convert SessionBackup to typescript and pass in keyloader

This commit is contained in:
Bruno Windels 2022-01-20 11:16:08 +01:00
parent a4d924acd1
commit 993a86ddb2
3 changed files with 117 additions and 69 deletions

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@ -70,6 +70,7 @@ export class Session {
this._e2eeAccount = null; this._e2eeAccount = null;
this._deviceTracker = null; this._deviceTracker = null;
this._olmEncryption = null; this._olmEncryption = null;
this._keyLoader = null;
this._megolmEncryption = null; this._megolmEncryption = null;
this._megolmDecryption = null; this._megolmDecryption = null;
this._getSyncToken = () => this.syncToken; this._getSyncToken = () => this.syncToken;
@ -141,8 +142,8 @@ export class Session {
now: this._platform.clock.now, now: this._platform.clock.now,
ownDeviceId: this._sessionInfo.deviceId, ownDeviceId: this._sessionInfo.deviceId,
}); });
const keyLoader = new MegOlmKeyLoader(this._olm, PICKLE_KEY, 20); this._keyLoader = new MegOlmKeyLoader(this._olm, PICKLE_KEY, 20);
this._megolmDecryption = new MegOlmDecryption(keyLoader, this._olmWorker); this._megolmDecryption = new MegOlmDecryption(this._keyLoader, this._olmWorker);
this._deviceMessageHandler.enableEncryption({olmDecryption, megolmDecryption: this._megolmDecryption}); this._deviceMessageHandler.enableEncryption({olmDecryption, megolmDecryption: this._megolmDecryption});
} }
@ -246,12 +247,14 @@ export class Session {
async _createSessionBackup(ssssKey, txn) { async _createSessionBackup(ssssKey, txn) {
const secretStorage = new SecretStorage({key: ssssKey, platform: this._platform}); const secretStorage = new SecretStorage({key: ssssKey, platform: this._platform});
this._sessionBackup = await SessionBackup.fromSecretStorage({ this._sessionBackup = await SessionBackup.fromSecretStorage(
platform: this._platform, this._platform,
olm: this._olm, secretStorage, this._olm,
hsApi: this._hsApi, secretStorage,
this._hsApi,
this._keyLoader,
txn txn
}); );
if (this._sessionBackup) { if (this._sessionBackup) {
for (const room of this._rooms.values()) { for (const room of this._rooms.values()) {
if (room.isEncrypted) { if (room.isEncrypted) {

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@ -1,62 +0,0 @@
/*
Copyright 2020 The Matrix.org Foundation C.I.C.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
export class SessionBackup {
constructor({backupInfo, decryption, hsApi}) {
this._backupInfo = backupInfo;
this._decryption = decryption;
this._hsApi = hsApi;
}
async getSession(roomId, sessionId, log) {
const sessionResponse = await this._hsApi.roomKeyForRoomAndSession(this._backupInfo.version, roomId, sessionId, {log}).response();
const sessionInfo = this._decryption.decrypt(
sessionResponse.session_data.ephemeral,
sessionResponse.session_data.mac,
sessionResponse.session_data.ciphertext,
);
return JSON.parse(sessionInfo);
}
get version() {
return this._backupInfo.version;
}
dispose() {
this._decryption.free();
}
static async fromSecretStorage({platform, olm, secretStorage, hsApi, txn}) {
const base64PrivateKey = await secretStorage.readSecret("m.megolm_backup.v1", txn);
if (base64PrivateKey) {
const privateKey = new Uint8Array(platform.encoding.base64.decode(base64PrivateKey));
const backupInfo = await hsApi.roomKeysVersion().response();
const expectedPubKey = backupInfo.auth_data.public_key;
const decryption = new olm.PkDecryption();
try {
const pubKey = decryption.init_with_private_key(privateKey);
if (pubKey !== expectedPubKey) {
throw new Error(`Bad backup key, public key does not match. Calculated ${pubKey} but expected ${expectedPubKey}`);
}
} catch(err) {
decryption.free();
throw err;
}
return new SessionBackup({backupInfo, decryption, hsApi});
}
}
}

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@ -0,0 +1,107 @@
/*
Copyright 2020 The Matrix.org Foundation C.I.C.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
import type {HomeServerApi} from "../../net/HomeServerApi";
import type {RoomKey} from "./decryption/RoomKey";
import type {KeyLoader} from "./decryption/KeyLoader";
import type {SecretStorage} from "../../ssss/SecretStorage";
import type {ILogItem} from "../../../logging/types";
import type {Platform} from "../../../platform/web/Platform";
import type {Transaction} from "../../storage/idb/Transaction";
import type * as OlmNamespace from "@matrix-org/olm";
type Olm = typeof OlmNamespace;
type SignatureMap = {
[userId: string]: {[deviceIdAndAlgorithm: string]: string}
}
interface BaseBackupInfo {
version: string,
etag: string,
count: number,
}
const Curve25519Algorithm = "m.megolm_backup.v1.curve25519-aes-sha2";
interface Curve25519BackupInfo extends BaseBackupInfo {
algorithm: typeof Curve25519Algorithm,
auth_data: Curve25519AuthData,
}
interface OtherBackupInfo extends BaseBackupInfo {
algorithm: "other"
};
type BackupInfo = Curve25519BackupInfo | OtherBackupInfo;
interface Curve25519AuthData {
public_key: string,
signatures: SignatureMap
}
type AuthData = Curve25519AuthData;
export class SessionBackup {
constructor(
private readonly backupInfo: BackupInfo,
private readonly decryption: Olm.PkDecryption,
private readonly hsApi: HomeServerApi,
private readonly keyLoader: KeyLoader
) {}
async getSession(roomId: string, sessionId: string, log: ILogItem) {
const sessionResponse = await this.hsApi.roomKeyForRoomAndSession(this.backupInfo.version, roomId, sessionId, {log}).response();
const sessionInfo = this.decryption.decrypt(
sessionResponse.session_data.ephemeral,
sessionResponse.session_data.mac,
sessionResponse.session_data.ciphertext,
);
return JSON.parse(sessionInfo);
}
get version() {
return this.backupInfo.version;
}
dispose() {
this.decryption.free();
}
static async fromSecretStorage(platform: Platform, olm: Olm, secretStorage: SecretStorage, hsApi: HomeServerApi, keyLoader: KeyLoader, txn: Transaction) {
const base64PrivateKey = await secretStorage.readSecret("m.megolm_backup.v1", txn);
if (base64PrivateKey) {
const privateKey = new Uint8Array(platform.encoding.base64.decode(base64PrivateKey));
const backupInfo = await hsApi.roomKeysVersion().response() as BackupInfo;
if (backupInfo.algorithm === Curve25519Algorithm) {
const expectedPubKey = backupInfo.auth_data.public_key;
const decryption = new olm.PkDecryption();
try {
const pubKey = decryption.init_with_private_key(privateKey);
if (pubKey !== expectedPubKey) {
throw new Error(`Bad backup key, public key does not match. Calculated ${pubKey} but expected ${expectedPubKey}`);
}
} catch(err) {
decryption.free();
throw err;
}
return new SessionBackup(backupInfo, decryption, hsApi, keyLoader);
} else {
throw new Error(`Unknown backup algorithm: ${backupInfo.algorithm}`);
}
}
}
}