @@
 bin
 build
 test.tmp
 .settings
@@ -1,19 +1,76 @@
-apply plugin: 'java'
+apply plugin: 'java-library'
-sourceCompatibility = 1.6
+sourceCompatibility = 1.8
-targetCompatibility = 1.6
+targetCompatibility = 1.8
 apply plugin: 'net.ltgt.apt'
 apply plugin: 'idea'
 apply plugin: 'witness'
 dependencies {
-	compile project(':bramble-api')
+	implementation project(path: ':bramble-api', configuration: 'default')
-	compile fileTree(dir: 'libs', include: '*.jar')
+	implementation 'com.madgag.spongycastle:core:1.58.0.0'
-	compile 'com.madgag.spongycastle:core:1.54.0.0'
+	implementation 'com.h2database:h2:1.4.192' // The last version that supports Java 1.6
-	compile 'com.h2database:h2:1.4.190'
+	implementation 'org.bitlet:weupnp:0.1.4'
 	implementation 'net.i2p.crypto:eddsa:0.2.0'
 	apt 'com.google.dagger:dagger-compiler:2.0.2'
 	testImplementation project(path: ':bramble-api', configuration: 'testOutput')
 	testImplementation 'org.hsqldb:hsqldb:2.3.5' // The last version that supports Java 1.6
 	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"
 	testImplementation "org.whispersystems:curve25519-java:0.4.1"
 	testApt 'com.google.dagger:dagger-compiler:2.0.2'
 }
 dependencyVerification {
 	verify = [
-			'com.madgag.spongycastle:core:1e7fa4b19ccccd1011364ab838d0b4702470c178bbbdd94c5c90b2d4d749ea1e',
+			'cglib:cglib:3.2.0:cglib-3.2.0.jar:adb13bab79712ad6bdf1bd59f2a3918018a8016e722e8a357065afb9e6690861',
-			'com.h2database:h2:23ba495a07bbbb3bd6c3084d10a96dad7a23741b8b6d64b213459a784195a98c'
+			'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
 			'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.guava:guava:18.0:guava-18.0.jar:d664fbfc03d2e5ce9cab2a44fb01f1d0bf9dfebeccc1a473b1f9ea31f79f6f99',
 			'com.h2database:h2:1.4.192:h2-1.4.192.jar:225b22e9857235c46c93861410b60b8c81c10dc8985f4faf188985ba5445126c',
 			'com.madgag.spongycastle:core:1.58.0.0:core-1.58.0.0.jar:199617dd5698c5a9312b898c0a4cec7ce9dd8649d07f65d91629f58229d72728',
 			'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
 			'junit:junit:4.12:junit-4.12.jar:59721f0805e223d84b90677887d9ff567dc534d7c502ca903c0c2b17f05c116a',
 			'net.i2p.crypto:eddsa:0.2.0:eddsa-0.2.0.jar:a7cb1b85c16e2f0730b9204106929a1d9aaae1df728adc7041a8b8b605692140',
 			'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.beanshell:bsh:1.3.0:bsh-1.3.0.jar:9b04edc75d19db54f1b4e8b5355e9364384c6cf71eb0a1b9724c159d779879f8',
 			'org.bitlet:weupnp:0.1.4:weupnp-0.1.4.jar:88df7e6504929d00bdb832863761385c68ab92af945b04f0770b126270a444fb',
 			'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.hsqldb:hsqldb:2.3.5:hsqldb-2.3.5.jar:6676a6977ac98997a80f827ddbd3fe8ca1e0853dad1492512135fd1a222ccfad',
 			'org.jmock:jmock-junit4:2.8.2:jmock-junit4-2.8.2.jar:f7ee4df4f7bd7b7f1cafad3b99eb74d579f109d5992ff625347352edb55e674c',
 			'org.jmock:jmock-legacy:2.8.2:jmock-legacy-2.8.2.jar:f2b985a5c08a9edb7f37612330c058809da3f6a6d63ce792426ebf8ff0d6d31b',
 			'org.jmock:jmock-testjar:2.8.2:jmock-testjar-2.8.2.jar:8900860f72c474e027cf97fe78dcbf154a1aa7fc62b6845c5fb4e4f3c7bc8760',
 			'org.jmock:jmock:2.8.2:jmock-2.8.2.jar:6c73cb4a2e6dbfb61fd99c9a768539c170ab6568e57846bd60dbf19596b65b16',
 			'org.objenesis:objenesis:2.1:objenesis-2.1.jar:c74330cc6b806c804fd37e74487b4fe5d7c2750c5e15fbc6efa13bdee1bdef80',
 			'org.ow2.asm:asm:5.0.4:asm-5.0.4.jar:896618ed8ae62702521a78bc7be42b7c491a08e6920a15f89a3ecdec31e9a220',
 			'org.whispersystems:curve25519-java:0.4.1:curve25519-java-0.4.1.jar:7dd659d8822c06c3aea1a47f18fac9e5761e29cab8100030b877db445005f03e',
 	]
 }
 // needed to make test output available to bramble-j2se
 configurations {
 	testOutput.extendsFrom(testCompile)
 }
 task jarTest(type: Jar, dependsOn: testClasses) {
 	from sourceSets.test.output
 	classifier = 'test'
 }
 artifacts {
 	testOutput jarTest
 }
 // If a Java 6 JRE is available, check we're not using any Java 7 or 8 APIs
 tasks.withType(JavaCompile) {
 	useJava6StandardLibrary(it)
 }
@@ -8,7 +8,6 @@ import org.briarproject.bramble.db.DatabaseExecutorModule;
 import org.briarproject.bramble.db.DatabaseModule;
 import org.briarproject.bramble.event.EventModule;
 import org.briarproject.bramble.identity.IdentityModule;
 import org.briarproject.bramble.invitation.InvitationModule;
 import org.briarproject.bramble.keyagreement.KeyAgreementModule;
 import org.briarproject.bramble.lifecycle.LifecycleModule;
 import org.briarproject.bramble.plugin.PluginModule;
@@ -32,7 +31,6 @@ import dagger.Module;
 		DatabaseExecutorModule.class,
 		EventModule.class,
 		IdentityModule.class,
 		InvitationModule.class,
 		KeyAgreementModule.class,
 		LifecycleModule.class,
 		PluginModule.class,
@@ -54,6 +52,7 @@ public class BrambleCoreModule {
 		c.inject(new IdentityModule.EagerSingletons());
 		c.inject(new LifecycleModule.EagerSingletons());
 		c.inject(new PluginModule.EagerSingletons());
 		c.inject(new PropertiesModule.EagerSingletons());
 		c.inject(new SyncModule.EagerSingletons());
 		c.inject(new SystemModule.EagerSingletons());
 		c.inject(new TransportModule.EagerSingletons());
@@ -0,0 +1,81 @@
 package org.briarproject.bramble;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.util.LinkedList;
 import java.util.Queue;
 import java.util.concurrent.Executor;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.concurrent.GuardedBy;
 import static java.util.logging.Level.FINE;
 /**
 * An {@link Executor} that delegates its tasks to another {@link Executor}
 * while limiting the number of tasks that are delegated concurrently. Tasks
 * are delegated in the order they are submitted to this executor.
 */
@NotNullByDefault
 public class PoliteExecutor implements Executor {
 	private static final Level LOG_LEVEL = FINE;
 	private final Object lock = new Object();
 	@GuardedBy("lock")
 	private final Queue<Runnable> queue = new LinkedList<>();
 	private final Executor delegate;
 	private final int maxConcurrentTasks;
 	private final Logger log;
 	@GuardedBy("lock")
 	private int concurrentTasks = 0;
 	/**
 	 * @param tag the tag to be used for logging
 	 * @param delegate the executor to which tasks will be delegated
 	 * @param maxConcurrentTasks the maximum number of tasks that will be
 	 * delegated concurrently. If this is set to 1, tasks submitted to this
 	 * executor will run in the order they are submitted and will not run
 	 * concurrently
 	 */
 	public PoliteExecutor(String tag, Executor delegate,
 			int maxConcurrentTasks) {
 		this.delegate = delegate;
 		this.maxConcurrentTasks = maxConcurrentTasks;
 		log = Logger.getLogger(tag);
 	}
 	@Override
 	public void execute(Runnable r) {
 		long submitted = System.currentTimeMillis();
 		Runnable wrapped = () -> {
 			if (log.isLoggable(LOG_LEVEL)) {
 				long queued = System.currentTimeMillis() - submitted;
 				log.log(LOG_LEVEL, "Queue time " + queued + " ms");
 			}
 			try {
 				r.run();
 			} finally {
 				scheduleNext();
 			}
 		};
 		synchronized (lock) {
 			if (concurrentTasks < maxConcurrentTasks) {
 				concurrentTasks++;
 				delegate.execute(wrapped);
 			} else {
 				queue.add(wrapped);
 			}
 		}
 	}
 	private void scheduleNext() {
 		synchronized (lock) {
 			Runnable next = queue.poll();
 			if (next == null) concurrentTasks--;
 			else delegate.execute(next);
 		}
 	}
 }
@@ -0,0 +1,46 @@
 package org.briarproject.bramble;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import static java.util.logging.Level.FINE;
@NotNullByDefault
 public class TimeLoggingExecutor extends ThreadPoolExecutor {
 	private static final Level LOG_LEVEL = FINE;
 	private final Logger log;
 	public TimeLoggingExecutor(String tag, int corePoolSize, int maxPoolSize,
 			long keepAliveTime, TimeUnit unit,
 			BlockingQueue<Runnable> workQueue,
 			RejectedExecutionHandler handler) {
 		super(corePoolSize, maxPoolSize, keepAliveTime, unit, workQueue,
 				handler);
 		log = Logger.getLogger(tag);
 	}
 	@Override
 	public void execute(Runnable r) {
 		if (log.isLoggable(LOG_LEVEL)) {
 			long submitted = System.currentTimeMillis();
 			super.execute(() -> {
 				long started = System.currentTimeMillis();
 				long queued = started - submitted;
 				log.log(LOG_LEVEL, "Queue time " + queued + " ms");
 				r.run();
 				long executing = System.currentTimeMillis() - started;
 				log.log(LOG_LEVEL, "Execution time " + executing + " ms");
 			});
 		} else {
 			super.execute(r);
 		}
 	}
 }
@@ -201,8 +201,7 @@ class ClientHelperImpl implements ClientHelper {
 	public Map<MessageId, BdfDictionary> getMessageMetadataAsDictionary(
 			Transaction txn, GroupId g) throws DbException, FormatException {
 		Map<MessageId, Metadata> raw = db.getMessageMetadata(txn, g);
-		Map<MessageId, BdfDictionary> parsed =
+		Map<MessageId, BdfDictionary> parsed = new HashMap<>(raw.size());
 				new HashMap<MessageId, BdfDictionary>(raw.size());
 		for (Entry<MessageId, Metadata> e : raw.entrySet())
 			parsed.put(e.getKey(), metadataParser.parse(e.getValue()));
 		return parsed;
@@ -229,8 +228,7 @@ class ClientHelperImpl implements ClientHelper {
 			FormatException {
 		Metadata metadata = metadataEncoder.encode(query);
 		Map<MessageId, Metadata> raw = db.getMessageMetadata(txn, g, metadata);
-		Map<MessageId, BdfDictionary> parsed =
+		Map<MessageId, BdfDictionary> parsed = new HashMap<>(raw.size());
 				new HashMap<MessageId, BdfDictionary>(raw.size());
 		for (Entry<MessageId, Metadata> e : raw.entrySet())
 			parsed.put(e.getKey(), metadataParser.parse(e.getValue()));
 		return parsed;
@@ -32,23 +32,25 @@ class ContactGroupFactoryImpl implements ContactGroupFactory {
 	}
 	@Override
-	public Group createLocalGroup(ClientId clientId) {
+	public Group createLocalGroup(ClientId clientId, int clientVersion) {
-		return groupFactory.createGroup(clientId, LOCAL_GROUP_DESCRIPTOR);
+		return groupFactory.createGroup(clientId, clientVersion,
 				LOCAL_GROUP_DESCRIPTOR);
 	}
 	@Override
-	public Group createContactGroup(ClientId clientId, Contact contact) {
+	public Group createContactGroup(ClientId clientId, int clientVersion,
 			Contact contact) {
 		AuthorId local = contact.getLocalAuthorId();
 		AuthorId remote = contact.getAuthor().getId();
 		byte[] descriptor = createGroupDescriptor(local, remote);
-		return groupFactory.createGroup(clientId, descriptor);
+		return groupFactory.createGroup(clientId, clientVersion, descriptor);
 	}
 	@Override
-	public Group createContactGroup(ClientId clientId, AuthorId authorId1,
+	public Group createContactGroup(ClientId clientId, int clientVersion,
-			AuthorId authorId2) {
+			AuthorId authorId1, AuthorId authorId2) {
 		byte[] descriptor = createGroupDescriptor(authorId1, authorId2);
-		return groupFactory.createGroup(clientId, descriptor);
+		return groupFactory.createGroup(clientId, clientVersion, descriptor);
 	}
 	private byte[] createGroupDescriptor(AuthorId local, AuthorId remote) {
@@ -80,7 +80,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	private volatile boolean alice;
 	@Inject
-	public ContactExchangeTaskImpl(DatabaseComponent db,
+	ContactExchangeTaskImpl(DatabaseComponent db,
 			AuthorFactory authorFactory, BdfReaderFactory bdfReaderFactory,
 			BdfWriterFactory bdfWriterFactory, Clock clock,
 			ConnectionManager connectionManager, ContactManager contactManager,
@@ -141,23 +141,27 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		}
 		// Derive the header keys for the transport streams
-		SecretKey aliceHeaderKey = crypto.deriveHeaderKey(masterSecret, true);
+		SecretKey aliceHeaderKey = crypto.deriveKey(ALICE_KEY_LABEL,
-		SecretKey bobHeaderKey = crypto.deriveHeaderKey(masterSecret, false);
+				masterSecret, new byte[] {PROTOCOL_VERSION});
 		SecretKey bobHeaderKey = crypto.deriveKey(BOB_KEY_LABEL, masterSecret,
 				new byte[] {PROTOCOL_VERSION});
 		// Create the readers
 		InputStream streamReader =
-				streamReaderFactory.createInvitationStreamReader(in,
+				streamReaderFactory.createContactExchangeStreamReader(in,
 						alice ? bobHeaderKey : aliceHeaderKey);
 		BdfReader r = bdfReaderFactory.createReader(streamReader);
 		// Create the writers
 		OutputStream streamWriter =
-				streamWriterFactory.createInvitationStreamWriter(out,
+				streamWriterFactory.createContactExchangeStreamWriter(out,
 						alice ? aliceHeaderKey : bobHeaderKey);
 		BdfWriter w = bdfWriterFactory.createWriter(streamWriter);
 		// Derive the nonces to be signed
-		byte[] aliceNonce = crypto.deriveSignatureNonce(masterSecret, true);
+		byte[] aliceNonce = crypto.mac(ALICE_NONCE_LABEL, masterSecret,
-		byte[] bobNonce = crypto.deriveSignatureNonce(masterSecret, false);
+				new byte[] {PROTOCOL_VERSION});
 		byte[] bobNonce = crypto.mac(BOB_NONCE_LABEL, masterSecret,
 				new byte[] {PROTOCOL_VERSION});
 		// Exchange pseudonyms, signed nonces, and timestamps
 		long localTimestamp = clock.currentTimeMillis();
@@ -184,12 +188,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 			// Close the outgoing stream and expect EOF on the incoming stream
 			w.close();
 			if (!r.eof()) LOG.warning("Unexpected data at end of connection");
-		} catch (GeneralSecurityException e) {
+		} catch (GeneralSecurityException | IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			listener.contactExchangeFailed();
 			tryToClose(conn, true);
 			return;
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			listener.contactExchangeFailed();
 			tryToClose(conn, true);
@@ -201,8 +200,8 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		try {
 			// Add the contact
-			ContactId contactId = addContact(remoteAuthor, masterSecret,
+			ContactId contactId = addContact(remoteAuthor, timestamp,
-					timestamp, alice, remoteProperties);
+					remoteProperties);
 			// Reuse the connection as a transport connection
 			connectionManager.manageOutgoingConnection(contactId, transportId,
 					conn);
@@ -276,8 +275,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	private Map<TransportId, TransportProperties> receiveTransportProperties(
 			BdfReader r) throws IOException {
-		Map<TransportId, TransportProperties> remote =
+		Map<TransportId, TransportProperties> remote = new HashMap<>();
 				new HashMap<TransportId, TransportProperties>();
 		r.readListStart();
 		while (!r.hasListEnd()) {
 			r.readListStart();
@@ -300,15 +298,15 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		return remote;
 	}
-	private ContactId addContact(Author remoteAuthor, SecretKey master,
+	private ContactId addContact(Author remoteAuthor, long timestamp,
 			long timestamp, boolean alice,
 			Map<TransportId, TransportProperties> remoteProperties)
 			throws DbException {
 		ContactId contactId;
 		Transaction txn = db.startTransaction(false);
 		try {
 			contactId = contactManager.addContact(txn, remoteAuthor,
-					localAuthor.getId(), master, timestamp, alice, true, true);
+					localAuthor.getId(), masterSecret, timestamp, alice,
 					true, true);
 			transportPropertyManager.addRemoteProperties(txn, contactId,
 					remoteProperties);
 			db.commitTransaction(txn);
@@ -318,8 +316,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		return contactId;
 	}
-	private void tryToClose(DuplexTransportConnection conn,
+	private void tryToClose(DuplexTransportConnection conn, boolean exception) {
 			boolean exception) {
 		try {
 			LOG.info("Closing connection");
 			conn.getReader().dispose(exception, true);
@@ -6,6 +6,7 @@ import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
 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;
@@ -33,8 +34,8 @@ class ContactManagerImpl implements ContactManager {
 	ContactManagerImpl(DatabaseComponent db, KeyManager keyManager) {
 		this.db = db;
 		this.keyManager = keyManager;
-		addHooks = new CopyOnWriteArrayList<AddContactHook>();
+		addHooks = new CopyOnWriteArrayList<>();
-		removeHooks = new CopyOnWriteArrayList<RemoveContactHook>();
+		removeHooks = new CopyOnWriteArrayList<>();
 	}
 	@Override
@@ -88,6 +89,32 @@ class ContactManagerImpl implements ContactManager {
 		return contact;
 	}
 	@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);
 		}
 	}
 	@Override
 	public Contact getContact(Transaction txn, AuthorId remoteAuthorId,
 			AuthorId localAuthorId) throws DbException {
 		Collection<Contact> contacts =
 				db.getContactsByAuthorId(txn, remoteAuthorId);
 		for (Contact c : contacts) {
 			if (c.getLocalAuthorId().equals(localAuthorId)) {
 				return c;
 			}
 		}
 		throw new NoSuchContactException();
 	}
 	@Override
 	public Collection<Contact> getActiveContacts() throws DbException {
 		Collection<Contact> contacts;
@@ -98,7 +125,7 @@ class ContactManagerImpl implements ContactManager {
 		} finally {
 			db.endTransaction(txn);
 		}
-		List<Contact> active = new ArrayList<Contact>(contacts.size());
+		List<Contact> active = new ArrayList<>(contacts.size());
 		for (Contact c : contacts) if (c.isActive()) active.add(c);
 		return active;
 	}
@@ -1,62 +0,0 @@
 package org.briarproject.bramble.crypto;
 import java.security.Provider;
 import java.security.SecureRandom;
 import java.security.SecureRandomSpi;
 /**
 * A {@link SecureRandom} implementation that combines the outputs of two or
 * more other implementations using XOR.
 */
 class CombinedSecureRandom extends SecureRandom {
 	private static final Provider PROVIDER = new CombinedProvider();
 	CombinedSecureRandom(SecureRandom... randoms) {
 		super(new CombinedSecureRandomSpi(randoms), PROVIDER);
 	}
 	private static class CombinedSecureRandomSpi extends SecureRandomSpi {
 		private final SecureRandom[] randoms;
 		private CombinedSecureRandomSpi(SecureRandom... randoms) {
 			if (randoms.length < 2) throw new IllegalArgumentException();
 			this.randoms = randoms;
 		}
 		@Override
 		protected byte[] engineGenerateSeed(int numBytes) {
 			byte[] combined = new byte[numBytes];
 			for (SecureRandom random : randoms) {
 				byte[] b = random.generateSeed(numBytes);
 				int length = Math.min(numBytes, b.length);
 				for (int i = 0; i < length; i++)
 					combined[i] = (byte) (combined[i] ^ b[i]);
 			}
 			return combined;
 		}
 		@Override
 		protected void engineNextBytes(byte[] b) {
 			byte[] temp = new byte[b.length];
 			for (SecureRandom random : randoms) {
 				random.nextBytes(temp);
 				for (int i = 0; i < b.length; i++)
 					b[i] = (byte) (b[i] ^ temp[i]);
 			}
 		}
 		@Override
 		protected void engineSetSeed(byte[] seed) {
 			for (SecureRandom random : randoms) random.setSeed(seed);
 		}
 	}
 	private static class CombinedProvider extends Provider {
 		private CombinedProvider() {
 			super("Combined", 1.0, "");
 		}
 	}
 }
--- a/Show More
+++ b/Show More