convert megolm/Decryption to typescript and adapt to KeyLoader

This commit is contained in:
Bruno Windels 2021-10-22 17:46:39 +02:00
parent 2ddb3fbf72
commit d6e243321b

View file

@ -15,23 +15,26 @@ limitations under the License.
*/ */
import {DecryptionError} from "../common.js"; import {DecryptionError} from "../common.js";
import * as RoomKey from "./decryption/RoomKey";
import {SessionInfo} from "./decryption/SessionInfo.js";
import {DecryptionPreparation} from "./decryption/DecryptionPreparation.js"; import {DecryptionPreparation} from "./decryption/DecryptionPreparation.js";
import {SessionDecryption} from "./decryption/SessionDecryption.js"; import {SessionDecryption} from "./decryption/SessionDecryption";
import {SessionCache} from "./decryption/SessionCache.js";
import {MEGOLM_ALGORITHM} from "../common.js"; import {MEGOLM_ALGORITHM} from "../common.js";
import {validateEvent, groupEventsBySession} from "./decryption/utils.js"; import {validateEvent, groupEventsBySession} from "./decryption/utils";
import {keyFromStorage, keyFromDeviceMessage, keyFromBackup} from "./decryption/RoomKey";
import type {IRoomKey, IIncomingRoomKey} from "./decryption/RoomKey";
import type {KeyLoader} from "./decryption/KeyLoader";
import type {OlmWorker} from "../OlmWorker";
import type {Transaction} from "../../storage/idb/Transaction";
import type {TimelineEvent} from "../../storage/types";
import type {DecryptionResult} from "../DecryptionResult";
import type {LogItem} from "../../../logging/LogItem";
export class Decryption { export class Decryption {
constructor({pickleKey, olm, olmWorker}) { private keyLoader: KeyLoader;
this._pickleKey = pickleKey; private olmWorker?: OlmWorker;
this._olm = olm;
this._olmWorker = olmWorker;
}
createSessionCache(size) { constructor(keyLoader: KeyLoader, olmWorker: OlmWorker | undefined) {
return new SessionCache(size); this.keyLoader = keyLoader;
this.olmWorker = olmWorker;
} }
async addMissingKeyEventIds(roomId, senderKey, sessionId, eventIds, txn) { async addMissingKeyEventIds(roomId, senderKey, sessionId, eventIds, txn) {
@ -75,9 +78,9 @@ export class Decryption {
* @param {[type]} txn [description] * @param {[type]} txn [description]
* @return {DecryptionPreparation} * @return {DecryptionPreparation}
*/ */
async prepareDecryptAll(roomId, events, newKeys, sessionCache, txn) { async prepareDecryptAll(roomId: string, events: TimelineEvent[], newKeys: IIncomingRoomKey[] | undefined, txn: Transaction) {
const errors = new Map(); const errors = new Map();
const validEvents = []; const validEvents: TimelineEvent[] = [];
for (const event of events) { for (const event of events) {
if (validateEvent(event)) { if (validateEvent(event)) {
@ -89,11 +92,11 @@ export class Decryption {
const eventsBySession = groupEventsBySession(validEvents); const eventsBySession = groupEventsBySession(validEvents);
const sessionDecryptions = []; const sessionDecryptions: SessionDecryption[] = [];
await Promise.all(Array.from(eventsBySession.values()).map(async group => { await Promise.all(Array.from(eventsBySession.values()).map(async group => {
const sessionInfo = await this._getSessionInfo(roomId, group.senderKey, group.sessionId, newKeys, sessionCache, txn); const key = await this.getRoomKey(roomId, group.senderKey!, group.sessionId!, newKeys, txn);
if (sessionInfo) { if (key) {
sessionDecryptions.push(new SessionDecryption(sessionInfo, group.events, this._olmWorker)); sessionDecryptions.push(new SessionDecryption(key, group.events, this.olmWorker, this.keyLoader));
} else { } else {
for (const event of group.events) { for (const event of group.events) {
errors.set(event.event_id, new DecryptionError("MEGOLM_NO_SESSION", event)); errors.set(event.event_id, new DecryptionError("MEGOLM_NO_SESSION", event));
@ -104,64 +107,43 @@ export class Decryption {
return new DecryptionPreparation(roomId, sessionDecryptions, errors); return new DecryptionPreparation(roomId, sessionDecryptions, errors);
} }
async _getSessionInfo(roomId, senderKey, sessionId, newKeys, sessionCache, txn) { private async getRoomKey(roomId: string, senderKey: string, sessionId: string, newKeys: IIncomingRoomKey[] | undefined, txn: Transaction): Promise<IRoomKey | undefined> {
let sessionInfo;
if (newKeys) { if (newKeys) {
const key = newKeys.find(k => k.roomId === roomId && k.senderKey === senderKey && k.sessionId === sessionId); const key = newKeys.find(k => k.roomId === roomId && k.senderKey === senderKey && k.sessionId === sessionId);
if (key) { if (key && await key.checkBetterThanKeyInStorage(this.keyLoader, txn)) {
sessionInfo = await key.createSessionInfo(this._olm, this._pickleKey, txn); return key;
if (sessionInfo) {
sessionCache.add(sessionInfo);
}
} }
} }
// look only in the cache after looking into newKeys as it may contains that are better // look only in the cache after looking into newKeys as it may contains that are better
if (!sessionInfo) { const cachedKey = this.keyLoader.getCachedKey(roomId, senderKey, sessionId);
sessionInfo = sessionCache.get(roomId, senderKey, sessionId); if (cachedKey) {
// TODO: shouldn't we retain here? return cachedKey;
} }
if (!sessionInfo) { const storageKey = await keyFromStorage(roomId, senderKey, sessionId, txn);
const sessionEntry = await txn.inboundGroupSessions.get(roomId, senderKey, sessionId); if (storageKey && storageKey.serializationKey) {
if (sessionEntry && sessionEntry.session) { return storageKey;
let session = new this._olm.InboundGroupSession();
try {
session.unpickle(this._pickleKey, sessionEntry.session);
sessionInfo = new SessionInfo(roomId, senderKey, session, sessionEntry.claimedKeys);
} catch (err) {
session.free();
throw err;
} }
sessionCache.add(sessionInfo);
}
}
return sessionInfo;
} }
/** /**
* Writes the key as an inbound group session if there is not already a better key in the store * Writes the key as an inbound group session if there is not already a better key in the store
* @param {RoomKey} key
* @param {Transaction} txn a storage transaction with read/write on inboundGroupSessions
* @return {Promise<boolean>} whether the key was the best for the sessio id and was written
*/ */
writeRoomKey(key, txn) { writeRoomKey(key: IIncomingRoomKey, txn: Transaction): Promise<boolean> {
return key.write(this._olm, this._pickleKey, txn); return key.write(this.keyLoader, txn);
} }
/** /**
* Extracts room keys from decrypted device messages. * Extracts room keys from decrypted device messages.
* The key won't be persisted yet, you need to call RoomKey.write for that. * The key won't be persisted yet, you need to call RoomKey.write for that.
*
* @param {Array<OlmDecryptionResult>} decryptionResults, any non megolm m.room_key messages will be ignored.
* @return {Array<RoomKey>} an array with validated RoomKey's. Note that it is possible we already have a better version of this key in storage though; writing the key will tell you so.
*/ */
roomKeysFromDeviceMessages(decryptionResults, log) { roomKeysFromDeviceMessages(decryptionResults: DecryptionResult[], log: LogItem): IIncomingRoomKey[] {
let keys = []; let keys: IIncomingRoomKey[] = [];
for (const dr of decryptionResults) { for (const dr of decryptionResults) {
if (dr.event?.type !== "m.room_key" || dr.event.content?.algorithm !== MEGOLM_ALGORITHM) { if (dr.event?.type !== "m.room_key" || dr.event.content?.algorithm !== MEGOLM_ALGORITHM) {
continue; continue;
} }
log.wrap("room_key", log => { log.wrap("room_key", log => {
const key = RoomKey.fromDeviceMessage(dr); const key = keyFromDeviceMessage(dr);
if (key) { if (key) {
log.set("roomId", key.roomId); log.set("roomId", key.roomId);
log.set("id", key.sessionId); log.set("id", key.sessionId);
@ -175,8 +157,11 @@ export class Decryption {
return keys; return keys;
} }
roomKeyFromBackup(roomId, sessionId, sessionInfo) { roomKeyFromBackup(roomId: string, sessionId: string, sessionInfo: string): IIncomingRoomKey | undefined {
return RoomKey.fromBackup(roomId, sessionId, sessionInfo); return keyFromBackup(roomId, sessionId, sessionInfo);
}
dispose() {
this.keyLoader.dispose();
} }
} }