Only show Introduction Accept Information if success is still possible

2026-02-13 19:29:06 +01:00 · 2018-04-28 11:45:10 -03:00
350 changed files with 4704 additions and 8650 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -20,7 +20,6 @@ local.properties
 .idea/*
 !.idea/runConfigurations/
 !.idea/codeStyleSettings.xml
 !.idea/codeStyles
 .gradle
 build/
 *.iml
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,31 +1,29 @@
-image: briar/ci-image-android:latest
+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:
  before_script:
    - set -e
    - export GRADLE_USER_HOME=$PWD/.gradle
  cache:
    paths:
      - .gradle/wrapper
      - .gradle/caches
  script:
-    - ./gradlew --no-daemon animalSnifferMain animalSnifferTest
+    - ./gradlew test
    - ./gradlew --no-daemon test
-  after_script:
+after_script:
-    # these file change every time but should not be cached
+    # 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/
 test_reproducible:
  image: briar/reproducer:latest
  script:
    - cd /opt/briar-reproducer
    - ./reproduce.py ${CI_COMMIT_REF_NAME}
  only:
    - tags
--- a/.idea/codeStyles/Project.xml
+++ b/.idea/codeStyles/Project.xml
@@ -1,261 +0,0 @@
 <component name="ProjectCodeStyleConfiguration">
  <code_scheme name="Project" version="173">
    <option name="RIGHT_MARGIN" value="100" />
    <AndroidXmlCodeStyleSettings>
      <option name="USE_CUSTOM_SETTINGS" value="true" />
    </AndroidXmlCodeStyleSettings>
    <JavaCodeStyleSettings>
      <option name="ANNOTATION_PARAMETER_WRAP" value="1" />
      <option name="CLASS_COUNT_TO_USE_IMPORT_ON_DEMAND" value="99" />
      <option name="NAMES_COUNT_TO_USE_IMPORT_ON_DEMAND" value="99" />
      <option name="PACKAGES_TO_USE_IMPORT_ON_DEMAND">
        <value />
      </option>
      <option name="IMPORT_LAYOUT_TABLE">
        <value>
          <package name="android" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="com" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="junit" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="net" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="org" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="java" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="javax" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="" withSubpackages="true" static="false" />
          <emptyLine />
          <package name="" withSubpackages="true" static="true" />
          <emptyLine />
        </value>
      </option>
      <option name="JD_ALIGN_PARAM_COMMENTS" value="false" />
      <option name="JD_ALIGN_EXCEPTION_COMMENTS" value="false" />
    </JavaCodeStyleSettings>
    <Objective-C-extensions>
      <file>
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Import" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Macro" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Typedef" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Enum" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Constant" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Global" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Struct" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="FunctionPredecl" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Function" />
      </file>
      <class>
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Property" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Synthesize" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="InitMethod" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="StaticMethod" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="InstanceMethod" />
        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="DeallocMethod" />
      </class>
      <extensions>
        <pair source="cpp" header="h" fileNamingConvention="NONE" />
        <pair source="c" header="h" fileNamingConvention="NONE" />
      </extensions>
    </Objective-C-extensions>
    <XML>
      <option name="XML_LEGACY_SETTINGS_IMPORTED" value="true" />
    </XML>
    <codeStyleSettings language="Groovy">
      <indentOptions>
        <option name="USE_TAB_CHARACTER" value="true" />
        <option name="SMART_TABS" value="true" />
      </indentOptions>
    </codeStyleSettings>
    <codeStyleSettings language="JAVA">
      <option name="RIGHT_MARGIN" value="80" />
      <option name="ALIGN_MULTILINE_PARAMETERS" value="false" />
      <option name="ALIGN_MULTILINE_RESOURCES" value="false" />
      <option name="ALIGN_MULTILINE_FOR" value="false" />
      <option name="SPACE_BEFORE_ARRAY_INITIALIZER_LBRACE" value="true" />
      <option name="CALL_PARAMETERS_WRAP" value="1" />
      <option name="METHOD_PARAMETERS_WRAP" value="1" />
      <option name="RESOURCE_LIST_WRAP" value="1" />
      <option name="EXTENDS_LIST_WRAP" value="1" />
      <option name="THROWS_LIST_WRAP" value="1" />
      <option name="EXTENDS_KEYWORD_WRAP" value="1" />
      <option name="THROWS_KEYWORD_WRAP" value="1" />
      <option name="METHOD_CALL_CHAIN_WRAP" value="1" />
      <option name="BINARY_OPERATION_WRAP" value="1" />
      <option name="TERNARY_OPERATION_WRAP" value="1" />
      <option name="FOR_STATEMENT_WRAP" value="1" />
      <option name="ARRAY_INITIALIZER_WRAP" value="1" />
      <option name="ASSIGNMENT_WRAP" value="1" />
      <option name="ASSERT_STATEMENT_WRAP" value="1" />
      <option name="PARAMETER_ANNOTATION_WRAP" value="1" />
      <option name="VARIABLE_ANNOTATION_WRAP" value="1" />
      <option name="ENUM_CONSTANTS_WRAP" value="1" />
      <indentOptions>
        <option name="USE_TAB_CHARACTER" value="true" />
        <option name="SMART_TABS" value="true" />
      </indentOptions>
    </codeStyleSettings>
    <codeStyleSettings language="XML">
      <option name="FORCE_REARRANGE_MODE" value="1" />
      <indentOptions>
        <option name="CONTINUATION_INDENT_SIZE" value="4" />
        <option name="USE_TAB_CHARACTER" value="true" />
        <option name="SMART_TABS" value="true" />
      </indentOptions>
      <arrangement>
        <rules>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>xmlns:android</NAME>
                  <XML_NAMESPACE>Namespace:</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>xmlns:.*</NAME>
                  <XML_NAMESPACE>Namespace:</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:id</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:name</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>name</NAME>
                  <XML_NAMESPACE>^$</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>style</NAME>
                  <XML_NAMESPACE>^$</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*</NAME>
                  <XML_NAMESPACE>^$</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:layout_width</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:layout_height</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:layout_.*</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:width</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*:height</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*</NAME>
                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
          <section>
            <rule>
              <match>
                <AND>
                  <NAME>.*</NAME>
                  <XML_NAMESPACE>.*</XML_NAMESPACE>
                </AND>
              </match>
              <order>BY_NAME</order>
            </rule>
          </section>
        </rules>
      </arrangement>
    </codeStyleSettings>
  </code_scheme>
 </component>
--- a/.idea/codeStyles/codeStyleConfig.xml
+++ b/.idea/codeStyles/codeStyleConfig.xml
@@ -1,5 +0,0 @@
 <component name="ProjectCodeStyleConfiguration">
  <state>
    <option name="USE_PER_PROJECT_SETTINGS" value="true" />
  </state>
 </component>
--- a/bramble-android/build.gradle
+++ b/bramble-android/build.gradle
@@ -1,15 +1,21 @@
 import de.undercouch.gradle.tasks.download.Download
 import de.undercouch.gradle.tasks.download.Verify
 import java.security.NoSuchAlgorithmException
 apply plugin: 'com.android.library'
 apply plugin: 'witness'
 apply plugin: 'de.undercouch.download'
 android {
 	compileSdkVersion 27
-	buildToolsVersion '27.0.3'
+	buildToolsVersion '26.0.2'
 	defaultConfig {
 		minSdkVersion 14
 		targetSdkVersion 26
-		versionCode 10005
+		versionCode 1700
-		versionName "1.0.5"
+		versionName "0.17.0"
 		consumerProguardFiles 'proguard-rules.txt'
 	}
@@ -19,14 +25,9 @@ android {
 	}
 }
 configurations {
 	tor
 }
 dependencies {
 	implementation project(path: ':bramble-core', configuration: 'default')
-	implementation 'org.briarproject:jtorctl:0.3'
+	implementation fileTree(dir: 'libs', include: '*.jar')
 	tor 'org.briarproject:tor-android:0.2.9.15@zip'
 	annotationProcessor 'com.google.dagger:dagger-compiler:2.0.2'
@@ -35,87 +36,101 @@ dependencies {
 dependencyVerification {
 	verify = [
-			'com.android.tools.analytics-library:protos:26.1.2:protos-26.1.2.jar:52672a0b42b572a06aecc3535d5068eb46c0e15d129b9f1085d3c16a1da5cdbb',
+			'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
 			'com.android.tools.analytics-library:shared:26.1.2:shared-26.1.2.jar:5c7e0eda18c6f87feeb83628c707e8aaa3298b41fb72e38efe31ad1675f9e8e9',
 			'com.android.tools.analytics-library:tracker:26.1.2:tracker-26.1.2.jar:06f97aa0adf44ffb06f8681c6a79d9be153a08f61d21eddc42b8d3db96df4282',
 			'com.android.tools.build:apksig:3.1.2:apksig-3.1.2.jar:40696a4559124d1d57873d208857eee059d48859239d569c7d18374ac644a8be',
 			'com.android.tools.build:builder-model:3.1.2:builder-model-3.1.2.jar:d49bfa2a135c9562b6ca7aa4342036cfa1582c7074c2d1d93d1dae8b3a134e17',
 			'com.android.tools.build:builder-test-api:3.1.2:builder-test-api-3.1.2.jar:dfe2a50b740d41b11189101062434d4283d18647e89a492ad51710c719363e9f',
 			'com.android.tools.build:builder:3.1.2:builder-3.1.2.jar:b60f825a42e2efe8433619fbc759f3d9effecab718279048d36881188ceb1d14',
 			'com.android.tools.build:gradle-api:3.1.2:gradle-api-3.1.2.jar:e58bcc5b893e4583ab0f5c8ef89c4dbcce202b405a9d7fcc116d21e5357d4893',
 			'com.android.tools.build:manifest-merger:26.1.2:manifest-merger-26.1.2.jar:9c61c27ea5266573107b954acf1216d398f4d7e7ae6fad6409d6b2b767eb091c',
 			'com.android.tools.ddms:ddmlib:26.1.2:ddmlib-26.1.2.jar:18a2a5fbef36882f07d03c2b9e59eba05cf8248177bf5cbff736e4b582804c44',
 			'com.android.tools.external.com-intellij:intellij-core:26.1.2:intellij-core-26.1.2.jar:37c5acf279f1ae3e85b1a5be3c9f15f43bde7b08f978eefefffb9c4035760c52',
 			'com.android.tools.external.com-intellij:kotlin-compiler:26.1.2:kotlin-compiler-26.1.2.jar:152df0bee7580326c77316b669a9d96e3b09efb1d45f545dce4147271b0b8944',
 			'com.android.tools.external.org-jetbrains:uast:26.1.2:uast-26.1.2.jar:02d39582206d3f5fc0a6cb18bfd9e8b9f9c1acb805ec6dac08b4e3a56849d279',
 			'com.android.tools.layoutlib:layoutlib-api:26.1.2:layoutlib-api-26.1.2.jar:20220039fcc7d799f928153beff862e704457c0f55ab44258f3745ebeb662b4f',
 			'com.android.tools.lint:lint-api:26.1.2:lint-api-26.1.2.jar:e1d5b62b870a7c566e9877a6b96b27784a4d713f8caa07fdcb4705d47a40a1d9',
 			'com.android.tools.lint:lint-checks:26.1.2:lint-checks-26.1.2.jar:211e2afd58504372385d71b1e5be982c2b5121ab6fee1c04ddabeb75a8729e07',
 			'com.android.tools.lint:lint-gradle-api:26.1.2:lint-gradle-api-26.1.2.jar:71284f2a8b03c3e55c94511c9eb36f8184fbb85324325fc6b78abf5183f03d90',
 			'com.android.tools.lint:lint-gradle:26.1.2:lint-gradle-26.1.2.jar:855f0c82b7fc690df1b7319c0774f7517f7f8f5dd4eee1f6077dcf50e07c6240',
 			'com.android.tools.lint:lint-kotlin:26.1.2:lint-kotlin-26.1.2.jar:1e591f70bcbbc11569720a9bbcca2bc1f3d4f789f01f40f642848d920643d484',
 			'com.android.tools.lint:lint:26.1.2:lint-26.1.2.jar:93736c62e9f1976998c2b4aa716aea0734cdb162d05502f4af7292654aedb182',
 			'com.android.tools:annotations:26.1.2:annotations-26.1.2.jar:72773dcaf5c4ccca828e3c8467f1b78a8a00b3cc5f8ad1aab88fcf9379928018',
 			'com.android.tools:common:26.1.2:common-26.1.2.jar:ea4320f0c17dcbc4491896bb705c4d25ec08bd62ef02ab0579fe154e75e788e6',
 			'com.android.tools:dvlib:26.1.2:dvlib-26.1.2.jar:1187aa4fb666595c96c4deb6bc0e0f4b7e396bde9f6243330b49a232946130ea',
 			'com.android.tools:repository:26.1.2:repository-26.1.2.jar:8b86e512ad6d32bd76989451eefe2b271f5efce6d4d65ecb173afaf14606e01a',
 			'com.android.tools:sdk-common:26.1.2:sdk-common-26.1.2.jar:23584720a60a21cdcb5b1ec10269e3013789d6805d153cc696c39ec7ce251896',
 			'com.android.tools:sdklib:26.1.2:sdklib-26.1.2.jar:d3870fafc59ab8efa70d3f9649f40ee299c8ec5b58377b06e8853d7272a5bf4e',
 			'com.google.code.findbugs:jsr305:1.3.9:jsr305-1.3.9.jar:905721a0eea90a81534abb7ee6ef4ea2e5e645fa1def0a5cd88402df1b46c9ed',
 			'com.google.code.gson:gson:2.7:gson-2.7.jar:2d43eb5ea9e133d2ee2405cc14f5ee08951b8361302fdd93494a3a997b508d32',
 			'com.google.dagger:dagger-compiler:2.0.2:dagger-compiler-2.0.2.jar:b74bc9de063dd4c6400b232231f2ef5056145b8fbecbf5382012007dd1c071b3',
 			'com.google.dagger:dagger-producers:2.0-beta:dagger-producers-2.0-beta.jar:99ec15e8a0507ba569e7655bc1165ee5e5ca5aa914b3c8f7e2c2458f724edd6b',
 			'com.google.dagger:dagger:2.0.2:dagger-2.0.2.jar:84c0282ed8be73a29e0475d639da030b55dee72369e58dd35ae7d4fe6243dcf9',
 			'com.google.errorprone:error_prone_annotations:2.0.18:error_prone_annotations-2.0.18.jar:cb4cfad870bf563a07199f3ebea5763f0dec440fcda0b318640b1feaa788656b',
 			'com.google.guava:guava:18.0:guava-18.0.jar:d664fbfc03d2e5ce9cab2a44fb01f1d0bf9dfebeccc1a473b1f9ea31f79f6f99',
-			'com.google.guava:guava:22.0:guava-22.0.jar:1158e94c7de4da480873f0b4ab4a1da14c0d23d4b1902cc94a58a6f0f9ab579e',
+			'com.h2database:h2:1.4.192:h2-1.4.192.jar:225b22e9857235c46c93861410b60b8c81c10dc8985f4faf188985ba5445126c',
-			'com.google.j2objc:j2objc-annotations:1.1:j2objc-annotations-1.1.jar:40ceb7157feb263949e0f503fe5f71689333a621021aa20ce0d0acee3badaa0f',
+			'com.madgag.spongycastle:core:1.58.0.0:core-1.58.0.0.jar:199617dd5698c5a9312b898c0a4cec7ce9dd8649d07f65d91629f58229d72728',
 			'com.google.jimfs:jimfs:1.1:jimfs-1.1.jar:c4828e28d7c0a930af9387510b3bada7daa5c04d7c25a75c7b8b081f1c257ddd',
 			'com.google.protobuf:protobuf-java:3.4.0:protobuf-java-3.4.0.jar:dce7e66b32456a1b1198da0caff3a8acb71548658391e798c79369241e6490a4',
 			'com.googlecode.json-simple:json-simple:1.1:json-simple-1.1.jar:2d9484f4c649f708f47f9a479465fc729770ee65617dca3011836602264f6439',
 			'com.squareup:javawriter:2.5.0:javawriter-2.5.0.jar:fcfb09fb0ea0aa97d3cfe7ea792398081348e468f126b3603cb3803f240197f0',
 			'com.sun.activation:javax.activation:1.2.0:javax.activation-1.2.0.jar:993302b16cd7056f21e779cc577d175a810bb4900ef73cd8fbf2b50f928ba9ce',
 			'com.sun.istack:istack-commons-runtime:2.21:istack-commons-runtime-2.21.jar:c33e67a0807095f02a0e2da139412dd7c4f9cc1a4c054b3e434f96831ba950f4',
 			'com.sun.xml.fastinfoset:FastInfoset:1.2.13:FastInfoset-1.2.13.jar:27a77db909f3c2833c0b1a37c55af1db06045118ad2eed96ce567b6632bce038',
 			'commons-codec:commons-codec:1.6:commons-codec-1.6.jar:54b34e941b8e1414bd3e40d736efd3481772dc26db3296f6aa45cec9f6203d86',
 			'commons-logging:commons-logging:1.1.1:commons-logging-1.1.1.jar:ce6f913cad1f0db3aad70186d65c5bc7ffcc9a99e3fe8e0b137312819f7c362f',
 			'it.unimi.dsi:fastutil:7.2.0:fastutil-7.2.0.jar:74fa208043740642f7e6eb09faba15965218ad2f50ce3020efb100136e4b591c',
 			'javax.annotation:jsr250-api:1.0:jsr250-api-1.0.jar:a1a922d0d9b6d183ed3800dfac01d1e1eb159f0e8c6f94736931c1def54a941f',
 			'javax.inject:javax.inject:1:javax.inject-1.jar:91c77044a50c481636c32d916fd89c9118a72195390452c81065080f957de7ff',
-			'javax.xml.bind:jaxb-api:2.2.12-b140109.1041:jaxb-api-2.2.12-b140109.1041.jar:b5e60cd8b7b5ff01ce4a74c5dd008f4fbd14ced3495d0b47b85cfedc182211f2',
+			'net.i2p.crypto:eddsa:0.2.0:eddsa-0.2.0.jar:a7cb1b85c16e2f0730b9204106929a1d9aaae1df728adc7041a8b8b605692140',
-			'net.sf.jopt-simple:jopt-simple:4.9:jopt-simple-4.9.jar:26c5856e954b5f864db76f13b86919b59c6eecf9fd930b96baa8884626baf2f5',
+			'org.bitlet:weupnp:0.1.4:weupnp-0.1.4.jar:88df7e6504929d00bdb832863761385c68ab92af945b04f0770b126270a444fb',
-			'net.sf.kxml:kxml2:2.3.0:kxml2-2.3.0.jar:f264dd9f79a1fde10ce5ecc53221eff24be4c9331c830b7d52f2f08a7b633de2',
+			'org.jacoco:org.jacoco.agent:0.7.4.201502262128:org.jacoco.agent-0.7.4.201502262128-runtime.jar:e357a0f1d573c2f702a273992b1b6cb661734f66311854efb3778a888515c5b5',
-			'org.apache.commons:commons-compress:1.12:commons-compress-1.12.jar:2c1542faf343185b7cab9c3d55c8ae5471d6d095d3887a4adefdbdf2984dc0b6',
+			'org.jacoco:org.jacoco.agent:0.7.4.201502262128:org.jacoco.agent-0.7.4.201502262128.jar:47b4bec6df11a1118da3953da8b9fa1e7079d6fec857faa1a3cf912e53a6fd4e',
-			'org.apache.httpcomponents:httpclient:4.2.6:httpclient-4.2.6.jar:362e9324ee7c697e21279e20077b52737ddef3f1b2c1a7abe5ad34b465145550',
+			'org.jacoco:org.jacoco.ant:0.7.4.201502262128:org.jacoco.ant-0.7.4.201502262128.jar:013ce2a68ba57a3c59215ae0dec4df3498c078062a38c3b94c841fc14450f283',
-			'org.apache.httpcomponents:httpcore:4.2.5:httpcore-4.2.5.jar:e5e82da4cc66c8d917bbf743e3c0752efe8522735e7fc9dbddb65bccea81cfe9',
+			'org.jacoco:org.jacoco.core:0.7.4.201502262128:org.jacoco.core-0.7.4.201502262128.jar:ec4c74554312fac5116350164786f91b35c9e082fa4ea598bfa42b5db05d7abb',
-			'org.apache.httpcomponents:httpmime:4.1:httpmime-4.1.jar:31629566148e8a47688ae43b420abc3ecd783ed15b33bebc00824bf24c9b15aa',
+			'org.jacoco:org.jacoco.report:0.7.4.201502262128:org.jacoco.report-0.7.4.201502262128.jar:7a3554c605e088e7e323b1084656243f0444fa353e2f2dee1f1a4204eb64ff09',
-			'org.bouncycastle:bcpkix-jdk15on:1.56:bcpkix-jdk15on-1.56.jar:7043dee4e9e7175e93e0b36f45b1ec1ecb893c5f755667e8b916eb8dd201c6ca',
+			'org.ow2.asm:asm-debug-all:5.0.1:asm-debug-all-5.0.1.jar:4734de5b515a454b0096db6971fb068e5f70e6f10bbee2b3bd2fdfe5d978ed57',
 			'org.bouncycastle:bcprov-jdk15on:1.56:bcprov-jdk15on-1.56.jar:963e1ee14f808ffb99897d848ddcdb28fa91ddda867eb18d303e82728f878349',
 			'org.briarproject:jtorctl:0.3:jtorctl-0.3.jar:f2939238a097898998432effe93b0334d97a787972ab3a91a8973a1d309fc864',
 			'org.briarproject:tor-android:0.2.9.15:tor-android-0.2.9.15.zip:34a6474ee219ffa52e0f3393e917dda6ed03d320b02247d4fa5075aa4094ee6d',
 			'org.codehaus.groovy:groovy-all:2.4.12:groovy-all-2.4.12.jar:6a56af4bd48903d56bec62821876cadefafd007360cc6bd0d8f7aa8d72b38be4',
 			'org.codehaus.mojo:animal-sniffer-annotations:1.14:animal-sniffer-annotations-1.14.jar:2068320bd6bad744c3673ab048f67e30bef8f518996fa380033556600669905d',
 			'org.glassfish.jaxb:jaxb-core:2.2.11:jaxb-core-2.2.11.jar:37bcaee8ebb04362c8352a5bf6221b86967ecdab5164c696b10b9a2bb587b2aa',
 			'org.glassfish.jaxb:jaxb-runtime:2.2.11:jaxb-runtime-2.2.11.jar:a874f2351cfba8e2946be3002d10c18a6da8f21b52ba2acf52f2b85d5520ed70',
 			'org.glassfish.jaxb:txw2:2.2.11:txw2-2.2.11.jar:272a3ccad45a4511351920cd2a8633c53cab8d5220c7a92954da5526bb5eafea',
 			'org.jetbrains.kotlin:kotlin-reflect:1.2.0:kotlin-reflect-1.2.0.jar:4f48a872bad6e4d9c053f4ad610d11e4012ad7e58dc19a03dd5eb811f36069dd',
 			'org.jetbrains.kotlin:kotlin-stdlib-jre7:1.2.0:kotlin-stdlib-jre7-1.2.0.jar:c7a20fb951d437797afe8980aff6c1e5a03f310c661ba58ba1d4fa90cb0f2926',
 			'org.jetbrains.kotlin:kotlin-stdlib-jre8:1.2.0:kotlin-stdlib-jre8-1.2.0.jar:633524eee6ef1941f7cb1dab7ee3927b0a221ceee9047aeb5515f4cbb990c82a',
 			'org.jetbrains.kotlin:kotlin-stdlib:1.2.0:kotlin-stdlib-1.2.0.jar:05cfd9f5ac0b41910703a8925f7211a495909b27a2ffdd1c5106f1689aeafcd4',
 			'org.jetbrains.trove4j:trove4j:20160824:trove4j-20160824.jar:1917871c8deb468307a584680c87a44572f5a8b0b98c6d397fc0f5f86596dbe7',
 			'org.jetbrains:annotations:13.0:annotations-13.0.jar:ace2a10dc8e2d5fd34925ecac03e4988b2c0f851650c94b8cef49ba1bd111478',
 			'org.jvnet.staxex:stax-ex:1.7.7:stax-ex-1.7.7.jar:a31ff7d77163c0deb09e7fee59ad35ae44c2cee2cc8552a116ccd1583d813fb4',
 			'org.ow2.asm:asm-analysis:5.1:asm-analysis-5.1.jar:a34658f5c5de4b573eef21131cc32cc25f7b66407944f312b28ec2e56abb1fa9',
 			'org.ow2.asm:asm-commons:5.1:asm-commons-5.1.jar:97b3786e1f55e74bddf8ad102bf50e33bbcbc1f6b7fd7b36f0bbbb25cd4981be',
 			'org.ow2.asm:asm-tree:5.1:asm-tree-5.1.jar:c0de2bbc4cb8297419659813ecd4ed1d077ed1dd5c1f5544cc5143e493e84c10',
 			'org.ow2.asm:asm-util:5.1:asm-util-5.1.jar:ee032c39ae5e3cd099148fbba9a2124f9ed613e5cb93e03ee0fa8808ce364040',
 			'org.ow2.asm:asm:5.1:asm-5.1.jar:d2da399a9967c69f0a21739256fa79d284222c223082cacadc17372244764b54',
 	]
 }
-project.afterEvaluate {
+ext.torBinaryDir = 'src/main/res/raw'
-	copy {
+ext.torVersion = '0.2.9.14'
-		from configurations.tor.collect { zipTree(it) }
+ext.geoipVersion = '2017-11-06'
-		into 'src/main/res/raw'
+ext.torDownloadUrl = 'https://briarproject.org/build/'
 def torBinaries = [
 		"tor_arm"    : '1710ea6c47b7f4c1a88bdf4858c7893837635db10e8866854eed8d61629f50e8',
 		"tor_arm_pie": '974e6949507db8fa2ea45231817c2c3677ed4ccf5488a2252317d744b0be1917',
 		"tor_x86"    : '3a5e45b3f051fcda9353b098b7086e762ffe7ba9242f7d7c8bf6523faaa8b1e9',
 		"tor_x86_pie": 'd1d96d8ce1a4b68accf04850185780d10cd5563d3552f7e1f040f8ca32cb4e51',
 		"geoip"      : '8239b98374493529a29096e45fc5877d4d6fdad0146ad8380b291f90d61484ea'
 ]
 def verifyOrDeleteBinary(name, chksum, alreadyVerified) {
 	return tasks.create("verifyOrDeleteBinary${name}", VerifyOrDelete) {
 		src "${torBinaryDir}/${name}.zip"
 		algorithm 'SHA-256'
 		checksum chksum
 		result alreadyVerified
 		onlyIf {
 			src.exists()
 		}
 	}
 }
 def downloadBinary(name, chksum, alreadyVerified) {
 	return tasks.create([
 			name: "downloadBinary${name}",
 			type: Download,
 			dependsOn: verifyOrDeleteBinary(name, chksum, alreadyVerified)]) {
 		src "${torDownloadUrl}${name}.zip"
 				.replace('tor_', "tor-${torVersion}-")
 				.replace('geoip', "geoip-${geoipVersion}")
 				.replaceAll('_', '-')
 		dest "${torBinaryDir}/${name}.zip"
 		onlyIf {
 			!dest.exists()
 		}
 	}
 }
 def verifyBinary(name, chksum) {
 	boolean[] alreadyVerified = [false]
 	return tasks.create([
 			name     : "verifyBinary${name}",
 			type     : Verify,
 			dependsOn: downloadBinary(name, chksum, alreadyVerified)]) {
 		src "${torBinaryDir}/${name}.zip"
 		algorithm 'SHA-256'
 		checksum chksum
 		onlyIf {
 			!alreadyVerified[0]
 		}
 	}
 }
 project.afterEvaluate {
 	torBinaries.every { name, checksum ->
 		preBuild.dependsOn.add(verifyBinary(name, checksum))
 	}
 }
 class VerifyOrDelete extends Verify {
 	boolean[] result
 	@TaskAction
 	@Override
 	void verify() throws IOException, NoSuchAlgorithmException {
 		try {
 			super.verify()
 			result[0] = true
 		} catch (Exception e) {
 			println "${src} failed verification - deleting"
 			src.delete()
 		}
 	}
 }
--- a/bramble-android/libs/jtorctl-briar.jar
+++ b/bramble-android/libs/jtorctl-briar.jar
--- a/bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/BrambleAndroidModule.java
@@ -1,10 +1,12 @@
 package org.briarproject.bramble;
 import org.briarproject.bramble.plugin.AndroidPluginModule;
 import org.briarproject.bramble.system.AndroidSystemModule;
 import dagger.Module;
@Module(includes = {
 		AndroidPluginModule.class,
 		AndroidSystemModule.class
 })
 public class BrambleAndroidModule {
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/AndroidPluginModule.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/AndroidPluginModule.java
@@ -0,0 +1,69 @@
 package org.briarproject.bramble.plugin;
 import android.app.Application;
 import android.content.Context;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.BackoffFactory;
 import org.briarproject.bramble.api.plugin.PluginConfig;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPluginFactory;
 import org.briarproject.bramble.api.plugin.simplex.SimplexPluginFactory;
 import org.briarproject.bramble.api.reporting.DevReporter;
 import org.briarproject.bramble.api.system.AndroidExecutor;
 import org.briarproject.bramble.api.system.LocationUtils;
 import org.briarproject.bramble.api.system.Scheduler;
 import org.briarproject.bramble.plugin.bluetooth.AndroidBluetoothPluginFactory;
 import org.briarproject.bramble.plugin.tcp.AndroidLanTcpPluginFactory;
 import org.briarproject.bramble.plugin.tor.TorPluginFactory;
 import java.security.SecureRandom;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ScheduledExecutorService;
 import javax.net.SocketFactory;
 import dagger.Module;
 import dagger.Provides;
@Module
 public class AndroidPluginModule {
 	@Provides
 	PluginConfig providePluginConfig(@IoExecutor Executor ioExecutor,
 			@Scheduler ScheduledExecutorService scheduler,
 			AndroidExecutor androidExecutor, SecureRandom random,
 			SocketFactory torSocketFactory, BackoffFactory backoffFactory,
 			Application app, LocationUtils locationUtils, DevReporter reporter,
 			EventBus eventBus) {
 		Context appContext = app.getApplicationContext();
 		DuplexPluginFactory bluetooth =
 				new AndroidBluetoothPluginFactory(ioExecutor, androidExecutor,
 						appContext, random, eventBus, backoffFactory);
 		DuplexPluginFactory tor = new TorPluginFactory(ioExecutor, scheduler,
 				appContext, locationUtils, reporter, eventBus,
 				torSocketFactory, backoffFactory);
 		DuplexPluginFactory lan = new AndroidLanTcpPluginFactory(ioExecutor,
 				scheduler, backoffFactory, appContext);
 		Collection<DuplexPluginFactory> duplex =
 				Arrays.asList(bluetooth, tor, lan);
 		@NotNullByDefault
 		PluginConfig pluginConfig = new PluginConfig() {
 			@Override
 			public Collection<DuplexPluginFactory> getDuplexFactories() {
 				return duplex;
 			}
 			@Override
 			public Collection<SimplexPluginFactory> getSimplexFactories() {
 				return Collections.emptyList();
 			}
 		};
 		return pluginConfig;
 	}
 }
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPlugin.java
@@ -55,12 +55,10 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 	// Non-null if the plugin started successfully
 	private volatile BluetoothAdapter adapter = null;
-	AndroidBluetoothPlugin(BluetoothConnectionLimiter connectionLimiter,
+	AndroidBluetoothPlugin(Executor ioExecutor, AndroidExecutor androidExecutor,
 			Executor ioExecutor, AndroidExecutor androidExecutor,
 			Context appContext, SecureRandom secureRandom, Backoff backoff,
 			DuplexPluginCallback callback, int maxLatency) {
-		super(connectionLimiter, ioExecutor, secureRandom, backoff, callback,
+		super(ioExecutor, secureRandom, backoff, callback, maxLatency);
 				maxLatency);
 		this.androidExecutor = androidExecutor;
 		this.appContext = appContext;
 	}
@@ -156,8 +154,7 @@ class AndroidBluetoothPlugin extends BluetoothPlugin<BluetoothServerSocket> {
 	}
 	private DuplexTransportConnection wrapSocket(BluetoothSocket s) {
-		return new AndroidBluetoothTransportConnection(this,
+		return new AndroidBluetoothTransportConnection(this, s);
 				connectionLimiter, s);
 	}
 	@Override
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothPluginFactory.java
@@ -59,13 +59,11 @@ public class AndroidBluetoothPluginFactory implements DuplexPluginFactory {
 	@Override
 	public DuplexPlugin createPlugin(DuplexPluginCallback callback) {
 		BluetoothConnectionLimiter connectionLimiter =
 				new BluetoothConnectionLimiterImpl();
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
-		AndroidBluetoothPlugin plugin = new AndroidBluetoothPlugin(
+		AndroidBluetoothPlugin plugin = new AndroidBluetoothPlugin(ioExecutor,
-				connectionLimiter, ioExecutor, androidExecutor, appContext,
+				androidExecutor, appContext, secureRandom, backoff, callback,
-				secureRandom, backoff, callback, MAX_LATENCY);
+				MAX_LATENCY);
 		eventBus.addListener(plugin);
 		return plugin;
 	}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothTransportConnection.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/bluetooth/AndroidBluetoothTransportConnection.java
@@ -14,14 +14,10 @@ import java.io.OutputStream;
 class AndroidBluetoothTransportConnection
 		extends AbstractDuplexTransportConnection {
 	private final BluetoothConnectionLimiter connectionManager;
 	private final BluetoothSocket socket;
-	AndroidBluetoothTransportConnection(Plugin plugin,
+	AndroidBluetoothTransportConnection(Plugin plugin, BluetoothSocket socket) {
 			BluetoothConnectionLimiter connectionManager,
 			BluetoothSocket socket) {
 		super(plugin);
 		this.connectionManager = connectionManager;
 		this.socket = socket;
 	}
@@ -37,10 +33,6 @@ class AndroidBluetoothTransportConnection
 	@Override
 	protected void closeConnection(boolean exception) throws IOException {
-		try {
+		socket.close();
 			socket.close();
 		} finally {
 			connectionManager.connectionClosed(this);
 		}
 	}
 }
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPlugin.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPlugin.java
@@ -32,9 +32,11 @@ 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.properties.TransportProperties;
 import org.briarproject.bramble.api.reporting.DevReporter;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.settings.event.SettingsUpdatedEvent;
 import org.briarproject.bramble.api.system.LocationUtils;
 import org.briarproject.bramble.util.AndroidUtils;
 import org.briarproject.bramble.util.IoUtils;
 import org.briarproject.bramble.util.StringUtils;
@@ -50,6 +52,7 @@ import java.net.InetSocketAddress;
 import java.net.ServerSocket;
 import java.net.Socket;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
@@ -111,6 +114,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	private final ScheduledExecutorService scheduler;
 	private final Context appContext;
 	private final LocationUtils locationUtils;
 	private final DevReporter reporter;
 	private final SocketFactory torSocketFactory;
 	private final Backoff backoff;
 	private final DuplexPluginCallback callback;
@@ -132,13 +136,14 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	TorPlugin(Executor ioExecutor, ScheduledExecutorService scheduler,
 			Context appContext, LocationUtils locationUtils,
-			SocketFactory torSocketFactory, Backoff backoff,
+			DevReporter reporter, SocketFactory torSocketFactory,
-			DuplexPluginCallback callback, String architecture,
+			Backoff backoff, DuplexPluginCallback callback,
-			int maxLatency, int maxIdleTime) {
+			String architecture, int maxLatency, int maxIdleTime) {
 		this.ioExecutor = ioExecutor;
 		this.scheduler = scheduler;
 		this.appContext = appContext;
 		this.locationUtils = locationUtils;
 		this.reporter = reporter;
 		this.torSocketFactory = torSocketFactory;
 		this.backoff = backoff;
 		this.callback = callback;
@@ -333,7 +338,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		return zin;
 	}
-	private InputStream getConfigInputStream() {
+	private InputStream getConfigInputStream() throws IOException {
 		int resId = getResourceId("torrc");
 		return appContext.getResources().openRawResource(resId);
 	}
@@ -384,6 +389,14 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		}
 	}
 	private void sendDevReports() {
 		ioExecutor.execute(() -> {
 			// TODO: Trigger this with a TransportEnabledEvent
 			File reportDir = AndroidUtils.getReportDir(appContext);
 			reporter.sendReports(reportDir);
 		});
 	}
 	private void bind() {
 		ioExecutor.execute(() -> {
 			// If there's already a port number stored in config, reuse it
@@ -498,7 +511,7 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	@Override
-	public void stop() {
+	public void stop() throws PluginException {
 		running = false;
 		tryToClose(socket);
 		if (networkStateReceiver != null)
@@ -532,16 +545,20 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	@Override
-	public void poll(Map<ContactId, TransportProperties> contacts) {
+	public void poll(Collection<ContactId> connected) {
 		if (!isRunning()) return;
 		backoff.increment();
-		for (Entry<ContactId, TransportProperties> e : contacts.entrySet()) {
+		Map<ContactId, TransportProperties> remote =
-			connectAndCallBack(e.getKey(), e.getValue());
+				callback.getRemoteProperties();
 		for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
 			ContactId c = e.getKey();
 			if (!connected.contains(c)) connectAndCallBack(c, e.getValue());
 		}
 	}
 	private void connectAndCallBack(ContactId c, TransportProperties p) {
 		ioExecutor.execute(() -> {
 			if (!isRunning()) return;
 			DuplexTransportConnection d = createConnection(p);
 			if (d != null) {
 				backoff.reset();
@@ -551,8 +568,13 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 	}
 	@Override
-	public DuplexTransportConnection createConnection(TransportProperties p) {
+	public DuplexTransportConnection createConnection(ContactId c) {
 		if (!isRunning()) return null;
 		return createConnection(callback.getRemoteProperties(c));
 	}
 	@Nullable
 	private DuplexTransportConnection createConnection(TransportProperties p) {
 		String onion = p.get(PROP_ONION);
 		if (StringUtils.isNullOrEmpty(onion)) return null;
 		if (!ONION.matcher(onion).matches()) {
@@ -602,7 +624,10 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 				connectionStatus.getAndSetCircuitBuilt()) {
 			LOG.info("First circuit built");
 			backoff.reset();
-			if (isRunning()) callback.transportEnabled();
+			if (isRunning()) {
 				sendDevReports();
 				callback.transportEnabled();
 			}
 		}
 	}
@@ -631,7 +656,10 @@ class TorPlugin implements DuplexPlugin, EventHandler, EventListener {
 		if (severity.equals("NOTICE") && msg.startsWith("Bootstrapped 100%")) {
 			connectionStatus.setBootstrapped();
 			backoff.reset();
-			if (isRunning()) callback.transportEnabled();
+			if (isRunning()) {
 				sendDevReports();
 				callback.transportEnabled();
 			}
 		}
 	}
--- a/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPluginFactory.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/plugin/tor/TorPluginFactory.java
@@ -12,6 +12,7 @@ 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.DuplexPluginFactory;
 import org.briarproject.bramble.api.reporting.DevReporter;
 import org.briarproject.bramble.api.system.LocationUtils;
 import org.briarproject.bramble.util.AndroidUtils;
@@ -39,18 +40,21 @@ public class TorPluginFactory implements DuplexPluginFactory {
 	private final ScheduledExecutorService scheduler;
 	private final Context appContext;
 	private final LocationUtils locationUtils;
 	private final DevReporter reporter;
 	private final EventBus eventBus;
 	private final SocketFactory torSocketFactory;
 	private final BackoffFactory backoffFactory;
 	public TorPluginFactory(Executor ioExecutor,
 			ScheduledExecutorService scheduler, Context appContext,
-			LocationUtils locationUtils, EventBus eventBus,
+			LocationUtils locationUtils, DevReporter reporter,
-			SocketFactory torSocketFactory, BackoffFactory backoffFactory) {
+			EventBus eventBus, SocketFactory torSocketFactory,
 			BackoffFactory backoffFactory) {
 		this.ioExecutor = ioExecutor;
 		this.scheduler = scheduler;
 		this.appContext = appContext;
 		this.locationUtils = locationUtils;
 		this.reporter = reporter;
 		this.eventBus = eventBus;
 		this.torSocketFactory = torSocketFactory;
 		this.backoffFactory = backoffFactory;
@@ -90,7 +94,7 @@ public class TorPluginFactory implements DuplexPluginFactory {
 		Backoff backoff = backoffFactory.createBackoff(MIN_POLLING_INTERVAL,
 				MAX_POLLING_INTERVAL, BACKOFF_BASE);
 		TorPlugin plugin = new TorPlugin(ioExecutor, scheduler, appContext,
-				locationUtils, torSocketFactory, backoff, callback,
+				locationUtils, reporter, torSocketFactory, backoff, callback,
 				architecture, MAX_LATENCY, MAX_IDLE_TIME);
 		eventBus.addListener(plugin);
 		return plugin;
--- a/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSecureRandomProvider.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/system/AndroidSecureRandomProvider.java
@@ -9,7 +9,6 @@ import android.net.wifi.WifiConfiguration;
 import android.net.wifi.WifiManager;
 import android.os.Build;
 import android.os.Parcel;
 import android.os.StrictMode;
 import android.provider.Settings;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
@@ -67,12 +66,9 @@ class AndroidSecureRandomProvider extends LinuxSecureRandomProvider {
 	@Override
 	protected void writeSeed() {
 		// Silence strict mode
 		StrictMode.ThreadPolicy tp = StrictMode.allowThreadDiskWrites();
 		super.writeSeed();
 		if (Build.VERSION.SDK_INT >= 16 && Build.VERSION.SDK_INT <= 18)
 			applyOpenSslFix();
 		StrictMode.setThreadPolicy(tp);
 	}
 	// Based on https://android-developers.googleblog.com/2013/08/some-securerandom-thoughts.html
--- a/bramble-android/src/main/java/org/briarproject/bramble/util/AndroidUtils.java
+++ b/bramble-android/src/main/java/org/briarproject/bramble/util/AndroidUtils.java
@@ -1,9 +1,7 @@
 package org.briarproject.bramble.util;
 import android.annotation.SuppressLint;
 import android.bluetooth.BluetoothAdapter;
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.os.Build;
 import android.provider.Settings;
@@ -12,15 +10,11 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 import java.util.logging.Logger;
 import static android.content.Context.MODE_PRIVATE;
 public class AndroidUtils {
 	private static final Logger LOG =
 			Logger.getLogger(AndroidUtils.class.getName());
 	// Fake Bluetooth address returned by BluetoothAdapter on API 23 and later
 	private static final String FAKE_BLUETOOTH_ADDRESS = "02:00:00:00:00:00";
@@ -41,7 +35,6 @@ public class AndroidUtils {
 	public static String getBluetoothAddress(Context ctx,
 			BluetoothAdapter adapter) {
 		// Return the adapter's address if it's valid and not fake
 		@SuppressLint("HardwareIds")
 		String address = adapter.getAddress();
 		if (isValidBluetoothAddress(address)) return address;
 		// Return the address from settings if it's valid and not fake
@@ -58,28 +51,17 @@ public class AndroidUtils {
 				&& !address.equals(FAKE_BLUETOOTH_ADDRESS);
 	}
-	public static void deleteAppData(Context ctx, SharedPreferences... clear) {
+	public static void deleteAppData(Context ctx) {
 		// Clear and commit shared preferences
 		for (SharedPreferences prefs : clear) {
 			if (!prefs.edit().clear().commit())
 				LOG.warning("Could not clear shared preferences");
 		}
 		// Delete files, except lib and shared_prefs directories
 		File dataDir = new File(ctx.getApplicationInfo().dataDir);
 		File[] children = dataDir.listFiles();
-		if (children == null) {
+		if (children != null) {
 			LOG.warning("Could not list files in app data dir");
 		} else {
 			for (File child : children) {
-				String name = child.getName();
+				if (!child.getName().equals("lib"))
 				if (!name.equals("lib") && !name.equals("shared_prefs")) {
 					IoUtils.deleteFileOrDir(child);
 				}
 			}
 		}
 		// Recreate the cache dir as some OpenGL drivers expect it to exist
-		if (!new File(dataDir, "cache").mkdir())
+		new File(dataDir, "cache").mkdir();
 			LOG.warning("Could not recreate cache dir");
 	}
 	public static File getReportDir(Context ctx) {
--- a/bramble-api/build.gradle
+++ b/bramble-api/build.gradle
@@ -2,7 +2,6 @@ apply plugin: 'java-library'
 sourceCompatibility = 1.8
 targetCompatibility = 1.8
 apply plugin: 'ru.vyarus.animalsniffer'
 apply plugin: 'witness'
 dependencies {
@@ -15,8 +14,6 @@ dependencies {
 	testImplementation "org.jmock:jmock-legacy:2.8.2"
 	testImplementation "org.hamcrest:hamcrest-library:1.3"
 	testImplementation "org.hamcrest:hamcrest-core:1.3"
 	signature 'org.codehaus.mojo.signature:java16:1.1@signature'
 }
 dependencyVerification {
@@ -29,9 +26,6 @@ dependencyVerification {
 			'org.apache.ant:ant-launcher:1.9.4:ant-launcher-1.9.4.jar:7bccea20b41801ca17bcbc909a78c835d0f443f12d639c77bd6ae3d05861608d',
 			'org.apache.ant:ant:1.9.4:ant-1.9.4.jar:649ae0730251de07b8913f49286d46bba7b92d47c5f332610aa426c4f02161d8',
 			'org.beanshell:bsh:1.3.0:bsh-1.3.0.jar:9b04edc75d19db54f1b4e8b5355e9364384c6cf71eb0a1b9724c159d779879f8',
 			'org.codehaus.mojo.signature:java16:1.1:java16-1.1.signature:53799223a2c98dba2d0add810bed76315460df285c69e4f397ae6098f87dd619',
 			'org.codehaus.mojo:animal-sniffer-ant-tasks:1.16:animal-sniffer-ant-tasks-1.16.jar:890040976fbe2d584619a6a61b1fd2e925b3b5eb342a85eb2762c467c0d64e90',
 			'org.codehaus.mojo:animal-sniffer:1.16:animal-sniffer-1.16.jar:72be8bcc226ba43b937c722a08a07852bfa1b11400089265d5df0ee7b38b1d52',
 			'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',
@@ -39,7 +33,6 @@ dependencyVerification {
 			'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-all:5.2:asm-all-5.2.jar:7fbffbc1db3422e2101689fd88df8384b15817b52b9b2b267b9f6d2511dc198d',
 			'org.ow2.asm:asm:5.0.4:asm-5.0.4.jar:896618ed8ae62702521a78bc7be42b7c491a08e6920a15f89a3ecdec31e9a220',
 	]
 }
@@ -55,3 +48,8 @@ task jarTest(type: Jar, dependsOn: testClasses) {
 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)
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/client/ContactGroupFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/client/ContactGroupFactory.java
@@ -12,19 +12,19 @@ public interface ContactGroupFactory {
 	/**
 	 * Creates a group that is not shared with any contacts.
 	 */
-	Group createLocalGroup(ClientId clientId, int majorVersion);
+	Group createLocalGroup(ClientId clientId, int clientVersion);
 	/**
 	 * Creates a group for the given client to share with the given contact.
 	 */
-	Group createContactGroup(ClientId clientId, int majorVersion,
+	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, int majorVersion,
+	Group createContactGroup(ClientId clientId, int clientVersion,
 			AuthorId authorId1, AuthorId authorId2);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeTask.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactExchangeTask.java
@@ -13,9 +13,9 @@ import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 public interface ContactExchangeTask {
 	/**
-	 * The current version of the contact exchange protocol.
+	 * The current version of the contact exchange protocol
 	 */
-	byte PROTOCOL_VERSION = 1;
+	int PROTOCOL_VERSION = 0;
 	/**
 	 * Label for deriving Alice's header key from the master secret.
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/ContactManager.java
@@ -24,8 +24,6 @@ public interface ContactManager {
 	 * Stores a contact associated with the given local and remote pseudonyms,
 	 * derives and stores transport keys for each transport, and returns an ID
 	 * for the contact.
 	 *
 	 * @param alice true if the local party is Alice
 	 */
 	ContactId addContact(Transaction txn, Author remote, AuthorId local,
 			SecretKey master, long timestamp, boolean alice, boolean verified,
@@ -40,14 +38,11 @@ public interface ContactManager {
 	/**
 	 * Stores a contact associated with the given local and remote pseudonyms,
-	 * derives and stores transport keys for each transport, and returns an ID
+	 * and returns an ID for the contact.
 	 * for the contact.
 	 *
 	 * @param alice true if the local party is Alice
 	 */
-	ContactId addContact(Author remote, AuthorId local, SecretKey master,
+	ContactId addContact(Author remote, AuthorId local,
-			long timestamp, boolean alice, boolean verified, boolean active)
+			SecretKey master, long timestamp, boolean alice, boolean verified,
-			throws DbException;
+			boolean active) throws DbException;
 	/**
 	 * Returns the contact with the given ID.
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/contact/RecordTypes.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/contact/RecordTypes.java
@@ -1,9 +0,0 @@
 package org.briarproject.bramble.api.contact;
 /**
 * Record types for the contact exchange protocol.
 */
 public interface RecordTypes {
 	byte CONTACT_INFO = 0;
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/crypto/KeyPair.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/crypto/KeyPair.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import javax.annotation.concurrent.Immutable;
 /**
- * A key pair consisting of a {@link PublicKey} and a {@link PrivateKey}.
+ * A key pair consisting of a {@link PublicKey} and a {@link PrivateKey).
 */
@Immutable
@NotNullByDefault
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfDictionary.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfDictionary.java
@@ -24,9 +24,9 @@ public class BdfDictionary extends TreeMap<String, Object> {
 	 * );
 	 * </pre>
 	 */
-	public static BdfDictionary of(Entry<String, ?>... entries) {
+	public static BdfDictionary of(Entry<String, Object>... entries) {
 		BdfDictionary d = new BdfDictionary();
-		for (Entry<String, ?> e : entries) d.put(e.getKey(), e.getValue());
+		for (Entry<String, Object> e : entries) d.put(e.getKey(), e.getValue());
 		return d;
 	}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReader.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReader.java
@@ -8,7 +8,6 @@ import java.io.IOException;
 public interface BdfReader {
 	int DEFAULT_NESTED_LIMIT = 5;
 	int DEFAULT_MAX_BUFFER_SIZE = 64 * 1024;
 	boolean eof() throws IOException;
@@ -40,13 +39,13 @@ public interface BdfReader {
 	boolean hasString() throws IOException;
-	String readString() throws IOException;
+	String readString(int maxLength) throws IOException;
 	void skipString() throws IOException;
 	boolean hasRaw() throws IOException;
-	byte[] readRaw() throws IOException;
+	byte[] readRaw(int maxLength) throws IOException;
 	void skipRaw() throws IOException;
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReaderFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/data/BdfReaderFactory.java
@@ -9,6 +9,5 @@ public interface BdfReaderFactory {
 	BdfReader createReader(InputStream in);
-	BdfReader createReader(InputStream in, int nestedLimit,
+	BdfReader createReader(InputStream in, int nestedLimit);
 			int maxBufferSize);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/db/DatabaseComponent.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/db/DatabaseComponent.java
@@ -104,12 +104,18 @@ public interface DatabaseComponent {
 			throws DbException;
 	/**
-	 * Stores the given transport keys for the given contact and returns a
+	 * Stores the given transport keys, optionally binding them to the given
-	 * key set ID.
+	 * contact, and returns a key set ID.
 	 */
-	KeySetId addTransportKeys(Transaction txn, ContactId c,
+	KeySetId addTransportKeys(Transaction txn, @Nullable ContactId c,
 			TransportKeys k) throws DbException;
 	/**
 	 * Binds the given keys for the given transport to the given contact.
 	 */
 	void bindTransportKeys(Transaction txn, ContactId c, TransportId t,
 			KeySetId k) throws DbException;
 	/**
 	 * Returns true if the database contains the given contact for the given
 	 * local pseudonym.
@@ -130,8 +136,8 @@ public interface DatabaseComponent {
 	/**
 	 * Deletes the message with the given ID. Unlike
-	 * {@link #removeMessage(Transaction, MessageId)}, the message ID,
+	 * {@link #removeMessage(Transaction, MessageId)}, the message ID and any
-	 * dependencies, metadata, and any other associated state are not deleted.
+	 * other associated data are not deleted.
 	 */
 	void deleteMessage(Transaction txn, MessageId m) throws DbException;
@@ -235,8 +241,7 @@ public interface DatabaseComponent {
 	 * <p/>
 	 * Read-only.
 	 */
-	Collection<Group> getGroups(Transaction txn, ClientId c, int majorVersion)
+	Collection<Group> getGroups(Transaction txn, ClientId c) throws DbException;
 			throws DbException;
 	/**
 	 * Returns the given group's visibility to the given contact, or
@@ -261,14 +266,6 @@ public interface DatabaseComponent {
 	 */
 	Collection<LocalAuthor> getLocalAuthors(Transaction txn) throws DbException;
 	/**
 	 * Returns the IDs of all delivered messages in the given group.
 	 * <p/>
 	 * Read-only.
 	 */
 	Collection<MessageId> getMessageIds(Transaction txn, GroupId g)
 		throws DbException;
 	/**
 	 * Returns the IDs of any messages that need to be validated.
 	 * <p/>
@@ -313,9 +310,9 @@ public interface DatabaseComponent {
 			throws DbException;
 	/**
-	 * Returns the metadata for any delivered messages in the given group with
+	 * Returns the metadata for any messages in the given group with metadata
-	 * metadata that matches all entries in the given query. If the query is
+	 * that matches all entries in the given query. If the query is empty, the
-	 * empty, the metadata for all delivered messages is returned.
+	 * metadata for all messages is returned.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -331,8 +328,8 @@ public interface DatabaseComponent {
 			throws DbException;
 	/**
-	 * Returns the metadata for the given delivered or pending message.
+	 * Returns the metadata for the given delivered and pending message.
-	 * This is only meant to be used by the ValidationManager.
+	 * This is meant to be only used by the ValidationManager
 	 * <p/>
 	 * Read-only.
 	 */
@@ -340,8 +337,8 @@ public interface DatabaseComponent {
 			throws DbException;
 	/**
-	 * Returns the status of all delivered messages in the given group with
+	 * Returns the status of all messages in the given group with respect to
-	 * respect to the given contact.
+	 * the given contact.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -376,8 +373,8 @@ public interface DatabaseComponent {
 	State getMessageState(Transaction txn, MessageId m) throws DbException;
 	/**
-	 * Returns the status of the given delivered message with respect to the
+	 * Returns the status of the given message with respect to the given
-	 * given contact.
+	 * contact.
 	 * <p/>
 	 * Read-only.
 	 */
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/db/DatabaseConfig.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/db/DatabaseConfig.java
@@ -14,8 +14,6 @@ public interface DatabaseConfig {
 	File getDatabaseDirectory();
 	File getDatabaseKeyDirectory();
 	void setEncryptionKey(SecretKey key);
 	@Nullable
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/keyagreement/event/KeyAgreementStoppedListeningEvent.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/keyagreement/event/KeyAgreementStoppedListeningEvent.java
@@ -1,9 +0,0 @@
 package org.briarproject.bramble.api.keyagreement.event;
 import org.briarproject.bramble.api.event.Event;
 /**
 * An event that is broadcast when a BQP task stops listening.
 */
 public class KeyAgreementStoppedListeningEvent extends Event {
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/lifecycle/LifecycleManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/lifecycle/LifecycleManager.java
@@ -43,20 +43,17 @@ public interface LifecycleManager {
 	}
 	/**
-	 * Registers a {@link Service} to be started and stopped. This method
+	 * Registers a {@link Service} to be started and stopped.
 	 * should be called before {@link #startServices(String)}.
 	 */
 	void registerService(Service s);
 	/**
-	 * Registers a {@link Client} to be started. This method should be called
+	 * Registers a {@link Client} to be started.
 	 * before {@link #startServices(String)}.
 	 */
 	void registerClient(Client c);
 	/**
-	 * Registers an {@link ExecutorService} to be shut down. This method
+	 * Registers an {@link ExecutorService} to be shut down.
 	 * should be called before {@link #startServices(String)}.
 	 */
 	void registerForShutdown(ExecutorService e);
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/FileConstants.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/FileConstants.java
@@ -1,6 +0,0 @@
 package org.briarproject.bramble.api.plugin;
 public interface FileConstants {
 	String PROP_PATH = "path";
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/Plugin.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/Plugin.java
@@ -2,9 +2,8 @@ package org.briarproject.bramble.api.plugin;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.properties.TransportProperties;
-import java.util.Map;
+import java.util.Collection;
@NotNullByDefault
 public interface Plugin {
@@ -40,19 +39,21 @@ public interface Plugin {
 	boolean isRunning();
 	/**
-	 * Returns true if the plugin should be polled periodically to attempt to
+	 * Returns true if the plugin's {@link #poll(Collection)} method should be
-	 * establish connections.
+	 * called periodically to attempt to establish connections.
 	 */
 	boolean shouldPoll();
 	/**
-	 * Returns the desired interval in milliseconds between polling attempts.
+	 * Returns the desired interval in milliseconds between calls to the
 	 * plugin's {@link #poll(Collection)} method.
 	 */
 	int getPollingInterval();
 	/**
-	 * Attempts to establish connections to the given contacts, passing any
+	 * Attempts to establish connections to contacts, passing any created
-	 * created connections to the callback.
+	 * connections to the callback. To avoid creating redundant connections,
 	 * the plugin may exclude the given contacts from polling.
 	 */
-	void poll(Map<ContactId, TransportProperties> contacts);
+	void poll(Collection<ContactId> connected);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/PluginCallback.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/PluginCallback.java
@@ -1,9 +1,12 @@
 package org.briarproject.bramble.api.plugin;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.settings.Settings;
 import java.util.Map;
 /**
 * An interface through which a transport plugin interacts with the rest of
 * the application.
@@ -22,7 +25,17 @@ public interface PluginCallback {
 	TransportProperties getLocalProperties();
 	/**
-	 * Merges the given settings with the plugin's settings
+	 * Returns the plugin's remote transport properties.
 	 */
 	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
 	 */
 	void mergeSettings(Settings s);
@@ -32,12 +45,34 @@ public interface PluginCallback {
 	void mergeLocalProperties(TransportProperties p);
 	/**
-	 * Signals that the transport is enabled.
+	 * Presents the user with a choice among two or more named options and
 	 * returns the user's response. The message may consist of a translatable
 	 * format string and arguments.
 	 *
 	 * @return an index into the array of options indicating the user's choice,
 	 * or -1 if the user cancelled the choice.
 	 */
 	int showChoice(String[] options, String... message);
 	/**
 	 * Asks the user to confirm an action and returns the user's response. The
 	 * message may consist of a translatable format string and arguments.
 	 */
 	boolean showConfirmationMessage(String... message);
 	/**
 	 * Shows a message to the user. The message may consist of a translatable
 	 * format string and arguments.
 	 */
 	void showMessage(String... message);
 	/**
 	 * Signal that the transport got enabled.
 	 */
 	void transportEnabled();
 	/**
-	 * Signals that the transport is disabled.
+	 * Signal that the transport got disabled.
 	 */
 	void transportDisabled();
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/PluginConfig.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/PluginConfig.java
@@ -12,6 +12,4 @@ public interface PluginConfig {
 	Collection<DuplexPluginFactory> getDuplexFactories();
 	Collection<SimplexPluginFactory> getSimplexFactories();
 	boolean shouldPoll();
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/TransportConnectionWriter.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/TransportConnectionWriter.java
@@ -22,6 +22,11 @@ public interface TransportConnectionWriter {
 	 */
 	int getMaxIdleTime();
 	/**
 	 * Returns the capacity of the transport connection in bytes.
 	 */
 	long getCapacity();
 	/**
 	 * Returns an output stream for writing to the transport connection.
 	 */
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/AbstractDuplexTransportConnection.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/AbstractDuplexTransportConnection.java
@@ -71,6 +71,11 @@ public abstract class AbstractDuplexTransportConnection
 			return plugin.getMaxIdleTime();
 		}
 		@Override
 		public long getCapacity() {
 			return Long.MAX_VALUE;
 		}
 		@Override
 		public OutputStream getOutputStream() throws IOException {
 			return AbstractDuplexTransportConnection.this.getOutputStream();
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/DuplexPlugin.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/DuplexPlugin.java
@@ -1,10 +1,10 @@
 package org.briarproject.bramble.api.plugin.duplex;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.keyagreement.KeyAgreementListener;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import javax.annotation.Nullable;
@@ -15,11 +15,12 @@ import javax.annotation.Nullable;
 public interface DuplexPlugin extends Plugin {
 	/**
-	 * Attempts to create and return a connection using the given transport
+	 * Attempts to create and return a connection to the given contact using
-	 * properties. Returns null if a connection cannot be created.
+	 * the current transport and configuration properties. Returns null if a
 	 * connection cannot be created.
 	 */
 	@Nullable
-	DuplexTransportConnection createConnection(TransportProperties p);
+	DuplexTransportConnection createConnection(ContactId c);
 	/**
 	 * Returns true if the plugin supports short-range key agreement.
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/DuplexPluginCallback.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/duplex/DuplexPluginCallback.java
@@ -5,8 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.PluginCallback;
 /**
- * An interface through which a duplex plugin interacts with the rest of the
+ * An interface for handling connections created by a duplex transport plugin.
 * application.
 */
@NotNullByDefault
 public interface DuplexPluginCallback extends PluginCallback {
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/simplex/SimplexPlugin.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/simplex/SimplexPlugin.java
@@ -1,10 +1,10 @@
 package org.briarproject.bramble.api.plugin.simplex;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import javax.annotation.Nullable;
@@ -15,16 +15,18 @@ import javax.annotation.Nullable;
 public interface SimplexPlugin extends Plugin {
 	/**
-	 * Attempts to create and return a reader for the given transport
+	 * Attempts to create and return a reader for the given contact using the
-	 * properties. Returns null if a reader cannot be created.
+	 * current transport and configuration properties. Returns null if a reader
 	 * cannot be created.
 	 */
 	@Nullable
-	TransportConnectionReader createReader(TransportProperties p);
+	TransportConnectionReader createReader(ContactId c);
 	/**
-	 * Attempts to create and return a writer for the given transport
+	 * Attempts to create and return a writer for the given contact using the
-	 * properties. Returns null if a writer cannot be created.
+	 * current transport and configuration properties. Returns null if a writer
 	 * cannot be created.
 	 */
 	@Nullable
-	TransportConnectionWriter createWriter(TransportProperties p);
+	TransportConnectionWriter createWriter(ContactId c);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/simplex/SimplexPluginCallback.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/plugin/simplex/SimplexPluginCallback.java
@@ -7,8 +7,8 @@ import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 /**
- * An interface through which a simplex plugin interacts with the rest of the
+ * An interface for handling readers and writers created by a simplex transport
- * application.
+ * plugin.
 */
@NotNullByDefault
 public interface SimplexPluginCallback extends PluginCallback {
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/properties/TransportPropertyManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/properties/TransportPropertyManager.java
@@ -15,17 +15,12 @@ public interface TransportPropertyManager {
 	/**
 	 * The unique ID of the transport property client.
 	 */
-	ClientId CLIENT_ID = new ClientId("org.briarproject.bramble.properties");
+	ClientId CLIENT_ID = new ClientId("org.briarproject.briar.properties");
 	/**
-	 * The current major version of the transport property client.
+	 * The current version of the transport property client.
 	 */
-	int MAJOR_VERSION = 0;
+	int CLIENT_VERSION = 0;
 	/**
 	 * The current minor version of the transport property client.
 	 */
 	int MINOR_VERSION = 0;
 	/**
 	 * Stores the given properties received while adding a contact - they will
@@ -42,8 +37,8 @@ public interface TransportPropertyManager {
 	/**
 	 * Returns the local transport properties for all transports.
-	 * <p/>
+	 * <br/>
-	 * Read-only.
+	 * TODO: Transaction can be read-only when code is simplified
 	 */
 	Map<TransportId, TransportProperties> getLocalProperties(Transaction txn)
 			throws DbException;
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/record/Record.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/record/Record.java
@@ -1,36 +0,0 @@
 package org.briarproject.bramble.api.record;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import javax.annotation.concurrent.Immutable;
@Immutable
@NotNullByDefault
 public class Record {
 	public static final int RECORD_HEADER_BYTES = 4;
 	public static final int MAX_RECORD_PAYLOAD_BYTES = 48 * 1024; // 48 KiB
 	private final byte protocolVersion, recordType;
 	private final byte[] payload;
 	public Record(byte protocolVersion, byte recordType, byte[] payload) {
 		if (payload.length > MAX_RECORD_PAYLOAD_BYTES)
 			throw new IllegalArgumentException();
 		this.protocolVersion = protocolVersion;
 		this.recordType = recordType;
 		this.payload = payload;
 	}
 	public byte getProtocolVersion() {
 		return protocolVersion;
 	}
 	public byte getRecordType() {
 		return recordType;
 	}
 	public byte[] getPayload() {
 		return payload;
 	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordReader.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordReader.java
@@ -1,20 +0,0 @@
 package org.briarproject.bramble.api.record;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.EOFException;
 import java.io.IOException;
@NotNullByDefault
 public interface RecordReader {
 	/**
 	 * Reads and returns the next record.
 	 *
 	 * @throws EOFException if the end of the stream is reached without reading
 	 * a complete record
 	 */
 	Record readRecord() throws IOException;
 	void close() throws IOException;
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordReaderFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordReaderFactory.java
@@ -1,8 +0,0 @@
 package org.briarproject.bramble.api.record;
 import java.io.InputStream;
 public interface RecordReaderFactory {
 	RecordReader createRecordReader(InputStream in);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordWriter.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordWriter.java
@@ -1,15 +0,0 @@
 package org.briarproject.bramble.api.record;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.IOException;
@NotNullByDefault
 public interface RecordWriter {
 	void writeRecord(Record r) throws IOException;
 	void flush() throws IOException;
 	void close() throws IOException;
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordWriterFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/record/RecordWriterFactory.java
@@ -1,8 +0,0 @@
 package org.briarproject.bramble.api.record;
 import java.io.OutputStream;
 public interface RecordWriterFactory {
 	RecordWriter createRecordWriter(OutputStream out);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/reporting/DevConfig.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/reporting/DevConfig.java
@@ -3,14 +3,10 @@ package org.briarproject.bramble.api.reporting;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.File;
@NotNullByDefault
 public interface DevConfig {
 	PublicKey getDevPublicKey();
 	String getDevOnionAddress();
 	File getReportDir();
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/reporting/DevReporter.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/reporting/DevReporter.java
@@ -23,6 +23,8 @@ public interface DevReporter {
 	/**
 	 * Sends any reports previously stored on disk.
 	 *
 	 * @param reportDir the directory where reports are stored.
 	 */
-	void sendReports();
+	void sendReports(File reportDir);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/Group.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/Group.java
@@ -5,24 +5,9 @@ import static org.briarproject.bramble.api.sync.SyncConstants.MAX_GROUP_DESCRIPT
 public class Group {
 	public enum Visibility {
-
+		INVISIBLE, // The group is not visible
-		INVISIBLE(0), // The group is not visible
+		VISIBLE, // The group is visible but messages are not shared
-		VISIBLE(1), // The group is visible, messages are accepted but not sent
+		SHARED // The group is visible and messages are shared
 		SHARED(2); // The group is visible, messages are accepted and sent
 		private final int value;
 		Visibility(int value) {
 			this.value = value;
 		}
 		public int getValue() {
 			return value;
 		}
 		public static Visibility min(Visibility a, Visibility b) {
 			return a.getValue() < b.getValue() ? a : b;
 		}
 	}
 	/**
@@ -32,16 +17,13 @@ public class Group {
 	private final GroupId id;
 	private final ClientId clientId;
 	private final int majorVersion;
 	private final byte[] descriptor;
-	public Group(GroupId id, ClientId clientId, int majorVersion,
+	public Group(GroupId id, ClientId clientId, byte[] descriptor) {
 			byte[] descriptor) {
 		if (descriptor.length > MAX_GROUP_DESCRIPTOR_LENGTH)
 			throw new IllegalArgumentException();
 		this.id = id;
 		this.clientId = clientId;
 		this.majorVersion = majorVersion;
 		this.descriptor = descriptor;
 	}
@@ -59,13 +41,6 @@ public class Group {
 		return clientId;
 	}
 	/**
 	 * Returns the major version of the client to which the group belongs.
 	 */
 	public int getMajorVersion() {
 		return majorVersion;
 	}
 	/**
 	 * Returns the group's descriptor.
 	 */
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/GroupFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/GroupFactory.java
@@ -6,7 +6,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 public interface GroupFactory {
 	/**
-	 * Creates a group with the given client ID, major version and descriptor.
+	 * Creates a group with the given client ID, client version and descriptor.
 	 */
-	Group createGroup(ClientId c, int majorVersion, byte[] descriptor);
+	Group createGroup(ClientId c, int clientVersion, byte[] descriptor);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/MessageFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/MessageFactory.java
@@ -7,7 +7,5 @@ public interface MessageFactory {
 	Message createMessage(GroupId g, long timestamp, byte[] body);
 	Message createMessage(byte[] raw);
 	Message createMessage(MessageId m, byte[] raw);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordReader.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordReader.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.IOException;
@NotNullByDefault
-public interface SyncRecordReader {
+public interface RecordReader {
 	boolean eof() throws IOException;
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordReaderFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordReaderFactory.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.InputStream;
@NotNullByDefault
-public interface SyncRecordReaderFactory {
+public interface RecordReaderFactory {
-	SyncRecordReader createRecordReader(InputStream in);
+	RecordReader createRecordReader(InputStream in);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordWriter.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordWriter.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.IOException;
@NotNullByDefault
-public interface SyncRecordWriter {
+public interface RecordWriter {
 	void writeAck(Ack a) throws IOException;
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordWriterFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncRecordWriterFactory.java
@@ -5,7 +5,7 @@ import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import java.io.OutputStream;
@NotNullByDefault
-public interface SyncRecordWriterFactory {
+public interface RecordWriterFactory {
-	SyncRecordWriter createRecordWriter(OutputStream out);
+	RecordWriter createRecordWriter(OutputStream out);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncConstants.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncConstants.java
@@ -2,8 +2,6 @@ package org.briarproject.bramble.api.sync;
 import org.briarproject.bramble.api.UniqueId;
 import static org.briarproject.bramble.api.record.Record.MAX_RECORD_PAYLOAD_BYTES;
 public interface SyncConstants {
 	/**
@@ -12,8 +10,16 @@ public interface SyncConstants {
 	byte PROTOCOL_VERSION = 0;
 	/**
-	 * The maximum length of a group descriptor in bytes.
+	 * The length of the record header in bytes.
 	 */
 	int RECORD_HEADER_LENGTH = 4;
 	/**
 	 * The maximum length of the record payload in bytes.
 	 */
 	int MAX_RECORD_PAYLOAD_LENGTH = 48 * 1024; // 48 KiB
 	/** The maximum length of a group descriptor in bytes. */
 	int MAX_GROUP_DESCRIPTOR_LENGTH = 16 * 1024; // 16 KiB
 	/**
@@ -34,5 +40,5 @@ public interface SyncConstants {
 	/**
 	 * The maximum number of message IDs in an ack, offer or request record.
 	 */
-	int MAX_MESSAGE_IDS = MAX_RECORD_PAYLOAD_BYTES / UniqueId.LENGTH;
+	int MAX_MESSAGE_IDS = MAX_RECORD_PAYLOAD_LENGTH / UniqueId.LENGTH;
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncSessionFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/SyncSessionFactory.java
@@ -2,9 +2,9 @@ package org.briarproject.bramble.api.sync;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import java.io.InputStream;
 import java.io.OutputStream;
@NotNullByDefault
 public interface SyncSessionFactory {
@@ -12,8 +12,8 @@ public interface SyncSessionFactory {
 	SyncSession createIncomingSession(ContactId c, InputStream in);
 	SyncSession createSimplexOutgoingSession(ContactId c, int maxLatency,
-			StreamWriter streamWriter);
+			OutputStream out);
 	SyncSession createDuplexOutgoingSession(ContactId c, int maxLatency,
-			int maxIdleTime, StreamWriter streamWriter);
+			int maxIdleTime, OutputStream out);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/sync/ValidationManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/sync/ValidationManager.java
@@ -3,7 +3,6 @@ package org.briarproject.bramble.api.sync;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Metadata;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 /**
@@ -34,20 +33,15 @@ public interface ValidationManager {
 	}
 	/**
-	 * Registers the message validator for the given client. This method
+	 * Sets the message validator for the given client.
 	 * should be called before {@link LifecycleManager#startServices(String)}.
 	 */
-	void registerMessageValidator(ClientId c, int majorVersion,
+	void registerMessageValidator(ClientId c, MessageValidator v);
 			MessageValidator v);
 	/**
-	 * Registers the incoming message hook for the given client. The hook will
+	 * Sets the incoming message hook for the given client. The hook will be
-	 * be called once for each incoming message that passes validation. This
+	 * called once for each incoming message that passes validation.
 	 * method should be called before
 	 * {@link LifecycleManager#startServices(String)}.
 	 */
-	void registerIncomingMessageHook(ClientId c, int majorVersion,
+	void registerIncomingMessageHook(ClientId c, IncomingMessageHook hook);
 			IncomingMessageHook hook);
 	interface MessageValidator {
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/system/Clock.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/system/Clock.java
@@ -7,12 +7,12 @@ package org.briarproject.bramble.api.system;
 public interface Clock {
 	/**
-	 * @see System#currentTimeMillis()
+	 * @see {@link System#currentTimeMillis()}
 	 */
 	long currentTimeMillis();
 	/**
-	 * @see Thread#sleep(long)
+	 * @see {@link Thread#sleep(long)}
 	 */
 	void sleep(long milliseconds) throws InterruptedException;
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/transport/KeyManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/transport/KeyManager.java
@@ -19,24 +19,44 @@ public interface KeyManager {
 	/**
 	 * Informs the key manager that a new contact has been added. Derives and
 	 * stores a set of transport keys for communicating with the contact over
-	 * each transport and returns the key set IDs.
+	 * each transport.
 	 * <p/>
 	 * {@link StreamContext StreamContexts} for the contact can be created
 	 * after this method has returned.
 	 *
 	 * @param alice true if the local party is Alice
 	 * @param active whether the derived keys can be used for outgoing streams
 	 */
-	Map<TransportId, KeySetId> addContact(Transaction txn, ContactId c,
+	void addContact(Transaction txn, ContactId c, SecretKey master,
-			SecretKey master, long timestamp, boolean alice, boolean active)
+			long timestamp, boolean alice) throws DbException;
 	/**
 	 * Derives and stores a set of unbound transport keys for each transport
 	 * and returns the key set IDs.
 	 * <p/>
 	 * The keys must be bound before they can be used for incoming streams,
 	 * and also activated before they can be used for outgoing streams.
 	 */
 	Map<TransportId, KeySetId> addUnboundKeys(Transaction txn, SecretKey master,
 			long timestamp, boolean alice) throws DbException;
 	/**
 	 * Binds the given transport keys to the given contact.
 	 */
 	void bindKeys(Transaction txn, ContactId c, Map<TransportId, KeySetId> keys)
 			throws DbException;
 	/**
-	 * Marks the given transport keys as usable for outgoing streams.
+	 * Marks the given transport keys as usable for outgoing streams. Keys must
 	 * be bound before they are activated.
 	 */
 	void activateKeys(Transaction txn, Map<TransportId, KeySetId> keys)
 			throws DbException;
 	/**
 	 * Removes the given transport keys, which must not have been bound, from
 	 * the manager and the database.
 	 */
 	void removeKeys(Transaction txn, Map<TransportId, KeySetId> keys)
 		throws DbException;
 	/**
 	 * Returns true if we have keys that can be used for outgoing streams to
 	 * the given contact over the given transport.
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/transport/KeySet.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/transport/KeySet.java
@@ -3,20 +3,23 @@ package org.briarproject.bramble.api.transport;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 /**
- * A set of transport keys for communicating with a contact.
+ * A set of transport keys for communicating with a contact. If the keys have
 * not yet been bound to a contact, {@link #getContactId()}} returns null.
 */
@Immutable
@NotNullByDefault
 public class KeySet {
 	private final KeySetId keySetId;
 	@Nullable
 	private final ContactId contactId;
 	private final TransportKeys transportKeys;
-	public KeySet(KeySetId keySetId, ContactId contactId,
+	public KeySet(KeySetId keySetId, @Nullable ContactId contactId,
 			TransportKeys transportKeys) {
 		this.keySetId = keySetId;
 		this.contactId = contactId;
@@ -27,6 +30,7 @@ public class KeySet {
 		return keySetId;
 	}
 	@Nullable
 	public ContactId getContactId() {
 		return contactId;
 	}
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/transport/StreamWriter.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/transport/StreamWriter.java
@@ -1,19 +0,0 @@
 package org.briarproject.bramble.api.transport;
 import java.io.IOException;
 import java.io.OutputStream;
 /**
 * An interface for writing data to a transport connection. Data will be
 * encrypted and authenticated before being written to the connection.
 */
 public interface StreamWriter {
 	OutputStream getOutputStream();
 	/**
 	 * Sends the end of stream marker, informing the recipient that no more
 	 * data will be sent. The connection is flushed but not closed.
 	 */
 	void sendEndOfStream() throws IOException;
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/transport/StreamWriterFactory.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/transport/StreamWriterFactory.java
@@ -12,12 +12,12 @@ public interface StreamWriterFactory {
 	 * Creates an {@link OutputStream OutputStream} for writing to a
 	 * transport stream
 	 */
-	StreamWriter createStreamWriter(OutputStream out, StreamContext ctx);
+	OutputStream createStreamWriter(OutputStream out, StreamContext ctx);
 	/**
 	 * Creates an {@link OutputStream OutputStream} for writing to a contact
 	 * exchange stream.
 	 */
-	StreamWriter createContactExchangeStreamWriter(OutputStream out,
+	OutputStream createContactExchangeStreamWriter(OutputStream out,
 			SecretKey headerKey);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/ui/UiCallback.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/ui/UiCallback.java
@@ -0,0 +1,26 @@
 package org.briarproject.bramble.api.ui;
 public interface UiCallback {
 	/**
 	 * Presents the user with a choice among two or more named options and
 	 * returns the user's response. The message may consist of a translatable
 	 * format string and arguments.
 	 *
 	 * @return an index into the array of options indicating the user's choice,
 	 * or -1 if the user cancelled the choice.
 	 */
 	int showChoice(String[] options, String... message);
 	/**
 	 * Asks the user to confirm an action and returns the user's response. The
 	 * message may consist of a translatable format string and arguments.
 	 */
 	boolean showConfirmationMessage(String... message);
 	/**
 	 * Shows a message to the user. The message may consist of a translatable
 	 * format string and arguments.
 	 */
 	void showMessage(String... message);
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/versioning/ClientMajorVersion.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/versioning/ClientMajorVersion.java
@@ -1,50 +0,0 @@
 package org.briarproject.bramble.api.versioning;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.ClientId;
 import javax.annotation.concurrent.Immutable;
@Immutable
@NotNullByDefault
 public class ClientMajorVersion implements Comparable<ClientMajorVersion> {
 	private final ClientId clientId;
 	private final int majorVersion;
 	public ClientMajorVersion(ClientId clientId, int majorVersion) {
 		this.clientId = clientId;
 		this.majorVersion = majorVersion;
 	}
 	public ClientId getClientId() {
 		return clientId;
 	}
 	public int getMajorVersion() {
 		return majorVersion;
 	}
 	@Override
 	public boolean equals(Object o) {
 		if (o instanceof ClientMajorVersion) {
 			ClientMajorVersion cv = (ClientMajorVersion) o;
 			return clientId.equals(cv.clientId)
 					&& majorVersion == cv.majorVersion;
 		}
 		return false;
 	}
 	@Override
 	public int hashCode() {
 		return (clientId.hashCode() << 16) + majorVersion;
 	}
 	@Override
 	public int compareTo(ClientMajorVersion cv) {
 		int compare = clientId.compareTo(cv.clientId);
 		if (compare != 0) return compare;
 		return majorVersion - cv.majorVersion;
 	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/api/versioning/ClientVersioningManager.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/api/versioning/ClientVersioningManager.java
@@ -1,45 +0,0 @@
 package org.briarproject.bramble.api.versioning;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.ClientId;
 import org.briarproject.bramble.api.sync.Group.Visibility;
@NotNullByDefault
 public interface ClientVersioningManager {
 	/**
 	 * The unique ID of the versioning client.
 	 */
 	ClientId CLIENT_ID = new ClientId("org.briarproject.bramble.versioning");
 	/**
 	 * The current major version of the versioning client.
 	 */
 	int MAJOR_VERSION = 0;
 	/**
 	 * Registers a client that will be advertised to contacts. The hook will
 	 * be called when the visibility of the client changes. This method should
 	 * be called before {@link LifecycleManager#startServices(String)}.
 	 */
 	void registerClient(ClientId clientId, int majorVersion, int minorVersion,
 			ClientVersioningHook hook);
 	/**
 	 * Returns the visibility of the given client with respect to the given
 	 * contact.
 	 */
 	Visibility getClientVisibility(Transaction txn, ContactId contactId,
 			ClientId clientId, int majorVersion) throws DbException;
 	interface ClientVersioningHook {
 		void onClientVisibilityChanging(Transaction txn, Contact c,
 				Visibility v) throws DbException;
 	}
 }
--- a/bramble-api/src/main/java/org/briarproject/bramble/util/IoUtils.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/util/IoUtils.java
@@ -9,40 +9,25 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.net.Socket;
 import java.util.logging.Logger;
 import javax.annotation.Nullable;
 import static java.util.logging.Level.WARNING;
@NotNullByDefault
 public class IoUtils {
 	private static final Logger LOG = Logger.getLogger(IoUtils.class.getName());
 	public static void deleteFileOrDir(File f) {
 		if (f.isFile()) {
-			delete(f);
+			f.delete();
 		} else if (f.isDirectory()) {
 			File[] children = f.listFiles();
-			if (children == null) {
+			if (children != null)
 				if (LOG.isLoggable(WARNING)) {
 					LOG.warning("Could not list files in "
 							+ f.getAbsolutePath());
 				}
 			} else {
 				for (File child : children) deleteFileOrDir(child);
-			}
+			f.delete();
 			delete(f);
 		}
 	}
-	private static void delete(File f) {
+	public static void copyAndClose(InputStream in, OutputStream out)
-		if (!f.delete() && LOG.isLoggable(WARNING))
+			throws IOException {
 			LOG.warning("Could not delete " + f.getAbsolutePath());
 	}
 	public static void copyAndClose(InputStream in, OutputStream out) {
 		byte[] buf = new byte[4096];
 		try {
 			while (true) {
--- a/bramble-api/src/main/java/org/briarproject/bramble/util/OsUtils.java
+++ b/bramble-api/src/main/java/org/briarproject/bramble/util/OsUtils.java
@@ -22,6 +22,19 @@ public class OsUtils {
 		return os != null && os.contains("Mac OS");
 	}
 	public static boolean isMacLeopardOrNewer() {
 		if (!isMac() || version == null) return false;
 		try {
 			String[] v = version.split("\\.");
 			if (v.length != 3) return false;
 			int major = Integer.parseInt(v[0]);
 			int minor = Integer.parseInt(v[1]);
 			return major >= 10 && minor >= 5;
 		} catch (NumberFormatException e) {
 			return false;
 		}
 	}
 	public static boolean isLinux() {
 		return os != null && os.contains("Linux") && !isAndroid();
 	}
--- a/bramble-api/src/test/java/org/briarproject/bramble/test/TestUtils.java
+++ b/bramble-api/src/test/java/org/briarproject/bramble/test/TestUtils.java
@@ -117,16 +117,15 @@ public class TestUtils {
 		return new Author(id, FORMAT_VERSION, name, publicKey);
 	}
-	public static Group getGroup(ClientId clientId, int majorVersion) {
+	public static Group getGroup(ClientId clientId) {
 		int descriptorLength = 1 + random.nextInt(MAX_GROUP_DESCRIPTOR_LENGTH);
-		return getGroup(clientId, majorVersion, descriptorLength);
+		return getGroup(clientId, descriptorLength);
 	}
-	public static Group getGroup(ClientId clientId, int majorVersion,
+	public static Group getGroup(ClientId clientId, int descriptorLength) {
 			int descriptorLength) {
 		GroupId groupId = new GroupId(getRandomId());
 		byte[] descriptor = getRandomBytes(descriptorLength);
-		return new Group(groupId, clientId, majorVersion, descriptor);
+		return new Group(groupId, clientId, descriptor);
 	}
 	public static Message getMessage(GroupId groupId) {
--- a/bramble-core/build.gradle
+++ b/bramble-core/build.gradle
@@ -2,7 +2,6 @@ apply plugin: 'java-library'
 sourceCompatibility = 1.8
 targetCompatibility = 1.8
 apply plugin: 'ru.vyarus.animalsniffer'
 apply plugin: 'net.ltgt.apt'
 apply plugin: 'idea'
 apply plugin: 'witness'
@@ -27,13 +26,12 @@ dependencies {
 	testImplementation "org.hamcrest:hamcrest-core:1.3"
 	testApt 'com.google.dagger:dagger-compiler:2.0.2'
 	signature 'org.codehaus.mojo.signature:java16:1.1@signature'
 }
 dependencyVerification {
 	verify = [
 			'cglib:cglib:3.2.0:cglib-3.2.0.jar:adb13bab79712ad6bdf1bd59f2a3918018a8016e722e8a357065afb9e6690861',
 			'com.google.code.findbugs:jsr305:3.0.2:jsr305-3.0.2.jar:766ad2a0783f2687962c8ad74ceecc38a28b9f72a2d085ee438b7813e928d0c7',
 			'com.google.dagger:dagger-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',
@@ -47,9 +45,6 @@ dependencyVerification {
 			'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.codehaus.mojo.signature:java16:1.1:java16-1.1.signature:53799223a2c98dba2d0add810bed76315460df285c69e4f397ae6098f87dd619',
 			'org.codehaus.mojo:animal-sniffer-ant-tasks:1.16:animal-sniffer-ant-tasks-1.16.jar:890040976fbe2d584619a6a61b1fd2e925b3b5eb342a85eb2762c467c0d64e90',
 			'org.codehaus.mojo:animal-sniffer:1.16:animal-sniffer-1.16.jar:72be8bcc226ba43b937c722a08a07852bfa1b11400089265d5df0ee7b38b1d52',
 			'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',
@@ -58,7 +53,6 @@ dependencyVerification {
 			'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-all:5.2:asm-all-5.2.jar:7fbffbc1db3422e2101689fd88df8384b15817b52b9b2b267b9f6d2511dc198d',
 			'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',
 	]
@@ -75,3 +69,8 @@ task jarTest(type: Jar, dependsOn: testClasses) {
 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)
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/BrambleCoreEagerSingletons.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/BrambleCoreEagerSingletons.java
@@ -1,23 +1,21 @@
 package org.briarproject.bramble;
 import org.briarproject.bramble.contact.ContactModule;
-import org.briarproject.bramble.crypto.CryptoExecutorModule;
+import org.briarproject.bramble.crypto.CryptoModule;
 import org.briarproject.bramble.db.DatabaseExecutorModule;
 import org.briarproject.bramble.identity.IdentityModule;
 import org.briarproject.bramble.lifecycle.LifecycleModule;
 import org.briarproject.bramble.plugin.PluginModule;
 import org.briarproject.bramble.properties.PropertiesModule;
 import org.briarproject.bramble.reporting.ReportingModule;
 import org.briarproject.bramble.sync.SyncModule;
 import org.briarproject.bramble.system.SystemModule;
 import org.briarproject.bramble.transport.TransportModule;
 import org.briarproject.bramble.versioning.VersioningModule;
 public interface BrambleCoreEagerSingletons {
 	void inject(ContactModule.EagerSingletons init);
-	void inject(CryptoExecutorModule.EagerSingletons init);
+	void inject(CryptoModule.EagerSingletons init);
 	void inject(DatabaseExecutorModule.EagerSingletons init);
@@ -29,13 +27,9 @@ public interface BrambleCoreEagerSingletons {
 	void inject(PropertiesModule.EagerSingletons init);
 	void inject(ReportingModule.EagerSingletons init);
 	void inject(SyncModule.EagerSingletons init);
 	void inject(SystemModule.EagerSingletons init);
 	void inject(TransportModule.EagerSingletons init);
 	void inject(VersioningModule.EagerSingletons init);
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/BrambleCoreModule.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/BrambleCoreModule.java
@@ -2,7 +2,6 @@ package org.briarproject.bramble;
 import org.briarproject.bramble.client.ClientModule;
 import org.briarproject.bramble.contact.ContactModule;
 import org.briarproject.bramble.crypto.CryptoExecutorModule;
 import org.briarproject.bramble.crypto.CryptoModule;
 import org.briarproject.bramble.data.DataModule;
 import org.briarproject.bramble.db.DatabaseExecutorModule;
@@ -13,7 +12,6 @@ import org.briarproject.bramble.keyagreement.KeyAgreementModule;
 import org.briarproject.bramble.lifecycle.LifecycleModule;
 import org.briarproject.bramble.plugin.PluginModule;
 import org.briarproject.bramble.properties.PropertiesModule;
 import org.briarproject.bramble.record.RecordModule;
 import org.briarproject.bramble.reliability.ReliabilityModule;
 import org.briarproject.bramble.reporting.ReportingModule;
 import org.briarproject.bramble.settings.SettingsModule;
@@ -21,7 +19,6 @@ import org.briarproject.bramble.socks.SocksModule;
 import org.briarproject.bramble.sync.SyncModule;
 import org.briarproject.bramble.system.SystemModule;
 import org.briarproject.bramble.transport.TransportModule;
 import org.briarproject.bramble.versioning.VersioningModule;
 import dagger.Module;
@@ -29,7 +26,6 @@ import dagger.Module;
 		ClientModule.class,
 		ContactModule.class,
 		CryptoModule.class,
 		CryptoExecutorModule.class,
 		DataModule.class,
 		DatabaseModule.class,
 		DatabaseExecutorModule.class,
@@ -39,30 +35,26 @@ import dagger.Module;
 		LifecycleModule.class,
 		PluginModule.class,
 		PropertiesModule.class,
 		RecordModule.class,
 		ReliabilityModule.class,
 		ReportingModule.class,
 		SettingsModule.class,
 		SocksModule.class,
 		SyncModule.class,
 		SystemModule.class,
-		TransportModule.class,
+		TransportModule.class
 		VersioningModule.class
 })
 public class BrambleCoreModule {
 	public static void initEagerSingletons(BrambleCoreEagerSingletons c) {
 		c.inject(new ContactModule.EagerSingletons());
-		c.inject(new CryptoExecutorModule.EagerSingletons());
+		c.inject(new CryptoModule.EagerSingletons());
 		c.inject(new DatabaseExecutorModule.EagerSingletons());
 		c.inject(new IdentityModule.EagerSingletons());
 		c.inject(new LifecycleModule.EagerSingletons());
 		c.inject(new PluginModule.EagerSingletons());
 		c.inject(new PropertiesModule.EagerSingletons());
 		c.inject(new ReportingModule.EagerSingletons());
 		c.inject(new SyncModule.EagerSingletons());
 		c.inject(new SystemModule.EagerSingletons());
 		c.inject(new TransportModule.EagerSingletons());
 		c.inject(new VersioningModule.EagerSingletons());
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/client/ContactGroupFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/client/ContactGroupFactoryImpl.java
@@ -32,25 +32,25 @@ class ContactGroupFactoryImpl implements ContactGroupFactory {
 	}
 	@Override
-	public Group createLocalGroup(ClientId clientId, int majorVersion) {
+	public Group createLocalGroup(ClientId clientId, int clientVersion) {
-		return groupFactory.createGroup(clientId, majorVersion,
+		return groupFactory.createGroup(clientId, clientVersion,
 				LOCAL_GROUP_DESCRIPTOR);
 	}
 	@Override
-	public Group createContactGroup(ClientId clientId, int majorVersion,
+	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, majorVersion, descriptor);
+		return groupFactory.createGroup(clientId, clientVersion, descriptor);
 	}
 	@Override
-	public Group createContactGroup(ClientId clientId, int majorVersion,
+	public Group createContactGroup(ClientId clientId, int clientVersion,
 			AuthorId authorId1, AuthorId authorId2) {
 		byte[] descriptor = createGroupDescriptor(authorId1, authorId2);
-		return groupFactory.createGroup(clientId, majorVersion, descriptor);
+		return groupFactory.createGroup(clientId, clientVersion, descriptor);
 	}
 	private byte[] createGroupDescriptor(AuthorId local, AuthorId remote) {
--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeTaskImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactExchangeTaskImpl.java
@@ -1,20 +1,23 @@
 package org.briarproject.bramble.contact;
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.contact.ContactExchangeListener;
 import org.briarproject.bramble.api.contact.ContactExchangeTask;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.ContactManager;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.crypto.SecretKey;
 import org.briarproject.bramble.api.data.BdfDictionary;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.BdfReader;
 import org.briarproject.bramble.api.data.BdfReaderFactory;
 import org.briarproject.bramble.api.data.BdfWriter;
 import org.briarproject.bramble.api.data.BdfWriterFactory;
 import org.briarproject.bramble.api.db.ContactExistsException;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorFactory;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
@@ -23,31 +26,30 @@ import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.record.Record;
 import org.briarproject.bramble.api.record.RecordReader;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.security.GeneralSecurityException;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.logging.Logger;
 import javax.inject.Inject;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.api.contact.RecordTypes.CONTACT_INFO;
+import static org.briarproject.bramble.api.identity.Author.FORMAT_VERSION;
 import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
 import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_PUBLIC_KEY_LENGTH;
 import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_SIGNATURE_LENGTH;
-import static org.briarproject.bramble.util.ValidationUtils.checkLength;
+import static org.briarproject.bramble.api.plugin.TransportId.MAX_TRANSPORT_ID_LENGTH;
-import static org.briarproject.bramble.util.ValidationUtils.checkSize;
+import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MAX_PROPERTIES_PER_TRANSPORT;
 import static org.briarproject.bramble.api.properties.TransportPropertyConstants.MAX_PROPERTY_LENGTH;
@MethodsNotNullByDefault
@ParametersNotNullByDefault
@@ -60,9 +62,9 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 			"org.briarproject.briar.contact/EXCHANGE";
 	private final DatabaseComponent db;
-	private final ClientHelper clientHelper;
+	private final AuthorFactory authorFactory;
-	private final RecordReaderFactory recordReaderFactory;
+	private final BdfReaderFactory bdfReaderFactory;
-	private final RecordWriterFactory recordWriterFactory;
+	private final BdfWriterFactory bdfWriterFactory;
 	private final Clock clock;
 	private final ConnectionManager connectionManager;
 	private final ContactManager contactManager;
@@ -79,17 +81,17 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 	private volatile boolean alice;
 	@Inject
-	ContactExchangeTaskImpl(DatabaseComponent db, ClientHelper clientHelper,
+	ContactExchangeTaskImpl(DatabaseComponent db,
-			RecordReaderFactory recordReaderFactory,
+			AuthorFactory authorFactory, BdfReaderFactory bdfReaderFactory,
-			RecordWriterFactory recordWriterFactory, Clock clock,
+			BdfWriterFactory bdfWriterFactory, Clock clock,
 			ConnectionManager connectionManager, ContactManager contactManager,
 			TransportPropertyManager transportPropertyManager,
 			CryptoComponent crypto, StreamReaderFactory streamReaderFactory,
 			StreamWriterFactory streamWriterFactory) {
 		this.db = db;
-		this.clientHelper = clientHelper;
+		this.authorFactory = authorFactory;
-		this.recordReaderFactory = recordReaderFactory;
+		this.bdfReaderFactory = bdfReaderFactory;
-		this.recordWriterFactory = recordWriterFactory;
+		this.bdfWriterFactory = bdfWriterFactory;
 		this.clock = clock;
 		this.connectionManager = connectionManager;
 		this.contactManager = contactManager;
@@ -124,18 +126,18 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			listener.contactExchangeFailed();
-			tryToClose(conn);
+			tryToClose(conn, true);
 			return;
 		}
 		// Get the local transport properties
-		Map<TransportId, TransportProperties> localProperties;
+		Map<TransportId, TransportProperties> localProperties, remoteProperties;
 		try {
 			localProperties = transportPropertyManager.getLocalProperties();
 		} catch (DbException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			listener.contactExchangeFailed();
-			tryToClose(conn);
+			tryToClose(conn, true);
 			return;
 		}
@@ -149,138 +151,159 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		InputStream streamReader =
 				streamReaderFactory.createContactExchangeStreamReader(in,
 						alice ? bobHeaderKey : aliceHeaderKey);
-		RecordReader recordReader =
+		BdfReader r = bdfReaderFactory.createReader(streamReader);
 				recordReaderFactory.createRecordReader(streamReader);
 		// Create the writers
-		StreamWriter streamWriter =
+		OutputStream streamWriter =
 				streamWriterFactory.createContactExchangeStreamWriter(out,
 						alice ? aliceHeaderKey : bobHeaderKey);
-		RecordWriter recordWriter =
+		BdfWriter w = bdfWriterFactory.createWriter(streamWriter);
 				recordWriterFactory.createRecordWriter(streamWriter.getOutputStream());
 		// Derive the nonces to be signed
 		byte[] aliceNonce = crypto.mac(ALICE_NONCE_LABEL, masterSecret,
 				new byte[] {PROTOCOL_VERSION});
 		byte[] bobNonce = crypto.mac(BOB_NONCE_LABEL, masterSecret,
 				new byte[] {PROTOCOL_VERSION});
 		byte[] localNonce = alice ? aliceNonce : bobNonce;
 		byte[] remoteNonce = alice ? bobNonce : aliceNonce;
-		// Sign the nonce
+		// Exchange pseudonyms, signed nonces, and timestamps
 		byte[] localSignature = sign(localAuthor, localNonce);
 		// Exchange contact info
 		long localTimestamp = clock.currentTimeMillis();
-		ContactInfo remoteInfo;
+		Author remoteAuthor;
 		long remoteTimestamp;
 		try {
 			if (alice) {
-				sendContactInfo(recordWriter, localAuthor, localProperties,
+				sendPseudonym(w, aliceNonce);
-						localSignature, localTimestamp);
+				sendTimestamp(w, localTimestamp);
-				recordWriter.flush();
+				sendTransportProperties(w, localProperties);
-				remoteInfo = receiveContactInfo(recordReader);
+				w.flush();
 				remoteAuthor = receivePseudonym(r, bobNonce);
 				remoteTimestamp = receiveTimestamp(r);
 				remoteProperties = receiveTransportProperties(r);
 			} else {
-				remoteInfo = receiveContactInfo(recordReader);
+				remoteAuthor = receivePseudonym(r, aliceNonce);
-				sendContactInfo(recordWriter, localAuthor, localProperties,
+				remoteTimestamp = receiveTimestamp(r);
-						localSignature, localTimestamp);
+				remoteProperties = receiveTransportProperties(r);
-				recordWriter.flush();
+				sendPseudonym(w, bobNonce);
 				sendTimestamp(w, localTimestamp);
 				sendTransportProperties(w, localProperties);
 				w.flush();
 			}
-			// Send EOF on the outgoing stream
+			// Close the outgoing stream and expect EOF on the incoming stream
-			streamWriter.sendEndOfStream();
+			w.close();
-			// Skip any remaining records from the incoming stream
+			if (!r.eof()) LOG.warning("Unexpected data at end of connection");
-			try {
+		} catch (GeneralSecurityException | IOException e) {
 				while (true) recordReader.readRecord();
 			} catch (EOFException expected) {
 				LOG.info("End of stream");
 			}
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			listener.contactExchangeFailed();
-			tryToClose(conn);
+			tryToClose(conn, true);
 			return;
 		}
 		// Verify the contact's signature
 		if (!verify(remoteInfo.author, remoteNonce, remoteInfo.signature)) {
 			LOG.warning("Invalid signature");
 			listener.contactExchangeFailed();
 			tryToClose(conn);
 			return;
 		}
 		// The agreed timestamp is the minimum of the peers' timestamps
-		long timestamp = Math.min(localTimestamp, remoteInfo.timestamp);
+		long timestamp = Math.min(localTimestamp, remoteTimestamp);
 		try {
 			// Add the contact
-			ContactId contactId = addContact(remoteInfo.author, timestamp,
+			ContactId contactId = addContact(remoteAuthor, timestamp,
-					remoteInfo.properties);
+					remoteProperties);
 			// Reuse the connection as a transport connection
 			connectionManager.manageOutgoingConnection(contactId, transportId,
 					conn);
 			// Pseudonym exchange succeeded
 			LOG.info("Pseudonym exchange succeeded");
-			listener.contactExchangeSucceeded(remoteInfo.author);
+			listener.contactExchangeSucceeded(remoteAuthor);
 		} catch (ContactExistsException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			tryToClose(conn);
+			tryToClose(conn, true);
-			listener.duplicateContact(remoteInfo.author);
+			listener.duplicateContact(remoteAuthor);
 		} catch (DbException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
-			tryToClose(conn);
+			tryToClose(conn, true);
 			listener.contactExchangeFailed();
 		}
 	}
-	private byte[] sign(LocalAuthor author, byte[] nonce) {
+	private void sendPseudonym(BdfWriter w, byte[] nonce)
-		try {
+			throws GeneralSecurityException, IOException {
-			return crypto.sign(SIGNING_LABEL_EXCHANGE, nonce,
+		// Sign the nonce
-					author.getPrivateKey());
+		byte[] privateKey = localAuthor.getPrivateKey();
-		} catch (GeneralSecurityException e) {
+		byte[] sig = crypto.sign(SIGNING_LABEL_EXCHANGE, nonce, privateKey);
-			throw new AssertionError();
+
 		// Write the name, public key and signature
 		w.writeListStart();
 		w.writeLong(localAuthor.getFormatVersion());
 		w.writeString(localAuthor.getName());
 		w.writeRaw(localAuthor.getPublicKey());
 		w.writeRaw(sig);
 		w.writeListEnd();
 		LOG.info("Sent pseudonym");
 	}
 	private Author receivePseudonym(BdfReader r, byte[] nonce)
 			throws GeneralSecurityException, IOException {
 		// Read the format version, name, public key and signature
 		r.readListStart();
 		int formatVersion = (int) r.readLong();
 		if (formatVersion != FORMAT_VERSION) throw new FormatException();
 		String name = r.readString(MAX_AUTHOR_NAME_LENGTH);
 		if (name.isEmpty()) throw new FormatException();
 		byte[] publicKey = r.readRaw(MAX_PUBLIC_KEY_LENGTH);
 		if (publicKey.length == 0) throw new FormatException();
 		byte[] sig = r.readRaw(MAX_SIGNATURE_LENGTH);
 		if (sig.length == 0) throw new FormatException();
 		r.readListEnd();
 		LOG.info("Received pseudonym");
 		// Verify the signature
 		if (!crypto.verifySignature(sig, SIGNING_LABEL_EXCHANGE, nonce,
 				publicKey)) {
 			if (LOG.isLoggable(INFO))
 				LOG.info("Invalid signature");
 			throw new GeneralSecurityException();
 		}
 		return authorFactory.createAuthor(formatVersion, name, publicKey);
 	}
-	private boolean verify(Author author, byte[] nonce, byte[] signature) {
+	private void sendTimestamp(BdfWriter w, long timestamp)
 		try {
 			return crypto.verifySignature(signature, SIGNING_LABEL_EXCHANGE,
 					nonce, author.getPublicKey());
 		} catch (GeneralSecurityException e) {
 			return false;
 		}
 	}
 	private void sendContactInfo(RecordWriter recordWriter, Author author,
 			Map<TransportId, TransportProperties> properties, byte[] signature,
 			long timestamp) throws IOException {
 		BdfList authorList = clientHelper.toList(author);
 		BdfDictionary props = clientHelper.toDictionary(properties);
 		BdfList payload = BdfList.of(authorList, props, signature, timestamp);
 		recordWriter.writeRecord(new Record(PROTOCOL_VERSION, CONTACT_INFO,
 				clientHelper.toByteArray(payload)));
 		LOG.info("Sent contact info");
 	}
 	private ContactInfo receiveContactInfo(RecordReader recordReader)
 			throws IOException {
-		Record record;
+		w.writeLong(timestamp);
-		do {
+		LOG.info("Sent timestamp");
-			record = recordReader.readRecord();
+	}
-			if (record.getProtocolVersion() != PROTOCOL_VERSION)
+
-				throw new FormatException();
+	private long receiveTimestamp(BdfReader r) throws IOException {
-		} while (record.getRecordType() != CONTACT_INFO);
+		long timestamp = r.readLong();
 		LOG.info("Received contact info");
 		BdfList payload = clientHelper.toList(record.getPayload());
 		checkSize(payload, 4);
 		Author author = clientHelper.parseAndValidateAuthor(payload.getList(0));
 		BdfDictionary props = payload.getDictionary(1);
 		Map<TransportId, TransportProperties> properties =
 				clientHelper.parseAndValidateTransportPropertiesMap(props);
 		byte[] signature = payload.getRaw(2);
 		checkLength(signature, 1, MAX_SIGNATURE_LENGTH);
 		long timestamp = payload.getLong(3);
 		if (timestamp < 0) throw new FormatException();
-		return new ContactInfo(author, properties, signature, timestamp);
+		LOG.info("Received timestamp");
 		return timestamp;
 	}
 	private void sendTransportProperties(BdfWriter w,
 			Map<TransportId, TransportProperties> local) throws IOException {
 		w.writeListStart();
 		for (Entry<TransportId, TransportProperties> e : local.entrySet())
 			w.writeList(BdfList.of(e.getKey().getString(), e.getValue()));
 		w.writeListEnd();
 	}
 	private Map<TransportId, TransportProperties> receiveTransportProperties(
 			BdfReader r) throws IOException {
 		Map<TransportId, TransportProperties> remote = new HashMap<>();
 		r.readListStart();
 		while (!r.hasListEnd()) {
 			r.readListStart();
 			String id = r.readString(MAX_TRANSPORT_ID_LENGTH);
 			if (id.isEmpty()) throw new FormatException();
 			TransportProperties p = new TransportProperties();
 			r.readDictionaryStart();
 			while (!r.hasDictionaryEnd()) {
 				if (p.size() == MAX_PROPERTIES_PER_TRANSPORT)
 					throw new FormatException();
 				String key = r.readString(MAX_PROPERTY_LENGTH);
 				String value = r.readString(MAX_PROPERTY_LENGTH);
 				p.put(key, value);
 			}
 			r.readDictionaryEnd();
 			r.readListEnd();
 			remote.put(new TransportId(id), p);
 		}
 		r.readListEnd();
 		return remote;
 	}
 	private ContactId addContact(Author remoteAuthor, long timestamp,
@@ -301,30 +324,13 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 		return contactId;
 	}
-	private void tryToClose(DuplexTransportConnection conn) {
+	private void tryToClose(DuplexTransportConnection conn, boolean exception) {
 		try {
 			LOG.info("Closing connection");
-			conn.getReader().dispose(true, true);
+			conn.getReader().dispose(exception, true);
-			conn.getWriter().dispose(true);
+			conn.getWriter().dispose(exception);
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 		}
 	}
 	private static class ContactInfo {
 		private final Author author;
 		private final Map<TransportId, TransportProperties> properties;
 		private final byte[] signature;
 		private final long timestamp;
 		private ContactInfo(Author author,
 				Map<TransportId, TransportProperties> properties,
 				byte[] signature, long timestamp) {
 			this.author = author;
 			this.properties = properties;
 			this.signature = signature;
 			this.timestamp = timestamp;
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/contact/ContactManagerImpl.java
@@ -46,7 +46,7 @@ class ContactManagerImpl implements ContactManager {
 			SecretKey master, long timestamp, boolean alice, boolean verified,
 			boolean active) throws DbException {
 		ContactId c = db.addContact(txn, remote, local, verified, active);
-		keyManager.addContact(txn, c, master, timestamp, alice, active);
+		keyManager.addContact(txn, c, master, timestamp, alice);
 		Contact contact = db.getContact(txn, c);
 		for (ContactHook hook : hooks) hook.addingContact(txn, contact);
 		return c;
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoExecutorModule.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoExecutorModule.java
@@ -1,67 +0,0 @@
 package org.briarproject.bramble.crypto;
 import org.briarproject.bramble.TimeLoggingExecutor;
 import org.briarproject.bramble.api.crypto.CryptoExecutor;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ThreadPoolExecutor;
 import javax.inject.Inject;
 import javax.inject.Singleton;
 import dagger.Module;
 import dagger.Provides;
 import static java.util.concurrent.TimeUnit.SECONDS;
@Module
 public class CryptoExecutorModule {
 	public static class EagerSingletons {
 		@Inject
 		@CryptoExecutor
 		ExecutorService cryptoExecutor;
 	}
 	/**
 	 * The maximum number of executor threads.
 	 * <p>
 	 * The number of available processors can change during the lifetime of the
 	 * JVM, so this is just a reasonable guess.
 	 */
 	private static final int MAX_EXECUTOR_THREADS =
 			Math.max(1, Runtime.getRuntime().availableProcessors() - 1);
 	private final ExecutorService cryptoExecutor;
 	public CryptoExecutorModule() {
 		// Use an unbounded queue
 		BlockingQueue<Runnable> queue = new LinkedBlockingQueue<>();
 		// Discard tasks that are submitted during shutdown
 		RejectedExecutionHandler policy =
 				new ThreadPoolExecutor.DiscardPolicy();
 		// Create a limited # of threads and keep them in the pool for 60 secs
 		cryptoExecutor = new TimeLoggingExecutor("CryptoExecutor", 0,
 				MAX_EXECUTOR_THREADS, 60, SECONDS, queue, policy);
 	}
 	@Provides
 	@Singleton
 	@CryptoExecutor
 	ExecutorService provideCryptoExecutorService(
 			LifecycleManager lifecycleManager) {
 		lifecycleManager.registerForShutdown(cryptoExecutor);
 		return cryptoExecutor;
 	}
 	@Provides
 	@CryptoExecutor
 	Executor provideCryptoExecutor() {
 		return cryptoExecutor;
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoModule.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/CryptoModule.java
@@ -1,24 +1,64 @@
 package org.briarproject.bramble.crypto;
 import org.briarproject.bramble.TimeLoggingExecutor;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.crypto.CryptoExecutor;
 import org.briarproject.bramble.api.crypto.KeyAgreementCrypto;
 import org.briarproject.bramble.api.crypto.PasswordStrengthEstimator;
 import org.briarproject.bramble.api.crypto.StreamDecrypterFactory;
 import org.briarproject.bramble.api.crypto.StreamEncrypterFactory;
 import org.briarproject.bramble.api.crypto.TransportCrypto;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.system.SecureRandomProvider;
 import java.security.SecureRandom;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ThreadPoolExecutor;
 import javax.inject.Inject;
 import javax.inject.Provider;
 import javax.inject.Singleton;
 import dagger.Module;
 import dagger.Provides;
 import static java.util.concurrent.TimeUnit.SECONDS;
@Module
 public class CryptoModule {
 	public static class EagerSingletons {
 		@Inject
 		@CryptoExecutor
 		ExecutorService cryptoExecutor;
 	}
 	/**
 	 * The maximum number of executor threads.
 	 * <p>
 	 * The number of available processors can change during the lifetime of the
 	 * JVM, so this is just a reasonable guess.
 	 */
 	private static final int MAX_EXECUTOR_THREADS =
 			Math.max(1, Runtime.getRuntime().availableProcessors() - 1);
 	private final ExecutorService cryptoExecutor;
 	public CryptoModule() {
 		// Use an unbounded queue
 		BlockingQueue<Runnable> queue = new LinkedBlockingQueue<>();
 		// Discard tasks that are submitted during shutdown
 		RejectedExecutionHandler policy =
 				new ThreadPoolExecutor.DiscardPolicy();
 		// Create a limited # of threads and keep them in the pool for 60 secs
 		cryptoExecutor = new TimeLoggingExecutor("CryptoExecutor", 0,
 				MAX_EXECUTOR_THREADS, 60, SECONDS, queue, policy);
 	}
 	@Provides
 	AuthenticatedCipher provideAuthenticatedCipher() {
 		return new XSalsa20Poly1305AuthenticatedCipher();
@@ -63,6 +103,21 @@ public class CryptoModule {
 		return keyAgreementCrypto;
 	}
 	@Provides
 	@Singleton
 	@CryptoExecutor
 	ExecutorService getCryptoExecutorService(
 			LifecycleManager lifecycleManager) {
 		lifecycleManager.registerForShutdown(cryptoExecutor);
 		return cryptoExecutor;
 	}
 	@Provides
 	@CryptoExecutor
 	Executor getCryptoExecutor() {
 		return cryptoExecutor;
 	}
 	@Provides
 	SecureRandom getSecureRandom(CryptoComponent crypto) {
 		return crypto.getSecureRandom();
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/MessageEncrypter.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/MessageEncrypter.java
@@ -152,47 +152,59 @@ public class MessageEncrypter {
 		}
 	}
-	public static void main(String[] args) {
+	public static void main(String[] args) throws Exception {
 		if (args.length < 1) {
 			printUsage();
-			System.exit(1);
+			return;
 		}
 		SecureRandom random = new SecureRandom();
 		MessageEncrypter encrypter = new MessageEncrypter(random);
 		if (args[0].equals("generate")) {
 			if (args.length != 3) {
 				printUsage();
-				System.exit(1);
+				return;
 			}
 			try {
 				generateKeyPair(args[1], args[2]);
 			} catch (Exception e) {
 				e.printStackTrace();
 				System.exit(2);
 			}
 			// Generate a key pair
 			KeyPair keyPair = encrypter.generateKeyPair();
 			PrintStream out = new PrintStream(new FileOutputStream(args[1]));
 			out.print(
 					StringUtils.toHexString(keyPair.getPublic().getEncoded()));
 			out.flush();
 			out.close();
 			out = new PrintStream(new FileOutputStream(args[2]));
 			out.print(
 					StringUtils.toHexString(keyPair.getPrivate().getEncoded()));
 			out.flush();
 			out.close();
 		} else if (args[0].equals("encrypt")) {
 			if (args.length != 2) {
 				printUsage();
-				System.exit(1);
+				return;
 			}
 			try {
 				encryptMessage(args[1]);
 			} catch (Exception e) {
 				e.printStackTrace();
 				System.exit(2);
 			}
 			// Encrypt a decrypted message
 			InputStream in = new FileInputStream(args[1]);
 			byte[] keyBytes = StringUtils.fromHexString(readFully(in).trim());
 			PublicKey publicKey =
 					encrypter.getKeyParser().parsePublicKey(keyBytes);
 			String message = readFully(System.in);
 			byte[] plaintext = message.getBytes(Charset.forName("UTF-8"));
 			byte[] ciphertext = encrypter.encrypt(publicKey, plaintext);
 			System.out.println(AsciiArmour.wrap(ciphertext, LINE_LENGTH));
 		} else if (args[0].equals("decrypt")) {
 			if (args.length != 2) {
 				printUsage();
-				System.exit(1);
+				return;
 			}
 			try {
 				decryptMessage(args[1]);
 			} catch (Exception e) {
 				e.printStackTrace();
 				System.exit(2);
 			}
 			// Decrypt an encrypted message
 			InputStream in = new FileInputStream(args[1]);
 			byte[] keyBytes = StringUtils.fromHexString(readFully(in).trim());
 			PrivateKey privateKey =
 					encrypter.getKeyParser().parsePrivateKey(keyBytes);
 			byte[] ciphertext = AsciiArmour.unwrap(readFully(System.in));
 			byte[] plaintext = encrypter.decrypt(privateKey, ciphertext);
 			System.out.println(new String(plaintext, Charset.forName("UTF-8")));
 		} else {
 			printUsage();
 			System.exit(1);
 		}
 	}
@@ -204,46 +216,6 @@ public class MessageEncrypter {
 		System.err.println("MessageEncrypter decrypt <private_key_file>");
 	}
 	private static void generateKeyPair(String publicKeyFile,
 			String privateKeyFile) throws Exception {
 		SecureRandom random = new SecureRandom();
 		MessageEncrypter encrypter = new MessageEncrypter(random);
 		KeyPair keyPair = encrypter.generateKeyPair();
 		PrintStream out = new PrintStream(new FileOutputStream(publicKeyFile));
 		out.print(StringUtils.toHexString(keyPair.getPublic().getEncoded()));
 		out.flush();
 		out.close();
 		out = new PrintStream(new FileOutputStream(privateKeyFile));
 		out.print(StringUtils.toHexString(keyPair.getPrivate().getEncoded()));
 		out.flush();
 		out.close();
 	}
 	private static void encryptMessage(String publicKeyFile) throws Exception {
 		SecureRandom random = new SecureRandom();
 		MessageEncrypter encrypter = new MessageEncrypter(random);
 		InputStream in = new FileInputStream(publicKeyFile);
 		byte[] keyBytes = StringUtils.fromHexString(readFully(in).trim());
 		PublicKey publicKey =
 				encrypter.getKeyParser().parsePublicKey(keyBytes);
 		String message = readFully(System.in);
 		byte[] plaintext = message.getBytes(Charset.forName("UTF-8"));
 		byte[] ciphertext = encrypter.encrypt(publicKey, plaintext);
 		System.out.println(AsciiArmour.wrap(ciphertext, LINE_LENGTH));
 	}
 	private static void decryptMessage(String privateKeyFile) throws Exception {
 		SecureRandom random = new SecureRandom();
 		MessageEncrypter encrypter = new MessageEncrypter(random);
 		InputStream in = new FileInputStream(privateKeyFile);
 		byte[] keyBytes = StringUtils.fromHexString(readFully(in).trim());
 		PrivateKey privateKey =
 				encrypter.getKeyParser().parsePrivateKey(keyBytes);
 		byte[] ciphertext = AsciiArmour.unwrap(readFully(System.in));
 		byte[] plaintext = encrypter.decrypt(privateKey, ciphertext);
 		System.out.println(new String(plaintext, Charset.forName("UTF-8")));
 	}
 	private static String readFully(InputStream in) throws IOException {
 		String newline = System.getProperty("line.separator");
 		StringBuilder stringBuilder = new StringBuilder();
--- a/bramble-core/src/main/java/org/briarproject/bramble/crypto/Signature.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/crypto/Signature.java
@@ -10,37 +10,37 @@ import java.security.GeneralSecurityException;
 interface Signature {
 	/**
-	 * @see java.security.Signature#initSign(java.security.PrivateKey)
+	 * @see {@link java.security.Signature#initSign(java.security.PrivateKey)}
 	 */
 	void initSign(PrivateKey k) throws GeneralSecurityException;
 	/**
-	 * @see java.security.Signature#initVerify(java.security.PublicKey)
+	 * @see {@link java.security.Signature#initVerify(java.security.PublicKey)}
 	 */
 	void initVerify(PublicKey k) throws GeneralSecurityException;
 	/**
-	 * @see java.security.Signature#update(byte)
+	 * @see {@link java.security.Signature#update(byte)}
 	 */
 	void update(byte b) throws GeneralSecurityException;
 	/**
-	 * @see java.security.Signature#update(byte[])
+	 * @see {@link java.security.Signature#update(byte[])}
 	 */
 	void update(byte[] b) throws GeneralSecurityException;
 	/**
-	 * @see java.security.Signature#update(byte[], int, int)
+	 * @see {@link java.security.Signature#update(byte[], int, int)}
 	 */
 	void update(byte[] b, int off, int len) throws GeneralSecurityException;
 	/**
-	 * @see java.security.Signature#sign()}
+	 * @see {@link java.security.Signature#sign()}
 	 */
 	byte[] sign() throws GeneralSecurityException;
 	/**
-	 * @see java.security.Signature#verify(byte[])
+	 * @see {@link java.security.Signature#verify(byte[])}
 	 */
 	boolean verify(byte[] signature) throws GeneralSecurityException;
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderFactoryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderFactoryImpl.java
@@ -8,7 +8,6 @@ import java.io.InputStream;
 import javax.annotation.concurrent.Immutable;
 import static org.briarproject.bramble.api.data.BdfReader.DEFAULT_MAX_BUFFER_SIZE;
 import static org.briarproject.bramble.api.data.BdfReader.DEFAULT_NESTED_LIMIT;
@Immutable
@@ -17,13 +16,11 @@ class BdfReaderFactoryImpl implements BdfReaderFactory {
 	@Override
 	public BdfReader createReader(InputStream in) {
-		return new BdfReaderImpl(in, DEFAULT_NESTED_LIMIT,
+		return new BdfReaderImpl(in, DEFAULT_NESTED_LIMIT);
 				DEFAULT_MAX_BUFFER_SIZE);
 	}
 	@Override
-	public BdfReader createReader(InputStream in, int nestedLimit,
+	public BdfReader createReader(InputStream in, int nestedLimit) {
-			int maxBufferSize) {
+		return new BdfReaderImpl(in, nestedLimit);
 		return new BdfReaderImpl(in, nestedLimit, maxBufferSize);
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/BdfReaderImpl.java
@@ -37,16 +37,15 @@ class BdfReaderImpl implements BdfReader {
 	private static final byte[] EMPTY_BUFFER = new byte[0];
 	private final InputStream in;
-	private final int nestedLimit, maxBufferSize;
+	private final int nestedLimit;
 	private boolean hasLookahead = false, eof = false;
 	private byte next;
 	private byte[] buf = new byte[8];
-	BdfReaderImpl(InputStream in, int nestedLimit, int maxBufferSize) {
+	BdfReaderImpl(InputStream in, int nestedLimit) {
 		this.in = in;
 		this.nestedLimit = nestedLimit;
 		this.maxBufferSize = maxBufferSize;
 	}
 	private void readLookahead() throws IOException {
@@ -92,8 +91,8 @@ class BdfReaderImpl implements BdfReader {
 		if (hasBoolean()) return readBoolean();
 		if (hasLong()) return readLong();
 		if (hasDouble()) return readDouble();
-		if (hasString()) return readString();
+		if (hasString()) return readString(Integer.MAX_VALUE);
-		if (hasRaw()) return readRaw();
+		if (hasRaw()) return readRaw(Integer.MAX_VALUE);
 		if (hasList()) return readList(level);
 		if (hasDictionary()) return readDictionary(level);
 		throw new FormatException();
@@ -246,11 +245,11 @@ class BdfReaderImpl implements BdfReader {
 	}
 	@Override
-	public String readString() throws IOException {
+	public String readString(int maxLength) throws IOException {
 		if (!hasString()) throw new FormatException();
 		hasLookahead = false;
 		int length = readStringLength();
-		if (length < 0 || length > maxBufferSize) throw new FormatException();
+		if (length < 0 || length > maxLength) throw new FormatException();
 		if (length == 0) return "";
 		readIntoBuffer(length);
 		return new String(buf, 0, length, "UTF-8");
@@ -280,11 +279,11 @@ class BdfReaderImpl implements BdfReader {
 	}
 	@Override
-	public byte[] readRaw() throws IOException {
+	public byte[] readRaw(int maxLength) throws IOException {
 		if (!hasRaw()) throw new FormatException();
 		hasLookahead = false;
 		int length = readRawLength();
-		if (length < 0 || length > maxBufferSize) throw new FormatException();
+		if (length < 0 || length > maxLength) throw new FormatException();
 		if (length == 0) return EMPTY_BUFFER;
 		byte[] b = new byte[length];
 		readIntoBuffer(b, length);
@@ -382,7 +381,7 @@ class BdfReaderImpl implements BdfReader {
 		BdfDictionary dictionary = new BdfDictionary();
 		readDictionaryStart();
 		while (!hasDictionaryEnd())
-			dictionary.put(readString(), readObject(level + 1));
+			dictionary.put(readString(Integer.MAX_VALUE), readObject(level + 1));
 		readDictionaryEnd();
 		return dictionary;
 	}
--- a/bramble-core/src/main/java/org/briarproject/bramble/data/MetadataParserImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/data/MetadataParserImpl.java
@@ -59,8 +59,8 @@ class MetadataParserImpl implements MetadataParser {
 		if (reader.hasBoolean()) return reader.readBoolean();
 		if (reader.hasLong()) return reader.readLong();
 		if (reader.hasDouble()) return reader.readDouble();
-		if (reader.hasString()) return reader.readString();
+		if (reader.hasString()) return reader.readString(Integer.MAX_VALUE);
-		if (reader.hasRaw()) return reader.readRaw();
+		if (reader.hasRaw()) return reader.readRaw(Integer.MAX_VALUE);
 		if (reader.hasList()) return reader.readList();
 		if (reader.hasDictionary()) return reader.readDictionary();
 		throw new FormatException();
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Database.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Database.java
@@ -34,8 +34,8 @@ import javax.annotation.Nullable;
 * A low-level interface to the database (DatabaseComponent provides a
 * high-level interface). Most operations take a transaction argument, which is
 * obtained by calling {@link #startTransaction()}. Every transaction must be
- * terminated by calling either {@link #abortTransaction(Object) abortTransaction(T)} or
+ * terminated by calling either {@link #abortTransaction(T)} or
- * {@link #commitTransaction(Object) commitTransaction(T)}, even if an exception is thrown.
+ * {@link #commitTransaction(T)}, even if an exception is thrown.
 */
@NotNullByDefault
 interface Database<T> {
@@ -125,10 +125,16 @@ interface Database<T> {
 			throws DbException;
 	/**
-	 * Stores the given transport keys for the given contact and returns a
+	 * Stores the given transport keys, optionally binding them to the given
-	 * key set ID.
+	 * contact, and returns a key set ID.
 	 */
-	KeySetId addTransportKeys(T txn, ContactId c, TransportKeys k)
+	KeySetId addTransportKeys(T txn, @Nullable ContactId c, TransportKeys k)
 			throws DbException;
 	/**
 	 * Binds the given keys for the given transport to the given contact.
 	 */
 	void bindTransportKeys(T txn, ContactId c, TransportId t, KeySetId k)
 			throws DbException;
 	/**
@@ -260,8 +266,7 @@ interface Database<T> {
 	 * <p/>
 	 * Read-only.
 	 */
-	Collection<Group> getGroups(T txn, ClientId c, int majorVersion)
+	Collection<Group> getGroups(T txn, ClientId c) throws DbException;
 			throws DbException;
 	/**
 	 * Returns the given group's visibility to the given contact, or
@@ -316,16 +321,16 @@ interface Database<T> {
 			throws DbException;
 	/**
-	 * Returns the IDs of all delivered messages in the given group.
+	 * Returns the IDs of all messages in the given group.
 	 * <p/>
 	 * Read-only.
 	 */
 	Collection<MessageId> getMessageIds(T txn, GroupId g) throws DbException;
 	/**
-	 * Returns the IDs of any delivered messages in the given group with
+	 * Returns the IDs of any messages in the given group with metadata
-	 * metadata that matches all entries in the given query. If the query is
+	 * matching all entries in the given query. If the query is empty, the IDs
-	 * empty, the IDs of all delivered messages are returned.
+	 * of all messages are returned.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -341,9 +346,9 @@ interface Database<T> {
 			throws DbException;
 	/**
-	 * Returns the metadata for any delivered messages in the given group with
+	 * Returns the metadata for any messages in the given group with metadata
-	 * metadata that matches all entries in the given query. If the query is
+	 * matching all entries in the given query. If the query is empty, the
-	 * empty, the metadata for all delivered messages is returned.
+	 * metadata for all messages is returned.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -351,8 +356,7 @@ interface Database<T> {
 			Metadata query) throws DbException;
 	/**
-	 * Returns the metadata for the given delivered or pending message.
+	 * Returns the metadata for the given delivered message.
 	 * This is only meant to be used by the ValidationManager.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -360,7 +364,7 @@ interface Database<T> {
 			throws DbException;
 	/**
-	 * Returns the metadata for the given delivered message.
+	 * Returns the metadata for the given message.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -374,8 +378,8 @@ interface Database<T> {
 	State getMessageState(T txn, MessageId m) throws DbException;
 	/**
-	 * Returns the status of all delivered messages in the given group with
+	 * Returns the status of all messages in the given group with respect
-	 * respect to the given contact.
+	 * to the given contact.
 	 * <p/>
 	 * Read-only.
 	 */
@@ -383,13 +387,11 @@ interface Database<T> {
 			throws DbException;
 	/**
-	 * Returns the status of the given delivered message with respect to the
+	 * Returns the status of the given message with respect to the given
 	 * given contact, or null if the message's group is invisible to the
 	 * contact.
 	 * <p/>
 	 * Read-only.
 	 */
 	@Nullable
 	MessageStatus getMessageStatus(T txn, ContactId c, MessageId m)
 			throws DbException;
@@ -652,7 +654,7 @@ interface Database<T> {
 			throws DbException;
 	/**
-	 * Updates the given transport keys following key rotation.
+	 * Stores the given transport keys, deleting any keys they have replaced.
 	 */
-	void updateTransportKeys(T txn, KeySet ks) throws DbException;
+	void updateTransportKeys(T txn, Collection<KeySet> keys) throws DbException;
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseComponentImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseComponentImpl.java
@@ -234,17 +234,29 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 	}
 	@Override
-	public KeySetId addTransportKeys(Transaction transaction, ContactId c,
+	public KeySetId addTransportKeys(Transaction transaction,
-			TransportKeys k) throws DbException {
+			@Nullable ContactId c, TransportKeys k) throws DbException {
 		if (transaction.isReadOnly()) throw new IllegalArgumentException();
 		T txn = unbox(transaction);
-		if (!db.containsContact(txn, c))
+		if (c != null && !db.containsContact(txn, c))
 			throw new NoSuchContactException();
 		if (!db.containsTransport(txn, k.getTransportId()))
 			throw new NoSuchTransportException();
 		return db.addTransportKeys(txn, c, k);
 	}
 	@Override
 	public void bindTransportKeys(Transaction transaction, ContactId c,
 			TransportId t, KeySetId k) throws DbException {
 		if (transaction.isReadOnly()) throw new IllegalArgumentException();
 		T txn = unbox(transaction);
 		if (!db.containsContact(txn, c))
 			throw new NoSuchContactException();
 		if (!db.containsTransport(txn, t))
 			throw new NoSuchTransportException();
 		db.bindTransportKeys(txn, c, t, k);
 	}
 	@Override
 	public boolean containsContact(Transaction transaction, AuthorId remote,
 			AuthorId local) throws DbException {
@@ -423,10 +435,10 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 	}
 	@Override
-	public Collection<Group> getGroups(Transaction transaction, ClientId c,
+	public Collection<Group> getGroups(Transaction transaction, ClientId c)
-			int majorVersion) throws DbException {
+			throws DbException {
 		T txn = unbox(transaction);
-		return db.getGroups(txn, c, majorVersion);
+		return db.getGroups(txn, c);
 	}
 	@Override
@@ -454,15 +466,6 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 		return db.getLocalAuthors(txn);
 	}
 	@Override
 	public Collection<MessageId> getMessageIds(Transaction transaction,
 			GroupId g) throws DbException {
 		T txn = unbox(transaction);
 		if (!db.containsGroup(txn, g))
 			throw new NoSuchGroupException();
 		return db.getMessageIds(txn, g);
 	}
 	@Override
 	public Collection<MessageId> getMessagesToValidate(Transaction transaction)
 			throws DbException {
@@ -548,13 +551,6 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 			throw new NoSuchContactException();
 		if (!db.containsGroup(txn, g))
 			throw new NoSuchGroupException();
 		if (db.getGroupVisibility(txn, c, g) == INVISIBLE) {
 			// No status rows exist - return default statuses
 			Collection<MessageStatus> statuses = new ArrayList<>();
 			for (MessageId m : db.getMessageIds(txn, g))
 				statuses.add(new MessageStatus(m, c, false, false));
 			return statuses;
 		}
 		return db.getMessageStatus(txn, c, g);
 	}
@@ -566,9 +562,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 			throw new NoSuchContactException();
 		if (!db.containsMessage(txn, m))
 			throw new NoSuchMessageException();
-		MessageStatus status = db.getMessageStatus(txn, c, m);
+		return db.getMessageStatus(txn, c, m);
 		if (status == null) return new MessageStatus(m, c, false, false);
 		return status;
 	}
 	@Override
@@ -909,9 +903,11 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 			Collection<KeySet> keys) throws DbException {
 		if (transaction.isReadOnly()) throw new IllegalArgumentException();
 		T txn = unbox(transaction);
 		Collection<KeySet> filtered = new ArrayList<>();
 		for (KeySet ks : keys) {
 			TransportId t = ks.getTransportKeys().getTransportId();
-			if (db.containsTransport(txn, t)) db.updateTransportKeys(txn, ks);
+			if (db.containsTransport(txn, t)) filtered.add(ks);
 		}
 		db.updateTransportKeys(txn, filtered);
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/JdbcDatabase.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/JdbcDatabase.java
@@ -53,7 +53,6 @@ import java.util.logging.Logger;
 import javax.annotation.Nullable;
 import static java.sql.Types.INTEGER;
 import static java.util.Collections.singletonList;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.api.db.Metadata.REMOVE;
@@ -75,12 +74,7 @@ import static org.briarproject.bramble.db.ExponentialBackoff.calculateExpiry;
 abstract class JdbcDatabase implements Database<Connection> {
 	// Package access for testing
-	static final int CODE_SCHEMA_VERSION = 39;
+	static final int CODE_SCHEMA_VERSION = 36;
 	// Rotation period offsets for incoming transport keys
 	private static final int OFFSET_PREV = -1;
 	private static final int OFFSET_CURR = 0;
 	private static final int OFFSET_NEXT = 1;
 	private static final String CREATE_SETTINGS =
 			"CREATE TABLE settings"
@@ -118,7 +112,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 			"CREATE TABLE groups"
 					+ " (groupId _HASH NOT NULL,"
 					+ " clientId _STRING NOT NULL,"
 					+ " majorVersion INT NOT NULL,"
 					+ " descriptor _BINARY NOT NULL,"
 					+ " PRIMARY KEY (groupId))";
@@ -237,7 +230,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " (transportId _STRING NOT NULL,"
 					+ " keySetId _COUNTER,"
 					+ " rotationPeriod BIGINT NOT NULL,"
-					+ " contactId INT NOT NULL,"
+					+ " contactId INT," // Null if keys are not bound
 					+ " tagKey _SECRET NOT NULL,"
 					+ " headerKey _SECRET NOT NULL,"
 					+ " stream BIGINT NOT NULL,"
@@ -256,13 +249,12 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " (transportId _STRING NOT NULL,"
 					+ " keySetId INT NOT NULL,"
 					+ " rotationPeriod BIGINT NOT NULL,"
-					+ " contactId INT NOT NULL,"
+					+ " contactId INT," // Null if keys are not bound
 					+ " tagKey _SECRET NOT NULL,"
 					+ " headerKey _SECRET NOT NULL,"
 					+ " base BIGINT NOT NULL,"
 					+ " bitmap _BINARY NOT NULL,"
-					+ " periodOffset INT NOT NULL,"
+					+ " PRIMARY KEY (transportId, keySetId, rotationPeriod),"
 					+ " PRIMARY KEY (transportId, keySetId, periodOffset),"
 					+ " FOREIGN KEY (transportId)"
 					+ " REFERENCES transports (transportId)"
 					+ " ON DELETE CASCADE,"
@@ -277,9 +269,9 @@ abstract class JdbcDatabase implements Database<Connection> {
 			"CREATE INDEX IF NOT EXISTS contactsByAuthorId"
 					+ " ON contacts (authorId)";
-	private static final String INDEX_GROUPS_BY_CLIENT_ID_MAJOR_VERSION =
+	private static final String INDEX_GROUPS_BY_CLIENT_ID =
-			"CREATE INDEX IF NOT EXISTS groupsByClientIdMajorVersion"
+			"CREATE INDEX IF NOT EXISTS groupsByClientId"
-					+ " ON groups (clientId, majorVersion)";
+					+ " ON groups (clientId)";
 	private static final String INDEX_MESSAGE_METADATA_BY_GROUP_ID_STATE =
 			"CREATE INDEX IF NOT EXISTS messageMetadataByGroupIdState"
@@ -390,7 +382,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 	// Package access for testing
 	List<Migration<Connection>> getMigrations() {
-		return singletonList(new Migration38_39());
+		return Collections.emptyList();
 	}
 	private void storeSchemaVersion(Connection txn, int version)
@@ -446,7 +438,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 		try {
 			s = txn.createStatement();
 			s.executeUpdate(INDEX_CONTACTS_BY_AUTHOR_ID);
-			s.executeUpdate(INDEX_GROUPS_BY_CLIENT_ID_MAJOR_VERSION);
+			s.executeUpdate(INDEX_GROUPS_BY_CLIENT_ID);
 			s.executeUpdate(INDEX_MESSAGE_METADATA_BY_GROUP_ID_STATE);
 			s.executeUpdate(INDEX_MESSAGE_DEPENDENCIES_BY_DEPENDENCY_ID);
 			s.executeUpdate(INDEX_STATUSES_BY_CONTACT_ID_GROUP_ID);
@@ -614,14 +606,12 @@ abstract class JdbcDatabase implements Database<Connection> {
 	public void addGroup(Connection txn, Group g) throws DbException {
 		PreparedStatement ps = null;
 		try {
-			String sql = "INSERT INTO groups"
+			String sql = "INSERT INTO groups (groupId, clientId, descriptor)"
-					+ " (groupId, clientId, majorVersion, descriptor)"
+					+ " VALUES (?, ?, ?)";
 					+ " VALUES (?, ?, ?, ?)";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, g.getId().getBytes());
 			ps.setString(2, g.getClientId().getString());
-			ps.setInt(3, g.getMajorVersion());
+			ps.setBytes(3, g.getDescriptor());
 			ps.setBytes(4, g.getDescriptor());
 			int affected = ps.executeUpdate();
 			if (affected != 1) throw new DbStateException();
 			ps.close();
@@ -884,7 +874,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 	}
 	@Override
-	public KeySetId addTransportKeys(Connection txn, ContactId c,
+	public KeySetId addTransportKeys(Connection txn, @Nullable ContactId c,
 			TransportKeys k) throws DbException {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
@@ -894,7 +884,8 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " rotationPeriod, tagKey, headerKey, stream, active)"
 					+ " VALUES (?, ?, ?, ?, ?, ?, ?)";
 			ps = txn.prepareStatement(sql);
-			ps.setInt(1, c.getInt());
+			if (c == null) ps.setNull(1, INTEGER);
 			else ps.setInt(1, c.getInt());
 			ps.setString(2, k.getTransportId().getString());
 			OutgoingKeys outCurr = k.getCurrentOutgoingKeys();
 			ps.setLong(3, outCurr.getRotationPeriod());
@@ -917,12 +908,12 @@ abstract class JdbcDatabase implements Database<Connection> {
 			ps.close();
 			// Store the incoming keys
 			sql = "INSERT INTO incomingKeys (keySetId, contactId, transportId,"
-					+ " rotationPeriod, tagKey, headerKey, base, bitmap,"
+					+ " rotationPeriod, tagKey, headerKey, base, bitmap)"
-					+ " periodOffset)"
+					+ " VALUES (?, ?, ?, ?, ?, ?, ?, ?)";
 					+ " VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, keySetId.getInt());
-			ps.setInt(2, c.getInt());
+			if (c == null) ps.setNull(2, INTEGER);
 			else ps.setInt(2, c.getInt());
 			ps.setString(3, k.getTransportId().getString());
 			// Previous rotation period
 			IncomingKeys inPrev = k.getPreviousIncomingKeys();
@@ -931,7 +922,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 			ps.setBytes(6, inPrev.getHeaderKey().getBytes());
 			ps.setLong(7, inPrev.getWindowBase());
 			ps.setBytes(8, inPrev.getWindowBitmap());
 			ps.setInt(9, OFFSET_PREV);
 			ps.addBatch();
 			// Current rotation period
 			IncomingKeys inCurr = k.getCurrentIncomingKeys();
@@ -940,7 +930,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 			ps.setBytes(6, inCurr.getHeaderKey().getBytes());
 			ps.setLong(7, inCurr.getWindowBase());
 			ps.setBytes(8, inCurr.getWindowBitmap());
 			ps.setInt(9, OFFSET_CURR);
 			ps.addBatch();
 			// Next rotation period
 			IncomingKeys inNext = k.getNextIncomingKeys();
@@ -949,7 +938,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 			ps.setBytes(6, inNext.getHeaderKey().getBytes());
 			ps.setLong(7, inNext.getWindowBase());
 			ps.setBytes(8, inNext.getWindowBitmap());
 			ps.setInt(9, OFFSET_NEXT);
 			ps.addBatch();
 			int[] batchAffected = ps.executeBatch();
 			if (batchAffected.length != 3) throw new DbStateException();
@@ -964,6 +952,33 @@ abstract class JdbcDatabase implements Database<Connection> {
 		}
 	}
 	@Override
 	public void bindTransportKeys(Connection txn, ContactId c, TransportId t,
 			KeySetId k) throws DbException {
 		PreparedStatement ps = null;
 		try {
 			String sql = "UPDATE outgoingKeys SET contactId = ?"
 					+ " WHERE keySetId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, c.getInt());
 			ps.setInt(2, k.getInt());
 			int affected = ps.executeUpdate();
 			if (affected < 0) throw new DbStateException();
 			ps.close();
 			sql = "UPDATE incomingKeys SET contactId = ?"
 					+ " WHERE keySetId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, c.getInt());
 			ps.setInt(2, k.getInt());
 			affected = ps.executeUpdate();
 			if (affected < 0) throw new DbStateException();
 			ps.close();
 		} catch (SQLException e) {
 			tryToClose(ps);
 			throw new DbException(e);
 		}
 	}
 	@Override
 	public boolean containsContact(Connection txn, AuthorId remote,
 			AuthorId local) throws DbException {
@@ -1321,18 +1336,17 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT clientId, majorVersion, descriptor"
+			String sql = "SELECT clientId, descriptor FROM groups"
-					+ " FROM groups WHERE groupId = ?";
+					+ " WHERE groupId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, g.getBytes());
 			rs = ps.executeQuery();
 			if (!rs.next()) throw new DbStateException();
 			ClientId clientId = new ClientId(rs.getString(1));
-			int majorVersion = rs.getInt(2);
+			byte[] descriptor = rs.getBytes(2);
 			byte[] descriptor = rs.getBytes(3);
 			rs.close();
 			ps.close();
-			return new Group(g, clientId, majorVersion, descriptor);
+			return new Group(g, clientId, descriptor);
 		} catch (SQLException e) {
 			tryToClose(rs);
 			tryToClose(ps);
@@ -1341,22 +1355,21 @@ abstract class JdbcDatabase implements Database<Connection> {
 	}
 	@Override
-	public Collection<Group> getGroups(Connection txn, ClientId c,
+	public Collection<Group> getGroups(Connection txn, ClientId c)
-			int majorVersion) throws DbException {
+			throws DbException {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
 			String sql = "SELECT groupId, descriptor FROM groups"
-					+ " WHERE clientId = ? AND majorVersion = ?";
+					+ " WHERE clientId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setString(1, c.getString());
 			ps.setInt(2, majorVersion);
 			rs = ps.executeQuery();
 			List<Group> groups = new ArrayList<>();
 			while (rs.next()) {
 				GroupId id = new GroupId(rs.getBytes(1));
 				byte[] descriptor = rs.getBytes(2);
-				groups.add(new Group(id, c, majorVersion, descriptor));
+				groups.add(new Group(id, c, descriptor));
 			}
 			rs.close();
 			ps.close();
@@ -1488,11 +1501,32 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT messageId FROM messages"
+			String sql = "SELECT messageId FROM messages WHERE groupId = ?";
 					+ " WHERE groupId = ? AND state = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, g.getBytes());
-			ps.setInt(2, DELIVERED.getValue());
+			rs = ps.executeQuery();
 			List<MessageId> ids = new ArrayList<>();
 			while (rs.next()) ids.add(new MessageId(rs.getBytes(1)));
 			rs.close();
 			ps.close();
 			return ids;
 		} catch (SQLException e) {
 			tryToClose(rs);
 			tryToClose(ps);
 			throw new DbException(e);
 		}
 	}
 	private Collection<MessageId> getMessageIds(Connection txn, GroupId g,
 			State state) throws DbException {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
 			String sql = "SELECT messageId FROM messages"
 					+ " WHERE state = ? AND groupId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, state.getValue());
 			ps.setBytes(2, g.getBytes());
 			rs = ps.executeQuery();
 			List<MessageId> ids = new ArrayList<>();
 			while (rs.next()) ids.add(new MessageId(rs.getBytes(1)));
@@ -1510,7 +1544,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 	public Collection<MessageId> getMessageIds(Connection txn, GroupId g,
 			Metadata query) throws DbException {
 		// If there are no query terms, return all delivered messages
-		if (query.isEmpty()) return getMessageIds(txn, g);
+		if (query.isEmpty()) return getMessageIds(txn, g, DELIVERED);
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
@@ -1669,11 +1703,10 @@ abstract class JdbcDatabase implements Database<Connection> {
 		ResultSet rs = null;
 		try {
 			String sql = "SELECT messageId, txCount > 0, seen FROM statuses"
-					+ " WHERE groupId = ? AND contactId = ? AND state = ?";
+					+ " WHERE groupId = ? AND contactId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, g.getBytes());
 			ps.setInt(2, c.getInt());
 			ps.setInt(3, DELIVERED.getValue());
 			rs = ps.executeQuery();
 			List<MessageStatus> statuses = new ArrayList<>();
 			while (rs.next()) {
@@ -1693,29 +1726,24 @@ abstract class JdbcDatabase implements Database<Connection> {
 	}
 	@Override
 	@Nullable
 	public MessageStatus getMessageStatus(Connection txn, ContactId c,
 			MessageId m) throws DbException {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
 			String sql = "SELECT txCount > 0, seen FROM statuses"
-					+ " WHERE messageId = ? AND contactId = ? AND state = ?";
+					+ " WHERE messageId = ? AND contactId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, m.getBytes());
 			ps.setInt(2, c.getInt());
 			ps.setInt(3, DELIVERED.getValue());
 			rs = ps.executeQuery();
-			MessageStatus status = null;
+			if (!rs.next()) throw new DbStateException();
-			if (rs.next()) {
+			boolean sent = rs.getBoolean(1);
-				boolean sent = rs.getBoolean(1);
+			boolean seen = rs.getBoolean(2);
 				boolean seen = rs.getBoolean(2);
 				status = new MessageStatus(m, c, sent, seen);
 			}
 			if (rs.next()) throw new DbStateException();
 			rs.close();
 			ps.close();
-			return status;
+			return new MessageStatus(m, c, sent, seen);
 		} catch (SQLException e) {
 			tryToClose(rs);
 			tryToClose(ps);
@@ -2113,7 +2141,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " base, bitmap"
 					+ " FROM incomingKeys"
 					+ " WHERE transportId = ?"
-					+ " ORDER BY keySetId, periodOffset";
+					+ " ORDER BY keySetId, rotationPeriod";
 			ps = txn.prepareStatement(sql);
 			ps.setString(1, t.getString());
 			rs = ps.executeQuery();
@@ -2144,6 +2172,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 				if (inKeys.size() < (i + 1) * 3) throw new DbStateException();
 				KeySetId keySetId = new KeySetId(rs.getInt(1));
 				ContactId contactId = new ContactId(rs.getInt(2));
 				if (rs.wasNull()) contactId = null;
 				long rotationPeriod = rs.getLong(3);
 				SecretKey tagKey = new SecretKey(rs.getBytes(4));
 				SecretKey headerKey = new SecretKey(rs.getBytes(5));
@@ -2534,14 +2563,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 			if (affected != 1) throw new DbStateException();
 			ps.close();
 			// Remove status rows for the messages in the group
-			sql = "DELETE FROM statuses"
+			for (MessageId m : getMessageIds(txn, g)) removeStatus(txn, c, m);
 					+ " WHERE contactId = ? AND groupId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, c.getInt());
 			ps.setBytes(2, g.getBytes());
 			affected = ps.executeUpdate();
 			if (affected < 0) throw new DbStateException();
 			ps.close();
 		} catch (SQLException e) {
 			tryToClose(ps);
 			throw new DbException(e);
@@ -2625,6 +2647,24 @@ abstract class JdbcDatabase implements Database<Connection> {
 		}
 	}
 	private void removeStatus(Connection txn, ContactId c, MessageId m)
 			throws DbException {
 		PreparedStatement ps = null;
 		try {
 			String sql = "DELETE FROM statuses"
 					+ " WHERE messageId = ? AND contactId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, m.getBytes());
 			ps.setInt(2, c.getInt());
 			int affected = ps.executeUpdate();
 			if (affected != 1) throw new DbStateException();
 			ps.close();
 		} catch (SQLException e) {
 			tryToClose(ps);
 			throw new DbException(e);
 		}
 	}
 	@Override
 	public void removeTransport(Connection txn, TransportId t)
 			throws DbException {
@@ -2904,69 +2944,12 @@ abstract class JdbcDatabase implements Database<Connection> {
 	}
 	@Override
-	public void updateTransportKeys(Connection txn, KeySet ks)
+	public void updateTransportKeys(Connection txn, Collection<KeySet> keys)
 			throws DbException {
-		PreparedStatement ps = null;
+		for (KeySet ks : keys) {
 		try {
 			// Update the outgoing keys
 			String sql = "UPDATE outgoingKeys SET rotationPeriod = ?,"
 					+ " tagKey = ?, headerKey = ?, stream = ?"
 					+ " WHERE transportId = ? AND keySetId = ?";
 			ps = txn.prepareStatement(sql);
 			TransportKeys k = ks.getTransportKeys();
-			OutgoingKeys outCurr = k.getCurrentOutgoingKeys();
+			removeTransportKeys(txn, k.getTransportId(), ks.getKeySetId());
-			ps.setLong(1, outCurr.getRotationPeriod());
+			addTransportKeys(txn, ks.getContactId(), k);
 			ps.setBytes(2, outCurr.getTagKey().getBytes());
 			ps.setBytes(3, outCurr.getHeaderKey().getBytes());
 			ps.setLong(4, outCurr.getStreamCounter());
 			ps.setString(5, k.getTransportId().getString());
 			ps.setInt(6, ks.getKeySetId().getInt());
 			int affected = ps.executeUpdate();
 			if (affected < 0 || affected > 1) throw new DbStateException();
 			ps.close();
 			// Update the incoming keys
 			sql = "UPDATE incomingKeys SET rotationPeriod = ?,"
 					+ " tagKey = ?, headerKey = ?, base = ?, bitmap = ?"
 					+ " WHERE transportId = ? AND keySetId = ?"
 					+ " AND periodOffset = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setString(6, k.getTransportId().getString());
 			ps.setInt(7, ks.getKeySetId().getInt());
 			// Previous rotation period
 			IncomingKeys inPrev = k.getPreviousIncomingKeys();
 			ps.setLong(1, inPrev.getRotationPeriod());
 			ps.setBytes(2, inPrev.getTagKey().getBytes());
 			ps.setBytes(3, inPrev.getHeaderKey().getBytes());
 			ps.setLong(4, inPrev.getWindowBase());
 			ps.setBytes(5, inPrev.getWindowBitmap());
 			ps.setInt(8, OFFSET_PREV);
 			ps.addBatch();
 			// Current rotation period
 			IncomingKeys inCurr = k.getCurrentIncomingKeys();
 			ps.setLong(1, inCurr.getRotationPeriod());
 			ps.setBytes(2, inCurr.getTagKey().getBytes());
 			ps.setBytes(3, inCurr.getHeaderKey().getBytes());
 			ps.setLong(4, inCurr.getWindowBase());
 			ps.setBytes(5, inCurr.getWindowBitmap());
 			ps.setInt(8, OFFSET_CURR);
 			ps.addBatch();
 			// Next rotation period
 			IncomingKeys inNext = k.getNextIncomingKeys();
 			ps.setLong(1, inNext.getRotationPeriod());
 			ps.setBytes(2, inNext.getTagKey().getBytes());
 			ps.setBytes(3, inNext.getHeaderKey().getBytes());
 			ps.setLong(4, inNext.getWindowBase());
 			ps.setBytes(5, inNext.getWindowBitmap());
 			ps.setInt(8, OFFSET_NEXT);
 			ps.addBatch();
 			int[] batchAffected = ps.executeBatch();
 			if (batchAffected.length != 3) throw new DbStateException();
 			for (int rows : batchAffected)
 				if (rows < 0 || rows > 1) throw new DbStateException();
 			ps.close();
 		} catch (SQLException e) {
 			tryToClose(ps);
 			throw new DbException(e);
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration38_39.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration38_39.java
@@ -1,54 +0,0 @@
 package org.briarproject.bramble.db;
 import org.briarproject.bramble.api.db.DbException;
 import java.sql.Connection;
 import java.sql.SQLException;
 import java.sql.Statement;
 import java.util.logging.Logger;
 import javax.annotation.Nullable;
 import static java.util.logging.Level.WARNING;
 class Migration38_39 implements Migration<Connection> {
 	private static final Logger LOG =
 			Logger.getLogger(Migration38_39.class.getName());
 	@Override
 	public int getStartVersion() {
 		return 38;
 	}
 	@Override
 	public int getEndVersion() {
 		return 39;
 	}
 	@Override
 	public void migrate(Connection txn) throws DbException {
 		Statement s = null;
 		try {
 			s = txn.createStatement();
 			// Add not null constraints
 			s.execute("ALTER TABLE outgoingKeys"
 					+ " ALTER COLUMN contactId"
 					+ " SET NOT NULL");
 			s.execute("ALTER TABLE incomingKeys"
 					+ " ALTER COLUMN contactId"
 					+ " SET NOT NULL");
 		} catch (SQLException e) {
 			tryToClose(s);
 			throw new DbException(e);
 		}
 	}
 	private void tryToClose(@Nullable Statement s) {
 		try {
 			if (s != null) s.close();
 		} catch (SQLException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementConnector.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementConnector.java
@@ -13,8 +13,6 @@ import org.briarproject.bramble.api.plugin.PluginManager;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexPlugin;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
 import java.io.IOException;
 import java.io.InputStream;
@@ -46,8 +44,6 @@ class KeyAgreementConnector {
 	private final KeyAgreementCrypto keyAgreementCrypto;
 	private final PluginManager pluginManager;
 	private final ConnectionChooser connectionChooser;
 	private final RecordReaderFactory recordReaderFactory;
 	private final RecordWriterFactory recordWriterFactory;
 	private final List<KeyAgreementListener> listeners =
 			new CopyOnWriteArrayList<>();
@@ -58,15 +54,11 @@ class KeyAgreementConnector {
 	KeyAgreementConnector(Callbacks callbacks,
 			KeyAgreementCrypto keyAgreementCrypto, PluginManager pluginManager,
-			ConnectionChooser connectionChooser,
+			ConnectionChooser connectionChooser) {
 			RecordReaderFactory recordReaderFactory,
 			RecordWriterFactory recordWriterFactory) {
 		this.callbacks = callbacks;
 		this.keyAgreementCrypto = keyAgreementCrypto;
 		this.pluginManager = pluginManager;
 		this.connectionChooser = connectionChooser;
 		this.recordReaderFactory = recordReaderFactory;
 		this.recordWriterFactory = recordWriterFactory;
 	}
 	Payload listen(KeyPair localKeyPair) {
@@ -127,8 +119,7 @@ class KeyAgreementConnector {
 			KeyAgreementConnection chosen =
 					connectionChooser.poll(CONNECTION_TIMEOUT);
 			if (chosen == null) return null;
-			return new KeyAgreementTransport(recordReaderFactory,
+			return new KeyAgreementTransport(chosen);
 					recordWriterFactory, chosen);
 		} catch (InterruptedException e) {
 			LOG.info("Interrupted while waiting for connection");
 			Thread.currentThread().interrupt();
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTaskImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTaskImpl.java
@@ -14,13 +14,10 @@ import org.briarproject.bramble.api.keyagreement.event.KeyAgreementFailedEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementFinishedEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementListeningEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementStartedEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementStoppedListeningEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementWaitingEvent;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.plugin.PluginManager;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
 import java.io.IOException;
 import java.util.logging.Logger;
@@ -51,17 +48,14 @@ class KeyAgreementTaskImpl extends Thread implements KeyAgreementTask,
 	KeyAgreementTaskImpl(CryptoComponent crypto,
 			KeyAgreementCrypto keyAgreementCrypto, EventBus eventBus,
 			PayloadEncoder payloadEncoder, PluginManager pluginManager,
-			ConnectionChooser connectionChooser,
+			ConnectionChooser connectionChooser) {
 			RecordReaderFactory recordReaderFactory,
 			RecordWriterFactory recordWriterFactory) {
 		this.crypto = crypto;
 		this.keyAgreementCrypto = keyAgreementCrypto;
 		this.eventBus = eventBus;
 		this.payloadEncoder = payloadEncoder;
 		localKeyPair = crypto.generateAgreementKeyPair();
 		connector = new KeyAgreementConnector(this, keyAgreementCrypto,
-				pluginManager, connectionChooser, recordReaderFactory,
+				pluginManager, connectionChooser);
 				recordWriterFactory);
 	}
 	@Override
@@ -77,7 +71,6 @@ class KeyAgreementTaskImpl extends Thread implements KeyAgreementTask,
 		if (localPayload != null) {
 			if (remotePayload == null) connector.stopListening();
 			else interrupt();
 			eventBus.broadcast(new KeyAgreementStoppedListeningEvent());
 		}
 	}
--- a/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTransport.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/keyagreement/KeyAgreementTransport.java
@@ -4,12 +4,9 @@ import org.briarproject.bramble.api.keyagreement.KeyAgreementConnection;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
-import org.briarproject.bramble.api.record.Record;
+import org.briarproject.bramble.util.ByteUtils;
 import org.briarproject.bramble.api.record.RecordReader;
 import org.briarproject.bramble.api.record.RecordReaderFactory;
 import org.briarproject.bramble.api.record.RecordWriter;
 import org.briarproject.bramble.api.record.RecordWriterFactory;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -17,6 +14,8 @@ import java.util.logging.Logger;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.PROTOCOL_VERSION;
 import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.RECORD_HEADER_LENGTH;
 import static org.briarproject.bramble.api.keyagreement.KeyAgreementConstants.RECORD_HEADER_PAYLOAD_LENGTH_OFFSET;
 import static org.briarproject.bramble.api.keyagreement.RecordTypes.ABORT;
 import static org.briarproject.bramble.api.keyagreement.RecordTypes.CONFIRM;
 import static org.briarproject.bramble.api.keyagreement.RecordTypes.KEY;
@@ -31,17 +30,14 @@ class KeyAgreementTransport {
 			Logger.getLogger(KeyAgreementTransport.class.getName());
 	private final KeyAgreementConnection kac;
-	private final RecordReader reader;
+	private final InputStream in;
-	private final RecordWriter writer;
+	private final OutputStream out;
-	KeyAgreementTransport(RecordReaderFactory recordReaderFactory,
+	KeyAgreementTransport(KeyAgreementConnection kac)
 			RecordWriterFactory recordWriterFactory, KeyAgreementConnection kac)
 			throws IOException {
 		this.kac = kac;
-		InputStream in = kac.getConnection().getReader().getInputStream();
+		in = kac.getConnection().getReader().getInputStream();
-		reader = recordReaderFactory.createRecordReader(in);
+		out = kac.getConnection().getWriter().getOutputStream();
 		OutputStream out = kac.getConnection().getWriter().getOutputStream();
 		writer = recordWriterFactory.createRecordWriter(out);
 	}
 	public DuplexTransportConnection getConnection() {
@@ -78,8 +74,9 @@ class KeyAgreementTransport {
 		tryToClose(exception);
 	}
-	private void tryToClose(boolean exception) {
+	public void tryToClose(boolean exception) {
 		try {
 			LOG.info("Closing connection");
 			kac.getConnection().getReader().dispose(exception, true);
 			kac.getConnection().getWriter().dispose(exception);
 		} catch (IOException e) {
@@ -88,27 +85,59 @@ class KeyAgreementTransport {
 	}
 	private void writeRecord(byte type, byte[] payload) throws IOException {
-		writer.writeRecord(new Record(PROTOCOL_VERSION, type, payload));
+		byte[] recordHeader = new byte[RECORD_HEADER_LENGTH];
-		writer.flush();
+		recordHeader[0] = PROTOCOL_VERSION;
 		recordHeader[1] = type;
 		ByteUtils.writeUint16(payload.length, recordHeader,
 				RECORD_HEADER_PAYLOAD_LENGTH_OFFSET);
 		out.write(recordHeader);
 		out.write(payload);
 		out.flush();
 	}
 	private byte[] readRecord(byte expectedType) throws AbortException {
 		while (true) {
 			byte[] header = readHeader();
 			byte version = header[0], type = header[1];
 			int len = ByteUtils.readUint16(header,
 					RECORD_HEADER_PAYLOAD_LENGTH_OFFSET);
 			// Reject unrecognised protocol version
 			if (version != PROTOCOL_VERSION) throw new AbortException(false);
 			if (type == ABORT) throw new AbortException(true);
 			if (type == expectedType) {
 				try {
 					return readData(len);
 				} catch (IOException e) {
 					throw new AbortException(e);
 				}
 			}
 			// Reject recognised but unexpected record type
 			if (type == KEY || type == CONFIRM) throw new AbortException(false);
 			// Skip unrecognised record type
 			try {
-				Record record = reader.readRecord();
+				readData(len);
 				// Reject unrecognised protocol version
 				if (record.getProtocolVersion() != PROTOCOL_VERSION)
 					throw new AbortException(false);
 				byte type = record.getRecordType();
 				if (type == ABORT) throw new AbortException(true);
 				if (type == expectedType) return record.getPayload();
 				// Reject recognised but unexpected record type
 				if (type == KEY || type == CONFIRM)
 					throw new AbortException(false);
 				// Skip unrecognised record type
 			} catch (IOException e) {
 				throw new AbortException(e);
 			}
 		}
 	}
 	private byte[] readHeader() throws AbortException {
 		try {
 			return readData(RECORD_HEADER_LENGTH);
 		} catch (IOException e) {
 			throw new AbortException(e);
 		}
 	}
 	private byte[] readData(int len) throws IOException {
 		byte[] data = new byte[len];
 		int offset = 0;
 		while (offset < data.length) {
 			int read = in.read(data, offset, data.length - offset);
 			if (read == -1) throw new EOFException();
 			offset += read;
 		}
 		return data;
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/ConnectionManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/ConnectionManagerImpl.java
@@ -14,12 +14,12 @@ import org.briarproject.bramble.api.sync.SyncSessionFactory;
 import org.briarproject.bramble.api.transport.KeyManager;
 import org.briarproject.bramble.api.transport.StreamContext;
 import org.briarproject.bramble.api.transport.StreamReaderFactory;
 import org.briarproject.bramble.api.transport.StreamWriter;
 import org.briarproject.bramble.api.transport.StreamWriterFactory;
 import java.io.EOFException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.concurrent.Executor;
 import java.util.logging.Logger;
@@ -101,7 +101,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 	private SyncSession createSimplexOutgoingSession(StreamContext ctx,
 			TransportConnectionWriter w) throws IOException {
-		StreamWriter streamWriter = streamWriterFactory.createStreamWriter(
+		OutputStream streamWriter = streamWriterFactory.createStreamWriter(
 				w.getOutputStream(), ctx);
 		return syncSessionFactory.createSimplexOutgoingSession(
 				ctx.getContactId(), w.getMaxLatency(), streamWriter);
@@ -109,7 +109,7 @@ class ConnectionManagerImpl implements ConnectionManager {
 	private SyncSession createDuplexOutgoingSession(StreamContext ctx,
 			TransportConnectionWriter w) throws IOException {
-		StreamWriter streamWriter = streamWriterFactory.createStreamWriter(
+		OutputStream streamWriter = streamWriterFactory.createStreamWriter(
 				w.getOutputStream(), ctx);
 		return syncSessionFactory.createDuplexOutgoingSession(
 				ctx.getContactId(), w.getMaxLatency(), w.getMaxIdleTime(),
@@ -300,8 +300,8 @@ class ConnectionManagerImpl implements ConnectionManager {
 		}
 		private void disposeReader(boolean exception, boolean recognised) {
-			// Interrupt the outgoing session so it finishes cleanly
+			if (exception && outgoingSession != null)
-			if (outgoingSession != null) outgoingSession.interrupt();
+				outgoingSession.interrupt();
 			try {
 				reader.dispose(exception, recognised);
 			} catch (IOException e) {
@@ -310,8 +310,6 @@ class ConnectionManagerImpl implements ConnectionManager {
 		}
 		private void disposeWriter(boolean exception) {
 			// Interrupt the incoming session if an exception occurred,
 			// otherwise wait for the end of stream marker
 			if (exception && incomingSession != null)
 				incomingSession.interrupt();
 			try {
@@ -409,8 +407,8 @@ class ConnectionManagerImpl implements ConnectionManager {
 		}
 		private void disposeReader(boolean exception, boolean recognised) {
-			// Interrupt the outgoing session so it finishes cleanly
+			if (exception && outgoingSession != null)
-			if (outgoingSession != null) outgoingSession.interrupt();
+				outgoingSession.interrupt();
 			try {
 				reader.dispose(exception, recognised);
 			} catch (IOException e) {
@@ -419,8 +417,6 @@ class ConnectionManagerImpl implements ConnectionManager {
 		}
 		private void disposeWriter(boolean exception) {
 			// Interrupt the incoming session if an exception occurred,
 			// otherwise wait for the end of stream marker
 			if (exception && incomingSession != null)
 				incomingSession.interrupt();
 			try {
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/ConnectionRegistryImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/ConnectionRegistryImpl.java
@@ -106,7 +106,7 @@ class ConnectionRegistryImpl implements ConnectionRegistry {
 			if (m == null) return Collections.emptyList();
 			List<ContactId> ids = new ArrayList<>(m.keySet());
 			if (LOG.isLoggable(INFO))
-				LOG.info(ids.size() + " contacts connected: " + t);
+				LOG.info(ids.size() + " contacts connected");
 			return ids;
 		} finally {
 			lock.unlock();
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/PluginManagerImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/PluginManagerImpl.java
@@ -8,7 +8,6 @@ import org.briarproject.bramble.api.lifecycle.Service;
 import org.briarproject.bramble.api.lifecycle.ServiceException;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.ConnectionManager;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.Plugin;
 import org.briarproject.bramble.api.plugin.PluginCallback;
 import org.briarproject.bramble.api.plugin.PluginConfig;
@@ -30,19 +29,17 @@ import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.settings.Settings;
 import org.briarproject.bramble.api.settings.SettingsManager;
-import org.briarproject.bramble.api.system.Clock;
+import org.briarproject.bramble.api.ui.UiCallback;
 import org.briarproject.bramble.api.system.Scheduler;
 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.concurrent.ConcurrentHashMap;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.logging.Logger;
@@ -60,15 +57,12 @@ class PluginManagerImpl implements PluginManager, Service {
 			Logger.getLogger(PluginManagerImpl.class.getName());
 	private final Executor ioExecutor;
 	private final ScheduledExecutorService scheduler;
 	private final EventBus eventBus;
 	private final PluginConfig pluginConfig;
 	private final ConnectionManager connectionManager;
 	private final ConnectionRegistry connectionRegistry;
 	private final SettingsManager settingsManager;
 	private final TransportPropertyManager transportPropertyManager;
-	private final SecureRandom random;
+	private final UiCallback uiCallback;
 	private final Clock clock;
 	private final Map<TransportId, Plugin> plugins;
 	private final List<SimplexPlugin> simplexPlugins;
 	private final List<DuplexPlugin> duplexPlugins;
@@ -76,41 +70,27 @@ class PluginManagerImpl implements PluginManager, Service {
 	private final AtomicBoolean used = new AtomicBoolean(false);
 	@Inject
-	PluginManagerImpl(@IoExecutor Executor ioExecutor,
+	PluginManagerImpl(@IoExecutor Executor ioExecutor, EventBus eventBus,
 			@Scheduler ScheduledExecutorService scheduler, EventBus eventBus,
 			PluginConfig pluginConfig, ConnectionManager connectionManager,
 			ConnectionRegistry connectionRegistry,
 			SettingsManager settingsManager,
 			TransportPropertyManager transportPropertyManager,
-			SecureRandom random, Clock clock) {
+			UiCallback uiCallback) {
 		this.ioExecutor = ioExecutor;
 		this.scheduler = scheduler;
 		this.eventBus = eventBus;
 		this.pluginConfig = pluginConfig;
 		this.connectionManager = connectionManager;
 		this.connectionRegistry = connectionRegistry;
 		this.settingsManager = settingsManager;
 		this.transportPropertyManager = transportPropertyManager;
-		this.random = random;
+		this.uiCallback = uiCallback;
 		this.clock = clock;
 		plugins = new ConcurrentHashMap<>();
 		simplexPlugins = new CopyOnWriteArrayList<>();
 		duplexPlugins = new CopyOnWriteArrayList<>();
 		startLatches = new ConcurrentHashMap<>();
 	}
 	@Override
-	public void startService() {
+	public void startService() throws ServiceException {
 		if (used.getAndSet(true)) throw new IllegalStateException();
 		// Instantiate the poller
 		if (pluginConfig.shouldPoll()) {
 			LOG.info("Starting poller");
 			Poller poller = new Poller(ioExecutor, scheduler, connectionManager,
 					connectionRegistry, this, transportPropertyManager, random,
 					clock);
 			eventBus.addListener(poller);
 		}
 		// Instantiate the simplex plugins and start them asynchronously
 		LOG.info("Starting simplex plugins");
 		for (SimplexPluginFactory f : pluginConfig.getSimplexFactories()) {
@@ -293,6 +273,26 @@ class PluginManagerImpl implements PluginManager, Service {
 			}
 		}
 		@Override
 		public Map<ContactId, TransportProperties> getRemoteProperties() {
 			try {
 				return transportPropertyManager.getRemoteProperties(id);
 			} catch (DbException e) {
 				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 				return Collections.emptyMap();
 			}
 		}
 		@Override
 		public TransportProperties getRemoteProperties(ContactId c) {
 			try {
 				return transportPropertyManager.getRemoteProperties(c, id);
 			} catch (DbException e) {
 				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 				return new TransportProperties();
 			}
 		}
 		@Override
 		public void mergeSettings(Settings s) {
 			try {
@@ -311,6 +311,21 @@ class PluginManagerImpl implements PluginManager, Service {
 			}
 		}
 		@Override
 		public int showChoice(String[] options, String... message) {
 			return uiCallback.showChoice(options, message);
 		}
 		@Override
 		public boolean showConfirmationMessage(String... message) {
 			return uiCallback.showConfirmationMessage(message);
 		}
 		@Override
 		public void showMessage(String... message) {
 			uiCallback.showMessage(message);
 		}
 		@Override
 		public void transportEnabled() {
 			eventBus.broadcast(new TransportEnabledEvent(id));
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/PluginModule.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/PluginModule.java
@@ -1,10 +1,18 @@
 package org.briarproject.bramble.plugin;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
 import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.plugin.BackoffFactory;
 import org.briarproject.bramble.api.plugin.ConnectionManager;
 import org.briarproject.bramble.api.plugin.ConnectionRegistry;
 import org.briarproject.bramble.api.plugin.PluginManager;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.Scheduler;
 import java.security.SecureRandom;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ScheduledExecutorService;
 import javax.inject.Inject;
 import javax.inject.Singleton;
@@ -18,6 +26,8 @@ public class PluginModule {
 	public static class EagerSingletons {
 		@Inject
 		PluginManager pluginManager;
 		@Inject
 		Poller poller;
 	}
 	@Provides
@@ -25,6 +35,19 @@ public class PluginModule {
 		return new BackoffFactoryImpl();
 	}
 	@Provides
 	@Singleton
 	Poller providePoller(@IoExecutor Executor ioExecutor,
 			@Scheduler ScheduledExecutorService scheduler,
 			ConnectionManager connectionManager,
 			ConnectionRegistry connectionRegistry, PluginManager pluginManager,
 			SecureRandom random, Clock clock, EventBus eventBus) {
 		Poller poller = new Poller(ioExecutor, scheduler, connectionManager,
 				connectionRegistry, pluginManager, random, clock);
 		eventBus.addListener(poller);
 		return poller;
 	}
 	@Provides
 	@Singleton
 	ConnectionManager provideConnectionManager(
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/Poller.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/Poller.java
@@ -2,7 +2,6 @@ package org.briarproject.bramble.plugin;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.contact.event.ContactStatusChangedEvent;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.event.Event;
 import org.briarproject.bramble.api.event.EventListener;
 import org.briarproject.bramble.api.lifecycle.IoExecutor;
@@ -20,17 +19,12 @@ import org.briarproject.bramble.api.plugin.event.ConnectionOpenedEvent;
 import org.briarproject.bramble.api.plugin.event.TransportDisabledEvent;
 import org.briarproject.bramble.api.plugin.event.TransportEnabledEvent;
 import org.briarproject.bramble.api.plugin.simplex.SimplexPlugin;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.system.Scheduler;
 import java.security.SecureRandom;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.Executor;
 import java.util.concurrent.Future;
 import java.util.concurrent.ScheduledExecutorService;
@@ -39,10 +33,10 @@ import java.util.concurrent.locks.ReentrantLock;
 import java.util.logging.Logger;
 import javax.annotation.concurrent.ThreadSafe;
 import javax.inject.Inject;
 import static java.util.concurrent.TimeUnit.MILLISECONDS;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
@ThreadSafe
@NotNullByDefault
@@ -55,30 +49,26 @@ class Poller implements EventListener {
 	private final ConnectionManager connectionManager;
 	private final ConnectionRegistry connectionRegistry;
 	private final PluginManager pluginManager;
 	private final TransportPropertyManager transportPropertyManager;
 	private final SecureRandom random;
 	private final Clock clock;
 	private final Lock lock;
 	private final Map<TransportId, ScheduledPollTask> tasks; // Locking: lock
 	private final Set<TransportId> polling; // Locking: lock
 	@Inject
 	Poller(@IoExecutor Executor ioExecutor,
 			@Scheduler ScheduledExecutorService scheduler,
 			ConnectionManager connectionManager,
 			ConnectionRegistry connectionRegistry, PluginManager pluginManager,
 			TransportPropertyManager transportPropertyManager,
 			SecureRandom random, Clock clock) {
 		this.ioExecutor = ioExecutor;
 		this.scheduler = scheduler;
 		this.connectionManager = connectionManager;
 		this.connectionRegistry = connectionRegistry;
 		this.pluginManager = pluginManager;
 		this.transportPropertyManager = transportPropertyManager;
 		this.random = random;
 		this.clock = clock;
 		lock = new ReentrantLock();
 		tasks = new HashMap<>();
 		polling = new HashSet<>();
 	}
 	@Override
@@ -130,15 +120,10 @@ class Poller implements EventListener {
 	private void connectToContact(ContactId c, SimplexPlugin p) {
 		ioExecutor.execute(() -> {
 			TransportId t = p.getId();
-			if (connectionRegistry.isConnected(c, t)) return;
+			if (!connectionRegistry.isConnected(c, t)) {
-			try {
+				TransportConnectionWriter w = p.createWriter(c);
 				TransportProperties props =
 						transportPropertyManager.getRemoteProperties(c, t);
 				TransportConnectionWriter w = p.createWriter(props);
 				if (w != null)
 					connectionManager.manageOutgoingConnection(c, t, w);
 			} catch (DbException e) {
 				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			}
 		});
 	}
@@ -146,15 +131,10 @@ class Poller implements EventListener {
 	private void connectToContact(ContactId c, DuplexPlugin p) {
 		ioExecutor.execute(() -> {
 			TransportId t = p.getId();
-			if (connectionRegistry.isConnected(c, t)) return;
+			if (!connectionRegistry.isConnected(c, t)) {
-			try {
+				DuplexTransportConnection d = p.createConnection(c);
 				TransportProperties props =
 						transportPropertyManager.getRemoteProperties(c, t);
 				DuplexTransportConnection d = p.createConnection(props);
 				if (d != null)
 					connectionManager.manageOutgoingConnection(c, t, d);
 			} catch (DbException e) {
 				if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			}
 		});
 	}
@@ -206,17 +186,7 @@ class Poller implements EventListener {
 	private void poll(Plugin p) {
 		TransportId t = p.getId();
 		if (LOG.isLoggable(INFO)) LOG.info("Polling plugin " + t);
-		try {
+		p.poll(connectionRegistry.getConnectedContacts(t));
 			Map<ContactId, TransportProperties> remote =
 					transportPropertyManager.getRemoteProperties(t);
 			Collection<ContactId> connected =
 					connectionRegistry.getConnectedContacts(t);
 			remote = new HashMap<>(remote);
 			remote.keySet().removeAll(connected);
 			if (!remote.isEmpty()) p.poll(remote);
 		} catch (DbException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 		}
 	}
 	private class ScheduledPollTask {
@@ -245,33 +215,20 @@ class Poller implements EventListener {
 		@Override
 		@IoExecutor
 		public void run() {
 			TransportId t = plugin.getId();
 			boolean shouldPoll;
 			lock.lock();
 			try {
 				TransportId t = plugin.getId();
 				ScheduledPollTask scheduled = tasks.get(t);
 				if (scheduled != null && scheduled.task != this)
 					return; // Replaced by another task
 				tasks.remove(t);
 				// Don't poll again if last poll is still running
 				shouldPoll = polling.add(t);
 			} finally {
 				lock.unlock();
 			}
 			int delay = plugin.getPollingInterval();
 			if (randomiseNext) delay = (int) (delay * random.nextDouble());
 			schedule(plugin, delay, false);
-			if (shouldPoll) {
+			poll(plugin);
 				poll(plugin);
 			} else if (LOG.isLoggable(INFO)) {
 				LOG.info("Last poll for " + t + " is still running");
 			}
 			lock.lock();
 			try {
 				polling.remove(t);
 			} finally {
 				lock.unlock();
 			}
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothConnectionLimiter.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothConnectionLimiter.java
@@ -1,47 +0,0 @@
 package org.briarproject.bramble.plugin.bluetooth;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
@NotNullByDefault
 interface BluetoothConnectionLimiter {
 	/**
 	 * Informs the limiter that key agreement has started.
 	 */
 	void keyAgreementStarted();
 	/**
 	 * Informs the limiter that key agreement has ended.
 	 */
 	void keyAgreementEnded();
 	/**
 	 * Returns true if a contact connection can be opened. This method does not
 	 * need to be called for key agreement connections.
 	 */
 	boolean canOpenContactConnection();
 	/**
 	 * Informs the limiter that a contact connection has been opened. The
 	 * limiter may close the new connection if key agreement is in progress.
 	 * <p/>
 	 * Returns false if the limiter has closed the new connection.
 	 */
 	boolean contactConnectionOpened(DuplexTransportConnection conn);
 	/**
 	 * Informs the limiter that a key agreement connection has been opened.
 	 */
 	void keyAgreementConnectionOpened(DuplexTransportConnection conn);
 	/**
 	 * Informs the limiter that the given connection has been closed.
 	 */
 	void connectionClosed(DuplexTransportConnection conn);
 	/**
 	 * Informs the limiter that all connections have been closed.
 	 */
 	void allConnectionsClosed();
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothConnectionLimiterImpl.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothConnectionLimiterImpl.java
@@ -1,115 +0,0 @@
 package org.briarproject.bramble.plugin.bluetooth;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.duplex.DuplexTransportConnection;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.logging.Logger;
 import javax.annotation.concurrent.ThreadSafe;
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
@NotNullByDefault
@ThreadSafe
 class BluetoothConnectionLimiterImpl implements BluetoothConnectionLimiter {
 	private static final Logger LOG =
 			Logger.getLogger(BluetoothConnectionLimiterImpl.class.getName());
 	private final Object lock = new Object();
 	// The following are locking: lock
 	private final LinkedList<DuplexTransportConnection> connections =
 			new LinkedList<>();
 	private boolean keyAgreementInProgress = false;
 	@Override
 	public void keyAgreementStarted() {
 		List<DuplexTransportConnection> close;
 		synchronized (lock) {
 			keyAgreementInProgress = true;
 			close = new ArrayList<>(connections);
 			connections.clear();
 		}
 		if (LOG.isLoggable(INFO)) {
 			LOG.info("Key agreement started, closing " + close.size() +
 					" connections");
 		}
 		for (DuplexTransportConnection conn : close) tryToClose(conn);
 	}
 	@Override
 	public void keyAgreementEnded() {
 		synchronized (lock) {
 			keyAgreementInProgress = false;
 		}
 		LOG.info("Key agreement ended");
 	}
 	@Override
 	public boolean canOpenContactConnection() {
 		synchronized (lock) {
 			if (keyAgreementInProgress) {
 				LOG.info("Can't open contact connection during key agreement");
 				return false;
 			} else {
 				LOG.info("Can open contact connection");
 				return true;
 			}
 		}
 	}
 	@Override
 	public boolean contactConnectionOpened(DuplexTransportConnection conn) {
 		boolean accept = true;
 		synchronized (lock) {
 			if (keyAgreementInProgress) {
 				LOG.info("Refusing contact connection during key agreement");
 				accept = false;
 			} else {
 				LOG.info("Accepting contact connection");
 				connections.add(conn);
 			}
 		}
 		if (!accept) tryToClose(conn);
 		return accept;
 	}
 	@Override
 	public void keyAgreementConnectionOpened(DuplexTransportConnection conn) {
 		synchronized (lock) {
 			LOG.info("Accepting key agreement connection");
 			connections.add(conn);
 		}
 	}
 	private void tryToClose(DuplexTransportConnection conn) {
 		try {
 			conn.getWriter().dispose(false);
 			conn.getReader().dispose(false, false);
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 		}
 	}
 	@Override
 	public void connectionClosed(DuplexTransportConnection conn) {
 		synchronized (lock) {
 			connections.remove(conn);
 			if (LOG.isLoggable(INFO))
 				LOG.info("Connection closed, " + connections.size() + " open");
 		}
 	}
 	@Override
 	public void allConnectionsClosed() {
 		synchronized (lock) {
 			connections.clear();
 			LOG.info("All connections closed");
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothPlugin.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/bluetooth/BluetoothPlugin.java
@@ -7,8 +7,6 @@ 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.keyagreement.event.KeyAgreementListeningEvent;
 import org.briarproject.bramble.api.keyagreement.event.KeyAgreementStoppedListeningEvent;
 import org.briarproject.bramble.api.nullsafety.MethodsNotNullByDefault;
 import org.briarproject.bramble.api.nullsafety.ParametersNotNullByDefault;
 import org.briarproject.bramble.api.plugin.Backoff;
@@ -26,10 +24,9 @@ import org.briarproject.bramble.util.StringUtils;
 import java.io.IOException;
 import java.security.SecureRandom;
-import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.UUID;
 import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -54,14 +51,6 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 	private static final Logger LOG =
 			Logger.getLogger(BluetoothPlugin.class.getName());
 	/**
 	 * How many milliseconds to pause between connection attempts when
 	 * polling, to avoid interfering with other Bluetooth or wifi connections.
 	 */
 	private static final int POLLING_PAUSE_MS = 1000;
 	final BluetoothConnectionLimiter connectionLimiter;
 	private final Executor ioExecutor;
 	private final SecureRandom secureRandom;
 	private final Backoff backoff;
@@ -102,10 +91,8 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 	abstract DuplexTransportConnection connectTo(String address, String uuid)
 			throws IOException;
-	BluetoothPlugin(BluetoothConnectionLimiter connectionLimiter,
+	BluetoothPlugin(Executor ioExecutor, SecureRandom secureRandom,
 			Executor ioExecutor, SecureRandom secureRandom,
 			Backoff backoff, DuplexPluginCallback callback, int maxLatency) {
 		this.connectionLimiter = connectionLimiter;
 		this.ioExecutor = ioExecutor;
 		this.secureRandom = secureRandom;
 		this.backoff = backoff;
@@ -123,7 +110,6 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 	void onAdapterDisabled() {
 		LOG.info("Bluetooth disabled");
 		tryToClose(socket);
 		connectionLimiter.allConnectionsClosed();
 		callback.transportDisabled();
 	}
@@ -227,8 +213,7 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 				return;
 			}
 			backoff.reset();
-			if (connectionLimiter.contactConnectionOpened(conn))
+			callback.incomingConnectionCreated(conn);
 				callback.incomingConnectionCreated(conn);
 			if (!running) return;
 		}
 	}
@@ -257,42 +242,28 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 	}
 	@Override
-	public void poll(Map<ContactId, TransportProperties> contacts) {
+	public void poll(Collection<ContactId> connected) {
 		if (!isRunning() || !shouldAllowContactConnections()) return;
 		backoff.increment();
-		// Try to connect to known devices in a random order
+		// Try to connect to known devices in parallel
-		List<ContactId> keys = new ArrayList<>(contacts.keySet());
+		Map<ContactId, TransportProperties> remote =
-		Collections.shuffle(keys);
+				callback.getRemoteProperties();
-		ioExecutor.execute(() -> {
+		for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
-			boolean first = true;
+			ContactId c = e.getKey();
-			for (ContactId c : keys) {
+			if (connected.contains(c)) continue;
 			String address = e.getValue().get(PROP_ADDRESS);
 			if (StringUtils.isNullOrEmpty(address)) continue;
 			String uuid = e.getValue().get(PROP_UUID);
 			if (StringUtils.isNullOrEmpty(uuid)) continue;
 			ioExecutor.execute(() -> {
 				if (!isRunning() || !shouldAllowContactConnections()) return;
 				if (!connectionLimiter.canOpenContactConnection()) return;
 				TransportProperties p = contacts.get(c);
 				String address = p.get(PROP_ADDRESS);
 				if (StringUtils.isNullOrEmpty(address)) continue;
 				String uuid = p.get(PROP_UUID);
 				if (StringUtils.isNullOrEmpty(uuid)) continue;
 				// Pause between connection attempts
 				if (first) {
 					first = false;
 				} else {
 					try {
 						Thread.sleep(POLLING_PAUSE_MS);
 					} catch (InterruptedException ex) {
 						LOG.info("Interrupted while polling");
 						Thread.currentThread().interrupt();
 						return;
 					}
 				}
 				DuplexTransportConnection conn = connect(address, uuid);
 				if (conn != null) {
 					backoff.reset();
-					if (connectionLimiter.contactConnectionOpened(conn))
+					callback.outgoingConnectionCreated(c, conn);
 						callback.outgoingConnectionCreated(c, conn);
 				}
-			}
+			});
-		});
+		}
 	}
 	@Nullable
@@ -327,17 +298,14 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 	}
 	@Override
-	public DuplexTransportConnection createConnection(TransportProperties p) {
+	public DuplexTransportConnection createConnection(ContactId c) {
 		if (!isRunning() || !shouldAllowContactConnections()) return null;
-		if (!connectionLimiter.canOpenContactConnection()) return null;
+		TransportProperties p = callback.getRemoteProperties(c);
 		String address = p.get(PROP_ADDRESS);
 		if (StringUtils.isNullOrEmpty(address)) return null;
 		String uuid = p.get(PROP_UUID);
 		if (StringUtils.isNullOrEmpty(uuid)) return null;
-		DuplexTransportConnection conn = connect(address, uuid);
+		return connect(address, uuid);
 		if (conn == null) return null;
 		// TODO: Why don't we reset the backoff here?
 		return connectionLimiter.contactConnectionOpened(conn) ? conn : null;
 	}
 	@Override
@@ -387,9 +355,7 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 		String uuid = UUID.nameUUIDFromBytes(commitment).toString();
 		if (LOG.isLoggable(INFO))
 			LOG.info("Connecting to key agreement UUID " + uuid);
-		DuplexTransportConnection conn = connect(address, uuid);
+		return connect(address, uuid);
 		if (conn != null) connectionLimiter.keyAgreementConnectionOpened(conn);
 		return conn;
 	}
 	private String parseAddress(BdfList descriptor) throws FormatException {
@@ -410,10 +376,6 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 			SettingsUpdatedEvent s = (SettingsUpdatedEvent) e;
 			if (s.getNamespace().equals(ID.getString()))
 				ioExecutor.execute(this::onSettingsUpdated);
 		} else if (e instanceof KeyAgreementListeningEvent) {
 			ioExecutor.execute(connectionLimiter::keyAgreementStarted);
 		} else if (e instanceof KeyAgreementStoppedListeningEvent) {
 			ioExecutor.execute(connectionLimiter::keyAgreementEnded);
 		}
 	}
@@ -446,7 +408,6 @@ abstract class BluetoothPlugin<SS> implements DuplexPlugin, EventListener {
 		public KeyAgreementConnection accept() throws IOException {
 			DuplexTransportConnection conn = acceptConnection(ss);
 			if (LOG.isLoggable(INFO)) LOG.info(ID + ": Incoming connection");
 			connectionLimiter.keyAgreementConnectionOpened(conn);
 			return new KeyAgreementConnection(conn, ID);
 		}
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FilePlugin.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FilePlugin.java
@@ -1,21 +1,27 @@
 package org.briarproject.bramble.plugin.file;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.plugin.TransportConnectionReader;
 import org.briarproject.bramble.api.plugin.TransportConnectionWriter;
 import org.briarproject.bramble.api.plugin.simplex.SimplexPlugin;
 import org.briarproject.bramble.api.plugin.simplex.SimplexPluginCallback;
 import org.briarproject.bramble.api.properties.TransportProperties;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.util.Collection;
 import java.util.Locale;
 import java.util.concurrent.Executor;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.logging.Logger;
 import javax.annotation.Nullable;
 import static java.util.logging.Level.WARNING;
-import static org.briarproject.bramble.api.plugin.FileConstants.PROP_PATH;
+import static org.briarproject.bramble.api.transport.TransportConstants.MIN_STREAM_LENGTH;
 import static org.briarproject.bramble.util.StringUtils.isNullOrEmpty;
@NotNullByDefault
 abstract class FilePlugin implements SimplexPlugin {
@@ -23,15 +29,25 @@ abstract class FilePlugin implements SimplexPlugin {
 	private static final Logger LOG =
 			Logger.getLogger(FilePlugin.class.getName());
 	protected final Executor ioExecutor;
 	protected final SimplexPluginCallback callback;
 	protected final int maxLatency;
 	protected final AtomicBoolean used = new AtomicBoolean(false);
-	protected abstract void writerFinished(File f, boolean exception);
+	protected volatile boolean running = false;
-	protected abstract void readerFinished(File f, boolean exception,
+	@Nullable
-			boolean recognised);
+	protected abstract File chooseOutputDirectory();
-	FilePlugin(SimplexPluginCallback callback, int maxLatency) {
+	protected abstract Collection<File> findFilesByName(String filename);
 	protected abstract void writerFinished(File f);
 	protected abstract void readerFinished(File f);
 	protected FilePlugin(Executor ioExecutor, SimplexPluginCallback callback,
 			int maxLatency) {
 		this.ioExecutor = ioExecutor;
 		this.callback = callback;
 		this.maxLatency = maxLatency;
 	}
@@ -42,36 +58,81 @@ abstract class FilePlugin implements SimplexPlugin {
 	}
 	@Override
-	public TransportConnectionReader createReader(TransportProperties p) {
+	public int getMaxIdleTime() {
-		if (!isRunning()) return null;
+		return Integer.MAX_VALUE; // We don't need keepalives
-		String path = p.get(PROP_PATH);
+	}
-		if (isNullOrEmpty(path)) return null;
+
 	@Override
 	public boolean isRunning() {
 		return running;
 	}
 	@Override
 	public TransportConnectionReader createReader(ContactId c) {
 		return null;
 	}
 	@Override
 	public TransportConnectionWriter createWriter(ContactId c) {
 		if (!running) return null;
 		return createWriter(createConnectionFilename());
 	}
 	private String createConnectionFilename() {
 		StringBuilder s = new StringBuilder(12);
 		for (int i = 0; i < 8; i++) s.append((char) ('a' + Math.random() * 26));
 		s.append(".dat");
 		return s.toString();
 	}
 	// Package access for testing
 	boolean isPossibleConnectionFilename(String filename) {
 		return filename.toLowerCase(Locale.US).matches("[a-z]{8}\\.dat");
 	}
 	@Nullable
 	private TransportConnectionWriter createWriter(String filename) {
 		if (!running) return null;
 		File dir = chooseOutputDirectory();
 		if (dir == null || !dir.exists() || !dir.isDirectory()) return null;
 		File f = new File(dir, filename);
 		try {
-			File file = new File(path);
+			long capacity = dir.getFreeSpace();
-			FileInputStream in = new FileInputStream(file);
+			if (capacity < MIN_STREAM_LENGTH) return null;
-			return new FileTransportReader(file, in, this);
+			OutputStream out = new FileOutputStream(f);
 			return new FileTransportWriter(f, out, capacity, this);
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			f.delete();
 			return null;
 		}
 	}
-	@Override
+	protected void createReaderFromFile(File f) {
-	public TransportConnectionWriter createWriter(TransportProperties p) {
+		if (!running) return;
-		if (!isRunning()) return null;
+		ioExecutor.execute(new ReaderCreator(f));
-		String path = p.get(PROP_PATH);
+	}
-		if (isNullOrEmpty(path)) return null;
+
-		try {
+	private class ReaderCreator implements Runnable {
-			File file = new File(path);
+
-			if (!file.exists() && !file.createNewFile()) {
+		private final File file;
-				LOG.info("Failed to create file");
+
-				return null;
+		private ReaderCreator(File file) {
 			this.file = file;
 		}
 		@Override
 		public void run() {
 			if (isPossibleConnectionFilename(file.getName())) {
 				try {
 					FileInputStream in = new FileInputStream(file);
 					callback.readerCreated(new FileTransportReader(file, in,
 							FilePlugin.this));
 				} catch (IOException e) {
 					if (LOG.isLoggable(WARNING))
 						LOG.log(WARNING, e.toString(), e);
 				}
 			}
 			FileOutputStream out = new FileOutputStream(file);
 			return new FileTransportWriter(file, out, this);
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 			return null;
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FileTransportReader.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FileTransportReader.java
@@ -38,6 +38,9 @@ class FileTransportReader implements TransportConnectionReader {
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 		}
-		plugin.readerFinished(file, exception, recognised);
+		if (recognised) {
 			file.delete();
 			plugin.readerFinished(file);
 		}
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FileTransportWriter.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/file/FileTransportWriter.java
@@ -18,11 +18,14 @@ class FileTransportWriter implements TransportConnectionWriter {
 	private final File file;
 	private final OutputStream out;
 	private final long capacity;
 	private final FilePlugin plugin;
-	FileTransportWriter(File file, OutputStream out, FilePlugin plugin) {
+	FileTransportWriter(File file, OutputStream out, long capacity,
 			FilePlugin plugin) {
 		this.file = file;
 		this.out = out;
 		this.capacity = capacity;
 		this.plugin = plugin;
 	}
@@ -36,6 +39,11 @@ class FileTransportWriter implements TransportConnectionWriter {
 		return plugin.getMaxIdleTime();
 	}
 	@Override
 	public long getCapacity() {
 		return capacity;
 	}
 	@Override
 	public OutputStream getOutputStream() {
 		return out;
@@ -48,6 +56,7 @@ class FileTransportWriter implements TransportConnectionWriter {
 		} catch (IOException e) {
 			if (LOG.isLoggable(WARNING)) LOG.log(WARNING, e.toString(), e);
 		}
-		plugin.writerFinished(file, exception);
+		if (exception) file.delete();
 		else plugin.writerFinished(file);
 	}
 }
--- a/bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/TcpPlugin.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/plugin/tcp/TcpPlugin.java
@@ -207,16 +207,20 @@ abstract class TcpPlugin implements DuplexPlugin {
 	}
 	@Override
-	public void poll(Map<ContactId, TransportProperties> contacts) {
+	public void poll(Collection<ContactId> connected) {
 		if (!isRunning()) return;
 		backoff.increment();
-		for (Entry<ContactId, TransportProperties> e : contacts.entrySet()) {
+		Map<ContactId, TransportProperties> remote =
-			connectAndCallBack(e.getKey(), e.getValue());
+				callback.getRemoteProperties();
 		for (Entry<ContactId, TransportProperties> e : remote.entrySet()) {
 			ContactId c = e.getKey();
 			if (!connected.contains(c)) connectAndCallBack(c, e.getValue());
 		}
 	}
 	private void connectAndCallBack(ContactId c, TransportProperties p) {
 		ioExecutor.execute(() -> {
 			if (!isRunning()) return;
 			DuplexTransportConnection d = createConnection(p);
 			if (d != null) {
 				backoff.reset();
@@ -226,8 +230,13 @@ abstract class TcpPlugin implements DuplexPlugin {
 	}
 	@Override
-	public DuplexTransportConnection createConnection(TransportProperties p) {
+	public DuplexTransportConnection createConnection(ContactId c) {
 		if (!isRunning()) return null;
 		return createConnection(callback.getRemoteProperties(c));
 	}
 	@Nullable
 	private DuplexTransportConnection createConnection(TransportProperties p) {
 		for (InetSocketAddress remote : getRemoteSocketAddresses(p)) {
 			if (!isConnectable(remote)) {
 				if (LOG.isLoggable(INFO)) {
--- a/bramble-core/src/main/java/org/briarproject/bramble/properties/PropertiesModule.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/properties/PropertiesModule.java
@@ -7,7 +7,6 @@ import org.briarproject.bramble.api.lifecycle.LifecycleManager;
 import org.briarproject.bramble.api.properties.TransportPropertyManager;
 import org.briarproject.bramble.api.sync.ValidationManager;
 import org.briarproject.bramble.api.system.Clock;
 import org.briarproject.bramble.api.versioning.ClientVersioningManager;
 import javax.inject.Inject;
 import javax.inject.Singleton;
@@ -16,8 +15,6 @@ import dagger.Module;
 import dagger.Provides;
 import static org.briarproject.bramble.api.properties.TransportPropertyManager.CLIENT_ID;
 import static org.briarproject.bramble.api.properties.TransportPropertyManager.MAJOR_VERSION;
 import static org.briarproject.bramble.api.properties.TransportPropertyManager.MINOR_VERSION;
@Module
 public class PropertiesModule {
@@ -36,8 +33,7 @@ public class PropertiesModule {
 			Clock clock) {
 		TransportPropertyValidator validator = new TransportPropertyValidator(
 				clientHelper, metadataEncoder, clock);
-		validationManager.registerMessageValidator(CLIENT_ID, MAJOR_VERSION,
+		validationManager.registerMessageValidator(CLIENT_ID, validator);
 				validator);
 		return validator;
 	}
@@ -46,14 +42,11 @@ public class PropertiesModule {
 	TransportPropertyManager getTransportPropertyManager(
 			LifecycleManager lifecycleManager,
 			ValidationManager validationManager, ContactManager contactManager,
 			ClientVersioningManager clientVersioningManager,
 			TransportPropertyManagerImpl transportPropertyManager) {
 		lifecycleManager.registerClient(transportPropertyManager);
-		validationManager.registerIncomingMessageHook(CLIENT_ID, MAJOR_VERSION,
+		validationManager.registerIncomingMessageHook(CLIENT_ID,
 				transportPropertyManager);
 		contactManager.registerContactHook(transportPropertyManager);
 		clientVersioningManager.registerClient(CLIENT_ID, MAJOR_VERSION,
 				MINOR_VERSION, transportPropertyManager);
 		return transportPropertyManager;
 	}
 }
--- a/Show More
+++ b/Show More