signal-desktop/ts/services/profiles.ts

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// Copyright 2022 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
import type {
ClientZkProfileOperations,
ProfileKeyCredentialRequestContext,
} from '@signalapp/libsignal-client/zkgroup';
import PQueue from 'p-queue';
import type { ReadonlyDeep } from 'type-fest';
import type { ConversationModel } from '../models/conversations';
import type { CapabilitiesType, ProfileType } from '../textsecure/WebAPI';
import MessageSender from '../textsecure/SendMessage';
import type { ServiceIdString } from '../types/ServiceId';
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import { DataWriter } from '../sql/Client';
import * as log from '../logging/log';
import * as Errors from '../types/errors';
import * as Bytes from '../Bytes';
import { explodePromise } from '../util/explodePromise';
import { isRecord } from '../util/isRecord';
import { sleep } from '../util/sleep';
import { MINUTE, SECOND } from '../util/durations';
import {
generateProfileKeyCredentialRequest,
getClientZkProfileOperations,
handleProfileKeyCredential,
} from '../util/zkgroup';
import { isMe } from '../util/whatTypeOfConversation';
import { getUserLanguages } from '../util/userLanguages';
import { parseBadgesFromServer } from '../badges/parseBadgesFromServer';
import { strictAssert } from '../util/assert';
import { drop } from '../util/drop';
import { findRetryAfterTimeFromError } from '../jobs/helpers/findRetryAfterTimeFromError';
import { singleProtoJobQueue } from '../jobs/singleProtoJobQueue';
import { SEALED_SENDER } from '../types/SealedSender';
import { HTTPError } from '../textsecure/Errors';
import { Address } from '../types/Address';
import { QualifiedAddress } from '../types/QualifiedAddress';
import { trimForDisplay, verifyAccessKey, decryptProfile } from '../Crypto';
import type { ConversationLastProfileType } from '../model-types';
import type { GroupSendToken } from '../types/GroupSendEndorsements';
import {
maybeCreateGroupSendEndorsementState,
onFailedToSendWithEndorsements,
} from '../util/groupSendEndorsements';
type JobType = {
resolve: () => void;
reject: (error: Error) => void;
promise: Promise<void>;
startTime: number;
};
// Goals for this service:
// 1. Ensure that when we get a 413/429 from the server, we stop firing off profile
// fetches for a while.
// 2. Ensure that all existing profile fetches don't hang in this case; to solve this we
// cancel all outstanding requests when we hit a 413/429, and throw instead of
// queueing something new if we're waiting due to a retry-after. Note: It's no worse
// than what we were doing before, failing all requests and pushing the retry-after
// time out further.
// 3. Require no changes to callers.
// Potential future goals for this problem area:
// - Update all getProfiles() callers; make them resilient to longer delays
// - Keep track of last profile fetch per conversation, reduce unnecessary re-fetches
// - Enforce a maximum profile fetch frequency
// - Don't even attempt jobs when offline
const OBSERVED_CAPABILITY_KEYS = Object.keys({
deleteSync: true,
versionedExpirationTimer: true,
} satisfies CapabilitiesType) as ReadonlyArray<keyof CapabilitiesType>;
export class ProfileService {
private jobQueue: PQueue;
private jobsByConversationId: Map<string, JobType> = new Map();
private isPaused = false;
constructor(private fetchProfile = doGetProfile) {
this.jobQueue = new PQueue({ concurrency: 3, timeout: MINUTE * 2 });
this.jobsByConversationId = new Map();
log.info('Profile Service initialized');
}
public async get(
conversationId: string,
groupId: string | null
): Promise<void> {
const preCheckConversation =
window.ConversationController.get(conversationId);
if (!preCheckConversation) {
throw new Error(
`ProfileServices.get: Pre-check conversation ${conversationId} not found`
);
}
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if (window.ConversationController.isSignalConversationId(conversationId)) {
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return;
}
if (this.isPaused) {
throw new Error(
`ProfileService.get: Cannot add job to paused queue for conversation ${preCheckConversation.idForLogging()}`
);
}
const existing = this.jobsByConversationId.get(conversationId);
if (existing) {
return existing.promise;
}
const { resolve, reject, promise } = explodePromise<void>();
const jobData = {
promise,
resolve,
reject,
startTime: Date.now(),
};
const job = async () => {
const conversation = window.ConversationController.get(conversationId);
if (!conversation) {
throw new Error(
`ProfileServices.get: Conversation ${conversationId} not found`
);
}
try {
await this.fetchProfile(conversation, groupId);
resolve();
} catch (error) {
reject(error);
if (this.isPaused) {
return;
}
if (isRecord(error) && 'code' in error) {
if (error.code === -1) {
this.clearAll('Failed to connect to the server');
} else if (error.code === 413 || error.code === 429) {
this.clearAll(`got ${error.code} from server`);
const time = findRetryAfterTimeFromError(error);
void this.pause(time);
}
}
} finally {
this.jobsByConversationId.delete(conversationId);
const now = Date.now();
const delta = now - jobData.startTime;
if (delta > 30 * SECOND) {
log.warn(
`ProfileServices.get: Job for ${conversation.idForLogging()} finished ${delta}ms after queue`
);
}
const remainingItems = this.jobQueue.size;
if (remainingItems && remainingItems % 10 === 0) {
log.info(
`ProfileServices.get: ${remainingItems} jobs remaining in the queue`
);
}
}
};
this.jobsByConversationId.set(conversationId, jobData);
drop(this.jobQueue.add(job));
return promise;
}
public clearAll(reason: string): void {
if (this.isPaused) {
log.warn(
`ProfileService.clearAll: Already paused; not clearing; reason: '${reason}'`
);
return;
}
log.info(`ProfileService.clearAll: Clearing; reason: '${reason}'`);
try {
this.isPaused = true;
this.jobQueue.pause();
this.jobsByConversationId.forEach(job => {
job.reject(
new Error(
`ProfileService.clearAll: job cancelled because '${reason}'`
)
);
});
this.jobsByConversationId.clear();
this.jobQueue.clear();
this.jobQueue.start();
} finally {
this.isPaused = false;
log.info('ProfileService.clearAll: Done clearing');
}
}
public async pause(timeInMS: number): Promise<void> {
if (this.isPaused) {
log.warn('ProfileService.pause: Already paused, not pausing again.');
return;
}
log.info(`ProfileService.pause: Pausing queue for ${timeInMS}ms`);
this.isPaused = true;
this.jobQueue.pause();
try {
await sleep(timeInMS);
} finally {
log.info('ProfileService.pause: Restarting queue');
this.jobQueue.start();
this.isPaused = false;
}
}
}
export const profileService = new ProfileService();
// eslint-disable-next-line @typescript-eslint/no-namespace
namespace ProfileFetchOptions {
type Base = ReadonlyDeep<{
request: {
userLanguages: ReadonlyArray<string>;
};
}>;
type WithVersioned = ReadonlyDeep<{
profileKey: string;
profileCredentialRequestContext: ProfileKeyCredentialRequestContext | null;
request: {
profileKeyVersion: string;
profileKeyCredentialRequest: string | null;
};
}>;
type WithUnversioned = ReadonlyDeep<{
profileKey: null;
profileCredentialRequestContext: null;
request: {
profileKeyVersion: null;
profileKeyCredentialRequest: null;
};
}>;
type WithUnauthAccessKey = ReadonlyDeep<{
request: { accessKey: string; groupSendToken: null };
}>;
type WithUnauthGroupSendToken = ReadonlyDeep<{
request: {
accessKey: null;
groupSendToken: GroupSendToken;
};
}>;
type WithAuth = ReadonlyDeep<{
request: {
accessKey: null;
groupSendToken: null;
};
}>;
export type Unauth =
// versioned (unauth)
| (Base & WithVersioned & WithUnauthAccessKey)
// unversioned (unauth)
| (Base & WithUnversioned & WithUnauthAccessKey)
| (Base & WithUnversioned & WithUnauthGroupSendToken);
export type Auth =
// unversioned (auth) -- Using lastProfile
| (Base & WithVersioned & WithAuth)
// unversioned (auth)
| (Base & WithUnversioned & WithAuth);
}
export type ProfileFetchUnauthRequestOptions =
ProfileFetchOptions.Unauth['request'];
export type ProfileFetchAuthRequestOptions =
ProfileFetchOptions.Auth['request'];
async function buildProfileFetchOptions({
conversation,
lastProfile,
clientZkProfileCipher,
groupId,
}: {
conversation: ConversationModel;
lastProfile: ConversationLastProfileType | null;
clientZkProfileCipher: ClientZkProfileOperations;
groupId: string | null;
}): Promise<ProfileFetchOptions.Auth | ProfileFetchOptions.Unauth> {
const logId = `buildGetProfileOptions(${conversation.idForLogging()})`;
const userLanguages = getUserLanguages(
window.SignalContext.getPreferredSystemLocales(),
window.SignalContext.getResolvedMessagesLocale()
);
const profileKey = conversation.get('profileKey');
const profileKeyVersion = conversation.deriveProfileKeyVersion();
const accessKey = conversation.get('accessKey');
const serviceId = conversation.getCheckedServiceId('getProfile');
if (profileKey) {
strictAssert(
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profileKeyVersion != null && accessKey != null,
`${logId}: profileKeyVersion and accessKey are derived from profileKey`
);
if (!conversation.hasProfileKeyCredentialExpired()) {
log.info(`${logId}: using unexpired profile key credential`);
return {
profileKey,
profileCredentialRequestContext: null,
request: {
userLanguages,
accessKey,
groupSendToken: null,
profileKeyVersion,
profileKeyCredentialRequest: null,
},
};
}
log.info(`${logId}: generating profile key credential request`);
const result = generateProfileKeyCredentialRequest(
clientZkProfileCipher,
serviceId,
profileKey
);
return {
profileKey,
profileCredentialRequestContext: result.context,
request: {
userLanguages,
accessKey,
groupSendToken: null,
profileKeyVersion,
profileKeyCredentialRequest: result.requestHex,
},
};
}
strictAssert(
accessKey == null,
`${logId}: accessKey have to be absent because there is no profileKey`
);
// If we have a `lastProfile`, try getting the versioned profile with auth.
// Note: We can't try the group send token here because the versioned profile
// can't be decrypted without an up to date profile key.
if (
lastProfile != null &&
lastProfile.profileKey != null &&
lastProfile.profileKeyVersion != null
) {
log.info(`${logId}: using last profile key and version`);
return {
profileKey: lastProfile.profileKey,
profileCredentialRequestContext: null,
request: {
userLanguages,
accessKey: null,
groupSendToken: null,
profileKeyVersion: lastProfile.profileKeyVersion,
profileKeyCredentialRequest: null,
},
};
}
// Fallback to group send tokens for unversioned profiles
if (groupId != null) {
log.info(`${logId}: fetching group endorsements`);
let result = await maybeCreateGroupSendEndorsementState(groupId, false);
if (result.state == null && result.didRefreshGroupState) {
result = await maybeCreateGroupSendEndorsementState(groupId, true);
}
const groupSendEndorsementState = result.state;
const groupSendToken = groupSendEndorsementState?.buildToken(
new Set([serviceId])
);
if (groupSendToken != null) {
log.info(`${logId}: using group send token`);
return {
profileKey: null,
profileCredentialRequestContext: null,
request: {
userLanguages,
accessKey: null,
groupSendToken,
profileKeyVersion: null,
profileKeyCredentialRequest: null,
},
};
}
}
// Fallback to auth
return {
profileKey: null,
profileCredentialRequestContext: null,
request: {
userLanguages,
accessKey: null,
groupSendToken: null,
profileKeyVersion: null,
profileKeyCredentialRequest: null,
},
};
}
function decryptField(field: string, decryptionKey: Uint8Array): Uint8Array {
return decryptProfile(Bytes.fromBase64(field), decryptionKey);
}
function formatTextField(decrypted: Uint8Array): string {
return Bytes.toString(trimForDisplay(decrypted));
}
function isFieldDefined(field: string | null | undefined): field is string {
return field != null && field.length > 0;
}
function getFetchOptionsLabel(
options: ProfileFetchOptions.Auth | ProfileFetchOptions.Unauth
) {
let versioned: string;
if (options.request.profileKeyVersion != null) {
versioned = 'versioned';
} else {
versioned = 'unversioned';
}
let auth: string;
if (options.request.accessKey != null) {
auth = 'unauth: accessKey';
} else if (options.request.groupSendToken != null) {
auth = 'unauth: groupSendToken';
} else {
auth = 'auth';
}
return `${versioned}, ${auth}`;
}
async function doGetProfile(
c: ConversationModel,
groupId: string | null
): Promise<void> {
const logId = groupId
? `getProfile(${c.idForLogging()} in groupv2(${groupId}))`
: `getProfile(${c.idForLogging()})`;
const { messaging } = window.textsecure;
strictAssert(
messaging,
`${logId}: window.textsecure.messaging not available`
);
const { updatesUrl } = window.SignalContext.config;
strictAssert(
typeof updatesUrl === 'string',
`${logId}: expected updatesUrl to be a defined string`
);
const clientZkProfileCipher = getClientZkProfileOperations(
window.getServerPublicParams()
);
// Step #: Make sure we have an access key if we have a profile key.
c.deriveAccessKeyIfNeeded();
const serviceId = c.getCheckedServiceId('getProfile');
// Step #: Grab the profile key and version we last were successful decrypting with
// `lastProfile` is saved at the end of `doGetProfile` after successfully decrypting.
// `lastProfile` is used in case the `profileKey` was cleared because of a 401/403.
// `lastProfile` is cleared when we get a 404 fetching a profile.
const lastProfile = c.get('lastProfile');
// Step #: Build the request options we will use for fetching and decrypting the profile
const options = await buildProfileFetchOptions({
conversation: c,
lastProfile: lastProfile ?? null,
clientZkProfileCipher,
groupId,
});
const { request } = options;
const isVersioned = request.profileKeyVersion != null;
log.info(`${logId}: Fetching profile (${getFetchOptionsLabel(options)})`);
// Step #: Fetch profile
let profile: ProfileType;
try {
if (request.accessKey != null || request.groupSendToken != null) {
profile = await messaging.server.getProfileUnauth(serviceId, request);
} else {
profile = await messaging.server.getProfile(serviceId, request);
}
} catch (error) {
log.error(`${logId}: Failed to fetch profile`, Errors.toLogFormat(error));
if (error instanceof HTTPError) {
// Unauthorized/Forbidden
if (error.code === 401 || error.code === 403) {
if (request.groupSendToken != null) {
onFailedToSendWithEndorsements(error);
}
// Step #: Retries for unauthorized access keys and group send tokens
if (!isMe(c.attributes)) {
// Fallback from failed unauth (access key) request
if (request.accessKey != null) {
log.warn(
`${logId}: Got ${error.code} when using access key, removing profileKey and retrying`
);
await c.setProfileKey(undefined, {
reason: 'doGetProfile/accessKey/401+403',
});
// Retry fetch using last known profileKeyVersion or fetch
// unversioned profile.
return doGetProfile(c, groupId);
}
// Fallback from failed unauth (group send token) request
if (request.groupSendToken != null) {
log.warn(`${logId}: Got ${error.code} when using group send token`);
return doGetProfile(c, null);
}
}
// Step #: Record if the accessKey we have in the conversation is valid
const sealedSender = c.get('sealedSender');
if (
sealedSender === SEALED_SENDER.ENABLED ||
sealedSender === SEALED_SENDER.UNRESTRICTED
) {
if (!isMe(c.attributes)) {
log.warn(
`${logId}: Got ${error.code} when using accessKey, removing profileKey`
);
await c.setProfileKey(undefined, {
reason: 'doGetProfile/accessKey/401+403',
});
}
} else if (sealedSender === SEALED_SENDER.UNKNOWN) {
log.warn(
`${logId}: Got ${error.code} fetching profile, setting sealedSender = DISABLED`
);
c.set('sealedSender', SEALED_SENDER.DISABLED);
}
// TODO: Is it safe to ignore these errors?
return;
}
// Not Found
if (error.code === 404) {
log.info(`${logId}: Profile not found`);
c.set('profileLastFetchedAt', Date.now());
// Note: Writes to DB:
await c.removeLastProfile(lastProfile);
if (!isVersioned) {
log.info(`${logId}: Marking conversation unregistered`);
c.setUnregistered();
}
}
}
// throw all unhandled errors
throw error;
}
// Step #: Save `identityKey` to SignalProtocolStore
if (isFieldDefined(profile.identityKey)) {
const identityKeyBytes = Bytes.fromBase64(profile.identityKey);
// Note: Queues some jobs
await updateIdentityKey(identityKeyBytes, serviceId);
}
// Step #: Updating `sealedSender` based on the successful response
{
// Use the most up to date `accessKey` to prevent race conditions.
// Since we run asynchronous requests above - it is possible that someone
// updates or erases the profile key from under us.
const accessKey = c.get('accessKey');
let sealedSender: SEALED_SENDER;
if (isFieldDefined(profile.unidentifiedAccess)) {
if (isFieldDefined(profile.unrestrictedUnidentifiedAccess)) {
sealedSender = SEALED_SENDER.UNRESTRICTED;
} else if (accessKey != null) {
const haveCorrectKey = verifyAccessKey(
Bytes.fromBase64(accessKey),
Bytes.fromBase64(profile.unidentifiedAccess)
);
if (haveCorrectKey) {
sealedSender = SEALED_SENDER.ENABLED;
} else {
log.info(
`${logId}: Access key mismatch with profile.unidentifiedAccess`
);
}
}
}
// Default to disabled if we don't have unrestricted access or the correct access key
sealedSender ??= SEALED_SENDER.DISABLED;
log.info(
`${logId}: setting sealedSender to ${SEALED_SENDER[sealedSender]} ` +
`(unidentifiedAccess: ${isFieldDefined(profile.unidentifiedAccess)}, ` +
`unrestrictedUnidentifiedAccess: ${isFieldDefined(profile.unrestrictedUnidentifiedAccess)}, ` +
`accessKey: ${accessKey != null})`
);
c.set({ sealedSender });
}
// Step #: Grab the current `profileKey` (which may have updated) or the last
// profile key we successfully decrypted from.
const rawRequestDecryptionKey = options.profileKey ?? lastProfile?.profileKey;
const rawUpdatedDecryptionKey =
c.get('profileKey') ?? lastProfile?.profileKey;
const requestDecryptionKey = rawRequestDecryptionKey
? Bytes.fromBase64(rawRequestDecryptionKey)
: null;
const updatedDecryptionKey = rawUpdatedDecryptionKey
? Bytes.fromBase64(rawUpdatedDecryptionKey)
: null;
// Step #: Save profile `about` to conversation
if (isFieldDefined(profile.about)) {
if (updatedDecryptionKey != null) {
const decrypted = decryptField(profile.about, updatedDecryptionKey);
c.set('about', formatTextField(decrypted));
}
} else {
c.unset('about');
}
// Step #: Save profile `aboutEmoji` to conversation
if (isFieldDefined(profile.aboutEmoji)) {
if (updatedDecryptionKey != null) {
const decrypted = decryptField(profile.aboutEmoji, updatedDecryptionKey);
c.set('aboutEmoji', formatTextField(decrypted));
}
} else {
c.unset('aboutEmoji');
}
// Step #: Save profile `phoneNumberSharing` to conversation
if (isFieldDefined(profile.phoneNumberSharing)) {
if (updatedDecryptionKey != null) {
const decrypted = decryptField(
profile.phoneNumberSharing,
updatedDecryptionKey
);
// It should be one byte, but be conservative about it and
// set `sharingPhoneNumber` to `false` in all cases except [0x01].
const sharingPhoneNumber = decrypted.length === 1 && decrypted[0] === 1;
c.set('sharingPhoneNumber', sharingPhoneNumber);
}
} else {
c.unset('sharingPhoneNumber');
}
// Step #: Save our own `paymentAddress` to Storage
if (isFieldDefined(profile.paymentAddress) && isMe(c.attributes)) {
await window.storage.put('paymentAddress', profile.paymentAddress);
}
// Step #: Save profile `capabilities` to conversation
const pastCapabilities = c.get('capabilities');
if (profile.capabilities != null) {
c.set({ capabilities: profile.capabilities });
} else {
c.unset('capabilities');
}
// Step #: Save our own `observedCapabilities` to Storage and trigger sync if changed
if (isMe(c.attributes)) {
const newCapabilities = c.get('capabilities');
let hasChanged = false;
const observedCapabilities = {
...window.storage.get('observedCapabilities'),
};
const newKeys = new Array<string>();
for (const key of OBSERVED_CAPABILITY_KEYS) {
// Already reported
if (observedCapabilities[key]) {
continue;
}
if (newCapabilities?.[key]) {
if (!pastCapabilities?.[key]) {
hasChanged = true;
newKeys.push(key);
}
observedCapabilities[key] = true;
}
}
await window.storage.put('observedCapabilities', observedCapabilities);
if (hasChanged) {
log.info(
'getProfile: detected a capability flip, sending fetch profile',
newKeys
);
await singleProtoJobQueue.add(
MessageSender.getFetchLocalProfileSyncMessage()
);
}
}
// Step #: Save profile `badges` to conversation and update redux
const badges = parseBadgesFromServer(profile.badges, updatesUrl);
if (badges.length) {
window.reduxActions.badges.updateOrCreate(badges);
c.set({
badges: badges.map(badge => ({
id: badge.id,
...('expiresAt' in badge
? {
expiresAt: badge.expiresAt,
isVisible: badge.isVisible,
}
: {}),
})),
});
} else {
c.unset('badges');
}
// Step #: Save updated (or clear if missing) profile `credential` to conversation
if (options.profileCredentialRequestContext != null) {
if (profile.credential != null && profile.credential.length > 0) {
const {
credential: profileKeyCredential,
expiration: profileKeyCredentialExpiration,
} = handleProfileKeyCredential(
clientZkProfileCipher,
options.profileCredentialRequestContext,
profile.credential
);
c.set({ profileKeyCredential, profileKeyCredentialExpiration });
} else {
log.warn(
`${logId}: Included credential request, but got no credential. Clearing profileKeyCredential.`
);
c.unset('profileKeyCredential');
}
}
// TODO: Should this track other failures?
let isSuccessfullyDecrypted = true;
// Step #: Save profile `name` to conversation
if (isFieldDefined(profile.name)) {
if (requestDecryptionKey != null) {
try {
// Note: Writes to DB and saves message
await c.setEncryptedProfileName(profile.name, requestDecryptionKey);
} catch (error) {
log.warn(
`${logId}: Failed to decrypt profile name`,
Errors.toLogFormat(error)
);
isSuccessfullyDecrypted = false;
c.set({
profileName: undefined,
profileFamilyName: undefined,
});
}
}
} else {
c.set({
profileName: undefined,
profileFamilyName: undefined,
});
}
try {
if (requestDecryptionKey != null) {
// Note: Fetches avatar
await c.setAndMaybeFetchProfileAvatar(
profile.avatar,
requestDecryptionKey
);
}
} catch (error) {
if (error instanceof HTTPError) {
// Forbidden/Not Found
if (error.code === 403 || error.code === 404) {
log.warn(`${logId}: Profile avatar is missing (${error.code})`);
}
} else {
log.warn(
`${logId}: Failed to decrypt profile avatar`,
Errors.toLogFormat(error)
);
isSuccessfullyDecrypted = false;
}
}
c.set('profileLastFetchedAt', Date.now());
// After we successfully decrypted - update lastProfile property
if (
isSuccessfullyDecrypted &&
options.profileKey &&
request.profileKeyVersion
) {
await c.updateLastProfile(lastProfile, {
profileKey: options.profileKey,
profileKeyVersion: request.profileKeyVersion,
});
}
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await DataWriter.updateConversation(c.attributes);
}
export type UpdateIdentityKeyOptionsType = Readonly<{
noOverwrite?: boolean;
}>;
export async function updateIdentityKey(
identityKey: Uint8Array,
serviceId: ServiceIdString,
{ noOverwrite = false }: UpdateIdentityKeyOptionsType = {}
): Promise<boolean> {
if (!Bytes.isNotEmpty(identityKey)) {
return false;
}
const changed = await window.textsecure.storage.protocol.saveIdentity(
new Address(serviceId, 1),
identityKey,
false,
{ noOverwrite }
);
if (changed) {
log.info(`updateIdentityKey(${serviceId}): changed`);
// save identity will close all sessions except for .1, so we
// must close that one manually.
const ourAci = window.textsecure.storage.user.getCheckedAci();
await window.textsecure.storage.protocol.archiveSession(
new QualifiedAddress(ourAci, new Address(serviceId, 1))
);
}
return changed;
}