1205 lines
34 KiB
Dart
1205 lines
34 KiB
Dart
/*
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* Famedly Matrix SDK
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* Copyright (C) 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:async';
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import 'dart:typed_data';
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import 'package:canonical_json/canonical_json.dart';
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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 '../../famedlysdk.dart';
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import '../../matrix_api.dart';
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import '../../src/utils/logs.dart';
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import '../encryption.dart';
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/*
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+-------------+ +-----------+
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| AliceDevice | | BobDevice |
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+-------------+ +-----------+
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| |
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| (m.key.verification.request) |
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|-------------------------------->| (ASK FOR VERIFICATION REQUEST)
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| |
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| (m.key.verification.ready) |
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|<--------------------------------|
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| |
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| (m.key.verification.start) | we will probably not send this
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|<--------------------------------| for simplicities sake
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| |
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| m.key.verification.start |
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|-------------------------------->| (ASK FOR VERIFICATION REQUEST)
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| |
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| m.key.verification.accept |
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|<--------------------------------|
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| |
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| m.key.verification.key |
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|-------------------------------->|
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| |
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| m.key.verification.key |
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|<--------------------------------|
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| |
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| COMPARE EMOJI / NUMBERS |
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| |
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| m.key.verification.mac |
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|-------------------------------->| success
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| |
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| m.key.verification.mac |
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success |<--------------------------------|
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| |
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*/
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enum KeyVerificationState {
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askAccept,
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askSSSS,
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waitingAccept,
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askSas,
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waitingSas,
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done,
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error
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}
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enum KeyVerificationMethod { emoji, numbers }
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List<String> _intersect(List<String> a, List<dynamic> b) {
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if (b == null || a == null) {
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return [];
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}
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final res = <String>[];
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for (final v in a) {
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if (b.contains(v)) {
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res.add(v);
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}
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}
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return res;
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}
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List<int> _bytesToInt(Uint8List bytes, int totalBits) {
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final ret = <int>[];
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var current = 0;
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var numBits = 0;
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for (final byte in bytes) {
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for (final bit in [7, 6, 5, 4, 3, 2, 1, 0]) {
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numBits++;
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if ((byte & (1 << bit)) > 0) {
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current += 1 << (totalBits - numBits);
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}
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if (numBits >= totalBits) {
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ret.add(current);
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current = 0;
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numBits = 0;
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}
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}
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}
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return ret;
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}
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_KeyVerificationMethod _makeVerificationMethod(
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String type, KeyVerification request) {
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if (type == 'm.sas.v1') {
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return _KeyVerificationMethodSas(request: request);
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}
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throw 'Unkown method type';
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}
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class KeyVerification {
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String transactionId;
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final Encryption encryption;
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Client get client => encryption.client;
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final Room room;
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final String userId;
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void Function() onUpdate;
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String get deviceId => _deviceId;
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String _deviceId;
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bool startedVerification = false;
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_KeyVerificationMethod method;
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List<String> possibleMethods;
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Map<String, dynamic> startPaylaod;
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String _nextAction;
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List<SignableKey> _verifiedDevices;
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DateTime lastActivity;
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String lastStep;
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KeyVerificationState state = KeyVerificationState.waitingAccept;
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bool canceled = false;
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String canceledCode;
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String canceledReason;
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KeyVerification(
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{this.encryption,
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this.room,
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this.userId,
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String deviceId,
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this.onUpdate}) {
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lastActivity = DateTime.now();
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_deviceId ??= deviceId;
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}
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void dispose() {
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Logs.info('[Key Verification] disposing object...');
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method?.dispose();
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}
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static String getTransactionId(Map<String, dynamic> payload) {
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return payload['transaction_id'] ??
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(payload['m.relates_to'] is Map
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? payload['m.relates_to']['event_id']
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: null);
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}
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List<String> get knownVerificationMethods {
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final methods = <String>[];
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if (client.verificationMethods.contains(KeyVerificationMethod.numbers) ||
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client.verificationMethods.contains(KeyVerificationMethod.emoji)) {
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methods.add('m.sas.v1');
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}
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return methods;
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}
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Future<void> sendStart() async {
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await send('m.key.verification.request', {
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'methods': knownVerificationMethods,
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if (room == null) 'timestamp': DateTime.now().millisecondsSinceEpoch,
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});
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startedVerification = true;
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setState(KeyVerificationState.waitingAccept);
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lastActivity = DateTime.now();
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}
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Future<void> start() async {
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if (room == null) {
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transactionId = client.generateUniqueTransactionId();
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}
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if (encryption.crossSigning.enabled &&
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!(await encryption.crossSigning.isCached()) &&
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!client.isUnknownSession) {
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setState(KeyVerificationState.askSSSS);
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_nextAction = 'request';
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} else {
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await sendStart();
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}
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}
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bool _handlePayloadLock = false;
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Future<void> handlePayload(String type, Map<String, dynamic> payload,
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[String eventId]) async {
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while (_handlePayloadLock) {
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await Future.delayed(Duration(milliseconds: 50));
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}
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_handlePayloadLock = true;
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Logs.info(
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'[Key Verification] Received type ${type}: ' + payload.toString());
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try {
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var thisLastStep = lastStep;
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switch (type) {
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case 'm.key.verification.request':
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_deviceId ??= payload['from_device'];
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transactionId ??= eventId ?? payload['transaction_id'];
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// verify the timestamp
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final now = DateTime.now();
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final verifyTime =
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DateTime.fromMillisecondsSinceEpoch(payload['timestamp']);
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if (now.subtract(Duration(minutes: 10)).isAfter(verifyTime) ||
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now.add(Duration(minutes: 5)).isBefore(verifyTime)) {
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// if the request is more than 20min in the past we just silently fail it
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// to not generate too many cancels
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await cancel('m.timeout',
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now.subtract(Duration(minutes: 20)).isAfter(verifyTime));
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return;
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}
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// verify it has a method we can use
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possibleMethods =
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_intersect(knownVerificationMethods, payload['methods']);
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if (possibleMethods.isEmpty) {
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// reject it outright
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await cancel('m.unknown_method');
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return;
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}
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setState(KeyVerificationState.askAccept);
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break;
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case 'm.key.verification.ready':
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_deviceId ??= payload['from_device'];
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possibleMethods =
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_intersect(knownVerificationMethods, payload['methods']);
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if (possibleMethods.isEmpty) {
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// reject it outright
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await cancel('m.unknown_method');
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return;
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}
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// as both parties can send a start, the last step being "ready" is race-condition prone
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// as such, we better set it *before* we send our start
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lastStep = type;
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// TODO: Pick method?
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method = _makeVerificationMethod(possibleMethods.first, this);
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await method.sendStart();
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setState(KeyVerificationState.waitingAccept);
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break;
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case 'm.key.verification.start':
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_deviceId ??= payload['from_device'];
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transactionId ??= eventId ?? payload['transaction_id'];
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if (method != null) {
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// the other side sent us a start, even though we already sent one
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if (payload['method'] == method.type) {
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// same method. Determine priority
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final ourEntry = '${client.userID}|${client.deviceID}';
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final entries = [ourEntry, '${userId}|${deviceId}'];
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entries.sort();
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if (entries.first == ourEntry) {
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// our start won, nothing to do
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return;
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} else {
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// the other start won, let's hand off
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startedVerification = false; // it is now as if they started
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thisLastStep = lastStep =
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'm.key.verification.request'; // we fake the last step
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method.dispose(); // in case anything got created already
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}
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} else {
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// methods don't match up, let's cancel this
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await cancel('m.unexpected_message');
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return;
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}
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}
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if (!(await verifyLastStep(['m.key.verification.request', null]))) {
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return; // abort
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}
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if (!knownVerificationMethods.contains(payload['method'])) {
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await cancel('m.unknown_method');
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return;
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}
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method = _makeVerificationMethod(payload['method'], this);
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if (lastStep == null) {
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// validate the start time
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if (room != null) {
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// we just silently ignore in-room-verification starts
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await cancel('m.unknown_method', true);
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return;
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}
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// validate the specific payload
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if (!method.validateStart(payload)) {
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await cancel('m.unknown_method');
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return;
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}
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startPaylaod = payload;
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setState(KeyVerificationState.askAccept);
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} else {
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Logs.info('handling start in method.....');
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await method.handlePayload(type, payload);
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}
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break;
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case 'm.key.verification.done':
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// do nothing
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break;
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case 'm.key.verification.cancel':
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canceled = true;
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canceledCode = payload['code'];
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canceledReason = payload['reason'];
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setState(KeyVerificationState.error);
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break;
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default:
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if (method != null) {
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await method.handlePayload(type, payload);
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} else {
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await cancel('m.invalid_message');
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}
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break;
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}
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if (lastStep == thisLastStep) {
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lastStep = type;
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}
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} catch (err, stacktrace) {
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Logs.error(
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'[Key Verification] An error occured: ' + err.toString(), stacktrace);
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await cancel('m.invalid_message');
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} finally {
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_handlePayloadLock = false;
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}
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}
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void otherDeviceAccepted() {
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canceled = true;
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canceledCode = 'm.accepted';
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canceledReason = 'm.accepted';
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setState(KeyVerificationState.error);
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}
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Future<void> openSSSS(
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{String passphrase, String recoveryKey, bool skip = false}) async {
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final next = () {
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if (_nextAction == 'request') {
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sendStart();
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} else if (_nextAction == 'done') {
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if (_verifiedDevices != null) {
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// and now let's sign them all in the background
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encryption.crossSigning.sign(_verifiedDevices);
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}
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setState(KeyVerificationState.done);
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}
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};
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if (skip) {
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next();
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return;
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}
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final handle = encryption.ssss.open('m.cross_signing.user_signing');
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await handle.unlock(passphrase: passphrase, recoveryKey: recoveryKey);
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await handle.maybeCacheAll();
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next();
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}
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/// called when the user accepts an incoming verification
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Future<void> acceptVerification() async {
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if (!(await verifyLastStep(
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['m.key.verification.request', 'm.key.verification.start']))) {
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return;
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}
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setState(KeyVerificationState.waitingAccept);
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if (lastStep == 'm.key.verification.request') {
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// we need to send a ready event
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await send('m.key.verification.ready', {
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'methods': possibleMethods,
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});
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} else {
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// we need to send an accept event
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await method.handlePayload('m.key.verification.start', startPaylaod);
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}
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}
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/// called when the user rejects an incoming verification
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Future<void> rejectVerification() async {
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if (!(await verifyLastStep(
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['m.key.verification.request', 'm.key.verification.start']))) {
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return;
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}
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await cancel('m.user');
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}
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Future<void> acceptSas() async {
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if (method is _KeyVerificationMethodSas) {
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await (method as _KeyVerificationMethodSas).acceptSas();
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}
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}
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Future<void> rejectSas() async {
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if (method is _KeyVerificationMethodSas) {
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await (method as _KeyVerificationMethodSas).rejectSas();
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}
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}
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List<int> get sasNumbers {
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if (method is _KeyVerificationMethodSas) {
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return _bytesToInt((method as _KeyVerificationMethodSas).makeSas(5), 13)
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.map((n) => n + 1000)
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.toList();
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}
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return [];
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}
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List<String> get sasTypes {
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if (method is _KeyVerificationMethodSas) {
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return (method as _KeyVerificationMethodSas).authenticationTypes;
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}
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return [];
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}
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List<KeyVerificationEmoji> get sasEmojis {
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if (method is _KeyVerificationMethodSas) {
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final numbers =
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_bytesToInt((method as _KeyVerificationMethodSas).makeSas(6), 6);
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return numbers.map((n) => KeyVerificationEmoji(n)).toList().sublist(0, 7);
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}
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return [];
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}
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Future<void> maybeRequestSSSSSecrets([int i = 0]) async {
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final requestInterval = <int>[10, 60];
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if ((!encryption.crossSigning.enabled ||
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(encryption.crossSigning.enabled &&
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(await encryption.crossSigning.isCached()))) &&
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(!encryption.keyManager.enabled ||
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(encryption.keyManager.enabled &&
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(await encryption.keyManager.isCached())))) {
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// no need to request cache, we already have it
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return;
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}
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unawaited(encryption.ssss
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.maybeRequestAll(_verifiedDevices.whereType<DeviceKeys>().toList()));
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if (requestInterval.length <= i) {
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return;
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}
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Timer(Duration(seconds: requestInterval[i]),
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() => maybeRequestSSSSSecrets(i + 1));
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}
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Future<void> verifyKeys(Map<String, String> keys,
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Future<bool> Function(String, SignableKey) verifier) async {
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_verifiedDevices = <SignableKey>[];
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if (!client.userDeviceKeys.containsKey(userId)) {
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await cancel('m.key_mismatch');
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return;
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}
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for (final entry in keys.entries) {
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final keyId = entry.key;
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final verifyDeviceId = keyId.substring('ed25519:'.length);
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final keyInfo = entry.value;
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final key = client.userDeviceKeys[userId].getKey(verifyDeviceId);
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if (key != null) {
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if (!(await verifier(keyInfo, key))) {
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await cancel('m.key_mismatch');
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return;
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}
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_verifiedDevices.add(key);
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}
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}
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// okay, we reached this far, so all the devices are verified!
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var verifiedMasterKey = false;
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final wasUnknownSession = client.isUnknownSession;
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for (final key in _verifiedDevices) {
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await key.setVerified(
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true, false); // we don't want to sign the keys juuuust yet
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if (key is CrossSigningKey && key.usage.contains('master')) {
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verifiedMasterKey = true;
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}
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}
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if (verifiedMasterKey && userId == client.userID) {
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// it was our own master key, let's request the cross signing keys
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// we do it in the background, thus no await needed here
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unawaited(maybeRequestSSSSSecrets());
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}
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await send('m.key.verification.done', {});
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var askingSSSS = false;
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if (encryption.crossSigning.enabled &&
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encryption.crossSigning.signable(_verifiedDevices)) {
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// these keys can be signed! Let's do so
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if (await encryption.crossSigning.isCached()) {
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// and now let's sign them all in the background
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unawaited(encryption.crossSigning.sign(_verifiedDevices));
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} else if (!wasUnknownSession) {
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askingSSSS = true;
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}
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}
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if (askingSSSS) {
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setState(KeyVerificationState.askSSSS);
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_nextAction = 'done';
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} else {
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setState(KeyVerificationState.done);
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}
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}
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Future<bool> verifyActivity() async {
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if (lastActivity != null &&
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lastActivity.add(Duration(minutes: 10)).isAfter(DateTime.now())) {
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lastActivity = DateTime.now();
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return true;
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}
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await cancel('m.timeout');
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return false;
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}
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Future<bool> verifyLastStep(List<String> checkLastStep) async {
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if (!(await verifyActivity())) {
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return false;
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}
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if (checkLastStep.contains(lastStep)) {
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return true;
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}
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await cancel('m.unexpected_message');
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return false;
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}
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|
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Future<void> cancel([String code = 'm.unknown', bool quiet = false]) async {
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if (!quiet && (deviceId != null || room != null)) {
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await send('m.key.verification.cancel', {
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'reason': code,
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'code': code,
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});
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}
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canceled = true;
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canceledCode = code;
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setState(KeyVerificationState.error);
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}
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|
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void makePayload(Map<String, dynamic> payload) {
|
|
payload['from_device'] = client.deviceID;
|
|
if (transactionId != null) {
|
|
if (room != null) {
|
|
payload['m.relates_to'] = {
|
|
'rel_type': 'm.reference',
|
|
'event_id': transactionId,
|
|
};
|
|
} else {
|
|
payload['transaction_id'] = transactionId;
|
|
}
|
|
}
|
|
}
|
|
|
|
Future<void> send(String type, Map<String, dynamic> payload) async {
|
|
makePayload(payload);
|
|
Logs.info('[Key Verification] Sending type ${type}: ' + payload.toString());
|
|
if (room != null) {
|
|
Logs.info(
|
|
'[Key Verification] Sending to ${userId} in room ${room.id}...');
|
|
if (['m.key.verification.request'].contains(type)) {
|
|
payload['msgtype'] = type;
|
|
payload['to'] = userId;
|
|
payload['body'] =
|
|
'Attempting verification request. (${type}) Apparently your client doesn\'t support this';
|
|
type = EventTypes.Message;
|
|
}
|
|
final newTransactionId = await room.sendEvent(payload, type: type);
|
|
if (transactionId == null) {
|
|
transactionId = newTransactionId;
|
|
encryption.keyVerificationManager.addRequest(this);
|
|
}
|
|
} else {
|
|
Logs.info(
|
|
'[Key Verification] Sending to ${userId} device ${deviceId}...');
|
|
await client.sendToDeviceEncrypted(
|
|
[client.userDeviceKeys[userId].deviceKeys[deviceId]], type, payload);
|
|
}
|
|
}
|
|
|
|
void setState(KeyVerificationState newState) {
|
|
if (state != KeyVerificationState.error) {
|
|
state = newState;
|
|
}
|
|
if (onUpdate != null) {
|
|
onUpdate();
|
|
}
|
|
}
|
|
}
|
|
|
|
abstract class _KeyVerificationMethod {
|
|
KeyVerification request;
|
|
Encryption get encryption => request.encryption;
|
|
Client get client => request.client;
|
|
_KeyVerificationMethod({this.request});
|
|
|
|
Future<void> handlePayload(String type, Map<String, dynamic> payload);
|
|
bool validateStart(Map<String, dynamic> payload) {
|
|
return false;
|
|
}
|
|
|
|
String _type;
|
|
String get type => _type;
|
|
|
|
Future<void> sendStart();
|
|
void dispose() {}
|
|
}
|
|
|
|
const KNOWN_KEY_AGREEMENT_PROTOCOLS = ['curve25519-hkdf-sha256', 'curve25519'];
|
|
const KNOWN_HASHES = ['sha256'];
|
|
const KNOWN_MESSAGE_AUTHENTIFICATION_CODES = ['hkdf-hmac-sha256'];
|
|
|
|
class _KeyVerificationMethodSas extends _KeyVerificationMethod {
|
|
_KeyVerificationMethodSas({KeyVerification request})
|
|
: super(request: request);
|
|
|
|
@override
|
|
final _type = 'm.sas.v1';
|
|
|
|
String keyAgreementProtocol;
|
|
String hash;
|
|
String messageAuthenticationCode;
|
|
List<String> authenticationTypes;
|
|
String startCanonicalJson;
|
|
String commitment;
|
|
String theirPublicKey;
|
|
Map<String, dynamic> macPayload;
|
|
olm.SAS sas;
|
|
|
|
@override
|
|
void dispose() {
|
|
sas?.free();
|
|
}
|
|
|
|
List<String> get knownAuthentificationTypes {
|
|
final types = <String>[];
|
|
if (request.client.verificationMethods
|
|
.contains(KeyVerificationMethod.emoji)) {
|
|
types.add('emoji');
|
|
}
|
|
if (request.client.verificationMethods
|
|
.contains(KeyVerificationMethod.numbers)) {
|
|
types.add('decimal');
|
|
}
|
|
return types;
|
|
}
|
|
|
|
@override
|
|
Future<void> handlePayload(String type, Map<String, dynamic> payload) async {
|
|
try {
|
|
switch (type) {
|
|
case 'm.key.verification.start':
|
|
if (!(await request.verifyLastStep(
|
|
['m.key.verification.request', 'm.key.verification.start']))) {
|
|
return; // abort
|
|
}
|
|
if (!validateStart(payload)) {
|
|
await request.cancel('m.unknown_method');
|
|
return;
|
|
}
|
|
await _sendAccept();
|
|
break;
|
|
case 'm.key.verification.accept':
|
|
if (!(await request.verifyLastStep(['m.key.verification.ready']))) {
|
|
return;
|
|
}
|
|
if (!_handleAccept(payload)) {
|
|
await request.cancel('m.unknown_method');
|
|
return;
|
|
}
|
|
await _sendKey();
|
|
break;
|
|
case 'm.key.verification.key':
|
|
if (!(await request.verifyLastStep(
|
|
['m.key.verification.accept', 'm.key.verification.start']))) {
|
|
return;
|
|
}
|
|
_handleKey(payload);
|
|
if (request.lastStep == 'm.key.verification.start') {
|
|
// we need to send our key
|
|
await _sendKey();
|
|
} else {
|
|
// we already sent our key, time to verify the commitment being valid
|
|
if (!_validateCommitment()) {
|
|
await request.cancel('m.mismatched_commitment');
|
|
return;
|
|
}
|
|
}
|
|
request.setState(KeyVerificationState.askSas);
|
|
break;
|
|
case 'm.key.verification.mac':
|
|
if (!(await request.verifyLastStep(['m.key.verification.key']))) {
|
|
return;
|
|
}
|
|
macPayload = payload;
|
|
if (request.state == KeyVerificationState.waitingSas) {
|
|
await _processMac();
|
|
}
|
|
break;
|
|
}
|
|
} catch (err, stacktrace) {
|
|
Logs.error('[Key Verification SAS] An error occured: ' + err.toString(),
|
|
stacktrace);
|
|
if (request.deviceId != null) {
|
|
await request.cancel('m.invalid_message');
|
|
}
|
|
}
|
|
}
|
|
|
|
Future<void> acceptSas() async {
|
|
await _sendMac();
|
|
request.setState(KeyVerificationState.waitingSas);
|
|
if (macPayload != null) {
|
|
await _processMac();
|
|
}
|
|
}
|
|
|
|
Future<void> rejectSas() async {
|
|
await request.cancel('m.mismatched_sas');
|
|
}
|
|
|
|
@override
|
|
Future<void> sendStart() async {
|
|
final payload = <String, dynamic>{
|
|
'method': type,
|
|
'key_agreement_protocols': KNOWN_KEY_AGREEMENT_PROTOCOLS,
|
|
'hashes': KNOWN_HASHES,
|
|
'message_authentication_codes': KNOWN_MESSAGE_AUTHENTIFICATION_CODES,
|
|
'short_authentication_string': knownAuthentificationTypes,
|
|
};
|
|
request.makePayload(payload);
|
|
// We just store the canonical json in here for later verification
|
|
startCanonicalJson = String.fromCharCodes(canonicalJson.encode(payload));
|
|
await request.send('m.key.verification.start', payload);
|
|
}
|
|
|
|
@override
|
|
bool validateStart(Map<String, dynamic> payload) {
|
|
if (payload['method'] != type) {
|
|
return false;
|
|
}
|
|
final possibleKeyAgreementProtocols = _intersect(
|
|
KNOWN_KEY_AGREEMENT_PROTOCOLS, payload['key_agreement_protocols']);
|
|
if (possibleKeyAgreementProtocols.isEmpty) {
|
|
return false;
|
|
}
|
|
keyAgreementProtocol = possibleKeyAgreementProtocols.first;
|
|
final possibleHashes = _intersect(KNOWN_HASHES, payload['hashes']);
|
|
if (possibleHashes.isEmpty) {
|
|
return false;
|
|
}
|
|
hash = possibleHashes.first;
|
|
final possibleMessageAuthenticationCodes = _intersect(
|
|
KNOWN_MESSAGE_AUTHENTIFICATION_CODES,
|
|
payload['message_authentication_codes']);
|
|
if (possibleMessageAuthenticationCodes.isEmpty) {
|
|
return false;
|
|
}
|
|
messageAuthenticationCode = possibleMessageAuthenticationCodes.first;
|
|
final possibleAuthenticationTypes = _intersect(
|
|
knownAuthentificationTypes, payload['short_authentication_string']);
|
|
if (possibleAuthenticationTypes.isEmpty) {
|
|
return false;
|
|
}
|
|
authenticationTypes = possibleAuthenticationTypes;
|
|
startCanonicalJson = String.fromCharCodes(canonicalJson.encode(payload));
|
|
return true;
|
|
}
|
|
|
|
Future<void> _sendAccept() async {
|
|
sas = olm.SAS();
|
|
commitment = _makeCommitment(sas.get_pubkey(), startCanonicalJson);
|
|
await request.send('m.key.verification.accept', {
|
|
'method': type,
|
|
'key_agreement_protocol': keyAgreementProtocol,
|
|
'hash': hash,
|
|
'message_authentication_code': messageAuthenticationCode,
|
|
'short_authentication_string': authenticationTypes,
|
|
'commitment': commitment,
|
|
});
|
|
}
|
|
|
|
bool _handleAccept(Map<String, dynamic> payload) {
|
|
if (!KNOWN_KEY_AGREEMENT_PROTOCOLS
|
|
.contains(payload['key_agreement_protocol'])) {
|
|
return false;
|
|
}
|
|
keyAgreementProtocol = payload['key_agreement_protocol'];
|
|
if (!KNOWN_HASHES.contains(payload['hash'])) {
|
|
return false;
|
|
}
|
|
hash = payload['hash'];
|
|
if (!KNOWN_MESSAGE_AUTHENTIFICATION_CODES
|
|
.contains(payload['message_authentication_code'])) {
|
|
return false;
|
|
}
|
|
messageAuthenticationCode = payload['message_authentication_code'];
|
|
final possibleAuthenticationTypes = _intersect(
|
|
knownAuthentificationTypes, payload['short_authentication_string']);
|
|
if (possibleAuthenticationTypes.isEmpty) {
|
|
return false;
|
|
}
|
|
authenticationTypes = possibleAuthenticationTypes;
|
|
commitment = payload['commitment'];
|
|
sas = olm.SAS();
|
|
return true;
|
|
}
|
|
|
|
Future<void> _sendKey() async {
|
|
await request.send('m.key.verification.key', {
|
|
'key': sas.get_pubkey(),
|
|
});
|
|
}
|
|
|
|
void _handleKey(Map<String, dynamic> payload) {
|
|
theirPublicKey = payload['key'];
|
|
sas.set_their_key(payload['key']);
|
|
}
|
|
|
|
bool _validateCommitment() {
|
|
final checkCommitment = _makeCommitment(theirPublicKey, startCanonicalJson);
|
|
return commitment == checkCommitment;
|
|
}
|
|
|
|
Uint8List makeSas(int bytes) {
|
|
var sasInfo = '';
|
|
if (keyAgreementProtocol == 'curve25519-hkdf-sha256') {
|
|
final ourInfo =
|
|
'${client.userID}|${client.deviceID}|${sas.get_pubkey()}|';
|
|
final theirInfo =
|
|
'${request.userId}|${request.deviceId}|${theirPublicKey}|';
|
|
sasInfo = 'MATRIX_KEY_VERIFICATION_SAS|' +
|
|
(request.startedVerification
|
|
? ourInfo + theirInfo
|
|
: theirInfo + ourInfo) +
|
|
request.transactionId;
|
|
} else if (keyAgreementProtocol == 'curve25519') {
|
|
final ourInfo = client.userID + client.deviceID;
|
|
final theirInfo = request.userId + request.deviceId;
|
|
sasInfo = 'MATRIX_KEY_VERIFICATION_SAS' +
|
|
(request.startedVerification
|
|
? ourInfo + theirInfo
|
|
: theirInfo + ourInfo) +
|
|
request.transactionId;
|
|
} else {
|
|
throw 'Unknown key agreement protocol';
|
|
}
|
|
return sas.generate_bytes(sasInfo, bytes);
|
|
}
|
|
|
|
Future<void> _sendMac() async {
|
|
final baseInfo = 'MATRIX_KEY_VERIFICATION_MAC' +
|
|
client.userID +
|
|
client.deviceID +
|
|
request.userId +
|
|
request.deviceId +
|
|
request.transactionId;
|
|
final mac = <String, String>{};
|
|
final keyList = <String>[];
|
|
|
|
// now add all the keys we want the other to verify
|
|
// for now it is just our device key, once we have cross-signing
|
|
// we would also add the cross signing key here
|
|
final deviceKeyId = 'ed25519:${client.deviceID}';
|
|
mac[deviceKeyId] =
|
|
_calculateMac(encryption.fingerprintKey, baseInfo + deviceKeyId);
|
|
keyList.add(deviceKeyId);
|
|
|
|
final masterKey = client.userDeviceKeys.containsKey(client.userID)
|
|
? client.userDeviceKeys[client.userID].masterKey
|
|
: null;
|
|
if (masterKey != null && masterKey.verified) {
|
|
// we have our own master key verified, let's send it!
|
|
final masterKeyId = 'ed25519:${masterKey.publicKey}';
|
|
mac[masterKeyId] =
|
|
_calculateMac(masterKey.publicKey, baseInfo + masterKeyId);
|
|
keyList.add(masterKeyId);
|
|
}
|
|
|
|
keyList.sort();
|
|
final keys = _calculateMac(keyList.join(','), baseInfo + 'KEY_IDS');
|
|
await request.send('m.key.verification.mac', {
|
|
'mac': mac,
|
|
'keys': keys,
|
|
});
|
|
}
|
|
|
|
Future<void> _processMac() async {
|
|
final payload = macPayload;
|
|
final baseInfo = 'MATRIX_KEY_VERIFICATION_MAC' +
|
|
request.userId +
|
|
request.deviceId +
|
|
client.userID +
|
|
client.deviceID +
|
|
request.transactionId;
|
|
|
|
final keyList = payload['mac'].keys.toList();
|
|
keyList.sort();
|
|
if (payload['keys'] !=
|
|
_calculateMac(keyList.join(','), baseInfo + 'KEY_IDS')) {
|
|
await request.cancel('m.key_mismatch');
|
|
return;
|
|
}
|
|
|
|
if (!client.userDeviceKeys.containsKey(request.userId)) {
|
|
await request.cancel('m.key_mismatch');
|
|
return;
|
|
}
|
|
final mac = <String, String>{};
|
|
for (final entry in payload['mac'].entries) {
|
|
if (entry.value is String) {
|
|
mac[entry.key] = entry.value;
|
|
}
|
|
}
|
|
await request.verifyKeys(mac, (String mac, SignableKey key) async {
|
|
return mac ==
|
|
_calculateMac(key.ed25519Key, baseInfo + 'ed25519:' + key.identifier);
|
|
});
|
|
}
|
|
|
|
String _makeCommitment(String pubKey, String canonicalJson) {
|
|
if (hash == 'sha256') {
|
|
final olmutil = olm.Utility();
|
|
final ret = olmutil.sha256(pubKey + canonicalJson);
|
|
olmutil.free();
|
|
return ret;
|
|
}
|
|
throw 'Unknown hash method';
|
|
}
|
|
|
|
String _calculateMac(String input, String info) {
|
|
if (messageAuthenticationCode == 'hkdf-hmac-sha256') {
|
|
return sas.calculate_mac(input, info);
|
|
} else {
|
|
throw 'Unknown message authentification code';
|
|
}
|
|
}
|
|
}
|
|
|
|
const _emojiMap = [
|
|
{
|
|
'emoji': '\u{1F436}',
|
|
'name': 'Dog',
|
|
},
|
|
{
|
|
'emoji': '\u{1F431}',
|
|
'name': 'Cat',
|
|
},
|
|
{
|
|
'emoji': '\u{1F981}',
|
|
'name': 'Lion',
|
|
},
|
|
{
|
|
'emoji': '\u{1F40E}',
|
|
'name': 'Horse',
|
|
},
|
|
{
|
|
'emoji': '\u{1F984}',
|
|
'name': 'Unicorn',
|
|
},
|
|
{
|
|
'emoji': '\u{1F437}',
|
|
'name': 'Pig',
|
|
},
|
|
{
|
|
'emoji': '\u{1F418}',
|
|
'name': 'Elephant',
|
|
},
|
|
{
|
|
'emoji': '\u{1F430}',
|
|
'name': 'Rabbit',
|
|
},
|
|
{
|
|
'emoji': '\u{1F43C}',
|
|
'name': 'Panda',
|
|
},
|
|
{
|
|
'emoji': '\u{1F413}',
|
|
'name': 'Rooster',
|
|
},
|
|
{
|
|
'emoji': '\u{1F427}',
|
|
'name': 'Penguin',
|
|
},
|
|
{
|
|
'emoji': '\u{1F422}',
|
|
'name': 'Turtle',
|
|
},
|
|
{
|
|
'emoji': '\u{1F41F}',
|
|
'name': 'Fish',
|
|
},
|
|
{
|
|
'emoji': '\u{1F419}',
|
|
'name': 'Octopus',
|
|
},
|
|
{
|
|
'emoji': '\u{1F98B}',
|
|
'name': 'Butterfly',
|
|
},
|
|
{
|
|
'emoji': '\u{1F337}',
|
|
'name': 'Flower',
|
|
},
|
|
{
|
|
'emoji': '\u{1F333}',
|
|
'name': 'Tree',
|
|
},
|
|
{
|
|
'emoji': '\u{1F335}',
|
|
'name': 'Cactus',
|
|
},
|
|
{
|
|
'emoji': '\u{1F344}',
|
|
'name': 'Mushroom',
|
|
},
|
|
{
|
|
'emoji': '\u{1F30F}',
|
|
'name': 'Globe',
|
|
},
|
|
{
|
|
'emoji': '\u{1F319}',
|
|
'name': 'Moon',
|
|
},
|
|
{
|
|
'emoji': '\u{2601}\u{FE0F}',
|
|
'name': 'Cloud',
|
|
},
|
|
{
|
|
'emoji': '\u{1F525}',
|
|
'name': 'Fire',
|
|
},
|
|
{
|
|
'emoji': '\u{1F34C}',
|
|
'name': 'Banana',
|
|
},
|
|
{
|
|
'emoji': '\u{1F34E}',
|
|
'name': 'Apple',
|
|
},
|
|
{
|
|
'emoji': '\u{1F353}',
|
|
'name': 'Strawberry',
|
|
},
|
|
{
|
|
'emoji': '\u{1F33D}',
|
|
'name': 'Corn',
|
|
},
|
|
{
|
|
'emoji': '\u{1F355}',
|
|
'name': 'Pizza',
|
|
},
|
|
{
|
|
'emoji': '\u{1F382}',
|
|
'name': 'Cake',
|
|
},
|
|
{
|
|
'emoji': '\u{2764}\u{FE0F}',
|
|
'name': 'Heart',
|
|
},
|
|
{
|
|
'emoji': '\u{1F600}',
|
|
'name': 'Smiley',
|
|
},
|
|
{
|
|
'emoji': '\u{1F916}',
|
|
'name': 'Robot',
|
|
},
|
|
{
|
|
'emoji': '\u{1F3A9}',
|
|
'name': 'Hat',
|
|
},
|
|
{
|
|
'emoji': '\u{1F453}',
|
|
'name': 'Glasses',
|
|
},
|
|
{
|
|
'emoji': '\u{1F527}',
|
|
'name': 'Spanner',
|
|
},
|
|
{
|
|
'emoji': '\u{1F385}',
|
|
'name': 'Santa',
|
|
},
|
|
{
|
|
'emoji': '\u{1F44D}',
|
|
'name': 'Thumbs Up',
|
|
},
|
|
{
|
|
'emoji': '\u{2602}\u{FE0F}',
|
|
'name': 'Umbrella',
|
|
},
|
|
{
|
|
'emoji': '\u{231B}',
|
|
'name': 'Hourglass',
|
|
},
|
|
{
|
|
'emoji': '\u{23F0}',
|
|
'name': 'Clock',
|
|
},
|
|
{
|
|
'emoji': '\u{1F381}',
|
|
'name': 'Gift',
|
|
},
|
|
{
|
|
'emoji': '\u{1F4A1}',
|
|
'name': 'Light Bulb',
|
|
},
|
|
{
|
|
'emoji': '\u{1F4D5}',
|
|
'name': 'Book',
|
|
},
|
|
{
|
|
'emoji': '\u{270F}\u{FE0F}',
|
|
'name': 'Pencil',
|
|
},
|
|
{
|
|
'emoji': '\u{1F4CE}',
|
|
'name': 'Paperclip',
|
|
},
|
|
{
|
|
'emoji': '\u{2702}\u{FE0F}',
|
|
'name': 'Scissors',
|
|
},
|
|
{
|
|
'emoji': '\u{1F512}',
|
|
'name': 'Lock',
|
|
},
|
|
{
|
|
'emoji': '\u{1F511}',
|
|
'name': 'Key',
|
|
},
|
|
{
|
|
'emoji': '\u{1F528}',
|
|
'name': 'Hammer',
|
|
},
|
|
{
|
|
'emoji': '\u{260E}\u{FE0F}',
|
|
'name': 'Telephone',
|
|
},
|
|
{
|
|
'emoji': '\u{1F3C1}',
|
|
'name': 'Flag',
|
|
},
|
|
{
|
|
'emoji': '\u{1F682}',
|
|
'name': 'Train',
|
|
},
|
|
{
|
|
'emoji': '\u{1F6B2}',
|
|
'name': 'Bicycle',
|
|
},
|
|
{
|
|
'emoji': '\u{2708}\u{FE0F}',
|
|
'name': 'Aeroplane',
|
|
},
|
|
{
|
|
'emoji': '\u{1F680}',
|
|
'name': 'Rocket',
|
|
},
|
|
{
|
|
'emoji': '\u{1F3C6}',
|
|
'name': 'Trophy',
|
|
},
|
|
{
|
|
'emoji': '\u{26BD}',
|
|
'name': 'Ball',
|
|
},
|
|
{
|
|
'emoji': '\u{1F3B8}',
|
|
'name': 'Guitar',
|
|
},
|
|
{
|
|
'emoji': '\u{1F3BA}',
|
|
'name': 'Trumpet',
|
|
},
|
|
{
|
|
'emoji': '\u{1F514}',
|
|
'name': 'Bell',
|
|
},
|
|
{
|
|
'emoji': '\u{2693}',
|
|
'name': 'Anchor',
|
|
},
|
|
{
|
|
'emoji': '\u{1F3A7}',
|
|
'name': 'Headphones',
|
|
},
|
|
{
|
|
'emoji': '\u{1F4C1}',
|
|
'name': 'Folder',
|
|
},
|
|
{
|
|
'emoji': '\u{1F4CC}',
|
|
'name': 'Pin',
|
|
},
|
|
];
|
|
|
|
class KeyVerificationEmoji {
|
|
final int number;
|
|
KeyVerificationEmoji(this.number);
|
|
|
|
String get emoji => _emojiMap[number]['emoji'];
|
|
String get name => _emojiMap[number]['name'];
|
|
}
|