signal-desktop/ts/services/backups/crypto.ts
2024-04-22 16:11:36 +02:00

53 lines
1.6 KiB
TypeScript

// Copyright 2024 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
import memoizee from 'memoizee';
import { strictAssert } from '../../util/assert';
import type { AciString } from '../../types/ServiceId';
import { toAciObject } from '../../util/ServiceId';
import {
deriveBackupKey,
deriveBackupSignatureKey,
deriveBackupId,
deriveBackupKeyMaterial,
} from '../../Crypto';
import type { BackupKeyMaterialType } from '../../Crypto';
const getMemoizedBackupKey = memoizee((masterKey: string) => {
return deriveBackupKey(Buffer.from(masterKey, 'base64'));
});
export function getBackupKey(): Uint8Array {
const masterKey = window.storage.get('masterKey');
strictAssert(masterKey, 'Master key not available');
return getMemoizedBackupKey(masterKey);
}
const getMemoizedBackupSignatureKey = memoizee(
(backupKey: Uint8Array, aci: AciString) => {
const aciBytes = toAciObject(aci).getServiceIdBinary();
return deriveBackupSignatureKey(backupKey, aciBytes);
}
);
export function getBackupSignatureKey(): Uint8Array {
const backupKey = getBackupKey();
const aci = window.storage.user.getCheckedAci();
return getMemoizedBackupSignatureKey(backupKey, aci);
}
const getMemoizedKeyMaterial = memoizee(
(backupKey: Uint8Array, aci: AciString) => {
const aciBytes = toAciObject(aci).getServiceIdBinary();
const backupId = deriveBackupId(backupKey, aciBytes);
return deriveBackupKeyMaterial(backupKey, backupId);
}
);
export function getKeyMaterial(): BackupKeyMaterialType {
const backupKey = getBackupKey();
const aci = window.storage.user.getCheckedAci();
return getMemoizedKeyMaterial(backupKey, aci);
}