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Merge pull request #80 from vector-im/bwindels/olm-encrypt

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Implement olm encryption
This commit is contained in:
Bruno Windels 2020-09-03 13:46:36 +00:00 committed by GitHub
commit 90867d9558
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
13 changed files with 706 additions and 102 deletions
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3
src/matrix/DeviceMessageHandler.js
View file

@ -64,6 +64,9 @@ export class DeviceMessageHandler {
}
const readTxn = await this._storage.readTxn([this._storage.storeNames.session]);
const pendingEvents = await this._getPendingEvents(readTxn);
if (pendingEvents.length === 0) {
return;
}
// only know olm for now
const olmEvents = pendingEvents.filter(e => e.content?.algorithm === OLM_ALGORITHM);
const decryptChanges = await this._olmDecryption.decryptAll(olmEvents);

19
src/matrix/Session.js
View file

@ -21,8 +21,11 @@ import {User} from "./User.js";
import {Account as E2EEAccount} from "./e2ee/Account.js";
import {DeviceMessageHandler} from "./DeviceMessageHandler.js";
import {Decryption as OlmDecryption} from "./e2ee/olm/Decryption.js";
import {Encryption as OlmEncryption} from "./e2ee/olm/Encryption.js";
import {Decryption as MegOlmDecryption} from "./e2ee/megolm/Decryption.js";
import {DeviceTracker} from "./e2ee/DeviceTracker.js";
import {LockMap} from "../utils/LockMap.js";
const PICKLE_KEY = "DEFAULT_KEY";
export class Session {
@ -42,18 +45,23 @@ export class Session {
this._olmUtil = null;
this._e2eeAccount = null;
this._deviceTracker = null;
this._olmEncryption = null;
if (olm) {
this._olmUtil = new olm.Utility();
this._deviceTracker = new DeviceTracker({
storage,
getSyncToken: () => this.syncToken,
olmUtil: this._olmUtil,
ownUserId: sessionInfo.userId,
ownDeviceId: sessionInfo.deviceId,
});
}
}
// called once this._e2eeAccount is assigned
_setupEncryption() {
console.log("loaded e2ee account with keys", this._e2eeAccount.identityKeys);
const senderKeyLock = new LockMap();
const olmDecryption = new OlmDecryption({
account: this._e2eeAccount,
pickleKey: PICKLE_KEY,
@ -61,6 +69,17 @@ export class Session {
ownUserId: this._user.id,
storage: this._storage,
olm: this._olm,
senderKeyLock
});
this._olmEncryption = new OlmEncryption({
account: this._e2eeAccount,
pickleKey: PICKLE_KEY,
now: this._clock.now,
ownUserId: this._user.id,
storage: this._storage,
olm: this._olm,
olmUtil: this._olmUtil,
senderKeyLock
});
const megolmDecryption = new MegOlmDecryption({pickleKey: PICKLE_KEY, olm: this._olm});
this._deviceMessageHandler.enableEncryption({olmDecryption, megolmDecryption});

16
src/matrix/e2ee/Account.js
View file

@ -126,8 +126,24 @@ export class Account {
createInboundOlmSession(senderKey, body) {
const newSession = new this._olm.Session();
try {
newSession.create_inbound_from(this._account, senderKey, body);
return newSession;
} catch (err) {
newSession.free();
throw err;
}
}
createOutboundOlmSession(theirIdentityKey, theirOneTimeKey) {
const newSession = new this._olm.Session();
try {
newSession.create_outbound(this._account, theirIdentityKey, theirOneTimeKey);
return newSession;
} catch (err) {
newSession.free();
throw err;
}
}
writeRemoveOneTimeKey(session, txn) {

41
src/matrix/e2ee/DeviceTracker.js
View file

@ -14,13 +14,11 @@ See the License for the specific language governing permissions and
limitations under the License.
*/
import anotherjson from "../../../lib/another-json/index.js";
import {verifyEd25519Signature, SIGNATURE_ALGORITHM} from "./common.js";
const TRACKING_STATUS_OUTDATED = 0;
const TRACKING_STATUS_UPTODATE = 1;
const DEVICE_KEYS_SIGNATURE_ALGORITHM = "ed25519";
// map 1 device from /keys/query response to DeviceIdentity
function deviceKeysAsDeviceIdentity(deviceSection) {
const deviceId = deviceSection["device_id"];
@ -36,11 +34,13 @@ function deviceKeysAsDeviceIdentity(deviceSection) {
}
export class DeviceTracker {
constructor({storage, getSyncToken, olmUtil}) {
constructor({storage, getSyncToken, olmUtil, ownUserId, ownDeviceId}) {
this._storage = storage;
this._getSyncToken = getSyncToken;
this._identityChangedForRoom = null;
this._olmUtil = olmUtil;
this._ownUserId = ownUserId;
this._ownDeviceId = ownDeviceId;
}
async writeDeviceChanges(deviceLists, txn) {
@ -200,7 +200,11 @@ export class DeviceTracker {
if (deviceIdOnKeys !== deviceId) {
return false;
}
return this._verifyUserDeviceKeys(deviceKeys);
// don't store our own device
if (userId === this._ownUserId && deviceId === this._ownDeviceId) {
return false;
}
return this._hasValidSignature(deviceKeys);
});
const verifiedKeys = verifiedEntries.map(([, deviceKeys]) => deviceKeys);
return {userId, verifiedKeys};
@ -208,26 +212,11 @@ export class DeviceTracker {
return verifiedKeys;
}
_verifyUserDeviceKeys(deviceSection) {
_hasValidSignature(deviceSection) {
const deviceId = deviceSection["device_id"];
const userId = deviceSection["user_id"];
const clone = Object.assign({}, deviceSection);
delete clone.unsigned;
delete clone.signatures;
const canonicalJson = anotherjson.stringify(clone);
const key = deviceSection?.keys?.[`${DEVICE_KEYS_SIGNATURE_ALGORITHM}:${deviceId}`];
const signature = deviceSection?.signatures?.[userId]?.[`${DEVICE_KEYS_SIGNATURE_ALGORITHM}:${deviceId}`];
try {
if (!signature) {
throw new Error("no signature");
}
// throws when signature is invalid
this._olmUtil.ed25519_verify(key, canonicalJson, signature);
return true;
} catch (err) {
console.warn("Invalid device signature, ignoring device.", key, canonicalJson, signature, err);
return false;
}
const ed25519Key = deviceSection?.keys?.[`${SIGNATURE_ALGORITHM}:${deviceId}`];
return verifyEd25519Signature(this._olmUtil, userId, deviceId, ed25519Key, deviceSection);
}
/**
@ -275,6 +264,10 @@ export class DeviceTracker {
if (queriedDevices && queriedDevices.length) {
flattenedDevices = flattenedDevices.concat(queriedDevices);
}
return flattenedDevices;
// filter out our own devices if it got in somehow (even though we should not store it)
const devices = flattenedDevices.filter(device => {
return !(device.userId === this._ownUserId && device.deviceId === this._ownDeviceId);
});
return devices;
}
}

23
src/matrix/e2ee/common.js
View file

@ -14,6 +14,8 @@ See the License for the specific language governing permissions and
limitations under the License.
*/
import anotherjson from "../../../lib/another-json/index.js";
// use common prefix so it's easy to clear properties that are not e2ee related during session clear
export const SESSION_KEY_PREFIX = "e2ee:";
export const OLM_ALGORITHM = "m.olm.v1.curve25519-aes-sha2";
@ -27,3 +29,24 @@ export class DecryptionError extends Error {
this.details = detailsObj;
}
}
export const SIGNATURE_ALGORITHM = "ed25519";
export function verifyEd25519Signature(olmUtil, userId, deviceOrKeyId, ed25519Key, value) {
const clone = Object.assign({}, value);
delete clone.unsigned;
delete clone.signatures;
const canonicalJson = anotherjson.stringify(clone);
const signature = value?.signatures?.[userId]?.[`${SIGNATURE_ALGORITHM}:${deviceOrKeyId}`];
try {
if (!signature) {
throw new Error("no signature");
}
// throws when signature is invalid
olmUtil.ed25519_verify(ed25519Key, canonicalJson, signature);
return true;
} catch (err) {
console.warn("Invalid signature, ignoring.", ed25519Key, canonicalJson, signature, err);
return false;
}
}

86
src/matrix/e2ee/olm/Decryption.js
View file

@ -15,6 +15,8 @@ limitations under the License.
*/
import {DecryptionError} from "../common.js";
import {groupBy} from "../../../utils/groupBy.js";
import {Session} from "./Session.js";
const SESSION_LIMIT_PER_SENDER_KEY = 4;
@ -29,14 +31,14 @@ function sortSessions(sessions) {
}
export class Decryption {
constructor({account, pickleKey, now, ownUserId, storage, olm}) {
constructor({account, pickleKey, now, ownUserId, storage, olm, senderKeyLock}) {
this._account = account;
this._pickleKey = pickleKey;
this._now = now;
this._ownUserId = ownUserId;
this._storage = storage;
this._olm = olm;
this._createOutboundSessionPromise = null;
this._senderKeyLock = senderKeyLock;
}
// we need decryptAll because there is some parallelization we can do for decrypting different sender keys at once
@ -49,17 +51,14 @@ export class Decryption {
//
// doing it one by one would be possible, but we would lose the opportunity for parallelization
async decryptAll(events) {
const eventsPerSenderKey = events.reduce((map, event) => {
const senderKey = event.content?.["sender_key"];
let list = map.get(senderKey);
if (!list) {
list = [];
map.set(senderKey, list);
}
list.push(event);
return map;
}, new Map());
const eventsPerSenderKey = groupBy(events, event => event.content?.["sender_key"]);
const timestamp = this._now();
// take a lock on all senderKeys so encryption or other calls to decryptAll (should not happen)
// don't modify the sessions at the same time
const locks = await Promise.all(Array.from(eventsPerSenderKey.keys()).map(senderKey => {
return this._senderKeyLock.takeLock(senderKey);
}));
try {
const readSessionsTxn = await this._storage.readTxn([this._storage.storeNames.olmSessions]);
// decrypt events for different sender keys in parallel
const results = await Promise.all(Array.from(eventsPerSenderKey.entries()).map(([senderKey, events]) => {
@ -68,7 +67,14 @@ export class Decryption {
const payloads = results.reduce((all, r) => all.concat(r.payloads), []);
const errors = results.reduce((all, r) => all.concat(r.errors), []);
const senderKeyDecryptions = results.map(r => r.senderKeyDecryption);
return new DecryptionChanges(senderKeyDecryptions, payloads, errors);
return new DecryptionChanges(senderKeyDecryptions, payloads, errors, this._account, locks);
} catch (err) {
// make sure the locks are release if something throws
for (const lock of locks) {
lock.release();
}
throw err;
}
}
async _decryptAllForSenderKey(senderKey, events, timestamp, readSessionsTxn) {
@ -105,7 +111,12 @@ export class Decryption {
plaintext = createResult.plaintext;
}
if (typeof plaintext === "string") {
const payload = JSON.parse(plaintext);
let payload;
try {
payload = JSON.parse(plaintext);
} catch (err) {
throw new DecryptionError("Could not JSON decode plaintext", event, {plaintext, err});
}
this._validatePayload(payload, event);
return {event: payload, senderKey};
} else {
@ -177,44 +188,6 @@ export class Decryption {
}
}
class Session {
constructor(data, pickleKey, olm, isNew = false) {
this.data = data;
this._olm = olm;
this._pickleKey = pickleKey;
this.isNew = isNew;
this.isModified = isNew;
}
static create(senderKey, olmSession, olm, pickleKey, timestamp) {
return new Session({
session: olmSession.pickle(pickleKey),
sessionId: olmSession.session_id(),
senderKey,
lastUsed: timestamp,
}, pickleKey, olm, true);
}
get id() {
return this.data.sessionId;
}
load() {
const session = new this._olm.Session();
session.unpickle(this._pickleKey, this.data.session);
return session;
}
unload(olmSession) {
olmSession.free();
}
save(olmSession) {
this.data.session = olmSession.pickle(this._pickleKey);
this.isModified = true;
}
}
// decryption helper for a single senderKey
class SenderKeyDecryption {
constructor(senderKey, sessions, olm, timestamp) {
@ -280,11 +253,12 @@ class SenderKeyDecryption {
}
class DecryptionChanges {
constructor(senderKeyDecryptions, payloads, errors, account) {
constructor(senderKeyDecryptions, payloads, errors, account, locks) {
this._senderKeyDecryptions = senderKeyDecryptions;
this._account = account;
this.payloads = payloads;
this.errors = errors;
this._locks = locks;
}
get hasNewSessions() {
@ -292,6 +266,7 @@ class DecryptionChanges {
}
write(txn) {
try {
for (const senderKeyDecryption of this._senderKeyDecryptions) {
for (const session of senderKeyDecryption.getModifiedSessions()) {
txn.olmSessions.set(session.data);
@ -313,5 +288,10 @@ class DecryptionChanges {
}
}
}
} finally {
for (const lock of this._locks) {
lock.release();
}
}
}
}

274
src/matrix/e2ee/olm/Encryption.js Normal file
View file

@ -0,0 +1,274 @@
/*
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 {groupByWithCreator} from "../../../utils/groupBy.js";
import {verifyEd25519Signature, OLM_ALGORITHM} from "../common.js";
import {createSessionEntry} from "./Session.js";
function findFirstSessionId(sessionIds) {
return sessionIds.reduce((first, sessionId) => {
if (!first || sessionId < first) {
return sessionId;
} else {
return first;
}
}, null);
}
const OTK_ALGORITHM = "signed_curve25519";
export class Encryption {
constructor({account, olm, olmUtil, ownUserId, storage, now, pickleKey, senderKeyLock}) {
this._account = account;
this._olm = olm;
this._olmUtil = olmUtil;
this._ownUserId = ownUserId;
this._storage = storage;
this._now = now;
this._pickleKey = pickleKey;
this._senderKeyLock = senderKeyLock;
}
async encrypt(type, content, devices, hsApi) {
// TODO: see if we can only hold some of the locks until after the /keys/claim call (if needed)
// take a lock on all senderKeys so decryption and other calls to encrypt (should not happen)
// don't modify the sessions at the same time
const locks = await Promise.all(devices.map(device => {
return this._senderKeyLock.takeLock(device.curve25519Key);
}));
try {
const {
devicesWithoutSession,
existingEncryptionTargets,
} = await this._findExistingSessions(devices);
const timestamp = this._now();
let encryptionTargets = [];
try {
if (devicesWithoutSession.length) {
const newEncryptionTargets = await this._createNewSessions(
devicesWithoutSession, hsApi, timestamp);
encryptionTargets = encryptionTargets.concat(newEncryptionTargets);
}
await this._loadSessions(existingEncryptionTargets);
encryptionTargets = encryptionTargets.concat(existingEncryptionTargets);
const messages = encryptionTargets.map(target => {
const encryptedContent = this._encryptForDevice(type, content, target);
return new EncryptedMessage(encryptedContent, target.device);
});
await this._storeSessions(encryptionTargets, timestamp);
return messages;
} finally {
for (const target of encryptionTargets) {
target.dispose();
}
}
} finally {
for (const lock of locks) {
lock.release();
}
}
}
async _findExistingSessions(devices) {
const txn = await this._storage.readTxn([this._storage.storeNames.olmSessions]);
const sessionIdsForDevice = await Promise.all(devices.map(async device => {
return await txn.olmSessions.getSessionIds(device.curve25519Key);
}));
const devicesWithoutSession = devices.filter((_, i) => {
const sessionIds = sessionIdsForDevice[i];
return !(sessionIds?.length);
});
const existingEncryptionTargets = devices.map((device, i) => {
const sessionIds = sessionIdsForDevice[i];
if (sessionIds?.length > 0) {
const sessionId = findFirstSessionId(sessionIds);
return EncryptionTarget.fromSessionId(device, sessionId);
}
}).filter(target => !!target);
return {devicesWithoutSession, existingEncryptionTargets};
}
_encryptForDevice(type, content, target) {
const {session, device} = target;
const plaintext = JSON.stringify(this._buildPlainTextMessageForDevice(type, content, device));
const message = session.encrypt(plaintext);
const encryptedContent = {
algorithm: OLM_ALGORITHM,
sender_key: this._account.identityKeys.curve25519,
ciphertext: {
[device.curve25519Key]: message
}
};
return encryptedContent;
}
_buildPlainTextMessageForDevice(type, content, device) {
return {
keys: {
"ed25519": this._account.identityKeys.ed25519
},
recipient_keys: {
"ed25519": device.ed25519Key
},
recipient: device.userId,
sender: this._ownUserId,
content,
type
}
}
async _createNewSessions(devicesWithoutSession, hsApi, timestamp) {
const newEncryptionTargets = await this._claimOneTimeKeys(hsApi, devicesWithoutSession);
try {
for (const target of newEncryptionTargets) {
const {device, oneTimeKey} = target;
target.session = this._account.createOutboundOlmSession(device.curve25519Key, oneTimeKey);
}
this._storeSessions(newEncryptionTargets, timestamp);
} catch (err) {
for (const target of newEncryptionTargets) {
target.dispose();
}
throw err;
}
return newEncryptionTargets;
}
async _claimOneTimeKeys(hsApi, deviceIdentities) {
// create a Map<userId, Map<deviceId, deviceIdentity>>
const devicesByUser = groupByWithCreator(deviceIdentities,
device => device.userId,
() => new Map(),
(deviceMap, device) => deviceMap.set(device.deviceId, device)
);
const oneTimeKeys = Array.from(devicesByUser.entries()).reduce((usersObj, [userId, deviceMap]) => {
usersObj[userId] = Array.from(deviceMap.values()).reduce((devicesObj, device) => {
devicesObj[device.deviceId] = OTK_ALGORITHM;
return devicesObj;
}, {});
return usersObj;
}, {});
const claimResponse = await hsApi.claimKeys({
timeout: 10000,
one_time_keys: oneTimeKeys
}).response();
// TODO: log claimResponse.failures
const userKeyMap = claimResponse?.["one_time_keys"];
return this._verifyAndCreateOTKTargets(userKeyMap, devicesByUser);
}
_verifyAndCreateOTKTargets(userKeyMap, devicesByUser) {
const verifiedEncryptionTargets = [];
for (const [userId, userSection] of Object.entries(userKeyMap)) {
for (const [deviceId, deviceSection] of Object.entries(userSection)) {
const [firstPropName, keySection] = Object.entries(deviceSection)[0];
const [keyAlgorithm] = firstPropName.split(":");
if (keyAlgorithm === OTK_ALGORITHM) {
const device = devicesByUser.get(userId)?.get(deviceId);
if (device) {
const isValidSignature = verifyEd25519Signature(
this._olmUtil, userId, deviceId, device.ed25519Key, keySection);
if (isValidSignature) {
const target = EncryptionTarget.fromOTK(device, keySection.key);
verifiedEncryptionTargets.push(target);
}
}
}
}
}
return verifiedEncryptionTargets;
}
async _loadSessions(encryptionTargets) {
const txn = await this._storage.readTxn([this._storage.storeNames.olmSessions]);
// given we run loading in parallel, there might still be some
// storage requests that will finish later once one has failed.
// those should not allocate a session anymore.
let failed = false;
try {
await Promise.all(encryptionTargets.map(async encryptionTarget => {
const sessionEntry = await txn.olmSessions.get(
encryptionTarget.device.curve25519Key, encryptionTarget.sessionId);
if (sessionEntry && !failed) {
const olmSession = new this._olm.Session();
olmSession.unpickle(this._pickleKey, sessionEntry.session);
encryptionTarget.session = olmSession;
}
}));
} catch (err) {
failed = true;
// clean up the sessions that did load
for (const target of encryptionTargets) {
target.dispose();
}
throw err;
}
}
async _storeSessions(encryptionTargets, timestamp) {
const txn = await this._storage.readWriteTxn([this._storage.storeNames.olmSessions]);
try {
for (const target of encryptionTargets) {
const sessionEntry = createSessionEntry(
target.session, target.device.curve25519Key, timestamp, this._pickleKey);
txn.olmSessions.set(sessionEntry);
}
} catch (err) {
txn.abort();
throw err;
}
await txn.complete();
}
}
// just a container needed to encrypt a message for a recipient device
// it is constructed with either a oneTimeKey
// (and later converted to a session) in case of a new session
// or an existing session
class EncryptionTarget {
constructor(device, oneTimeKey, sessionId) {
this.device = device;
this.oneTimeKey = oneTimeKey;
this.sessionId = sessionId;
// an olmSession, should probably be called olmSession
this.session = null;
}
static fromOTK(device, oneTimeKey) {
return new EncryptionTarget(device, oneTimeKey, null);
}
static fromSessionId(device, sessionId) {
return new EncryptionTarget(device, null, sessionId);
}
dispose() {
if (this.session) {
this.session.free();
}
}
}
class EncryptedMessage {
constructor(content, device) {
this.content = content;
this.device = device;
}
}

58
src/matrix/e2ee/olm/Session.js Normal file
View file

@ -0,0 +1,58 @@
/*
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 function createSessionEntry(olmSession, senderKey, timestamp, pickleKey) {
return {
session: olmSession.pickle(pickleKey),
sessionId: olmSession.session_id(),
senderKey,
lastUsed: timestamp,
};
}
export class Session {
constructor(data, pickleKey, olm, isNew = false) {
this.data = data;
this._olm = olm;
this._pickleKey = pickleKey;
this.isNew = isNew;
this.isModified = isNew;
}
static create(senderKey, olmSession, olm, pickleKey, timestamp) {
const data = createSessionEntry(olmSession, senderKey, timestamp, pickleKey);
return new Session(data, pickleKey, olm, true);
}
get id() {
return this.data.sessionId;
}
load() {
const session = new this._olm.Session();
session.unpickle(this._pickleKey, this.data.session);
return session;
}
unload(olmSession) {
olmSession.free();
}
save(olmSession) {
this.data.session = olmSession.pickle(this._pickleKey);
this.isModified = true;
}
}

4
src/matrix/net/HomeServerApi.js
View file

@ -168,6 +168,10 @@ export class HomeServerApi {
return this._post("/keys/query", null, queryRequest, options);
}
claimKeys(payload, options = null) {
return this._post("/keys/claim", null, payload, options);
}
get mediaRepository() {
return this._mediaRepository;
}

20
src/matrix/storage/idb/stores/OlmSessionStore.js
View file

@ -18,11 +18,31 @@ function encodeKey(senderKey, sessionId) {
return `${senderKey}|${sessionId}`;
}
function decodeKey(key) {
const [senderKey, sessionId] = key.split("|");
return {senderKey, sessionId};
}
export class OlmSessionStore {
constructor(store) {
this._store = store;
}
async getSessionIds(senderKey) {
const sessionIds = [];
const range = IDBKeyRange.lowerBound(encodeKey(senderKey, ""));
await this._store.iterateKeys(range, key => {
const decodedKey = decodeKey(key);
// prevent running into the next room
if (decodedKey.senderKey === senderKey) {
sessionIds.push(decodedKey.sessionId);
return false; // fetch more
}
return true; // done
});
return sessionIds;
}
getAll(senderKey) {
const range = IDBKeyRange.lowerBound(encodeKey(senderKey, ""));
return this._store.selectWhile(range, session => {

86
src/utils/Lock.js Normal file
View file

@ -0,0 +1,86 @@
/*
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 Lock {
constructor() {
this._promise = null;
this._resolve = null;
}
take() {
if (!this._promise) {
this._promise = new Promise(resolve => {
this._resolve = resolve;
});
return true;
}
return false;
}
get isTaken() {
return !!this._promise;
}
release() {
if (this._resolve) {
this._promise = null;
const resolve = this._resolve;
this._resolve = null;
resolve();
}
}
released() {
return this._promise;
}
}
export function tests() {
return {
"taking a lock twice returns false": assert => {
const lock = new Lock();
assert.equal(lock.take(), true);
assert.equal(lock.isTaken, true);
assert.equal(lock.take(), false);
},
"can take a released lock again": assert => {
const lock = new Lock();
lock.take();
lock.release();
assert.equal(lock.isTaken, false);
assert.equal(lock.take(), true);
},
"2 waiting for lock, only first one gets it": async assert => {
const lock = new Lock();
lock.take();
let first;
lock.released().then(() => first = lock.take());
let second;
lock.released().then(() => second = lock.take());
const promise = lock.released();
lock.release();
await promise;
assert.strictEqual(first, true);
assert.strictEqual(second, false);
},
"await non-taken lock": async assert => {
const lock = new Lock();
await lock.released();
assert(true);
}
}
}

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/*
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 {Lock} from "./Lock.js";
export class LockMap {
constructor() {
this._map = new Map();
}
async takeLock(key) {
let lock = this._map.get(key);
if (lock) {
while (!lock.take()) {
await lock.released();
}
} else {
lock = new Lock();
lock.take();
this._map.set(key, lock);
}
// don't leave old locks lying around
lock.released().then(() => {
// give others a chance to take the lock first
Promise.resolve().then(() => {
if (!lock.isTaken) {
this._map.delete(key);
}
});
});
return lock;
}
}
export function tests() {
return {
"taking a lock on the same key blocks": async assert => {
const lockMap = new LockMap();
const lock = await lockMap.takeLock("foo");
let second = false;
const prom = lockMap.takeLock("foo").then(() => {
second = true;
});
assert.equal(second, false);
// do a delay to make sure prom does not resolve on its own
await Promise.resolve();
lock.release();
await prom;
assert.equal(second, true);
},
"lock is not cleaned up with second request": async assert => {
const lockMap = new LockMap();
const lock = await lockMap.takeLock("foo");
let ranSecond = false;
const prom = lockMap.takeLock("foo").then(returnedLock => {
ranSecond = true;
assert.equal(returnedLock.isTaken, true);
// peek into internals, naughty
assert.equal(lockMap._map.get("foo"), returnedLock);
});
lock.release();
await prom;
// double delay to make sure cleanup logic ran
await Promise.resolve();
await Promise.resolve();
assert.equal(ranSecond, true);
},
"lock is cleaned up without other request": async assert => {
const lockMap = new LockMap();
const lock = await lockMap.takeLock("foo");
await Promise.resolve();
lock.release();
// double delay to make sure cleanup logic ran
await Promise.resolve();
await Promise.resolve();
assert.equal(lockMap._map.has("foo"), false);
},
};
}

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/*
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 function groupBy(array, groupFn) {
return groupByWithCreator(array, groupFn,
() => {return [];},
(array, value) => array.push(value)
);
}
export function groupByWithCreator(array, groupFn, createCollectionFn, addCollectionFn) {
return array.reduce((map, value) => {
const key = groupFn(value);
let collection = map.get(key);
if (!collection) {
collection = createCollectionFn();
map.set(key, collection);
}
addCollectionFn(collection, value);
return map;
}, new Map());
}