]> nmode's Git Repositories - signal-cli/blobdiff - src/main/java/org/asamk/signal/manager/Manager.java
Update libsignal
[signal-cli] / src / main / java / org / asamk / signal / manager / Manager.java
index 000455ac169740d0ec9ad6b9099030f3dc708b92..c4f32460d97692d75262be1d3cd08ba6450a5510 100644 (file)
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2015-2020 AsamK and contributors
+  Copyright (C) 2015-2021 AsamK and contributors
 
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
  */
 package org.asamk.signal.manager;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
-
+import org.asamk.signal.manager.groups.GroupId;
+import org.asamk.signal.manager.groups.GroupIdV1;
+import org.asamk.signal.manager.groups.GroupIdV2;
+import org.asamk.signal.manager.groups.GroupInviteLinkUrl;
+import org.asamk.signal.manager.groups.GroupNotFoundException;
+import org.asamk.signal.manager.groups.GroupUtils;
+import org.asamk.signal.manager.groups.NotAGroupMemberException;
 import org.asamk.signal.manager.helper.GroupHelper;
+import org.asamk.signal.manager.helper.PinHelper;
 import org.asamk.signal.manager.helper.ProfileHelper;
 import org.asamk.signal.manager.helper.UnidentifiedAccessHelper;
-import org.asamk.signal.storage.SignalAccount;
-import org.asamk.signal.storage.contacts.ContactInfo;
-import org.asamk.signal.storage.groups.GroupInfo;
-import org.asamk.signal.storage.groups.GroupInfoV1;
-import org.asamk.signal.storage.groups.GroupInfoV2;
-import org.asamk.signal.storage.profiles.SignalProfile;
-import org.asamk.signal.storage.profiles.SignalProfileEntry;
-import org.asamk.signal.storage.protocol.JsonIdentityKeyStore;
-import org.asamk.signal.storage.stickers.Sticker;
-import org.asamk.signal.util.IOUtils;
-import org.asamk.signal.util.Util;
+import org.asamk.signal.manager.storage.SignalAccount;
+import org.asamk.signal.manager.storage.contacts.ContactInfo;
+import org.asamk.signal.manager.storage.groups.GroupInfo;
+import org.asamk.signal.manager.storage.groups.GroupInfoV1;
+import org.asamk.signal.manager.storage.groups.GroupInfoV2;
+import org.asamk.signal.manager.storage.messageCache.CachedMessage;
+import org.asamk.signal.manager.storage.profiles.SignalProfile;
+import org.asamk.signal.manager.storage.profiles.SignalProfileEntry;
+import org.asamk.signal.manager.storage.protocol.IdentityInfo;
+import org.asamk.signal.manager.storage.stickers.Sticker;
+import org.asamk.signal.manager.util.AttachmentUtils;
+import org.asamk.signal.manager.util.IOUtils;
+import org.asamk.signal.manager.util.KeyUtils;
+import org.asamk.signal.manager.util.ProfileUtils;
+import org.asamk.signal.manager.util.StickerUtils;
+import org.asamk.signal.manager.util.Utils;
 import org.signal.libsignal.metadata.InvalidMetadataMessageException;
 import org.signal.libsignal.metadata.InvalidMetadataVersionException;
 import org.signal.libsignal.metadata.ProtocolDuplicateMessageException;
@@ -43,7 +54,10 @@ import org.signal.libsignal.metadata.ProtocolLegacyMessageException;
 import org.signal.libsignal.metadata.ProtocolNoSessionException;
 import org.signal.libsignal.metadata.ProtocolUntrustedIdentityException;
 import org.signal.libsignal.metadata.SelfSendException;
+import org.signal.libsignal.metadata.certificate.CertificateValidator;
+import org.signal.storageservice.protos.groups.GroupChange;
 import org.signal.storageservice.protos.groups.local.DecryptedGroup;
+import org.signal.storageservice.protos.groups.local.DecryptedGroupJoinInfo;
 import org.signal.storageservice.protos.groups.local.DecryptedMember;
 import org.signal.zkgroup.InvalidInputException;
 import org.signal.zkgroup.VerificationFailedException;
@@ -53,34 +67,32 @@ import org.signal.zkgroup.groups.GroupSecretParams;
 import org.signal.zkgroup.profiles.ClientZkProfileOperations;
 import org.signal.zkgroup.profiles.ProfileKey;
 import org.signal.zkgroup.profiles.ProfileKeyCredential;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.whispersystems.libsignal.IdentityKey;
 import org.whispersystems.libsignal.IdentityKeyPair;
 import org.whispersystems.libsignal.InvalidKeyException;
 import org.whispersystems.libsignal.InvalidMessageException;
 import org.whispersystems.libsignal.InvalidVersionException;
-import org.whispersystems.libsignal.ecc.Curve;
-import org.whispersystems.libsignal.ecc.ECKeyPair;
 import org.whispersystems.libsignal.ecc.ECPublicKey;
 import org.whispersystems.libsignal.state.PreKeyRecord;
 import org.whispersystems.libsignal.state.SignedPreKeyRecord;
-import org.whispersystems.libsignal.util.KeyHelper;
-import org.whispersystems.libsignal.util.Medium;
 import org.whispersystems.libsignal.util.Pair;
 import org.whispersystems.libsignal.util.guava.Optional;
+import org.whispersystems.signalservice.api.KeyBackupService;
 import org.whispersystems.signalservice.api.SignalServiceAccountManager;
 import org.whispersystems.signalservice.api.SignalServiceMessagePipe;
 import org.whispersystems.signalservice.api.SignalServiceMessageReceiver;
 import org.whispersystems.signalservice.api.SignalServiceMessageSender;
-import org.whispersystems.signalservice.api.crypto.InvalidCiphertextException;
-import org.whispersystems.signalservice.api.crypto.ProfileCipher;
 import org.whispersystems.signalservice.api.crypto.SignalServiceCipher;
 import org.whispersystems.signalservice.api.crypto.UnidentifiedAccessPair;
 import org.whispersystems.signalservice.api.crypto.UntrustedIdentityException;
 import org.whispersystems.signalservice.api.groupsv2.ClientZkOperations;
+import org.whispersystems.signalservice.api.groupsv2.GroupLinkNotActiveException;
 import org.whispersystems.signalservice.api.groupsv2.GroupsV2Api;
 import org.whispersystems.signalservice.api.groupsv2.GroupsV2AuthorizationString;
 import org.whispersystems.signalservice.api.groupsv2.GroupsV2Operations;
-import org.whispersystems.signalservice.api.groupsv2.InvalidGroupStateException;
+import org.whispersystems.signalservice.api.kbs.MasterKey;
 import org.whispersystems.signalservice.api.messages.SendMessageResult;
 import org.whispersystems.signalservice.api.messages.SignalServiceAttachment;
 import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentPointer;
@@ -93,7 +105,6 @@ import org.whispersystems.signalservice.api.messages.SignalServiceGroup;
 import org.whispersystems.signalservice.api.messages.SignalServiceGroupV2;
 import org.whispersystems.signalservice.api.messages.SignalServiceReceiptMessage;
 import org.whispersystems.signalservice.api.messages.SignalServiceStickerManifestUpload;
-import org.whispersystems.signalservice.api.messages.SignalServiceStickerManifestUpload.StickerInfo;
 import org.whispersystems.signalservice.api.messages.multidevice.BlockedListMessage;
 import org.whispersystems.signalservice.api.messages.multidevice.ContactsMessage;
 import org.whispersystems.signalservice.api.messages.multidevice.DeviceContact;
@@ -103,6 +114,7 @@ import org.whispersystems.signalservice.api.messages.multidevice.DeviceGroup;
 import org.whispersystems.signalservice.api.messages.multidevice.DeviceGroupsInputStream;
 import org.whispersystems.signalservice.api.messages.multidevice.DeviceGroupsOutputStream;
 import org.whispersystems.signalservice.api.messages.multidevice.DeviceInfo;
+import org.whispersystems.signalservice.api.messages.multidevice.KeysMessage;
 import org.whispersystems.signalservice.api.messages.multidevice.RequestMessage;
 import org.whispersystems.signalservice.api.messages.multidevice.SentTranscriptMessage;
 import org.whispersystems.signalservice.api.messages.multidevice.SignalServiceSyncMessage;
@@ -110,26 +122,28 @@ import org.whispersystems.signalservice.api.messages.multidevice.StickerPackOper
 import org.whispersystems.signalservice.api.messages.multidevice.VerifiedMessage;
 import org.whispersystems.signalservice.api.profiles.ProfileAndCredential;
 import org.whispersystems.signalservice.api.profiles.SignalServiceProfile;
-import org.whispersystems.signalservice.api.push.ContactTokenDetails;
 import org.whispersystems.signalservice.api.push.SignalServiceAddress;
 import org.whispersystems.signalservice.api.push.exceptions.MissingConfigurationException;
+import org.whispersystems.signalservice.api.storage.StorageKey;
 import org.whispersystems.signalservice.api.util.InvalidNumberException;
+import org.whispersystems.signalservice.api.util.PhoneNumberFormatter;
 import org.whispersystems.signalservice.api.util.SleepTimer;
 import org.whispersystems.signalservice.api.util.StreamDetails;
 import org.whispersystems.signalservice.api.util.UptimeSleepTimer;
 import org.whispersystems.signalservice.api.util.UuidUtil;
 import org.whispersystems.signalservice.internal.configuration.SignalServiceConfiguration;
+import org.whispersystems.signalservice.internal.contacts.crypto.Quote;
+import org.whispersystems.signalservice.internal.contacts.crypto.UnauthenticatedQuoteException;
+import org.whispersystems.signalservice.internal.contacts.crypto.UnauthenticatedResponseException;
 import org.whispersystems.signalservice.internal.push.SignalServiceProtos;
 import org.whispersystems.signalservice.internal.push.UnsupportedDataMessageException;
-import org.whispersystems.signalservice.internal.push.VerifyAccountResponse;
 import org.whispersystems.signalservice.internal.util.DynamicCredentialsProvider;
 import org.whispersystems.signalservice.internal.util.Hex;
-import org.whispersystems.util.Base64;
+import org.whispersystems.signalservice.internal.util.Util;
 
 import java.io.Closeable;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -139,66 +153,90 @@ import java.net.URISyntaxException;
 import java.net.URLEncoder;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
-import java.nio.file.Paths;
-import java.nio.file.StandardCopyOption;
+import java.security.SignatureException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Locale;
-import java.util.Objects;
+import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 import java.util.stream.Collectors;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipFile;
 
+import static org.asamk.signal.manager.ServiceConfig.CDS_MRENCLAVE;
 import static org.asamk.signal.manager.ServiceConfig.capabilities;
+import static org.asamk.signal.manager.ServiceConfig.getIasKeyStore;
 
 public class Manager implements Closeable {
 
-    private final SleepTimer timer = new UptimeSleepTimer();
+    private final static Logger logger = LoggerFactory.getLogger(Manager.class);
+
+    private final CertificateValidator certificateValidator = new CertificateValidator(ServiceConfig.getUnidentifiedSenderTrustRoot());
 
     private final SignalServiceConfiguration serviceConfiguration;
     private final String userAgent;
-    private final boolean discoverableByPhoneNumber = true;
-    private final boolean unrestrictedUnidentifiedAccess = false;
 
-    private final SignalAccount account;
-    private final PathConfig pathConfig;
-    private SignalServiceAccountManager accountManager;
-    private GroupsV2Api groupsV2Api;
+    private SignalAccount account;
+    private final SignalServiceAccountManager accountManager;
+    private final GroupsV2Api groupsV2Api;
     private final GroupsV2Operations groupsV2Operations;
+    private final SignalServiceMessageReceiver messageReceiver;
+    private final ClientZkProfileOperations clientZkProfileOperations;
 
-    private SignalServiceMessageReceiver messageReceiver = null;
     private SignalServiceMessagePipe messagePipe = null;
     private SignalServiceMessagePipe unidentifiedMessagePipe = null;
 
     private final UnidentifiedAccessHelper unidentifiedAccessHelper;
     private final ProfileHelper profileHelper;
     private final GroupHelper groupHelper;
+    private final PinHelper pinHelper;
+    private final AvatarStore avatarStore;
+    private final AttachmentStore attachmentStore;
 
-    public Manager(
+    Manager(
             SignalAccount account,
             PathConfig pathConfig,
             SignalServiceConfiguration serviceConfiguration,
             String userAgent
     ) {
         this.account = account;
-        this.pathConfig = pathConfig;
         this.serviceConfiguration = serviceConfiguration;
         this.userAgent = userAgent;
         this.groupsV2Operations = capabilities.isGv2() ? new GroupsV2Operations(ClientZkOperations.create(
                 serviceConfiguration)) : null;
-        this.accountManager = createSignalServiceAccountManager();
+        final SleepTimer timer = new UptimeSleepTimer();
+        this.accountManager = new SignalServiceAccountManager(serviceConfiguration,
+                new DynamicCredentialsProvider(account.getUuid(),
+                        account.getUsername(),
+                        account.getPassword(),
+                        account.getSignalingKey(),
+                        account.getDeviceId()),
+                userAgent,
+                groupsV2Operations,
+                ServiceConfig.AUTOMATIC_NETWORK_RETRY,
+                timer);
         this.groupsV2Api = accountManager.getGroupsV2Api();
+        final KeyBackupService keyBackupService = ServiceConfig.createKeyBackupService(accountManager);
+        this.pinHelper = new PinHelper(keyBackupService);
+        this.clientZkProfileOperations = capabilities.isGv2() ? ClientZkOperations.create(serviceConfiguration)
+                .getProfileOperations() : null;
+        this.messageReceiver = new SignalServiceMessageReceiver(serviceConfiguration,
+                account.getUuid(),
+                account.getUsername(),
+                account.getPassword(),
+                account.getDeviceId(),
+                account.getSignalingKey(),
+                userAgent,
+                null,
+                timer,
+                clientZkProfileOperations,
+                ServiceConfig.AUTOMATIC_NETWORK_RETRY);
 
         this.account.setResolver(this::resolveSignalServiceAddress);
 
@@ -209,11 +247,15 @@ public class Manager implements Closeable {
         this.profileHelper = new ProfileHelper(account.getProfileStore()::getProfileKey,
                 unidentifiedAccessHelper::getAccessFor,
                 unidentified -> unidentified ? getOrCreateUnidentifiedMessagePipe() : getOrCreateMessagePipe(),
-                this::getOrCreateMessageReceiver);
+                () -> messageReceiver);
         this.groupHelper = new GroupHelper(this::getRecipientProfileKeyCredential,
                 this::getRecipientProfile,
                 account::getSelfAddress,
-                groupsV2Operations);
+                groupsV2Operations,
+                groupsV2Api,
+                this::getGroupAuthForToday);
+        this.avatarStore = new AvatarStore(pathConfig.getAvatarsPath());
+        this.attachmentStore = new AttachmentStore(pathConfig.getAttachmentsPath());
     }
 
     public String getUsername() {
@@ -224,18 +266,6 @@ public class Manager implements Closeable {
         return account.getSelfAddress();
     }
 
-    private SignalServiceAccountManager createSignalServiceAccountManager() {
-        return new SignalServiceAccountManager(serviceConfiguration,
-                new DynamicCredentialsProvider(account.getUuid(),
-                        account.getUsername(),
-                        account.getPassword(),
-                        null,
-                        account.getDeviceId()),
-                userAgent,
-                groupsV2Operations,
-                timer);
-    }
-
     private IdentityKeyPair getIdentityKeyPair() {
         return account.getSignalProtocolStore().getIdentityKeyPair();
     }
@@ -244,129 +274,113 @@ public class Manager implements Closeable {
         return account.getDeviceId();
     }
 
-    private String getMessageCachePath() {
-        return pathConfig.getDataPath() + "/" + account.getUsername() + ".d/msg-cache";
-    }
-
-    private String getMessageCachePath(String sender) {
-        if (sender == null || sender.isEmpty()) {
-            return getMessageCachePath();
-        }
-
-        return getMessageCachePath() + "/" + sender.replace("/", "_");
-    }
-
-    private File getMessageCacheFile(String sender, long now, long timestamp) throws IOException {
-        String cachePath = getMessageCachePath(sender);
-        IOUtils.createPrivateDirectories(cachePath);
-        return new File(cachePath + "/" + now + "_" + timestamp);
-    }
-
     public static Manager init(
-            String username, String settingsPath, SignalServiceConfiguration serviceConfiguration, String userAgent
-    ) throws IOException {
+            String username, File settingsPath, SignalServiceConfiguration serviceConfiguration, String userAgent
+    ) throws IOException, NotRegisteredException {
         PathConfig pathConfig = PathConfig.createDefault(settingsPath);
 
         if (!SignalAccount.userExists(pathConfig.getDataPath(), username)) {
-            IdentityKeyPair identityKey = KeyHelper.generateIdentityKeyPair();
-            int registrationId = KeyHelper.generateRegistrationId(false);
-
-            ProfileKey profileKey = KeyUtils.createProfileKey();
-            SignalAccount account = SignalAccount.create(pathConfig.getDataPath(),
-                    username,
-                    identityKey,
-                    registrationId,
-                    profileKey);
-            account.save();
-
-            return new Manager(account, pathConfig, serviceConfiguration, userAgent);
+            throw new NotRegisteredException();
         }
 
         SignalAccount account = SignalAccount.load(pathConfig.getDataPath(), username);
 
-        Manager m = new Manager(account, pathConfig, serviceConfiguration, userAgent);
-
-        m.migrateLegacyConfigs();
+        if (!account.isRegistered()) {
+            throw new NotRegisteredException();
+        }
 
-        return m;
+        return new Manager(account, pathConfig, serviceConfiguration, userAgent);
     }
 
-    private void migrateLegacyConfigs() {
-        if (account.getProfileKey() == null && isRegistered()) {
-            // Old config file, creating new profile key
-            account.setProfileKey(KeyUtils.createProfileKey());
-            account.save();
-        }
-        // Store profile keys only in profile store
-        for (ContactInfo contact : account.getContactStore().getContacts()) {
-            String profileKeyString = contact.profileKey;
-            if (profileKeyString == null) {
-                continue;
-            }
-            final ProfileKey profileKey;
-            try {
-                profileKey = new ProfileKey(Base64.decode(profileKeyString));
-            } catch (InvalidInputException | IOException e) {
-                continue;
-            }
-            contact.profileKey = null;
-            account.getProfileStore().storeProfileKey(contact.getAddress(), profileKey);
+    public static List<String> getAllLocalUsernames(File settingsPath) {
+        PathConfig pathConfig = PathConfig.createDefault(settingsPath);
+        final File dataPath = pathConfig.getDataPath();
+        final File[] files = dataPath.listFiles();
+
+        if (files == null) {
+            return List.of();
         }
+
+        return Arrays.stream(files)
+                .filter(File::isFile)
+                .map(File::getName)
+                .filter(file -> PhoneNumberFormatter.isValidNumber(file, null))
+                .collect(Collectors.toList());
     }
 
     public void checkAccountState() throws IOException {
-        if (account.isRegistered()) {
-            if (accountManager.getPreKeysCount() < ServiceConfig.PREKEY_MINIMUM_COUNT) {
-                refreshPreKeys();
-                account.save();
-            }
-            if (account.getUuid() == null) {
-                account.setUuid(accountManager.getOwnUuid());
-                account.save();
-            }
-            updateAccountAttributes();
+        if (accountManager.getPreKeysCount() < ServiceConfig.PREKEY_MINIMUM_COUNT) {
+            refreshPreKeys();
+            account.save();
         }
+        if (account.getUuid() == null) {
+            account.setUuid(accountManager.getOwnUuid());
+            account.save();
+        }
+        updateAccountAttributes();
     }
 
-    public boolean isRegistered() {
-        return account.isRegistered();
-    }
-
-    public void register(boolean voiceVerification, String captcha) throws IOException {
-        account.setPassword(KeyUtils.createPassword());
-
-        // Resetting UUID, because registering doesn't work otherwise
-        account.setUuid(null);
-        accountManager = createSignalServiceAccountManager();
-        this.groupsV2Api = accountManager.getGroupsV2Api();
+    /**
+     * This is used for checking a set of phone numbers for registration on Signal
+     *
+     * @param numbers The set of phone number in question
+     * @return A map of numbers to booleans. True if registered, false otherwise. Should never be null
+     * @throws IOException if its unable to get the contacts to check if they're registered
+     */
+    public Map<String, Boolean> areUsersRegistered(Set<String> numbers) throws IOException {
+        // Note "contactDetails" has no optionals. It only gives us info on users who are registered
+        Map<String, UUID> contactDetails = getRegisteredUsers(numbers);
 
-        if (voiceVerification) {
-            accountManager.requestVoiceVerificationCode(Locale.getDefault(),
-                    Optional.fromNullable(captcha),
-                    Optional.absent());
-        } else {
-            accountManager.requestSmsVerificationCode(false, Optional.fromNullable(captcha), Optional.absent());
-        }
+        Set<String> registeredUsers = contactDetails.keySet();
 
-        account.setRegistered(false);
-        account.save();
+        return numbers.stream().collect(Collectors.toMap(x -> x, registeredUsers::contains));
     }
 
     public void updateAccountAttributes() throws IOException {
         accountManager.setAccountAttributes(account.getSignalingKey(),
                 account.getSignalProtocolStore().getLocalRegistrationId(),
                 true,
-                account.getRegistrationLockPin(),
-                account.getRegistrationLock(),
-                unidentifiedAccessHelper.getSelfUnidentifiedAccessKey(),
-                unrestrictedUnidentifiedAccess,
+                // set legacy pin only if no KBS master key is set
+                account.getPinMasterKey() == null ? account.getRegistrationLockPin() : null,
+                account.getPinMasterKey() == null ? null : account.getPinMasterKey().deriveRegistrationLock(),
+                account.getSelfUnidentifiedAccessKey(),
+                account.isUnrestrictedUnidentifiedAccess(),
                 capabilities,
-                discoverableByPhoneNumber);
+                account.isDiscoverableByPhoneNumber());
     }
 
-    public void setProfile(String name, File avatar) throws IOException {
-        try (final StreamDetails streamDetails = avatar == null ? null : Utils.createStreamDetailsFromFile(avatar)) {
-            accountManager.setVersionedProfile(account.getUuid(), account.getProfileKey(), name, streamDetails);
+    /**
+     * @param avatar if avatar is null the image from the local avatar store is used (if present),
+     *               if it's Optional.absent(), the avatar will be removed
+     */
+    public void setProfile(String name, Optional<File> avatar) throws IOException {
+        // TODO
+        String about = null;
+        String aboutEmoji = null;
+
+        try (final StreamDetails streamDetails = avatar == null
+                ? avatarStore.retrieveProfileAvatar(getSelfAddress())
+                : avatar.isPresent() ? Utils.createStreamDetailsFromFile(avatar.get()) : null) {
+            accountManager.setVersionedProfile(account.getUuid(),
+                    account.getProfileKey(),
+                    name,
+                    about,
+                    aboutEmoji,
+                    streamDetails);
+        }
+
+        if (avatar != null) {
+            if (avatar.isPresent()) {
+                avatarStore.storeProfileAvatar(getSelfAddress(),
+                        outputStream -> IOUtils.copyFileToStream(avatar.get(), outputStream));
+            } else {
+                avatarStore.deleteProfileAvatar(getSelfAddress());
+            }
+        }
+
+        try {
+            sendSyncMessage(SignalServiceSyncMessage.forFetchLatest(SignalServiceSyncMessage.FetchType.LOCAL_PROFILE));
+        } catch (UntrustedIdentityException ignored) {
         }
     }
 
@@ -375,6 +389,7 @@ public class Manager implements Closeable {
         // If this is the master device, other users can't send messages to this number anymore.
         // If this is a linked device, other users can still send messages, but this device doesn't receive them anymore.
         accountManager.setGcmId(Optional.absent());
+        accountManager.deleteAccount();
 
         account.setRegistered(false);
         account.save();
@@ -395,7 +410,7 @@ public class Manager implements Closeable {
     }
 
     public void addDeviceLink(URI linkUri) throws IOException, InvalidKeyException {
-        Utils.DeviceLinkInfo info = Utils.parseDeviceLinkUri(linkUri);
+        DeviceLinkInfo info = DeviceLinkInfo.parseDeviceLinkUri(linkUri);
 
         addDevice(info.deviceIdentifier, info.deviceKey);
     }
@@ -413,80 +428,28 @@ public class Manager implements Closeable {
         account.save();
     }
 
-    private List<PreKeyRecord> generatePreKeys() {
-        List<PreKeyRecord> records = new ArrayList<>(ServiceConfig.PREKEY_BATCH_SIZE);
-
-        final int offset = account.getPreKeyIdOffset();
-        for (int i = 0; i < ServiceConfig.PREKEY_BATCH_SIZE; i++) {
-            int preKeyId = (offset + i) % Medium.MAX_VALUE;
-            ECKeyPair keyPair = Curve.generateKeyPair();
-            PreKeyRecord record = new PreKeyRecord(preKeyId, keyPair);
-
-            records.add(record);
-        }
-
-        account.addPreKeys(records);
-        account.save();
-
-        return records;
-    }
-
-    private SignedPreKeyRecord generateSignedPreKey(IdentityKeyPair identityKeyPair) {
-        try {
-            ECKeyPair keyPair = Curve.generateKeyPair();
-            byte[] signature = Curve.calculateSignature(identityKeyPair.getPrivateKey(),
-                    keyPair.getPublicKey().serialize());
-            SignedPreKeyRecord record = new SignedPreKeyRecord(account.getNextSignedPreKeyId(),
-                    System.currentTimeMillis(),
-                    keyPair,
-                    signature);
-
-            account.addSignedPreKey(record);
-            account.save();
-
-            return record;
-        } catch (InvalidKeyException e) {
-            throw new AssertionError(e);
+    public void setRegistrationLockPin(Optional<String> pin) throws IOException, UnauthenticatedResponseException {
+        if (!account.isMasterDevice()) {
+            throw new RuntimeException("Only master device can set a PIN");
         }
-    }
+        if (pin.isPresent()) {
+            final MasterKey masterKey = account.getPinMasterKey() != null
+                    ? account.getPinMasterKey()
+                    : KeyUtils.createMasterKey();
 
-    public void verifyAccount(String verificationCode, String pin) throws IOException {
-        verificationCode = verificationCode.replace("-", "");
-        account.setSignalingKey(KeyUtils.createSignalingKey());
-        // TODO make unrestricted unidentified access configurable
-        VerifyAccountResponse response = accountManager.verifyAccountWithCode(verificationCode,
-                account.getSignalingKey(),
-                account.getSignalProtocolStore().getLocalRegistrationId(),
-                true,
-                pin,
-                null,
-                unidentifiedAccessHelper.getSelfUnidentifiedAccessKey(),
-                unrestrictedUnidentifiedAccess,
-                capabilities,
-                discoverableByPhoneNumber);
-
-        UUID uuid = UuidUtil.parseOrNull(response.getUuid());
-        // TODO response.isStorageCapable()
-        //accountManager.setGcmId(Optional.of(GoogleCloudMessaging.getInstance(this).register(REGISTRATION_ID)));
-        account.setRegistered(true);
-        account.setUuid(uuid);
-        account.setRegistrationLockPin(pin);
-        account.getSignalProtocolStore()
-                .saveIdentity(account.getSelfAddress(),
-                        getIdentityKeyPair().getPublicKey(),
-                        TrustLevel.TRUSTED_VERIFIED);
-
-        refreshPreKeys();
-        account.save();
-    }
+            pinHelper.setRegistrationLockPin(pin.get(), masterKey);
 
-    public void setRegistrationLockPin(Optional<String> pin) throws IOException {
-        if (pin.isPresent()) {
             account.setRegistrationLockPin(pin.get());
-            throw new RuntimeException("Not implemented anymore, will be replaced with KBS");
+            account.setPinMasterKey(masterKey);
         } else {
-            account.setRegistrationLockPin(null);
+            // Remove legacy registration lock
             accountManager.removeRegistrationLockV1();
+
+            // Remove KBS Pin
+            pinHelper.removeRegistrationLockPin();
+
+            account.setRegistrationLockPin(null);
+            account.setPinMasterKey(null);
         }
         account.save();
     }
@@ -499,45 +462,41 @@ public class Manager implements Closeable {
         accountManager.setPreKeys(identityKeyPair.getPublicKey(), signedPreKeyRecord, oneTimePreKeys);
     }
 
-    private SignalServiceMessageReceiver createMessageReceiver() {
-        final ClientZkProfileOperations clientZkProfileOperations = capabilities.isGv2() ? ClientZkOperations.create(
-                serviceConfiguration).getProfileOperations() : null;
-        return new SignalServiceMessageReceiver(serviceConfiguration,
-                account.getUuid(),
-                account.getUsername(),
-                account.getPassword(),
-                account.getDeviceId(),
-                account.getSignalingKey(),
-                userAgent,
-                null,
-                timer,
-                clientZkProfileOperations);
+    private List<PreKeyRecord> generatePreKeys() {
+        final int offset = account.getPreKeyIdOffset();
+
+        List<PreKeyRecord> records = KeyUtils.generatePreKeyRecords(offset, ServiceConfig.PREKEY_BATCH_SIZE);
+        account.addPreKeys(records);
+        account.save();
+
+        return records;
     }
 
-    private SignalServiceMessageReceiver getOrCreateMessageReceiver() {
-        if (messageReceiver == null) {
-            messageReceiver = createMessageReceiver();
-        }
-        return messageReceiver;
+    private SignedPreKeyRecord generateSignedPreKey(IdentityKeyPair identityKeyPair) {
+        final int signedPreKeyId = account.getNextSignedPreKeyId();
+
+        SignedPreKeyRecord record = KeyUtils.generateSignedPreKeyRecord(identityKeyPair, signedPreKeyId);
+        account.addSignedPreKey(record);
+        account.save();
+
+        return record;
     }
 
     private SignalServiceMessagePipe getOrCreateMessagePipe() {
         if (messagePipe == null) {
-            messagePipe = getOrCreateMessageReceiver().createMessagePipe();
+            messagePipe = messageReceiver.createMessagePipe();
         }
         return messagePipe;
     }
 
     private SignalServiceMessagePipe getOrCreateUnidentifiedMessagePipe() {
         if (unidentifiedMessagePipe == null) {
-            unidentifiedMessagePipe = getOrCreateMessageReceiver().createUnidentifiedMessagePipe();
+            unidentifiedMessagePipe = messageReceiver.createUnidentifiedMessagePipe();
         }
         return unidentifiedMessagePipe;
     }
 
     private SignalServiceMessageSender createMessageSender() {
-        final ClientZkProfileOperations clientZkProfileOperations = capabilities.isGv2() ? ClientZkOperations.create(
-                serviceConfiguration).getProfileOperations() : null;
         final ExecutorService executor = null;
         return new SignalServiceMessageSender(serviceConfiguration,
                 account.getUuid(),
@@ -552,36 +511,44 @@ public class Manager implements Closeable {
                 Optional.absent(),
                 clientZkProfileOperations,
                 executor,
-                ServiceConfig.MAX_ENVELOPE_SIZE);
+                ServiceConfig.MAX_ENVELOPE_SIZE,
+                ServiceConfig.AUTOMATIC_NETWORK_RETRY);
     }
 
-    private SignalServiceProfile getEncryptedRecipientProfile(SignalServiceAddress address) throws IOException {
-        return profileHelper.retrieveProfileSync(address, SignalServiceProfile.RequestType.PROFILE).getProfile();
+    private SignalProfile getRecipientProfile(
+            SignalServiceAddress address
+    ) {
+        return getRecipientProfile(address, false);
     }
 
     private SignalProfile getRecipientProfile(
-            SignalServiceAddress address
+            SignalServiceAddress address, boolean force
     ) {
         SignalProfileEntry profileEntry = account.getProfileStore().getProfileEntry(address);
         if (profileEntry == null) {
             return null;
         }
         long now = new Date().getTime();
-        // Profiles are cache for 24h before retrieving them again
+        // Profiles are cached for 24h before retrieving them again
         if (!profileEntry.isRequestPending() && (
-                profileEntry.getProfile() == null || now - profileEntry.getLastUpdateTimestamp() > 24 * 60 * 60 * 1000
+                force
+                        || profileEntry.getProfile() == null
+                        || now - profileEntry.getLastUpdateTimestamp() > 24 * 60 * 60 * 1000
         )) {
-            ProfileKey profileKey = profileEntry.getProfileKey();
             profileEntry.setRequestPending(true);
-            SignalProfile profile;
+            final SignalServiceProfile encryptedProfile;
             try {
-                profile = retrieveRecipientProfile(address, profileKey);
+                encryptedProfile = profileHelper.retrieveProfileSync(address, SignalServiceProfile.RequestType.PROFILE)
+                        .getProfile();
             } catch (IOException e) {
-                System.err.println("Failed to retrieve profile, ignoring: " + e.getMessage());
-                profileEntry.setRequestPending(false);
+                logger.warn("Failed to retrieve profile, ignoring: {}", e.getMessage());
                 return null;
+            } finally {
+                profileEntry.setRequestPending(false);
             }
-            profileEntry.setRequestPending(false);
+
+            final ProfileKey profileKey = profileEntry.getProfileKey();
+            final SignalProfile profile = decryptProfileAndDownloadAvatar(address, profileKey, encryptedProfile);
             account.getProfileStore()
                     .updateProfile(address, profileKey, now, profile, profileEntry.getProfileKeyCredential());
             return profile;
@@ -600,13 +567,13 @@ public class Manager implements Closeable {
                 profileAndCredential = profileHelper.retrieveProfileSync(address,
                         SignalServiceProfile.RequestType.PROFILE_AND_CREDENTIAL);
             } catch (IOException e) {
-                System.err.println("Failed to retrieve profile key credential, ignoring: " + e.getMessage());
+                logger.warn("Failed to retrieve profile key credential, ignoring: {}", e.getMessage());
                 return null;
             }
 
             long now = new Date().getTime();
             final ProfileKeyCredential profileKeyCredential = profileAndCredential.getProfileKeyCredential().orNull();
-            final SignalProfile profile = decryptProfile(address,
+            final SignalProfile profile = decryptProfileAndDownloadAvatar(address,
                     profileEntry.getProfileKey(),
                     profileAndCredential.getProfile());
             account.getProfileStore()
@@ -616,76 +583,36 @@ public class Manager implements Closeable {
         return profileEntry.getProfileKeyCredential();
     }
 
-    private SignalProfile retrieveRecipientProfile(
-            SignalServiceAddress address, ProfileKey profileKey
-    ) throws IOException {
-        final SignalServiceProfile encryptedProfile = getEncryptedRecipientProfile(address);
-
-        return decryptProfile(address, profileKey, encryptedProfile);
-    }
-
-    private SignalProfile decryptProfile(
+    private SignalProfile decryptProfileAndDownloadAvatar(
             final SignalServiceAddress address, final ProfileKey profileKey, final SignalServiceProfile encryptedProfile
     ) {
-        File avatarFile = null;
-        try {
-            avatarFile = encryptedProfile.getAvatar() == null
-                    ? null
-                    : retrieveProfileAvatar(address, encryptedProfile.getAvatar(), profileKey);
-        } catch (Throwable e) {
-            System.err.println("Failed to retrieve profile avatar, ignoring: " + e.getMessage());
+        if (encryptedProfile.getAvatar() != null) {
+            downloadProfileAvatar(address, encryptedProfile.getAvatar(), profileKey);
         }
 
-        ProfileCipher profileCipher = new ProfileCipher(profileKey);
-        try {
-            String name;
-            try {
-                name = encryptedProfile.getName() == null
-                        ? null
-                        : new String(profileCipher.decryptName(Base64.decode(encryptedProfile.getName())));
-            } catch (IOException e) {
-                name = null;
-            }
-            String unidentifiedAccess;
-            try {
-                unidentifiedAccess = encryptedProfile.getUnidentifiedAccess() == null
-                        || !profileCipher.verifyUnidentifiedAccess(Base64.decode(encryptedProfile.getUnidentifiedAccess()))
-                        ? null
-                        : encryptedProfile.getUnidentifiedAccess();
-            } catch (IOException e) {
-                unidentifiedAccess = null;
-            }
-            return new SignalProfile(encryptedProfile.getIdentityKey(),
-                    name,
-                    avatarFile,
-                    unidentifiedAccess,
-                    encryptedProfile.isUnrestrictedUnidentifiedAccess(),
-                    encryptedProfile.getCapabilities());
-        } catch (InvalidCiphertextException e) {
-            return null;
-        }
+        return ProfileUtils.decryptProfile(profileKey, encryptedProfile);
     }
 
-    private Optional<SignalServiceAttachmentStream> createGroupAvatarAttachment(byte[] groupId) throws IOException {
-        File file = getGroupAvatarFile(groupId);
-        if (!file.exists()) {
+    private Optional<SignalServiceAttachmentStream> createGroupAvatarAttachment(GroupId groupId) throws IOException {
+        final StreamDetails streamDetails = avatarStore.retrieveGroupAvatar(groupId);
+        if (streamDetails == null) {
             return Optional.absent();
         }
 
-        return Optional.of(Utils.createAttachment(file));
+        return Optional.of(AttachmentUtils.createAttachment(streamDetails, Optional.absent()));
     }
 
-    private Optional<SignalServiceAttachmentStream> createContactAvatarAttachment(String number) throws IOException {
-        File file = getContactAvatarFile(number);
-        if (!file.exists()) {
+    private Optional<SignalServiceAttachmentStream> createContactAvatarAttachment(SignalServiceAddress address) throws IOException {
+        final StreamDetails streamDetails = avatarStore.retrieveContactAvatar(address);
+        if (streamDetails == null) {
             return Optional.absent();
         }
 
-        return Optional.of(Utils.createAttachment(file));
+        return Optional.of(AttachmentUtils.createAttachment(streamDetails, Optional.absent()));
     }
 
-    private GroupInfo getGroupForSending(byte[] groupId) throws GroupNotFoundException, NotAGroupMemberException {
-        GroupInfo g = account.getGroupStore().getGroup(groupId);
+    private GroupInfo getGroupForSending(GroupId groupId) throws GroupNotFoundException, NotAGroupMemberException {
+        GroupInfo g = getGroup(groupId);
         if (g == null) {
             throw new GroupNotFoundException(groupId);
         }
@@ -695,35 +622,35 @@ public class Manager implements Closeable {
         return g;
     }
 
-    public List<GroupInfo> getGroups() {
-        return account.getGroupStore().getGroups();
+    private GroupInfo getGroupForUpdating(GroupId groupId) throws GroupNotFoundException, NotAGroupMemberException {
+        GroupInfo g = getGroup(groupId);
+        if (g == null) {
+            throw new GroupNotFoundException(groupId);
+        }
+        if (!g.isMember(account.getSelfAddress()) && !g.isPendingMember(account.getSelfAddress())) {
+            throw new NotAGroupMemberException(groupId, g.getTitle());
+        }
+        return g;
     }
 
-    public Pair<Long, List<SendMessageResult>> sendGroupMessage(
-            SignalServiceDataMessage.Builder messageBuilder, byte[] groupId
-    ) throws IOException, GroupNotFoundException, NotAGroupMemberException {
-        final GroupInfo g = getGroupForSending(groupId);
-
-        GroupUtils.setGroupContext(messageBuilder, g);
-        messageBuilder.withExpiration(g.getMessageExpirationTime());
-
-        return sendMessage(messageBuilder, g.getMembersWithout(account.getSelfAddress()));
+    public List<GroupInfo> getGroups() {
+        return account.getGroupStore().getGroups();
     }
 
     public Pair<Long, List<SendMessageResult>> sendGroupMessage(
-            String messageText, List<String> attachments, byte[] groupId
+            String messageText, List<String> attachments, GroupId groupId
     ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException {
         final SignalServiceDataMessage.Builder messageBuilder = SignalServiceDataMessage.newBuilder()
                 .withBody(messageText);
         if (attachments != null) {
-            messageBuilder.withAttachments(Utils.getSignalServiceAttachments(attachments));
+            messageBuilder.withAttachments(AttachmentUtils.getSignalServiceAttachments(attachments));
         }
 
         return sendGroupMessage(messageBuilder, groupId);
     }
 
     public Pair<Long, List<SendMessageResult>> sendGroupMessageReaction(
-            String emoji, boolean remove, String targetAuthor, long targetSentTimestamp, byte[] groupId
+            String emoji, boolean remove, String targetAuthor, long targetSentTimestamp, GroupId groupId
     ) throws IOException, InvalidNumberException, NotAGroupMemberException, GroupNotFoundException {
         SignalServiceDataMessage.Reaction reaction = new SignalServiceDataMessage.Reaction(emoji,
                 remove,
@@ -735,95 +662,134 @@ public class Manager implements Closeable {
         return sendGroupMessage(messageBuilder, groupId);
     }
 
-    public Pair<Long, List<SendMessageResult>> sendQuitGroupMessage(byte[] groupId) throws GroupNotFoundException, IOException, NotAGroupMemberException {
-        SignalServiceGroup group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.QUIT).withId(groupId).build();
+    public Pair<Long, List<SendMessageResult>> sendGroupMessage(
+            SignalServiceDataMessage.Builder messageBuilder, GroupId groupId
+    ) throws IOException, GroupNotFoundException, NotAGroupMemberException {
+        final GroupInfo g = getGroupForSending(groupId);
 
-        SignalServiceDataMessage.Builder messageBuilder = SignalServiceDataMessage.newBuilder().asGroupMessage(group);
+        GroupUtils.setGroupContext(messageBuilder, g);
+        messageBuilder.withExpiration(g.getMessageExpirationTime());
 
-        final GroupInfo g = getGroupForSending(groupId);
+        return sendMessage(messageBuilder, g.getMembersWithout(account.getSelfAddress()));
+    }
+
+    public Pair<Long, List<SendMessageResult>> sendQuitGroupMessage(GroupId groupId) throws GroupNotFoundException, IOException, NotAGroupMemberException {
+        SignalServiceDataMessage.Builder messageBuilder;
+
+        final GroupInfo g = getGroupForUpdating(groupId);
         if (g instanceof GroupInfoV1) {
             GroupInfoV1 groupInfoV1 = (GroupInfoV1) g;
+            SignalServiceGroup group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.QUIT)
+                    .withId(groupId.serialize())
+                    .build();
+            messageBuilder = SignalServiceDataMessage.newBuilder().asGroupMessage(group);
             groupInfoV1.removeMember(account.getSelfAddress());
             account.getGroupStore().updateGroup(groupInfoV1);
         } else {
-            throw new RuntimeException("TODO Not implemented!");
+            final GroupInfoV2 groupInfoV2 = (GroupInfoV2) g;
+            final Pair<DecryptedGroup, GroupChange> groupGroupChangePair = groupHelper.leaveGroup(groupInfoV2);
+            groupInfoV2.setGroup(groupGroupChangePair.first());
+            messageBuilder = getGroupUpdateMessageBuilder(groupInfoV2, groupGroupChangePair.second().toByteArray());
+            account.getGroupStore().updateGroup(groupInfoV2);
         }
 
         return sendMessage(messageBuilder, g.getMembersWithout(account.getSelfAddress()));
     }
 
-    private GroupInfoV2 createGroupV2(
-            String name, Collection<SignalServiceAddress> members, InputStream avatar
-    ) throws IOException {
-        byte[] avatarBytes = avatar == null ? null : IOUtils.readFully(avatar);
-        final GroupsV2Operations.NewGroup newGroup = groupHelper.createGroupV2(name, members, avatarBytes);
-        final GroupSecretParams groupSecretParams = newGroup.getGroupSecretParams();
-
-        final GroupsV2AuthorizationString groupAuthForToday;
-        final DecryptedGroup decryptedGroup;
-        try {
-            groupAuthForToday = getGroupAuthForToday(groupSecretParams);
-            groupsV2Api.putNewGroup(newGroup, groupAuthForToday);
-            decryptedGroup = groupsV2Api.getGroup(groupSecretParams, groupAuthForToday);
-        } catch (IOException | VerificationFailedException | InvalidGroupStateException e) {
-            System.err.println("Failed to create V2 group: " + e.getMessage());
-            return null;
-        }
-        if (decryptedGroup == null) {
-            System.err.println("Failed to create V2 group!");
-            return null;
-        }
-
-        final byte[] groupId = groupSecretParams.getPublicParams().getGroupIdentifier().serialize();
-        final GroupMasterKey masterKey = groupSecretParams.getMasterKey();
-        GroupInfoV2 g = new GroupInfoV2(groupId, masterKey);
-        g.setGroup(decryptedGroup);
-
-        return g;
+    public Pair<GroupId, List<SendMessageResult>> updateGroup(
+            GroupId groupId, String name, List<String> members, File avatarFile
+    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, InvalidNumberException, NotAGroupMemberException {
+        return sendUpdateGroupMessage(groupId,
+                name,
+                members == null ? null : getSignalServiceAddresses(members),
+                avatarFile);
     }
 
-    private Pair<byte[], List<SendMessageResult>> sendUpdateGroupMessage(
-            byte[] groupId, String name, Collection<SignalServiceAddress> members, String avatarFile
+    private Pair<GroupId, List<SendMessageResult>> sendUpdateGroupMessage(
+            GroupId groupId, String name, Collection<SignalServiceAddress> members, File avatarFile
     ) throws IOException, GroupNotFoundException, AttachmentInvalidException, NotAGroupMemberException {
         GroupInfo g;
         SignalServiceDataMessage.Builder messageBuilder;
         if (groupId == null) {
             // Create new group
-            InputStream avatar = avatarFile == null ? null : new FileInputStream(avatarFile);
-            GroupInfoV2 gv2 = createGroupV2(name, members, avatar);
+            GroupInfoV2 gv2 = groupHelper.createGroupV2(name == null ? "" : name,
+                    members == null ? List.of() : members,
+                    avatarFile);
             if (gv2 == null) {
-                GroupInfoV1 gv1 = new GroupInfoV1(KeyUtils.createGroupId());
-                gv1.addMembers(Collections.singleton(account.getSelfAddress()));
+                GroupInfoV1 gv1 = new GroupInfoV1(GroupIdV1.createRandom());
+                gv1.addMembers(List.of(account.getSelfAddress()));
                 updateGroupV1(gv1, name, members, avatarFile);
                 messageBuilder = getGroupUpdateMessageBuilder(gv1);
                 g = gv1;
             } else {
-                messageBuilder = getGroupUpdateMessageBuilder(gv2);
+                if (avatarFile != null) {
+                    avatarStore.storeGroupAvatar(gv2.getGroupId(),
+                            outputStream -> IOUtils.copyFileToStream(avatarFile, outputStream));
+                }
+                messageBuilder = getGroupUpdateMessageBuilder(gv2, null);
                 g = gv2;
             }
         } else {
-            GroupInfo group = getGroupForSending(groupId);
-            if (!(group instanceof GroupInfoV1)) {
-                throw new RuntimeException("TODO Not implemented!");
+            GroupInfo group = getGroupForUpdating(groupId);
+            if (group instanceof GroupInfoV2) {
+                final GroupInfoV2 groupInfoV2 = (GroupInfoV2) group;
+
+                Pair<Long, List<SendMessageResult>> result = null;
+                if (groupInfoV2.isPendingMember(getSelfAddress())) {
+                    Pair<DecryptedGroup, GroupChange> groupGroupChangePair = groupHelper.acceptInvite(groupInfoV2);
+                    result = sendUpdateGroupMessage(groupInfoV2,
+                            groupGroupChangePair.first(),
+                            groupGroupChangePair.second());
+                }
+
+                if (members != null) {
+                    final Set<SignalServiceAddress> newMembers = new HashSet<>(members);
+                    newMembers.removeAll(group.getMembers()
+                            .stream()
+                            .map(this::resolveSignalServiceAddress)
+                            .collect(Collectors.toSet()));
+                    if (newMembers.size() > 0) {
+                        Pair<DecryptedGroup, GroupChange> groupGroupChangePair = groupHelper.updateGroupV2(groupInfoV2,
+                                newMembers);
+                        result = sendUpdateGroupMessage(groupInfoV2,
+                                groupGroupChangePair.first(),
+                                groupGroupChangePair.second());
+                    }
+                }
+                if (result == null || name != null || avatarFile != null) {
+                    Pair<DecryptedGroup, GroupChange> groupGroupChangePair = groupHelper.updateGroupV2(groupInfoV2,
+                            name,
+                            avatarFile);
+                    if (avatarFile != null) {
+                        avatarStore.storeGroupAvatar(groupInfoV2.getGroupId(),
+                                outputStream -> IOUtils.copyFileToStream(avatarFile, outputStream));
+                    }
+                    result = sendUpdateGroupMessage(groupInfoV2,
+                            groupGroupChangePair.first(),
+                            groupGroupChangePair.second());
+                }
+
+                return new Pair<>(group.getGroupId(), result.second());
+            } else {
+                GroupInfoV1 gv1 = (GroupInfoV1) group;
+                updateGroupV1(gv1, name, members, avatarFile);
+                messageBuilder = getGroupUpdateMessageBuilder(gv1);
+                g = gv1;
             }
-            GroupInfoV1 gv1 = (GroupInfoV1) group;
-            updateGroupV1(gv1, name, members, avatarFile);
-            messageBuilder = getGroupUpdateMessageBuilder(gv1);
-            g = gv1;
         }
 
         account.getGroupStore().updateGroup(g);
 
         final Pair<Long, List<SendMessageResult>> result = sendMessage(messageBuilder,
-                g.getMembersWithout(account.getSelfAddress()));
-        return new Pair<>(g.groupId, result.second());
+                g.getMembersIncludingPendingWithout(account.getSelfAddress()));
+        return new Pair<>(g.getGroupId(), result.second());
     }
 
     private void updateGroupV1(
             final GroupInfoV1 g,
             final String name,
             final Collection<SignalServiceAddress> members,
-            final String avatarFile
+            final File avatarFile
     ) throws IOException {
         if (name != null) {
             g.name = name;
@@ -838,14 +804,12 @@ public class Manager implements Closeable {
                 newE164Members.add(member.getNumber().get());
             }
 
-            final List<ContactTokenDetails> contacts = accountManager.getContacts(newE164Members);
-            if (contacts.size() != newE164Members.size()) {
+            final Map<String, UUID> registeredUsers = getRegisteredUsers(newE164Members);
+            if (registeredUsers.size() != newE164Members.size()) {
                 // Some of the new members are not registered on Signal
-                for (ContactTokenDetails contact : contacts) {
-                    newE164Members.remove(contact.getNumber());
-                }
+                newE164Members.removeAll(registeredUsers.keySet());
                 throw new IOException("Failed to add members "
-                        + Util.join(", ", newE164Members)
+                        + String.join(", ", newE164Members)
                         + " to group: Not registered on Signal");
             }
 
@@ -853,14 +817,73 @@ public class Manager implements Closeable {
         }
 
         if (avatarFile != null) {
-            IOUtils.createPrivateDirectories(pathConfig.getAvatarsPath());
-            File aFile = getGroupAvatarFile(g.groupId);
-            Files.copy(Paths.get(avatarFile), aFile.toPath(), StandardCopyOption.REPLACE_EXISTING);
+            avatarStore.storeGroupAvatar(g.getGroupId(),
+                    outputStream -> IOUtils.copyFileToStream(avatarFile, outputStream));
+        }
+    }
+
+    public Pair<GroupId, List<SendMessageResult>> joinGroup(
+            GroupInviteLinkUrl inviteLinkUrl
+    ) throws IOException, GroupLinkNotActiveException {
+        return sendJoinGroupMessage(inviteLinkUrl);
+    }
+
+    private Pair<GroupId, List<SendMessageResult>> sendJoinGroupMessage(
+            GroupInviteLinkUrl inviteLinkUrl
+    ) throws IOException, GroupLinkNotActiveException {
+        final DecryptedGroupJoinInfo groupJoinInfo = groupHelper.getDecryptedGroupJoinInfo(inviteLinkUrl.getGroupMasterKey(),
+                inviteLinkUrl.getPassword());
+        final GroupChange groupChange = groupHelper.joinGroup(inviteLinkUrl.getGroupMasterKey(),
+                inviteLinkUrl.getPassword(),
+                groupJoinInfo);
+        final GroupInfoV2 group = getOrMigrateGroup(inviteLinkUrl.getGroupMasterKey(),
+                groupJoinInfo.getRevision() + 1,
+                groupChange.toByteArray());
+
+        if (group.getGroup() == null) {
+            // Only requested member, can't send update to group members
+            return new Pair<>(group.getGroupId(), List.of());
         }
+
+        final Pair<Long, List<SendMessageResult>> result = sendUpdateGroupMessage(group, group.getGroup(), groupChange);
+
+        return new Pair<>(group.getGroupId(), result.second());
+    }
+
+    private static int currentTimeDays() {
+        return (int) TimeUnit.MILLISECONDS.toDays(System.currentTimeMillis());
     }
 
-    Pair<Long, List<SendMessageResult>> sendUpdateGroupMessage(
-            byte[] groupId, SignalServiceAddress recipient
+    private GroupsV2AuthorizationString getGroupAuthForToday(
+            final GroupSecretParams groupSecretParams
+    ) throws IOException {
+        final int today = currentTimeDays();
+        // Returns credentials for the next 7 days
+        final HashMap<Integer, AuthCredentialResponse> credentials = groupsV2Api.getCredentials(today);
+        // TODO cache credentials until they expire
+        AuthCredentialResponse authCredentialResponse = credentials.get(today);
+        try {
+            return groupsV2Api.getGroupsV2AuthorizationString(account.getUuid(),
+                    today,
+                    groupSecretParams,
+                    authCredentialResponse);
+        } catch (VerificationFailedException e) {
+            throw new IOException(e);
+        }
+    }
+
+    private Pair<Long, List<SendMessageResult>> sendUpdateGroupMessage(
+            GroupInfoV2 group, DecryptedGroup newDecryptedGroup, GroupChange groupChange
+    ) throws IOException {
+        group.setGroup(newDecryptedGroup);
+        final SignalServiceDataMessage.Builder messageBuilder = getGroupUpdateMessageBuilder(group,
+                groupChange.toByteArray());
+        account.getGroupStore().updateGroup(group);
+        return sendMessage(messageBuilder, group.getMembersIncludingPendingWithout(account.getSelfAddress()));
+    }
+
+    Pair<Long, List<SendMessageResult>> sendGroupInfoMessage(
+            GroupIdV1 groupId, SignalServiceAddress recipient
     ) throws IOException, NotAGroupMemberException, GroupNotFoundException, AttachmentInvalidException {
         GroupInfoV1 g;
         GroupInfo group = getGroupForSending(groupId);
@@ -876,22 +899,22 @@ public class Manager implements Closeable {
         SignalServiceDataMessage.Builder messageBuilder = getGroupUpdateMessageBuilder(g);
 
         // Send group message only to the recipient who requested it
-        return sendMessage(messageBuilder, Collections.singleton(recipient));
+        return sendMessage(messageBuilder, List.of(recipient));
     }
 
     private SignalServiceDataMessage.Builder getGroupUpdateMessageBuilder(GroupInfoV1 g) throws AttachmentInvalidException {
         SignalServiceGroup.Builder group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.UPDATE)
-                .withId(g.groupId)
+                .withId(g.getGroupId().serialize())
                 .withName(g.name)
                 .withMembers(new ArrayList<>(g.getMembers()));
 
-        File aFile = getGroupAvatarFile(g.groupId);
-        if (aFile.exists()) {
-            try {
-                group.withAvatar(Utils.createAttachment(aFile));
-            } catch (IOException e) {
-                throw new AttachmentInvalidException(aFile.toString(), e);
+        try {
+            final Optional<SignalServiceAttachmentStream> attachment = createGroupAvatarAttachment(g.getGroupId());
+            if (attachment.isPresent()) {
+                group.withAvatar(attachment.get());
             }
+        } catch (IOException e) {
+            throw new AttachmentInvalidException(g.getGroupId().toBase64(), e);
         }
 
         return SignalServiceDataMessage.newBuilder()
@@ -899,34 +922,33 @@ public class Manager implements Closeable {
                 .withExpiration(g.getMessageExpirationTime());
     }
 
-    private SignalServiceDataMessage.Builder getGroupUpdateMessageBuilder(GroupInfoV2 g) {
+    private SignalServiceDataMessage.Builder getGroupUpdateMessageBuilder(GroupInfoV2 g, byte[] signedGroupChange) {
         SignalServiceGroupV2.Builder group = SignalServiceGroupV2.newBuilder(g.getMasterKey())
                 .withRevision(g.getGroup().getRevision())
-//                .withSignedGroupChange() // TODO
-                ;
+                .withSignedGroupChange(signedGroupChange);
         return SignalServiceDataMessage.newBuilder()
                 .asGroupMessage(group.build())
                 .withExpiration(g.getMessageExpirationTime());
     }
 
     Pair<Long, List<SendMessageResult>> sendGroupInfoRequest(
-            byte[] groupId, SignalServiceAddress recipient
+            GroupIdV1 groupId, SignalServiceAddress recipient
     ) throws IOException {
         SignalServiceGroup.Builder group = SignalServiceGroup.newBuilder(SignalServiceGroup.Type.REQUEST_INFO)
-                .withId(groupId);
+                .withId(groupId.serialize());
 
         SignalServiceDataMessage.Builder messageBuilder = SignalServiceDataMessage.newBuilder()
                 .asGroupMessage(group.build());
 
         // Send group info request message to the recipient who sent us a message with this groupId
-        return sendMessage(messageBuilder, Collections.singleton(recipient));
+        return sendMessage(messageBuilder, List.of(recipient));
     }
 
     void sendReceipt(
             SignalServiceAddress remoteAddress, long messageId
     ) throws IOException, UntrustedIdentityException {
         SignalServiceReceiptMessage receiptMessage = new SignalServiceReceiptMessage(SignalServiceReceiptMessage.Type.DELIVERY,
-                Collections.singletonList(messageId),
+                List.of(messageId),
                 System.currentTimeMillis());
 
         createMessageSender().sendReceipt(remoteAddress,
@@ -940,7 +962,7 @@ public class Manager implements Closeable {
         final SignalServiceDataMessage.Builder messageBuilder = SignalServiceDataMessage.newBuilder()
                 .withBody(messageText);
         if (attachments != null) {
-            List<SignalServiceAttachment> attachmentStreams = Utils.getSignalServiceAttachments(attachments);
+            List<SignalServiceAttachment> attachmentStreams = AttachmentUtils.getSignalServiceAttachments(attachments);
 
             // Upload attachments here, so we only upload once even for multiple recipients
             SignalServiceMessageSender messageSender = createMessageSender();
@@ -958,6 +980,17 @@ public class Manager implements Closeable {
         return sendMessage(messageBuilder, getSignalServiceAddresses(recipients));
     }
 
+    public Pair<Long, SendMessageResult> sendSelfMessage(
+            String messageText, List<String> attachments
+    ) throws IOException, AttachmentInvalidException {
+        final SignalServiceDataMessage.Builder messageBuilder = SignalServiceDataMessage.newBuilder()
+                .withBody(messageText);
+        if (attachments != null) {
+            messageBuilder.withAttachments(AttachmentUtils.getSignalServiceAttachments(attachments));
+        }
+        return sendSelfMessage(messageBuilder);
+    }
+
     public Pair<Long, List<SendMessageResult>> sendMessageReaction(
             String emoji, boolean remove, String targetAuthor, long targetSentTimestamp, List<String> recipients
     ) throws IOException, InvalidNumberException {
@@ -1019,7 +1052,7 @@ public class Manager implements Closeable {
         account.save();
     }
 
-    public void setGroupBlocked(final byte[] groupId, final boolean blocked) throws GroupNotFoundException {
+    public void setGroupBlocked(final GroupId groupId, final boolean blocked) throws GroupNotFoundException {
         GroupInfo group = getGroup(groupId);
         if (group == null) {
             throw new GroupNotFoundException(groupId);
@@ -1030,15 +1063,6 @@ public class Manager implements Closeable {
         account.save();
     }
 
-    public Pair<byte[], List<SendMessageResult>> updateGroup(
-            byte[] groupId, String name, List<String> members, String avatar
-    ) throws IOException, GroupNotFoundException, AttachmentInvalidException, InvalidNumberException, NotAGroupMemberException {
-        return sendUpdateGroupMessage(groupId,
-                name,
-                members == null ? null : getSignalServiceAddresses(members),
-                avatar);
-    }
-
     /**
      * Change the expiration timer for a contact
      */
@@ -1053,7 +1077,7 @@ public class Manager implements Closeable {
     private void sendExpirationTimerUpdate(SignalServiceAddress address) throws IOException {
         final SignalServiceDataMessage.Builder messageBuilder = SignalServiceDataMessage.newBuilder()
                 .asExpirationUpdate();
-        sendMessage(messageBuilder, Collections.singleton(address));
+        sendMessage(messageBuilder, List.of(address));
     }
 
     /**
@@ -1069,8 +1093,8 @@ public class Manager implements Closeable {
     /**
      * Change the expiration timer for a group
      */
-    public void setExpirationTimer(byte[] groupId, int messageExpirationTimer) {
-        GroupInfo g = account.getGroupStore().getGroup(groupId);
+    public void setExpirationTimer(GroupId groupId, int messageExpirationTimer) {
+        GroupInfo g = getGroup(groupId);
         if (g instanceof GroupInfoV1) {
             GroupInfoV1 groupInfoV1 = (GroupInfoV1) g;
             groupInfoV1.messageExpirationTime = messageExpirationTimer;
@@ -1086,8 +1110,8 @@ public class Manager implements Closeable {
      * @param path Path can be a path to a manifest.json file or to a zip file that contains a manifest.json file
      * @return if successful, returns the URL to install the sticker pack in the signal app
      */
-    public String uploadStickerPack(String path) throws IOException, StickerPackInvalidException {
-        SignalServiceStickerManifestUpload manifest = getSignalServiceStickerManifestUpload(path);
+    public String uploadStickerPack(File path) throws IOException, StickerPackInvalidException {
+        SignalServiceStickerManifestUpload manifest = StickerUtils.getSignalServiceStickerManifestUpload(path);
 
         SignalServiceMessageSender messageSender = createMessageSender();
 
@@ -1110,97 +1134,6 @@ public class Manager implements Closeable {
         }
     }
 
-    private SignalServiceStickerManifestUpload getSignalServiceStickerManifestUpload(
-            final String path
-    ) throws IOException, StickerPackInvalidException {
-        ZipFile zip = null;
-        String rootPath = null;
-
-        final File file = new File(path);
-        if (file.getName().endsWith(".zip")) {
-            zip = new ZipFile(file);
-        } else if (file.getName().equals("manifest.json")) {
-            rootPath = file.getParent();
-        } else {
-            throw new StickerPackInvalidException("Could not find manifest.json");
-        }
-
-        JsonStickerPack pack = parseStickerPack(rootPath, zip);
-
-        if (pack.stickers == null) {
-            throw new StickerPackInvalidException("Must set a 'stickers' field.");
-        }
-
-        if (pack.stickers.isEmpty()) {
-            throw new StickerPackInvalidException("Must include stickers.");
-        }
-
-        List<StickerInfo> stickers = new ArrayList<>(pack.stickers.size());
-        for (JsonStickerPack.JsonSticker sticker : pack.stickers) {
-            if (sticker.file == null) {
-                throw new StickerPackInvalidException("Must set a 'file' field on each sticker.");
-            }
-
-            Pair<InputStream, Long> data;
-            try {
-                data = getInputStreamAndLength(rootPath, zip, sticker.file);
-            } catch (IOException ignored) {
-                throw new StickerPackInvalidException("Could not find find " + sticker.file);
-            }
-
-            String contentType = Utils.getFileMimeType(new File(sticker.file), null);
-            StickerInfo stickerInfo = new StickerInfo(data.first(),
-                    data.second(),
-                    Optional.fromNullable(sticker.emoji).or(""),
-                    contentType);
-            stickers.add(stickerInfo);
-        }
-
-        StickerInfo cover = null;
-        if (pack.cover != null) {
-            if (pack.cover.file == null) {
-                throw new StickerPackInvalidException("Must set a 'file' field on the cover.");
-            }
-
-            Pair<InputStream, Long> data;
-            try {
-                data = getInputStreamAndLength(rootPath, zip, pack.cover.file);
-            } catch (IOException ignored) {
-                throw new StickerPackInvalidException("Could not find find " + pack.cover.file);
-            }
-
-            String contentType = Utils.getFileMimeType(new File(pack.cover.file), null);
-            cover = new StickerInfo(data.first(),
-                    data.second(),
-                    Optional.fromNullable(pack.cover.emoji).or(""),
-                    contentType);
-        }
-
-        return new SignalServiceStickerManifestUpload(pack.title, pack.author, cover, stickers);
-    }
-
-    private static JsonStickerPack parseStickerPack(String rootPath, ZipFile zip) throws IOException {
-        InputStream inputStream;
-        if (zip != null) {
-            inputStream = zip.getInputStream(zip.getEntry("manifest.json"));
-        } else {
-            inputStream = new FileInputStream((new File(rootPath, "manifest.json")));
-        }
-        return new ObjectMapper().readValue(inputStream, JsonStickerPack.class);
-    }
-
-    private static Pair<InputStream, Long> getInputStreamAndLength(
-            final String rootPath, final ZipFile zip, final String subfile
-    ) throws IOException {
-        if (zip != null) {
-            final ZipEntry entry = zip.getEntry(subfile);
-            return new Pair<>(zip.getInputStream(entry), entry.getSize());
-        } else {
-            final File file = new File(rootPath, subfile);
-            return new Pair<>(new FileInputStream(file), file.length());
-        }
-    }
-
     void requestSyncGroups() throws IOException {
         SignalServiceProtos.SyncMessage.Request r = SignalServiceProtos.SyncMessage.Request.newBuilder()
                 .setType(SignalServiceProtos.SyncMessage.Request.Type.GROUPS)
@@ -1209,7 +1142,7 @@ public class Manager implements Closeable {
         try {
             sendSyncMessage(message);
         } catch (UntrustedIdentityException e) {
-            e.printStackTrace();
+            throw new AssertionError(e);
         }
     }
 
@@ -1221,7 +1154,7 @@ public class Manager implements Closeable {
         try {
             sendSyncMessage(message);
         } catch (UntrustedIdentityException e) {
-            e.printStackTrace();
+            throw new AssertionError(e);
         }
     }
 
@@ -1233,7 +1166,7 @@ public class Manager implements Closeable {
         try {
             sendSyncMessage(message);
         } catch (UntrustedIdentityException e) {
-            e.printStackTrace();
+            throw new AssertionError(e);
         }
     }
 
@@ -1245,7 +1178,19 @@ public class Manager implements Closeable {
         try {
             sendSyncMessage(message);
         } catch (UntrustedIdentityException e) {
-            e.printStackTrace();
+            throw new AssertionError(e);
+        }
+    }
+
+    void requestSyncKeys() throws IOException {
+        SignalServiceProtos.SyncMessage.Request r = SignalServiceProtos.SyncMessage.Request.newBuilder()
+                .setType(SignalServiceProtos.SyncMessage.Request.Type.KEYS)
+                .build();
+        SignalServiceSyncMessage message = SignalServiceSyncMessage.forRequest(new RequestMessage(r));
+        try {
+            sendSyncMessage(message);
+        } catch (UntrustedIdentityException e) {
+            throw new AssertionError(e);
         }
     }
 
@@ -1256,7 +1201,7 @@ public class Manager implements Closeable {
         try {
             certificate = accountManager.getSenderCertificate();
         } catch (IOException e) {
-            System.err.println("Failed to get sender certificate: " + e);
+            logger.warn("Failed to get sender certificate, ignoring: {}", e.getMessage());
             return null;
         }
         // TODO cache for a day
@@ -1278,13 +1223,51 @@ public class Manager implements Closeable {
 
     private Collection<SignalServiceAddress> getSignalServiceAddresses(Collection<String> numbers) throws InvalidNumberException {
         final Set<SignalServiceAddress> signalServiceAddresses = new HashSet<>(numbers.size());
+        final Set<SignalServiceAddress> addressesMissingUuid = new HashSet<>();
 
         for (String number : numbers) {
-            signalServiceAddresses.add(canonicalizeAndResolveSignalServiceAddress(number));
+            final SignalServiceAddress resolvedAddress = canonicalizeAndResolveSignalServiceAddress(number);
+            if (resolvedAddress.getUuid().isPresent()) {
+                signalServiceAddresses.add(resolvedAddress);
+            } else {
+                addressesMissingUuid.add(resolvedAddress);
+            }
         }
+
+        final Set<String> numbersMissingUuid = addressesMissingUuid.stream()
+                .map(a -> a.getNumber().get())
+                .collect(Collectors.toSet());
+        Map<String, UUID> registeredUsers;
+        try {
+            registeredUsers = getRegisteredUsers(numbersMissingUuid);
+        } catch (IOException e) {
+            logger.warn("Failed to resolve uuids from server, ignoring: {}", e.getMessage());
+            registeredUsers = Map.of();
+        }
+
+        for (SignalServiceAddress address : addressesMissingUuid) {
+            final String number = address.getNumber().get();
+            if (registeredUsers.containsKey(number)) {
+                final SignalServiceAddress newAddress = resolveSignalServiceAddress(new SignalServiceAddress(
+                        registeredUsers.get(number),
+                        number));
+                signalServiceAddresses.add(newAddress);
+            } else {
+                signalServiceAddresses.add(address);
+            }
+        }
+
         return signalServiceAddresses;
     }
 
+    private Map<String, UUID> getRegisteredUsers(final Set<String> numbersMissingUuid) throws IOException {
+        try {
+            return accountManager.getRegisteredUsers(getIasKeyStore(), numbersMissingUuid, CDS_MRENCLAVE);
+        } catch (Quote.InvalidQuoteFormatException | UnauthenticatedQuoteException | SignatureException | UnauthenticatedResponseException | InvalidKeyException e) {
+            throw new IOException(e);
+        }
+    }
+
     private Pair<Long, List<SendMessageResult>> sendMessage(
             SignalServiceDataMessage.Builder messageBuilder, Collection<SignalServiceAddress> recipients
     ) throws IOException {
@@ -1318,26 +1301,18 @@ public class Manager implements Closeable {
                             .saveIdentity(resolveSignalServiceAddress(e.getIdentifier()),
                                     e.getIdentityKey(),
                                     TrustLevel.UNTRUSTED);
-                    return new Pair<>(timestamp, Collections.emptyList());
+                    return new Pair<>(timestamp, List.of());
                 }
             } else {
                 // Send to all individually, so sync messages are sent correctly
+                messageBuilder.withProfileKey(account.getProfileKey().serialize());
                 List<SendMessageResult> results = new ArrayList<>(recipients.size());
                 for (SignalServiceAddress address : recipients) {
-                    ContactInfo contact = account.getContactStore().getContact(address);
-                    if (contact != null) {
-                        messageBuilder.withExpiration(contact.messageExpirationTime);
-                        messageBuilder.withProfileKey(account.getProfileKey().serialize());
-                    } else {
-                        messageBuilder.withExpiration(0);
-                        messageBuilder.withProfileKey(null);
-                    }
+                    final ContactInfo contact = account.getContactStore().getContact(address);
+                    final int expirationTime = contact != null ? contact.messageExpirationTime : 0;
+                    messageBuilder.withExpiration(expirationTime);
                     message = messageBuilder.build();
-                    if (address.matches(account.getSelfAddress())) {
-                        results.add(sendSelfMessage(message));
-                    } else {
-                        results.add(sendMessage(address, message));
-                    }
+                    results.add(sendMessage(address, message));
                 }
                 return new Pair<>(timestamp, results);
             }
@@ -1351,6 +1326,28 @@ public class Manager implements Closeable {
         }
     }
 
+    private Pair<Long, SendMessageResult> sendSelfMessage(
+            SignalServiceDataMessage.Builder messageBuilder
+    ) throws IOException {
+        final long timestamp = System.currentTimeMillis();
+        messageBuilder.withTimestamp(timestamp);
+        getOrCreateMessagePipe();
+        getOrCreateUnidentifiedMessagePipe();
+        try {
+            final SignalServiceAddress address = getSelfAddress();
+
+            final ContactInfo contact = account.getContactStore().getContact(address);
+            final int expirationTime = contact != null ? contact.messageExpirationTime : 0;
+            messageBuilder.withExpiration(expirationTime);
+
+            SignalServiceDataMessage message = messageBuilder.build();
+            final SendMessageResult result = sendSelfMessage(message);
+            return new Pair<>(timestamp, result);
+        } finally {
+            account.save();
+        }
+    }
+
     private SendMessageResult sendSelfMessage(SignalServiceDataMessage message) throws IOException {
         SignalServiceMessageSender messageSender = createMessageSender();
 
@@ -1361,7 +1358,7 @@ public class Manager implements Closeable {
                 message.getTimestamp(),
                 message,
                 message.getExpiresInSeconds(),
-                Collections.singletonMap(recipient, unidentifiedAccess.isPresent()),
+                Map.of(recipient, unidentifiedAccess.isPresent()),
                 false);
         SignalServiceSyncMessage syncMessage = SignalServiceSyncMessage.forSentTranscript(transcript);
 
@@ -1400,17 +1397,20 @@ public class Manager implements Closeable {
     private SignalServiceContent decryptMessage(SignalServiceEnvelope envelope) throws InvalidMetadataMessageException, ProtocolInvalidMessageException, ProtocolDuplicateMessageException, ProtocolLegacyMessageException, ProtocolInvalidKeyIdException, InvalidMetadataVersionException, ProtocolInvalidVersionException, ProtocolNoSessionException, ProtocolInvalidKeyException, SelfSendException, UnsupportedDataMessageException, org.whispersystems.libsignal.UntrustedIdentityException {
         SignalServiceCipher cipher = new SignalServiceCipher(account.getSelfAddress(),
                 account.getSignalProtocolStore(),
-                Utils.getCertificateValidator());
+                certificateValidator);
         try {
             return cipher.decrypt(envelope);
         } catch (ProtocolUntrustedIdentityException e) {
             if (e.getCause() instanceof org.whispersystems.libsignal.UntrustedIdentityException) {
                 org.whispersystems.libsignal.UntrustedIdentityException identityException = (org.whispersystems.libsignal.UntrustedIdentityException) e
                         .getCause();
-                account.getSignalProtocolStore()
-                        .saveIdentity(resolveSignalServiceAddress(identityException.getName()),
-                                identityException.getUntrustedIdentity(),
-                                TrustLevel.UNTRUSTED);
+                final IdentityKey untrustedIdentity = identityException.getUntrustedIdentity();
+                if (untrustedIdentity != null) {
+                    account.getSignalProtocolStore()
+                            .saveIdentity(resolveSignalServiceAddress(identityException.getName()),
+                                    untrustedIdentity,
+                                    TrustLevel.UNTRUSTED);
+                }
                 throw identityException;
             }
             throw new AssertionError(e);
@@ -1421,24 +1421,6 @@ public class Manager implements Closeable {
         account.getSignalProtocolStore().deleteAllSessions(source);
     }
 
-    private static int currentTimeDays() {
-        return (int) TimeUnit.MILLISECONDS.toDays(System.currentTimeMillis());
-    }
-
-    private GroupsV2AuthorizationString getGroupAuthForToday(
-            final GroupSecretParams groupSecretParams
-    ) throws IOException, VerificationFailedException {
-        final int today = currentTimeDays();
-        // Returns credentials for the next 7 days
-        final HashMap<Integer, AuthCredentialResponse> credentials = groupsV2Api.getCredentials(today);
-        // TODO cache credentials until they expire
-        AuthCredentialResponse authCredentialResponse = credentials.get(today);
-        return groupsV2Api.getGroupsV2AuthorizationString(account.getUuid(),
-                today,
-                groupSecretParams,
-                authCredentialResponse);
-    }
-
     private List<HandleAction> handleSignalServiceDataMessage(
             SignalServiceDataMessage message,
             boolean isSync,
@@ -1450,25 +1432,19 @@ public class Manager implements Closeable {
         if (message.getGroupContext().isPresent()) {
             if (message.getGroupContext().get().getGroupV1().isPresent()) {
                 SignalServiceGroup groupInfo = message.getGroupContext().get().getGroupV1().get();
-                GroupInfo group = account.getGroupStore().getGroupByV1Id(groupInfo.getGroupId());
+                GroupIdV1 groupId = GroupId.v1(groupInfo.getGroupId());
+                GroupInfo group = getGroup(groupId);
                 if (group == null || group instanceof GroupInfoV1) {
                     GroupInfoV1 groupV1 = (GroupInfoV1) group;
                     switch (groupInfo.getType()) {
                         case UPDATE: {
                             if (groupV1 == null) {
-                                groupV1 = new GroupInfoV1(groupInfo.getGroupId());
+                                groupV1 = new GroupInfoV1(groupId);
                             }
 
                             if (groupInfo.getAvatar().isPresent()) {
                                 SignalServiceAttachment avatar = groupInfo.getAvatar().get();
-                                if (avatar.isPointer()) {
-                                    try {
-                                        retrieveGroupAvatarAttachment(avatar.asPointer(), groupV1.groupId);
-                                    } catch (IOException | InvalidMessageException | MissingConfigurationException e) {
-                                        System.err.println("Failed to retrieve group avatar (" + avatar.asPointer()
-                                                .getRemoteId() + "): " + e.getMessage());
-                                    }
-                                }
+                                downloadGroupAvatar(avatar, groupV1.getGroupId());
                             }
 
                             if (groupInfo.getName().isPresent()) {
@@ -1488,7 +1464,7 @@ public class Manager implements Closeable {
                         }
                         case DELIVER:
                             if (groupV1 == null && !isSync) {
-                                actions.add(new SendGroupInfoRequestAction(source, groupInfo.getGroupId()));
+                                actions.add(new SendGroupInfoRequestAction(source, groupId));
                             }
                             break;
                         case QUIT: {
@@ -1500,7 +1476,7 @@ public class Manager implements Closeable {
                         }
                         case REQUEST_INFO:
                             if (groupV1 != null && !isSync) {
-                                actions.add(new SendGroupUpdateAction(source, groupV1.groupId));
+                                actions.add(new SendGroupInfoAction(source, groupV1.getGroupId()));
                             }
                             break;
                     }
@@ -1512,54 +1488,21 @@ public class Manager implements Closeable {
                 final SignalServiceGroupV2 groupContext = message.getGroupContext().get().getGroupV2().get();
                 final GroupMasterKey groupMasterKey = groupContext.getMasterKey();
 
-                final GroupSecretParams groupSecretParams = GroupSecretParams.deriveFromMasterKey(groupMasterKey);
-
-                byte[] groupId = groupSecretParams.getPublicParams().getGroupIdentifier().serialize();
-                GroupInfo groupInfo = account.getGroupStore().getGroupByV2Id(groupId);
-                if (groupInfo instanceof GroupInfoV1) {
-                    // Received a v2 group message for a v2 group, we need to locally migrate the group
-                    account.getGroupStore().deleteGroup(groupInfo.groupId);
-                    GroupInfoV2 groupInfoV2 = new GroupInfoV2(groupId, groupMasterKey);
-                    groupInfoV2.setGroup(getDecryptedGroup(groupSecretParams));
-                    account.getGroupStore().updateGroup(groupInfoV2);
-                    System.err.println("Locally migrated group "
-                            + Base64.encodeBytes(groupInfo.groupId)
-                            + " to group v2, id: "
-                            + Base64.encodeBytes(groupInfoV2.groupId)
-                            + " !!!");
-                } else if (groupInfo == null || groupInfo instanceof GroupInfoV2) {
-                    GroupInfoV2 groupInfoV2 = groupInfo == null
-                            ? new GroupInfoV2(groupId, groupMasterKey)
-                            : (GroupInfoV2) groupInfo;
-
-                    if (groupInfoV2.getGroup() == null
-                            || groupInfoV2.getGroup().getRevision() < groupContext.getRevision()) {
-                        DecryptedGroup group = null;
-                        if (groupContext.hasSignedGroupChange()
-                                && groupInfoV2.getGroup() != null
-                                && groupInfoV2.getGroup().getRevision() + 1 == groupContext.getRevision()) {
-                            group = groupHelper.getUpdatedDecryptedGroup(groupInfoV2.getGroup(),
-                                    groupContext.getSignedGroupChange(),
-                                    groupMasterKey);
-                        }
-                        if (group == null) {
-                            group = getDecryptedGroup(groupSecretParams);
-                        }
-                        groupInfoV2.setGroup(group);
-                        account.getGroupStore().updateGroup(groupInfoV2);
-                    }
-                }
+                getOrMigrateGroup(groupMasterKey,
+                        groupContext.getRevision(),
+                        groupContext.hasSignedGroupChange() ? groupContext.getSignedGroupChange() : null);
             }
         }
+
         final SignalServiceAddress conversationPartnerAddress = isSync ? destination : source;
-        if (message.isEndSession()) {
+        if (conversationPartnerAddress != null && message.isEndSession()) {
             handleEndSession(conversationPartnerAddress);
         }
         if (message.isExpirationUpdate() || message.getBody().isPresent()) {
             if (message.getGroupContext().isPresent()) {
                 if (message.getGroupContext().get().getGroupV1().isPresent()) {
                     SignalServiceGroup groupInfo = message.getGroupContext().get().getGroupV1().get();
-                    GroupInfoV1 group = account.getGroupStore().getOrCreateGroupV1(groupInfo.getGroupId());
+                    GroupInfoV1 group = account.getGroupStore().getOrCreateGroupV1(GroupId.v1(groupInfo.getGroupId()));
                     if (group != null) {
                         if (group.messageExpirationTime != message.getExpiresInSeconds()) {
                             group.messageExpirationTime = message.getExpiresInSeconds();
@@ -1569,7 +1512,7 @@ public class Manager implements Closeable {
                 } else if (message.getGroupContext().get().getGroupV2().isPresent()) {
                     // disappearing message timer already stored in the DecryptedGroup
                 }
-            } else {
+            } else if (conversationPartnerAddress != null) {
                 ContactInfo contact = account.getContactStore().getContact(conversationPartnerAddress);
                 if (contact == null) {
                     contact = new ContactInfo(conversationPartnerAddress);
@@ -1582,16 +1525,7 @@ public class Manager implements Closeable {
         }
         if (message.getAttachments().isPresent() && !ignoreAttachments) {
             for (SignalServiceAttachment attachment : message.getAttachments().get()) {
-                if (attachment.isPointer()) {
-                    try {
-                        retrieveAttachment(attachment.asPointer());
-                    } catch (IOException | InvalidMessageException | MissingConfigurationException e) {
-                        System.err.println("Failed to retrieve attachment ("
-                                + attachment.asPointer().getRemoteId()
-                                + "): "
-                                + e.getMessage());
-                    }
-                }
+                downloadAttachment(attachment);
             }
         }
         if (message.getProfileKey().isPresent() && message.getProfileKey().get().length == 32) {
@@ -1609,16 +1543,18 @@ public class Manager implements Closeable {
         if (message.getPreviews().isPresent()) {
             final List<SignalServiceDataMessage.Preview> previews = message.getPreviews().get();
             for (SignalServiceDataMessage.Preview preview : previews) {
-                if (preview.getImage().isPresent() && preview.getImage().get().isPointer()) {
-                    SignalServiceAttachmentPointer attachment = preview.getImage().get().asPointer();
-                    try {
-                        retrieveAttachment(attachment);
-                    } catch (IOException | InvalidMessageException | MissingConfigurationException e) {
-                        System.err.println("Failed to retrieve attachment ("
-                                + attachment.getRemoteId()
-                                + "): "
-                                + e.getMessage());
-                    }
+                if (preview.getImage().isPresent()) {
+                    downloadAttachment(preview.getImage().get());
+                }
+            }
+        }
+        if (message.getQuote().isPresent()) {
+            final SignalServiceDataMessage.Quote quote = message.getQuote().get();
+
+            for (SignalServiceDataMessage.Quote.QuotedAttachment quotedAttachment : quote.getAttachments()) {
+                final SignalServiceAttachment thumbnail = quotedAttachment.getThumbnail();
+                if (thumbnail != null) {
+                    downloadAttachment(thumbnail);
                 }
             }
         }
@@ -1633,61 +1569,74 @@ public class Manager implements Closeable {
         return actions;
     }
 
-    private DecryptedGroup getDecryptedGroup(final GroupSecretParams groupSecretParams) {
-        try {
-            final GroupsV2AuthorizationString groupsV2AuthorizationString = getGroupAuthForToday(groupSecretParams);
-            DecryptedGroup group = groupsV2Api.getGroup(groupSecretParams, groupsV2AuthorizationString);
-            for (DecryptedMember member : group.getMembersList()) {
-                final SignalServiceAddress address = resolveSignalServiceAddress(new SignalServiceAddress(UuidUtil.parseOrThrow(
-                        member.getUuid().toByteArray()), null));
-                try {
-                    account.getProfileStore()
-                            .storeProfileKey(address, new ProfileKey(member.getProfileKey().toByteArray()));
-                } catch (InvalidInputException ignored) {
+    private GroupInfoV2 getOrMigrateGroup(
+            final GroupMasterKey groupMasterKey, final int revision, final byte[] signedGroupChange
+    ) {
+        final GroupSecretParams groupSecretParams = GroupSecretParams.deriveFromMasterKey(groupMasterKey);
+
+        GroupIdV2 groupId = GroupUtils.getGroupIdV2(groupSecretParams);
+        GroupInfo groupInfo = getGroup(groupId);
+        final GroupInfoV2 groupInfoV2;
+        if (groupInfo instanceof GroupInfoV1) {
+            // Received a v2 group message for a v1 group, we need to locally migrate the group
+            account.getGroupStore().deleteGroup(groupInfo.getGroupId());
+            groupInfoV2 = new GroupInfoV2(groupId, groupMasterKey);
+            logger.info("Locally migrated group {} to group v2, id: {}",
+                    groupInfo.getGroupId().toBase64(),
+                    groupInfoV2.getGroupId().toBase64());
+        } else if (groupInfo instanceof GroupInfoV2) {
+            groupInfoV2 = (GroupInfoV2) groupInfo;
+        } else {
+            groupInfoV2 = new GroupInfoV2(groupId, groupMasterKey);
+        }
+
+        if (groupInfoV2.getGroup() == null || groupInfoV2.getGroup().getRevision() < revision) {
+            DecryptedGroup group = null;
+            if (signedGroupChange != null
+                    && groupInfoV2.getGroup() != null
+                    && groupInfoV2.getGroup().getRevision() + 1 == revision) {
+                group = groupHelper.getUpdatedDecryptedGroup(groupInfoV2.getGroup(), signedGroupChange, groupMasterKey);
+            }
+            if (group == null) {
+                group = groupHelper.getDecryptedGroup(groupSecretParams);
+            }
+            if (group != null) {
+                storeProfileKeysFromMembers(group);
+                final String avatar = group.getAvatar();
+                if (avatar != null && !avatar.isEmpty()) {
+                    downloadGroupAvatar(groupId, groupSecretParams, avatar);
                 }
             }
-            return group;
-        } catch (IOException | VerificationFailedException | InvalidGroupStateException e) {
-            System.err.println("Failed to retrieve Group V2 info, ignoring ...");
-            return null;
+            groupInfoV2.setGroup(group);
+            account.getGroupStore().updateGroup(groupInfoV2);
         }
+
+        return groupInfoV2;
     }
 
-    private void retryFailedReceivedMessages(
-            ReceiveMessageHandler handler, boolean ignoreAttachments
-    ) {
-        final File cachePath = new File(getMessageCachePath());
-        if (!cachePath.exists()) {
-            return;
-        }
-        for (final File dir : Objects.requireNonNull(cachePath.listFiles())) {
-            if (!dir.isDirectory()) {
-                retryFailedReceivedMessage(handler, ignoreAttachments, dir);
-                continue;
+    private void storeProfileKeysFromMembers(final DecryptedGroup group) {
+        for (DecryptedMember member : group.getMembersList()) {
+            final SignalServiceAddress address = resolveSignalServiceAddress(new SignalServiceAddress(UuidUtil.parseOrThrow(
+                    member.getUuid().toByteArray()), null));
+            try {
+                account.getProfileStore()
+                        .storeProfileKey(address, new ProfileKey(member.getProfileKey().toByteArray()));
+            } catch (InvalidInputException ignored) {
             }
+        }
+    }
 
-            for (final File fileEntry : Objects.requireNonNull(dir.listFiles())) {
-                if (!fileEntry.isFile()) {
-                    continue;
-                }
-                retryFailedReceivedMessage(handler, ignoreAttachments, fileEntry);
-            }
-            // Try to delete directory if empty
-            dir.delete();
+    private void retryFailedReceivedMessages(ReceiveMessageHandler handler, boolean ignoreAttachments) {
+        for (CachedMessage cachedMessage : account.getMessageCache().getCachedMessages()) {
+            retryFailedReceivedMessage(handler, ignoreAttachments, cachedMessage);
         }
     }
 
     private void retryFailedReceivedMessage(
-            final ReceiveMessageHandler handler, final boolean ignoreAttachments, final File fileEntry
+            final ReceiveMessageHandler handler, final boolean ignoreAttachments, final CachedMessage cachedMessage
     ) {
-        SignalServiceEnvelope envelope;
-        try {
-            envelope = Utils.loadEnvelope(fileEntry);
-            if (envelope == null) {
-                return;
-            }
-        } catch (IOException e) {
-            e.printStackTrace();
+        SignalServiceEnvelope envelope = cachedMessage.loadEnvelope();
+        if (envelope == null) {
             return;
         }
         SignalServiceContent content = null;
@@ -1698,11 +1647,7 @@ public class Manager implements Closeable {
                 return;
             } catch (Exception er) {
                 // All other errors are not recoverable, so delete the cached message
-                try {
-                    Files.delete(fileEntry.toPath());
-                } catch (IOException e) {
-                    System.err.println("Failed to delete cached message file “" + fileEntry + "”: " + e.getMessage());
-                }
+                cachedMessage.delete();
                 return;
             }
             List<HandleAction> actions = handleMessage(envelope, content, ignoreAttachments);
@@ -1710,17 +1655,13 @@ public class Manager implements Closeable {
                 try {
                     action.execute(this);
                 } catch (Throwable e) {
-                    e.printStackTrace();
+                    logger.warn("Message action failed.", e);
                 }
             }
         }
         account.save();
         handler.handleMessage(envelope, content, null);
-        try {
-            Files.delete(fileEntry.toPath());
-        } catch (IOException e) {
-            System.err.println("Failed to delete cached message file “" + fileEntry + "”: " + e.getMessage());
-        }
+        cachedMessage.delete();
     }
 
     public void receiveMessages(
@@ -1734,7 +1675,7 @@ public class Manager implements Closeable {
 
         Set<HandleAction> queuedActions = null;
 
-        getOrCreateMessagePipe();
+        final SignalServiceMessagePipe messagePipe = getOrCreateMessagePipe();
 
         boolean hasCaughtUpWithOldMessages = false;
 
@@ -1742,18 +1683,11 @@ public class Manager implements Closeable {
             SignalServiceEnvelope envelope;
             SignalServiceContent content = null;
             Exception exception = null;
-            final long now = new Date().getTime();
+            final CachedMessage[] cachedMessage = {null};
             try {
                 Optional<SignalServiceEnvelope> result = messagePipe.readOrEmpty(timeout, unit, envelope1 -> {
                     // store message on disk, before acknowledging receipt to the server
-                    try {
-                        String source = envelope1.getSourceE164().isPresent() ? envelope1.getSourceE164().get() : "";
-                        File cacheFile = getMessageCacheFile(source, now, envelope1.getTimestamp());
-                        Utils.storeEnvelope(envelope1, cacheFile);
-                    } catch (IOException e) {
-                        System.err.println("Failed to store encrypted message in disk cache, ignoring: "
-                                + e.getMessage());
-                    }
+                    cachedMessage[0] = account.getMessageCache().cacheMessage(envelope1);
                 });
                 if (result.isPresent()) {
                     envelope = result.get();
@@ -1766,7 +1700,7 @@ public class Manager implements Closeable {
                             try {
                                 action.execute(this);
                             } catch (Throwable e) {
-                                e.printStackTrace();
+                                logger.warn("Message action failed.", e);
                             }
                         }
                         account.save();
@@ -1781,7 +1715,7 @@ public class Manager implements Closeable {
                 if (returnOnTimeout) return;
                 continue;
             } catch (InvalidVersionException e) {
-                System.err.println("Ignoring error: " + e.getMessage());
+                logger.warn("Error while receiving messages, ignoring: {}", e.getMessage());
                 continue;
             }
 
@@ -1802,7 +1736,7 @@ public class Manager implements Closeable {
                         try {
                             action.execute(this);
                         } catch (Throwable e) {
-                            e.printStackTrace();
+                            logger.warn("Message action failed.", e);
                         }
                     }
                 } else {
@@ -1813,19 +1747,16 @@ public class Manager implements Closeable {
                 }
             }
             account.save();
-            if (!isMessageBlocked(envelope, content)) {
+            if (isMessageBlocked(envelope, content)) {
+                logger.info("Ignoring a message from blocked user/group: {}", envelope.getTimestamp());
+            } else if (isNotAGroupMember(envelope, content)) {
+                logger.info("Ignoring a message from a non group member: {}", envelope.getTimestamp());
+            } else {
                 handler.handleMessage(envelope, content, exception);
             }
             if (!(exception instanceof org.whispersystems.libsignal.UntrustedIdentityException)) {
-                File cacheFile = null;
-                try {
-                    String source = envelope.getSourceE164().isPresent() ? envelope.getSourceE164().get() : "";
-                    cacheFile = getMessageCacheFile(source, now, envelope.getTimestamp());
-                    Files.delete(cacheFile.toPath());
-                    // Try to delete directory if empty
-                    new File(getMessageCachePath()).delete();
-                } catch (IOException e) {
-                    System.err.println("Failed to delete cached message file “" + cacheFile + "”: " + e.getMessage());
+                if (cachedMessage[0] != null) {
+                    cachedMessage[0].delete();
                 }
             }
         }
@@ -1849,10 +1780,43 @@ public class Manager implements Closeable {
 
         if (content != null && content.getDataMessage().isPresent()) {
             SignalServiceDataMessage message = content.getDataMessage().get();
-            if (message.getGroupContext().isPresent() && message.getGroupContext().get().getGroupV1().isPresent()) {
-                SignalServiceGroup groupInfo = message.getGroupContext().get().getGroupV1().get();
-                GroupInfo group = getGroup(groupInfo.getGroupId());
-                return groupInfo.getType() == SignalServiceGroup.Type.DELIVER && group != null && group.isBlocked();
+            if (message.getGroupContext().isPresent()) {
+                GroupId groupId = GroupUtils.getGroupId(message.getGroupContext().get());
+                GroupInfo group = getGroup(groupId);
+                if (group != null && group.isBlocked()) {
+                    return true;
+                }
+            }
+        }
+        return false;
+    }
+
+    private boolean isNotAGroupMember(
+            SignalServiceEnvelope envelope, SignalServiceContent content
+    ) {
+        SignalServiceAddress source;
+        if (!envelope.isUnidentifiedSender() && envelope.hasSource()) {
+            source = envelope.getSourceAddress();
+        } else if (content != null) {
+            source = content.getSender();
+        } else {
+            return false;
+        }
+
+        if (content != null && content.getDataMessage().isPresent()) {
+            SignalServiceDataMessage message = content.getDataMessage().get();
+            if (message.getGroupContext().isPresent()) {
+                if (message.getGroupContext().get().getGroupV1().isPresent()) {
+                    SignalServiceGroup groupInfo = message.getGroupContext().get().getGroupV1().get();
+                    if (groupInfo.getType() == SignalServiceGroup.Type.QUIT) {
+                        return false;
+                    }
+                }
+                GroupId groupId = GroupUtils.getGroupId(message.getGroupContext().get());
+                GroupInfo group = getGroup(groupId);
+                if (group != null && !group.isMember(source)) {
+                    return true;
+                }
             }
         }
         return false;
@@ -1863,7 +1827,7 @@ public class Manager implements Closeable {
     ) {
         List<HandleAction> actions = new ArrayList<>();
         if (content != null) {
-            SignalServiceAddress sender;
+            final SignalServiceAddress sender;
             if (!envelope.isUnidentifiedSender() && envelope.hasSource()) {
                 sender = envelope.getSourceAddress();
             } else {
@@ -1890,10 +1854,11 @@ public class Manager implements Closeable {
                 SignalServiceSyncMessage syncMessage = content.getSyncMessage().get();
                 if (syncMessage.getSent().isPresent()) {
                     SentTranscriptMessage message = syncMessage.getSent().get();
+                    final SignalServiceAddress destination = message.getDestination().orNull();
                     actions.addAll(handleSignalServiceDataMessage(message.getMessage(),
                             true,
                             sender,
-                            message.getDestination().orNull(),
+                            destination,
                             ignoreAttachments));
                 }
                 if (syncMessage.getRequest().isPresent()) {
@@ -1913,13 +1878,14 @@ public class Manager implements Closeable {
                     File tmpFile = null;
                     try {
                         tmpFile = IOUtils.createTempFile();
-                        try (InputStream attachmentAsStream = retrieveAttachmentAsStream(syncMessage.getGroups()
-                                .get()
-                                .asPointer(), tmpFile)) {
+                        final SignalServiceAttachment groupsMessage = syncMessage.getGroups().get();
+                        try (InputStream attachmentAsStream = retrieveAttachmentAsStream(groupsMessage.asPointer(),
+                                tmpFile)) {
                             DeviceGroupsInputStream s = new DeviceGroupsInputStream(attachmentAsStream);
                             DeviceGroup g;
                             while ((g = s.read()) != null) {
-                                GroupInfoV1 syncGroup = account.getGroupStore().getOrCreateGroupV1(g.getId());
+                                GroupInfoV1 syncGroup = account.getGroupStore()
+                                        .getOrCreateGroupV1(GroupId.v1(g.getId()));
                                 if (syncGroup != null) {
                                     if (g.getName().isPresent()) {
                                         syncGroup.name = g.getName().get();
@@ -1932,7 +1898,7 @@ public class Manager implements Closeable {
                                         syncGroup.removeMember(account.getSelfAddress());
                                     } else {
                                         // Add ourself to the member set as it's marked as active
-                                        syncGroup.addMembers(Collections.singleton(account.getSelfAddress()));
+                                        syncGroup.addMembers(List.of(account.getSelfAddress()));
                                     }
                                     syncGroup.blocked = g.isBlocked();
                                     if (g.getColor().isPresent()) {
@@ -1940,7 +1906,7 @@ public class Manager implements Closeable {
                                     }
 
                                     if (g.getAvatar().isPresent()) {
-                                        retrieveGroupAvatarAttachment(g.getAvatar().get(), syncGroup.groupId);
+                                        downloadGroupAvatar(g.getAvatar().get(), syncGroup.getGroupId());
                                     }
                                     syncGroup.inboxPosition = g.getInboxPosition().orNull();
                                     syncGroup.archived = g.isArchived();
@@ -1949,16 +1915,17 @@ public class Manager implements Closeable {
                             }
                         }
                     } catch (Exception e) {
-                        e.printStackTrace();
+                        logger.warn("Failed to handle received sync groups “{}”, ignoring: {}",
+                                tmpFile,
+                                e.getMessage());
                     } finally {
                         if (tmpFile != null) {
                             try {
                                 Files.delete(tmpFile.toPath());
                             } catch (IOException e) {
-                                System.err.println("Failed to delete received groups temp file “"
-                                        + tmpFile
-                                        + "”: "
-                                        + e.getMessage());
+                                logger.warn("Failed to delete received groups temp file “{}”, ignoring: {}",
+                                        tmpFile,
+                                        e.getMessage());
                             }
                         }
                     }
@@ -1968,12 +1935,15 @@ public class Manager implements Closeable {
                     for (SignalServiceAddress address : blockedListMessage.getAddresses()) {
                         setContactBlocked(resolveSignalServiceAddress(address), true);
                     }
-                    for (byte[] groupId : blockedListMessage.getGroupIds()) {
+                    for (GroupId groupId : blockedListMessage.getGroupIds()
+                            .stream()
+                            .map(GroupId::unknownVersion)
+                            .collect(Collectors.toSet())) {
                         try {
                             setGroupBlocked(groupId, true);
                         } catch (GroupNotFoundException e) {
-                            System.err.println("BlockedListMessage contained groupID that was not found in GroupStore: "
-                                    + Base64.encodeBytes(groupId));
+                            logger.warn("BlockedListMessage contained groupID that was not found in GroupStore: {}",
+                                    groupId.toBase64());
                         }
                     }
                 }
@@ -2023,21 +1993,22 @@ public class Manager implements Closeable {
                                 account.getContactStore().updateContact(contact);
 
                                 if (c.getAvatar().isPresent()) {
-                                    retrieveContactAvatarAttachment(c.getAvatar().get(), contact.number);
+                                    downloadContactAvatar(c.getAvatar().get(), contact.getAddress());
                                 }
                             }
                         }
                     } catch (Exception e) {
-                        e.printStackTrace();
+                        logger.warn("Failed to handle received sync contacts “{}”, ignoring: {}",
+                                tmpFile,
+                                e.getMessage());
                     } finally {
                         if (tmpFile != null) {
                             try {
                                 Files.delete(tmpFile.toPath());
                             } catch (IOException e) {
-                                System.err.println("Failed to delete received contacts temp file “"
-                                        + tmpFile
-                                        + "”: "
-                                        + e.getMessage());
+                                logger.warn("Failed to delete received contacts temp file “{}”, ignoring: {}",
+                                        tmpFile,
+                                        e.getMessage());
                             }
                         }
                     }
@@ -2068,6 +2039,21 @@ public class Manager implements Closeable {
                         account.getStickerStore().updateSticker(sticker);
                     }
                 }
+                if (syncMessage.getFetchType().isPresent()) {
+                    switch (syncMessage.getFetchType().get()) {
+                        case LOCAL_PROFILE:
+                            getRecipientProfile(getSelfAddress(), true);
+                        case STORAGE_MANIFEST:
+                            // TODO
+                    }
+                }
+                if (syncMessage.getKeys().isPresent()) {
+                    final KeysMessage keysMessage = syncMessage.getKeys().get();
+                    if (keysMessage.getStorageService().isPresent()) {
+                        final StorageKey storageKey = keysMessage.getStorageService().get();
+                        account.setStorageKey(storageKey);
+                    }
+                }
                 if (syncMessage.getConfiguration().isPresent()) {
                     // TODO
                 }
@@ -2076,115 +2062,149 @@ public class Manager implements Closeable {
         return actions;
     }
 
-    private File getContactAvatarFile(String number) {
-        return new File(pathConfig.getAvatarsPath(), "contact-" + number);
+    private void downloadContactAvatar(SignalServiceAttachment avatar, SignalServiceAddress address) {
+        try {
+            avatarStore.storeContactAvatar(address, outputStream -> retrieveAttachment(avatar, outputStream));
+        } catch (IOException e) {
+            logger.warn("Failed to download avatar for contact {}, ignoring: {}", address, e.getMessage());
+        }
     }
 
-    private File retrieveContactAvatarAttachment(
-            SignalServiceAttachment attachment, String number
-    ) throws IOException, InvalidMessageException, MissingConfigurationException {
-        IOUtils.createPrivateDirectories(pathConfig.getAvatarsPath());
-        if (attachment.isPointer()) {
-            SignalServiceAttachmentPointer pointer = attachment.asPointer();
-            return retrieveAttachment(pointer, getContactAvatarFile(number), false);
-        } else {
-            SignalServiceAttachmentStream stream = attachment.asStream();
-            return Utils.retrieveAttachment(stream, getContactAvatarFile(number));
+    private void downloadGroupAvatar(SignalServiceAttachment avatar, GroupId groupId) {
+        try {
+            avatarStore.storeGroupAvatar(groupId, outputStream -> retrieveAttachment(avatar, outputStream));
+        } catch (IOException e) {
+            logger.warn("Failed to download avatar for group {}, ignoring: {}", groupId.toBase64(), e.getMessage());
         }
     }
 
-    private File getGroupAvatarFile(byte[] groupId) {
-        return new File(pathConfig.getAvatarsPath(), "group-" + Base64.encodeBytes(groupId).replace("/", "_"));
+    private void downloadGroupAvatar(GroupId groupId, GroupSecretParams groupSecretParams, String cdnKey) {
+        try {
+            avatarStore.storeGroupAvatar(groupId,
+                    outputStream -> retrieveGroupV2Avatar(groupSecretParams, cdnKey, outputStream));
+        } catch (IOException e) {
+            logger.warn("Failed to download avatar for group {}, ignoring: {}", groupId.toBase64(), e.getMessage());
+        }
     }
 
-    private File retrieveGroupAvatarAttachment(
-            SignalServiceAttachment attachment, byte[] groupId
-    ) throws IOException, InvalidMessageException, MissingConfigurationException {
-        IOUtils.createPrivateDirectories(pathConfig.getAvatarsPath());
-        if (attachment.isPointer()) {
-            SignalServiceAttachmentPointer pointer = attachment.asPointer();
-            return retrieveAttachment(pointer, getGroupAvatarFile(groupId), false);
-        } else {
-            SignalServiceAttachmentStream stream = attachment.asStream();
-            return Utils.retrieveAttachment(stream, getGroupAvatarFile(groupId));
+    private void downloadProfileAvatar(
+            SignalServiceAddress address, String avatarPath, ProfileKey profileKey
+    ) {
+        try {
+            avatarStore.storeProfileAvatar(address,
+                    outputStream -> retrieveProfileAvatar(avatarPath, profileKey, outputStream));
+        } catch (Throwable e) {
+            logger.warn("Failed to download profile avatar, ignoring: {}", e.getMessage());
         }
     }
 
-    private File getProfileAvatarFile(SignalServiceAddress address) {
-        return new File(pathConfig.getAvatarsPath(), "profile-" + address.getLegacyIdentifier());
+    public File getAttachmentFile(SignalServiceAttachmentRemoteId attachmentId) {
+        return attachmentStore.getAttachmentFile(attachmentId);
     }
 
-    private File retrieveProfileAvatar(
-            SignalServiceAddress address, String avatarPath, ProfileKey profileKey
+    private void downloadAttachment(final SignalServiceAttachment attachment) {
+        if (!attachment.isPointer()) {
+            logger.warn("Invalid state, can't store an attachment stream.");
+        }
+
+        SignalServiceAttachmentPointer pointer = attachment.asPointer();
+        if (pointer.getPreview().isPresent()) {
+            final byte[] preview = pointer.getPreview().get();
+            try {
+                attachmentStore.storeAttachmentPreview(pointer.getRemoteId(),
+                        outputStream -> outputStream.write(preview, 0, preview.length));
+            } catch (IOException e) {
+                logger.warn("Failed to download attachment preview, ignoring: {}", e.getMessage());
+            }
+        }
+
+        try {
+            attachmentStore.storeAttachment(pointer.getRemoteId(),
+                    outputStream -> retrieveAttachmentPointer(pointer, outputStream));
+        } catch (IOException e) {
+            logger.warn("Failed to download attachment ({}), ignoring: {}", pointer.getRemoteId(), e.getMessage());
+        }
+    }
+
+    private void retrieveGroupV2Avatar(
+            GroupSecretParams groupSecretParams, String cdnKey, OutputStream outputStream
     ) throws IOException {
-        IOUtils.createPrivateDirectories(pathConfig.getAvatarsPath());
-        SignalServiceMessageReceiver receiver = getOrCreateMessageReceiver();
-        File outputFile = getProfileAvatarFile(address);
+        GroupsV2Operations.GroupOperations groupOperations = groupsV2Operations.forGroup(groupSecretParams);
 
         File tmpFile = IOUtils.createTempFile();
-        try (InputStream input = receiver.retrieveProfileAvatar(avatarPath,
+        try (InputStream input = messageReceiver.retrieveGroupsV2ProfileAvatar(cdnKey,
                 tmpFile,
-                profileKey,
                 ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE)) {
-            // Use larger buffer size to prevent AssertionError: Need: 12272 but only have: 8192 ...
-            IOUtils.copyStreamToFile(input, outputFile, (int) ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE);
+            byte[] encryptedData = IOUtils.readFully(input);
+
+            byte[] decryptedData = groupOperations.decryptAvatar(encryptedData);
+            outputStream.write(decryptedData);
         } finally {
             try {
                 Files.delete(tmpFile.toPath());
             } catch (IOException e) {
-                System.err.println("Failed to delete received avatar temp file “" + tmpFile + "”: " + e.getMessage());
+                logger.warn("Failed to delete received group avatar temp file “{}”, ignoring: {}",
+                        tmpFile,
+                        e.getMessage());
             }
         }
-        return outputFile;
-    }
-
-    public File getAttachmentFile(SignalServiceAttachmentRemoteId attachmentId) {
-        return new File(pathConfig.getAttachmentsPath(), attachmentId.toString());
-    }
-
-    private File retrieveAttachment(SignalServiceAttachmentPointer pointer) throws IOException, InvalidMessageException, MissingConfigurationException {
-        IOUtils.createPrivateDirectories(pathConfig.getAttachmentsPath());
-        return retrieveAttachment(pointer, getAttachmentFile(pointer.getRemoteId()), true);
     }
 
-    private File retrieveAttachment(
-            SignalServiceAttachmentPointer pointer, File outputFile, boolean storePreview
-    ) throws IOException, InvalidMessageException, MissingConfigurationException {
-        if (storePreview && pointer.getPreview().isPresent()) {
-            File previewFile = new File(outputFile + ".preview");
-            try (OutputStream output = new FileOutputStream(previewFile)) {
-                byte[] preview = pointer.getPreview().get();
-                output.write(preview, 0, preview.length);
-            } catch (FileNotFoundException e) {
-                e.printStackTrace();
-                return null;
+    private void retrieveProfileAvatar(
+            String avatarPath, ProfileKey profileKey, OutputStream outputStream
+    ) throws IOException {
+        File tmpFile = IOUtils.createTempFile();
+        try (InputStream input = messageReceiver.retrieveProfileAvatar(avatarPath,
+                tmpFile,
+                profileKey,
+                ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE)) {
+            // Use larger buffer size to prevent AssertionError: Need: 12272 but only have: 8192 ...
+            IOUtils.copyStream(input, outputStream, (int) ServiceConfig.AVATAR_DOWNLOAD_FAILSAFE_MAX_SIZE);
+        } finally {
+            try {
+                Files.delete(tmpFile.toPath());
+            } catch (IOException e) {
+                logger.warn("Failed to delete received profile avatar temp file “{}”, ignoring: {}",
+                        tmpFile,
+                        e.getMessage());
             }
         }
+    }
 
-        final SignalServiceMessageReceiver messageReceiver = getOrCreateMessageReceiver();
+    private void retrieveAttachment(
+            final SignalServiceAttachment attachment, final OutputStream outputStream
+    ) throws IOException {
+        if (attachment.isPointer()) {
+            SignalServiceAttachmentPointer pointer = attachment.asPointer();
+            retrieveAttachmentPointer(pointer, outputStream);
+        } else {
+            SignalServiceAttachmentStream stream = attachment.asStream();
+            IOUtils.copyStream(stream.getInputStream(), outputStream);
+        }
+    }
 
+    private void retrieveAttachmentPointer(
+            SignalServiceAttachmentPointer pointer, OutputStream outputStream
+    ) throws IOException {
         File tmpFile = IOUtils.createTempFile();
-        try (InputStream input = messageReceiver.retrieveAttachment(pointer,
-                tmpFile,
-                ServiceConfig.MAX_ATTACHMENT_SIZE)) {
-            IOUtils.copyStreamToFile(input, outputFile);
+        try (InputStream input = retrieveAttachmentAsStream(pointer, tmpFile)) {
+            IOUtils.copyStream(input, outputStream);
+        } catch (MissingConfigurationException | InvalidMessageException e) {
+            throw new IOException(e);
         } finally {
             try {
                 Files.delete(tmpFile.toPath());
             } catch (IOException e) {
-                System.err.println("Failed to delete received attachment temp file “"
-                        + tmpFile
-                        + "”: "
-                        + e.getMessage());
+                logger.warn("Failed to delete received attachment temp file “{}”, ignoring: {}",
+                        tmpFile,
+                        e.getMessage());
             }
         }
-        return outputFile;
     }
 
     private InputStream retrieveAttachmentAsStream(
             SignalServiceAttachmentPointer pointer, File tmpFile
     ) throws IOException, InvalidMessageException, MissingConfigurationException {
-        final SignalServiceMessageReceiver messageReceiver = getOrCreateMessageReceiver();
         return messageReceiver.retrieveAttachment(pointer, tmpFile, ServiceConfig.MAX_ATTACHMENT_SIZE);
     }
 
@@ -2194,13 +2214,13 @@ public class Manager implements Closeable {
         try {
             try (OutputStream fos = new FileOutputStream(groupsFile)) {
                 DeviceGroupsOutputStream out = new DeviceGroupsOutputStream(fos);
-                for (GroupInfo record : account.getGroupStore().getGroups()) {
+                for (GroupInfo record : getGroups()) {
                     if (record instanceof GroupInfoV1) {
                         GroupInfoV1 groupInfo = (GroupInfoV1) record;
-                        out.write(new DeviceGroup(groupInfo.groupId,
+                        out.write(new DeviceGroup(groupInfo.getGroupId().serialize(),
                                 Optional.fromNullable(groupInfo.name),
                                 new ArrayList<>(groupInfo.getMembers()),
-                                createGroupAvatarAttachment(groupInfo.groupId),
+                                createGroupAvatarAttachment(groupInfo.getGroupId()),
                                 groupInfo.isMember(account.getSelfAddress()),
                                 Optional.of(groupInfo.messageExpirationTime),
                                 Optional.fromNullable(groupInfo.color),
@@ -2226,7 +2246,7 @@ public class Manager implements Closeable {
             try {
                 Files.delete(groupsFile.toPath());
             } catch (IOException e) {
-                System.err.println("Failed to delete groups temp file “" + groupsFile + "”: " + e.getMessage());
+                logger.warn("Failed to delete groups temp file “{}”, ignoring: {}", groupsFile, e.getMessage());
             }
         }
     }
@@ -2239,8 +2259,7 @@ public class Manager implements Closeable {
                 DeviceContactsOutputStream out = new DeviceContactsOutputStream(fos);
                 for (ContactInfo record : account.getContactStore().getContacts()) {
                     VerifiedMessage verifiedMessage = null;
-                    JsonIdentityKeyStore.Identity currentIdentity = account.getSignalProtocolStore()
-                            .getIdentity(record.getAddress());
+                    IdentityInfo currentIdentity = account.getSignalProtocolStore().getIdentity(record.getAddress());
                     if (currentIdentity != null) {
                         verifiedMessage = new VerifiedMessage(record.getAddress(),
                                 currentIdentity.getIdentityKey(),
@@ -2251,7 +2270,7 @@ public class Manager implements Closeable {
                     ProfileKey profileKey = account.getProfileStore().getProfileKey(record.getAddress());
                     out.write(new DeviceContact(record.getAddress(),
                             Optional.fromNullable(record.name),
-                            createContactAvatarAttachment(record.number),
+                            createContactAvatarAttachment(record.getAddress()),
                             Optional.fromNullable(record.color),
                             Optional.fromNullable(verifiedMessage),
                             Optional.fromNullable(profileKey),
@@ -2291,7 +2310,7 @@ public class Manager implements Closeable {
             try {
                 Files.delete(contactsFile.toPath());
             } catch (IOException e) {
-                System.err.println("Failed to delete contacts temp file “" + contactsFile + "”: " + e.getMessage());
+                logger.warn("Failed to delete contacts temp file “{}”, ignoring: {}", contactsFile, e.getMessage());
             }
         }
     }
@@ -2304,9 +2323,9 @@ public class Manager implements Closeable {
             }
         }
         List<byte[]> groupIds = new ArrayList<>();
-        for (GroupInfo record : account.getGroupStore().getGroups()) {
+        for (GroupInfo record : getGroups()) {
             if (record.isBlocked()) {
-                groupIds.add(record.groupId);
+                groupIds.add(record.getGroupId().serialize());
             }
         }
         sendSyncMessage(SignalServiceSyncMessage.forBlocked(new BlockedListMessage(addresses, groupIds)));
@@ -2326,19 +2345,37 @@ public class Manager implements Closeable {
         return account.getContactStore().getContacts();
     }
 
-    public ContactInfo getContact(String number) {
-        return account.getContactStore().getContact(Util.getSignalServiceAddressFromIdentifier(number));
+    public String getContactOrProfileName(String number) {
+        final SignalServiceAddress address = Utils.getSignalServiceAddressFromIdentifier(number);
+
+        final ContactInfo contact = account.getContactStore().getContact(address);
+        if (contact != null && !Util.isEmpty(contact.name)) {
+            return contact.name;
+        }
+
+        final SignalProfileEntry profileEntry = account.getProfileStore().getProfileEntry(address);
+        if (profileEntry != null && profileEntry.getProfile() != null) {
+            return profileEntry.getProfile().getName();
+        }
+
+        return null;
     }
 
-    public GroupInfo getGroup(byte[] groupId) {
-        return account.getGroupStore().getGroup(groupId);
+    public GroupInfo getGroup(GroupId groupId) {
+        final GroupInfo group = account.getGroupStore().getGroup(groupId);
+        if (group instanceof GroupInfoV2 && ((GroupInfoV2) group).getGroup() == null) {
+            final GroupSecretParams groupSecretParams = GroupSecretParams.deriveFromMasterKey(((GroupInfoV2) group).getMasterKey());
+            ((GroupInfoV2) group).setGroup(groupHelper.getDecryptedGroup(groupSecretParams));
+            account.getGroupStore().updateGroup(group);
+        }
+        return group;
     }
 
-    public List<JsonIdentityKeyStore.Identity> getIdentities() {
+    public List<IdentityInfo> getIdentities() {
         return account.getSignalProtocolStore().getIdentities();
     }
 
-    public List<JsonIdentityKeyStore.Identity> getIdentities(String number) throws InvalidNumberException {
+    public List<IdentityInfo> getIdentities(String number) throws InvalidNumberException {
         return account.getSignalProtocolStore().getIdentities(canonicalizeAndResolveSignalServiceAddress(number));
     }
 
@@ -2350,11 +2387,11 @@ public class Manager implements Closeable {
      */
     public boolean trustIdentityVerified(String name, byte[] fingerprint) throws InvalidNumberException {
         SignalServiceAddress address = canonicalizeAndResolveSignalServiceAddress(name);
-        List<JsonIdentityKeyStore.Identity> ids = account.getSignalProtocolStore().getIdentities(address);
+        List<IdentityInfo> ids = account.getSignalProtocolStore().getIdentities(address);
         if (ids == null) {
             return false;
         }
-        for (JsonIdentityKeyStore.Identity id : ids) {
+        for (IdentityInfo id : ids) {
             if (!Arrays.equals(id.getIdentityKey().serialize(), fingerprint)) {
                 continue;
             }
@@ -2364,7 +2401,7 @@ public class Manager implements Closeable {
             try {
                 sendVerifiedMessage(address, id.getIdentityKey(), TrustLevel.TRUSTED_VERIFIED);
             } catch (IOException | UntrustedIdentityException e) {
-                e.printStackTrace();
+                logger.warn("Failed to send verification sync message: {}", e.getMessage());
             }
             account.save();
             return true;
@@ -2380,11 +2417,11 @@ public class Manager implements Closeable {
      */
     public boolean trustIdentityVerifiedSafetyNumber(String name, String safetyNumber) throws InvalidNumberException {
         SignalServiceAddress address = canonicalizeAndResolveSignalServiceAddress(name);
-        List<JsonIdentityKeyStore.Identity> ids = account.getSignalProtocolStore().getIdentities(address);
+        List<IdentityInfo> ids = account.getSignalProtocolStore().getIdentities(address);
         if (ids == null) {
             return false;
         }
-        for (JsonIdentityKeyStore.Identity id : ids) {
+        for (IdentityInfo id : ids) {
             if (!safetyNumber.equals(computeSafetyNumber(address, id.getIdentityKey()))) {
                 continue;
             }
@@ -2394,7 +2431,7 @@ public class Manager implements Closeable {
             try {
                 sendVerifiedMessage(address, id.getIdentityKey(), TrustLevel.TRUSTED_VERIFIED);
             } catch (IOException | UntrustedIdentityException e) {
-                e.printStackTrace();
+                logger.warn("Failed to send verification sync message: {}", e.getMessage());
             }
             account.save();
             return true;
@@ -2409,18 +2446,18 @@ public class Manager implements Closeable {
      */
     public boolean trustIdentityAllKeys(String name) {
         SignalServiceAddress address = resolveSignalServiceAddress(name);
-        List<JsonIdentityKeyStore.Identity> ids = account.getSignalProtocolStore().getIdentities(address);
+        List<IdentityInfo> ids = account.getSignalProtocolStore().getIdentities(address);
         if (ids == null) {
             return false;
         }
-        for (JsonIdentityKeyStore.Identity id : ids) {
+        for (IdentityInfo id : ids) {
             if (id.getTrustLevel() == TrustLevel.UNTRUSTED) {
                 account.getSignalProtocolStore()
                         .setIdentityTrustLevel(address, id.getIdentityKey(), TrustLevel.TRUSTED_UNVERIFIED);
                 try {
                     sendVerifiedMessage(address, id.getIdentityKey(), TrustLevel.TRUSTED_UNVERIFIED);
                 } catch (IOException | UntrustedIdentityException e) {
-                    e.printStackTrace();
+                    logger.warn("Failed to send verification sync message: {}", e.getMessage());
                 }
             }
         }
@@ -2431,25 +2468,22 @@ public class Manager implements Closeable {
     public String computeSafetyNumber(
             SignalServiceAddress theirAddress, IdentityKey theirIdentityKey
     ) {
-        return Utils.computeSafetyNumber(account.getSelfAddress(),
+        return Utils.computeSafetyNumber(ServiceConfig.capabilities.isUuid(),
+                account.getSelfAddress(),
                 getIdentityKeyPair().getPublicKey(),
                 theirAddress,
                 theirIdentityKey);
     }
 
-    void saveAccount() {
-        account.save();
-    }
-
     public SignalServiceAddress canonicalizeAndResolveSignalServiceAddress(String identifier) throws InvalidNumberException {
         String canonicalizedNumber = UuidUtil.isUuid(identifier)
                 ? identifier
-                : Util.canonicalizeNumber(identifier, account.getUsername());
+                : PhoneNumberFormatter.formatNumber(identifier, account.getUsername());
         return resolveSignalServiceAddress(canonicalizedNumber);
     }
 
     public SignalServiceAddress resolveSignalServiceAddress(String identifier) {
-        SignalServiceAddress address = Util.getSignalServiceAddressFromIdentifier(identifier);
+        SignalServiceAddress address = Utils.getSignalServiceAddressFromIdentifier(identifier);
 
         return resolveSignalServiceAddress(address);
     }
@@ -2464,6 +2498,10 @@ public class Manager implements Closeable {
 
     @Override
     public void close() throws IOException {
+        close(true);
+    }
+
+    void close(boolean closeAccount) throws IOException {
         if (messagePipe != null) {
             messagePipe.shutdown();
             messagePipe = null;
@@ -2474,7 +2512,10 @@ public class Manager implements Closeable {
             unidentifiedMessagePipe = null;
         }
 
-        account.close();
+        if (closeAccount && account != null) {
+            account.close();
+        }
+        account = null;
     }
 
     public interface ReceiveMessageHandler {