884 lines
31 KiB
Dart
884 lines
31 KiB
Dart
/*
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* Famedly Matrix SDK
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* Copyright (C) 2019, 2020 Famedly GmbH
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License as
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* published by the Free Software Foundation, either version 3 of the
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* License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License
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* along with this program. If not, see <https://www.gnu.org/licenses/>.
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*/
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import 'dart:convert';
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import 'package:olm/olm.dart' as olm;
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import 'package:pedantic/pedantic.dart';
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import './encryption.dart';
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import './utils/outbound_group_session.dart';
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import './utils/session_key.dart';
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import '../famedlysdk.dart';
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import '../matrix_api.dart';
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import '../src/database/database.dart';
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import '../src/utils/logs.dart';
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import '../src/utils/run_in_background.dart';
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const MEGOLM_KEY = 'm.megolm_backup.v1';
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class KeyManager {
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final Encryption encryption;
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Client get client => encryption.client;
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final outgoingShareRequests = <String, KeyManagerKeyShareRequest>{};
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final incomingShareRequests = <String, KeyManagerKeyShareRequest>{};
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final _inboundGroupSessions = <String, Map<String, SessionKey>>{};
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final _outboundGroupSessions = <String, OutboundGroupSession>{};
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final Set<String> _loadedOutboundGroupSessions = <String>{};
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final Set<String> _requestedSessionIds = <String>{};
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KeyManager(this.encryption) {
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encryption.ssss.setValidator(MEGOLM_KEY, (String secret) async {
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final keyObj = olm.PkDecryption();
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try {
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final info = await client.getRoomKeysBackup();
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if (info.algorithm != RoomKeysAlgorithmType.v1Curve25519AesSha2) {
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return false;
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}
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if (keyObj.init_with_private_key(base64.decode(secret)) ==
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info.authData['public_key']) {
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_requestedSessionIds.clear();
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return true;
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}
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return false;
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} catch (_) {
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return false;
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} finally {
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keyObj.free();
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}
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});
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}
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bool get enabled => client.accountData[MEGOLM_KEY] != null;
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/// clear all cached inbound group sessions. useful for testing
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void clearInboundGroupSessions() {
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_inboundGroupSessions.clear();
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}
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void setInboundGroupSession(String roomId, String sessionId, String senderKey,
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Map<String, dynamic> content,
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{bool forwarded = false,
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Map<String, String> senderClaimedKeys,
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bool uploaded = false}) {
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senderClaimedKeys ??= <String, String>{};
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if (!senderClaimedKeys.containsKey('ed25519')) {
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final device = client.getUserDeviceKeysByCurve25519Key(senderKey);
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if (device != null) {
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senderClaimedKeys['ed25519'] = device.ed25519Key;
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}
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}
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final oldSession =
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getInboundGroupSession(roomId, sessionId, senderKey, otherRooms: false);
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if (content['algorithm'] != 'm.megolm.v1.aes-sha2') {
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return;
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}
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olm.InboundGroupSession inboundGroupSession;
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try {
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inboundGroupSession = olm.InboundGroupSession();
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if (forwarded) {
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inboundGroupSession.import_session(content['session_key']);
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} else {
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inboundGroupSession.create(content['session_key']);
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}
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} catch (e, s) {
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inboundGroupSession.free();
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Logs.error(
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'[LibOlm] Could not create new InboundGroupSession: ' + e.toString(),
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s);
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return;
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}
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final newSession = SessionKey(
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content: content,
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inboundGroupSession: inboundGroupSession,
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indexes: {},
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roomId: roomId,
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sessionId: sessionId,
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key: client.userID,
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senderKey: senderKey,
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senderClaimedKeys: senderClaimedKeys,
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);
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final oldFirstIndex =
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oldSession?.inboundGroupSession?.first_known_index() ?? 0;
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final newFirstIndex = newSession.inboundGroupSession.first_known_index();
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if (oldSession == null ||
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newFirstIndex < oldFirstIndex ||
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(oldFirstIndex == newFirstIndex &&
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newSession.forwardingCurve25519KeyChain.length <
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oldSession.forwardingCurve25519KeyChain.length)) {
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// use new session
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oldSession?.dispose();
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} else {
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// we are gonna keep our old session
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newSession.dispose();
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return;
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}
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if (!_inboundGroupSessions.containsKey(roomId)) {
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_inboundGroupSessions[roomId] = <String, SessionKey>{};
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}
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_inboundGroupSessions[roomId][sessionId] = newSession;
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client.database
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?.storeInboundGroupSession(
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client.id,
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roomId,
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sessionId,
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inboundGroupSession.pickle(client.userID),
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json.encode(content),
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json.encode({}),
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senderKey,
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json.encode(senderClaimedKeys),
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)
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?.then((_) {
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if (uploaded) {
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client.database
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.markInboundGroupSessionAsUploaded(client.id, roomId, sessionId);
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}
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});
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// TODO: somehow try to decrypt last message again
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final room = client.getRoomById(roomId);
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if (room != null) {
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room.onSessionKeyReceived.add(sessionId);
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}
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}
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SessionKey getInboundGroupSession(
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String roomId, String sessionId, String senderKey,
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{bool otherRooms = true}) {
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if (_inboundGroupSessions.containsKey(roomId) &&
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_inboundGroupSessions[roomId].containsKey(sessionId)) {
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final sess = _inboundGroupSessions[roomId][sessionId];
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if (sess.senderKey != senderKey && sess.senderKey.isNotEmpty) {
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return null;
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}
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return sess;
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}
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if (!otherRooms) {
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return null;
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}
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// search if this session id is *somehow* found in another room
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for (final val in _inboundGroupSessions.values) {
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if (val.containsKey(sessionId)) {
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final sess = val[sessionId];
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if (sess.senderKey != senderKey && sess.senderKey.isNotEmpty) {
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return null;
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}
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return sess;
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}
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}
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return null;
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}
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/// Loads an inbound group session
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Future<SessionKey> loadInboundGroupSession(
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String roomId, String sessionId, String senderKey) async {
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if (roomId == null || sessionId == null || senderKey == null) {
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return null;
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}
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if (_inboundGroupSessions.containsKey(roomId) &&
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_inboundGroupSessions[roomId].containsKey(sessionId)) {
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final sess = _inboundGroupSessions[roomId][sessionId];
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if (sess.senderKey != senderKey && sess.senderKey.isNotEmpty) {
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return null; // sender keys do not match....better not do anything
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}
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return sess; // nothing to do
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}
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final session = await client.database
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?.getDbInboundGroupSession(client.id, roomId, sessionId);
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if (session == null) {
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final room = client.getRoomById(roomId);
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final requestIdent = '$roomId|$sessionId|$senderKey';
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if (client.enableE2eeRecovery &&
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room != null &&
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!_requestedSessionIds.contains(requestIdent)) {
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// do e2ee recovery
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_requestedSessionIds.add(requestIdent);
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unawaited(request(room, sessionId, senderKey, askOnlyOwnDevices: true));
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}
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return null;
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}
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if (!_inboundGroupSessions.containsKey(roomId)) {
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_inboundGroupSessions[roomId] = <String, SessionKey>{};
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}
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final sess = SessionKey.fromDb(session, client.userID);
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if (!sess.isValid ||
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(sess.senderKey.isNotEmpty && sess.senderKey != senderKey)) {
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return null;
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}
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_inboundGroupSessions[roomId][sessionId] = sess;
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return sess;
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}
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/// clear all cached inbound group sessions. useful for testing
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void clearOutboundGroupSessions() {
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_outboundGroupSessions.clear();
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}
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/// Clears the existing outboundGroupSession but first checks if the participating
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/// devices have been changed. Returns false if the session has not been cleared because
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/// it wasn't necessary.
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Future<bool> clearOutboundGroupSession(String roomId,
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{bool wipe = false}) async {
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final room = client.getRoomById(roomId);
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final sess = getOutboundGroupSession(roomId);
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if (room == null || sess == null) {
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return true;
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}
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if (!wipe) {
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// first check if the devices in the room changed
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final deviceKeys = await room.getUserDeviceKeys();
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deviceKeys.removeWhere((k) => k.blocked);
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final deviceKeyIds = deviceKeys.map((k) => k.deviceId).toList();
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deviceKeyIds.sort();
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if (deviceKeyIds.toString() != sess.devices.toString()) {
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wipe = true;
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}
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// next check if it needs to be rotated
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final encryptionContent = room.getState(EventTypes.Encryption)?.content;
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final maxMessages = encryptionContent != null &&
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encryptionContent['rotation_period_msgs'] is int
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? encryptionContent['rotation_period_msgs']
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: 100;
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final maxAge = encryptionContent != null &&
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encryptionContent['rotation_period_ms'] is int
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? encryptionContent['rotation_period_ms']
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: 604800000; // default of one week
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if (sess.sentMessages >= maxMessages ||
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sess.creationTime
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.add(Duration(milliseconds: maxAge))
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.isBefore(DateTime.now())) {
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wipe = true;
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}
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if (!wipe) {
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return false;
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}
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}
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sess.dispose();
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_outboundGroupSessions.remove(roomId);
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await client.database?.removeOutboundGroupSession(client.id, roomId);
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return true;
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}
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Future<void> storeOutboundGroupSession(
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String roomId, OutboundGroupSession sess) async {
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if (sess == null) {
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return;
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}
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await client.database?.storeOutboundGroupSession(
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client.id,
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roomId,
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sess.outboundGroupSession.pickle(client.userID),
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json.encode(sess.devices),
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sess.creationTime,
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sess.sentMessages);
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}
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Future<OutboundGroupSession> createOutboundGroupSession(String roomId) async {
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await clearOutboundGroupSession(roomId, wipe: true);
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final room = client.getRoomById(roomId);
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if (room == null) {
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return null;
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}
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final deviceKeys = await room.getUserDeviceKeys();
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deviceKeys.removeWhere((k) => k.blocked);
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final deviceKeyIds = deviceKeys.map((k) => k.deviceId).toList();
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deviceKeyIds.sort();
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final outboundGroupSession = olm.OutboundGroupSession();
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try {
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outboundGroupSession.create();
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} catch (e, s) {
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outboundGroupSession.free();
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Logs.error(
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'[LibOlm] Unable to create new outboundGroupSession: ' + e.toString(),
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s);
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return null;
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}
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final rawSession = <String, dynamic>{
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'algorithm': 'm.megolm.v1.aes-sha2',
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'room_id': room.id,
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'session_id': outboundGroupSession.session_id(),
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'session_key': outboundGroupSession.session_key(),
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};
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setInboundGroupSession(
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roomId, rawSession['session_id'], encryption.identityKey, rawSession);
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final sess = OutboundGroupSession(
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devices: deviceKeyIds,
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creationTime: DateTime.now(),
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outboundGroupSession: outboundGroupSession,
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sentMessages: 0,
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key: client.userID,
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);
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try {
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await client.sendToDeviceEncrypted(deviceKeys, 'm.room_key', rawSession);
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await storeOutboundGroupSession(roomId, sess);
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_outboundGroupSessions[roomId] = sess;
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} catch (e, s) {
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Logs.error(
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'[LibOlm] Unable to send the session key to the participating devices: ' +
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e.toString(),
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s);
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sess.dispose();
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return null;
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}
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return sess;
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}
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OutboundGroupSession getOutboundGroupSession(String roomId) {
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return _outboundGroupSessions[roomId];
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}
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Future<void> loadOutboundGroupSession(String roomId) async {
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if (_loadedOutboundGroupSessions.contains(roomId) ||
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_outboundGroupSessions.containsKey(roomId) ||
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client.database == null) {
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return; // nothing to do
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}
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_loadedOutboundGroupSessions.add(roomId);
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final session =
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await client.database.getDbOutboundGroupSession(client.id, roomId);
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if (session == null) {
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return;
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}
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final sess = OutboundGroupSession.fromDb(session, client.userID);
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if (!sess.isValid) {
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return;
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}
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_outboundGroupSessions[roomId] = sess;
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}
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Future<bool> isCached() async {
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if (!enabled) {
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return false;
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}
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return (await encryption.ssss.getCached(MEGOLM_KEY)) != null;
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}
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Future<void> loadFromResponse(RoomKeys keys) async {
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if (!(await isCached())) {
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return;
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}
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final privateKey =
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base64.decode(await encryption.ssss.getCached(MEGOLM_KEY));
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final decryption = olm.PkDecryption();
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final info = await client.getRoomKeysBackup();
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String backupPubKey;
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try {
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backupPubKey = decryption.init_with_private_key(privateKey);
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if (backupPubKey == null ||
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info.algorithm != RoomKeysAlgorithmType.v1Curve25519AesSha2 ||
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info.authData['public_key'] != backupPubKey) {
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return;
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}
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for (final roomEntry in keys.rooms.entries) {
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final roomId = roomEntry.key;
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for (final sessionEntry in roomEntry.value.sessions.entries) {
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final sessionId = sessionEntry.key;
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final session = sessionEntry.value;
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final firstMessageIndex = session.firstMessageIndex;
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final forwardedCount = session.forwardedCount;
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final isVerified = session.isVerified;
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final sessionData = session.sessionData;
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if (firstMessageIndex == null ||
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forwardedCount == null ||
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isVerified == null ||
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!(sessionData is Map)) {
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continue;
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}
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Map<String, dynamic> decrypted;
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try {
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decrypted = json.decode(decryption.decrypt(sessionData['ephemeral'],
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sessionData['mac'], sessionData['ciphertext']));
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} catch (e, s) {
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Logs.error(
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'[LibOlm] Error decrypting room key: ' + e.toString(), s);
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}
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if (decrypted != null) {
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decrypted['session_id'] = sessionId;
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decrypted['room_id'] = roomId;
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setInboundGroupSession(
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roomId, sessionId, decrypted['sender_key'], decrypted,
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forwarded: true,
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senderClaimedKeys: decrypted['sender_claimed_keys'] != null
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? Map<String, String>.from(decrypted['sender_claimed_keys'])
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: null,
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uploaded: true);
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}
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}
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}
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} finally {
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decryption.free();
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}
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}
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Future<void> loadSingleKey(String roomId, String sessionId) async {
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final info = await client.getRoomKeysBackup();
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final ret =
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await client.getRoomKeysSingleKey(roomId, sessionId, info.version);
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final keys = RoomKeys.fromJson({
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'rooms': {
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roomId: {
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'sessions': {
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sessionId: ret.toJson(),
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},
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},
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},
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});
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await loadFromResponse(keys);
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}
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/// Request a certain key from another device
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Future<void> request(
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Room room,
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String sessionId,
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String senderKey, {
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bool tryOnlineBackup = true,
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bool askOnlyOwnDevices = false,
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}) async {
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if (tryOnlineBackup) {
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// let's first check our online key backup store thingy...
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var hadPreviously =
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getInboundGroupSession(room.id, sessionId, senderKey) != null;
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try {
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await loadSingleKey(room.id, sessionId);
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} catch (err, stacktrace) {
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if (err is MatrixException && err.errcode == 'M_NOT_FOUND') {
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Logs.info(
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'[KeyManager] Key not in online key backup, requesting it from other devices...');
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} else {
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Logs.error(
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'[KeyManager] Failed to access online key backup: ' +
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err.toString(),
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stacktrace);
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}
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}
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if (!hadPreviously &&
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getInboundGroupSession(room.id, sessionId, senderKey) != null) {
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return; // we managed to load the session from online backup, no need to care about it now
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}
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}
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try {
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// while we just send the to-device event to '*', we still need to save the
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// devices themself to know where to send the cancel to after receiving a reply
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final devices = await room.getUserDeviceKeys();
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if (askOnlyOwnDevices) {
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devices.removeWhere((d) => d.userId != client.userID);
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}
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final requestId = client.generateUniqueTransactionId();
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final request = KeyManagerKeyShareRequest(
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requestId: requestId,
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devices: devices,
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room: room,
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sessionId: sessionId,
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senderKey: senderKey,
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);
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final userList = await room.requestParticipants();
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await client.sendToDevicesOfUserIds(
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userList.map<String>((u) => u.id).toSet(),
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'm.room_key_request',
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{
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'action': 'request',
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'body': {
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'algorithm': 'm.megolm.v1.aes-sha2',
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'room_id': room.id,
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'sender_key': senderKey,
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'session_id': sessionId,
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},
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'request_id': requestId,
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'requesting_device_id': client.deviceID,
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},
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);
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outgoingShareRequests[request.requestId] = request;
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} catch (e, s) {
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Logs.error(
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'[Key Manager] Sending key verification request failed: ' +
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e.toString(),
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s);
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}
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}
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|
|
bool _isUploadingKeys = false;
|
|
Future<void> backgroundTasks() async {
|
|
if (_isUploadingKeys || client.database == null) {
|
|
return;
|
|
}
|
|
_isUploadingKeys = true;
|
|
try {
|
|
if (!(await isCached())) {
|
|
return; // we can't backup anyways
|
|
}
|
|
final dbSessions =
|
|
await client.database.getInboundGroupSessionsToUpload().get();
|
|
if (dbSessions.isEmpty) {
|
|
return; // nothing to do
|
|
}
|
|
final privateKey =
|
|
base64.decode(await encryption.ssss.getCached(MEGOLM_KEY));
|
|
// decryption is needed to calculate the public key and thus see if the claimed information is in fact valid
|
|
final decryption = olm.PkDecryption();
|
|
final info = await client.getRoomKeysBackup();
|
|
String backupPubKey;
|
|
try {
|
|
backupPubKey = decryption.init_with_private_key(privateKey);
|
|
|
|
if (backupPubKey == null ||
|
|
info.algorithm != RoomKeysAlgorithmType.v1Curve25519AesSha2 ||
|
|
info.authData['public_key'] != backupPubKey) {
|
|
return;
|
|
}
|
|
final args = _GenerateUploadKeysArgs(
|
|
pubkey: backupPubKey,
|
|
dbSessions: <_DbInboundGroupSessionBundle>[],
|
|
userId: client.userID,
|
|
);
|
|
// we need to calculate verified beforehand, as else we pass a closure to an isolate
|
|
// with 500 keys they do, however, noticably block the UI, which is why we give brief async suspentions in here
|
|
// so that the event loop can progress
|
|
var i = 0;
|
|
for (final dbSession in dbSessions) {
|
|
final device =
|
|
client.getUserDeviceKeysByCurve25519Key(dbSession.senderKey);
|
|
args.dbSessions.add(_DbInboundGroupSessionBundle(
|
|
dbSession: dbSession,
|
|
verified: device?.verified ?? false,
|
|
));
|
|
i++;
|
|
if (i > 10) {
|
|
await Future.delayed(Duration(milliseconds: 1));
|
|
i = 0;
|
|
}
|
|
}
|
|
final roomKeys =
|
|
await runInBackground<RoomKeys, _GenerateUploadKeysArgs>(
|
|
_generateUploadKeys, args);
|
|
Logs.info('[Key Manager] Uploading ${dbSessions.length} room keys...');
|
|
// upload the payload...
|
|
await client.storeRoomKeys(info.version, roomKeys);
|
|
// and now finally mark all the keys as uploaded
|
|
// no need to optimze this, as we only run it so seldomly and almost never with many keys at once
|
|
for (final dbSession in dbSessions) {
|
|
await client.database.markInboundGroupSessionAsUploaded(
|
|
client.id, dbSession.roomId, dbSession.sessionId);
|
|
}
|
|
} finally {
|
|
decryption.free();
|
|
}
|
|
} catch (e, s) {
|
|
Logs.error('[Key Manager] Error uploading room keys: ' + e.toString(), s);
|
|
} finally {
|
|
_isUploadingKeys = false;
|
|
}
|
|
}
|
|
|
|
/// Handle an incoming to_device event that is related to key sharing
|
|
Future<void> handleToDeviceEvent(ToDeviceEvent event) async {
|
|
if (event.type == 'm.room_key_request') {
|
|
if (!(event.content['request_id'] is String)) {
|
|
return; // invalid event
|
|
}
|
|
if (event.content['action'] == 'request') {
|
|
// we are *receiving* a request
|
|
Logs.info('[KeyManager] Received key sharing request...');
|
|
if (!event.content.containsKey('body')) {
|
|
Logs.info('[KeyManager] No body, doing nothing');
|
|
return; // no body
|
|
}
|
|
if (!client.userDeviceKeys.containsKey(event.sender) ||
|
|
!client.userDeviceKeys[event.sender].deviceKeys
|
|
.containsKey(event.content['requesting_device_id'])) {
|
|
Logs.info('[KeyManager] Device not found, doing nothing');
|
|
return; // device not found
|
|
}
|
|
final device = client.userDeviceKeys[event.sender]
|
|
.deviceKeys[event.content['requesting_device_id']];
|
|
if (device.userId == client.userID &&
|
|
device.deviceId == client.deviceID) {
|
|
Logs.info('[KeyManager] Request is by ourself, ignoring');
|
|
return; // ignore requests by ourself
|
|
}
|
|
final room = client.getRoomById(event.content['body']['room_id']);
|
|
if (room == null) {
|
|
Logs.info('[KeyManager] Unknown room, ignoring');
|
|
return; // unknown room
|
|
}
|
|
final sessionId = event.content['body']['session_id'];
|
|
final senderKey = event.content['body']['sender_key'];
|
|
// okay, let's see if we have this session at all
|
|
if ((await loadInboundGroupSession(room.id, sessionId, senderKey)) ==
|
|
null) {
|
|
Logs.info('[KeyManager] Unknown session, ignoring');
|
|
return; // we don't have this session anyways
|
|
}
|
|
final request = KeyManagerKeyShareRequest(
|
|
requestId: event.content['request_id'],
|
|
devices: [device],
|
|
room: room,
|
|
sessionId: sessionId,
|
|
senderKey: senderKey,
|
|
);
|
|
if (incomingShareRequests.containsKey(request.requestId)) {
|
|
Logs.info('[KeyManager] Already processed this request, ignoring');
|
|
return; // we don't want to process one and the same request multiple times
|
|
}
|
|
incomingShareRequests[request.requestId] = request;
|
|
final roomKeyRequest =
|
|
RoomKeyRequest.fromToDeviceEvent(event, this, request);
|
|
if (device.userId == client.userID &&
|
|
device.verified &&
|
|
!device.blocked) {
|
|
Logs.info('[KeyManager] All checks out, forwarding key...');
|
|
// alright, we can forward the key
|
|
await roomKeyRequest.forwardKey();
|
|
} else {
|
|
Logs.info(
|
|
'[KeyManager] Asking client, if the key should be forwarded');
|
|
client.onRoomKeyRequest
|
|
.add(roomKeyRequest); // let the client handle this
|
|
}
|
|
} else if (event.content['action'] == 'request_cancellation') {
|
|
// we got told to cancel an incoming request
|
|
if (!incomingShareRequests.containsKey(event.content['request_id'])) {
|
|
return; // we don't know this request anyways
|
|
}
|
|
// alright, let's just cancel this request
|
|
final request = incomingShareRequests[event.content['request_id']];
|
|
request.canceled = true;
|
|
incomingShareRequests.remove(request.requestId);
|
|
}
|
|
} else if (event.type == 'm.forwarded_room_key') {
|
|
// we *received* an incoming key request
|
|
if (event.encryptedContent == null) {
|
|
return; // event wasn't encrypted, this is a security risk
|
|
}
|
|
final request = outgoingShareRequests.values.firstWhere(
|
|
(r) =>
|
|
r.room.id == event.content['room_id'] &&
|
|
r.sessionId == event.content['session_id'] &&
|
|
r.senderKey == event.content['sender_key'],
|
|
orElse: () => null);
|
|
if (request == null || request.canceled) {
|
|
return; // no associated request found or it got canceled
|
|
}
|
|
final device = request.devices.firstWhere(
|
|
(d) =>
|
|
d.userId == event.sender &&
|
|
d.curve25519Key == event.encryptedContent['sender_key'],
|
|
orElse: () => null);
|
|
if (device == null) {
|
|
return; // someone we didn't send our request to replied....better ignore this
|
|
}
|
|
// we add the sender key to the forwarded key chain
|
|
if (!(event.content['forwarding_curve25519_key_chain'] is List)) {
|
|
event.content['forwarding_curve25519_key_chain'] = <String>[];
|
|
}
|
|
event.content['forwarding_curve25519_key_chain']
|
|
.add(event.encryptedContent['sender_key']);
|
|
// TODO: verify that the keys work to decrypt a message
|
|
// alright, all checks out, let's go ahead and store this session
|
|
setInboundGroupSession(
|
|
request.room.id, request.sessionId, request.senderKey, event.content,
|
|
forwarded: true,
|
|
senderClaimedKeys: {
|
|
'ed25519': event.content['sender_claimed_ed25519_key'],
|
|
});
|
|
request.devices.removeWhere(
|
|
(k) => k.userId == device.userId && k.deviceId == device.deviceId);
|
|
outgoingShareRequests.remove(request.requestId);
|
|
// send cancel to all other devices
|
|
if (request.devices.isEmpty) {
|
|
return; // no need to send any cancellation
|
|
}
|
|
// Send with send-to-device messaging
|
|
final sendToDeviceMessage = {
|
|
'action': 'request_cancellation',
|
|
'request_id': request.requestId,
|
|
'requesting_device_id': client.deviceID,
|
|
};
|
|
var data = <String, Map<String, Map<String, dynamic>>>{};
|
|
for (final device in request.devices) {
|
|
if (!data.containsKey(device.userId)) {
|
|
data[device.userId] = {};
|
|
}
|
|
data[device.userId][device.deviceId] = sendToDeviceMessage;
|
|
}
|
|
await client.sendToDevice(
|
|
'm.room_key_request',
|
|
client.generateUniqueTransactionId(),
|
|
data,
|
|
);
|
|
} else if (event.type == 'm.room_key') {
|
|
if (event.encryptedContent == null) {
|
|
return; // the event wasn't encrypted, this is a security risk;
|
|
}
|
|
final String roomId = event.content['room_id'];
|
|
final String sessionId = event.content['session_id'];
|
|
if (client.userDeviceKeys.containsKey(event.sender) &&
|
|
client.userDeviceKeys[event.sender].deviceKeys
|
|
.containsKey(event.content['requesting_device_id'])) {
|
|
event.content['sender_claimed_ed25519_key'] = client
|
|
.userDeviceKeys[event.sender]
|
|
.deviceKeys[event.content['requesting_device_id']]
|
|
.ed25519Key;
|
|
}
|
|
setInboundGroupSession(roomId, sessionId,
|
|
event.encryptedContent['sender_key'], event.content,
|
|
forwarded: false);
|
|
}
|
|
}
|
|
|
|
void dispose() {
|
|
for (final sess in _outboundGroupSessions.values) {
|
|
sess.dispose();
|
|
}
|
|
for (final entries in _inboundGroupSessions.values) {
|
|
for (final sess in entries.values) {
|
|
sess.dispose();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
class KeyManagerKeyShareRequest {
|
|
final String requestId;
|
|
final List<DeviceKeys> devices;
|
|
final Room room;
|
|
final String sessionId;
|
|
final String senderKey;
|
|
bool canceled;
|
|
|
|
KeyManagerKeyShareRequest(
|
|
{this.requestId,
|
|
this.devices,
|
|
this.room,
|
|
this.sessionId,
|
|
this.senderKey,
|
|
this.canceled = false});
|
|
}
|
|
|
|
class RoomKeyRequest extends ToDeviceEvent {
|
|
KeyManager keyManager;
|
|
KeyManagerKeyShareRequest request;
|
|
RoomKeyRequest.fromToDeviceEvent(ToDeviceEvent toDeviceEvent,
|
|
KeyManager keyManager, KeyManagerKeyShareRequest request) {
|
|
this.keyManager = keyManager;
|
|
this.request = request;
|
|
sender = toDeviceEvent.sender;
|
|
content = toDeviceEvent.content;
|
|
type = toDeviceEvent.type;
|
|
}
|
|
|
|
Room get room => request.room;
|
|
|
|
DeviceKeys get requestingDevice => request.devices.first;
|
|
|
|
Future<void> forwardKey() async {
|
|
if (request.canceled) {
|
|
keyManager.incomingShareRequests.remove(request.requestId);
|
|
return; // request is canceled, don't send anything
|
|
}
|
|
var room = this.room;
|
|
final session = await keyManager.loadInboundGroupSession(
|
|
room.id, request.sessionId, request.senderKey);
|
|
var message = session.content;
|
|
message['forwarding_curve25519_key_chain'] =
|
|
List<String>.from(session.forwardingCurve25519KeyChain);
|
|
|
|
message['sender_key'] =
|
|
(session.senderKey != null && session.senderKey.isNotEmpty)
|
|
? session.senderKey
|
|
: request.senderKey;
|
|
message['sender_claimed_ed25519_key'] =
|
|
session.senderClaimedKeys['ed25519'] ??
|
|
(session.forwardingCurve25519KeyChain.isEmpty
|
|
? keyManager.encryption.fingerprintKey
|
|
: null);
|
|
message['session_key'] = session.inboundGroupSession
|
|
.export_session(session.inboundGroupSession.first_known_index());
|
|
// send the actual reply of the key back to the requester
|
|
await keyManager.client.sendToDeviceEncrypted(
|
|
[requestingDevice],
|
|
'm.forwarded_room_key',
|
|
message,
|
|
);
|
|
keyManager.incomingShareRequests.remove(request.requestId);
|
|
}
|
|
}
|
|
|
|
RoomKeys _generateUploadKeys(_GenerateUploadKeysArgs args) {
|
|
final enc = olm.PkEncryption();
|
|
try {
|
|
enc.set_recipient_key(args.pubkey);
|
|
// first we generate the payload to upload all the session keys in this chunk
|
|
final roomKeys = RoomKeys();
|
|
for (final dbSession in args.dbSessions) {
|
|
final sess = SessionKey.fromDb(dbSession.dbSession, args.userId);
|
|
if (!sess.isValid) {
|
|
continue;
|
|
}
|
|
// create the room if it doesn't exist
|
|
if (!roomKeys.rooms.containsKey(sess.roomId)) {
|
|
roomKeys.rooms[sess.roomId] = RoomKeysRoom();
|
|
}
|
|
// generate the encrypted content
|
|
final payload = <String, dynamic>{
|
|
'algorithm': 'm.megolm.v1.aes-sha2',
|
|
'forwarding_curve25519_key_chain': sess.forwardingCurve25519KeyChain,
|
|
'sender_key': sess.senderKey,
|
|
'sender_clencaimed_keys': sess.senderClaimedKeys,
|
|
'session_key': sess.inboundGroupSession
|
|
.export_session(sess.inboundGroupSession.first_known_index()),
|
|
};
|
|
// encrypt the content
|
|
final encrypted = enc.encrypt(json.encode(payload));
|
|
// fetch the device, if available...
|
|
//final device = args.client.getUserDeviceKeysByCurve25519Key(sess.senderKey);
|
|
// aaaand finally add the session key to our payload
|
|
roomKeys.rooms[sess.roomId].sessions[sess.sessionId] = RoomKeysSingleKey(
|
|
firstMessageIndex: sess.inboundGroupSession.first_known_index(),
|
|
forwardedCount: sess.forwardingCurve25519KeyChain.length,
|
|
isVerified: dbSession.verified, //device?.verified ?? false,
|
|
sessionData: {
|
|
'ephemeral': encrypted.ephemeral,
|
|
'ciphertext': encrypted.ciphertext,
|
|
'mac': encrypted.mac,
|
|
},
|
|
);
|
|
}
|
|
return roomKeys;
|
|
} catch (e, s) {
|
|
Logs.error('[Key Manager] Error generating payload ' + e.toString(), s);
|
|
rethrow;
|
|
} finally {
|
|
enc.free();
|
|
}
|
|
}
|
|
|
|
class _DbInboundGroupSessionBundle {
|
|
_DbInboundGroupSessionBundle({this.dbSession, this.verified});
|
|
|
|
DbInboundGroupSession dbSession;
|
|
bool verified;
|
|
}
|
|
|
|
class _GenerateUploadKeysArgs {
|
|
_GenerateUploadKeysArgs({this.pubkey, this.dbSessions, this.userId});
|
|
|
|
String pubkey;
|
|
List<_DbInboundGroupSessionBundle> dbSessions;
|
|
String userId;
|
|
}
|