1package eu.siacs.conversations.persistance;
   2
   3import android.content.ContentValues;
   4import android.content.Context;
   5import android.database.Cursor;
   6import android.database.DatabaseUtils;
   7import android.database.sqlite.SQLiteCantOpenDatabaseException;
   8import android.database.sqlite.SQLiteDatabase;
   9import android.database.sqlite.SQLiteOpenHelper;
  10import android.util.Base64;
  11import android.util.Log;
  12import android.util.Pair;
  13
  14import org.json.JSONObject;
  15import org.whispersystems.libaxolotl.AxolotlAddress;
  16import org.whispersystems.libaxolotl.IdentityKey;
  17import org.whispersystems.libaxolotl.IdentityKeyPair;
  18import org.whispersystems.libaxolotl.InvalidKeyException;
  19import org.whispersystems.libaxolotl.state.PreKeyRecord;
  20import org.whispersystems.libaxolotl.state.SessionRecord;
  21import org.whispersystems.libaxolotl.state.SignedPreKeyRecord;
  22
  23import java.io.ByteArrayInputStream;
  24import java.io.IOException;
  25import java.security.cert.CertificateEncodingException;
  26import java.security.cert.CertificateException;
  27import java.security.cert.CertificateFactory;
  28import java.security.cert.X509Certificate;
  29import java.util.ArrayList;
  30import java.util.HashSet;
  31import java.util.Iterator;
  32import java.util.List;
  33import java.util.Set;
  34import java.util.concurrent.CopyOnWriteArrayList;
  35import org.json.JSONException;
  36
  37import eu.siacs.conversations.Config;
  38import eu.siacs.conversations.crypto.axolotl.AxolotlService;
  39import eu.siacs.conversations.crypto.axolotl.SQLiteAxolotlStore;
  40import eu.siacs.conversations.crypto.axolotl.XmppAxolotlSession;
  41import eu.siacs.conversations.entities.Account;
  42import eu.siacs.conversations.entities.Contact;
  43import eu.siacs.conversations.entities.Conversation;
  44import eu.siacs.conversations.entities.Message;
  45import eu.siacs.conversations.entities.PresenceTemplate;
  46import eu.siacs.conversations.entities.Roster;
  47import eu.siacs.conversations.entities.ServiceDiscoveryResult;
  48import eu.siacs.conversations.generator.AbstractGenerator;
  49import eu.siacs.conversations.xmpp.jid.InvalidJidException;
  50import eu.siacs.conversations.xmpp.jid.Jid;
  51
  52public class DatabaseBackend extends SQLiteOpenHelper {
  53
  54	private static DatabaseBackend instance = null;
  55
  56	private static final String DATABASE_NAME = "history";
  57	private static final int DATABASE_VERSION = 30;
  58
  59	private static String CREATE_CONTATCS_STATEMENT = "create table "
  60			+ Contact.TABLENAME + "(" + Contact.ACCOUNT + " TEXT, "
  61			+ Contact.SERVERNAME + " TEXT, " + Contact.SYSTEMNAME + " TEXT,"
  62			+ Contact.JID + " TEXT," + Contact.KEYS + " TEXT,"
  63			+ Contact.PHOTOURI + " TEXT," + Contact.OPTIONS + " NUMBER,"
  64			+ Contact.SYSTEMACCOUNT + " NUMBER, " + Contact.AVATAR + " TEXT, "
  65			+ Contact.LAST_PRESENCE + " TEXT, " + Contact.LAST_TIME + " NUMBER, "
  66			+ Contact.GROUPS + " TEXT, FOREIGN KEY(" + Contact.ACCOUNT + ") REFERENCES "
  67			+ Account.TABLENAME + "(" + Account.UUID
  68			+ ") ON DELETE CASCADE, UNIQUE(" + Contact.ACCOUNT + ", "
  69			+ Contact.JID + ") ON CONFLICT REPLACE);";
  70
  71	private static String CREATE_DISCOVERY_RESULTS_STATEMENT = "create table "
  72			+ ServiceDiscoveryResult.TABLENAME + "("
  73			+ ServiceDiscoveryResult.HASH + " TEXT, "
  74			+ ServiceDiscoveryResult.VER + " TEXT, "
  75			+ ServiceDiscoveryResult.RESULT + " TEXT, "
  76			+ "UNIQUE(" + ServiceDiscoveryResult.HASH + ", "
  77			+ ServiceDiscoveryResult.VER + ") ON CONFLICT REPLACE);";
  78
  79	private static String CREATE_PRESENCE_TEMPLATES_STATEMENT = "CREATE TABLE "
  80			+ PresenceTemplate.TABELNAME + "("
  81			+ PresenceTemplate.UUID + " TEXT, "
  82			+ PresenceTemplate.LAST_USED + " NUMBER,"
  83			+ PresenceTemplate.MESSAGE + " TEXT,"
  84			+ PresenceTemplate.STATUS + " TEXT,"
  85			+ "UNIQUE("+PresenceTemplate.MESSAGE + "," +PresenceTemplate.STATUS+") ON CONFLICT REPLACE);";
  86
  87	private static String CREATE_PREKEYS_STATEMENT = "CREATE TABLE "
  88			+ SQLiteAxolotlStore.PREKEY_TABLENAME + "("
  89			+ SQLiteAxolotlStore.ACCOUNT + " TEXT,  "
  90			+ SQLiteAxolotlStore.ID + " INTEGER, "
  91			+ SQLiteAxolotlStore.KEY + " TEXT, FOREIGN KEY("
  92			+ SQLiteAxolotlStore.ACCOUNT
  93			+ ") REFERENCES " + Account.TABLENAME + "(" + Account.UUID + ") ON DELETE CASCADE, "
  94			+ "UNIQUE( " + SQLiteAxolotlStore.ACCOUNT + ", "
  95			+ SQLiteAxolotlStore.ID
  96			+ ") ON CONFLICT REPLACE"
  97			+ ");";
  98
  99	private static String CREATE_SIGNED_PREKEYS_STATEMENT = "CREATE TABLE "
 100			+ SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME + "("
 101			+ SQLiteAxolotlStore.ACCOUNT + " TEXT,  "
 102			+ SQLiteAxolotlStore.ID + " INTEGER, "
 103			+ SQLiteAxolotlStore.KEY + " TEXT, FOREIGN KEY("
 104			+ SQLiteAxolotlStore.ACCOUNT
 105			+ ") REFERENCES " + Account.TABLENAME + "(" + Account.UUID + ") ON DELETE CASCADE, "
 106			+ "UNIQUE( " + SQLiteAxolotlStore.ACCOUNT + ", "
 107			+ SQLiteAxolotlStore.ID
 108			+ ") ON CONFLICT REPLACE" +
 109			");";
 110
 111	private static String CREATE_SESSIONS_STATEMENT = "CREATE TABLE "
 112			+ SQLiteAxolotlStore.SESSION_TABLENAME + "("
 113			+ SQLiteAxolotlStore.ACCOUNT + " TEXT,  "
 114			+ SQLiteAxolotlStore.NAME + " TEXT, "
 115			+ SQLiteAxolotlStore.DEVICE_ID + " INTEGER, "
 116			+ SQLiteAxolotlStore.KEY + " TEXT, FOREIGN KEY("
 117			+ SQLiteAxolotlStore.ACCOUNT
 118			+ ") REFERENCES " + Account.TABLENAME + "(" + Account.UUID + ") ON DELETE CASCADE, "
 119			+ "UNIQUE( " + SQLiteAxolotlStore.ACCOUNT + ", "
 120			+ SQLiteAxolotlStore.NAME + ", "
 121			+ SQLiteAxolotlStore.DEVICE_ID
 122			+ ") ON CONFLICT REPLACE"
 123			+ ");";
 124
 125	private static String CREATE_IDENTITIES_STATEMENT = "CREATE TABLE "
 126			+ SQLiteAxolotlStore.IDENTITIES_TABLENAME + "("
 127			+ SQLiteAxolotlStore.ACCOUNT + " TEXT,  "
 128			+ SQLiteAxolotlStore.NAME + " TEXT, "
 129			+ SQLiteAxolotlStore.OWN + " INTEGER, "
 130			+ SQLiteAxolotlStore.FINGERPRINT + " TEXT, "
 131			+ SQLiteAxolotlStore.CERTIFICATE + " BLOB, "
 132			+ SQLiteAxolotlStore.TRUSTED + " INTEGER, "
 133			+ SQLiteAxolotlStore.KEY + " TEXT, FOREIGN KEY("
 134			+ SQLiteAxolotlStore.ACCOUNT
 135			+ ") REFERENCES " + Account.TABLENAME + "(" + Account.UUID + ") ON DELETE CASCADE, "
 136			+ "UNIQUE( " + SQLiteAxolotlStore.ACCOUNT + ", "
 137			+ SQLiteAxolotlStore.NAME + ", "
 138			+ SQLiteAxolotlStore.FINGERPRINT
 139			+ ") ON CONFLICT IGNORE"
 140			+ ");";
 141
 142	private static String START_TIMES_TABLE = "start_times";
 143
 144	private static String CREATE_START_TIMES_TABLE = "create table "+START_TIMES_TABLE+" (timestamp NUMBER);";
 145
 146	private DatabaseBackend(Context context) {
 147		super(context, DATABASE_NAME, null, DATABASE_VERSION);
 148	}
 149
 150	@Override
 151	public void onCreate(SQLiteDatabase db) {
 152		db.execSQL("PRAGMA foreign_keys=ON;");
 153		db.execSQL("create table " + Account.TABLENAME + "(" + Account.UUID+ " TEXT PRIMARY KEY,"
 154				+ Account.USERNAME + " TEXT,"
 155				+ Account.SERVER + " TEXT,"
 156				+ Account.PASSWORD + " TEXT,"
 157				+ Account.DISPLAY_NAME + " TEXT, "
 158				+ Account.STATUS + " TEXT,"
 159				+ Account.STATUS_MESSAGE + " TEXT,"
 160				+ Account.ROSTERVERSION + " TEXT,"
 161				+ Account.OPTIONS + " NUMBER, "
 162				+ Account.AVATAR + " TEXT, "
 163				+ Account.KEYS + " TEXT, "
 164				+ Account.HOSTNAME + " TEXT, "
 165				+ Account.PORT + " NUMBER DEFAULT 5222)");
 166		db.execSQL("create table " + Conversation.TABLENAME + " ("
 167				+ Conversation.UUID + " TEXT PRIMARY KEY, " + Conversation.NAME
 168				+ " TEXT, " + Conversation.CONTACT + " TEXT, "
 169				+ Conversation.ACCOUNT + " TEXT, " + Conversation.CONTACTJID
 170				+ " TEXT, " + Conversation.CREATED + " NUMBER, "
 171				+ Conversation.STATUS + " NUMBER, " + Conversation.MODE
 172				+ " NUMBER, " + Conversation.ATTRIBUTES + " TEXT, FOREIGN KEY("
 173				+ Conversation.ACCOUNT + ") REFERENCES " + Account.TABLENAME
 174				+ "(" + Account.UUID + ") ON DELETE CASCADE);");
 175		db.execSQL("create table " + Message.TABLENAME + "( " + Message.UUID
 176				+ " TEXT PRIMARY KEY, " + Message.CONVERSATION + " TEXT, "
 177				+ Message.TIME_SENT + " NUMBER, " + Message.COUNTERPART
 178				+ " TEXT, " + Message.TRUE_COUNTERPART + " TEXT,"
 179				+ Message.BODY + " TEXT, " + Message.ENCRYPTION + " NUMBER, "
 180				+ Message.STATUS + " NUMBER," + Message.TYPE + " NUMBER, "
 181				+ Message.RELATIVE_FILE_PATH + " TEXT, "
 182				+ Message.SERVER_MSG_ID + " TEXT, "
 183				+ Message.FINGERPRINT + " TEXT, "
 184				+ Message.CARBON + " INTEGER, "
 185				+ Message.EDITED + " TEXT, "
 186				+ Message.READ + " NUMBER DEFAULT 1, "
 187				+ Message.OOB + " INTEGER, "
 188				+ Message.ERROR_MESSAGE + " TEXT,"
 189				+ Message.REMOTE_MSG_ID + " TEXT, FOREIGN KEY("
 190				+ Message.CONVERSATION + ") REFERENCES "
 191				+ Conversation.TABLENAME + "(" + Conversation.UUID
 192				+ ") ON DELETE CASCADE);");
 193
 194		db.execSQL(CREATE_CONTATCS_STATEMENT);
 195		db.execSQL(CREATE_DISCOVERY_RESULTS_STATEMENT);
 196		db.execSQL(CREATE_SESSIONS_STATEMENT);
 197		db.execSQL(CREATE_PREKEYS_STATEMENT);
 198		db.execSQL(CREATE_SIGNED_PREKEYS_STATEMENT);
 199		db.execSQL(CREATE_IDENTITIES_STATEMENT);
 200		db.execSQL(CREATE_PRESENCE_TEMPLATES_STATEMENT);
 201		db.execSQL(CREATE_START_TIMES_TABLE);
 202	}
 203
 204	@Override
 205	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
 206		if (oldVersion < 2 && newVersion >= 2) {
 207			db.execSQL("update " + Account.TABLENAME + " set "
 208					+ Account.OPTIONS + " = " + Account.OPTIONS + " | 8");
 209		}
 210		if (oldVersion < 3 && newVersion >= 3) {
 211			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 212					+ Message.TYPE + " NUMBER");
 213		}
 214		if (oldVersion < 5 && newVersion >= 5) {
 215			db.execSQL("DROP TABLE " + Contact.TABLENAME);
 216			db.execSQL(CREATE_CONTATCS_STATEMENT);
 217			db.execSQL("UPDATE " + Account.TABLENAME + " SET "
 218					+ Account.ROSTERVERSION + " = NULL");
 219		}
 220		if (oldVersion < 6 && newVersion >= 6) {
 221			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 222					+ Message.TRUE_COUNTERPART + " TEXT");
 223		}
 224		if (oldVersion < 7 && newVersion >= 7) {
 225			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 226					+ Message.REMOTE_MSG_ID + " TEXT");
 227			db.execSQL("ALTER TABLE " + Contact.TABLENAME + " ADD COLUMN "
 228					+ Contact.AVATAR + " TEXT");
 229			db.execSQL("ALTER TABLE " + Account.TABLENAME + " ADD COLUMN "
 230					+ Account.AVATAR + " TEXT");
 231		}
 232		if (oldVersion < 8 && newVersion >= 8) {
 233			db.execSQL("ALTER TABLE " + Conversation.TABLENAME + " ADD COLUMN "
 234					+ Conversation.ATTRIBUTES + " TEXT");
 235		}
 236		if (oldVersion < 9 && newVersion >= 9) {
 237			db.execSQL("ALTER TABLE " + Contact.TABLENAME + " ADD COLUMN "
 238					+ Contact.LAST_TIME + " NUMBER");
 239			db.execSQL("ALTER TABLE " + Contact.TABLENAME + " ADD COLUMN "
 240					+ Contact.LAST_PRESENCE + " TEXT");
 241		}
 242		if (oldVersion < 10 && newVersion >= 10) {
 243			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 244					+ Message.RELATIVE_FILE_PATH + " TEXT");
 245		}
 246		if (oldVersion < 11 && newVersion >= 11) {
 247			db.execSQL("ALTER TABLE " + Contact.TABLENAME + " ADD COLUMN "
 248					+ Contact.GROUPS + " TEXT");
 249			db.execSQL("delete from " + Contact.TABLENAME);
 250			db.execSQL("update " + Account.TABLENAME + " set " + Account.ROSTERVERSION + " = NULL");
 251		}
 252		if (oldVersion < 12 && newVersion >= 12) {
 253			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 254					+ Message.SERVER_MSG_ID + " TEXT");
 255		}
 256		if (oldVersion < 13 && newVersion >= 13) {
 257			db.execSQL("delete from " + Contact.TABLENAME);
 258			db.execSQL("update " + Account.TABLENAME + " set " + Account.ROSTERVERSION + " = NULL");
 259		}
 260		if (oldVersion < 14 && newVersion >= 14) {
 261			canonicalizeJids(db);
 262		}
 263		if (oldVersion < 15 && newVersion >= 15) {
 264			recreateAxolotlDb(db);
 265			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 266					+ Message.FINGERPRINT + " TEXT");
 267		} else if (oldVersion < 22 && newVersion >= 22) {
 268			db.execSQL("ALTER TABLE " + SQLiteAxolotlStore.IDENTITIES_TABLENAME + " ADD COLUMN " + SQLiteAxolotlStore.CERTIFICATE);
 269		}
 270		if (oldVersion < 16 && newVersion >= 16) {
 271			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN "
 272					+ Message.CARBON + " INTEGER");
 273		}
 274		if (oldVersion < 19 && newVersion >= 19) {
 275			db.execSQL("ALTER TABLE " + Account.TABLENAME + " ADD COLUMN " + Account.DISPLAY_NAME + " TEXT");
 276		}
 277		if (oldVersion < 20 && newVersion >= 20) {
 278			db.execSQL("ALTER TABLE " + Account.TABLENAME + " ADD COLUMN " + Account.HOSTNAME + " TEXT");
 279			db.execSQL("ALTER TABLE " + Account.TABLENAME + " ADD COLUMN " + Account.PORT + " NUMBER DEFAULT 5222");
 280		}
 281		if (oldVersion < 26 && newVersion >= 26) {
 282			db.execSQL("ALTER TABLE " + Account.TABLENAME + " ADD COLUMN " + Account.STATUS + " TEXT");
 283			db.execSQL("ALTER TABLE " + Account.TABLENAME + " ADD COLUMN " + Account.STATUS_MESSAGE + " TEXT");
 284		}
 285		/* Any migrations that alter the Account table need to happen BEFORE this migration, as it
 286		 * depends on account de-serialization.
 287		 */
 288		if (oldVersion < 17 && newVersion >= 17) {
 289			List<Account> accounts = getAccounts(db);
 290			for (Account account : accounts) {
 291				String ownDeviceIdString = account.getKey(SQLiteAxolotlStore.JSONKEY_REGISTRATION_ID);
 292				if (ownDeviceIdString == null) {
 293					continue;
 294				}
 295				int ownDeviceId = Integer.valueOf(ownDeviceIdString);
 296				AxolotlAddress ownAddress = new AxolotlAddress(account.getJid().toBareJid().toPreppedString(), ownDeviceId);
 297				deleteSession(db, account, ownAddress);
 298				IdentityKeyPair identityKeyPair = loadOwnIdentityKeyPair(db, account);
 299				if (identityKeyPair != null) {
 300					setIdentityKeyTrust(db, account, identityKeyPair.getPublicKey().getFingerprint().replaceAll("\\s", ""), XmppAxolotlSession.Trust.TRUSTED);
 301				} else {
 302					Log.d(Config.LOGTAG, account.getJid().toBareJid() + ": could not load own identity key pair");
 303				}
 304			}
 305		}
 306		if (oldVersion < 18 && newVersion >= 18) {
 307			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN " + Message.READ + " NUMBER DEFAULT 1");
 308		}
 309
 310		if (oldVersion < 21 && newVersion >= 21) {
 311			List<Account> accounts = getAccounts(db);
 312			for (Account account : accounts) {
 313				account.unsetPgpSignature();
 314				db.update(Account.TABLENAME, account.getContentValues(), Account.UUID
 315						+ "=?", new String[]{account.getUuid()});
 316			}
 317		}
 318
 319		if (oldVersion < 23 && newVersion >= 23) {
 320			db.execSQL(CREATE_DISCOVERY_RESULTS_STATEMENT);
 321		}
 322
 323		if (oldVersion < 24 && newVersion >= 24) {
 324			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN " + Message.EDITED + " TEXT");
 325		}
 326
 327		if (oldVersion < 25 && newVersion >= 25) {
 328			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN " + Message.OOB + " INTEGER");
 329		}
 330
 331		if (oldVersion <  26 && newVersion >= 26) {
 332			db.execSQL(CREATE_PRESENCE_TEMPLATES_STATEMENT);
 333		}
 334
 335		if (oldVersion < 27 && newVersion >= 27) {
 336			db.execSQL("DELETE FROM "+ServiceDiscoveryResult.TABLENAME);
 337		}
 338
 339		if (oldVersion < 28 && newVersion >= 28) {
 340			canonicalizeJids(db);
 341		}
 342
 343		if (oldVersion < 29 && newVersion >= 29) {
 344			db.execSQL("ALTER TABLE " + Message.TABLENAME + " ADD COLUMN " + Message.ERROR_MESSAGE + " TEXT");
 345		}
 346		if (oldVersion < 30 && newVersion >= 30) {
 347			db.execSQL(CREATE_START_TIMES_TABLE);
 348		}
 349	}
 350
 351	private void canonicalizeJids(SQLiteDatabase db) {
 352		// migrate db to new, canonicalized JID domainpart representation
 353
 354		// Conversation table
 355		Cursor cursor = db.rawQuery("select * from " + Conversation.TABLENAME, new String[0]);
 356		while (cursor.moveToNext()) {
 357			String newJid;
 358			try {
 359				newJid = Jid.fromString(
 360						cursor.getString(cursor.getColumnIndex(Conversation.CONTACTJID))
 361				).toPreppedString();
 362			} catch (InvalidJidException ignored) {
 363				Log.e(Config.LOGTAG, "Failed to migrate Conversation CONTACTJID "
 364						+ cursor.getString(cursor.getColumnIndex(Conversation.CONTACTJID))
 365						+ ": " + ignored + ". Skipping...");
 366				continue;
 367			}
 368
 369			String updateArgs[] = {
 370					newJid,
 371					cursor.getString(cursor.getColumnIndex(Conversation.UUID)),
 372			};
 373			db.execSQL("update " + Conversation.TABLENAME
 374					+ " set " + Conversation.CONTACTJID + " = ? "
 375					+ " where " + Conversation.UUID + " = ?", updateArgs);
 376		}
 377		cursor.close();
 378
 379		// Contact table
 380		cursor = db.rawQuery("select * from " + Contact.TABLENAME, new String[0]);
 381		while (cursor.moveToNext()) {
 382			String newJid;
 383			try {
 384				newJid = Jid.fromString(
 385						cursor.getString(cursor.getColumnIndex(Contact.JID))
 386				).toPreppedString();
 387			} catch (InvalidJidException ignored) {
 388				Log.e(Config.LOGTAG, "Failed to migrate Contact JID "
 389						+ cursor.getString(cursor.getColumnIndex(Contact.JID))
 390						+ ": " + ignored + ". Skipping...");
 391				continue;
 392			}
 393
 394			String updateArgs[] = {
 395					newJid,
 396					cursor.getString(cursor.getColumnIndex(Contact.ACCOUNT)),
 397					cursor.getString(cursor.getColumnIndex(Contact.JID)),
 398			};
 399			db.execSQL("update " + Contact.TABLENAME
 400					+ " set " + Contact.JID + " = ? "
 401					+ " where " + Contact.ACCOUNT + " = ? "
 402					+ " AND " + Contact.JID + " = ?", updateArgs);
 403		}
 404		cursor.close();
 405
 406		// Account table
 407		cursor = db.rawQuery("select * from " + Account.TABLENAME, new String[0]);
 408		while (cursor.moveToNext()) {
 409			String newServer;
 410			try {
 411				newServer = Jid.fromParts(
 412						cursor.getString(cursor.getColumnIndex(Account.USERNAME)),
 413						cursor.getString(cursor.getColumnIndex(Account.SERVER)),
 414						"mobile"
 415				).getDomainpart();
 416			} catch (InvalidJidException ignored) {
 417				Log.e(Config.LOGTAG, "Failed to migrate Account SERVER "
 418						+ cursor.getString(cursor.getColumnIndex(Account.SERVER))
 419						+ ": " + ignored + ". Skipping...");
 420				continue;
 421			}
 422
 423			String updateArgs[] = {
 424					newServer,
 425					cursor.getString(cursor.getColumnIndex(Account.UUID)),
 426			};
 427			db.execSQL("update " + Account.TABLENAME
 428					+ " set " + Account.SERVER + " = ? "
 429					+ " where " + Account.UUID + " = ?", updateArgs);
 430		}
 431		cursor.close();
 432	}
 433
 434	public static synchronized DatabaseBackend getInstance(Context context) {
 435		if (instance == null) {
 436			instance = new DatabaseBackend(context);
 437		}
 438		return instance;
 439	}
 440
 441	public void createConversation(Conversation conversation) {
 442		SQLiteDatabase db = this.getWritableDatabase();
 443		db.insert(Conversation.TABLENAME, null, conversation.getContentValues());
 444	}
 445
 446	public void createMessage(Message message) {
 447		SQLiteDatabase db = this.getWritableDatabase();
 448		db.insert(Message.TABLENAME, null, message.getContentValues());
 449	}
 450
 451	public void createAccount(Account account) {
 452		SQLiteDatabase db = this.getWritableDatabase();
 453		db.insert(Account.TABLENAME, null, account.getContentValues());
 454	}
 455
 456	public void insertDiscoveryResult(ServiceDiscoveryResult result) {
 457		SQLiteDatabase db = this.getWritableDatabase();
 458		db.insert(ServiceDiscoveryResult.TABLENAME, null, result.getContentValues());
 459	}
 460
 461	public ServiceDiscoveryResult findDiscoveryResult(final String hash, final String ver) {
 462		SQLiteDatabase db = this.getReadableDatabase();
 463		String[] selectionArgs = {hash, ver};
 464		Cursor cursor = db.query(ServiceDiscoveryResult.TABLENAME, null,
 465				ServiceDiscoveryResult.HASH + "=? AND " + ServiceDiscoveryResult.VER + "=?",
 466				selectionArgs, null, null, null);
 467		if (cursor.getCount() == 0) {
 468			cursor.close();
 469			return null;
 470		}
 471		cursor.moveToFirst();
 472
 473		ServiceDiscoveryResult result = null;
 474		try {
 475			result = new ServiceDiscoveryResult(cursor);
 476		} catch (JSONException e) { /* result is still null */ }
 477
 478		cursor.close();
 479		return result;
 480	}
 481
 482	public void insertPresenceTemplate(PresenceTemplate template) {
 483		SQLiteDatabase db = this.getWritableDatabase();
 484		db.insert(PresenceTemplate.TABELNAME, null, template.getContentValues());
 485	}
 486
 487	public List<PresenceTemplate> getPresenceTemplates() {
 488		ArrayList<PresenceTemplate> templates = new ArrayList<>();
 489		SQLiteDatabase db = this.getReadableDatabase();
 490		Cursor cursor = db.query(PresenceTemplate.TABELNAME,null,null,null,null,null,PresenceTemplate.LAST_USED+" desc");
 491		while (cursor.moveToNext()) {
 492			templates.add(PresenceTemplate.fromCursor(cursor));
 493		}
 494		cursor.close();
 495		return templates;
 496	}
 497
 498	public void deletePresenceTemplate(PresenceTemplate template) {
 499		Log.d(Config.LOGTAG,"deleting presence template with uuid "+template.getUuid());
 500		SQLiteDatabase db = this.getWritableDatabase();
 501		String where = PresenceTemplate.UUID+"=?";
 502		String[] whereArgs = {template.getUuid()};
 503		db.delete(PresenceTemplate.TABELNAME,where,whereArgs);
 504	}
 505
 506	public CopyOnWriteArrayList<Conversation> getConversations(int status) {
 507		CopyOnWriteArrayList<Conversation> list = new CopyOnWriteArrayList<>();
 508		SQLiteDatabase db = this.getReadableDatabase();
 509		String[] selectionArgs = {Integer.toString(status)};
 510		Cursor cursor = db.rawQuery("select * from " + Conversation.TABLENAME
 511				+ " where " + Conversation.STATUS + " = ? order by "
 512				+ Conversation.CREATED + " desc", selectionArgs);
 513		while (cursor.moveToNext()) {
 514			list.add(Conversation.fromCursor(cursor));
 515		}
 516		cursor.close();
 517		return list;
 518	}
 519
 520	public ArrayList<Message> getMessages(Conversation conversations, int limit) {
 521		return getMessages(conversations, limit, -1);
 522	}
 523
 524	public ArrayList<Message> getMessages(Conversation conversation, int limit,
 525										  long timestamp) {
 526		ArrayList<Message> list = new ArrayList<>();
 527		SQLiteDatabase db = this.getReadableDatabase();
 528		Cursor cursor;
 529		if (timestamp == -1) {
 530			String[] selectionArgs = {conversation.getUuid()};
 531			cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
 532					+ "=?", selectionArgs, null, null, Message.TIME_SENT
 533					+ " DESC", String.valueOf(limit));
 534		} else {
 535			String[] selectionArgs = {conversation.getUuid(),
 536					Long.toString(timestamp)};
 537			cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
 538							+ "=? and " + Message.TIME_SENT + "<?", selectionArgs,
 539					null, null, Message.TIME_SENT + " DESC",
 540					String.valueOf(limit));
 541		}
 542		if (cursor.getCount() > 0) {
 543			cursor.moveToLast();
 544			do {
 545				Message message = Message.fromCursor(cursor);
 546				message.setConversation(conversation);
 547				list.add(message);
 548			} while (cursor.moveToPrevious());
 549		}
 550		cursor.close();
 551		return list;
 552	}
 553
 554	public Iterable<Message> getMessagesIterable(final Conversation conversation) {
 555		return new Iterable<Message>() {
 556			@Override
 557			public Iterator<Message> iterator() {
 558				class MessageIterator implements Iterator<Message> {
 559					SQLiteDatabase db = getReadableDatabase();
 560					String[] selectionArgs = {conversation.getUuid()};
 561					Cursor cursor = db.query(Message.TABLENAME, null, Message.CONVERSATION
 562							+ "=?", selectionArgs, null, null, Message.TIME_SENT
 563							+ " ASC", null);
 564
 565					public MessageIterator() {
 566						cursor.moveToFirst();
 567					}
 568
 569					@Override
 570					public boolean hasNext() {
 571						return !cursor.isAfterLast();
 572					}
 573
 574					@Override
 575					public Message next() {
 576						Message message = Message.fromCursor(cursor);
 577						cursor.moveToNext();
 578						return message;
 579					}
 580
 581					@Override
 582					public void remove() {
 583						throw new UnsupportedOperationException();
 584					}
 585				}
 586				return new MessageIterator();
 587			}
 588		};
 589	}
 590
 591	public Conversation findConversation(final Account account, final Jid contactJid) {
 592		SQLiteDatabase db = this.getReadableDatabase();
 593		String[] selectionArgs = {account.getUuid(),
 594				contactJid.toBareJid().toPreppedString() + "/%",
 595				contactJid.toBareJid().toPreppedString()
 596		};
 597		Cursor cursor = db.query(Conversation.TABLENAME, null,
 598				Conversation.ACCOUNT + "=? AND (" + Conversation.CONTACTJID
 599						+ " like ? OR " + Conversation.CONTACTJID + "=?)", selectionArgs, null, null, null);
 600		if (cursor.getCount() == 0) {
 601			cursor.close();
 602			return null;
 603		}
 604		cursor.moveToFirst();
 605		Conversation conversation = Conversation.fromCursor(cursor);
 606		cursor.close();
 607		return conversation;
 608	}
 609
 610	public void updateConversation(final Conversation conversation) {
 611		final SQLiteDatabase db = this.getWritableDatabase();
 612		final String[] args = {conversation.getUuid()};
 613		db.update(Conversation.TABLENAME, conversation.getContentValues(),
 614				Conversation.UUID + "=?", args);
 615	}
 616
 617	public List<Account> getAccounts() {
 618		SQLiteDatabase db = this.getReadableDatabase();
 619		return getAccounts(db);
 620	}
 621
 622	private List<Account> getAccounts(SQLiteDatabase db) {
 623		List<Account> list = new ArrayList<>();
 624		Cursor cursor = db.query(Account.TABLENAME, null, null, null, null,
 625				null, null);
 626		while (cursor.moveToNext()) {
 627			list.add(Account.fromCursor(cursor));
 628		}
 629		cursor.close();
 630		return list;
 631	}
 632
 633	public boolean updateAccount(Account account) {
 634		SQLiteDatabase db = this.getWritableDatabase();
 635		String[] args = {account.getUuid()};
 636		final int rows = db.update(Account.TABLENAME, account.getContentValues(), Account.UUID + "=?", args);
 637		return rows == 1;
 638	}
 639
 640	public boolean deleteAccount(Account account) {
 641		SQLiteDatabase db = this.getWritableDatabase();
 642		String[] args = {account.getUuid()};
 643		final int rows = db.delete(Account.TABLENAME, Account.UUID + "=?", args);
 644		return rows == 1;
 645	}
 646
 647	public boolean hasEnabledAccounts() {
 648		SQLiteDatabase db = this.getReadableDatabase();
 649		Cursor cursor = db.rawQuery("select count(" + Account.UUID + ")  from "
 650				+ Account.TABLENAME + " where not options & (1 <<1)", null);
 651		try {
 652			cursor.moveToFirst();
 653			int count = cursor.getInt(0);
 654			return (count > 0);
 655		} catch (SQLiteCantOpenDatabaseException e) {
 656			return true; // better safe than sorry
 657		} catch (RuntimeException e) {
 658			return true; // better safe than sorry
 659		} finally {
 660			if (cursor != null) {
 661				cursor.close();
 662			}
 663		}
 664	}
 665
 666	@Override
 667	public SQLiteDatabase getWritableDatabase() {
 668		SQLiteDatabase db = super.getWritableDatabase();
 669		db.execSQL("PRAGMA foreign_keys=ON;");
 670		return db;
 671	}
 672
 673	public void updateMessage(Message message) {
 674		SQLiteDatabase db = this.getWritableDatabase();
 675		String[] args = {message.getUuid()};
 676		db.update(Message.TABLENAME, message.getContentValues(), Message.UUID
 677				+ "=?", args);
 678	}
 679
 680	public void updateMessage(Message message, String uuid) {
 681		SQLiteDatabase db = this.getWritableDatabase();
 682		String[] args = {uuid};
 683		db.update(Message.TABLENAME, message.getContentValues(), Message.UUID
 684				+ "=?", args);
 685	}
 686
 687	public void readRoster(Roster roster) {
 688		SQLiteDatabase db = this.getReadableDatabase();
 689		Cursor cursor;
 690		String args[] = {roster.getAccount().getUuid()};
 691		cursor = db.query(Contact.TABLENAME, null, Contact.ACCOUNT + "=?", args, null, null, null);
 692		while (cursor.moveToNext()) {
 693			roster.initContact(Contact.fromCursor(cursor));
 694		}
 695		cursor.close();
 696	}
 697
 698	public void writeRoster(final Roster roster) {
 699		final Account account = roster.getAccount();
 700		final SQLiteDatabase db = this.getWritableDatabase();
 701		db.beginTransaction();
 702		for (Contact contact : roster.getContacts()) {
 703			if (contact.getOption(Contact.Options.IN_ROSTER)) {
 704				db.insert(Contact.TABLENAME, null, contact.getContentValues());
 705			} else {
 706				String where = Contact.ACCOUNT + "=? AND " + Contact.JID + "=?";
 707				String[] whereArgs = {account.getUuid(), contact.getJid().toPreppedString()};
 708				db.delete(Contact.TABLENAME, where, whereArgs);
 709			}
 710		}
 711		db.setTransactionSuccessful();
 712		db.endTransaction();
 713		account.setRosterVersion(roster.getVersion());
 714		updateAccount(account);
 715	}
 716
 717	public void deleteMessagesInConversation(Conversation conversation) {
 718		SQLiteDatabase db = this.getWritableDatabase();
 719		String[] args = {conversation.getUuid()};
 720		db.delete(Message.TABLENAME, Message.CONVERSATION + "=?", args);
 721	}
 722
 723	public Pair<Long, String> getLastMessageReceived(Account account) {
 724		Cursor cursor = null;
 725		try {
 726			SQLiteDatabase db = this.getReadableDatabase();
 727			String sql = "select messages.timeSent,messages.serverMsgId from accounts join conversations on accounts.uuid=conversations.accountUuid join messages on conversations.uuid=messages.conversationUuid where accounts.uuid=? and (messages.status=0 or messages.carbon=1 or messages.serverMsgId not null) order by messages.timesent desc limit 1";
 728			String[] args = {account.getUuid()};
 729			cursor = db.rawQuery(sql, args);
 730			if (cursor.getCount() == 0) {
 731				return null;
 732			} else {
 733				cursor.moveToFirst();
 734				return new Pair<>(cursor.getLong(0), cursor.getString(1));
 735			}
 736		} catch (Exception e) {
 737			return null;
 738		} finally {
 739			if (cursor != null) {
 740				cursor.close();
 741			}
 742		}
 743	}
 744
 745	public Pair<Long,String> getLastClearDate(Account account) {
 746		SQLiteDatabase db = this.getReadableDatabase();
 747		String[] columns = {Conversation.ATTRIBUTES};
 748		String selection = Conversation.ACCOUNT + "=?";
 749		String[] args = {account.getUuid()};
 750		Cursor cursor = db.query(Conversation.TABLENAME,columns,selection,args,null,null,null);
 751		long maxClearDate = 0;
 752		while (cursor.moveToNext()) {
 753			try {
 754				final JSONObject jsonObject = new JSONObject(cursor.getString(0));
 755				maxClearDate = Math.max(maxClearDate, jsonObject.getLong(Conversation.ATTRIBUTE_LAST_CLEAR_HISTORY));
 756			} catch (Exception e) {
 757				//ignored
 758			}
 759		}
 760		cursor.close();
 761		return new Pair<>(maxClearDate,null);
 762	}
 763
 764	private Cursor getCursorForSession(Account account, AxolotlAddress contact) {
 765		final SQLiteDatabase db = this.getReadableDatabase();
 766		String[] selectionArgs = {account.getUuid(),
 767				contact.getName(),
 768				Integer.toString(contact.getDeviceId())};
 769		return db.query(SQLiteAxolotlStore.SESSION_TABLENAME,
 770				null,
 771				SQLiteAxolotlStore.ACCOUNT + " = ? AND "
 772						+ SQLiteAxolotlStore.NAME + " = ? AND "
 773						+ SQLiteAxolotlStore.DEVICE_ID + " = ? ",
 774				selectionArgs,
 775				null, null, null);
 776	}
 777
 778	public SessionRecord loadSession(Account account, AxolotlAddress contact) {
 779		SessionRecord session = null;
 780		Cursor cursor = getCursorForSession(account, contact);
 781		if (cursor.getCount() != 0) {
 782			cursor.moveToFirst();
 783			try {
 784				session = new SessionRecord(Base64.decode(cursor.getString(cursor.getColumnIndex(SQLiteAxolotlStore.KEY)), Base64.DEFAULT));
 785			} catch (IOException e) {
 786				cursor.close();
 787				throw new AssertionError(e);
 788			}
 789		}
 790		cursor.close();
 791		return session;
 792	}
 793
 794	public List<Integer> getSubDeviceSessions(Account account, AxolotlAddress contact) {
 795		final SQLiteDatabase db = this.getReadableDatabase();
 796		return getSubDeviceSessions(db, account, contact);
 797	}
 798
 799	private List<Integer> getSubDeviceSessions(SQLiteDatabase db, Account account, AxolotlAddress contact) {
 800		List<Integer> devices = new ArrayList<>();
 801		String[] columns = {SQLiteAxolotlStore.DEVICE_ID};
 802		String[] selectionArgs = {account.getUuid(),
 803				contact.getName()};
 804		Cursor cursor = db.query(SQLiteAxolotlStore.SESSION_TABLENAME,
 805				columns,
 806				SQLiteAxolotlStore.ACCOUNT + " = ? AND "
 807						+ SQLiteAxolotlStore.NAME + " = ?",
 808				selectionArgs,
 809				null, null, null);
 810
 811		while (cursor.moveToNext()) {
 812			devices.add(cursor.getInt(
 813					cursor.getColumnIndex(SQLiteAxolotlStore.DEVICE_ID)));
 814		}
 815
 816		cursor.close();
 817		return devices;
 818	}
 819
 820	public boolean containsSession(Account account, AxolotlAddress contact) {
 821		Cursor cursor = getCursorForSession(account, contact);
 822		int count = cursor.getCount();
 823		cursor.close();
 824		return count != 0;
 825	}
 826
 827	public void storeSession(Account account, AxolotlAddress contact, SessionRecord session) {
 828		SQLiteDatabase db = this.getWritableDatabase();
 829		ContentValues values = new ContentValues();
 830		values.put(SQLiteAxolotlStore.NAME, contact.getName());
 831		values.put(SQLiteAxolotlStore.DEVICE_ID, contact.getDeviceId());
 832		values.put(SQLiteAxolotlStore.KEY, Base64.encodeToString(session.serialize(), Base64.DEFAULT));
 833		values.put(SQLiteAxolotlStore.ACCOUNT, account.getUuid());
 834		db.insert(SQLiteAxolotlStore.SESSION_TABLENAME, null, values);
 835	}
 836
 837	public void deleteSession(Account account, AxolotlAddress contact) {
 838		SQLiteDatabase db = this.getWritableDatabase();
 839		deleteSession(db, account, contact);
 840	}
 841
 842	private void deleteSession(SQLiteDatabase db, Account account, AxolotlAddress contact) {
 843		String[] args = {account.getUuid(),
 844				contact.getName(),
 845				Integer.toString(contact.getDeviceId())};
 846		db.delete(SQLiteAxolotlStore.SESSION_TABLENAME,
 847				SQLiteAxolotlStore.ACCOUNT + " = ? AND "
 848						+ SQLiteAxolotlStore.NAME + " = ? AND "
 849						+ SQLiteAxolotlStore.DEVICE_ID + " = ? ",
 850				args);
 851	}
 852
 853	public void deleteAllSessions(Account account, AxolotlAddress contact) {
 854		SQLiteDatabase db = this.getWritableDatabase();
 855		String[] args = {account.getUuid(), contact.getName()};
 856		db.delete(SQLiteAxolotlStore.SESSION_TABLENAME,
 857				SQLiteAxolotlStore.ACCOUNT + "=? AND "
 858						+ SQLiteAxolotlStore.NAME + " = ?",
 859				args);
 860	}
 861
 862	private Cursor getCursorForPreKey(Account account, int preKeyId) {
 863		SQLiteDatabase db = this.getReadableDatabase();
 864		String[] columns = {SQLiteAxolotlStore.KEY};
 865		String[] selectionArgs = {account.getUuid(), Integer.toString(preKeyId)};
 866		Cursor cursor = db.query(SQLiteAxolotlStore.PREKEY_TABLENAME,
 867				columns,
 868				SQLiteAxolotlStore.ACCOUNT + "=? AND "
 869						+ SQLiteAxolotlStore.ID + "=?",
 870				selectionArgs,
 871				null, null, null);
 872
 873		return cursor;
 874	}
 875
 876	public PreKeyRecord loadPreKey(Account account, int preKeyId) {
 877		PreKeyRecord record = null;
 878		Cursor cursor = getCursorForPreKey(account, preKeyId);
 879		if (cursor.getCount() != 0) {
 880			cursor.moveToFirst();
 881			try {
 882				record = new PreKeyRecord(Base64.decode(cursor.getString(cursor.getColumnIndex(SQLiteAxolotlStore.KEY)), Base64.DEFAULT));
 883			} catch (IOException e) {
 884				throw new AssertionError(e);
 885			}
 886		}
 887		cursor.close();
 888		return record;
 889	}
 890
 891	public boolean containsPreKey(Account account, int preKeyId) {
 892		Cursor cursor = getCursorForPreKey(account, preKeyId);
 893		int count = cursor.getCount();
 894		cursor.close();
 895		return count != 0;
 896	}
 897
 898	public void storePreKey(Account account, PreKeyRecord record) {
 899		SQLiteDatabase db = this.getWritableDatabase();
 900		ContentValues values = new ContentValues();
 901		values.put(SQLiteAxolotlStore.ID, record.getId());
 902		values.put(SQLiteAxolotlStore.KEY, Base64.encodeToString(record.serialize(), Base64.DEFAULT));
 903		values.put(SQLiteAxolotlStore.ACCOUNT, account.getUuid());
 904		db.insert(SQLiteAxolotlStore.PREKEY_TABLENAME, null, values);
 905	}
 906
 907	public void deletePreKey(Account account, int preKeyId) {
 908		SQLiteDatabase db = this.getWritableDatabase();
 909		String[] args = {account.getUuid(), Integer.toString(preKeyId)};
 910		db.delete(SQLiteAxolotlStore.PREKEY_TABLENAME,
 911				SQLiteAxolotlStore.ACCOUNT + "=? AND "
 912						+ SQLiteAxolotlStore.ID + "=?",
 913				args);
 914	}
 915
 916	private Cursor getCursorForSignedPreKey(Account account, int signedPreKeyId) {
 917		SQLiteDatabase db = this.getReadableDatabase();
 918		String[] columns = {SQLiteAxolotlStore.KEY};
 919		String[] selectionArgs = {account.getUuid(), Integer.toString(signedPreKeyId)};
 920		Cursor cursor = db.query(SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME,
 921				columns,
 922				SQLiteAxolotlStore.ACCOUNT + "=? AND " + SQLiteAxolotlStore.ID + "=?",
 923				selectionArgs,
 924				null, null, null);
 925
 926		return cursor;
 927	}
 928
 929	public SignedPreKeyRecord loadSignedPreKey(Account account, int signedPreKeyId) {
 930		SignedPreKeyRecord record = null;
 931		Cursor cursor = getCursorForSignedPreKey(account, signedPreKeyId);
 932		if (cursor.getCount() != 0) {
 933			cursor.moveToFirst();
 934			try {
 935				record = new SignedPreKeyRecord(Base64.decode(cursor.getString(cursor.getColumnIndex(SQLiteAxolotlStore.KEY)), Base64.DEFAULT));
 936			} catch (IOException e) {
 937				throw new AssertionError(e);
 938			}
 939		}
 940		cursor.close();
 941		return record;
 942	}
 943
 944	public List<SignedPreKeyRecord> loadSignedPreKeys(Account account) {
 945		List<SignedPreKeyRecord> prekeys = new ArrayList<>();
 946		SQLiteDatabase db = this.getReadableDatabase();
 947		String[] columns = {SQLiteAxolotlStore.KEY};
 948		String[] selectionArgs = {account.getUuid()};
 949		Cursor cursor = db.query(SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME,
 950				columns,
 951				SQLiteAxolotlStore.ACCOUNT + "=?",
 952				selectionArgs,
 953				null, null, null);
 954
 955		while (cursor.moveToNext()) {
 956			try {
 957				prekeys.add(new SignedPreKeyRecord(Base64.decode(cursor.getString(cursor.getColumnIndex(SQLiteAxolotlStore.KEY)), Base64.DEFAULT)));
 958			} catch (IOException ignored) {
 959			}
 960		}
 961		cursor.close();
 962		return prekeys;
 963	}
 964
 965	public boolean containsSignedPreKey(Account account, int signedPreKeyId) {
 966		Cursor cursor = getCursorForPreKey(account, signedPreKeyId);
 967		int count = cursor.getCount();
 968		cursor.close();
 969		return count != 0;
 970	}
 971
 972	public void storeSignedPreKey(Account account, SignedPreKeyRecord record) {
 973		SQLiteDatabase db = this.getWritableDatabase();
 974		ContentValues values = new ContentValues();
 975		values.put(SQLiteAxolotlStore.ID, record.getId());
 976		values.put(SQLiteAxolotlStore.KEY, Base64.encodeToString(record.serialize(), Base64.DEFAULT));
 977		values.put(SQLiteAxolotlStore.ACCOUNT, account.getUuid());
 978		db.insert(SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME, null, values);
 979	}
 980
 981	public void deleteSignedPreKey(Account account, int signedPreKeyId) {
 982		SQLiteDatabase db = this.getWritableDatabase();
 983		String[] args = {account.getUuid(), Integer.toString(signedPreKeyId)};
 984		db.delete(SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME,
 985				SQLiteAxolotlStore.ACCOUNT + "=? AND "
 986						+ SQLiteAxolotlStore.ID + "=?",
 987				args);
 988	}
 989
 990	private Cursor getIdentityKeyCursor(Account account, String name, boolean own) {
 991		final SQLiteDatabase db = this.getReadableDatabase();
 992		return getIdentityKeyCursor(db, account, name, own);
 993	}
 994
 995	private Cursor getIdentityKeyCursor(SQLiteDatabase db, Account account, String name, boolean own) {
 996		return getIdentityKeyCursor(db, account, name, own, null);
 997	}
 998
 999	private Cursor getIdentityKeyCursor(Account account, String fingerprint) {
1000		final SQLiteDatabase db = this.getReadableDatabase();
1001		return getIdentityKeyCursor(db, account, fingerprint);
1002	}
1003
1004	private Cursor getIdentityKeyCursor(SQLiteDatabase db, Account account, String fingerprint) {
1005		return getIdentityKeyCursor(db, account, null, null, fingerprint);
1006	}
1007
1008	private Cursor getIdentityKeyCursor(SQLiteDatabase db, Account account, String name, Boolean own, String fingerprint) {
1009		String[] columns = {SQLiteAxolotlStore.TRUSTED,
1010				SQLiteAxolotlStore.KEY};
1011		ArrayList<String> selectionArgs = new ArrayList<>(4);
1012		selectionArgs.add(account.getUuid());
1013		String selectionString = SQLiteAxolotlStore.ACCOUNT + " = ?";
1014		if (name != null) {
1015			selectionArgs.add(name);
1016			selectionString += " AND " + SQLiteAxolotlStore.NAME + " = ?";
1017		}
1018		if (fingerprint != null) {
1019			selectionArgs.add(fingerprint);
1020			selectionString += " AND " + SQLiteAxolotlStore.FINGERPRINT + " = ?";
1021		}
1022		if (own != null) {
1023			selectionArgs.add(own ? "1" : "0");
1024			selectionString += " AND " + SQLiteAxolotlStore.OWN + " = ?";
1025		}
1026		Cursor cursor = db.query(SQLiteAxolotlStore.IDENTITIES_TABLENAME,
1027				columns,
1028				selectionString,
1029				selectionArgs.toArray(new String[selectionArgs.size()]),
1030				null, null, null);
1031
1032		return cursor;
1033	}
1034
1035	public IdentityKeyPair loadOwnIdentityKeyPair(Account account) {
1036		SQLiteDatabase db = getReadableDatabase();
1037		return loadOwnIdentityKeyPair(db, account);
1038	}
1039
1040	private IdentityKeyPair loadOwnIdentityKeyPair(SQLiteDatabase db, Account account) {
1041		String name = account.getJid().toBareJid().toPreppedString();
1042		IdentityKeyPair identityKeyPair = null;
1043		Cursor cursor = getIdentityKeyCursor(db, account, name, true);
1044		if (cursor.getCount() != 0) {
1045			cursor.moveToFirst();
1046			try {
1047				identityKeyPair = new IdentityKeyPair(Base64.decode(cursor.getString(cursor.getColumnIndex(SQLiteAxolotlStore.KEY)), Base64.DEFAULT));
1048			} catch (InvalidKeyException e) {
1049				Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Encountered invalid IdentityKey in database for account" + account.getJid().toBareJid() + ", address: " + name);
1050			}
1051		}
1052		cursor.close();
1053
1054		return identityKeyPair;
1055	}
1056
1057	public Set<IdentityKey> loadIdentityKeys(Account account, String name) {
1058		return loadIdentityKeys(account, name, null);
1059	}
1060
1061	public Set<IdentityKey> loadIdentityKeys(Account account, String name, XmppAxolotlSession.Trust trust) {
1062		Set<IdentityKey> identityKeys = new HashSet<>();
1063		Cursor cursor = getIdentityKeyCursor(account, name, false);
1064
1065		while (cursor.moveToNext()) {
1066			if (trust != null &&
1067					cursor.getInt(cursor.getColumnIndex(SQLiteAxolotlStore.TRUSTED))
1068							!= trust.getCode()) {
1069				continue;
1070			}
1071			try {
1072				identityKeys.add(new IdentityKey(Base64.decode(cursor.getString(cursor.getColumnIndex(SQLiteAxolotlStore.KEY)), Base64.DEFAULT), 0));
1073			} catch (InvalidKeyException e) {
1074				Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + "Encountered invalid IdentityKey in database for account" + account.getJid().toBareJid() + ", address: " + name);
1075			}
1076		}
1077		cursor.close();
1078
1079		return identityKeys;
1080	}
1081
1082	public long numTrustedKeys(Account account, String name) {
1083		SQLiteDatabase db = getReadableDatabase();
1084		String[] args = {
1085				account.getUuid(),
1086				name,
1087				String.valueOf(XmppAxolotlSession.Trust.TRUSTED.getCode()),
1088				String.valueOf(XmppAxolotlSession.Trust.TRUSTED_X509.getCode())
1089		};
1090		return DatabaseUtils.queryNumEntries(db, SQLiteAxolotlStore.IDENTITIES_TABLENAME,
1091				SQLiteAxolotlStore.ACCOUNT + " = ?"
1092						+ " AND " + SQLiteAxolotlStore.NAME + " = ?"
1093						+ " AND (" + SQLiteAxolotlStore.TRUSTED + " = ? OR " + SQLiteAxolotlStore.TRUSTED + " = ?)",
1094				args
1095		);
1096	}
1097
1098	private void storeIdentityKey(Account account, String name, boolean own, String fingerprint, String base64Serialized) {
1099		storeIdentityKey(account, name, own, fingerprint, base64Serialized, XmppAxolotlSession.Trust.UNDECIDED);
1100	}
1101
1102	private void storeIdentityKey(Account account, String name, boolean own, String fingerprint, String base64Serialized, XmppAxolotlSession.Trust trusted) {
1103		SQLiteDatabase db = this.getWritableDatabase();
1104		ContentValues values = new ContentValues();
1105		values.put(SQLiteAxolotlStore.ACCOUNT, account.getUuid());
1106		values.put(SQLiteAxolotlStore.NAME, name);
1107		values.put(SQLiteAxolotlStore.OWN, own ? 1 : 0);
1108		values.put(SQLiteAxolotlStore.FINGERPRINT, fingerprint);
1109		values.put(SQLiteAxolotlStore.KEY, base64Serialized);
1110		values.put(SQLiteAxolotlStore.TRUSTED, trusted.getCode());
1111		db.insert(SQLiteAxolotlStore.IDENTITIES_TABLENAME, null, values);
1112	}
1113
1114	public XmppAxolotlSession.Trust isIdentityKeyTrusted(Account account, String fingerprint) {
1115		Cursor cursor = getIdentityKeyCursor(account, fingerprint);
1116		XmppAxolotlSession.Trust trust = null;
1117		if (cursor.getCount() > 0) {
1118			cursor.moveToFirst();
1119			int trustValue = cursor.getInt(cursor.getColumnIndex(SQLiteAxolotlStore.TRUSTED));
1120			trust = XmppAxolotlSession.Trust.fromCode(trustValue);
1121		}
1122		cursor.close();
1123		return trust;
1124	}
1125
1126	public boolean setIdentityKeyTrust(Account account, String fingerprint, XmppAxolotlSession.Trust trust) {
1127		SQLiteDatabase db = this.getWritableDatabase();
1128		return setIdentityKeyTrust(db, account, fingerprint, trust);
1129	}
1130
1131	private boolean setIdentityKeyTrust(SQLiteDatabase db, Account account, String fingerprint, XmppAxolotlSession.Trust trust) {
1132		String[] selectionArgs = {
1133				account.getUuid(),
1134				fingerprint
1135		};
1136		ContentValues values = new ContentValues();
1137		values.put(SQLiteAxolotlStore.TRUSTED, trust.getCode());
1138		int rows = db.update(SQLiteAxolotlStore.IDENTITIES_TABLENAME, values,
1139				SQLiteAxolotlStore.ACCOUNT + " = ? AND "
1140						+ SQLiteAxolotlStore.FINGERPRINT + " = ? ",
1141				selectionArgs);
1142		return rows == 1;
1143	}
1144
1145	public boolean setIdentityKeyCertificate(Account account, String fingerprint, X509Certificate x509Certificate) {
1146		SQLiteDatabase db = this.getWritableDatabase();
1147		String[] selectionArgs = {
1148				account.getUuid(),
1149				fingerprint
1150		};
1151		try {
1152			ContentValues values = new ContentValues();
1153			values.put(SQLiteAxolotlStore.CERTIFICATE, x509Certificate.getEncoded());
1154			return db.update(SQLiteAxolotlStore.IDENTITIES_TABLENAME, values,
1155					SQLiteAxolotlStore.ACCOUNT + " = ? AND "
1156							+ SQLiteAxolotlStore.FINGERPRINT + " = ? ",
1157					selectionArgs) == 1;
1158		} catch (CertificateEncodingException e) {
1159			Log.d(Config.LOGTAG, "could not encode certificate");
1160			return false;
1161		}
1162	}
1163
1164	public X509Certificate getIdentityKeyCertifcate(Account account, String fingerprint) {
1165		SQLiteDatabase db = this.getReadableDatabase();
1166		String[] selectionArgs = {
1167				account.getUuid(),
1168				fingerprint
1169		};
1170		String[] colums = {SQLiteAxolotlStore.CERTIFICATE};
1171		String selection = SQLiteAxolotlStore.ACCOUNT + " = ? AND " + SQLiteAxolotlStore.FINGERPRINT + " = ? ";
1172		Cursor cursor = db.query(SQLiteAxolotlStore.IDENTITIES_TABLENAME, colums, selection, selectionArgs, null, null, null);
1173		if (cursor.getCount() < 1) {
1174			return null;
1175		} else {
1176			cursor.moveToFirst();
1177			byte[] certificate = cursor.getBlob(cursor.getColumnIndex(SQLiteAxolotlStore.CERTIFICATE));
1178			cursor.close();
1179			if (certificate == null || certificate.length == 0) {
1180				return null;
1181			}
1182			try {
1183				CertificateFactory certificateFactory = CertificateFactory.getInstance("X.509");
1184				return (X509Certificate) certificateFactory.generateCertificate(new ByteArrayInputStream(certificate));
1185			} catch (CertificateException e) {
1186				Log.d(Config.LOGTAG,"certificate exception "+e.getMessage());
1187				return null;
1188			}
1189		}
1190	}
1191
1192	public void storeIdentityKey(Account account, String name, IdentityKey identityKey) {
1193		storeIdentityKey(account, name, false, identityKey.getFingerprint().replaceAll("\\s", ""), Base64.encodeToString(identityKey.serialize(), Base64.DEFAULT));
1194	}
1195
1196	public void storeOwnIdentityKeyPair(Account account, IdentityKeyPair identityKeyPair) {
1197		storeIdentityKey(account, account.getJid().toBareJid().toPreppedString(), true, identityKeyPair.getPublicKey().getFingerprint().replaceAll("\\s", ""), Base64.encodeToString(identityKeyPair.serialize(), Base64.DEFAULT), XmppAxolotlSession.Trust.TRUSTED);
1198	}
1199
1200
1201	public void recreateAxolotlDb(SQLiteDatabase db) {
1202		Log.d(Config.LOGTAG, AxolotlService.LOGPREFIX + " : " + ">>> (RE)CREATING AXOLOTL DATABASE <<<");
1203		db.execSQL("DROP TABLE IF EXISTS " + SQLiteAxolotlStore.SESSION_TABLENAME);
1204		db.execSQL(CREATE_SESSIONS_STATEMENT);
1205		db.execSQL("DROP TABLE IF EXISTS " + SQLiteAxolotlStore.PREKEY_TABLENAME);
1206		db.execSQL(CREATE_PREKEYS_STATEMENT);
1207		db.execSQL("DROP TABLE IF EXISTS " + SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME);
1208		db.execSQL(CREATE_SIGNED_PREKEYS_STATEMENT);
1209		db.execSQL("DROP TABLE IF EXISTS " + SQLiteAxolotlStore.IDENTITIES_TABLENAME);
1210		db.execSQL(CREATE_IDENTITIES_STATEMENT);
1211	}
1212
1213	public void wipeAxolotlDb(Account account) {
1214		String accountName = account.getUuid();
1215		Log.d(Config.LOGTAG, AxolotlService.getLogprefix(account) + ">>> WIPING AXOLOTL DATABASE FOR ACCOUNT " + accountName + " <<<");
1216		SQLiteDatabase db = this.getWritableDatabase();
1217		String[] deleteArgs = {
1218				accountName
1219		};
1220		db.delete(SQLiteAxolotlStore.SESSION_TABLENAME,
1221				SQLiteAxolotlStore.ACCOUNT + " = ?",
1222				deleteArgs);
1223		db.delete(SQLiteAxolotlStore.PREKEY_TABLENAME,
1224				SQLiteAxolotlStore.ACCOUNT + " = ?",
1225				deleteArgs);
1226		db.delete(SQLiteAxolotlStore.SIGNED_PREKEY_TABLENAME,
1227				SQLiteAxolotlStore.ACCOUNT + " = ?",
1228				deleteArgs);
1229		db.delete(SQLiteAxolotlStore.IDENTITIES_TABLENAME,
1230				SQLiteAxolotlStore.ACCOUNT + " = ?",
1231				deleteArgs);
1232	}
1233
1234	public boolean startTimeCountExceedsThreshold() {
1235		SQLiteDatabase db = this.getWritableDatabase();
1236		long cleanBeforeTimestamp = System.currentTimeMillis() - Config.FREQUENT_RESTARTS_DETECTION_WINDOW;
1237		db.execSQL("delete from "+START_TIMES_TABLE+" where timestamp < "+cleanBeforeTimestamp);
1238		ContentValues values = new ContentValues();
1239		values.put("timestamp",System.currentTimeMillis());
1240		db.insert(START_TIMES_TABLE,null,values);
1241		String[] columns = new String[]{"count(timestamp)"};
1242		Cursor cursor = db.query(START_TIMES_TABLE,columns,null,null,null,null,null);
1243		int count;
1244		if (cursor.moveToFirst()) {
1245			count = cursor.getInt(0);
1246		} else {
1247			count = 0;
1248		}
1249		cursor.close();
1250		return count >= Config.FREQUENT_RESTARTS_THRESHOLD;
1251	}
1252
1253	public void clearStartTimeCounter() {
1254		SQLiteDatabase db = this.getWritableDatabase();
1255		db.execSQL("delete from "+START_TIMES_TABLE);
1256	}
1257}