feat: Begin work on the OmemoManager interface
This commit is contained in:
parent
06707d1a34
commit
b48665c357
@ -12,6 +12,7 @@ export 'src/omemo/events.dart';
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export 'src/omemo/fingerprint.dart';
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export 'src/omemo/ratchet_map_key.dart';
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export 'src/omemo/sessionmanager.dart';
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export 'src/omemo/stanza.dart';
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export 'src/trust/base.dart';
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export 'src/trust/btbv.dart';
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export 'src/x3dh/x3dh.dart';
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@ -13,7 +13,6 @@ import 'package:omemo_dart/src/protobuf/omemo_message.dart';
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const maxSkip = 1000;
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class RatchetStep {
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const RatchetStep(this.header, this.ciphertext);
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final OmemoMessage header;
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final List<int> ciphertext;
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@ -21,7 +20,6 @@ class RatchetStep {
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@immutable
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class SkippedKey {
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const SkippedKey(this.dh, this.n);
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factory SkippedKey.fromJson(Map<String, dynamic> data) {
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@ -54,7 +52,6 @@ class SkippedKey {
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}
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class OmemoDoubleRatchet {
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OmemoDoubleRatchet(
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this.dhs, // DHs
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this.dhr, // DHr
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@ -221,7 +218,7 @@ class OmemoDoubleRatchet {
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ik,
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ad,
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{},
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false,
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true,
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kexTimestamp,
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null,
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);
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@ -1,45 +1,46 @@
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abstract class OmemoException {}
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/// Triggered during X3DH if the signature if the SPK does verify to the actual SPK.
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class InvalidSignatureException implements Exception {
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class InvalidSignatureException extends OmemoException implements Exception {
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String errMsg() => 'The signature of the SPK does not match the provided signature';
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}
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/// Triggered by the Double Ratchet if the computed HMAC does not match the attached HMAC.
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/// Triggered by the Session Manager if the computed HMAC does not match the attached HMAC.
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class InvalidMessageHMACException implements Exception {
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class InvalidMessageHMACException extends OmemoException implements Exception {
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String errMsg() => 'The computed HMAC does not match the provided HMAC';
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}
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/// Triggered by the Double Ratchet if skipping messages would cause skipping more than
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/// MAXSKIP messages
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class SkippingTooManyMessagesException implements Exception {
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class SkippingTooManyMessagesException extends OmemoException implements Exception {
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String errMsg() => 'Skipping messages would cause a skip bigger than MAXSKIP';
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}
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/// Triggered by the Session Manager if the message key is not encrypted for the device.
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class NotEncryptedForDeviceException implements Exception {
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class NotEncryptedForDeviceException extends OmemoException implements Exception {
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String errMsg() => 'Not encrypted for this device';
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}
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/// Triggered by the Session Manager when there is no key for decrypting the message.
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class NoDecryptionKeyException implements Exception {
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class NoDecryptionKeyException extends OmemoException implements Exception {
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String errMsg() => 'No key available for decrypting the message';
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}
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/// Triggered by the Session Manager when the identifier of the used Signed Prekey
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/// is neither the current SPK's identifier nor the old one's.
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class UnknownSignedPrekeyException implements Exception {
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class UnknownSignedPrekeyException extends OmemoException implements Exception {
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String errMsg() => 'Unknown Signed Prekey used.';
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}
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/// Triggered by the Session Manager when the received Key Exchange message does not meet
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/// the requirement that a key exchange, given that the ratchet already exists, must be
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/// sent after its creation.
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class InvalidKeyExchangeException implements Exception {
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class InvalidKeyExchangeException extends OmemoException implements Exception {
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String errMsg() => 'The key exchange was sent before the last kex finished';
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}
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/// Triggered by the Session Manager when a message's sequence number is smaller than we
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/// expect it to be.
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class MessageAlreadyDecryptedException implements Exception {
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class MessageAlreadyDecryptedException extends OmemoException implements Exception {
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String errMsg() => 'The message has already been decrypted';
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}
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9
lib/src/omemo/decryption_result.dart
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9
lib/src/omemo/decryption_result.dart
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@ -0,0 +1,9 @@
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import 'package:meta/meta.dart';
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import 'package:omemo_dart/src/errors.dart';
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@immutable
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class DecryptionResult {
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const DecryptionResult(this.payload, this.error);
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final String? payload;
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final OmemoException? error;
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}
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@ -9,7 +9,6 @@ import 'package:omemo_dart/src/x3dh/x3dh.dart';
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/// This class represents an OmemoBundle but with all keypairs belonging to the keys
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@immutable
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class Device {
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const Device(
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this.jid,
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this.id,
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@ -3,7 +3,6 @@ import 'package:omemo_dart/src/omemo/encrypted_key.dart';
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@immutable
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class EncryptionResult {
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const EncryptionResult(this.ciphertext, this.encryptedKeys);
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/// The actual message that was encrypted
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611
lib/src/omemo/omemomanager.dart
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611
lib/src/omemo/omemomanager.dart
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@ -0,0 +1,611 @@
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import 'dart:async';
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import 'dart:collection';
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import 'dart:convert';
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import 'package:collection/collection.dart';
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import 'package:cryptography/cryptography.dart';
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import 'package:logging/logging.dart';
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import 'package:meta/meta.dart';
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import 'package:omemo_dart/src/crypto.dart';
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import 'package:omemo_dart/src/double_ratchet/double_ratchet.dart';
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import 'package:omemo_dart/src/errors.dart';
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import 'package:omemo_dart/src/helpers.dart';
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import 'package:omemo_dart/src/keys.dart';
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import 'package:omemo_dart/src/omemo/bundle.dart';
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import 'package:omemo_dart/src/omemo/decryption_result.dart';
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import 'package:omemo_dart/src/omemo/device.dart';
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import 'package:omemo_dart/src/omemo/encrypted_key.dart';
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import 'package:omemo_dart/src/omemo/encryption_result.dart';
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import 'package:omemo_dart/src/omemo/events.dart';
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import 'package:omemo_dart/src/omemo/ratchet_map_key.dart';
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import 'package:omemo_dart/src/omemo/stanza.dart';
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import 'package:omemo_dart/src/protobuf/omemo_authenticated_message.dart';
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import 'package:omemo_dart/src/protobuf/omemo_key_exchange.dart';
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import 'package:omemo_dart/src/protobuf/omemo_message.dart';
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import 'package:omemo_dart/src/trust/base.dart';
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import 'package:omemo_dart/src/x3dh/x3dh.dart';
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import 'package:synchronized/synchronized.dart';
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/// The info used for when encrypting the AES key for the actual payload.
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const omemoPayloadInfoString = 'OMEMO Payload';
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class OmemoManager {
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OmemoManager(
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this._device,
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this._trustManager,
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this.sendEmptyOmemoMessage,
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this.fetchDeviceList,
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this.fetchDeviceBundle,
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);
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final Logger _log = Logger('OmemoManager');
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/// Functions for connecting with the OMEMO library
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final Future<void> Function(EncryptionResult result, String recipientJid) sendEmptyOmemoMessage;
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final Future<List<int>> Function(String jid) fetchDeviceList;
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final Future<OmemoBundle?> Function(String jid, int id) fetchDeviceBundle;
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/// Map bare JID to its known devices
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Map<String, List<int>> _deviceList = {};
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/// Map bare JIDs to whether we already requested the device list once
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final Map<String, bool> _deviceListRequested = {};
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/// Map bare a ratchet key to its ratchet. Note that this is also locked by
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/// _ratchetCriticalSectionLock.
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Map<RatchetMapKey, OmemoDoubleRatchet> _ratchetMap = {};
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/// For preventing a race condition in encryption/decryption
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final Map<String, Queue<Completer<void>>> _ratchetCriticalSectionQueue = {};
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final Lock _ratchetCriticalSectionLock = Lock();
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/// The OmemoManager's trust management
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final TrustManager _trustManager;
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TrustManager get trustManager => _trustManager;
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/// Our own keys...
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final Lock _deviceLock = Lock();
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// ignore: prefer_final_fields
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Device _device;
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/// The event bus of the session manager
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final StreamController<OmemoEvent> _eventStreamController = StreamController<OmemoEvent>.broadcast();
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/// Enter the critical section for performing cryptographic operations on the ratchets
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Future<void> _enterRatchetCriticalSection(String jid) async {
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final completer = await _ratchetCriticalSectionLock.synchronized(() {
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if (_ratchetCriticalSectionQueue.containsKey(jid)) {
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final c = Completer<void>();
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_ratchetCriticalSectionQueue[jid]!.addLast(c);
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return c;
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}
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_ratchetCriticalSectionQueue[jid] = Queue();
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return null;
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});
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if (completer != null) {
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await completer.future;
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}
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}
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/// Leave the critical section for the ratchets.
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Future<void> _leaveRatchetCriticalSection(String jid) async {
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await _ratchetCriticalSectionLock.synchronized(() {
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if (_ratchetCriticalSectionQueue.containsKey(jid)) {
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if (_ratchetCriticalSectionQueue[jid]!.isEmpty) {
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_ratchetCriticalSectionQueue.remove(jid);
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} else {
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_ratchetCriticalSectionQueue[jid]!.removeFirst().complete();
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}
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}
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});
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}
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Future<String?> _decryptAndVerifyHmac(List<int>? ciphertext, List<int> keyAndHmac) async {
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// Empty OMEMO messages should just have the key decrypted and/or session set up.
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if (ciphertext == null) {
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return null;
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}
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final key = keyAndHmac.sublist(0, 32);
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final hmac = keyAndHmac.sublist(32, 48);
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final derivedKeys = await deriveEncryptionKeys(key, omemoPayloadInfoString);
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final computedHmac = await truncatedHmac(ciphertext, derivedKeys.authenticationKey);
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if (!listsEqual(hmac, computedHmac)) {
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throw InvalidMessageHMACException();
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}
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return utf8.decode(
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await aes256CbcDecrypt(ciphertext, derivedKeys.encryptionKey, derivedKeys.iv),
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);
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}
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/// Add a session [ratchet] with the [deviceId] to the internal tracking state.
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/// NOTE: Must be called from within the ratchet critical section.
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void _addSession(String jid, int deviceId, OmemoDoubleRatchet ratchet) {
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// Add the bundle Id
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if (!_deviceList.containsKey(jid)) {
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_deviceList[jid] = [deviceId];
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// Commit the device map
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_eventStreamController.add(DeviceMapModifiedEvent(_deviceList));
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} else {
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// Prevent having the same device multiple times in the list
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if (!_deviceList[jid]!.contains(deviceId)) {
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_deviceList[jid]!.add(deviceId);
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// Commit the device map
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_eventStreamController.add(DeviceMapModifiedEvent(_deviceList));
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}
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}
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// Add the ratchet session
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final key = RatchetMapKey(jid, deviceId);
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_ratchetMap[key] = ratchet;
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// Commit the ratchet
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_eventStreamController.add(RatchetModifiedEvent(jid, deviceId, ratchet, true));
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}
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/// Build a new session with the user at [jid] with the device [deviceId] using data
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/// from the key exchange [kex]. In case [kex] contains an unknown Signed Prekey
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/// identifier an UnknownSignedPrekeyException will be thrown.
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Future<OmemoDoubleRatchet> _addSessionFromKeyExchange(String jid, int deviceId, OmemoKeyExchange kex) async {
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// Pick the correct SPK
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final device = await getDevice();
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OmemoKeyPair spk;
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if (kex.spkId == _device.spkId) {
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spk = _device.spk;
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} else if (kex.spkId == _device.oldSpkId) {
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spk = _device.oldSpk!;
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} else {
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throw UnknownSignedPrekeyException();
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}
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final kexResult = await x3dhFromInitialMessage(
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X3DHMessage(
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OmemoPublicKey.fromBytes(kex.ik!, KeyPairType.ed25519),
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OmemoPublicKey.fromBytes(kex.ek!, KeyPairType.x25519),
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kex.pkId!,
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),
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spk,
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device.opks.values.elementAt(kex.pkId!),
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device.ik,
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);
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final ratchet = await OmemoDoubleRatchet.acceptNewSession(
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spk,
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OmemoPublicKey.fromBytes(kex.ik!, KeyPairType.ed25519),
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kexResult.sk,
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kexResult.ad,
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getTimestamp(),
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);
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return ratchet;
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}
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/// Create a ratchet session initiated by Alice to the user with Jid [jid] and the device
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/// [deviceId] from the bundle [bundle].
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@visibleForTesting
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Future<OmemoKeyExchange> addSessionFromBundle(String jid, int deviceId, OmemoBundle bundle) async {
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final device = await getDevice();
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final kexResult = await x3dhFromBundle(
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bundle,
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device.ik,
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);
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final ratchet = await OmemoDoubleRatchet.initiateNewSession(
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bundle.spk,
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bundle.ik,
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kexResult.sk,
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kexResult.ad,
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getTimestamp(),
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);
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await _trustManager.onNewSession(jid, deviceId);
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_addSession(jid, deviceId, ratchet);
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return OmemoKeyExchange()
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..pkId = kexResult.opkId
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..spkId = bundle.spkId
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..ik = await device.ik.pk.getBytes()
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..ek = await kexResult.ek.pk.getBytes();
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}
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/// In case a decryption error occurs, the Double Ratchet spec says to just restore
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/// the ratchet to its old state. As such, this function restores the ratchet at
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/// [mapKey] with [oldRatchet].
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/// NOTE: Must be called from within the ratchet critical section
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void _restoreRatchet(RatchetMapKey mapKey, OmemoDoubleRatchet oldRatchet) {
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_log.finest('Restoring ratchet ${mapKey.jid}:${mapKey.deviceId} to ${oldRatchet.nr}');
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_ratchetMap[mapKey] = oldRatchet;
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// Commit the ratchet
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_eventStreamController.add(
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RatchetModifiedEvent(
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mapKey.jid,
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mapKey.deviceId,
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oldRatchet,
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false,
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),
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);
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}
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/// Attempt to decrypt [ciphertext]. [keys] refers to the <key /> elements inside the
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/// <keys /> element with a "jid" attribute matching our own. [senderJid] refers to the
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/// bare Jid of the sender. [senderDeviceId] refers to the "sid" attribute of the
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/// <encrypted /> element.
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/// [timestamp] refers to the time the message was sent. This might be either what the
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/// server tells you via "XEP-0203: Delayed Delivery" or the point in time at which
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/// you received the stanza, if no Delayed Delivery element was found.
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///
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/// If the received message is an empty OMEMO message, i.e. there is no <payload />
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/// element, then [ciphertext] must be set to null. In this case, this function
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/// will return null as there is no message to be decrypted. This, however, is used
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/// to set up sessions or advance the ratchets.
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Future<String?> decryptMessage(List<int>? ciphertext, String senderJid, int senderDeviceId, List<EncryptedKey> keys, int timestamp) async {
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// Try to find a session we can decrypt with.
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var device = await getDevice();
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final rawKey = keys.firstWhereOrNull((key) => key.rid == device.id);
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if (rawKey == null) {
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throw NotEncryptedForDeviceException();
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}
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final ratchetKey = RatchetMapKey(senderJid, senderDeviceId);
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final decodedRawKey = base64.decode(rawKey.value);
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List<int>? keyAndHmac;
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OmemoAuthenticatedMessage authMessage;
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OmemoDoubleRatchet? oldRatchet;
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OmemoMessage? message;
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if (rawKey.kex) {
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// If the ratchet already existed, we store it. If it didn't, oldRatchet will stay
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// null.
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final oldRatchet = _getRatchet(ratchetKey)?.clone();
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final kex = OmemoKeyExchange.fromBuffer(decodedRawKey);
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authMessage = kex.message!;
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message = OmemoMessage.fromBuffer(authMessage.message!);
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// Guard against old key exchanges
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if (oldRatchet != null) {
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_log.finest('KEX for existent ratchet. ${oldRatchet.pn}');
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if (oldRatchet.kexTimestamp > timestamp) {
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throw InvalidKeyExchangeException();
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}
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// Try to decrypt it
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try {
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final decrypted = await oldRatchet.ratchetDecrypt(message, authMessage.writeToBuffer());
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// Commit the ratchet
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_eventStreamController.add(
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RatchetModifiedEvent(
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senderJid,
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senderDeviceId,
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oldRatchet,
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false,
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),
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);
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final plaintext = await _decryptAndVerifyHmac(
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ciphertext,
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decrypted,
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);
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_addSession(senderJid, senderDeviceId, oldRatchet);
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return plaintext;
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} catch (_) {
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_log.finest('Failed to use old ratchet with KEX for existing ratchet');
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}
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}
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final r = await _addSessionFromKeyExchange(senderJid, senderDeviceId, kex);
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await _trustManager.onNewSession(senderJid, senderDeviceId);
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_addSession(senderJid, senderDeviceId, r);
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// Replace the OPK
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// TODO(PapaTutuWawa): Replace the OPK when we know that the KEX worked
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await _deviceLock.synchronized(() async {
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device = await device.replaceOnetimePrekey(kex.pkId!);
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// Commit the device
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_eventStreamController.add(DeviceModifiedEvent(device));
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});
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} else {
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authMessage = OmemoAuthenticatedMessage.fromBuffer(decodedRawKey);
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message = OmemoMessage.fromBuffer(authMessage.message!);
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}
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final devices = _deviceList[senderJid];
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if (devices == null) {
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throw NoDecryptionKeyException();
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}
|
||||
if (!devices.contains(senderDeviceId)) {
|
||||
throw NoDecryptionKeyException();
|
||||
}
|
||||
|
||||
// We can guarantee that the ratchet exists at this point in time
|
||||
final ratchet = _getRatchet(ratchetKey)!;
|
||||
oldRatchet ??= ratchet.clone();
|
||||
|
||||
try {
|
||||
if (rawKey.kex) {
|
||||
keyAndHmac = await ratchet.ratchetDecrypt(message, authMessage.writeToBuffer());
|
||||
} else {
|
||||
keyAndHmac = await ratchet.ratchetDecrypt(message, decodedRawKey);
|
||||
}
|
||||
} catch (_) {
|
||||
_restoreRatchet(ratchetKey, oldRatchet);
|
||||
rethrow;
|
||||
}
|
||||
|
||||
// Commit the ratchet
|
||||
_eventStreamController.add(
|
||||
RatchetModifiedEvent(
|
||||
senderJid,
|
||||
senderDeviceId,
|
||||
ratchet,
|
||||
false,
|
||||
),
|
||||
);
|
||||
|
||||
try {
|
||||
return _decryptAndVerifyHmac(ciphertext, keyAndHmac);
|
||||
} catch (_) {
|
||||
_restoreRatchet(ratchetKey, oldRatchet);
|
||||
rethrow;
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns, if it exists, the ratchet associated with [key].
|
||||
/// NOTE: Must be called from within the ratchet critical section.
|
||||
OmemoDoubleRatchet? _getRatchet(RatchetMapKey key) => _ratchetMap[key];
|
||||
|
||||
/// Figure out what bundles we have to still build a session with.
|
||||
Future<List<OmemoBundle>> _fetchNewBundles(String jid) async {
|
||||
// Check if we already requested the device list for [jid]
|
||||
List<int> bundlesToFetch;
|
||||
if (!_deviceListRequested.containsKey(jid) || !_deviceList.containsKey(jid)) {
|
||||
// We don't have an up-to-date version of the device list
|
||||
final newDeviceList = await fetchDeviceList(jid);
|
||||
_deviceList[jid] = newDeviceList;
|
||||
bundlesToFetch = newDeviceList
|
||||
.where((id) {
|
||||
return !_ratchetMap.containsKey(RatchetMapKey(jid, id)) ||
|
||||
_deviceList[jid]?.contains(id) == false;
|
||||
}).toList();
|
||||
} else {
|
||||
// We already have an up-to-date version of the device list
|
||||
bundlesToFetch = _deviceList[jid]!
|
||||
.where((id) => !_ratchetMap.containsKey(RatchetMapKey(jid, id)))
|
||||
.toList();
|
||||
}
|
||||
|
||||
final newBundles = List<OmemoBundle>.empty(growable: true);
|
||||
for (final id in bundlesToFetch) {
|
||||
final bundle = await fetchDeviceBundle(jid, id);
|
||||
if (bundle != null) newBundles.add(bundle);
|
||||
}
|
||||
|
||||
return newBundles;
|
||||
}
|
||||
|
||||
/// Encrypt the key [plaintext] for all known bundles of the Jids in [jids]. Returns a
|
||||
/// map that maps the device Id to the ciphertext of [plaintext].
|
||||
///
|
||||
/// If [plaintext] is null, then the result will be an empty OMEMO message, i.e. one that
|
||||
/// does not contain a <payload /> element. This means that the ciphertext attribute of
|
||||
/// the result will be null as well.
|
||||
/// NOTE: Must be called within the ratchet critical section
|
||||
Future<EncryptionResult> _encryptToJids(List<String> jids, String? plaintext) async {
|
||||
final encryptedKeys = List<EncryptedKey>.empty(growable: true);
|
||||
|
||||
var ciphertext = const <int>[];
|
||||
var keyPayload = const <int>[];
|
||||
if (plaintext != null) {
|
||||
// Generate the key and encrypt the plaintext
|
||||
final key = generateRandomBytes(32);
|
||||
final keys = await deriveEncryptionKeys(key, omemoPayloadInfoString);
|
||||
ciphertext = await aes256CbcEncrypt(
|
||||
utf8.encode(plaintext),
|
||||
keys.encryptionKey,
|
||||
keys.iv,
|
||||
);
|
||||
final hmac = await truncatedHmac(ciphertext, keys.authenticationKey);
|
||||
keyPayload = concat([key, hmac]);
|
||||
} else {
|
||||
keyPayload = List<int>.filled(32, 0x0);
|
||||
}
|
||||
|
||||
final kex = <int, OmemoKeyExchange>{};
|
||||
for (final jid in jids) {
|
||||
for (final newSession in await _fetchNewBundles(jid)) {
|
||||
kex[newSession.id] = await addSessionFromBundle(
|
||||
newSession.jid,
|
||||
newSession.id,
|
||||
newSession,
|
||||
);
|
||||
}
|
||||
}
|
||||
|
||||
// We assume that the user already checked if the session exists
|
||||
for (final jid in jids) {
|
||||
for (final deviceId in _deviceList[jid]!) {
|
||||
// Empty OMEMO messages are allowed to bypass trust
|
||||
if (plaintext != null) {
|
||||
// Only encrypt to devices that are trusted
|
||||
if (!(await _trustManager.isTrusted(jid, deviceId))) continue;
|
||||
|
||||
// Only encrypt to devices that are enabled
|
||||
if (!(await _trustManager.isEnabled(jid, deviceId))) continue;
|
||||
}
|
||||
|
||||
final ratchetKey = RatchetMapKey(jid, deviceId);
|
||||
var ratchet = _ratchetMap[ratchetKey]!;
|
||||
final ciphertext = (await ratchet.ratchetEncrypt(keyPayload)).ciphertext;
|
||||
|
||||
if (kex.isNotEmpty && kex.containsKey(deviceId)) {
|
||||
// The ratchet did not exist
|
||||
final k = kex[deviceId]!
|
||||
..message = OmemoAuthenticatedMessage.fromBuffer(ciphertext);
|
||||
final buffer = base64.encode(k.writeToBuffer());
|
||||
encryptedKeys.add(
|
||||
EncryptedKey(
|
||||
jid,
|
||||
deviceId,
|
||||
buffer,
|
||||
true,
|
||||
),
|
||||
);
|
||||
|
||||
ratchet = ratchet.cloneWithKex(buffer);
|
||||
_ratchetMap[ratchetKey] = ratchet;
|
||||
} else if (!ratchet.acknowledged) {
|
||||
// The ratchet exists but is not acked
|
||||
if (ratchet.kex != null) {
|
||||
final oldKex = OmemoKeyExchange.fromBuffer(base64.decode(ratchet.kex!))
|
||||
..message = OmemoAuthenticatedMessage.fromBuffer(ciphertext);
|
||||
|
||||
encryptedKeys.add(
|
||||
EncryptedKey(
|
||||
jid,
|
||||
deviceId,
|
||||
base64.encode(oldKex.writeToBuffer()),
|
||||
true,
|
||||
),
|
||||
);
|
||||
} else {
|
||||
// The ratchet is not acked but we don't have the old key exchange
|
||||
_log.warning('Ratchet for $jid:$deviceId is not acked but the kex attribute is null');
|
||||
encryptedKeys.add(
|
||||
EncryptedKey(
|
||||
jid,
|
||||
deviceId,
|
||||
base64.encode(ciphertext),
|
||||
false,
|
||||
),
|
||||
);
|
||||
}
|
||||
} else {
|
||||
// The ratchet exists and is acked
|
||||
encryptedKeys.add(
|
||||
EncryptedKey(
|
||||
jid,
|
||||
deviceId,
|
||||
base64.encode(ciphertext),
|
||||
false,
|
||||
),
|
||||
);
|
||||
}
|
||||
|
||||
// Commit the ratchet
|
||||
_eventStreamController.add(RatchetModifiedEvent(jid, deviceId, ratchet, false));
|
||||
}
|
||||
}
|
||||
|
||||
return EncryptionResult(
|
||||
plaintext != null ? ciphertext : null,
|
||||
encryptedKeys,
|
||||
);
|
||||
}
|
||||
|
||||
Future<DecryptionResult> onIncomingStanza(OmemoIncomingStanza stanza) async {
|
||||
await _enterRatchetCriticalSection(stanza.bareSenderJid);
|
||||
|
||||
final ratchetKey = RatchetMapKey(stanza.bareSenderJid, stanza.senderDeviceId);
|
||||
final ratchetCreated = !_ratchetMap.containsKey(ratchetKey);
|
||||
String? payload;
|
||||
try {
|
||||
payload = await decryptMessage(
|
||||
base64.decode(stanza.payload),
|
||||
stanza.bareSenderJid,
|
||||
stanza.senderDeviceId,
|
||||
stanza.keys,
|
||||
stanza.timestamp,
|
||||
);
|
||||
} on OmemoException catch (ex) {
|
||||
await _leaveRatchetCriticalSection(stanza.bareSenderJid);
|
||||
return DecryptionResult(
|
||||
null,
|
||||
ex,
|
||||
);
|
||||
}
|
||||
|
||||
// Check if the ratchet is acked
|
||||
final ratchet = _getRatchet(ratchetKey);
|
||||
assert(ratchet != null, 'We decrypted the message, so the ratchet must exist');
|
||||
|
||||
if (ratchet!.nr > 53) {
|
||||
await sendEmptyOmemoMessage(
|
||||
await _encryptToJids(
|
||||
[stanza.bareSenderJid],
|
||||
null,
|
||||
),
|
||||
stanza.bareSenderJid,
|
||||
);
|
||||
}
|
||||
|
||||
// Ratchet is acked
|
||||
if (!ratchetCreated && ratchet.acknowledged) {
|
||||
await _leaveRatchetCriticalSection(stanza.bareSenderJid);
|
||||
return DecryptionResult(
|
||||
payload,
|
||||
null,
|
||||
);
|
||||
}
|
||||
|
||||
// Ratchet is not acked. Mark as acked and send an empty OMEMO message.
|
||||
await ratchetAcknowledged(
|
||||
stanza.bareSenderJid,
|
||||
stanza.senderDeviceId,
|
||||
enterCriticalSection: false,
|
||||
);
|
||||
await sendEmptyOmemoMessage(
|
||||
await _encryptToJids(
|
||||
[stanza.bareSenderJid],
|
||||
null,
|
||||
),
|
||||
stanza.bareSenderJid,
|
||||
);
|
||||
|
||||
await _leaveRatchetCriticalSection(stanza.bareSenderJid);
|
||||
return DecryptionResult(
|
||||
payload,
|
||||
null,
|
||||
);
|
||||
}
|
||||
|
||||
Future<EncryptionResult?> onOutgoingStanza(OmemoOutgoingStanza stanza) async {
|
||||
return _encryptToJids(
|
||||
stanza.recipientJids,
|
||||
stanza.payload,
|
||||
);
|
||||
}
|
||||
|
||||
/// Mark the ratchet for device [deviceId] from [jid] as acked.
|
||||
Future<void> ratchetAcknowledged(String jid, int deviceId, { bool enterCriticalSection = true }) async {
|
||||
if (enterCriticalSection) await _enterRatchetCriticalSection(jid);
|
||||
|
||||
final ratchet = _ratchetMap[RatchetMapKey(jid, deviceId)]!
|
||||
..acknowledged = true;
|
||||
|
||||
// Commit it
|
||||
_eventStreamController.add(RatchetModifiedEvent(jid, deviceId, ratchet, false));
|
||||
|
||||
if (enterCriticalSection) await _leaveRatchetCriticalSection(jid);
|
||||
}
|
||||
|
||||
Future<Device> getDevice() => _deviceLock.synchronized(() => _device);
|
||||
|
||||
/// Ensures that the device list is fetched again on the next message sending.
|
||||
void onNewConnection() {
|
||||
_deviceListRequested.clear();
|
||||
}
|
||||
|
||||
/// Sets the device list for [jid] to [devices].
|
||||
void onDeviceListUpdate(String jid, List<int> devices) {
|
||||
_deviceList[jid] = devices;
|
||||
_deviceListRequested[jid] = true;
|
||||
}
|
||||
|
||||
List<int>? getDeviceListForJid(String jid) => _deviceList[jid];
|
||||
|
||||
void initialize(Map<RatchetMapKey, OmemoDoubleRatchet> ratchetMap, Map<String, List<int>> deviceList) {
|
||||
_deviceList = deviceList;
|
||||
_ratchetMap = ratchetMap;
|
||||
}
|
||||
}
|
25
lib/src/omemo/stanza.dart
Normal file
25
lib/src/omemo/stanza.dart
Normal file
@ -0,0 +1,25 @@
|
||||
import 'package:omemo_dart/src/omemo/encrypted_key.dart';
|
||||
|
||||
class OmemoIncomingStanza {
|
||||
const OmemoIncomingStanza(
|
||||
this.bareSenderJid,
|
||||
this.senderDeviceId,
|
||||
this.timestamp,
|
||||
this.keys,
|
||||
this.payload,
|
||||
);
|
||||
final String bareSenderJid;
|
||||
final int senderDeviceId;
|
||||
final int timestamp;
|
||||
final List<EncryptedKey> keys;
|
||||
final String payload;
|
||||
}
|
||||
|
||||
class OmemoOutgoingStanza {
|
||||
const OmemoOutgoingStanza(
|
||||
this.recipientJids,
|
||||
this.payload,
|
||||
);
|
||||
final List<String> recipientJids;
|
||||
final String payload;
|
||||
}
|
@ -3,7 +3,6 @@ import 'package:omemo_dart/src/protobuf/omemo_authenticated_message.dart';
|
||||
import 'package:omemo_dart/src/protobuf/protobuf.dart';
|
||||
|
||||
class OmemoKeyExchange {
|
||||
|
||||
OmemoKeyExchange();
|
||||
|
||||
factory OmemoKeyExchange.fromBuffer(List<int> data) {
|
||||
|
220
test/omemomanager_test.dart
Normal file
220
test/omemomanager_test.dart
Normal file
@ -0,0 +1,220 @@
|
||||
import 'dart:convert';
|
||||
import 'package:logging/logging.dart';
|
||||
import 'package:omemo_dart/omemo_dart.dart';
|
||||
import 'package:omemo_dart/src/omemo/omemomanager.dart' as omemo;
|
||||
import 'package:omemo_dart/src/trust/always.dart';
|
||||
import 'package:test/test.dart';
|
||||
|
||||
void main() {
|
||||
Logger.root
|
||||
..level = Level.ALL
|
||||
..onRecord.listen((record) {
|
||||
// ignore: avoid_print
|
||||
print('${record.level.name}: ${record.message}');
|
||||
});
|
||||
|
||||
test('Test sending a message without the device list cache', () async {
|
||||
const aliceJid = 'alice@server1';
|
||||
const bobJid = 'bob@server2';
|
||||
var aliceEmptyMessageSent = 0;
|
||||
var bobEmptyMessageSent = 0;
|
||||
|
||||
final aliceDevice = await Device.generateNewDevice(aliceJid, opkAmount: 1);
|
||||
final bobDevice = await Device.generateNewDevice(bobJid, opkAmount: 1);
|
||||
|
||||
final aliceManager = omemo.OmemoManager(
|
||||
aliceDevice,
|
||||
AlwaysTrustingTrustManager(),
|
||||
(result, recipientJid) async {
|
||||
aliceEmptyMessageSent++;
|
||||
},
|
||||
(jid) async {
|
||||
expect(jid, bobJid);
|
||||
return [ bobDevice.id ];
|
||||
},
|
||||
(jid, id) async {
|
||||
expect(jid, bobJid);
|
||||
return bobDevice.toBundle();
|
||||
},
|
||||
);
|
||||
final bobManager = omemo.OmemoManager(
|
||||
bobDevice,
|
||||
AlwaysTrustingTrustManager(),
|
||||
(result, recipientJid) async {
|
||||
bobEmptyMessageSent++;
|
||||
},
|
||||
(jid) async {
|
||||
expect(jid, aliceJid);
|
||||
return [aliceDevice.id];
|
||||
},
|
||||
(jid, id) async {
|
||||
expect(jid, aliceJid);
|
||||
return aliceDevice.toBundle();
|
||||
},
|
||||
);
|
||||
|
||||
// Alice sends a message
|
||||
final aliceResult = await aliceManager.onOutgoingStanza(
|
||||
const OmemoOutgoingStanza(
|
||||
[bobJid],
|
||||
'Hello world',
|
||||
),
|
||||
);
|
||||
|
||||
// Bob must be able to decrypt the message
|
||||
final bobResult = await bobManager.onIncomingStanza(
|
||||
OmemoIncomingStanza(
|
||||
aliceJid,
|
||||
aliceDevice.id,
|
||||
DateTime.now().millisecondsSinceEpoch,
|
||||
aliceResult!.encryptedKeys,
|
||||
base64.encode(aliceResult.ciphertext!),
|
||||
),
|
||||
);
|
||||
|
||||
expect(aliceEmptyMessageSent, 0);
|
||||
expect(bobEmptyMessageSent, 1);
|
||||
expect(bobResult.payload, 'Hello world');
|
||||
|
||||
// Alice receives the ack message
|
||||
await aliceManager.ratchetAcknowledged(
|
||||
bobJid,
|
||||
bobDevice.id,
|
||||
);
|
||||
|
||||
// Bob now responds
|
||||
final bobResult2 = await bobManager.onOutgoingStanza(
|
||||
const OmemoOutgoingStanza(
|
||||
[aliceJid],
|
||||
'Hello world, Alice',
|
||||
),
|
||||
);
|
||||
final aliceResult2 = await aliceManager.onIncomingStanza(
|
||||
OmemoIncomingStanza(
|
||||
bobJid,
|
||||
bobDevice.id,
|
||||
DateTime.now().millisecondsSinceEpoch,
|
||||
bobResult2!.encryptedKeys,
|
||||
base64.encode(bobResult2.ciphertext!),
|
||||
),
|
||||
);
|
||||
|
||||
expect(aliceResult2.error, null);
|
||||
expect(aliceEmptyMessageSent, 0);
|
||||
expect(bobEmptyMessageSent, 1);
|
||||
expect(aliceResult2.payload, 'Hello world, Alice');
|
||||
});
|
||||
|
||||
test('Test triggering the heartbeat', () async {
|
||||
const aliceJid = 'alice@server1';
|
||||
const bobJid = 'bob@server2';
|
||||
var aliceEmptyMessageSent = 0;
|
||||
var bobEmptyMessageSent = 0;
|
||||
|
||||
final aliceDevice = await Device.generateNewDevice(aliceJid, opkAmount: 1);
|
||||
final bobDevice = await Device.generateNewDevice(bobJid, opkAmount: 1);
|
||||
|
||||
final aliceManager = omemo.OmemoManager(
|
||||
aliceDevice,
|
||||
AlwaysTrustingTrustManager(),
|
||||
(result, recipientJid) async {
|
||||
aliceEmptyMessageSent++;
|
||||
},
|
||||
(jid) async {
|
||||
expect(jid, bobJid);
|
||||
return [ bobDevice.id ];
|
||||
},
|
||||
(jid, id) async {
|
||||
expect(jid, bobJid);
|
||||
return bobDevice.toBundle();
|
||||
},
|
||||
);
|
||||
final bobManager = omemo.OmemoManager(
|
||||
bobDevice,
|
||||
AlwaysTrustingTrustManager(),
|
||||
(result, recipientJid) async {
|
||||
bobEmptyMessageSent++;
|
||||
},
|
||||
(jid) async {
|
||||
expect(jid, aliceJid);
|
||||
return [aliceDevice.id];
|
||||
},
|
||||
(jid, id) async {
|
||||
expect(jid, aliceJid);
|
||||
return aliceDevice.toBundle();
|
||||
},
|
||||
);
|
||||
|
||||
// Alice sends a message
|
||||
final aliceResult = await aliceManager.onOutgoingStanza(
|
||||
const OmemoOutgoingStanza(
|
||||
[bobJid],
|
||||
'Hello world',
|
||||
),
|
||||
);
|
||||
|
||||
// Bob must be able to decrypt the message
|
||||
final bobResult = await bobManager.onIncomingStanza(
|
||||
OmemoIncomingStanza(
|
||||
aliceJid,
|
||||
aliceDevice.id,
|
||||
DateTime.now().millisecondsSinceEpoch,
|
||||
aliceResult!.encryptedKeys,
|
||||
base64.encode(aliceResult.ciphertext!),
|
||||
),
|
||||
);
|
||||
|
||||
expect(aliceEmptyMessageSent, 0);
|
||||
expect(bobEmptyMessageSent, 1);
|
||||
expect(bobResult.payload, 'Hello world');
|
||||
|
||||
// Bob acknowledges the message
|
||||
await aliceManager.ratchetAcknowledged(bobJid, bobDevice.id);
|
||||
|
||||
// Alice now sends 52 messages that Bob decrypts
|
||||
for (var i = 0; i <= 51; i++) {
|
||||
final aliceResultLoop = await aliceManager.onOutgoingStanza(
|
||||
OmemoOutgoingStanza(
|
||||
[bobJid],
|
||||
'Test message $i',
|
||||
),
|
||||
);
|
||||
|
||||
final bobResultLoop = await bobManager.onIncomingStanza(
|
||||
OmemoIncomingStanza(
|
||||
aliceJid,
|
||||
aliceDevice.id,
|
||||
DateTime.now().millisecondsSinceEpoch,
|
||||
aliceResultLoop!.encryptedKeys,
|
||||
base64.encode(aliceResultLoop.ciphertext!),
|
||||
),
|
||||
);
|
||||
|
||||
expect(aliceEmptyMessageSent, 0);
|
||||
expect(bobEmptyMessageSent, 1);
|
||||
expect(bobResultLoop.payload, 'Test message $i');
|
||||
}
|
||||
|
||||
// Alice sends a final message that triggers a heartbeat
|
||||
final aliceResultFinal = await aliceManager.onOutgoingStanza(
|
||||
const OmemoOutgoingStanza(
|
||||
[bobJid],
|
||||
'Test message last',
|
||||
),
|
||||
);
|
||||
|
||||
final bobResultFinal = await bobManager.onIncomingStanza(
|
||||
OmemoIncomingStanza(
|
||||
aliceJid,
|
||||
aliceDevice.id,
|
||||
DateTime.now().millisecondsSinceEpoch,
|
||||
aliceResultFinal!.encryptedKeys,
|
||||
base64.encode(aliceResultFinal.ciphertext!),
|
||||
),
|
||||
);
|
||||
|
||||
expect(aliceEmptyMessageSent, 0);
|
||||
expect(bobEmptyMessageSent, 2);
|
||||
expect(bobResultFinal.payload, 'Test message last');
|
||||
});
|
||||
}
|
Loading…
Reference in New Issue
Block a user