Refactor the database classes to be more reusable

app/src/main/java/me/impy/aegis/crypto/CryptParameters.java

@@ -30,7 +30,7 @@ public class CryptParameters implements Serializable {
         return obj;
     }
 
-    public static CryptParameters parseJson(JSONObject obj) throws JSONException, HexException {
+    public static CryptParameters fromJson(JSONObject obj) throws JSONException, HexException {
         byte[] nonce = Hex.decode(obj.getString("nonce"));
         byte[] tag = Hex.decode(obj.getString("tag"));
         return new CryptParameters(nonce, tag);

app/src/main/java/me/impy/aegis/db/Database.java

@@ -12,14 +12,13 @@ import me.impy.aegis.otp.OtpInfoException;
 
 public class Database {
     private static final int VERSION = 1;
-
     private DatabaseEntryList _entries = new DatabaseEntryList();
 
-    public JSONObject serialize() {
+    public JSONObject toJson() {
         try {
             JSONArray array = new JSONArray();
             for (DatabaseEntry e : _entries) {
-                array.put(e.serialize());
+                array.put(e.toJson());
             }
 
             JSONObject obj = new JSONObject();
@@ -31,8 +30,9 @@ public class Database {
         }
     }
 
-    public void deserialize(JSONObject obj) throws DatabaseException {
+    public static Database fromJson(JSONObject obj) throws DatabaseException {
-        // TODO: support different VERSION deserialization providers
+        Database db = new Database();
+
         try {
             int ver = obj.getInt("version");
             if (ver != VERSION) {
@@ -41,13 +41,14 @@ public class Database {
 
             JSONArray array = obj.getJSONArray("entries");
             for (int i = 0; i < array.length(); i++) {
-                DatabaseEntry entry = new DatabaseEntry(null);
+                DatabaseEntry entry = DatabaseEntry.fromJson(array.getJSONObject(i));
-                entry.deserialize(array.getJSONObject(i));
+                db.addEntry(entry);
-                addEntry(entry);
             }
         } catch (Base64Exception | OtpInfoException | JSONException e) {
             throw new DatabaseException(e);
         }
+
+        return db;
     }
 
     public void addEntry(DatabaseEntry entry) {

app/src/main/java/me/impy/aegis/db/DatabaseEntry.java

@@ -9,6 +9,7 @@ import java.util.UUID;
 
 import me.impy.aegis.encoding.Base64;
 import me.impy.aegis.encoding.Base64Exception;
+import me.impy.aegis.otp.GoogleAuthInfo;
 import me.impy.aegis.otp.OtpInfo;
 import me.impy.aegis.otp.OtpInfoException;
 
@@ -19,9 +20,13 @@ public class DatabaseEntry implements Serializable {
     private OtpInfo _info;
     private byte[] _icon;
 
-    public DatabaseEntry(OtpInfo info) {
+    private DatabaseEntry(UUID uuid, OtpInfo info) {
+        _uuid = uuid;
         _info = info;
-        _uuid = UUID.randomUUID();
+    }
+
+    public DatabaseEntry(OtpInfo info) {
+        this(UUID.randomUUID(), info);
     }
 
     public DatabaseEntry(OtpInfo info, String name, String issuer) {
@@ -30,7 +35,11 @@ public class DatabaseEntry implements Serializable {
         setIssuer(issuer);
     }
 
-    public JSONObject serialize() {
+    public DatabaseEntry(GoogleAuthInfo info) {
+        this(info.getOtpInfo(), info.getAccountName(), info.getIssuer());
+    }
+
+    public JSONObject toJson() {
         JSONObject obj = new JSONObject();
 
         try {
@@ -47,22 +56,26 @@ public class DatabaseEntry implements Serializable {
         return obj;
     }
 
-    public void deserialize(JSONObject obj) throws JSONException, OtpInfoException, Base64Exception {
+    public static DatabaseEntry fromJson(JSONObject obj) throws JSONException, OtpInfoException, Base64Exception {
         // if there is no uuid, generate a new one
+        UUID uuid;
         if (!obj.has("uuid")) {
-            _uuid = UUID.randomUUID();
+            uuid = UUID.randomUUID();
         } else {
-            _uuid = UUID.fromString(obj.getString("uuid"));
+            uuid = UUID.fromString(obj.getString("uuid"));
         }
-        _name = obj.getString("name");
+
-        _issuer = obj.getString("issuer");
+        OtpInfo info = OtpInfo.fromJson(obj.getString("type"), obj.getJSONObject("info"));
+        DatabaseEntry entry = new DatabaseEntry(uuid, info);
+        entry.setName(obj.getString("name"));
+        entry.setIssuer(obj.getString("issuer"));
 
         Object icon = obj.get("icon");
         if (icon != JSONObject.NULL) {
-            _icon = Base64.decode((String) icon);
+            entry.setIcon(Base64.decode((String) icon));
         }
 
-        _info = OtpInfo.parseJson(obj.getString("type"), obj.getJSONObject("info"));
+        return entry;
     }
 
     public void resetUUID() {

app/src/main/java/me/impy/aegis/db/DatabaseFile.java

@@ -1,6 +1,5 @@
 package me.impy.aegis.db;
 
-import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
@@ -8,7 +7,6 @@ import java.io.UnsupportedEncodingException;
 
 import me.impy.aegis.crypto.CryptParameters;
 import me.impy.aegis.crypto.CryptResult;
-import me.impy.aegis.crypto.MasterKey;
 import me.impy.aegis.crypto.MasterKeyException;
 import me.impy.aegis.db.slots.SlotList;
 import me.impy.aegis.db.slots.SlotListException;
@@ -20,22 +18,41 @@ public class DatabaseFile {
     public static final byte VERSION = 1;
 
     private Object _content;
-    private CryptParameters _cryptParameters;
+    private Header _header;
-    private SlotList _slots;
 
-    public byte[] serialize() {
+    public DatabaseFile() {
+
+    }
+
+    private DatabaseFile(Object content, Header header) {
+        _content = content;
+        _header = header;
+    }
+
+    public Header getHeader() {
+        return _header;
+    }
+
+    public boolean isEncrypted() {
+        return !_header.isEmpty();
+    }
+
+    public JSONObject toJson() {
         try {
-            // don't write the crypt parameters and slots if the content is not encrypted
-            boolean plain = _content instanceof JSONObject || !isEncrypted();
-            JSONObject headerObj = new JSONObject();
-            headerObj.put("slots", plain ? JSONObject.NULL : SlotList.serialize(_slots));
-            headerObj.put("params", plain ? JSONObject.NULL : _cryptParameters.toJson());
-
             JSONObject obj = new JSONObject();
             obj.put("version", VERSION);
-            obj.put("header", headerObj);
+            obj.put("header", _header.toJson());
             obj.put("db", _content);
+            return obj;
+        } catch (JSONException e) {
+            throw new RuntimeException(e);
+        }
+    }
 
+    public byte[] toBytes() {
+        JSONObject obj = toJson();
+
+        try {
             String string = obj.toString(4);
             return string.getBytes("UTF-8");
         } catch (JSONException | UnsupportedEncodingException e) {
@@ -43,76 +60,108 @@ public class DatabaseFile {
         }
     }
 
-    public void deserialize(byte[] data) throws DatabaseFileException {
+    public static DatabaseFile fromJson(JSONObject obj) throws DatabaseFileException {
         try {
-            JSONObject obj = new JSONObject(new String(data, "UTF-8"));
-            JSONObject headerObj = obj.getJSONObject("header");
             if (obj.getInt("version") > VERSION) {
                 throw new DatabaseFileException("unsupported version");
             }
 
-            JSONArray slotObj = headerObj.optJSONArray("slots");
+            Header header = Header.fromJson(obj.getJSONObject("header"));
-            if (slotObj != null) {
+            if (!header.isEmpty()) {
-                _slots = SlotList.deserialize(slotObj);
+                return new DatabaseFile(obj.getString("db"), header);
             }
 
-            JSONObject cryptObj = headerObj.optJSONObject("params");
+            return new DatabaseFile(obj.getJSONObject("db"), header);
-            if (cryptObj != null) {
+        } catch (JSONException e) {
-                _cryptParameters = CryptParameters.parseJson(cryptObj);
-            }
-
-            if (cryptObj == null || slotObj == null) {
-                _content = obj.getJSONObject("db");
-            } else {
-                _content = obj.getString("db");
-            }
-        } catch (SlotListException | UnsupportedEncodingException | JSONException | HexException e) {
             throw new DatabaseFileException(e);
         }
     }
 
-    public boolean isEncrypted() {
+    public static DatabaseFile fromBytes(byte[] data) throws DatabaseFileException {
-        return _slots != null;
+        try {
+            JSONObject obj = new JSONObject(new String(data, "UTF-8"));
+            return DatabaseFile.fromJson(obj);
+        } catch (UnsupportedEncodingException | JSONException e) {
+            throw new DatabaseFileException(e);
+        }
     }
 
     public JSONObject getContent() {
         return (JSONObject) _content;
     }
 
-    public JSONObject getContent(MasterKey key) throws DatabaseFileException {
+    public JSONObject getContent(DatabaseFileCredentials creds) throws DatabaseFileException {
         try {
             byte[] bytes = Base64.decode((String) _content);
-            CryptResult result = key.decrypt(bytes, _cryptParameters);
+            CryptResult result = creds.decrypt(bytes, _header.getParams());
             return new JSONObject(new String(result.getData(), "UTF-8"));
         } catch (MasterKeyException | JSONException | UnsupportedEncodingException | Base64Exception e) {
             throw new DatabaseFileException(e);
         }
     }
 
-    public void setContent(JSONObject dbObj) {
+    public void setContent(JSONObject obj) {
-        _content = dbObj;
+        _content = obj;
-        _cryptParameters = null;
+        _header = new Header(null, null);
-        _slots = null;
     }
 
-    public void setContent(JSONObject dbObj, MasterKey key) throws DatabaseFileException {
+    public void setContent(JSONObject obj, DatabaseFileCredentials creds) throws DatabaseFileException {
         try {
-            String string = dbObj.toString(4);
+            String string = obj.toString(4);
             byte[] dbBytes = string.getBytes("UTF-8");
 
-            CryptResult result = key.encrypt(dbBytes);
+            CryptResult result = creds.encrypt(dbBytes);
             _content = Base64.encode(result.getData());
-            _cryptParameters = result.getParams();
+            _header = new Header(creds.getSlots(), result.getParams());
         } catch (MasterKeyException | UnsupportedEncodingException | JSONException e) {
             throw new DatabaseFileException(e);
         }
     }
 
-    public SlotList getSlots() {
+    public static class Header {
-        return _slots;
+        private SlotList _slots;
-    }
+        private CryptParameters _params;
 
-    public void setSlots(SlotList slots) {
+        public Header(SlotList slots, CryptParameters params) {
-        _slots = slots;
+            _slots = slots;
+            _params = params;
+        }
+
+        public static Header fromJson(JSONObject obj) throws DatabaseFileException {
+            if (obj.isNull("slots") && obj.isNull("params")) {
+                return new Header(null, null);
+            }
+
+            try {
+                SlotList slots = SlotList.fromJson(obj.getJSONArray("slots"));
+                CryptParameters params = CryptParameters.fromJson(obj.getJSONObject("params"));
+                return new Header(slots, params);
+            } catch (SlotListException | JSONException | HexException e) {
+                throw new DatabaseFileException(e);
+            }
+        }
+
+        public JSONObject toJson() {
+            try {
+                JSONObject obj = new JSONObject();
+                obj.put("slots", _slots != null ? _slots.toJson() : JSONObject.NULL);
+                obj.put("params", _params != null ? _params.toJson() : JSONObject.NULL);
+                return obj;
+            } catch (JSONException e) {
+                throw new RuntimeException(e);
+            }
+        }
+
+        public SlotList getSlots() {
+            return _slots;
+        }
+
+        public CryptParameters getParams() {
+            return _params;
+        }
+
+        public boolean isEmpty() {
+            return _slots == null && _params == null;
+        }
     }
 }

app/src/main/java/me/impy/aegis/db/DatabaseFileCredentials.java

@@ -0,0 +1,40 @@
+package me.impy.aegis.db;
+
+import java.io.Serializable;
+
+import me.impy.aegis.crypto.CryptParameters;
+import me.impy.aegis.crypto.CryptResult;
+import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.crypto.MasterKeyException;
+import me.impy.aegis.db.slots.SlotList;
+
+public class DatabaseFileCredentials implements Serializable {
+    private MasterKey _key;
+    private SlotList _slots;
+
+    public DatabaseFileCredentials() {
+        _key = MasterKey.generate();
+        _slots = new SlotList();
+    }
+
+    public DatabaseFileCredentials(MasterKey key, SlotList slots) {
+        _key = key;
+        _slots = slots;
+    }
+
+    public CryptResult encrypt(byte[] bytes) throws MasterKeyException {
+        return _key.encrypt(bytes);
+    }
+
+    public CryptResult decrypt(byte[] bytes, CryptParameters params) throws MasterKeyException {
+        return _key.decrypt(bytes, params);
+    }
+
+    public MasterKey getKey() {
+        return _key;
+    }
+
+    public SlotList getSlots() {
+        return _slots;
+    }
+}

app/src/main/java/me/impy/aegis/db/DatabaseManager.java

@@ -14,17 +14,17 @@ import java.util.List;
 import java.util.UUID;
 
 import me.impy.aegis.BuildConfig;
-import me.impy.aegis.crypto.MasterKey;
-import me.impy.aegis.db.slots.SlotList;
 
 public class DatabaseManager {
     private static final String FILENAME = "aegis.json";
     private static final String FILENAME_EXPORT = "aegis_export.json";
     private static final String FILENAME_EXPORT_PLAIN = "aegis_export_plain.json";
 
-    private MasterKey _key;
-    private DatabaseFile _file;
     private Database _db;
+    private DatabaseFile _file;
+    private DatabaseFileCredentials _creds;
+    private boolean _encrypt;
+
     private Context _context;
 
     public DatabaseManager(Context context) {
@@ -39,31 +39,17 @@ public class DatabaseManager {
     public void load() throws DatabaseManagerException {
         assertState(true, false);
 
-        try {
+        try (FileInputStream file = _context.openFileInput(FILENAME)) {
-            byte[] fileBytes;
+            byte[] fileBytes = new byte[(int) file.getChannel().size()];
-            FileInputStream file = null;
+            DataInputStream stream = new DataInputStream(file);
+            stream.readFully(fileBytes);
+            stream.close();
 
-            try {
+            _file = DatabaseFile.fromBytes(fileBytes);
-                file = _context.openFileInput(FILENAME);
+            _encrypt = _file.isEncrypted();
-                fileBytes = new byte[(int) file.getChannel().size()];
+            if (!isEncryptionEnabled()) {
-                DataInputStream stream = new DataInputStream(file);
-                stream.readFully(fileBytes);
-                stream.close();
-            } finally {
-                // always close the file stream
-                // there is no need to close the DataInputStream
-                if (file != null) {
-                    file.close();
-                }
-            }
-
-            _file = new DatabaseFile();
-            _file.deserialize(fileBytes);
-
-            if (!_file.isEncrypted()) {
                 JSONObject obj = _file.getContent();
-                _db = new Database();
+                _db = Database.fromJson(obj);
-                _db.deserialize(obj);
             }
         } catch (IOException | DatabaseFileException | DatabaseException e) {
             throw new DatabaseManagerException(e);
@@ -73,37 +59,26 @@ public class DatabaseManager {
     public void lock() {
         assertState(false, true);
         // TODO: properly clear everything
-        _key = null;
+        _creds = null;
         _db = null;
     }
 
-    public void unlock(MasterKey key) throws DatabaseManagerException {
+    public void unlock(DatabaseFileCredentials creds) throws DatabaseManagerException {
         assertState(true, true);
 
         try {
-            JSONObject obj = _file.getContent(key);
+            JSONObject obj = _file.getContent(creds);
-            _db = new Database();
+            _db = Database.fromJson(obj);
-            _db.deserialize(obj);
+            _creds = creds;
-            _key = key;
         } catch (DatabaseFileException | DatabaseException e) {
             throw new DatabaseManagerException(e);
         }
     }
 
     public static void save(Context context, DatabaseFile file) throws DatabaseManagerException {
-        try {
+        byte[] bytes = file.toBytes();
-            byte[] bytes = file.serialize();
+        try (FileOutputStream stream = context.openFileOutput(FILENAME, Context.MODE_PRIVATE)) {
-
+            stream.write(bytes);
-            FileOutputStream stream = null;
-            try {
-                stream = context.openFileOutput(FILENAME, Context.MODE_PRIVATE);
-                stream.write(bytes);
-            } finally {
-                // always close the file stream
-                if (stream != null) {
-                    stream.close();
-                }
-            }
         } catch (IOException e) {
             throw new DatabaseManagerException(e);
         }
@@ -113,9 +88,9 @@ public class DatabaseManager {
         assertState(false, true);
 
         try {
-            JSONObject obj = _db.serialize();
+            JSONObject obj = _db.toJson();
-            if (_file.isEncrypted()) {
+            if (isEncryptionEnabled()) {
-                _file.setContent(obj, _key);
+                _file.setContent(obj, _creds);
             } else {
                 _file.setContent(obj);
             }
@@ -130,31 +105,22 @@ public class DatabaseManager {
 
         try {
             DatabaseFile dbFile = new DatabaseFile();
-            dbFile.setSlots(_file.getSlots());
+            if (encrypt && isEncryptionEnabled()) {
-            if (encrypt && getFile().isEncrypted()) {
+                dbFile.setContent(_db.toJson(), _creds);
-                dbFile.setContent(_db.serialize(), _key);
             } else {
-                dbFile.setContent(_db.serialize());
+                dbFile.setContent(_db.toJson());
             }
 
-            File file;
+            String dirName = !BuildConfig.DEBUG ? "Aegis" : "AegisDebug";
-            FileOutputStream stream = null;
+            File dir = new File(Environment.getExternalStorageDirectory(), dirName);
-            try {
+            if (!dir.exists() && !dir.mkdirs()) {
-                String dirName = !BuildConfig.DEBUG ? "Aegis" : "AegisDebug";
+                throw new IOException("error creating external storage directory");
-                File dir = new File(Environment.getExternalStorageDirectory(), dirName);
+            }
-                if (!dir.exists() && !dir.mkdirs()) {
-                    throw new IOException("error creating external storage directory");
-                }
 
-                byte[] bytes = dbFile.serialize();
+            byte[] bytes = dbFile.toBytes();
-                file = new File(dir.getAbsolutePath(), encrypt ? FILENAME_EXPORT : FILENAME_EXPORT_PLAIN);
+            File file = new File(dir.getAbsolutePath(), encrypt ? FILENAME_EXPORT : FILENAME_EXPORT_PLAIN);
-                stream = new FileOutputStream(file);
+            try (FileOutputStream stream = new FileOutputStream(file)) {
                 stream.write(bytes);
-            } finally {
-                // always close the file stream
-                if (stream != null) {
-                    stream.close();
-                }
             }
 
             return file.getAbsolutePath();
@@ -193,25 +159,38 @@ public class DatabaseManager {
         return _db.getEntryByUUID(uuid);
     }
 
-    public MasterKey getMasterKey() {
+    public DatabaseFileCredentials getCredentials() {
         assertState(false, true);
-        return _key;
+        return _creds;
     }
 
-    public DatabaseFile getFile() {
+    public void setCredentials(DatabaseFileCredentials creds) {
-        return _file;
+        assertState(false, true);
+        _creds = creds;
     }
 
-    public void enableEncryption(MasterKey key, SlotList slots) {
+    public DatabaseFile.Header getFileHeader() {
-        assertState(false, true);
+        assertLoaded(true);
-        _key = key;
+        return _file.getHeader();
-        _file.setSlots(slots);
     }
 
-    public void disableEncryption() {
+    public boolean isEncryptionEnabled() {
+        assertLoaded(true);
+        return _encrypt;
+    }
+
+    public void enableEncryption(DatabaseFileCredentials creds) throws DatabaseManagerException {
         assertState(false, true);
-        _key = null;
+        _creds = creds;
-        _file.setSlots(null);
+        _encrypt = true;
+        save();
+    }
+
+    public void disableEncryption() throws DatabaseManagerException {
+        assertState(false, true);
+        _creds = null;
+        _encrypt = false;
+        save();
     }
 
     public boolean isLoaded() {
@@ -223,16 +202,20 @@ public class DatabaseManager {
     }
 
     private void assertState(boolean locked, boolean loaded) {
-        if (isLoaded() && !loaded) {
+        assertLoaded(loaded);
-            throw new AssertionError("database file has not been loaded yet");
-        } else if (!isLoaded() && loaded) {
-            throw new AssertionError("database file has is already been loaded");
-        }
 
         if (isLocked() && !locked) {
             throw new AssertionError("database file has not been unlocked yet");
         } else if (!isLocked() && locked) {
-            throw new AssertionError("database file has is already been unlocked");
+            throw new AssertionError("database file has already been unlocked");
+        }
+    }
+
+    private void assertLoaded(boolean loaded) {
+        if (isLoaded() && !loaded) {
+            throw new AssertionError("database file has already been loaded");
+        } else if (!isLoaded() && loaded) {
+            throw new AssertionError("database file has not been loaded yet");
         }
     }
 }

app/src/main/java/me/impy/aegis/db/slots/PasswordSlot.java

@@ -20,9 +20,9 @@ public class PasswordSlot extends RawSlot {
     }
 
     @Override
-    public JSONObject serialize() {
+    public JSONObject toJson() {
         try {
-            JSONObject obj = super.serialize();
+            JSONObject obj = super.toJson();
             obj.put("n", _n);
             obj.put("r", _r);
             obj.put("p", _p);

app/src/main/java/me/impy/aegis/db/slots/Slot.java

@@ -10,7 +10,6 @@ import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.util.UUID;
 
-import javax.crypto.AEADBadTagException;
 import javax.crypto.BadPaddingException;
 import javax.crypto.Cipher;
 import javax.crypto.IllegalBlockSizeException;
@@ -85,7 +84,7 @@ public abstract class Slot implements Serializable {
         }
     }
 
-    public JSONObject serialize() {
+    public JSONObject toJson() {
         try {
             JSONObject obj = new JSONObject();
             JSONObject paramObj = _encryptedMasterKeyParams.toJson();
@@ -114,7 +113,7 @@ public abstract class Slot implements Serializable {
 
             JSONObject paramObj = obj.getJSONObject("key_params");
             _encryptedMasterKey = Hex.decode(obj.getString("key"));
-            _encryptedMasterKeyParams = CryptParameters.parseJson(paramObj);
+            _encryptedMasterKeyParams = CryptParameters.fromJson(paramObj);
         } catch (JSONException | HexException e) {
             throw new SlotException(e);
         }

app/src/main/java/me/impy/aegis/db/slots/SlotList.java

@@ -12,16 +12,16 @@ import java.util.List;
 public class SlotList implements Iterable<Slot>, Serializable {
     private List<Slot> _slots = new ArrayList<>();
 
-    public static JSONArray serialize(SlotList slots) {
+    public JSONArray toJson() {
         JSONArray array = new JSONArray();
-        for (Slot slot : slots) {
+        for (Slot slot : this) {
-            array.put(slot.serialize());
+            array.put(slot.toJson());
         }
 
         return array;
     }
 
-    public static SlotList deserialize(JSONArray array) throws SlotListException {
+    public static SlotList fromJson(JSONArray array) throws SlotListException {
         SlotList slots = new SlotList();
 
         try {

app/src/main/java/me/impy/aegis/importers/AegisImporter.java

@@ -4,16 +4,16 @@ import org.json.JSONObject;
 
 import java.util.List;
 
-import me.impy.aegis.crypto.MasterKey;
 import me.impy.aegis.db.Database;
 import me.impy.aegis.db.DatabaseEntry;
 import me.impy.aegis.db.DatabaseException;
 import me.impy.aegis.db.DatabaseFile;
+import me.impy.aegis.db.DatabaseFileCredentials;
 import me.impy.aegis.db.DatabaseFileException;
 import me.impy.aegis.util.ByteInputStream;
 
 public class AegisImporter extends DatabaseImporter {
-    private MasterKey _key;
+    private DatabaseFileCredentials _creds;
     private DatabaseFile _file;
 
     public AegisImporter(ByteInputStream stream) {
@@ -24,8 +24,7 @@ public class AegisImporter extends DatabaseImporter {
     public void parse() throws DatabaseImporterException {
         try {
             byte[] bytes = _stream.getBytes();
-            _file = new DatabaseFile();
+            _file = DatabaseFile.fromBytes(bytes);
-            _file.deserialize(bytes);
         } catch (DatabaseFileException e) {
             throw new DatabaseImporterException(e);
         }
@@ -35,14 +34,13 @@ public class AegisImporter extends DatabaseImporter {
     public List<DatabaseEntry> convert() throws DatabaseImporterException {
         try {
             JSONObject obj;
-            if (_file.isEncrypted() && _key != null) {
+            if (_file.isEncrypted() && _creds != null) {
-                obj = _file.getContent(_key);
+                obj = _file.getContent(_creds);
             } else {
                 obj = _file.getContent();
             }
 
-            Database db = new Database();
+            Database db = Database.fromJson(obj);
-            db.deserialize(obj);
             return db.getEntries();
         } catch (DatabaseException | DatabaseFileException e) {
             throw new DatabaseImporterException(e);
@@ -54,8 +52,8 @@ public class AegisImporter extends DatabaseImporter {
         return _file.isEncrypted();
     }
 
-    public void setKey(MasterKey key) {
+    public void setCredentials(DatabaseFileCredentials creds) {
-        _key = key;
+        _creds = creds;
     }
 
     public DatabaseFile getFile() {

app/src/main/java/me/impy/aegis/importers/DatabaseImporter.java

@@ -42,14 +42,6 @@ public abstract class DatabaseImporter {
         }
     }
 
-    public static List<DatabaseImporter> create(ByteInputStream stream) {
-        List<DatabaseImporter> list = new ArrayList<>();
-        for (Class<? extends DatabaseImporter> type : _importers.values()) {
-            list.add(create(stream, type));
-        }
-        return list;
-    }
-
     public static Map<String, Class<? extends DatabaseImporter>> getImporters() {
         return _importers;
     }

app/src/main/java/me/impy/aegis/otp/OtpInfo.java

@@ -88,7 +88,7 @@ public abstract class OtpInfo implements Serializable {
         _digits = digits;
     }
 
-    public static OtpInfo parseJson(String type, JSONObject obj) throws OtpInfoException {
+    public static OtpInfo fromJson(String type, JSONObject obj) throws OtpInfoException {
         OtpInfo info;
 
         try {

app/src/main/java/me/impy/aegis/ui/AuthActivity.java

@@ -25,6 +25,7 @@ import me.impy.aegis.R;
 import me.impy.aegis.crypto.KeyStoreHandle;
 import me.impy.aegis.crypto.KeyStoreHandleException;
 import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.db.DatabaseFileCredentials;
 import me.impy.aegis.db.slots.FingerprintSlot;
 import me.impy.aegis.db.slots.PasswordSlot;
 import me.impy.aegis.db.slots.Slot;
@@ -128,7 +129,7 @@ public class AuthActivity extends AegisActivity implements FingerprintUiHelper.C
     private void setKey(MasterKey key) {
         // send the master key back to the main activity
         Intent result = new Intent();
-        result.putExtra("key", key);
+        result.putExtra("creds", new DatabaseFileCredentials(key, _slots));
         setResult(RESULT_OK, result);
         finish();
     }

app/src/main/java/me/impy/aegis/ui/IntroActivity.java

@@ -16,7 +16,7 @@ import javax.crypto.SecretKey;
 
 import me.impy.aegis.Preferences;
 import me.impy.aegis.R;
-import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.db.DatabaseFileCredentials;
 import me.impy.aegis.db.DatabaseFileException;
 import me.impy.aegis.db.DatabaseManagerException;
 import me.impy.aegis.db.slots.FingerprintSlot;
@@ -128,9 +128,9 @@ public class IntroActivity extends AppIntro2 implements DerivationTask.Callback
         }
 
         // generate the master key
-        MasterKey masterKey = null;
+        DatabaseFileCredentials creds = null;
         if (cryptType != CustomAuthenticationSlide.CRYPT_TYPE_NONE) {
-            masterKey = MasterKey.generate();
+            creds = new DatabaseFileCredentials();
         }
 
         SlotList slots = null;
@@ -141,10 +141,8 @@ public class IntroActivity extends AppIntro2 implements DerivationTask.Callback
                 throw new RuntimeException();
             }
             try {
-                _passwordSlot.setKey(masterKey, _passwordCipher);
+                _passwordSlot.setKey(creds.getKey(), _passwordCipher);
-                slots = new SlotList();
+                creds.getSlots().add(_passwordSlot);
-                slots.add(_passwordSlot);
-                _databaseFile.setSlots(slots);
             } catch (SlotException e) {
                 setException(e);
             }
@@ -156,8 +154,8 @@ public class IntroActivity extends AppIntro2 implements DerivationTask.Callback
                 // and add it to the list of slots
                 FingerprintSlot slot = _authenticatedSlide.getFingerSlot();
                 Cipher cipher = _authenticatedSlide.getFingerCipher();
-                slot.setKey(masterKey, cipher);
+                slot.setKey(creds.getKey(), cipher);
-                slots.add(slot);
+                creds.getSlots().add(slot);
             } catch (SlotException e) {
                 setException(e);
                 return;
@@ -166,11 +164,11 @@ public class IntroActivity extends AppIntro2 implements DerivationTask.Callback
 
         // finally, save the database
         try {
-            JSONObject obj = _database.serialize();
+            JSONObject obj = _database.toJson();
             if (cryptType == CustomAuthenticationSlide.CRYPT_TYPE_NONE) {
                 _databaseFile.setContent(obj);
             } else {
-                _databaseFile.setContent(obj, masterKey);
+                _databaseFile.setContent(obj, creds);
             }
             DatabaseManager.save(getApplicationContext(), _databaseFile);
         } catch (DatabaseManagerException | DatabaseFileException e) {
@@ -180,7 +178,7 @@ public class IntroActivity extends AppIntro2 implements DerivationTask.Callback
 
         // send the master key back to the main activity
         Intent result = new Intent();
-        result.putExtra("key", masterKey);
+        result.putExtra("creds", creds);
         setResult(RESULT_OK, result);
 
         // skip the intro from now on

app/src/main/java/me/impy/aegis/ui/MainActivity.java

@@ -20,7 +20,7 @@ import java.lang.reflect.UndeclaredThrowableException;
 
 import me.impy.aegis.AegisApplication;
 import me.impy.aegis.R;
-import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.db.DatabaseFileCredentials;
 import me.impy.aegis.db.DatabaseManagerException;
 import me.impy.aegis.db.DatabaseEntry;
 import me.impy.aegis.db.DatabaseManager;
@@ -218,13 +218,13 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
             throw new UndeclaredThrowableException(e);
         }
 
-        MasterKey key = (MasterKey) data.getSerializableExtra("key");
+        DatabaseFileCredentials creds = (DatabaseFileCredentials) data.getSerializableExtra("creds");
-        unlockDatabase(key);
+        unlockDatabase(creds);
     }
 
     private void onDecryptResult(int resultCode, Intent intent) {
-        MasterKey key = (MasterKey) intent.getSerializableExtra("key");
+        DatabaseFileCredentials creds = (DatabaseFileCredentials) intent.getSerializableExtra("creds");
-        unlockDatabase(key);
+        unlockDatabase(creds);
 
         doShortcutActions();
     }
@@ -361,7 +361,7 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
         }
     }
 
-    private void unlockDatabase(MasterKey key) {
+    private void unlockDatabase(DatabaseFileCredentials creds) {
         if (_loaded) {
             return;
         }
@@ -371,15 +371,14 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
                 _db.load();
             }
             if (_db.isLocked()) {
-                if (key == null) {
+                if (creds == null) {
                     startAuthActivity();
                     return;
                 } else {
-                    _db.unlock(key);
+                    _db.unlock(creds);
                 }
             }
         } catch (DatabaseManagerException e) {
-            e.printStackTrace();
             Toast.makeText(this, "An error occurred while trying to load/decrypt the database", Toast.LENGTH_LONG).show();
             startAuthActivity();
             return;
@@ -396,7 +395,7 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
 
     private void startAuthActivity() {
         Intent intent = new Intent(this, AuthActivity.class);
-        intent.putExtra("slots", _db.getFile().getSlots());
+        intent.putExtra("slots", _db.getFileHeader().getSlots());
         startActivityForResult(intent, CODE_DECRYPT);
     }
 
@@ -404,7 +403,6 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
         try {
             _db.save();
         } catch (DatabaseManagerException e) {
-            e.printStackTrace();
             Toast.makeText(this, "An error occurred while trying to save the database", Toast.LENGTH_LONG).show();
         }
     }
@@ -413,7 +411,7 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
         // hide the lock icon if the database is not unlocked
         if (_menu != null && !_db.isLocked()) {
             MenuItem item = _menu.findItem(R.id.action_lock);
-            item.setVisible(_db.getFile().isEncrypted());
+            item.setVisible(_db.isEncryptionEnabled());
         }
     }
 

app/src/main/java/me/impy/aegis/ui/PreferencesFragment.java

@@ -26,12 +26,12 @@ import javax.crypto.Cipher;
 
 import me.impy.aegis.AegisApplication;
 import me.impy.aegis.R;
-import me.impy.aegis.crypto.MasterKey;
 import me.impy.aegis.db.DatabaseEntry;
+import me.impy.aegis.db.DatabaseFileCredentials;
+import me.impy.aegis.db.DatabaseFileException;
 import me.impy.aegis.db.DatabaseManager;
 import me.impy.aegis.db.DatabaseManagerException;
 import me.impy.aegis.db.slots.Slot;
-import me.impy.aegis.db.slots.SlotList;
 import me.impy.aegis.db.slots.SlotException;
 import me.impy.aegis.helpers.PermissionHelper;
 import me.impy.aegis.importers.AegisImporter;
@@ -138,7 +138,7 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
         _encryptionPreference.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
             @Override
             public boolean onPreferenceChange(Preference preference, Object newValue) {
-                if (!_db.getFile().isEncrypted()) {
+                if (!_db.isEncryptionEnabled()) {
                     PasswordDialogFragment dialog = new PasswordDialogFragment();
                     // TODO: find a less ugly way to obtain the fragment manager
                     dialog.show(getActivity().getSupportFragmentManager(), null);
@@ -148,8 +148,11 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
                             .setMessage("Are you sure you want to disable encryption? This will cause the database to be stored in plain text")
                             .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
                                 public void onClick(DialogInterface dialog, int which) {
-                                    _db.disableEncryption();
+                                    try {
-                                    saveDatabase();
+                                        _db.disableEncryption();
+                                    } catch (DatabaseManagerException e) {
+                                        Toast.makeText(getActivity(), "An error occurred while enabling encryption", Toast.LENGTH_SHORT).show();
+                                    }
                                     updateEncryptionPreference();
                                 }
                             })
@@ -163,10 +166,8 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
         _slotsPreference.setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
             @Override
             public boolean onPreferenceClick(Preference preference) {
-                MasterKey masterKey = _db.getMasterKey();
                 Intent intent = new Intent(getActivity(), SlotManagerActivity.class);
-                intent.putExtra("masterKey", masterKey);
+                intent.putExtra("creds", _db.getCredentials());
-                intent.putExtra("slots", _db.getFile().getSlots());
                 startActivityForResult(intent, CODE_SLOTS);
                 return true;
             }
@@ -249,13 +250,12 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
             return;
         }
 
-        MasterKey key = (MasterKey) data.getSerializableExtra("key");
+        DatabaseFileCredentials creds = (DatabaseFileCredentials) data.getSerializableExtra("creds");
-        ((AegisImporter)_importer).setKey(key);
+        ((AegisImporter)_importer).setCredentials(creds);
 
         try {
             importDatabase(_importer);
         } catch (DatabaseImporterException e) {
-            e.printStackTrace();
             Toast.makeText(getActivity(), "An error occurred while trying to parse the file", Toast.LENGTH_SHORT).show();
         }
 
@@ -269,25 +269,16 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
         }
 
         ByteInputStream stream;
-        InputStream fileStream = null;
 
-        try {
+        try (InputStream fileStream = getActivity().getContentResolver().openInputStream(uri)) {
-            fileStream = getActivity().getContentResolver().openInputStream(uri);
             stream = ByteInputStream.create(fileStream);
         } catch (FileNotFoundException e) {
             Toast.makeText(getActivity(), "Error: File not found", Toast.LENGTH_SHORT).show();
             return;
         } catch (IOException e) {
+            e.printStackTrace();
             Toast.makeText(getActivity(), "An error occurred while trying to read the file", Toast.LENGTH_SHORT).show();
             return;
-        } finally {
-            if (fileStream != null) {
-                try {
-                    fileStream.close();
-                } catch (IOException e) {
-                    e.printStackTrace();
-                }
-            }
         }
 
         try {
@@ -299,7 +290,7 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
                 _importer = importer;
 
                 Intent intent = new Intent(getActivity(), AuthActivity.class);
-                intent.putExtra("slots", ((AegisImporter)_importer).getFile().getSlots());
+                intent.putExtra("slots", ((AegisImporter)_importer).getFile().getHeader().getSlots());
                 startActivityForResult(intent, CODE_IMPORT_DECRYPT);
                 return;
             }
@@ -344,7 +335,6 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
                     try {
                         filename = _db.export(checked[0]);
                     } catch (DatabaseManagerException e) {
-                        e.printStackTrace();
                         Toast.makeText(getActivity(), "An error occurred while trying to export the database", Toast.LENGTH_SHORT).show();
                         return;
                     }
@@ -355,7 +345,7 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
                     Toast.makeText(getActivity(), "The database has been exported to: " + filename, Toast.LENGTH_SHORT).show();
                 })
                 .setNegativeButton(android.R.string.cancel, null);
-        if (_db.getFile().isEncrypted()) {
+        if (_db.isEncryptionEnabled()) {
             final String[] items = {"Keep the database encrypted"};
             final boolean[] checkedItems = {true};
             builder.setMultiChoiceItems(items, checkedItems, new DialogInterface.OnMultiChoiceClickListener() {
@@ -375,8 +365,8 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
             return;
         }
 
-        SlotList slots = (SlotList) data.getSerializableExtra("slots");
+        DatabaseFileCredentials creds = (DatabaseFileCredentials) data.getSerializableExtra("creds");
-        _db.getFile().setSlots(slots);
+        _db.setCredentials(creds);
         saveDatabase();
     }
 
@@ -384,7 +374,6 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
         try {
             _db.save();
         } catch (DatabaseManagerException e) {
-            e.printStackTrace();
             Toast.makeText(getActivity(), "An error occurred while trying to save the database", Toast.LENGTH_LONG).show();
             return false;
         }
@@ -394,19 +383,17 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
 
     @Override
     public void onSlotResult(Slot slot, Cipher cipher) {
-        MasterKey masterKey = MasterKey.generate();
+        DatabaseFileCredentials creds = new DatabaseFileCredentials();
 
-        SlotList slots = new SlotList();
         try {
-            slot.setKey(masterKey, cipher);
+            slot.setKey(creds.getKey(), cipher);
-        } catch (SlotException e) {
+            creds.getSlots().add(slot);
+            _db.enableEncryption(creds);
+        } catch (DatabaseManagerException | SlotException e) {
             onException(e);
             return;
         }
-        slots.add(slot);
-        _db.enableEncryption(masterKey, slots);
 
-        saveDatabase();
         updateEncryptionPreference();
     }
 
@@ -417,7 +404,7 @@ public class PreferencesFragment extends PreferenceFragmentCompat implements Pas
     }
 
     private void updateEncryptionPreference() {
-        boolean encrypted = _db.getFile().isEncrypted();
+        boolean encrypted = _db.isEncryptionEnabled();
         _encryptionPreference.setChecked(encrypted, true);
         _slotsPreference.setEnabled(encrypted);
     }

app/src/main/java/me/impy/aegis/ui/ScannerActivity.java

@@ -110,10 +110,7 @@ public class ScannerActivity extends AegisActivity implements ZXingScannerView.R
             // parse google auth uri
             Uri uri = Uri.parse(rawResult.getText());
             GoogleAuthInfo info = GoogleAuthInfo.parseUri(uri);
-
+            DatabaseEntry entry = new DatabaseEntry(info);
-            DatabaseEntry entry = new DatabaseEntry(info.getOtpInfo());
-            entry.setIssuer(info.getIssuer());
-            entry.setName(info.getAccountName());
 
             Intent intent = new Intent();
             intent.putExtra("entry", entry);

app/src/main/java/me/impy/aegis/ui/SlotManagerActivity.java

@@ -16,7 +16,7 @@ import javax.crypto.Cipher;
 import me.impy.aegis.R;
 import me.impy.aegis.crypto.KeyStoreHandle;
 import me.impy.aegis.crypto.KeyStoreHandleException;
-import me.impy.aegis.crypto.MasterKey;
+import me.impy.aegis.db.DatabaseFileCredentials;
 import me.impy.aegis.db.slots.FingerprintSlot;
 import me.impy.aegis.db.slots.PasswordSlot;
 import me.impy.aegis.db.slots.Slot;
@@ -29,8 +29,7 @@ import me.impy.aegis.ui.views.SlotAdapter;
 import me.impy.aegis.ui.dialogs.SlotDialogFragment;
 
 public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Listener, SlotDialogFragment.Listener {
-    private MasterKey _masterKey;
+    private DatabaseFileCredentials _creds;
-    private SlotList _slots;
     private SlotAdapter _adapter;
 
     private boolean _edited;
@@ -59,9 +58,8 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
         slotsView.setNestedScrollingEnabled(false);
 
         // load the slots and masterKey
-        _masterKey = (MasterKey) getIntent().getSerializableExtra("masterKey");
+        _creds = (DatabaseFileCredentials) getIntent().getSerializableExtra("creds");
-        _slots = (SlotList) getIntent().getSerializableExtra("slots");
+        for (Slot slot : _creds.getSlots()) {
-        for (Slot slot : _slots) {
             _adapter.addSlot(slot);
         }
 
@@ -75,7 +73,7 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
         if (FingerprintHelper.getManager(this) != null) {
             try {
                 KeyStoreHandle keyStore = new KeyStoreHandle();
-                for (FingerprintSlot slot : _slots.findAll(FingerprintSlot.class)) {
+                for (FingerprintSlot slot : _creds.getSlots().findAll(FingerprintSlot.class)) {
                     if (keyStore.containsKey(slot.getUUID().toString())) {
                         visibility = View.GONE;
                         break;
@@ -92,7 +90,7 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
 
     private void onSave() {
         Intent intent = new Intent();
-        intent.putExtra("slots", _slots);
+        intent.putExtra("creds", _creds);
         setResult(RESULT_OK, intent);
         finish();
     }
@@ -150,7 +148,8 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
 
     @Override
     public void onRemoveSlot(Slot slot) {
-        if (slot instanceof PasswordSlot && _slots.findAll(PasswordSlot.class).size() <= 1) {
+        SlotList slots = _creds.getSlots();
+        if (slot instanceof PasswordSlot && slots.findAll(PasswordSlot.class).size() <= 1) {
             Toast.makeText(this, "You must have at least one password slot", Toast.LENGTH_SHORT).show();
             return;
         }
@@ -159,7 +158,7 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
                 .setTitle("Remove slot")
                 .setMessage("Are you sure you want to remove this slot?")
                 .setPositiveButton(android.R.string.yes, (dialog, whichButton) -> {
-                    _slots.remove(slot);
+                    slots.remove(slot);
                     _adapter.removeSlot(slot);
                     _edited = true;
                     updateFingerprintButton();
@@ -171,13 +170,13 @@ public class SlotManagerActivity extends AegisActivity implements SlotAdapter.Li
     @Override
     public void onSlotResult(Slot slot, Cipher cipher) {
         try {
-            slot.setKey(_masterKey, cipher);
+            slot.setKey(_creds.getKey(), cipher);
         } catch (SlotException e) {
             onException(e);
             return;
         }
 
-        _slots.add(slot);
+        _creds.getSlots().add(slot);
         _adapter.addSlot(slot);
         _edited = true;
         updateFingerprintButton();