Use a versioned format for encoding authors.

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

@@ -15,6 +15,8 @@ import org.briarproject.bramble.api.db.DatabaseComponent;
 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.identity.Author;
+import org.briarproject.bramble.api.identity.AuthorFactory;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
@@ -32,7 +34,12 @@ import java.util.Map.Entry;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
+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.sync.SyncConstants.MESSAGE_HEADER_LENGTH;
+import static org.briarproject.bramble.util.ValidationUtils.checkLength;
+import static org.briarproject.bramble.util.ValidationUtils.checkSize;
 
 @Immutable
 @NotNullByDefault
@@ -51,12 +58,14 @@ class ClientHelperImpl implements ClientHelper {
 	private final MetadataParser metadataParser;
 	private final MetadataEncoder metadataEncoder;
 	private final CryptoComponent crypto;
+	private final AuthorFactory authorFactory;
 
 	@Inject
 	ClientHelperImpl(DatabaseComponent db, MessageFactory messageFactory,
 			BdfReaderFactory bdfReaderFactory,
 			BdfWriterFactory bdfWriterFactory, MetadataParser metadataParser,
-			MetadataEncoder metadataEncoder, CryptoComponent crypto) {
+			MetadataEncoder metadataEncoder, CryptoComponent crypto,
+			AuthorFactory authorFactory) {
 		this.db = db;
 		this.messageFactory = messageFactory;
 		this.bdfReaderFactory = bdfReaderFactory;
@@ -64,6 +73,7 @@ class ClientHelperImpl implements ClientHelper {
 		this.metadataParser = metadataParser;
 		this.metadataEncoder = metadataEncoder;
 		this.crypto = crypto;
+		this.authorFactory = authorFactory;
 	}
 
 	@Override
@@ -355,4 +365,16 @@ class ClientHelperImpl implements ClientHelper {
 		}
 	}
 
+	@Override
+	public Author parseAndValidateAuthor(BdfList author)
+			throws FormatException {
+		checkSize(author, 3);
+		int formatVersion = author.getLong(0).intValue();
+		if (formatVersion != FORMAT_VERSION) throw new FormatException();
+		String name = author.getString(1);
+		checkLength(name, 1, MAX_AUTHOR_NAME_LENGTH);
+		byte[] publicKey = author.getRaw(2);
+		checkLength(publicKey, 1, MAX_PUBLIC_KEY_LENGTH);
+		return authorFactory.createAuthor(formatVersion, name, publicKey);
+	}
 }

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

@@ -2,14 +2,6 @@ package org.briarproject.bramble.client;
 
 import org.briarproject.bramble.api.client.ClientHelper;
 import org.briarproject.bramble.api.client.ContactGroupFactory;
-import org.briarproject.bramble.api.crypto.CryptoComponent;
-import org.briarproject.bramble.api.data.BdfReaderFactory;
-import org.briarproject.bramble.api.data.BdfWriterFactory;
-import org.briarproject.bramble.api.data.MetadataEncoder;
-import org.briarproject.bramble.api.data.MetadataParser;
-import org.briarproject.bramble.api.db.DatabaseComponent;
-import org.briarproject.bramble.api.sync.GroupFactory;
-import org.briarproject.bramble.api.sync.MessageFactory;
 
 import dagger.Module;
 import dagger.Provides;
@@ -18,19 +10,14 @@ import dagger.Provides;
 public class ClientModule {
 
 	@Provides
-	ClientHelper provideClientHelper(DatabaseComponent db,
-			MessageFactory messageFactory, BdfReaderFactory bdfReaderFactory,
-			BdfWriterFactory bdfWriterFactory, MetadataParser metadataParser,
-			MetadataEncoder metadataEncoder, CryptoComponent cryptoComponent) {
-		return new ClientHelperImpl(db, messageFactory, bdfReaderFactory,
-				bdfWriterFactory, metadataParser, metadataEncoder,
-				cryptoComponent);
+	ClientHelper provideClientHelper(ClientHelperImpl clientHelper) {
+		return clientHelper;
 	}
 
 	@Provides
-	ContactGroupFactory provideContactGroupFactory(GroupFactory groupFactory,
-			ClientHelper clientHelper) {
-		return new ContactGroupFactoryImpl(groupFactory, clientHelper);
+	ContactGroupFactory provideContactGroupFactory(
+			ContactGroupFactoryImpl contactGroupFactory) {
+		return contactGroupFactory;
 	}
 
 }

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

@@ -43,6 +43,7 @@ import javax.inject.Inject;
 
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
+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;
@@ -227,6 +228,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 
 		// Write the name, public key and signature
 		w.writeListStart();
+		w.writeLong(localAuthor.getFormatVersion());
 		w.writeString(localAuthor.getName());
 		w.writeRaw(localAuthor.getPublicKey());
 		w.writeRaw(sig);
@@ -236,11 +238,16 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 
 	private Author receivePseudonym(BdfReader r, byte[] nonce)
 			throws GeneralSecurityException, IOException {
-		// Read the name, public key and signature
+		// 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
@@ -249,7 +256,7 @@ class ContactExchangeTaskImpl extends Thread implements ContactExchangeTask {
 				LOG.info("Invalid signature");
 			throw new GeneralSecurityException();
 		}
-		return authorFactory.createAuthor(name, publicKey);
+		return authorFactory.createAuthor(formatVersion, name, publicKey);
 	}
 
 	private void sendTimestamp(BdfWriter w, long timestamp)

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

@@ -81,6 +81,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 	private static final String CREATE_LOCAL_AUTHORS =
 			"CREATE TABLE localAuthors"
 					+ " (authorId _HASH NOT NULL,"
+					+ " formatVersion INT NOT NULL,"
 					+ " name _STRING NOT NULL,"
 					+ " publicKey _BINARY NOT NULL,"
 					+ " privateKey _BINARY NOT NULL,"
@@ -91,6 +92,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 			"CREATE TABLE contacts"
 					+ " (contactId _COUNTER,"
 					+ " authorId _HASH NOT NULL,"
+					+ " formatVersion INT NOT NULL,"
 					+ " name _STRING NOT NULL,"
 					+ " publicKey _BINARY NOT NULL,"
 					+ " localAuthorId _HASH NOT NULL,"
@@ -513,16 +515,18 @@ abstract class JdbcDatabase implements Database<Connection> {
 		try {
 			// Create a contact row
 			String sql = "INSERT INTO contacts"
-					+ " (authorId, name, publicKey, localAuthorId,"
+					+ " (authorId, formatVersion, name, publicKey,"
+					+ " localAuthorId,"
 					+ " verified, active)"
-					+ " VALUES (?, ?, ?, ?, ?, ?)";
+					+ " VALUES (?, ?, ?, ?, ?, ?, ?)";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, remote.getId().getBytes());
-			ps.setString(2, remote.getName());
-			ps.setBytes(3, remote.getPublicKey());
-			ps.setBytes(4, local.getBytes());
-			ps.setBoolean(5, verified);
-			ps.setBoolean(6, active);
+			ps.setInt(2, remote.getFormatVersion());
+			ps.setString(3, remote.getName());
+			ps.setBytes(4, remote.getPublicKey());
+			ps.setBytes(5, local.getBytes());
+			ps.setBoolean(6, verified);
+			ps.setBoolean(7, active);
 			int affected = ps.executeUpdate();
 			if (affected != 1) throw new DbStateException();
 			ps.close();
@@ -590,14 +594,16 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		try {
 			String sql = "INSERT INTO localAuthors"
-					+ " (authorId, name, publicKey, privateKey, created)"
-					+ " VALUES (?, ?, ?, ?, ?)";
+					+ " (authorId, formatVersion, name, publicKey,"
+					+ " privateKey, created)"
+					+ " VALUES (?, ?, ?, ?, ?, ?)";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, a.getId().getBytes());
-			ps.setString(2, a.getName());
-			ps.setBytes(3, a.getPublicKey());
-			ps.setBytes(4, a.getPrivateKey());
-			ps.setLong(5, a.getTimeCreated());
+			ps.setInt(2, a.getFormatVersion());
+			ps.setString(3, a.getName());
+			ps.setBytes(4, a.getPublicKey());
+			ps.setBytes(5, a.getPrivateKey());
+			ps.setLong(6, a.getTimeCreated());
 			int affected = ps.executeUpdate();
 			if (affected != 1) throw new DbStateException();
 			ps.close();
@@ -1013,7 +1019,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT authorId, name, publicKey,"
+			String sql = "SELECT authorId, formatVersion, name, publicKey,"
 					+ " localAuthorId, verified, active"
 					+ " FROM contacts"
 					+ " WHERE contactId = ?";
@@ -1022,14 +1028,16 @@ abstract class JdbcDatabase implements Database<Connection> {
 			rs = ps.executeQuery();
 			if (!rs.next()) throw new DbStateException();
 			AuthorId authorId = new AuthorId(rs.getBytes(1));
-			String name = rs.getString(2);
-			byte[] publicKey = rs.getBytes(3);
-			AuthorId localAuthorId = new AuthorId(rs.getBytes(4));
-			boolean verified = rs.getBoolean(5);
-			boolean active = rs.getBoolean(6);
+			int formatVersion = rs.getInt(2);
+			String name = rs.getString(3);
+			byte[] publicKey = rs.getBytes(4);
+			AuthorId localAuthorId = new AuthorId(rs.getBytes(5));
+			boolean verified = rs.getBoolean(6);
+			boolean active = rs.getBoolean(7);
 			rs.close();
 			ps.close();
-			Author author = new Author(authorId, name, publicKey);
+			Author author =
+					new Author(authorId, formatVersion, name, publicKey);
 			return new Contact(c, author, localAuthorId, verified, active);
 		} catch (SQLException e) {
 			tryToClose(rs);
@@ -1044,8 +1052,8 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT contactId, authorId, name, publicKey,"
-					+ " localAuthorId, verified, active"
+			String sql = "SELECT contactId, authorId, formatVersion, name,"
+					+ " publicKey, localAuthorId, verified, active"
 					+ " FROM contacts";
 			ps = txn.prepareStatement(sql);
 			rs = ps.executeQuery();
@@ -1053,12 +1061,14 @@ abstract class JdbcDatabase implements Database<Connection> {
 			while (rs.next()) {
 				ContactId contactId = new ContactId(rs.getInt(1));
 				AuthorId authorId = new AuthorId(rs.getBytes(2));
-				String name = rs.getString(3);
-				byte[] publicKey = rs.getBytes(4);
-				Author author = new Author(authorId, name, publicKey);
-				AuthorId localAuthorId = new AuthorId(rs.getBytes(5));
-				boolean verified = rs.getBoolean(6);
-				boolean active = rs.getBoolean(7);
+				int formatVersion = rs.getInt(3);
+				String name = rs.getString(4);
+				byte[] publicKey = rs.getBytes(5);
+				Author author =
+						new Author(authorId, formatVersion, name, publicKey);
+				AuthorId localAuthorId = new AuthorId(rs.getBytes(6));
+				boolean verified = rs.getBoolean(7);
+				boolean active = rs.getBoolean(8);
 				contacts.add(new Contact(contactId, author, localAuthorId,
 						verified, active));
 			}
@@ -1101,7 +1111,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT contactId, name, publicKey,"
+			String sql = "SELECT contactId, formatVersion, name, publicKey,"
 					+ " localAuthorId, verified, active"
 					+ " FROM contacts"
 					+ " WHERE authorId = ?";
@@ -1111,12 +1121,14 @@ abstract class JdbcDatabase implements Database<Connection> {
 			List<Contact> contacts = new ArrayList<>();
 			while (rs.next()) {
 				ContactId c = new ContactId(rs.getInt(1));
-				String name = rs.getString(2);
-				byte[] publicKey = rs.getBytes(3);
-				AuthorId localAuthorId = new AuthorId(rs.getBytes(4));
-				boolean verified = rs.getBoolean(5);
-				boolean active = rs.getBoolean(6);
-				Author author = new Author(remote, name, publicKey);
+				int formatVersion = rs.getInt(2);
+				String name = rs.getString(3);
+				byte[] publicKey = rs.getBytes(4);
+				AuthorId localAuthorId = new AuthorId(rs.getBytes(5));
+				boolean verified = rs.getBoolean(6);
+				boolean active = rs.getBoolean(7);
+				Author author =
+						new Author(remote, formatVersion, name, publicKey);
 				contacts.add(new Contact(c, author, localAuthorId, verified,
 						active));
 			}
@@ -1235,19 +1247,21 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT name, publicKey, privateKey, created"
+			String sql = "SELECT formatVersion, name, publicKey,"
+					+ " privateKey, created"
 					+ " FROM localAuthors"
 					+ " WHERE authorId = ?";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, a.getBytes());
 			rs = ps.executeQuery();
 			if (!rs.next()) throw new DbStateException();
-			String name = rs.getString(1);
-			byte[] publicKey = rs.getBytes(2);
-			byte[] privateKey = rs.getBytes(3);
-			long created = rs.getLong(4);
-			LocalAuthor localAuthor = new LocalAuthor(a, name, publicKey,
-					privateKey, created);
+			int formatVersion = rs.getInt(1);
+			String name = rs.getString(2);
+			byte[] publicKey = rs.getBytes(3);
+			byte[] privateKey = rs.getBytes(4);
+			long created = rs.getLong(5);
+			LocalAuthor localAuthor = new LocalAuthor(a, formatVersion, name,
+					publicKey, privateKey, created);
 			if (rs.next()) throw new DbStateException();
 			rs.close();
 			ps.close();
@@ -1265,19 +1279,21 @@ abstract class JdbcDatabase implements Database<Connection> {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
-			String sql = "SELECT authorId, name, publicKey, privateKey, created"
+			String sql = "SELECT authorId, formatVersion, name, publicKey,"
+					+ " privateKey, created"
 					+ " FROM localAuthors";
 			ps = txn.prepareStatement(sql);
 			rs = ps.executeQuery();
 			List<LocalAuthor> authors = new ArrayList<>();
 			while (rs.next()) {
 				AuthorId authorId = new AuthorId(rs.getBytes(1));
-				String name = rs.getString(2);
-				byte[] publicKey = rs.getBytes(3);
-				byte[] privateKey = rs.getBytes(4);
-				long created = rs.getLong(5);
-				authors.add(new LocalAuthor(authorId, name, publicKey,
-						privateKey, created));
+				int formatVersion = rs.getInt(2);
+				String name = rs.getString(3);
+				byte[] publicKey = rs.getBytes(4);
+				byte[] privateKey = rs.getBytes(5);
+				long created = rs.getLong(6);
+				authors.add(new LocalAuthor(authorId, formatVersion, name,
+						publicKey, privateKey, created));
 			}
 			rs.close();
 			ps.close();

bramble-core/src/main/java/org/briarproject/bramble/identity/AuthorFactoryImpl.java

@@ -1,61 +1,65 @@
 package org.briarproject.bramble.identity;
 
 import org.briarproject.bramble.api.crypto.CryptoComponent;
-import org.briarproject.bramble.api.data.BdfWriter;
-import org.briarproject.bramble.api.data.BdfWriterFactory;
 import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorFactory;
 import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
 import org.briarproject.bramble.api.system.Clock;
-
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
+import org.briarproject.bramble.util.ByteUtils;
+import org.briarproject.bramble.util.StringUtils;
 
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
+import static org.briarproject.bramble.api.identity.Author.FORMAT_VERSION;
+import static org.briarproject.bramble.api.identity.AuthorId.LABEL;
+import static org.briarproject.bramble.util.ByteUtils.INT_32_BYTES;
+
 @Immutable
 @NotNullByDefault
 class AuthorFactoryImpl implements AuthorFactory {
 
 	private final CryptoComponent crypto;
-	private final BdfWriterFactory bdfWriterFactory;
 	private final Clock clock;
 
 	@Inject
-	AuthorFactoryImpl(CryptoComponent crypto, BdfWriterFactory bdfWriterFactory,
-			Clock clock) {
+	AuthorFactoryImpl(CryptoComponent crypto, Clock clock) {
 		this.crypto = crypto;
-		this.bdfWriterFactory = bdfWriterFactory;
 		this.clock = clock;
 	}
 
 	@Override
 	public Author createAuthor(String name, byte[] publicKey) {
-		return new Author(getId(name, publicKey), name, publicKey);
+		return createAuthor(FORMAT_VERSION, name, publicKey);
+	}
+
+	@Override
+	public Author createAuthor(int formatVersion, String name,
+			byte[] publicKey) {
+		AuthorId id = getId(formatVersion, name, publicKey);
+		return new Author(id, formatVersion, name, publicKey);
 	}
 
 	@Override
 	public LocalAuthor createLocalAuthor(String name, byte[] publicKey,
 			byte[] privateKey) {
-		return new LocalAuthor(getId(name, publicKey), name, publicKey,
-				privateKey, clock.currentTimeMillis());
+		return createLocalAuthor(FORMAT_VERSION, name, publicKey, privateKey);
 	}
 
-	private AuthorId getId(String name, byte[] publicKey) {
-		ByteArrayOutputStream out = new ByteArrayOutputStream();
-		BdfWriter w = bdfWriterFactory.createWriter(out);
-		try {
-			w.writeListStart();
-			w.writeString(name);
-			w.writeRaw(publicKey);
-			w.writeListEnd();
-		} catch (IOException e) {
-			// Shouldn't happen with ByteArrayOutputStream
-			throw new RuntimeException(e);
-		}
-		return new AuthorId(crypto.hash(AuthorId.LABEL, out.toByteArray()));
+	@Override
+	public LocalAuthor createLocalAuthor(int formatVersion, String name,
+			byte[] publicKey, byte[] privateKey) {
+		AuthorId id = getId(formatVersion, name, publicKey);
+		return new LocalAuthor(id, formatVersion, name, publicKey, privateKey,
+				clock.currentTimeMillis());
+	}
+
+	private AuthorId getId(int formatVersion, String name, byte[] publicKey) {
+		byte[] formatVersionBytes = new byte[INT_32_BYTES];
+		ByteUtils.writeUint32(formatVersion, formatVersionBytes, 0);
+		return new AuthorId(crypto.hash(LABEL, formatVersionBytes,
+				StringUtils.toUtf8(name), publicKey));
 	}
 }

bramble-core/src/main/java/org/briarproject/bramble/identity/AuthorReader.java

@@ -1,36 +0,0 @@
-package org.briarproject.bramble.identity;
-
-import org.briarproject.bramble.api.FormatException;
-import org.briarproject.bramble.api.data.BdfReader;
-import org.briarproject.bramble.api.data.ObjectReader;
-import org.briarproject.bramble.api.identity.Author;
-import org.briarproject.bramble.api.identity.AuthorFactory;
-import org.briarproject.bramble.api.nullsafety.NotNullByDefault;
-
-import java.io.IOException;
-
-import javax.annotation.concurrent.Immutable;
-
-import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
-import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_PUBLIC_KEY_LENGTH;
-
-@Immutable
-@NotNullByDefault
-class AuthorReader implements ObjectReader<Author> {
-
-	private final AuthorFactory authorFactory;
-
-	AuthorReader(AuthorFactory authorFactory) {
-		this.authorFactory = authorFactory;
-	}
-
-	@Override
-	public Author readObject(BdfReader r) throws IOException {
-		r.readListStart();
-		String name = r.readString(MAX_AUTHOR_NAME_LENGTH);
-		if (name.length() == 0) throw new FormatException();
-		byte[] publicKey = r.readRaw(MAX_PUBLIC_KEY_LENGTH);
-		r.readListEnd();
-		return authorFactory.createAuthor(name, publicKey);
-	}
-}

bramble-core/src/main/java/org/briarproject/bramble/identity/IdentityModule.java

@@ -1,13 +1,7 @@
 package org.briarproject.bramble.identity;
 
-import org.briarproject.bramble.api.crypto.CryptoComponent;
-import org.briarproject.bramble.api.data.BdfWriterFactory;
-import org.briarproject.bramble.api.data.ObjectReader;
-import org.briarproject.bramble.api.db.DatabaseComponent;
-import org.briarproject.bramble.api.identity.Author;
 import org.briarproject.bramble.api.identity.AuthorFactory;
 import org.briarproject.bramble.api.identity.IdentityManager;
-import org.briarproject.bramble.api.system.Clock;
 
 import javax.inject.Inject;
 import javax.inject.Singleton;
@@ -24,19 +18,14 @@ public class IdentityModule {
 	}
 
 	@Provides
-	AuthorFactory provideAuthorFactory(CryptoComponent crypto,
-			BdfWriterFactory bdfWriterFactory, Clock clock) {
-		return new AuthorFactoryImpl(crypto, bdfWriterFactory, clock);
+	AuthorFactory provideAuthorFactory(AuthorFactoryImpl authorFactory) {
+		return authorFactory;
 	}
 
 	@Provides
 	@Singleton
-	IdentityManager provideIdentityModule(DatabaseComponent db) {
-		return new IdentityManagerImpl(db);
-	}
-
-	@Provides
-	ObjectReader<Author> provideAuthorReader(AuthorFactory authorFactory) {
-		return new AuthorReader(authorFactory);
+	IdentityManager provideIdentityManager(
+			IdentityManagerImpl identityManager) {
+		return identityManager;
 	}
 }

bramble-core/src/test/java/org/briarproject/bramble/client/ClientHelperImplTest.java

@@ -15,6 +15,8 @@ import org.briarproject.bramble.api.data.MetadataParser;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.Metadata;
 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.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageFactory;
@@ -31,9 +33,14 @@ import java.security.GeneralSecurityException;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Random;
 
+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.test.TestUtils.getAuthor;
 import static org.briarproject.bramble.test.TestUtils.getRandomBytes;
 import static org.briarproject.bramble.test.TestUtils.getRandomId;
+import static org.briarproject.bramble.util.StringUtils.getRandomString;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.fail;
@@ -54,7 +61,8 @@ public class ClientHelperImplTest extends BrambleTestCase {
 			context.mock(MetadataEncoder.class);
 	private final CryptoComponent cryptoComponent =
 			context.mock(CryptoComponent.class);
-	private final ClientHelper clientHelper;
+	private final AuthorFactory authorFactory =
+			context.mock(AuthorFactory.class);
 
 	private final GroupId groupId = new GroupId(getRandomId());
 	private final BdfDictionary dictionary = new BdfDictionary();
@@ -66,17 +74,15 @@ public class ClientHelperImplTest extends BrambleTestCase {
 	private final Metadata metadata = new Metadata();
 	private final BdfList list = BdfList.of("Sign this!", getRandomBytes(42));
 	private final String label = StringUtils.getRandomString(5);
+	private final Author author = getAuthor();
 
-	public ClientHelperImplTest() {
-		clientHelper =
-				new ClientHelperImpl(db, messageFactory, bdfReaderFactory,
-						bdfWriterFactory, metadataParser, metadataEncoder,
-						cryptoComponent);
-	}
+	private final ClientHelper clientHelper = new ClientHelperImpl(db,
+			messageFactory, bdfReaderFactory, bdfWriterFactory, metadataParser,
+			metadataEncoder, cryptoComponent, authorFactory);
 
 	@Test
 	public void testAddLocalMessage() throws Exception {
-		boolean shared = true;
+		boolean shared = new Random().nextBoolean();
 		Transaction txn = new Transaction(null, false);
 
 		context.checking(new Expectations() {{
@@ -180,8 +186,7 @@ public class ClientHelperImplTest extends BrambleTestCase {
 			oneOf(db).endTransaction(txn);
 		}});
 
-		assertEquals(map,
-				clientHelper.getMessageMetadataAsDictionary(groupId));
+		assertEquals(map, clientHelper.getMessageMetadataAsDictionary(groupId));
 		context.assertIsSatisfied();
 	}
 
@@ -318,8 +323,7 @@ public class ClientHelperImplTest extends BrambleTestCase {
 		}});
 
 		try {
-			clientHelper
-					.verifySignature(label, rawMessage, publicKey, list);
+			clientHelper.verifySignature(label, rawMessage, publicKey, list);
 			fail();
 		} catch (GeneralSecurityException e) {
 			// expected
@@ -327,6 +331,154 @@ public class ClientHelperImplTest extends BrambleTestCase {
 		}
 	}
 
+	@Test
+	public void testAcceptsValidAuthor() throws Exception {
+		BdfList authorList = BdfList.of(
+				author.getFormatVersion(),
+				author.getName(),
+				author.getPublicKey()
+		);
+
+		context.checking(new Expectations() {{
+			oneOf(authorFactory).createAuthor(author.getFormatVersion(),
+					author.getName(), author.getPublicKey());
+			will(returnValue(author));
+		}});
+
+		assertEquals(author, clientHelper.parseAndValidateAuthor(authorList));
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsTooShortAuthor() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				author.getName()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsTooLongAuthor() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				author.getName(),
+				author.getPublicKey(),
+				"foo"
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithNullFormatVersion() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				null,
+				author.getName(),
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithNonIntegerFormatVersion()
+			throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				"foo",
+				author.getName(),
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithUnknownFormatVersion() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion() + 1,
+				author.getName(),
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithTooShortName() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				"",
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithTooLongName() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				getRandomString(MAX_AUTHOR_NAME_LENGTH + 1),
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithNullName() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				null,
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithNonStringName() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				getRandomBytes(5),
+				author.getPublicKey()
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithTooShortPublicKey() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				author.getName(),
+				new byte[0]
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithTooLongPublicKey() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				author.getName(),
+				getRandomBytes(MAX_PUBLIC_KEY_LENGTH + 1)
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithNullPublicKey() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				author.getName(),
+				null
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
+	@Test(expected = FormatException.class)
+	public void testRejectsAuthorWithNonRawPublicKey() throws Exception {
+		BdfList invalidAuthor = BdfList.of(
+				author.getFormatVersion(),
+				author.getName(),
+				"foo"
+		);
+		clientHelper.parseAndValidateAuthor(invalidAuthor);
+	}
+
 	private byte[] expectToByteArray(BdfList list) throws Exception {
 		BdfWriter bdfWriter = context.mock(BdfWriter.class);
 
@@ -352,5 +504,4 @@ public class ClientHelperImplTest extends BrambleTestCase {
 			will(returnValue(eof));
 		}});
 	}
-
 }

bramble-core/src/test/java/org/briarproject/bramble/contact/ContactManagerImplTest.java

@@ -18,8 +18,9 @@ import org.junit.Test;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Random;
 
-import static org.briarproject.bramble.test.TestUtils.getRandomBytes;
+import static org.briarproject.bramble.test.TestUtils.getAuthor;
 import static org.briarproject.bramble.test.TestUtils.getRandomId;
 import static org.briarproject.bramble.test.TestUtils.getSecretKey;
 import static org.junit.Assert.assertEquals;
@@ -32,9 +33,7 @@ public class ContactManagerImplTest extends BrambleMockTestCase {
 	private final KeyManager keyManager = context.mock(KeyManager.class);
 	private final ContactManager contactManager;
 	private final ContactId contactId = new ContactId(42);
-	private final Author remote =
-			new Author(new AuthorId(getRandomId()), "remote",
-					getRandomBytes(42));
+	private final Author remote = getAuthor();
 	private final AuthorId local = new AuthorId(getRandomId());
 	private final boolean verified = false, active = true;
 	private final Contact contact =
@@ -47,8 +46,8 @@ public class ContactManagerImplTest extends BrambleMockTestCase {
 	@Test
 	public void testAddContact() throws Exception {
 		SecretKey master = getSecretKey();
-		long timestamp = 42;
-		boolean alice = true;
+		long timestamp = System.currentTimeMillis();
+		boolean alice = new Random().nextBoolean();
 		Transaction txn = new Transaction(null, false);
 
 		context.checking(new Expectations() {{

bramble-core/src/test/java/org/briarproject/bramble/db/DatabaseComponentImplTest.java

@@ -17,7 +17,6 @@ import org.briarproject.bramble.api.db.NoSuchTransportException;
 import org.briarproject.bramble.api.db.Transaction;
 import org.briarproject.bramble.api.event.EventBus;
 import org.briarproject.bramble.api.identity.Author;
-import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.identity.event.LocalAuthorAddedEvent;
 import org.briarproject.bramble.api.identity.event.LocalAuthorRemovedEvent;
@@ -49,7 +48,6 @@ import org.briarproject.bramble.api.transport.OutgoingKeys;
 import org.briarproject.bramble.api.transport.TransportKeys;
 import org.briarproject.bramble.test.BrambleMockTestCase;
 import org.briarproject.bramble.test.TestUtils;
-import org.briarproject.bramble.util.StringUtils;
 import org.jmock.Expectations;
 import org.junit.Test;
 
@@ -59,7 +57,6 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Map;
 
-import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_PUBLIC_KEY_LENGTH;
 import static org.briarproject.bramble.api.sync.Group.Visibility.INVISIBLE;
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
 import static org.briarproject.bramble.api.sync.Group.Visibility.VISIBLE;
@@ -68,6 +65,9 @@ import static org.briarproject.bramble.api.sync.ValidationManager.State.DELIVERE
 import static org.briarproject.bramble.api.sync.ValidationManager.State.UNKNOWN;
 import static org.briarproject.bramble.api.transport.TransportConstants.REORDERING_WINDOW_SIZE;
 import static org.briarproject.bramble.db.DatabaseConstants.MAX_OFFERED_MESSAGES;
+import static org.briarproject.bramble.test.TestUtils.getAuthor;
+import static org.briarproject.bramble.test.TestUtils.getLocalAuthor;
+import static org.briarproject.bramble.util.StringUtils.getRandomString;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -85,9 +85,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 	private final ClientId clientId;
 	private final GroupId groupId;
 	private final Group group;
-	private final AuthorId authorId;
 	private final Author author;
-	private final AuthorId localAuthorId;
 	private final LocalAuthor localAuthor;
 	private final MessageId messageId, messageId1;
 	private final int size;
@@ -100,18 +98,15 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 	private final Contact contact;
 
 	public DatabaseComponentImplTest() {
-		clientId = new ClientId(StringUtils.getRandomString(5));
+		clientId = new ClientId(getRandomString(123));
 		groupId = new GroupId(TestUtils.getRandomId());
 		byte[] descriptor = new byte[MAX_GROUP_DESCRIPTOR_LENGTH];
 		group = new Group(groupId, clientId, descriptor);
-		authorId = new AuthorId(TestUtils.getRandomId());
-		author = new Author(authorId, "Alice", new byte[MAX_PUBLIC_KEY_LENGTH]);
-		localAuthorId = new AuthorId(TestUtils.getRandomId());
-		long timestamp = System.currentTimeMillis();
-		localAuthor = new LocalAuthor(localAuthorId, "Bob",
-				new byte[MAX_PUBLIC_KEY_LENGTH], new byte[123], timestamp);
+		author = getAuthor();
+		localAuthor = getLocalAuthor();
 		messageId = new MessageId(TestUtils.getRandomId());
 		messageId1 = new MessageId(TestUtils.getRandomId());
+		long timestamp = System.currentTimeMillis();
 		size = 1234;
 		raw = new byte[size];
 		message = new Message(messageId, groupId, timestamp, raw);
@@ -120,7 +115,8 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 		transportId = new TransportId("id");
 		maxLatency = Integer.MAX_VALUE;
 		contactId = new ContactId(234);
-		contact = new Contact(contactId, author, localAuthorId, true, true);
+		contact = new Contact(contactId, author, localAuthor.getId(),
+				true, true);
 	}
 
 	private DatabaseComponent createDatabaseComponent(Database<Object> database,
@@ -142,18 +138,20 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 			oneOf(database).startTransaction();
 			will(returnValue(txn));
 			// registerLocalAuthor()
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(false));
 			oneOf(database).addLocalAuthor(txn, localAuthor);
 			oneOf(eventBus).broadcast(with(any(LocalAuthorAddedEvent.class)));
 			// addContact()
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(true));
-			oneOf(database).containsLocalAuthor(txn, authorId);
+			oneOf(database).containsLocalAuthor(txn, author.getId());
 			will(returnValue(false));
-			oneOf(database).containsContact(txn, authorId, localAuthorId);
+			oneOf(database).containsContact(txn, author.getId(),
+					localAuthor.getId());
 			will(returnValue(false));
-			oneOf(database).addContact(txn, author, localAuthorId, true, true);
+			oneOf(database).addContact(txn, author, localAuthor.getId(),
+					true, true);
 			will(returnValue(contactId));
 			oneOf(eventBus).broadcast(with(any(ContactAddedEvent.class)));
 			oneOf(eventBus).broadcast(with(any(
@@ -187,9 +185,9 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 			oneOf(database).removeContact(txn, contactId);
 			oneOf(eventBus).broadcast(with(any(ContactRemovedEvent.class)));
 			// removeLocalAuthor()
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(true));
-			oneOf(database).removeLocalAuthor(txn, localAuthorId);
+			oneOf(database).removeLocalAuthor(txn, localAuthor.getId());
 			oneOf(eventBus).broadcast(with(any(LocalAuthorRemovedEvent.class)));
 			// endTransaction()
 			oneOf(database).commitTransaction(txn);
@@ -203,9 +201,8 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 		Transaction transaction = db.startTransaction(false);
 		try {
 			db.addLocalAuthor(transaction, localAuthor);
-			assertEquals(contactId,
-					db.addContact(transaction, author, localAuthorId, true,
-							true));
+			assertEquals(contactId, db.addContact(transaction, author,
+					localAuthor.getId(), true, true));
 			assertEquals(Collections.singletonList(contact),
 					db.getContacts(transaction));
 			db.addGroup(transaction, group); // First time - listeners called
@@ -214,7 +211,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 					db.getGroups(transaction, clientId));
 			db.removeGroup(transaction, group);
 			db.removeContact(transaction, contactId);
-			db.removeLocalAuthor(transaction, localAuthorId);
+			db.removeLocalAuthor(transaction, localAuthor.getId());
 			db.commitTransaction(transaction);
 		} finally {
 			db.endTransaction(transaction);
@@ -487,7 +484,8 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 			// Check whether the pseudonym is in the DB (which it's not)
 			exactly(3).of(database).startTransaction();
 			will(returnValue(txn));
-			exactly(3).of(database).containsLocalAuthor(txn, localAuthorId);
+			exactly(3).of(database).containsLocalAuthor(txn,
+					localAuthor.getId());
 			will(returnValue(false));
 			exactly(3).of(database).abortTransaction(txn);
 		}});
@@ -496,7 +494,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 
 		Transaction transaction = db.startTransaction(false);
 		try {
-			db.addContact(transaction, author, localAuthorId, true, true);
+			db.addContact(transaction, author, localAuthor.getId(), true, true);
 			fail();
 		} catch (NoSuchLocalAuthorException expected) {
 			// Expected
@@ -506,7 +504,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 
 		transaction = db.startTransaction(false);
 		try {
-			db.getLocalAuthor(transaction, localAuthorId);
+			db.getLocalAuthor(transaction, localAuthor.getId());
 			fail();
 		} catch (NoSuchLocalAuthorException expected) {
 			// Expected
@@ -516,7 +514,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 
 		transaction = db.startTransaction(false);
 		try {
-			db.removeLocalAuthor(transaction, localAuthorId);
+			db.removeLocalAuthor(transaction, localAuthor.getId());
 			fail();
 		} catch (NoSuchLocalAuthorException expected) {
 			// Expected
@@ -759,18 +757,20 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 			oneOf(database).startTransaction();
 			will(returnValue(txn));
 			// registerLocalAuthor()
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(false));
 			oneOf(database).addLocalAuthor(txn, localAuthor);
 			oneOf(eventBus).broadcast(with(any(LocalAuthorAddedEvent.class)));
 			// addContact()
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(true));
-			oneOf(database).containsLocalAuthor(txn, authorId);
+			oneOf(database).containsLocalAuthor(txn, author.getId());
 			will(returnValue(false));
-			oneOf(database).containsContact(txn, authorId, localAuthorId);
+			oneOf(database).containsContact(txn, author.getId(),
+					localAuthor.getId());
 			will(returnValue(false));
-			oneOf(database).addContact(txn, author, localAuthorId, true, true);
+			oneOf(database).addContact(txn, author, localAuthor.getId(),
+					true, true);
 			will(returnValue(contactId));
 			oneOf(eventBus).broadcast(with(any(ContactAddedEvent.class)));
 			oneOf(eventBus).broadcast(with(any(
@@ -792,9 +792,8 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 		Transaction transaction = db.startTransaction(false);
 		try {
 			db.addLocalAuthor(transaction, localAuthor);
-			assertEquals(contactId,
-					db.addContact(transaction, author, localAuthorId, true,
-							true));
+			assertEquals(contactId, db.addContact(transaction, author,
+					localAuthor.getId(), true, true));
 			db.commitTransaction(transaction);
 		} finally {
 			db.endTransaction(transaction);
@@ -1406,10 +1405,10 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 		context.checking(new Expectations() {{
 			oneOf(database).startTransaction();
 			will(returnValue(txn));
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(true));
 			// Contact is a local identity
-			oneOf(database).containsLocalAuthor(txn, authorId);
+			oneOf(database).containsLocalAuthor(txn, author.getId());
 			will(returnValue(true));
 			oneOf(database).abortTransaction(txn);
 		}});
@@ -1419,7 +1418,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 
 		Transaction transaction = db.startTransaction(false);
 		try {
-			db.addContact(transaction, author, localAuthorId, true, true);
+			db.addContact(transaction, author, localAuthor.getId(), true, true);
 			fail();
 		} catch (ContactExistsException expected) {
 			// Expected
@@ -1433,12 +1432,13 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 		context.checking(new Expectations() {{
 			oneOf(database).startTransaction();
 			will(returnValue(txn));
-			oneOf(database).containsLocalAuthor(txn, localAuthorId);
+			oneOf(database).containsLocalAuthor(txn, localAuthor.getId());
 			will(returnValue(true));
-			oneOf(database).containsLocalAuthor(txn, authorId);
+			oneOf(database).containsLocalAuthor(txn, author.getId());
 			will(returnValue(false));
 			// Contact already exists for this local identity
-			oneOf(database).containsContact(txn, authorId, localAuthorId);
+			oneOf(database).containsContact(txn, author.getId(),
+					localAuthor.getId());
 			will(returnValue(true));
 			oneOf(database).abortTransaction(txn);
 		}});
@@ -1448,7 +1448,7 @@ public class DatabaseComponentImplTest extends BrambleMockTestCase {
 
 		Transaction transaction = db.startTransaction(false);
 		try {
-			db.addContact(transaction, author, localAuthorId, true, true);
+			db.addContact(transaction, author, localAuthor.getId(), true, true);
 			fail();
 		} catch (ContactExistsException expected) {
 			// Expected

bramble-core/src/test/java/org/briarproject/bramble/db/JdbcDatabaseTest.java

@@ -7,7 +7,6 @@ import org.briarproject.bramble.api.db.DatabaseConfig;
 import org.briarproject.bramble.api.db.DbException;
 import org.briarproject.bramble.api.db.Metadata;
 import org.briarproject.bramble.api.identity.Author;
-import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.settings.Settings;
@@ -26,7 +25,6 @@ import org.briarproject.bramble.system.SystemClock;
 import org.briarproject.bramble.test.BrambleTestCase;
 import org.briarproject.bramble.test.TestDatabaseConfig;
 import org.briarproject.bramble.test.TestUtils;
-import org.briarproject.bramble.util.StringUtils;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -46,7 +44,6 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
 import static java.util.concurrent.TimeUnit.SECONDS;
 import static org.briarproject.bramble.api.db.Metadata.REMOVE;
-import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_PUBLIC_KEY_LENGTH;
 import static org.briarproject.bramble.api.sync.Group.Visibility.INVISIBLE;
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
 import static org.briarproject.bramble.api.sync.Group.Visibility.VISIBLE;
@@ -56,6 +53,11 @@ import static org.briarproject.bramble.api.sync.ValidationManager.State.DELIVERE
 import static org.briarproject.bramble.api.sync.ValidationManager.State.INVALID;
 import static org.briarproject.bramble.api.sync.ValidationManager.State.PENDING;
 import static org.briarproject.bramble.api.sync.ValidationManager.State.UNKNOWN;
+import static org.briarproject.bramble.test.TestUtils.getAuthor;
+import static org.briarproject.bramble.test.TestUtils.getLocalAuthor;
+import static org.briarproject.bramble.test.TestUtils.getRandomBytes;
+import static org.briarproject.bramble.test.TestUtils.getRandomId;
+import static org.briarproject.bramble.util.StringUtils.getRandomString;
 import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -75,7 +77,6 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 	private final ClientId clientId;
 	private final Group group;
 	private final Author author;
-	private final AuthorId localAuthorId;
 	private final LocalAuthor localAuthor;
 	private final MessageId messageId;
 	private final long timestamp;
@@ -86,19 +87,16 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 	private final ContactId contactId;
 
 	JdbcDatabaseTest() throws Exception {
-		groupId = new GroupId(TestUtils.getRandomId());
-		clientId = new ClientId(StringUtils.getRandomString(5));
+		groupId = new GroupId(getRandomId());
+		clientId = new ClientId(getRandomString(123));
 		byte[] descriptor = new byte[MAX_GROUP_DESCRIPTOR_LENGTH];
 		group = new Group(groupId, clientId, descriptor);
-		AuthorId authorId = new AuthorId(TestUtils.getRandomId());
-		author = new Author(authorId, "Alice", new byte[MAX_PUBLIC_KEY_LENGTH]);
-		localAuthorId = new AuthorId(TestUtils.getRandomId());
+		author = getAuthor();
+		localAuthor = getLocalAuthor();
+		messageId = new MessageId(getRandomId());
 		timestamp = System.currentTimeMillis();
-		localAuthor = new LocalAuthor(localAuthorId, "Bob",
-				new byte[MAX_PUBLIC_KEY_LENGTH], new byte[123], timestamp);
-		messageId = new MessageId(TestUtils.getRandomId());
 		size = 1234;
-		raw = TestUtils.getRandomBytes(size);
+		raw = getRandomBytes(size);
 		message = new Message(messageId, groupId, timestamp, raw);
 		transportId = new TransportId("id");
 		contactId = new ContactId(1);
@@ -119,7 +117,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 		Connection txn = db.startTransaction();
 		assertFalse(db.containsContact(txn, contactId));
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		assertTrue(db.containsContact(txn, contactId));
 		assertFalse(db.containsGroup(txn, groupId));
@@ -182,7 +180,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and a shared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -220,7 +218,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and a shared but unvalidated message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -266,7 +264,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, an invisible group and a shared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addMessage(txn, message, DELIVERED, true);
@@ -318,7 +316,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and an unshared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -350,7 +348,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and a shared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -377,13 +375,13 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact and a visible group
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, false);
 
 		// Add some messages to ack
-		MessageId messageId1 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId1 = new MessageId(getRandomId());
 		Message message1 = new Message(messageId1, groupId, timestamp, raw);
 		db.addMessage(txn, message, DELIVERED, true);
 		db.addStatus(txn, contactId, messageId, false, true);
@@ -414,7 +412,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and a shared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -572,7 +570,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact and a shared group
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -592,7 +590,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 
 		// The group is not in the database
@@ -610,7 +608,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a group and a message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addMessage(txn, message, DELIVERED, true);
@@ -630,7 +628,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact and a group
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 
@@ -680,7 +678,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add the contact, the transport and the transport keys
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addTransport(txn, transportId, 123);
 		db.addTransportKeys(txn, contactId, keys);
@@ -742,7 +740,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add the contact, transport and transport keys
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addTransport(txn, transportId, 123);
 		db.updateTransportKeys(txn, Collections.singletonMap(contactId, keys));
@@ -778,7 +776,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add the contact, transport and transport keys
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addTransport(txn, transportId, 123);
 		db.updateTransportKeys(txn, Collections.singletonMap(contactId, keys));
@@ -813,7 +811,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 		db.addLocalAuthor(txn, localAuthor);
 
 		// Add a contact associated with the local author
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 
 		// Ensure contact is returned from database by Author ID
@@ -838,18 +836,19 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a local author - no contacts should be associated
 		db.addLocalAuthor(txn, localAuthor);
-		Collection<ContactId> contacts = db.getContacts(txn, localAuthorId);
+		Collection<ContactId> contacts =
+				db.getContacts(txn, localAuthor.getId());
 		assertEquals(Collections.emptyList(), contacts);
 
 		// Add a contact associated with the local author
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
-		contacts = db.getContacts(txn, localAuthorId);
+		contacts = db.getContacts(txn, localAuthor.getId());
 		assertEquals(Collections.singletonList(contactId), contacts);
 
 		// Remove the local author - the contact should be removed
-		db.removeLocalAuthor(txn, localAuthorId);
-		contacts = db.getContacts(txn, localAuthorId);
+		db.removeLocalAuthor(txn, localAuthor.getId());
+		contacts = db.getContacts(txn, localAuthor.getId());
 		assertEquals(Collections.emptyList(), contacts);
 		assertFalse(db.containsContact(txn, contactId));
 
@@ -864,14 +863,14 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact - initially there should be no offered messages
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		assertEquals(0, db.countOfferedMessages(txn, contactId));
 
 		// Add some offered messages and count them
 		List<MessageId> ids = new ArrayList<>();
 		for (int i = 0; i < 10; i++) {
-			MessageId m = new MessageId(TestUtils.getRandomId());
+			MessageId m = new MessageId(getRandomId());
 			db.addOfferedMessage(txn, contactId, m);
 			ids.add(m);
 		}
@@ -1056,7 +1055,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 	@Test
 	public void testMetadataQueries() throws Exception {
-		MessageId messageId1 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId1 = new MessageId(getRandomId());
 		Message message1 = new Message(messageId1, groupId, timestamp, raw);
 
 		Database<Connection> db = open(false);
@@ -1160,7 +1159,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 	@Test
 	public void testMetadataQueriesOnlyForDeliveredMessages() throws Exception {
-		MessageId messageId1 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId1 = new MessageId(getRandomId());
 		Message message1 = new Message(messageId1, groupId, timestamp, raw);
 
 		Database<Connection> db = open(false);
@@ -1231,10 +1230,10 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 	@Test
 	public void testMessageDependencies() throws Exception {
-		MessageId messageId1 = new MessageId(TestUtils.getRandomId());
-		MessageId messageId2 = new MessageId(TestUtils.getRandomId());
-		MessageId messageId3 = new MessageId(TestUtils.getRandomId());
-		MessageId messageId4 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId1 = new MessageId(getRandomId());
+		MessageId messageId2 = new MessageId(getRandomId());
+		MessageId messageId3 = new MessageId(getRandomId());
+		MessageId messageId4 = new MessageId(getRandomId());
 		Message message1 = new Message(messageId1, groupId, timestamp, raw);
 		Message message2 = new Message(messageId2, groupId, timestamp, raw);
 
@@ -1315,21 +1314,21 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 		db.addMessage(txn, message, PENDING, true);
 
 		// Add a second group
-		GroupId groupId1 = new GroupId(TestUtils.getRandomId());
+		GroupId groupId1 = new GroupId(getRandomId());
 		Group group1 = new Group(groupId1, clientId,
-				TestUtils.getRandomBytes(MAX_GROUP_DESCRIPTOR_LENGTH));
+				getRandomBytes(MAX_GROUP_DESCRIPTOR_LENGTH));
 		db.addGroup(txn, group1);
 
 		// Add a message to the second group
-		MessageId messageId1 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId1 = new MessageId(getRandomId());
 		Message message1 = new Message(messageId1, groupId1, timestamp, raw);
 		db.addMessage(txn, message1, DELIVERED, true);
 
 		// Create an ID for a missing message
-		MessageId messageId2 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId2 = new MessageId(getRandomId());
 
 		// Add another message to the first group
-		MessageId messageId3 = new MessageId(TestUtils.getRandomId());
+		MessageId messageId3 = new MessageId(getRandomId());
 		Message message3 = new Message(messageId3, groupId, timestamp, raw);
 		db.addMessage(txn, message3, DELIVERED, true);
 
@@ -1364,10 +1363,10 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 	@Test
 	public void testGetPendingMessagesForDelivery() throws Exception {
-		MessageId mId1 = new MessageId(TestUtils.getRandomId());
-		MessageId mId2 = new MessageId(TestUtils.getRandomId());
-		MessageId mId3 = new MessageId(TestUtils.getRandomId());
-		MessageId mId4 = new MessageId(TestUtils.getRandomId());
+		MessageId mId1 = new MessageId(getRandomId());
+		MessageId mId2 = new MessageId(getRandomId());
+		MessageId mId3 = new MessageId(getRandomId());
+		MessageId mId4 = new MessageId(getRandomId());
 		Message m1 = new Message(mId1, groupId, timestamp, raw);
 		Message m2 = new Message(mId2, groupId, timestamp, raw);
 		Message m3 = new Message(mId3, groupId, timestamp, raw);
@@ -1401,10 +1400,10 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 	@Test
 	public void testGetMessagesToShare() throws Exception {
-		MessageId mId1 = new MessageId(TestUtils.getRandomId());
-		MessageId mId2 = new MessageId(TestUtils.getRandomId());
-		MessageId mId3 = new MessageId(TestUtils.getRandomId());
-		MessageId mId4 = new MessageId(TestUtils.getRandomId());
+		MessageId mId1 = new MessageId(getRandomId());
+		MessageId mId2 = new MessageId(getRandomId());
+		MessageId mId3 = new MessageId(getRandomId());
+		MessageId mId4 = new MessageId(getRandomId());
 		Message m1 = new Message(mId1, groupId, timestamp, raw);
 		Message m2 = new Message(mId2, groupId, timestamp, raw);
 		Message m3 = new Message(mId3, groupId, timestamp, raw);
@@ -1443,7 +1442,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and a shared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -1512,9 +1511,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 	@Test
 	public void testDifferentLocalAuthorsCanHaveTheSameContact()
 			throws Exception {
-		AuthorId localAuthorId1 = new AuthorId(TestUtils.getRandomId());
-		LocalAuthor localAuthor1 = new LocalAuthor(localAuthorId1, "Carol",
-				new byte[MAX_PUBLIC_KEY_LENGTH], new byte[123], timestamp);
+		LocalAuthor localAuthor1 = getLocalAuthor();
 
 		Database<Connection> db = open(false);
 		Connection txn = db.startTransaction();
@@ -1525,15 +1522,15 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add the same contact for each local author
 		ContactId contactId =
-				db.addContact(txn, author, localAuthorId, true, true);
+				db.addContact(txn, author, localAuthor.getId(), true, true);
 		ContactId contactId1 =
-				db.addContact(txn, author, localAuthorId1, true, true);
+				db.addContact(txn, author, localAuthor1.getId(), true, true);
 
 		// The contacts should be distinct
 		assertNotEquals(contactId, contactId1);
 		assertEquals(2, db.getContacts(txn).size());
-		assertEquals(1, db.getContacts(txn, localAuthorId).size());
-		assertEquals(1, db.getContacts(txn, localAuthorId1).size());
+		assertEquals(1, db.getContacts(txn, localAuthor.getId()).size());
+		assertEquals(1, db.getContacts(txn, localAuthor1.getId()).size());
 
 		db.commitTransaction(txn);
 		db.close();
@@ -1546,7 +1543,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact, a shared group and a shared message
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 		db.addGroup(txn, group);
 		db.addGroupVisibility(txn, contactId, groupId, true);
@@ -1592,7 +1589,7 @@ public abstract class JdbcDatabaseTest extends BrambleTestCase {
 
 		// Add a contact
 		db.addLocalAuthor(txn, localAuthor);
-		assertEquals(contactId, db.addContact(txn, author, localAuthorId,
+		assertEquals(contactId, db.addContact(txn, author, localAuthor.getId(),
 				true, true));
 
 		// The contact should be active

bramble-core/src/test/java/org/briarproject/bramble/identity/IdentityManagerImplTest.java

@@ -10,8 +10,6 @@ import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.IdentityManager;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.test.BrambleMockTestCase;
-import org.briarproject.bramble.test.TestUtils;
-import org.briarproject.bramble.util.StringUtils;
 import org.jmock.Expectations;
 import org.junit.Test;
 
@@ -23,6 +21,8 @@ import static org.briarproject.bramble.api.identity.Author.Status.OURSELVES;
 import static org.briarproject.bramble.api.identity.Author.Status.UNKNOWN;
 import static org.briarproject.bramble.api.identity.Author.Status.UNVERIFIED;
 import static org.briarproject.bramble.api.identity.Author.Status.VERIFIED;
+import static org.briarproject.bramble.test.TestUtils.getAuthor;
+import static org.briarproject.bramble.test.TestUtils.getLocalAuthor;
 import static org.junit.Assert.assertEquals;
 
 public class IdentityManagerImplTest extends BrambleMockTestCase {
@@ -30,11 +30,7 @@ public class IdentityManagerImplTest extends BrambleMockTestCase {
 	private final IdentityManager identityManager;
 	private final DatabaseComponent db = context.mock(DatabaseComponent.class);
 	private final Transaction txn = new Transaction(null, false);
-	private final LocalAuthor localAuthor =
-			new LocalAuthor(new AuthorId(TestUtils.getRandomId()),
-					StringUtils.getRandomString(8),
-					TestUtils.getRandomBytes(42), TestUtils.getRandomBytes(42),
-					0);
+	private final LocalAuthor localAuthor = getLocalAuthor();
 	private final Collection<LocalAuthor> localAuthors =
 			Collections.singletonList(localAuthor);
 
@@ -80,7 +76,8 @@ public class IdentityManagerImplTest extends BrambleMockTestCase {
 
 	@Test
 	public void testGetAuthorStatus() throws DbException {
-		AuthorId authorId = new AuthorId(TestUtils.getRandomId());
+		Author author = getAuthor();
+		AuthorId authorId = author.getId();
 		Collection<Contact> contacts = new ArrayList<>();
 
 		context.checking(new Expectations() {{
@@ -95,20 +92,16 @@ public class IdentityManagerImplTest extends BrambleMockTestCase {
 		assertEquals(UNKNOWN, identityManager.getAuthorStatus(authorId));
 
 		// add one unverified contact
-		Author author = new Author(authorId, StringUtils.getRandomString(8),
-				TestUtils.getRandomBytes(42));
-		Contact contact =
-				new Contact(new ContactId(1), author, localAuthor.getId(),
-						false, true);
+		Contact contact = new Contact(new ContactId(1), author,
+				localAuthor.getId(), false, true);
 		contacts.add(contact);
 
 		checkAuthorStatusContext(authorId, contacts);
 		assertEquals(UNVERIFIED, identityManager.getAuthorStatus(authorId));
 
 		// add one verified contact
-		Contact contact2 =
-				new Contact(new ContactId(1), author, localAuthor.getId(),
-						true, true);
+		Contact contact2 = new Contact(new ContactId(1), author,
+				localAuthor.getId(), true, true);
 		contacts.add(contact2);
 
 		checkAuthorStatusContext(authorId, contacts);

bramble-core/src/test/java/org/briarproject/bramble/properties/TransportPropertyManagerImplTest.java

@@ -11,8 +11,6 @@ import org.briarproject.bramble.api.data.MetadataParser;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.Metadata;
 import org.briarproject.bramble.api.db.Transaction;
-import org.briarproject.bramble.api.identity.Author;
-import org.briarproject.bramble.api.identity.AuthorId;
 import org.briarproject.bramble.api.identity.LocalAuthor;
 import org.briarproject.bramble.api.plugin.TransportId;
 import org.briarproject.bramble.api.properties.TransportProperties;
@@ -31,16 +29,15 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
-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.properties.TransportPropertyManager.CLIENT_ID;
 import static org.briarproject.bramble.api.properties.TransportPropertyManager.CLIENT_VERSION;
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
 import static org.briarproject.bramble.api.sync.SyncConstants.MAX_GROUP_DESCRIPTOR_LENGTH;
 import static org.briarproject.bramble.api.sync.SyncConstants.MAX_MESSAGE_BODY_LENGTH;
+import static org.briarproject.bramble.test.TestUtils.getAuthor;
+import static org.briarproject.bramble.test.TestUtils.getLocalAuthor;
 import static org.briarproject.bramble.test.TestUtils.getRandomBytes;
 import static org.briarproject.bramble.test.TestUtils.getRandomId;
-import static org.briarproject.bramble.util.StringUtils.getRandomString;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 
@@ -609,22 +606,10 @@ public class TransportPropertyManagerImplTest extends BrambleMockTestCase {
 		return new Group(g, CLIENT_ID, descriptor);
 	}
 
-	private LocalAuthor getLocalAuthor() {
-		AuthorId id = new AuthorId(getRandomId());
-		String name = getRandomString(MAX_AUTHOR_NAME_LENGTH);
-		byte[] publicKey = getRandomBytes(MAX_PUBLIC_KEY_LENGTH);
-		byte[] privateKey = getRandomBytes(MAX_PUBLIC_KEY_LENGTH);
-		long created = System.currentTimeMillis();
-		return new LocalAuthor(id, name, publicKey, privateKey, created);
-	}
-
 	private Contact getContact(boolean active) {
 		ContactId c = new ContactId(nextContactId++);
-		AuthorId a = new AuthorId(getRandomId());
-		String name = getRandomString(MAX_AUTHOR_NAME_LENGTH);
-		byte[] publicKey = getRandomBytes(MAX_PUBLIC_KEY_LENGTH);
-		return new Contact(c, new Author(a, name, publicKey),
-				localAuthor.getId(), true, active);
+		return new Contact(c, getAuthor(), localAuthor.getId(),
+				true, active);
 	}
 
 	private Message getMessage(GroupId g, long timestamp) {

bramble-core/src/test/java/org/briarproject/bramble/test/ValidatorTestCase.java

@@ -9,7 +9,10 @@ import org.briarproject.bramble.api.sync.GroupId;
 import org.briarproject.bramble.api.sync.Message;
 import org.briarproject.bramble.api.sync.MessageId;
 import org.briarproject.bramble.api.system.Clock;
-import org.briarproject.bramble.util.StringUtils;
+
+import static org.briarproject.bramble.test.TestUtils.getRandomBytes;
+import static org.briarproject.bramble.test.TestUtils.getRandomId;
+import static org.briarproject.bramble.util.StringUtils.getRandomString;
 
 public abstract class ValidatorTestCase extends BrambleMockTestCase {
 
@@ -21,16 +24,14 @@ public abstract class ValidatorTestCase extends BrambleMockTestCase {
 	protected final AuthorFactory authorFactory =
 			context.mock(AuthorFactory.class);
 
-	protected final MessageId messageId =
-			new MessageId(TestUtils.getRandomId());
-	protected final GroupId groupId = new GroupId(TestUtils.getRandomId());
+	protected final MessageId messageId = new MessageId(getRandomId());
+	protected final GroupId groupId = new GroupId(getRandomId());
 	protected final long timestamp = 1234567890 * 1000L;
-	protected final byte[] raw = TestUtils.getRandomBytes(123);
+	protected final byte[] raw = getRandomBytes(123);
 	protected final Message message =
 			new Message(messageId, groupId, timestamp, raw);
-	protected final ClientId clientId =
-			new ClientId(StringUtils.getRandomString(123));
-	protected final byte[] descriptor = TestUtils.getRandomBytes(123);
+	protected final ClientId clientId = new ClientId(getRandomString(123));
+	protected final byte[] descriptor = getRandomBytes(123);
 	protected final Group group = new Group(groupId, clientId, descriptor);
 
 }

bramble-core/src/test/java/org/briarproject/bramble/transport/KeyManagerImplTest.java

@@ -23,8 +23,10 @@ import org.junit.Test;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Random;
 
 import static org.briarproject.bramble.api.transport.TransportConstants.TAG_LENGTH;
+import static org.briarproject.bramble.test.TestUtils.getAuthor;
 import static org.briarproject.bramble.test.TestUtils.getRandomBytes;
 import static org.briarproject.bramble.test.TestUtils.getRandomId;
 import static org.briarproject.bramble.test.TestUtils.getSecretKey;
@@ -59,9 +61,7 @@ public class KeyManagerImplTest extends BrambleTestCase {
 	@Before
 	public void testStartService() throws Exception {
 		Transaction txn = new Transaction(null, false);
-		AuthorId remoteAuthorId = new AuthorId(getRandomId());
-		Author remoteAuthor = new Author(remoteAuthorId, "author",
-				getRandomBytes(42));
+		Author remoteAuthor = getAuthor();
 		AuthorId localAuthorId = new AuthorId(getRandomId());
 		Collection<Contact> contacts = new ArrayList<>();
 		contacts.add(new Contact(contactId, remoteAuthor, localAuthorId, true,
@@ -101,12 +101,12 @@ public class KeyManagerImplTest extends BrambleTestCase {
 	@Test
 	public void testAddContact() throws Exception {
 		SecretKey secretKey = getSecretKey();
-		long timestamp = 42L;
-		boolean alice =  true;
+		long timestamp = System.currentTimeMillis();
+		boolean alice = new Random().nextBoolean();
 
 		context.checking(new Expectations() {{
-			oneOf(transportKeyManager)
-					.addContact(txn, contactId, secretKey, timestamp, alice);
+			oneOf(transportKeyManager).addContact(txn, contactId, secretKey,
+					timestamp, alice);
 		}});
 
 		keyManager.addContact(txn, contactId, secretKey, timestamp, alice);
@@ -121,8 +121,8 @@ public class KeyManagerImplTest extends BrambleTestCase {
 
 	@Test
 	public void testGetStreamContextForUnknownTransport() throws Exception {
-		assertEquals(null, keyManager
-				.getStreamContext(contactId, unknownTransportId));
+		assertEquals(null,
+				keyManager.getStreamContext(contactId, unknownTransportId));
 	}
 
 	@Test