RocketChat/Rocket.Chat

import crypto from 'crypto';

import type { IUser, IMethodConnection } from '@rocket.chat/core-typings';
import { Users } from '@rocket.chat/models';
import { Accounts } from 'meteor/accounts-base';
import { Meteor } from 'meteor/meteor';

import { settings } from '../../../settings/server';
import { EmailCheck } from './EmailCheck';
import type { ICodeCheck } from './ICodeCheck';
import { PasswordCheckFallback } from './PasswordCheckFallback';
import { TOTPCheck } from './TOTPCheck';

export interface ITwoFactorOptions {
    disablePasswordFallback?: boolean;
    disableRememberMe?: boolean;
    requireSecondFactor?: boolean; // whether any two factor should be required
}

const totpCheck = new TOTPCheck();
export const emailCheck = new EmailCheck();
const passwordCheckFallback = new PasswordCheckFallback();

const checkMethods = new Map<string, ICodeCheck>();

checkMethods.set(totpCheck.name, totpCheck);
checkMethods.set(emailCheck.name, emailCheck);

function getMethodByNameOrFirstActiveForUser(user: IUser, name?: string): ICodeCheck | undefined {
    if (name && checkMethods.has(name)) {
        return checkMethods.get(name);
    }

    return Array.from(checkMethods.values()).find((method) => method.isEnabled(user));
}

function getAvailableMethodNames(user: IUser): string[] {
    return (
        Array.from(checkMethods)
            .filter(([, method]) => method.isEnabled(user))
            .map(([name]) => name) || []
    );
}

export async function getUserForCheck(userId: string): Promise<IUser | null> {
    return Users.findOneById(userId, {
        projection: {
            'emails': 1,
            'language': 1,
            'createdAt': 1,
            'services.totp': 1,
            'services.email2fa': 1,
            'services.emailCode': 1,
            'services.password': 1,
            'services.resume.loginTokens': 1,
        },
    });
}

function getFingerprintFromConnection(connection: IMethodConnection): string {
    const data = JSON.stringify({
        userAgent: connection.httpHeaders['user-agent'],
        clientAddress: connection.clientAddress,
    });

    return crypto.createHash('md5').update(data).digest('hex');
}

function getRememberDate(from: Date = new Date()): Date | undefined {
    const rememberFor = parseInt(settings.get('Accounts_TwoFactorAuthentication_RememberFor') as string, 10);

    if (rememberFor <= 0) {
        return;
    }

    const expires = new Date(from);
    expires.setSeconds(expires.getSeconds() + rememberFor);

    return expires;
}

function isAuthorizedForToken(connection: IMethodConnection, user: IUser, options: ITwoFactorOptions): boolean {
    const currentToken = Accounts._getLoginToken(connection.id);
    const tokenObject = user.services?.resume?.loginTokens?.find((i) => i.hashedToken === currentToken);

    if (!tokenObject) {
        return false;
    }

    // if any two factor is required, early abort
    if (options.requireSecondFactor) {
        return false;
    }

    if ('bypassTwoFactor' in tokenObject && tokenObject.bypassTwoFactor === true) {
        return true;
    }

    if (options.disableRememberMe === true) {
        return false;
    }

    // remember user right after their registration
    const rememberAfterRegistration = user.createdAt && getRememberDate(user.createdAt);
    if (rememberAfterRegistration && rememberAfterRegistration >= new Date()) {
        return true;
    }

    if (!tokenObject.twoFactorAuthorizedUntil || !tokenObject.twoFactorAuthorizedHash) {
        return false;
    }

    if (tokenObject.twoFactorAuthorizedUntil < new Date()) {
        return false;
    }

    if (tokenObject.twoFactorAuthorizedHash !== getFingerprintFromConnection(connection)) {
        return false;
    }

    return true;
}

async function rememberAuthorization(connection: IMethodConnection, user: IUser): Promise<void> {
    const currentToken = Accounts._getLoginToken(connection.id);

    const expires = getRememberDate();
    if (!expires) {
        return;
    }

    if (!currentToken) {
        return;
    }

    await Users.setTwoFactorAuthorizationHashAndUntilForUserIdAndToken(
        user._id,
        currentToken,
        getFingerprintFromConnection(connection),
        expires,
    );
}

interface ICheckCodeForUser {
    user: IUser | string;
    code?: string;
    method?: string;
    options?: ITwoFactorOptions;
    connection?: IMethodConnection;
}

const getSecondFactorMethod = (user: IUser, method: string | undefined, options: ITwoFactorOptions): ICodeCheck | undefined => {
    // try first getting one of the available methods or the one that was already provided
    const selectedMethod = getMethodByNameOrFirstActiveForUser(user, method);
    if (selectedMethod) {
        return selectedMethod;
    }

    // if none found but a second factor is required, chose the password check
    if (options.requireSecondFactor) {
        return passwordCheckFallback;
    }

    // check if password fallback is enabled
    if (!options.disablePasswordFallback && passwordCheckFallback.isEnabled(user, !!options.requireSecondFactor)) {
        return passwordCheckFallback;
    }
};

export async function checkCodeForUser({ user, code, method, options = {}, connection }: ICheckCodeForUser): Promise<boolean> {
    if (process.env.TEST_MODE && !options.requireSecondFactor) {
        return true;
    }

    if (!settings.get('Accounts_TwoFactorAuthentication_Enabled')) {
        return true;
    }

    let existingUser: IUser | null;

    if (typeof user === 'string') {
        existingUser = await getUserForCheck(user);
    } else {
        existingUser = user;
    }

    if (!existingUser) {
        throw new Meteor.Error('totp-user-not-found', 'TOTP User not found');
    }

    if (!code && !method && connection?.httpHeaders?.['x-2fa-code'] && connection.httpHeaders['x-2fa-method']) {
        code = connection.httpHeaders['x-2fa-code'];
        method = connection.httpHeaders['x-2fa-method'];
    }

    if (connection && isAuthorizedForToken(connection, existingUser, options)) {
        return true;
    }

    // select a second factor method or return if none is found/available
    const selectedMethod = getSecondFactorMethod(existingUser, method, options);
    if (!selectedMethod) {
        return true;
    }

    const data = await selectedMethod.processInvalidCode(existingUser);

    const availableMethods = getAvailableMethodNames(existingUser);

    if (!code) {
        throw new Meteor.Error('totp-required', 'TOTP Required', {
            method: selectedMethod.name,
            ...data,
            availableMethods,
        });
    }

    const valid = await selectedMethod.verify(existingUser, code, options.requireSecondFactor);
    if (!valid) {
        const tooManyFailedAttempts = await selectedMethod.maxFaildedAttemtpsReached(existingUser);
        if (tooManyFailedAttempts) {
            throw new Meteor.Error('totp-max-attempts', 'TOTP Maximun Failed Attempts Reached', {
                method: selectedMethod.name,
                ...data,
                availableMethods,
            });
        }

        throw new Meteor.Error('totp-invalid', 'TOTP Invalid', {
            method: selectedMethod.name,
            ...data,
            availableMethods,
        });
    }

    if (options.disableRememberMe !== true && connection) {
        await rememberAuthorization(connection, existingUser);
    }

    return true;
}