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Merge pull request #5483 from uhoreg/web_pickle

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Use random pickle key on all platforms
This commit is contained in:
Hubert Chathi 2020-12-15 12:56:41 -05:00 committed by GitHub
commit 983ffe98ff
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4 changed files with 273 additions and 39 deletions
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68
src/BasePlatform.ts
View file

@ -18,6 +18,7 @@ limitations under the License.
*/
import {MatrixClient} from "matrix-js-sdk/src/client";
import {encodeUnpaddedBase64} from "matrix-js-sdk/src/crypto/olmlib";
import dis from './dispatcher/dispatcher';
import BaseEventIndexManager from './indexing/BaseEventIndexManager';
import {ActionPayload} from "./dispatcher/payloads";
@ -25,6 +26,7 @@ import {CheckUpdatesPayload} from "./dispatcher/payloads/CheckUpdatesPayload";
import {Action} from "./dispatcher/actions";
import {hideToast as hideUpdateToast} from "./toasts/UpdateToast";
import {MatrixClientPeg} from "./MatrixClientPeg";
import {idbLoad, idbSave, idbDelete} from "./utils/StorageManager";
export const SSO_HOMESERVER_URL_KEY = "mx_sso_hs_url";
export const SSO_ID_SERVER_URL_KEY = "mx_sso_is_url";
@ -273,8 +275,41 @@ export default abstract class BasePlatform {
* pickle key has been stored.
*/
async getPickleKey(userId: string, deviceId: string): Promise<string | null> {
if (!window.crypto || !window.crypto.subtle) {
return null;
}
let data;
try {
data = await idbLoad("pickleKey", [userId, deviceId]);
} catch (e) {}
if (!data) {
return null;
}
if (!data.encrypted || !data.iv || !data.cryptoKey) {
console.error("Badly formatted pickle key");
return null;
}
const additionalData = new Uint8Array(userId.length + deviceId.length + 1);
for (let i = 0; i < userId.length; i++) {
additionalData[i] = userId.charCodeAt(i);
}
additionalData[userId.length] = 124; // "|"
for (let i = 0; i < deviceId.length; i++) {
additionalData[userId.length + 1 + i] = deviceId.charCodeAt(i);
}
try {
const key = await crypto.subtle.decrypt(
{name: "AES-GCM", iv: data.iv, additionalData}, data.cryptoKey,
data.encrypted,
);
return encodeUnpaddedBase64(key);
} catch (e) {
console.error("Error decrypting pickle key");
return null;
}
}
/**
* Create and store a pickle key for encrypting libolm objects.
@ -284,8 +319,38 @@ export default abstract class BasePlatform {
* support storing pickle keys.
*/
async createPickleKey(userId: string, deviceId: string): Promise<string | null> {
if (!window.crypto || !window.crypto.subtle) {
return null;
}
const crypto = window.crypto;
const randomArray = new Uint8Array(32);
crypto.getRandomValues(randomArray);
const cryptoKey = await crypto.subtle.generateKey(
{name: "AES-GCM", length: 256}, false, ["encrypt", "decrypt"],
);
const iv = new Uint8Array(32);
crypto.getRandomValues(iv);
const additionalData = new Uint8Array(userId.length + deviceId.length + 1);
for (let i = 0; i < userId.length; i++) {
additionalData[i] = userId.charCodeAt(i);
}
additionalData[userId.length] = 124; // "|"
for (let i = 0; i < deviceId.length; i++) {
additionalData[userId.length + 1 + i] = deviceId.charCodeAt(i);
}
const encrypted = await crypto.subtle.encrypt(
{name: "AES-GCM", iv, additionalData}, cryptoKey, randomArray,
);
try {
await idbSave("pickleKey", [userId, deviceId], {encrypted, iv, cryptoKey});
} catch (e) {
return null;
}
return encodeUnpaddedBase64(randomArray);
}
/**
* Delete a previously stored pickle key from storage.
@ -293,5 +358,8 @@ export default abstract class BasePlatform {
* @param {string} userId the device ID that the pickle key is for.
*/
async destroyPickleKey(userId: string, deviceId: string): Promise<void> {
try {
await idbDelete("pickleKey", [userId, deviceId]);
} catch (e) {}
}
}

161
src/Lifecycle.ts
View file

@ -21,6 +21,7 @@ limitations under the License.
import Matrix from 'matrix-js-sdk';
import { InvalidStoreError } from "matrix-js-sdk/src/errors";
import { MatrixClient } from "matrix-js-sdk/src/client";
import {decryptAES, encryptAES} from "matrix-js-sdk/src/crypto/aes";
import {IMatrixClientCreds, MatrixClientPeg} from './MatrixClientPeg';
import SecurityCustomisations from "./customisations/Security";
@ -147,20 +148,13 @@ export async function loadSession(opts: ILoadSessionOpts = {}): Promise<boolean>
* Gets the user ID of the persisted session, if one exists. This does not validate
* that the user's credentials still work, just that they exist and that a user ID
* is associated with them. The session is not loaded.
* @returns {String} The persisted session's owner, if an owner exists. Null otherwise.
* @returns {[String, bool]} The persisted session's owner and whether the stored
* session is for a guest user, if an owner exists. If there is no stored session,
* return [null, null].
*/
export function getStoredSessionOwner(): string {
const {hsUrl, userId, accessToken} = getLocalStorageSessionVars();
return hsUrl && userId && accessToken ? userId : null;
}
/**
* @returns {bool} True if the stored session is for a guest user or false if it is
* for a real user. If there is no stored session, return null.
*/
export function getStoredSessionIsGuest(): boolean {
const sessVars = getLocalStorageSessionVars();
return sessVars.hsUrl && sessVars.userId && sessVars.accessToken ? sessVars.isGuest : null;
export async function getStoredSessionOwner(): Promise<[string, boolean]> {
const {hsUrl, userId, hasAccessToken, isGuest} = await getStoredSessionVars();
return hsUrl && userId && hasAccessToken ? [userId, isGuest] : [null, null];
}
/**
@ -197,8 +191,8 @@ export function attemptTokenLogin(
},
).then(function(creds) {
console.log("Logged in with token");
return clearStorage().then(() => {
persistCredentialsToLocalStorage(creds);
return clearStorage().then(async () => {
await persistCredentials(creds);
// remember that we just logged in
sessionStorage.setItem("mx_fresh_login", String(true));
return true;
@ -276,24 +270,42 @@ function registerAsGuest(
});
}
export interface ILocalStorageSession {
export interface IStoredSession {
hsUrl: string;
isUrl: string;
accessToken: string;
hasAccessToken: boolean;
accessToken: string | object;
userId: string;
deviceId: string;
isGuest: boolean;
}
/**
* Retrieves information about the stored session in localstorage. The session
* Retrieves information about the stored session from the browser's storage. The session
* may not be valid, as it is not tested for consistency here.
* @returns {Object} Information about the session - see implementation for variables.
*/
export function getLocalStorageSessionVars(): ILocalStorageSession {
export async function getStoredSessionVars(): Promise<IStoredSession> {
const hsUrl = localStorage.getItem(HOMESERVER_URL_KEY);
const isUrl = localStorage.getItem(ID_SERVER_URL_KEY);
const accessToken = localStorage.getItem("mx_access_token");
let accessToken;
try {
accessToken = await StorageManager.idbLoad("account", "mx_access_token");
} catch (e) {}
if (!accessToken) {
accessToken = localStorage.getItem("mx_access_token");
if (accessToken) {
try {
// try to migrate access token to IndexedDB if we can
await StorageManager.idbSave("account", "mx_access_token", accessToken);
localStorage.removeItem("mx_access_token");
} catch (e) {}
}
}
// if we pre-date storing "mx_has_access_token", but we retrieved an access
// token, then we should say we have an access token
const hasAccessToken =
(localStorage.getItem("mx_has_access_token") === "true") || !!accessToken;
const userId = localStorage.getItem("mx_user_id");
const deviceId = localStorage.getItem("mx_device_id");
@ -305,7 +317,43 @@ export function getLocalStorageSessionVars(): ILocalStorageSession {
isGuest = localStorage.getItem("matrix-is-guest") === "true";
}
return {hsUrl, isUrl, accessToken, userId, deviceId, isGuest};
return {hsUrl, isUrl, hasAccessToken, accessToken, userId, deviceId, isGuest};
}
// The pickle key is a string of unspecified length and format. For AES, we
// need a 256-bit Uint8Array. So we HKDF the pickle key to generate the AES
// key. The AES key should be zeroed after it is used.
async function pickleKeyToAesKey(pickleKey: string): Promise<Uint8Array> {
const pickleKeyBuffer = new Uint8Array(pickleKey.length);
for (let i = 0; i < pickleKey.length; i++) {
pickleKeyBuffer[i] = pickleKey.charCodeAt(i);
}
const hkdfKey = await window.crypto.subtle.importKey(
"raw", pickleKeyBuffer, "HKDF", false, ["deriveBits"],
);
pickleKeyBuffer.fill(0);
return new Uint8Array(await window.crypto.subtle.deriveBits(
{
name: "HKDF", hash: "SHA-256",
// eslint-disable-next-line @typescript-eslint/ban-ts-comment
// @ts-ignore: https://github.com/microsoft/TypeScript-DOM-lib-generator/pull/879
salt: new Uint8Array(32), info: new Uint8Array(0),
},
hkdfKey,
256,
));
}
async function abortLogin() {
const signOut = await showStorageEvictedDialog();
if (signOut) {
await clearStorage();
// This error feels a bit clunky, but we want to make sure we don't go any
// further and instead head back to sign in.
throw new AbortLoginAndRebuildStorage(
"Aborting login in progress because of storage inconsistency",
);
}
}
// returns a promise which resolves to true if a session is found in
@ -325,7 +373,11 @@ async function restoreFromLocalStorage(opts?: { ignoreGuest?: boolean }): Promis
return false;
}
const {hsUrl, isUrl, accessToken, userId, deviceId, isGuest} = getLocalStorageSessionVars();
const {hsUrl, isUrl, hasAccessToken, accessToken, userId, deviceId, isGuest} = await getStoredSessionVars();
if (hasAccessToken && !accessToken) {
abortLogin();
}
if (accessToken && userId && hsUrl) {
if (ignoreGuest && isGuest) {
@ -333,9 +385,15 @@ async function restoreFromLocalStorage(opts?: { ignoreGuest?: boolean }): Promis
return false;
}
let decryptedAccessToken = accessToken;
const pickleKey = await PlatformPeg.get().getPickleKey(userId, deviceId);
if (pickleKey) {
console.log("Got pickle key");
if (typeof accessToken !== "string") {
const encrKey = await pickleKeyToAesKey(pickleKey);
decryptedAccessToken = await decryptAES(accessToken, encrKey, "access_token");
encrKey.fill(0);
}
} else {
console.log("No pickle key available");
}
@ -347,7 +405,7 @@ async function restoreFromLocalStorage(opts?: { ignoreGuest?: boolean }): Promis
await doSetLoggedIn({
userId: userId,
deviceId: deviceId,
accessToken: accessToken,
accessToken: decryptedAccessToken as string,
homeserverUrl: hsUrl,
identityServerUrl: isUrl,
guest: isGuest,
@ -486,15 +544,7 @@ async function doSetLoggedIn(
// crypto store, we'll be generally confused when handling encrypted data.
// Show a modal recommending a full reset of storage.
if (results.dataInLocalStorage && results.cryptoInited && !results.dataInCryptoStore) {
const signOut = await showStorageEvictedDialog();
if (signOut) {
await clearStorage();
// This error feels a bit clunky, but we want to make sure we don't go any
// further and instead head back to sign in.
throw new AbortLoginAndRebuildStorage(
"Aborting login in progress because of storage inconsistency",
);
}
await abortLogin();
}
Analytics.setLoggedIn(credentials.guest, credentials.homeserverUrl);
@ -516,7 +566,7 @@ async function doSetLoggedIn(
if (localStorage) {
try {
persistCredentialsToLocalStorage(credentials);
await persistCredentials(credentials);
// make sure we don't think that it's a fresh login any more
sessionStorage.removeItem("mx_fresh_login");
} catch (e) {
@ -545,18 +595,55 @@ function showStorageEvictedDialog(): Promise<boolean> {
// `instanceof`. Babel 7 supports this natively in their class handling.
class AbortLoginAndRebuildStorage extends Error { }
function persistCredentialsToLocalStorage(credentials: IMatrixClientCreds): void {
async function persistCredentials(credentials: IMatrixClientCreds): Promise<void> {
localStorage.setItem(HOMESERVER_URL_KEY, credentials.homeserverUrl);
if (credentials.identityServerUrl) {
localStorage.setItem(ID_SERVER_URL_KEY, credentials.identityServerUrl);
}
localStorage.setItem("mx_user_id", credentials.userId);
localStorage.setItem("mx_access_token", credentials.accessToken);
localStorage.setItem("mx_is_guest", JSON.stringify(credentials.guest));
// store whether we expect to find an access token, to detect the case
// where IndexedDB is blown away
if (credentials.accessToken) {
localStorage.setItem("mx_has_access_token", "true");
} else {
localStorage.deleteItem("mx_has_access_token");
}
if (credentials.pickleKey) {
let encryptedAccessToken;
try {
// try to encrypt the access token using the pickle key
const encrKey = await pickleKeyToAesKey(credentials.pickleKey);
encryptedAccessToken = await encryptAES(credentials.accessToken, encrKey, "access_token");
encrKey.fill(0);
} catch (e) {
console.warn("Could not encrypt access token", e);
}
try {
// save either the encrypted access token, or the plain access
// token if we were unable to encrypt (e.g. if the browser doesn't
// have WebCrypto).
await StorageManager.idbSave(
"account", "mx_access_token",
encryptedAccessToken || credentials.accessToken,
);
} catch (e) {
// if we couldn't save to indexedDB, fall back to localStorage. We
// store the access token unencrypted since localStorage only saves
// strings.
localStorage.setItem("mx_access_token", credentials.accessToken);
}
localStorage.setItem("mx_has_pickle_key", String(true));
} else {
try {
await StorageManager.idbSave(
"account", "mx_access_token", credentials.accessToken,
);
} catch (e) {
localStorage.setItem("mx_access_token", credentials.accessToken);
}
if (localStorage.getItem("mx_has_pickle_key")) {
console.error("Expected a pickle key, but none provided. Encryption may not work.");
}
@ -733,6 +820,10 @@ async function clearStorage(opts?: { deleteEverything?: boolean }): Promise<void
window.localStorage.clear();
try {
await StorageManager.idbDelete("account", "mx_access_token");
} catch (e) {}
// now restore those invites
if (!opts?.deleteEverything) {
pendingInvites.forEach(i => {

3
src/components/structures/auth/Registration.tsx
View file

@ -325,8 +325,7 @@ export default class Registration extends React.Component<IProps, IState> {
// isn't a guest user since we'll usually have set a guest user session before
// starting the registration process. This isn't perfect since it's possible
// the user had a separate guest session they didn't actually mean to replace.
const sessionOwner = Lifecycle.getStoredSessionOwner();
const sessionIsGuest = Lifecycle.getStoredSessionIsGuest();
const [sessionOwner, sessionIsGuest] = await Lifecycle.getStoredSessionOwner();
if (sessionOwner && !sessionIsGuest && sessionOwner !== response.userId) {
console.log(
`Found a session for ${sessionOwner} but ${response.userId} has just registered.`,

76
src/utils/StorageManager.js
View file

@ -190,3 +190,79 @@ export function trackStores(client) {
export function setCryptoInitialised(cryptoInited) {
localStorage.setItem("mx_crypto_initialised", cryptoInited);
}
/* Simple wrapper functions around IndexedDB.
*/
let idb = null;
async function idbInit(): Promise<void> {
if (!indexedDB) {
throw new Error("IndexedDB not available");
}
idb = await new Promise((resolve, reject) => {
const request = indexedDB.open("matrix-react-sdk", 1);
request.onerror = reject;
request.onsuccess = (event) => { resolve(request.result); };
request.onupgradeneeded = (event) => {
const db = request.result;
db.createObjectStore("pickleKey");
db.createObjectStore("account");
};
});
}
export async function idbLoad(
table: string,
key: string | string[],
): Promise<any> {
if (!idb) {
await idbInit();
}
return new Promise((resolve, reject) => {
const txn = idb.transaction([table], "readonly");
txn.onerror = reject;
const objectStore = txn.objectStore(table);
const request = objectStore.get(key);
request.onerror = reject;
request.onsuccess = (event) => { resolve(request.result); };
});
}
export async function idbSave(
table: string,
key: string | string[],
data: any,
): Promise<void> {
if (!idb) {
await idbInit();
}
return new Promise((resolve, reject) => {
const txn = idb.transaction([table], "readwrite");
txn.onerror = reject;
const objectStore = txn.objectStore(table);
const request = objectStore.put(data, key);
request.onerror = reject;
request.onsuccess = (event) => { resolve(); };
});
}
export async function idbDelete(
table: string,
key: string | string[],
): Promise<void> {
if (!idb) {
await idbInit();
}
return new Promise((resolve, reject) => {
const txn = idb.transaction([table], "readwrite");
txn.onerror = reject;
const objectStore = txn.objectStore(table);
const request = objectStore.delete(key);
request.onerror = reject;
request.onsuccess = (event) => { resolve(); };
});
}