gecko-dev/services/fxaccounts/Credentials.jsm

137 lines
4.4 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* This module implements client-side key stretching for use in Firefox
* Accounts account creation and login.
*
* See https://github.com/mozilla/fxa-auth-server/wiki/onepw-protocol
*/
"use strict";
this.EXPORTED_SYMBOLS = ["Credentials"];
const {utils: Cu, interfaces: Ci} = Components;
Cu.import("resource://gre/modules/Log.jsm");
Cu.import("resource://gre/modules/Services.jsm");
Cu.import("resource://gre/modules/Promise.jsm");
Cu.import("resource://services-crypto/utils.js");
Cu.import("resource://services-common/utils.js");
const PROTOCOL_VERSION = "identity.mozilla.com/picl/v1/";
const PBKDF2_ROUNDS = 1000;
const STRETCHED_PW_LENGTH_BYTES = 32;
const HKDF_SALT = CommonUtils.hexToBytes("00");
const HKDF_LENGTH = 32;
const HMAC_ALGORITHM = Ci.nsICryptoHMAC.SHA256;
const HMAC_LENGTH = 32;
// loglevel preference should be one of: "FATAL", "ERROR", "WARN", "INFO",
// "CONFIG", "DEBUG", "TRACE" or "ALL". We will be logging error messages by
// default.
const PREF_LOG_LEVEL = "identity.fxaccounts.loglevel";
try {
this.LOG_LEVEL =
Services.prefs.getPrefType(PREF_LOG_LEVEL) == Ci.nsIPrefBranch.PREF_STRING
&& Services.prefs.getCharPref(PREF_LOG_LEVEL);
} catch (e) {
this.LOG_LEVEL = Log.Level.Error;
}
var log = Log.repository.getLogger("Identity.FxAccounts");
log.level = LOG_LEVEL;
log.addAppender(new Log.ConsoleAppender(new Log.BasicFormatter()));
this.Credentials = Object.freeze({
/**
* Make constants accessible to tests
*/
constants: {
PROTOCOL_VERSION: PROTOCOL_VERSION,
PBKDF2_ROUNDS: PBKDF2_ROUNDS,
STRETCHED_PW_LENGTH_BYTES: STRETCHED_PW_LENGTH_BYTES,
HKDF_SALT: HKDF_SALT,
HKDF_LENGTH: HKDF_LENGTH,
HMAC_ALGORITHM: HMAC_ALGORITHM,
HMAC_LENGTH: HMAC_LENGTH,
},
/**
* KW function from https://github.com/mozilla/fxa-auth-server/wiki/onepw-protocol
*
* keyWord derivation for use as a salt.
*
*
* @param {String} context String for use in generating salt
*
* @return {bitArray} the salt
*
* Note that PROTOCOL_VERSION does not refer in any way to the version of the
* Firefox Accounts API.
*/
keyWord: function(context) {
return CommonUtils.stringToBytes(PROTOCOL_VERSION + context);
},
/**
* KWE function from https://github.com/mozilla/fxa-auth-server/wiki/onepw-protocol
*
* keyWord extended with a name and an email.
*
* @param {String} name The name of the salt
* @param {String} email The email of the user.
*
* @return {bitArray} the salt combination with the namespace
*
* Note that PROTOCOL_VERSION does not refer in any way to the version of the
* Firefox Accounts API.
*/
keyWordExtended: function(name, email) {
return CommonUtils.stringToBytes(PROTOCOL_VERSION + name + ':' + email);
},
setup: function(emailInput, passwordInput, options={}) {
let deferred = Promise.defer();
log.debug("setup credentials for " + emailInput);
let hkdfSalt = options.hkdfSalt || HKDF_SALT;
let hkdfLength = options.hkdfLength || HKDF_LENGTH;
let hmacLength = options.hmacLength || HMAC_LENGTH;
let hmacAlgorithm = options.hmacAlgorithm || HMAC_ALGORITHM;
let stretchedPWLength = options.stretchedPassLength || STRETCHED_PW_LENGTH_BYTES;
let pbkdf2Rounds = options.pbkdf2Rounds || PBKDF2_ROUNDS;
let result = {};
let password = CommonUtils.encodeUTF8(passwordInput);
let salt = this.keyWordExtended("quickStretch", emailInput);
let runnable = () => {
let start = Date.now();
let quickStretchedPW = CryptoUtils.pbkdf2Generate(
password, salt, pbkdf2Rounds, stretchedPWLength, hmacAlgorithm, hmacLength);
result.quickStretchedPW = quickStretchedPW;
result.authPW =
CryptoUtils.hkdf(quickStretchedPW, hkdfSalt, this.keyWord("authPW"), hkdfLength);
result.unwrapBKey =
CryptoUtils.hkdf(quickStretchedPW, hkdfSalt, this.keyWord("unwrapBkey"), hkdfLength);
log.debug("Credentials set up after " + (Date.now() - start) + " ms");
deferred.resolve(result);
}
Services.tm.currentThread.dispatch(runnable,
Ci.nsIThread.DISPATCH_NORMAL);
log.debug("Dispatched thread for credentials setup crypto work");
return deferred.promise;
}
});