WIP backup & restore

2019-01-22 19:25:45 +01:00 · 2019-01-22 19:25:45 +01:00 · c9fc40dfe5
parent 68565f2766
commit c9fc40dfe5
39 changed files with 1684 additions and 754 deletions
--- a/src/conversations/AndroidManifest.xml
+++ b/src/conversations/AndroidManifest.xml
@ -16,6 +16,10 @@
            android:name=".ui.MagicCreateActivity"
            android:label="@string/create_account"
            android:launchMode="singleTask"/>
+        <activity
+            android:name=".ui.ImportBackupActivity"
+            android:label="@string/restore_backup"
+            android:launchMode="singleTask" />

    </application>
 </manifest>
--- a/src/conversations/java/eu/siacs/conversations/services/ImportBackupService.java
+++ b/src/conversations/java/eu/siacs/conversations/services/ImportBackupService.java
@ -0,0 +1,276 @@
+package eu.siacs.conversations.services;
+
+import android.app.NotificationManager;
+import android.app.PendingIntent;
+import android.app.Service;
+import android.content.Context;
+import android.content.Intent;
+import android.database.sqlite.SQLiteDatabase;
+import android.os.Binder;
+import android.os.IBinder;
+import android.support.v4.app.NotificationCompat;
+import android.util.Log;
+
+import java.io.BufferedReader;
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.WeakHashMap;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.zip.GZIPInputStream;
+
+import javax.crypto.AEADBadTagException;
+import javax.crypto.BadPaddingException;
+import javax.crypto.Cipher;
+import javax.crypto.CipherInputStream;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.SecretKeySpec;
+
+import eu.siacs.conversations.Config;
+import eu.siacs.conversations.R;
+import eu.siacs.conversations.persistance.DatabaseBackend;
+import eu.siacs.conversations.persistance.FileBackend;
+import eu.siacs.conversations.ui.ManageAccountActivity;
+import eu.siacs.conversations.utils.BackupFileHeader;
+import eu.siacs.conversations.utils.Compatibility;
+import eu.siacs.conversations.utils.SerialSingleThreadExecutor;
+
+import static eu.siacs.conversations.services.ExportBackupService.CIPHERMODE;
+import static eu.siacs.conversations.services.ExportBackupService.KEYTYPE;
+import static eu.siacs.conversations.services.ExportBackupService.PROVIDER;
+
+public class ImportBackupService extends Service {
+
+    private static final int NOTIFICATION_ID = 21;
+
+    private final ImportBackupServiceBinder binder = new ImportBackupServiceBinder();
+    private final SerialSingleThreadExecutor executor = new SerialSingleThreadExecutor(getClass().getSimpleName());
+
+    private final Set<OnBackupProcessed> mOnBackupProcessedListeners = Collections.newSetFromMap(new WeakHashMap<>());
+
+    private static AtomicBoolean running = new AtomicBoolean(false);
+    private DatabaseBackend mDatabaseBackend;
+    private NotificationManager notificationManager;
+
+    private static int count(String input, char c) {
+        int count = 0;
+        for (char aChar : input.toCharArray()) {
+            if (aChar == c) {
+                ++count;
+            }
+        }
+        return count;
+    }
+
+    @Override
+    public void onCreate() {
+        mDatabaseBackend = DatabaseBackend.getInstance(getBaseContext());
+        notificationManager = (android.app.NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
+    }
+
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+        if (intent == null) {
+            return START_NOT_STICKY;
+        }
+        final String password = intent.getStringExtra("password");
+        final String file = intent.getStringExtra("file");
+        if (password == null || file == null) {
+            return START_NOT_STICKY;
+        }
+        Log.d(Config.LOGTAG, "on start command");
+        if (running.compareAndSet(false, true)) {
+            executor.execute(() -> {
+                startForegroundService();
+                final boolean success = importBackup(new File(file), password);
+                stopForeground(true);
+                running.set(false);
+                if (success) {
+                    notifySuccess();
+                }
+                stopSelf();
+            });
+        } else {
+            Log.d(Config.LOGTAG, "backup already running");
+        }
+        return START_NOT_STICKY;
+    }
+
+    public void loadBackupFiles(OnBackupFilesLoaded onBackupFilesLoaded) {
+        executor.execute(() -> {
+            final ArrayList<BackupFile> backupFiles = new ArrayList<>();
+            for (String app : Arrays.asList("Conversations", "Quicksy")) {
+                final File directory = new File(FileBackend.getBackupDirectory(app));
+                if (!directory.exists() || !directory.isDirectory()) {
+                    Log.d(Config.LOGTAG, "directory not found: " + directory.getAbsolutePath());
+                    continue;
+                }
+                for (File file : directory.listFiles()) {
+                    if (file.isFile() && file.getName().endsWith(".ceb")) {
+                        try {
+                            backupFiles.add(BackupFile.read(file));
+                        } catch (IOException e) {
+                            Log.d(Config.LOGTAG, "unable to read backup file ", e);
+                        }
+                    }
+                }
+            }
+            onBackupFilesLoaded.onBackupFilesLoaded(backupFiles);
+        });
+    }
+
+    private void startForegroundService() {
+        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getBaseContext(), "backup");
+        mBuilder.setContentTitle(getString(R.string.notification_restore_backup_title))
+                .setSmallIcon(R.drawable.ic_unarchive_white_24dp)
+                .setProgress(1, 0, true);
+        startForeground(NOTIFICATION_ID, mBuilder.build());
+    }
+
+    private boolean importBackup(File file, String password) {
+        Log.d(Config.LOGTAG, "importing backup from file " + file.getAbsolutePath());
+        try {
+            SQLiteDatabase db = mDatabaseBackend.getWritableDatabase();
+            final FileInputStream fileInputStream = new FileInputStream(file);
+            final DataInputStream dataInputStream = new DataInputStream(fileInputStream);
+            BackupFileHeader backupFileHeader = BackupFileHeader.read(dataInputStream);
+            Log.d(Config.LOGTAG, backupFileHeader.toString());
+
+            final Cipher cipher = Compatibility.twentyEight() ? Cipher.getInstance(CIPHERMODE) : Cipher.getInstance(CIPHERMODE, PROVIDER);
+            byte[] key = ExportBackupService.getKey(password, backupFileHeader.getSalt());
+            SecretKeySpec keySpec = new SecretKeySpec(key, KEYTYPE);
+            IvParameterSpec ivSpec = new IvParameterSpec(backupFileHeader.getIv());
+            cipher.init(Cipher.DECRYPT_MODE, keySpec, ivSpec);
+            CipherInputStream cipherInputStream = new CipherInputStream(fileInputStream, cipher);
+
+            GZIPInputStream gzipInputStream = new GZIPInputStream(cipherInputStream);
+            BufferedReader reader = new BufferedReader(new InputStreamReader(gzipInputStream, "UTF-8"));
+            String line;
+            StringBuilder multiLineQuery = null;
+            while ((line = reader.readLine()) != null) {
+                int count = count(line, '\'');
+                if (multiLineQuery != null) {
+                    multiLineQuery.append(line);
+                    if (count % 2 == 1) {
+                        db.execSQL(multiLineQuery.toString());
+                        multiLineQuery = null;
+                    }
+                } else {
+                    if (count % 2 == 0) {
+                        db.execSQL(line);
+                    } else {
+                        multiLineQuery = new StringBuilder(line);
+                    }
+                }
+            }
+            Log.d(Config.LOGTAG, "done reading file");
+            stopBackgroundService();
+            synchronized (mOnBackupProcessedListeners) {
+                for (OnBackupProcessed l : mOnBackupProcessedListeners) {
+                    l.onBackupRestored();
+                }
+            }
+            return true;
+        } catch (Exception e) {
+            Throwable throwable = e.getCause();
+            final boolean reasonWasCrypto;
+            if (throwable instanceof BadPaddingException) {
+                reasonWasCrypto = true;
+            } else {
+                reasonWasCrypto = false;
+            }
+            synchronized (mOnBackupProcessedListeners) {
+                for (OnBackupProcessed l : mOnBackupProcessedListeners) {
+                    if (reasonWasCrypto) {
+                        l.onBackupDecryptionFailed();
+                    } else {
+                        l.onBackupRestoreFailed();
+                    }
+                }
+            }
+            Log.d(Config.LOGTAG, "error restoring backup " + file.getAbsolutePath(), e);
+            return false;
+        }
+    }
+
+    private void notifySuccess() {
+        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getBaseContext(), "backup");
+        mBuilder.setContentTitle(getString(R.string.notification_restored_backup_title))
+                .setContentText(getString(R.string.notification_restored_backup_subtitle))
+                .setAutoCancel(true)
+                .setContentIntent(PendingIntent.getActivity(this, 145, new Intent(this, ManageAccountActivity.class), PendingIntent.FLAG_UPDATE_CURRENT))
+                .setSmallIcon(R.drawable.ic_unarchive_white_24dp);
+        notificationManager.notify(NOTIFICATION_ID,mBuilder.build());
+    }
+
+    private void stopBackgroundService() {
+        Intent intent = new Intent(this, XmppConnectionService.class);
+        stopService(intent);
+    }
+
+    public void removeOnBackupProcessedListener(OnBackupProcessed listener) {
+        synchronized (mOnBackupProcessedListeners) {
+            mOnBackupProcessedListeners.remove(listener);
+        }
+    }
+
+    public void addOnBackupProcessedListener(OnBackupProcessed listener) {
+        synchronized (mOnBackupProcessedListeners) {
+            mOnBackupProcessedListeners.add(listener);
+        }
+    }
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        return this.binder;
+    }
+
+    public static class BackupFile {
+        private final File file;
+        private final BackupFileHeader header;
+
+        private BackupFile(File file, BackupFileHeader header) {
+            this.file = file;
+            this.header = header;
+        }
+
+        private static BackupFile read(File file) throws IOException {
+            final FileInputStream fileInputStream = new FileInputStream(file);
+            final DataInputStream dataInputStream = new DataInputStream(fileInputStream);
+            BackupFileHeader backupFileHeader = BackupFileHeader.read(dataInputStream);
+            fileInputStream.close();
+            return new BackupFile(file, backupFileHeader);
+        }
+
+        public BackupFileHeader getHeader() {
+            return header;
+        }
+
+        public File getFile() {
+            return file;
+        }
+    }
+
+    public class ImportBackupServiceBinder extends Binder {
+        public ImportBackupService getService() {
+            return ImportBackupService.this;
+        }
+    }
+
+    public interface OnBackupFilesLoaded {
+        void onBackupFilesLoaded(List<BackupFile> files);
+    }
+
+    public interface OnBackupProcessed {
+        void onBackupRestored();
+        void onBackupDecryptionFailed();
+        void onBackupRestoreFailed();
+    }
+}
--- a/src/conversations/java/eu/siacs/conversations/ui/ImportBackupActivity.java
+++ b/src/conversations/java/eu/siacs/conversations/ui/ImportBackupActivity.java
@ -0,0 +1,125 @@
+package eu.siacs.conversations.ui;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.databinding.DataBindingUtil;
+import android.databinding.ViewDataBinding;
+import android.os.Bundle;
+import android.os.IBinder;
+import android.support.design.widget.Snackbar;
+import android.support.v4.content.ContextCompat;
+import android.support.v7.app.AlertDialog;
+import android.support.v7.widget.Toolbar;
+import android.util.Log;
+import android.view.LayoutInflater;
+import android.widget.Toast;
+
+import java.util.List;
+
+import eu.siacs.conversations.Config;
+import eu.siacs.conversations.R;
+import eu.siacs.conversations.databinding.ActivityImportBackupBinding;
+import eu.siacs.conversations.databinding.DialogEnterPasswordBinding;
+import eu.siacs.conversations.services.ImportBackupService;
+import eu.siacs.conversations.ui.adapter.BackupFileAdapter;
+
+public class ImportBackupActivity extends ActionBarActivity implements ServiceConnection, ImportBackupService.OnBackupFilesLoaded, BackupFileAdapter.OnItemClickedListener, ImportBackupService.OnBackupProcessed {
+
+    private ActivityImportBackupBinding binding;
+
+    private BackupFileAdapter backupFileAdapter;
+    private ImportBackupService service;
+
+    @Override
+    protected void onCreate(final Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        binding = DataBindingUtil.setContentView(this, R.layout.activity_import_backup);
+        setSupportActionBar((Toolbar) binding.toolbar);
+        configureActionBar(getSupportActionBar());
+        this.backupFileAdapter = new BackupFileAdapter();
+        this.binding.list.setAdapter(this.backupFileAdapter);
+        this.backupFileAdapter.setOnItemClickedListener(this);
+    }
+
+    @Override
+    public void onStart() {
+        super.onStart();
+        bindService(new Intent(this, ImportBackupService.class), this, Context.BIND_AUTO_CREATE);
+    }
+
+    @Override
+    public void onStop() {
+        super.onStop();
+        if (this.service != null) {
+            this.service.removeOnBackupProcessedListener(this);
+        }
+        unbindService(this);
+    }
+
+    @Override
+    public void onServiceConnected(ComponentName name, IBinder service) {
+        ImportBackupService.ImportBackupServiceBinder binder = (ImportBackupService.ImportBackupServiceBinder) service;
+        this.service = binder.getService();
+        this.service.addOnBackupProcessedListener(this);
+        this.service.loadBackupFiles(this);
+    }
+
+    @Override
+    public void onServiceDisconnected(ComponentName name) {
+        this.service = null;
+    }
+
+    @Override
+    public void onBackupFilesLoaded(final List<ImportBackupService.BackupFile> files) {
+        runOnUiThread(() -> {
+            backupFileAdapter.setFiles(files);
+        });
+    }
+
+    @Override
+    public void onClick(ImportBackupService.BackupFile backupFile) {
+        final DialogEnterPasswordBinding enterPasswordBinding = DataBindingUtil.inflate(LayoutInflater.from(this), R.layout.dialog_enter_password, null, false);
+        Log.d(Config.LOGTAG, "attempting to import " + backupFile.getFile().getAbsolutePath());
+        enterPasswordBinding.explain.setText(getString(R.string.enter_password_to_restore, backupFile.getHeader().getJid().toString()));
+        AlertDialog.Builder builder = new AlertDialog.Builder(this);
+        builder.setView(enterPasswordBinding.getRoot());
+        builder.setTitle(R.string.enter_password);
+        builder.setNegativeButton(R.string.cancel, null);
+        builder.setPositiveButton(R.string.restore, (dialog, which) -> {
+            final String password = enterPasswordBinding.accountPassword.getEditableText().toString();
+            Intent intent = new Intent(this, ImportBackupService.class);
+            intent.putExtra("password", password);
+            intent.putExtra("file", backupFile.getFile().getAbsolutePath());
+            ContextCompat.startForegroundService(this, intent);
+        });
+        builder.setCancelable(false);
+        builder.create().show();
+    }
+
+    @Override
+    public void onBackupRestored() {
+        runOnUiThread(() -> {
+            Intent intent = new Intent(this, ConversationActivity.class);
+            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
+            startActivity(intent);
+            finish();
+        });
+    }
+
+    @Override
+    public void onBackupDecryptionFailed() {
+        runOnUiThread(()-> {
+            Snackbar.make(binding.coordinator,R.string.unable_to_decrypt_backup,Snackbar.LENGTH_LONG).show();
+        });
+    }
+
+    @Override
+    public void onBackupRestoreFailed() {
+        runOnUiThread(()-> {
+            Snackbar.make(binding.coordinator,R.string.unable_to_restore_backup,Snackbar.LENGTH_LONG).show();
+        });
+    }
+}
--- a/src/conversations/java/eu/siacs/conversations/ui/ManageAccountActivity.java
+++ b/src/conversations/java/eu/siacs/conversations/ui/ManageAccountActivity.java
@ -198,8 +198,10 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
        }
        switch (item.getItemId()) {
            case R.id.action_add_account:
-				startActivity(new Intent(getApplicationContext(),
-						EditAccountActivity.class));
+                startActivity(new Intent(this, EditAccountActivity.class));
+                break;
+            case R.id.action_import_backup:
+                startActivity(new Intent(this, ImportBackupActivity.class));
                break;
            case R.id.action_disable_all:
                disableAllAccounts();
@ -314,7 +316,7 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
    private void disableAccount(Account account) {
        account.setOption(Account.OPTION_DISABLED, true);
        if (!xmppConnectionService.updateAccount(account)) {
-			Toast.makeText(this,R.string.unable_to_update_account,Toast.LENGTH_SHORT).show();
+            Toast.makeText(this, R.string.unable_to_update_account, Toast.LENGTH_SHORT).show();
        }
    }

@ -325,13 +327,13 @@ public class ManageAccountActivity extends XmppActivity implements OnAccountUpda
            connection.resetEverything();
        }
        if (!xmppConnectionService.updateAccount(account)) {
-			Toast.makeText(this,R.string.unable_to_update_account,Toast.LENGTH_SHORT).show();
+            Toast.makeText(this, R.string.unable_to_update_account, Toast.LENGTH_SHORT).show();
        }
    }

    private void publishOpenPGPPublicKey(Account account) {
        if (ManageAccountActivity.this.hasPgp()) {
-			announcePgp(selectedAccount, null,null, onOpenPGPKeyPublished);
+            announcePgp(selectedAccount, null, null, onOpenPGPKeyPublished);
        } else {
            this.showInstallPgpDialog();
        }
--- a/src/conversations/java/eu/siacs/conversations/ui/WelcomeActivity.java
+++ b/src/conversations/java/eu/siacs/conversations/ui/WelcomeActivity.java
@ -3,14 +3,18 @@ package eu.siacs.conversations.ui;
 import android.content.Intent;
 import android.content.pm.ActivityInfo;
 import android.os.Bundle;
+import android.support.v4.content.ContextCompat;
 import android.support.v7.app.ActionBar;
 import android.support.v7.app.AppCompatActivity;
+import android.view.Menu;
+import android.view.MenuItem;
 import android.widget.Button;

 import java.util.List;

 import eu.siacs.conversations.R;
 import eu.siacs.conversations.entities.Account;
+import eu.siacs.conversations.services.ImportBackupService;
 import eu.siacs.conversations.utils.XmppUri;

 public class WelcomeActivity extends XmppActivity {
@ -77,6 +81,21 @@ public class WelcomeActivity extends XmppActivity {

    }

+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        getMenuInflater().inflate(R.menu.welcome_menu, menu);
+        return super.onCreateOptionsMenu(menu);
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        if (item.getItemId() == R.id.action_import_backup) {
+            startActivity(new Intent(this, ImportBackupActivity.class));
+            return true;
+        }
+        return super.onOptionsItemSelected(item);
+    }
+
    public void addInviteUri(Intent intent) {
        StartConversationActivity.addInviteUri(intent, getIntent());
    }
@ -85,7 +104,7 @@ public class WelcomeActivity extends XmppActivity {
        Intent intent = new Intent(activity, WelcomeActivity.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
        activity.startActivity(intent);
-		activity.overridePendingTransition(0,0);
+        activity.overridePendingTransition(0, 0);
    }

 }
--- a/src/conversations/java/eu/siacs/conversations/ui/adapter/BackupFileAdapter.java
+++ b/src/conversations/java/eu/siacs/conversations/ui/adapter/BackupFileAdapter.java
@ -0,0 +1,169 @@
+package eu.siacs.conversations.ui.adapter;
+
+import android.content.res.Resources;
+import android.databinding.DataBindingUtil;
+import android.graphics.Bitmap;
+import android.graphics.drawable.BitmapDrawable;
+import android.graphics.drawable.Drawable;
+import android.os.AsyncTask;
+import android.support.annotation.NonNull;
+import android.support.v7.widget.RecyclerView;
+import android.text.format.DateUtils;
+import android.util.DisplayMetrics;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ImageView;
+
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.RejectedExecutionException;
+
+import eu.siacs.conversations.R;
+import eu.siacs.conversations.databinding.AccountRowBinding;
+import eu.siacs.conversations.services.AvatarService;
+import eu.siacs.conversations.services.ImportBackupService;
+import eu.siacs.conversations.utils.BackupFileHeader;
+import eu.siacs.conversations.utils.UIHelper;
+import rocks.xmpp.addr.Jid;
+
+public class BackupFileAdapter extends RecyclerView.Adapter<BackupFileAdapter.BackupFileViewHolder> {
+
+    private OnItemClickedListener listener;
+
+    private final List<ImportBackupService.BackupFile> files = new ArrayList<>();
+
+
+    @NonNull
+    @Override
+    public BackupFileViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
+        return new BackupFileViewHolder(DataBindingUtil.inflate(LayoutInflater.from(viewGroup.getContext()), R.layout.account_row, viewGroup, false));
+    }
+
+    @Override
+    public void onBindViewHolder(@NonNull BackupFileViewHolder backupFileViewHolder, int position) {
+        final ImportBackupService.BackupFile backupFile = files.get(position);
+        final BackupFileHeader header = backupFile.getHeader();
+        backupFileViewHolder.binding.accountJid.setText(header.getJid().asBareJid().toString());
+        backupFileViewHolder.binding.accountStatus.setText(String.format("%s · %s",header.getApp(), DateUtils.formatDateTime(backupFileViewHolder.binding.getRoot().getContext(), header.getTimestamp(), DateUtils.FORMAT_SHOW_DATE | DateUtils.FORMAT_SHOW_YEAR)));
+        backupFileViewHolder.binding.tglAccountStatus.setVisibility(View.GONE);
+        backupFileViewHolder.binding.getRoot().setOnClickListener(v -> {
+            if (listener != null) {
+                listener.onClick(backupFile);
+            }
+        });
+        loadAvatar(header.getJid(), backupFileViewHolder.binding.accountImage);
+    }
+
+    @Override
+    public int getItemCount() {
+        return files.size();
+    }
+
+    public void setFiles(List<ImportBackupService.BackupFile> files) {
+        this.files.clear();
+        this.files.addAll(files);
+        notifyDataSetChanged();
+    }
+
+    public void setOnItemClickedListener(OnItemClickedListener listener) {
+        this.listener = listener;
+    }
+
+    static class BackupFileViewHolder extends RecyclerView.ViewHolder {
+        private final AccountRowBinding binding;
+
+        BackupFileViewHolder(AccountRowBinding binding) {
+            super(binding.getRoot());
+            this.binding = binding;
+        }
+
+    }
+
+    public interface OnItemClickedListener {
+        void onClick(ImportBackupService.BackupFile backupFile);
+    }
+
+    static class BitmapWorkerTask extends AsyncTask<Jid, Void, Bitmap> {
+        private final WeakReference<ImageView> imageViewReference;
+        private Jid jid  = null;
+        private final int size;
+
+        BitmapWorkerTask(ImageView imageView) {
+            imageViewReference = new WeakReference<>(imageView);
+            DisplayMetrics metrics = imageView.getContext().getResources().getDisplayMetrics();
+		this.size = ((int) (48 * metrics.density));
+        }
+
+        @Override
+        protected Bitmap doInBackground(Jid... params) {
+            this.jid = params[0];
+            return AvatarService.get(this.jid, size);
+        }
+
+        @Override
+        protected void onPostExecute(Bitmap bitmap) {
+            if (bitmap != null && !isCancelled()) {
+                final ImageView imageView = imageViewReference.get();
+                if (imageView != null) {
+                    imageView.setImageBitmap(bitmap);
+                    imageView.setBackgroundColor(0x00000000);
+                }
+            }
+        }
+    }
+
+    private void loadAvatar(Jid jid, ImageView imageView) {
+        if (cancelPotentialWork(jid, imageView)) {
+            imageView.setBackgroundColor(UIHelper.getColorForName(jid.asBareJid().toString()));
+            imageView.setImageDrawable(null);
+            final BitmapWorkerTask task = new BitmapWorkerTask(imageView);
+            final AsyncDrawable asyncDrawable = new AsyncDrawable(imageView.getContext().getResources(), null, task);
+            imageView.setImageDrawable(asyncDrawable);
+            try {
+                task.execute(jid);
+            } catch (final RejectedExecutionException ignored) {
+            }
+        }
+    }
+
+    private static boolean cancelPotentialWork(Jid jid, ImageView imageView) {
+        final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
+
+        if (bitmapWorkerTask != null) {
+            final Jid oldJid = bitmapWorkerTask.jid;
+            if (oldJid == null || jid != oldJid) {
+                bitmapWorkerTask.cancel(true);
+            } else {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    private static BitmapWorkerTask getBitmapWorkerTask(ImageView imageView) {
+        if (imageView != null) {
+            final Drawable drawable = imageView.getDrawable();
+            if (drawable instanceof AsyncDrawable) {
+                final AsyncDrawable asyncDrawable = (AsyncDrawable) drawable;
+                return asyncDrawable.getBitmapWorkerTask();
+            }
+        }
+        return null;
+    }
+
+    static class AsyncDrawable extends BitmapDrawable {
+        private final WeakReference<BitmapWorkerTask> bitmapWorkerTaskReference;
+
+        AsyncDrawable(Resources res, Bitmap bitmap, BitmapWorkerTask bitmapWorkerTask) {
+            super(res, bitmap);
+            bitmapWorkerTaskReference = new WeakReference<>(bitmapWorkerTask);
+        }
+
+        BitmapWorkerTask getBitmapWorkerTask() {
+            return bitmapWorkerTaskReference.get();
+        }
+    }
+
+}
--- a/src/conversations/res/drawable-hdpi/ic_unarchive_white_24dp.png
+++ b/src/conversations/res/drawable-hdpi/ic_unarchive_white_24dp.png
--- a/src/conversations/res/drawable-mdpi/ic_unarchive_white_24dp.png
+++ b/src/conversations/res/drawable-mdpi/ic_unarchive_white_24dp.png
--- a/src/conversations/res/drawable-xhdpi/ic_unarchive_white_24dp.png
+++ b/src/conversations/res/drawable-xhdpi/ic_unarchive_white_24dp.png
--- a/src/conversations/res/drawable-xxhdpi/ic_unarchive_white_24dp.png
+++ b/src/conversations/res/drawable-xxhdpi/ic_unarchive_white_24dp.png
--- a/src/conversations/res/drawable-xxxhdpi/ic_unarchive_white_24dp.png
+++ b/src/conversations/res/drawable-xxxhdpi/ic_unarchive_white_24dp.png
--- a/src/conversations/res/layout/activity_import_backup.xml
+++ b/src/conversations/res/layout/activity_import_backup.xml
@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+
+    <LinearLayout
+        android:layout_width="fill_parent"
+        android:layout_height="fill_parent"
+        android:background="?attr/color_background_primary"
+        android:orientation="vertical">
+
+        <include
+            android:id="@+id/toolbar"
+            layout="@layout/toolbar" />
+
+        <android.support.design.widget.CoordinatorLayout
+            android:id="@+id/coordinator"
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:background="?attr/color_background_primary">
+
+            <android.support.v7.widget.RecyclerView
+                android:id="@+id/list"
+                android:layout_width="match_parent"
+                android:layout_height="match_parent"
+                android:background="?attr/color_background_primary"
+                android:orientation="vertical"
+                app:layoutManager="android.support.v7.widget.LinearLayoutManager" />
+        </android.support.design.widget.CoordinatorLayout>
+
+    </LinearLayout>
+</layout>
--- a/src/conversations/res/layout/dialog_enter_password.xml
+++ b/src/conversations/res/layout/dialog_enter_password.xml
@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:android="http://schemas.android.com/apk/res/android"
+        xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <LinearLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:orientation="vertical"
+        android:padding="?dialogPreferredPadding">
+
+        <TextView
+            android:id="@+id/explain"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/enter_password_to_restore"
+            android:textAppearance="@style/TextAppearance.Conversations.Body2"/>
+
+        <TextView
+            android:layout_marginTop="?TextSizeBody1"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:text="@string/restore_warning"
+            android:textAppearance="@style/TextAppearance.Conversations.Body1"/>
+
+        <android.support.design.widget.TextInputLayout
+            android:id="@+id/account_password_layout"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:layout_marginTop="8dp"
+            app:passwordToggleDrawable="@drawable/visibility_toggle_drawable"
+            app:passwordToggleEnabled="true"
+            app:passwordToggleTint="?android:textColorSecondary"
+            app:hintTextAppearance="@style/TextAppearance.Conversations.Design.Hint"
+            app:errorTextAppearance="@style/TextAppearance.Conversations.Design.Error">
+
+        <eu.siacs.conversations.ui.widget.TextInputEditText
+            android:id="@+id/account_password"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:hint="@string/password"
+            android:inputType="textPassword"
+            android:textColor="?attr/edit_text_color"
+            style="@style/Widget.Conversations.EditText"/>
+
+        </android.support.design.widget.TextInputLayout>
+    </LinearLayout>
+</layout>
--- a/src/conversations/res/menu/manageaccounts.xml
+++ b/src/conversations/res/menu/manageaccounts.xml
@ -7,6 +7,10 @@
 		android:icon="?attr/icon_add_person"
 		app:showAsAction="always"
 		android:title="@string/action_add_account"/>
+	<item
+		android:id="@+id/action_import_backup"
+		app:showAsAction="never"
+		android:title="@string/restore_backup"/>
 	<item
 		android:id="@+id/action_add_account_with_cert"
 		app:showAsAction="never"
--- a/src/conversations/res/menu/welcome_menu.xml
+++ b/src/conversations/res/menu/welcome_menu.xml
@ -0,0 +1,8 @@
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+      xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <item
+        android:id="@+id/action_import_backup"
+        app:showAsAction="never"
+        android:title="@string/restore_backup"/>
+</menu>
--- a/src/main/AndroidManifest.xml
+++ b/src/main/AndroidManifest.xml
@ -245,7 +245,8 @@
        <activity android:name=".ui.MediaBrowserActivity"
            android:label="@string/media_browser"/>

-        <service android:name=".services.ExportLogsService"/>
+        <service android:name=".services.ExportBackupService"/>
+        <service android:name=".services.ImportBackupService"/>
        <service
            android:name=".services.ContactChooserTargetService"
            android:permission="android.permission.BIND_CHOOSER_TARGET_SERVICE">
--- a/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
+++ b/src/main/java/eu/siacs/conversations/persistance/FileBackend.java
@ -150,8 +150,12 @@ public class FileBackend {
        return Environment.getExternalStorageDirectory().getAbsolutePath() + "/" + context.getString(R.string.app_name) + "/Media/";
    }

-    public static String getConversationsLogsDirectory() {
-        return Environment.getExternalStorageDirectory().getAbsolutePath() + "/Conversations/";
+    public static String getBackupDirectory(Context context) {
+        return getBackupDirectory(context.getString(R.string.app_name));
+    }
+
+    public static String getBackupDirectory(String app) {
+        return Environment.getExternalStorageDirectory().getAbsolutePath() + "/"+app+"/Backup/";
    }

    private static Bitmap rotate(Bitmap bitmap, int degree) {
--- a/src/main/java/eu/siacs/conversations/services/AvatarService.java
+++ b/src/main/java/eu/siacs/conversations/services/AvatarService.java
@ -511,7 +511,11 @@ public class AvatarService implements OnAdvancedStreamFeaturesLoaded {
 		return bitmap;
 	}

-	private Bitmap getImpl(final String name, final String seed, final int size) {
+	public static Bitmap get(final Jid jid, final int size) {
+		return getImpl(jid.asBareJid().toEscapedString(), null, size);
+	}
+
+	private static Bitmap getImpl(final String name, final String seed, final int size) {
 		Bitmap bitmap = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
 		Canvas canvas = new Canvas(bitmap);
 		final String trimmedName = name == null ? "" : name.trim();
@ -528,7 +532,7 @@ public class AvatarService implements OnAdvancedStreamFeaturesLoaded {
 		return PREFIX_GENERIC + "_" + name + "_" + String.valueOf(size);
 	}

-	private boolean drawTile(Canvas canvas, String letter, int tileColor, int left, int top, int right, int bottom) {
+	private static boolean drawTile(Canvas canvas, String letter, int tileColor, int left, int top, int right, int bottom) {
 		letter = letter.toUpperCase(Locale.getDefault());
 		Paint tilePaint = new Paint(), textPaint = new Paint();
 		tilePaint.setColor(tileColor);
@ -591,7 +595,7 @@ public class AvatarService implements OnAdvancedStreamFeaturesLoaded {
 		return drawTile(canvas, name, name, left, top, right, bottom);
 	}

-	private boolean drawTile(Canvas canvas, String name, String seed, int left, int top, int right, int bottom) {
+	private static boolean drawTile(Canvas canvas, String name, String seed, int left, int top, int right, int bottom) {
 		if (name != null) {
 			final String letter = getFirstLetter(name);
 			final int color = UIHelper.getColorForName(seed == null ? name : seed);
--- a/src/main/java/eu/siacs/conversations/services/ExportBackupService.java
+++ b/src/main/java/eu/siacs/conversations/services/ExportBackupService.java
@ -0,0 +1,281 @@
+package eu.siacs.conversations.services;
+
+import android.app.Notification;
+import android.app.NotificationManager;
+import android.app.Service;
+import android.content.Context;
+import android.content.Intent;
+import android.database.Cursor;
+import android.database.DatabaseUtils;
+import android.database.sqlite.SQLiteDatabase;
+import android.os.IBinder;
+import android.support.v4.app.NotificationCompat;
+import android.util.Log;
+
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.PrintWriter;
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+import java.security.spec.InvalidKeySpecException;
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.zip.GZIPOutputStream;
+
+import javax.crypto.Cipher;
+import javax.crypto.CipherOutputStream;
+import javax.crypto.SecretKeyFactory;
+import javax.crypto.spec.IvParameterSpec;
+import javax.crypto.spec.PBEKeySpec;
+import javax.crypto.spec.SecretKeySpec;
+
+import eu.siacs.conversations.Config;
+import eu.siacs.conversations.R;
+import eu.siacs.conversations.crypto.axolotl.SQLiteAxolotlStore;
+import eu.siacs.conversations.entities.Account;
+import eu.siacs.conversations.entities.Conversation;
+import eu.siacs.conversations.entities.Message;
+import eu.siacs.conversations.persistance.DatabaseBackend;
+import eu.siacs.conversations.persistance.FileBackend;
+import eu.siacs.conversations.utils.BackupFileHeader;
+import eu.siacs.conversations.utils.Compatibility;
+
+public class ExportBackupService extends Service {
+
+    public static final String KEYTYPE = "AES";
+    public static final String CIPHERMODE = "AES/GCM/NoPadding";
+    public static final String PROVIDER = "BC";
+
+    private static final int NOTIFICATION_ID = 19;
+    private static AtomicBoolean running = new AtomicBoolean(false);
+    private DatabaseBackend mDatabaseBackend;
+    private List<Account> mAccounts;
+    private NotificationManager notificationManager;
+
+    @Override
+    public void onCreate() {
+        mDatabaseBackend = DatabaseBackend.getInstance(getBaseContext());
+        mAccounts = mDatabaseBackend.getAccounts();
+        notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
+    }
+
+    @Override
+    public int onStartCommand(Intent intent, int flags, int startId) {
+        if (running.compareAndSet(false, true)) {
+            new Thread(() -> {
+                export();
+                stopForeground(true);
+                running.set(false);
+                stopSelf();
+            }).start();
+        }
+        return START_NOT_STICKY;
+    }
+
+    private static void accountExport(SQLiteDatabase db, String uuid, PrintWriter writer) {
+        StringBuilder builder = new StringBuilder();
+        final Cursor accountCursor = db.query(Account.TABLENAME, null, Account.UUID + "=?", new String[]{uuid}, null, null, null);
+        while (accountCursor != null && accountCursor.moveToNext()) {
+            builder.append("INSERT INTO ").append(Account.TABLENAME).append("(");
+            for (int i = 0; i < accountCursor.getColumnCount(); ++i) {
+                if (i != 0) {
+                    builder.append(',');
+                }
+                builder.append(accountCursor.getColumnName(i));
+            }
+            builder.append(") VALUES(");
+            for (int i = 0; i < accountCursor.getColumnCount(); ++i) {
+                if (i != 0) {
+                    builder.append(',');
+                }
+                final String value = accountCursor.getString(i);
+                if (value == null || Account.ROSTERVERSION.equals(accountCursor.getColumnName(i))) {
+                    builder.append("NULL");
+                } else if (value.matches("\\d+")) {
+                    int intValue = Integer.parseInt(value);
+                    Log.d(Config.LOGTAG,"reading int value. "+intValue);
+                    if (Account.OPTIONS.equals(accountCursor.getColumnName(i))) {
+                        intValue |= 1 << Account.OPTION_DISABLED;
+                        Log.d(Config.LOGTAG,"modified int value "+intValue);
+                    }
+                    builder.append(intValue);
+                } else {
+                    DatabaseUtils.appendEscapedSQLString(builder, value);
+                }
+            }
+            builder.append(")");
+            builder.append(';');
+            builder.append('\n');
+        }
+        Log.d(Config.LOGTAG,builder.toString());
+        if (accountCursor != null) {
+            accountCursor.close();
+        }
+        writer.append(builder.toString());
+    }
+
+    private void messageExport(SQLiteDatabase db, String uuid, PrintWriter writer, Progress progress) {
+        Cursor cursor = db.rawQuery("select messages.* from messages join conversations on conversations.uuid=messages.conversationUuid where conversations.accountUuid=?", new String[]{uuid});
+        int size = cursor != null ? cursor.getCount() : 0;
+        Log.d(Config.LOGTAG, "exporting " + size + " messages");
+        int i = 0;
+        int p = 0;
+        while (cursor != null && cursor.moveToNext()) {
+            writer.write(cursorToString(Message.TABLENAME, cursor, 20));
+            if (i + 20 > size) {
+                i = size;
+            } else {
+                i += 20;
+            }
+            final int percentage = i * 100 / size;
+            if (p < percentage) {
+                p = percentage;
+                notificationManager.notify(NOTIFICATION_ID,progress.build(p));
+                Log.d(Config.LOGTAG, "percentage=" + p);
+            }
+        }
+        if (cursor != null) {
+            cursor.close();
+        }
+    }
+
+    private static void simpleExport(SQLiteDatabase db, String table, String column, String uuid, PrintWriter writer) {
+        final Cursor cursor = db.query(table, null, column + "=?", new String[]{uuid}, null, null, null);
+        while (cursor != null && cursor.moveToNext()) {
+            writer.write(cursorToString(table, cursor, 20));
+        }
+        if (cursor != null) {
+            cursor.close();
+        }
+    }
+
+    private void export() {
+        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getBaseContext(), "backup");
+        mBuilder.setContentTitle(getString(R.string.notification_create_backup_title))
+                .setSmallIcon(R.drawable.ic_archive_white_24dp)
+                .setProgress(1, 0, false);
+        startForeground(NOTIFICATION_ID, mBuilder.build());
+        try {
+            int count = 0;
+            final int max = this.mAccounts.size();
+            final SecureRandom secureRandom = new SecureRandom();
+            for (Account account : this.mAccounts) {
+                final byte[] IV = new byte[12];
+                final byte[] salt = new byte[16];
+                secureRandom.nextBytes(IV);
+                secureRandom.nextBytes(salt);
+                final BackupFileHeader backupFileHeader = new BackupFileHeader(getString(R.string.app_name),account.getJid(),System.currentTimeMillis(),IV,salt);
+                final Progress progress = new Progress(mBuilder, max, count);
+                final File file = new File(FileBackend.getBackupDirectory(this)+account.getJid().asBareJid().toEscapedString()+".ceb");
+                if (file.getParentFile().mkdirs()) {
+                    Log.d(Config.LOGTAG,"created backup directory "+file.getParentFile().getAbsolutePath());
+                }
+                final FileOutputStream fileOutputStream = new FileOutputStream(file);
+                final DataOutputStream dataOutputStream = new DataOutputStream(fileOutputStream);
+                backupFileHeader.write(dataOutputStream);
+                dataOutputStream.flush();
+
+                final Cipher cipher = Compatibility.twentyEight() ? Cipher.getInstance(CIPHERMODE) : Cipher.getInstance(CIPHERMODE, PROVIDER);
+                byte[] key = getKey(account.getPassword(), salt);
+                Log.d(Config.LOGTAG,backupFileHeader.toString());
+                SecretKeySpec keySpec = new SecretKeySpec(key, KEYTYPE);
+                IvParameterSpec ivSpec = new IvParameterSpec(IV);
+                cipher.init(Cipher.ENCRYPT_MODE, keySpec, ivSpec);
+                CipherOutputStream cipherOutputStream = new CipherOutputStream(fileOutputStream, cipher);
+
+                GZIPOutputStream gzipOutputStream = new GZIPOutputStream(cipherOutputStream);
+                PrintWriter writer = new PrintWriter(gzipOutputStream);
+                SQLiteDatabase db = this.mDatabaseBackend.getReadableDatabase();
+                final String uuid = account.getUuid();
+                accountExport(db, uuid, writer);
+                simpleExport(db, Conversation.TABLENAME, Conversation.ACCOUNT, uuid, writer);
+                messageExport(db, uuid, writer, progress);
+                for(String table : Arrays.asList(SQLiteAxolotlStore.PREKEY_TABLENAME, SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME, SQLiteAxolotlStore.SESSION_TABLENAME, SQLiteAxolotlStore.IDENTITIES_TABLENAME)) {
+                    simpleExport(db, table, SQLiteAxolotlStore.ACCOUNT,uuid,writer);
+                }
+                writer.flush();
+                writer.close();
+                Log.d(Config.LOGTAG, "written backup to " + file.getAbsoluteFile());
+                count++;
+            }
+        } catch (Exception e) {
+            Log.d(Config.LOGTAG, "unable to create backup ", e);
+        }
+    }
+
+    public static byte[] getKey(String password, byte[] salt) {
+        try {
+            SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
+            return factory.generateSecret(new PBEKeySpec(password.toCharArray(), salt, 1024, 128)).getEncoded();
+        } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
+            throw new AssertionError(e);
+        }
+    }
+
+    private static String cursorToString(String tablename, Cursor cursor, int max) {
+        StringBuilder builder = new StringBuilder();
+        builder.append("INSERT INTO ").append(tablename).append("(");
+        for (int i = 0; i < cursor.getColumnCount(); ++i) {
+            if (i != 0) {
+                builder.append(',');
+            }
+            builder.append(cursor.getColumnName(i));
+        }
+        builder.append(") VALUES");
+        for (int i = 0; i < max; ++i) {
+            if (i != 0) {
+                builder.append(',');
+            }
+            appendValues(cursor, builder);
+            if (!cursor.moveToNext()) {
+                break;
+            }
+        }
+        builder.append(';');
+        builder.append('\n');
+        return builder.toString();
+    }
+
+    private static void appendValues(Cursor cursor, StringBuilder builder) {
+        builder.append("(");
+        for (int i = 0; i < cursor.getColumnCount(); ++i) {
+            if (i != 0) {
+                builder.append(',');
+            }
+            final String value = cursor.getString(i);
+            if (value == null) {
+                builder.append("NULL");
+            } else if (value.matches("\\d+")) {
+                builder.append(value);
+            } else {
+                DatabaseUtils.appendEscapedSQLString(builder, value);
+            }
+        }
+        builder.append(")");
+
+    }
+
+    @Override
+    public IBinder onBind(Intent intent) {
+        return null;
+    }
+
+    private class Progress {
+        private final NotificationCompat.Builder builder;
+        private final int max;
+        private final int count;
+
+        private Progress(NotificationCompat.Builder builder, int max, int count) {
+            this.builder = builder;
+            this.max = max;
+            this.count = count;
+        }
+
+        private Notification build(int percentage) {
+            builder.setProgress(max * 100,count * 100 + percentage,false);
+            return builder.build();
+        }
+    }
+}
--- a/src/main/java/eu/siacs/conversations/services/ExportLogsService.java
+++ b/src/main/java/eu/siacs/conversations/services/ExportLogsService.java
@ -1,148 +0,0 @@
-package eu.siacs.conversations.services;
-
-import android.app.NotificationManager;
-import android.app.Service;
-import android.content.Context;
-import android.content.Intent;
-import android.os.IBinder;
-import android.support.v4.app.NotificationCompat;
-
-import java.io.BufferedWriter;
-import java.io.File;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.text.SimpleDateFormat;
-import java.util.Date;
-import java.util.List;
-import java.util.concurrent.atomic.AtomicBoolean;
-
-import eu.siacs.conversations.R;
-import eu.siacs.conversations.entities.Account;
-import eu.siacs.conversations.entities.Conversation;
-import eu.siacs.conversations.entities.Message;
-import eu.siacs.conversations.persistance.DatabaseBackend;
-import eu.siacs.conversations.persistance.FileBackend;
-import rocks.xmpp.addr.Jid;
-
-public class ExportLogsService extends Service {
-
-    private static final SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
-    private static final String DIRECTORY_STRING_FORMAT = FileBackend.getConversationsLogsDirectory() + "/logs/%s";
-    private static final String MESSAGE_STRING_FORMAT = "(%s) %s: %s\n";
-    private static final int NOTIFICATION_ID = 1;
-    private static AtomicBoolean running = new AtomicBoolean(false);
-    private DatabaseBackend mDatabaseBackend;
-    private List<Account> mAccounts;
-
-    @Override
-    public void onCreate() {
-        mDatabaseBackend = DatabaseBackend.getInstance(getBaseContext());
-        mAccounts = mDatabaseBackend.getAccounts();
-    }
-
-    @Override
-    public int onStartCommand(Intent intent, int flags, int startId) {
-        if (running.compareAndSet(false, true)) {
-            new Thread(() -> {
-                export();
-                stopForeground(true);
-                running.set(false);
-                stopSelf();
-            }).start();
-        }
-        return START_NOT_STICKY;
-    }
-
-    private void export() {
-        List<Conversation> conversations = mDatabaseBackend.getConversations(Conversation.STATUS_AVAILABLE);
-        conversations.addAll(mDatabaseBackend.getConversations(Conversation.STATUS_ARCHIVED));
-        NotificationManager mNotifyManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
-        NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getBaseContext(), "export");
-        mBuilder.setContentTitle(getString(R.string.notification_export_logs_title))
-                .setSmallIcon(R.drawable.ic_import_export_white_24dp)
-                .setProgress(conversations.size(), 0, false);
-        startForeground(NOTIFICATION_ID, mBuilder.build());
-
-        int progress = 0;
-        for (Conversation conversation : conversations) {
-            writeToFile(conversation);
-            progress++;
-            mBuilder.setProgress(conversations.size(), progress, false);
-            if (mNotifyManager != null) {
-                mNotifyManager.notify(NOTIFICATION_ID, mBuilder.build());
-            }
-        }
-    }
-
-    private void writeToFile(Conversation conversation) {
-        Jid accountJid = resolveAccountUuid(conversation.getAccountUuid());
-        Jid contactJid = conversation.getJid();
-
-        File dir = new File(String.format(DIRECTORY_STRING_FORMAT, accountJid.asBareJid().toString()));
-        dir.mkdirs();
-
-        BufferedWriter bw = null;
-        try {
-            for (Message message : mDatabaseBackend.getMessagesIterable(conversation)) {
-                if (message == null)
-                    continue;
-                if (message.getType() == Message.TYPE_TEXT || message.hasFileOnRemoteHost()) {
-                    String date = simpleDateFormat.format(new Date(message.getTimeSent()));
-                    if (bw == null) {
-                        bw = new BufferedWriter(new FileWriter(
-                                new File(dir, contactJid.asBareJid().toString() + ".txt")));
-                    }
-                    String jid = null;
-                    switch (message.getStatus()) {
-                        case Message.STATUS_RECEIVED:
-                            jid = getMessageCounterpart(message);
-                            break;
-                        case Message.STATUS_SEND:
-                        case Message.STATUS_SEND_RECEIVED:
-                        case Message.STATUS_SEND_DISPLAYED:
-                            jid = accountJid.asBareJid().toString();
-                            break;
-                    }
-                    if (jid != null) {
-                        String body = message.hasFileOnRemoteHost() ? message.getFileParams().url.toString() : message.getBody();
-                        bw.write(String.format(MESSAGE_STRING_FORMAT, date, jid,
-                                body.replace("\\\n", "\\ \n").replace("\n", "\\ \n")));
-                    }
-                }
-            }
-        } catch (IOException e) {
-            e.printStackTrace();
-        } finally {
-            try {
-                if (bw != null) {
-                    bw.close();
-                }
-            } catch (IOException e1) {
-                e1.printStackTrace();
-            }
-        }
-    }
-
-    private Jid resolveAccountUuid(String accountUuid) {
-        for (Account account : mAccounts) {
-            if (account.getUuid().equals(accountUuid)) {
-                return account.getJid();
-            }
-        }
-        return null;
-    }
-
-    private String getMessageCounterpart(Message message) {
-        String trueCounterpart = (String) message.getContentValues().get(Message.TRUE_COUNTERPART);
-        if (trueCounterpart != null) {
-            return trueCounterpart;
-        } else {
-            return message.getCounterpart().toString();
-        }
-    }
-
-    @Override
-    public IBinder onBind(Intent intent) {
-        return null;
-    }
-}
--- a/src/main/java/eu/siacs/conversations/services/NotificationService.java
+++ b/src/main/java/eu/siacs/conversations/services/NotificationService.java
@ -112,6 +112,8 @@ public class NotificationService {
            return;
        }

+        notificationManager.deleteNotificationChannel("export");
+
        notificationManager.createNotificationChannelGroup(new NotificationChannelGroup("status", c.getString(R.string.notification_group_status_information)));
        notificationManager.createNotificationChannelGroup(new NotificationChannelGroup("chats", c.getString(R.string.notification_group_messages)));
        final NotificationChannel foregroundServiceChannel = new NotificationChannel("foreground",
@ -136,8 +138,8 @@ public class NotificationService {
        videoCompressionChannel.setGroup("status");
        notificationManager.createNotificationChannel(videoCompressionChannel);

-        final NotificationChannel exportChannel = new NotificationChannel("export",
-                c.getString(R.string.export_channel_name),
+        final NotificationChannel exportChannel = new NotificationChannel("backup",
+                c.getString(R.string.backup_channel_name),
                NotificationManager.IMPORTANCE_LOW);
        exportChannel.setShowBadge(false);
        exportChannel.setGroup("status");
--- a/src/main/java/eu/siacs/conversations/ui/SettingsActivity.java
+++ b/src/main/java/eu/siacs/conversations/ui/SettingsActivity.java
@ -21,8 +21,6 @@ import android.preference.PreferenceManager;
 import android.preference.PreferenceScreen;
 import android.provider.MediaStore;
 import android.util.Log;
-import android.view.View;
-import android.view.ViewGroup;
 import android.widget.Toast;

 import java.io.File;
@ -36,7 +34,8 @@ import eu.siacs.conversations.Config;
 import eu.siacs.conversations.R;
 import eu.siacs.conversations.crypto.OmemoSetting;
 import eu.siacs.conversations.entities.Account;
-import eu.siacs.conversations.services.ExportLogsService;
+import eu.siacs.conversations.persistance.FileBackend;
+import eu.siacs.conversations.services.ExportBackupService;
 import eu.siacs.conversations.services.MemorizingTrustManager;
 import eu.siacs.conversations.services.QuickConversationsService;
 import eu.siacs.conversations.ui.util.StyledAttributes;
@ -59,7 +58,7 @@ public class SettingsActivity extends XmppActivity implements
 	public static final String SHOW_DYNAMIC_TAGS = "show_dynamic_tags";
 	public static final String OMEMO_SETTING = "omemo";

-	public static final int REQUEST_WRITE_LOGS = 0xbf8701;
+	public static final int REQUEST_CREATE_BACKUP = 0xbf8701;
 	private SettingsFragment mSettingsFragment;

 	@Override
@ -219,11 +218,12 @@ public class SettingsActivity extends XmppActivity implements
 			});
 		}

-		final Preference exportLogsPreference = mSettingsFragment.findPreference("export_logs");
-		if (exportLogsPreference != null) {
-			exportLogsPreference.setOnPreferenceClickListener(preference -> {
-				if (hasStoragePermission(REQUEST_WRITE_LOGS)) {
-					startExport();
+		final Preference createBackupPreference = mSettingsFragment.findPreference("create_backup");
+		if (createBackupPreference != null) {
+			createBackupPreference.setSummary(getString(R.string.pref_create_backup_summary, FileBackend.getBackupDirectory(this)));
+			createBackupPreference.setOnPreferenceClickListener(preference -> {
+				if (hasStoragePermission(REQUEST_CREATE_BACKUP)) {
+					createBackup();
 				}
 				return true;
 			});
@ -399,16 +399,16 @@ public class SettingsActivity extends XmppActivity implements
 	public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
 		if (grantResults.length > 0)
 			if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
-				if (requestCode == REQUEST_WRITE_LOGS) {
-					startExport();
+				if (requestCode == REQUEST_CREATE_BACKUP) {
+					createBackup();
 				}
 			} else {
 				Toast.makeText(this, R.string.no_storage_permission, Toast.LENGTH_SHORT).show();
 			}
 	}

-	private void startExport() {
-		ContextCompat.startForegroundService(this, new Intent(this, ExportLogsService.class));
+	private void createBackup() {
+		ContextCompat.startForegroundService(this, new Intent(this, ExportBackupService.class));
 	}

 	private void displayToast(final String msg) {
--- a/src/main/java/eu/siacs/conversations/ui/adapter/AccountAdapter.java
+++ b/src/main/java/eu/siacs/conversations/ui/adapter/AccountAdapter.java
@ -1,18 +1,17 @@
 package eu.siacs.conversations.ui.adapter;

-import android.content.Context;
 import android.content.res.Resources;
+import android.databinding.DataBindingUtil;
 import android.graphics.Bitmap;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.os.AsyncTask;
-import android.support.v7.widget.SwitchCompat;
+import android.support.annotation.NonNull;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.ArrayAdapter;
 import android.widget.ImageView;
-import android.widget.TextView;

 import java.lang.ref.WeakReference;
 import java.util.List;
@ -20,6 +19,7 @@ import java.util.concurrent.RejectedExecutionException;

 import eu.siacs.conversations.Config;
 import eu.siacs.conversations.R;
+import eu.siacs.conversations.databinding.AccountRowBinding;
 import eu.siacs.conversations.entities.Account;
 import eu.siacs.conversations.ui.XmppActivity;
 import eu.siacs.conversations.ui.util.StyledAttributes;
@ -43,45 +43,45 @@ public class AccountAdapter extends ArrayAdapter<Account> {
    }

    @Override
-	public View getView(int position, View view, ViewGroup parent) {
+    public View getView(int position, View view, @NonNull ViewGroup parent) {
        final Account account = getItem(position);
+        final ViewHolder viewHolder;
        if (view == null) {
-			LayoutInflater inflater = (LayoutInflater) getContext()
-					.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
-			view = inflater.inflate(R.layout.account_row, parent, false);
-		}
-		TextView jid = view.findViewById(R.id.account_jid);
-		if (Config.DOMAIN_LOCK != null) {
-			jid.setText(account.getJid().getLocal());
+            AccountRowBinding binding = DataBindingUtil.inflate(LayoutInflater.from(parent.getContext()), R.layout.account_row, parent, false);
+            view = binding.getRoot();
+            viewHolder = new ViewHolder(binding);
+            view.setTag(viewHolder);
        } else {
-			jid.setText(account.getJid().asBareJid().toString());
+            viewHolder = (ViewHolder) view.getTag();
        }
-		TextView statusView = view.findViewById(R.id.account_status);
-		ImageView imageView = view.findViewById(R.id.account_image);
-		loadAvatar(account, imageView);
-		statusView.setText(getContext().getString(account.getStatus().getReadableId()));
+        if (Config.DOMAIN_LOCK != null) {
+            viewHolder.binding.accountJid.setText(account.getJid().getLocal());
+        } else {
+            viewHolder.binding.accountJid.setText(account.getJid().asBareJid().toString());
+        }
+        loadAvatar(account, viewHolder.binding.accountImage);
+        viewHolder.binding.accountStatus.setText(getContext().getString(account.getStatus().getReadableId()));
        switch (account.getStatus()) {
            case ONLINE:
-				statusView.setTextColor(StyledAttributes.getColor(activity, R.attr.TextColorOnline));
+                viewHolder.binding.accountStatus.setTextColor(StyledAttributes.getColor(activity, R.attr.TextColorOnline));
                break;
            case DISABLED:
            case CONNECTING:
-				statusView.setTextColor(StyledAttributes.getColor(activity, android.R.attr.textColorSecondary));
+                viewHolder.binding.accountStatus.setTextColor(StyledAttributes.getColor(activity, android.R.attr.textColorSecondary));
                break;
            default:
-				statusView.setTextColor(StyledAttributes.getColor(activity, R.attr.TextColorError));
+                viewHolder.binding.accountStatus.setTextColor(StyledAttributes.getColor(activity, R.attr.TextColorError));
                break;
        }
-		final SwitchCompat tglAccountState = view.findViewById(R.id.tgl_account_status);
        final boolean isDisabled = (account.getStatus() == Account.State.DISABLED);
-		tglAccountState.setOnCheckedChangeListener(null);
-		tglAccountState.setChecked(!isDisabled);
+        viewHolder.binding.tglAccountStatus.setOnCheckedChangeListener(null);
+        viewHolder.binding.tglAccountStatus.setChecked(!isDisabled);
        if (this.showStateButton) {
-			tglAccountState.setVisibility(View.VISIBLE);
+            viewHolder.binding.tglAccountStatus.setVisibility(View.VISIBLE);
        } else {
-			tglAccountState.setVisibility(View.GONE);
+            viewHolder.binding.tglAccountStatus.setVisibility(View.GONE);
        }
-		tglAccountState.setOnCheckedChangeListener((compoundButton, b) -> {
+        viewHolder.binding.tglAccountStatus.setOnCheckedChangeListener((compoundButton, b) -> {
            if (b == isDisabled && activity instanceof OnTglAccountState) {
                ((OnTglAccountState) activity).onClickTglAccountState(account, b);
            }
@ -89,6 +89,14 @@ public class AccountAdapter extends ArrayAdapter<Account> {
        return view;
    }

+    private static class ViewHolder {
+        private final AccountRowBinding binding;
+
+        private ViewHolder(AccountRowBinding binding) {
+            this.binding = binding;
+        }
+    }
+
    class BitmapWorkerTask extends AsyncTask<Account, Void, Bitmap> {
        private final WeakReference<ImageView> imageViewReference;
        private Account account = null;
--- a/src/main/java/eu/siacs/conversations/utils/BackupFileHeader.java
+++ b/src/main/java/eu/siacs/conversations/utils/BackupFileHeader.java
@ -0,0 +1,85 @@
+package eu.siacs.conversations.utils;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.Arrays;
+
+import rocks.xmpp.addr.Jid;
+
+public class BackupFileHeader {
+
+    private static final int VERSION = 1;
+
+    private String app;
+    private Jid jid;
+    private long timestamp;
+    private byte[] iv;
+    private byte[] salt;
+
+
+    @Override
+    public String toString() {
+        return "BackupFileHeader{" +
+                "app='" + app + '\'' +
+                ", jid=" + jid +
+                ", timestamp=" + timestamp +
+                ", iv=" + CryptoHelper.bytesToHex(iv) +
+                ", salt=" + CryptoHelper.bytesToHex(salt) +
+                '}';
+    }
+
+    public BackupFileHeader(String app, Jid jid, long timestamp, byte[] iv, byte[] salt) {
+        this.app = app;
+        this.jid = jid;
+        this.timestamp = timestamp;
+        this.iv = iv;
+        this.salt = salt;
+    }
+
+    public void write(DataOutputStream dataOutputStream) throws IOException {
+        dataOutputStream.writeInt(VERSION);
+        dataOutputStream.writeUTF(app);
+        dataOutputStream.writeUTF(jid.asBareJid().toEscapedString());
+        dataOutputStream.writeLong(timestamp);
+        dataOutputStream.write(iv);
+        dataOutputStream.write(salt);
+    }
+
+    public static BackupFileHeader read(DataInputStream inputStream) throws IOException {
+        final int version = inputStream.readInt();
+        if (version > VERSION) {
+            throw new IllegalArgumentException("Backup File version was "+version+" but app only supports up to version "+VERSION);
+        }
+        String app = inputStream.readUTF();
+        String jid = inputStream.readUTF();
+        long timestamp = inputStream.readLong();
+        byte[] iv = new byte[12];
+        inputStream.readFully(iv);
+        byte[] salt = new byte[16];
+        inputStream.readFully(salt);
+
+        return new BackupFileHeader(app,Jid.of(jid),timestamp,iv,salt);
+
+    }
+
+    public byte[] getSalt() {
+        return salt;
+    }
+
+    public byte[] getIv() {
+        return iv;
+    }
+
+    public Jid getJid() {
+        return jid;
+    }
+
+    public String getApp() {
+        return app;
+    }
+
+    public long getTimestamp() {
+        return timestamp;
+    }
+}
--- a/src/main/res/drawable-hdpi/ic_archive_white_24dp.png
+++ b/src/main/res/drawable-hdpi/ic_archive_white_24dp.png
--- a/src/main/res/drawable-hdpi/ic_import_export_white_24dp.png
+++ b/src/main/res/drawable-hdpi/ic_import_export_white_24dp.png
--- a/src/main/res/drawable-mdpi/ic_archive_white_24dp.png
+++ b/src/main/res/drawable-mdpi/ic_archive_white_24dp.png
--- a/src/main/res/drawable-mdpi/ic_import_export_white_24dp.png
+++ b/src/main/res/drawable-mdpi/ic_import_export_white_24dp.png
--- a/src/main/res/drawable-xhdpi/ic_archive_white_24dp.png
+++ b/src/main/res/drawable-xhdpi/ic_archive_white_24dp.png
--- a/src/main/res/drawable-xhdpi/ic_import_export_white_24dp.png
+++ b/src/main/res/drawable-xhdpi/ic_import_export_white_24dp.png
--- a/src/main/res/drawable-xxhdpi/ic_archive_white_24dp.png
+++ b/src/main/res/drawable-xxhdpi/ic_archive_white_24dp.png
--- a/src/main/res/drawable-xxhdpi/ic_import_export_white_24dp.png
+++ b/src/main/res/drawable-xxhdpi/ic_import_export_white_24dp.png
--- a/src/main/res/drawable-xxxhdpi/ic_archive_white_24dp.png
+++ b/src/main/res/drawable-xxxhdpi/ic_archive_white_24dp.png
--- a/src/main/res/drawable-xxxhdpi/ic_import_export_white_24dp.png
+++ b/src/main/res/drawable-xxxhdpi/ic_import_export_white_24dp.png
--- a/src/main/res/layout/account_row.xml
+++ b/src/main/res/layout/account_row.xml
@ -1,9 +1,11 @@
 <?xml version="1.0" encoding="utf-8"?>
-<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
-                xmlns:app="http://schemas.android.com/apk/res-auto"
+<layout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
-                android:background="?android:attr/activatedBackgroundIndicator"
+        android:background="?android:selectableItemBackground"
        android:paddingLeft="8dp"
        android:paddingBottom="8dp"
        android:paddingTop="8dp">
@ -32,15 +34,14 @@
                android:layout_height="wrap_content"
                android:scrollHorizontally="false"
                android:singleLine="true"
-            android:textAppearance="@style/TextAppearance.Conversations.Subhead"/>
+                android:textAppearance="@style/TextAppearance.Conversations.Subhead" />

            <TextView
                android:id="@+id/account_status"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/account_status_unknown"
-            android:textAppearance="@style/TextAppearance.Conversations.Body2"
-             />
+                android:textAppearance="@style/TextAppearance.Conversations.Body2" />
        </LinearLayout>

        <android.support.v7.widget.SwitchCompat
@ -50,6 +51,7 @@
            android:layout_alignParentRight="true"
            android:layout_centerVertical="true"
            android:padding="16dp"
-        android:focusable="false"/>
+            android:focusable="false" />

-</RelativeLayout>
+    </RelativeLayout>
+</layout>
--- a/src/main/res/layout/dialog_quickedit.xml
+++ b/src/main/res/layout/dialog_quickedit.xml
@ -6,9 +6,7 @@
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
-        android:paddingLeft="?attr/dialog_horizontal_padding"
-        android:paddingRight="?attr/dialog_horizontal_padding"
-        android:paddingTop="?attr/dialog_vertical_padding">
+        android:padding="?dialogPreferredPadding">

        <android.support.design.widget.TextInputLayout
            android:id="@+id/input_layout"
--- a/src/main/res/values/strings.xml
+++ b/src/main/res/values/strings.xml
@ -314,9 +314,12 @@
    <string name="try_again">Try again</string>
    <string name="pref_keep_foreground_service">Keep service in foreground</string>
    <string name="pref_keep_foreground_service_summary">Prevents the operating system from killing your connection</string>
-    <string name="pref_export_logs">Export history</string>
-    <string name="pref_export_logs_summary">Write conversations history logs to SD card</string>
-    <string name="notification_export_logs_title">Writing logs to SD card</string>
+    <string name="pref_create_backup">Create backup</string>
+    <string name="pref_create_backup_summary">Write backup files to %s</string>
+    <string name="notification_create_backup_title">Creating backup files</string>
+    <string name="notification_restore_backup_title">Restoring backup</string>
+    <string name="notification_restored_backup_title">Your backup has been restored</string>
+    <string name="notification_restored_backup_subtitle">Do not forget to enable the account.</string>
    <string name="choose_file">Choose file</string>
    <string name="receiving_x_file">Receiving %1$s (%2$d%% completed)</string>
    <string name="download_x_file">Download %s</string>
@ -747,7 +750,6 @@
    <string name="video_compression_channel_name">Video compression</string>
    <string name="view_media">View media</string>
    <string name="media_browser">Media browser</string>
-    <string name="export_channel_name">History export</string>
    <string name="security_violation_not_attaching_file">File omitted due to security violation.</string>
    <string name="pref_video_compression">Video Quality</string>
    <string name="pref_video_compression_summary">Lower quality means smaller files</string>
@ -811,4 +813,11 @@
    <string name="open_with">Open with…</string>
    <string name="set_profile_picture">Conversations profile picture</string>
    <string name="choose_account">Choose account</string>
+    <string name="restore_backup">Restore backup</string>
+    <string name="restore">Restore</string>
+    <string name="enter_password_to_restore">Enter your password for the account %s to restore the backup.</string>
+    <string name="restore_warning">Do not use the restore backup feature in an attempt to clone (run simultaneously) an installation. Restoring a backup is only meant for migrations or in case you’ve lost the original device.</string>
+    <string name="unable_to_restore_backup">Unable to restore backup</string>
+    <string name="unable_to_decrypt_backup">Unable to decrypt backup</string>
+    <string name="backup_channel_name"><![CDATA[Backup & Restore]]></string>
 </resources>
--- a/src/main/res/values/themes.xml
+++ b/src/main/res/values/themes.xml
@ -95,7 +95,6 @@
        <item type="reference" name="icon_search">@drawable/ic_search_white_24dp</item>
        <item type="reference" name="icon_secure">@drawable/ic_lock_open_white_24dp</item>
        <item type="reference" name="icon_settings">@drawable/ic_settings_black_24dp</item>
-        <item type="reference" name="icon_import_export">@drawable/ic_import_export_white_24dp</item>
        <item type="reference" name="icon_share">@drawable/ic_share_white_24dp</item>
        <item type="reference" name="icon_scan_qr_code">@drawable/ic_qr_code_scan_white_24dp</item>
        <item type="reference" name="icon_scroll_down">@drawable/ic_scroll_to_end_black</item>
@ -208,7 +207,6 @@
        <item type="reference" name="icon_search">@drawable/ic_search_white_24dp</item>
        <item type="reference" name="icon_secure">@drawable/ic_lock_open_white_24dp</item>
        <item type="reference" name="icon_settings">@drawable/ic_settings_white_24dp</item>
-        <item type="reference" name="icon_import_export">@drawable/ic_import_export_white_24dp</item>
        <item type="reference" name="icon_share">@drawable/ic_share_white_24dp</item>
        <item type="reference" name="icon_scan_qr_code">@drawable/ic_qr_code_scan_white_24dp</item>
        <item type="reference" name="icon_scroll_down">@drawable/ic_scroll_to_end_white</item>
--- a/src/main/res/xml/preferences.xml
+++ b/src/main/res/xml/preferences.xml
@ -330,9 +330,9 @@
                    android:summary="@string/pref_keep_foreground_service_summary"
                    android:title="@string/pref_keep_foreground_service" />
                <Preference
-                    android:key="export_logs"
-                    android:summary="@string/pref_export_logs_summary"
-                    android:title="@string/pref_export_logs" />
+                    android:key="create_backup"
+                    android:summary="@string/pref_create_backup_summary"
+                    android:title="@string/pref_create_backup" />
            </PreferenceCategory>
        </PreferenceScreen>