NodeBB/NodeBB

'use strict';

const winston = require('winston');
const passport = require('passport');
const nconf = require('nconf');
const path = require('path');
const util = require('util');

const meta = require('../meta');
const user = require('../user');
const groups = require('../groups');
const topics = require('../topics');
const privileges = require('../privileges');
const privilegeHelpers = require('../privileges/helpers');
const plugins = require('../plugins');
const helpers = require('./helpers');
const auth = require('../routes/authentication');
const writeRouter = require('../routes/write');
const accountHelpers = require('../controllers/accounts/helpers');

const controllers = {
    helpers: require('../controllers/helpers'),
    authentication: require('../controllers/authentication'),
};

const passportAuthenticateAsync = function (req, res) {
    return new Promise((resolve, reject) => {
        passport.authenticate('core.api', (err, user) => {
            if (err) {
                reject(err);
            } else {
                resolve(user);
                res.on('finish', writeRouter.cleanup.bind(null, req));
            }
        })(req, res);
    });
};

module.exports = function (middleware) {
    async function authenticate(req, res) {
        async function finishLogin(req, user) {
            const loginAsync = util.promisify(req.login).bind(req);
            await loginAsync(user, { keepSessionInfo: true });
            await controllers.authentication.onSuccessfulLogin(req, user.uid);
            req.uid = parseInt(user.uid, 10);
            req.loggedIn = req.uid > 0;
            return true;
        }

        if (res.locals.isAPI && (req.loggedIn || !req.headers.hasOwnProperty('authorization'))) {
            // If authenticated via cookie (express-session), protect routes with CSRF checking
            await middleware.applyCSRFasync(req, res);
        }

        if (req.loggedIn) {
            return true;
        } else if (req.headers.hasOwnProperty('authorization')) {
            const user = await passportAuthenticateAsync(req, res);
            if (!user) { return true; }

            if (user.hasOwnProperty('uid')) {
                return await finishLogin(req, user);
            } else if (user.hasOwnProperty('master') && user.master === true) {
                // If the token received was a master token, a _uid must also be present for all calls
                if (req.body.hasOwnProperty('_uid') || req.query.hasOwnProperty('_uid')) {
                    user.uid = req.body._uid || req.query._uid;
                    delete user.master;
                    return await finishLogin(req, user);
                }

                throw new Error('[[error:api.master-token-no-uid]]');
            } else {
                winston.warn('[api/authenticate] Unable to find user after verifying token');
                return true;
            }
        }

        await plugins.hooks.fire('response:middleware.authenticate', {
            req: req,
            res: res,
            next: function () {}, // no-op for backwards compatibility
        });

        if (!res.headersSent) {
            auth.setAuthVars(req);
        }
        return !res.headersSent;
    }

    middleware.authenticateRequest = helpers.try(async (req, res, next) => {
        const { skip } = await plugins.hooks.fire('filter:middleware.authenticate', {
            skip: {
                // get: [],
                post: ['/api/v3/utilities/login'],
                // etc...
            },
        });

        const mountedPath = path.join(req.baseUrl, req.path).replace(nconf.get('relative_path'), '');
        const method = req.method.toLowerCase();
        if (skip[method] && skip[method].includes(mountedPath)) {
            return next();
        }

        if (!await authenticate(req, res)) {
            return;
        }
        next();
    });

    middleware.ensureSelfOrGlobalPrivilege = helpers.try(async (req, res, next) => {
        await ensureSelfOrMethod(user.isAdminOrGlobalMod, req, res, next);
    });

    middleware.ensureSelfOrPrivileged = helpers.try(async (req, res, next) => {
        await ensureSelfOrMethod(user.isPrivileged, req, res, next);
    });

    async function ensureSelfOrMethod(method, req, res, next) {
        /*
            The "self" part of this middleware hinges on you having used
            middleware.exposeUid prior to invoking this middleware.
        */
        if (!req.loggedIn) {
            return controllers.helpers.notAllowed(req, res);
        }
        if (req.uid === parseInt(res.locals.uid, 10)) {
            return next();
        }
        const allowed = await method(req.uid);
        if (!allowed) {
            return controllers.helpers.notAllowed(req, res);
        }

        return next();
    }

    middleware.canViewUsers = helpers.try(async (req, res, next) => {
        if (parseInt(res.locals.uid, 10) === req.uid) {
            return next();
        }
        const canView = await privileges.global.can('view:users', req.uid);
        if (canView) {
            return next();
        }
        controllers.helpers.notAllowed(req, res);
    });

    middleware.canViewGroups = helpers.try(async (req, res, next) => {
        const canView = await privileges.global.can('view:groups', req.uid);
        if (canView) {
            return next();
        }
        controllers.helpers.notAllowed(req, res);
    });

    middleware.canChat = helpers.try(async (req, res, next) => {
        const canChat = await privileges.global.can(['chat', 'chat:privileged'], req.uid);
        if (canChat.includes(true)) {
            return next();
        }
        controllers.helpers.notAllowed(req, res);
    });

    middleware.checkAccountPermissions = helpers.try(async (req, res, next) => {
        // This middleware ensures that only the requested user and admins can pass

        // This check if left behind for legacy purposes. Older plugins may call this middleware without ensureLoggedIn
        if (!req.loggedIn) {
            return controllers.helpers.notAllowed(req, res);
        }

        if (!['uid', 'userslug'].some(param => req.params.hasOwnProperty(param))) {
            return controllers.helpers.notAllowed(req, res);
        }

        const uid = req.params.uid || await user.getUidByUserslug(req.params.userslug);
        let allowed = await privileges.users.canEdit(req.uid, uid);
        if (allowed) {
            return next();
        }

        if (/user\/.+\/info$/.test(req.path)) {
            allowed = await privileges.global.can('view:users:info', req.uid);
        }
        if (allowed) {
            return next();
        }

        controllers.helpers.notAllowed(req, res);
    });

    middleware.redirectToAccountIfLoggedIn = helpers.try(async (req, res, next) => {
        if (req.session.forceLogin || req.uid <= 0) {
            return next();
        }
        const userslug = await user.getUserField(req.uid, 'userslug');
        controllers.helpers.redirect(res, `/user/${userslug}`);
    });

    middleware.redirectUidToUserslug = helpers.try(async (req, res, next) => {
        const uid = parseInt(req.params.uid, 10);
        if (uid <= 0) {
            return next();
        }
        const [canView, userslug] = await Promise.all([
            privileges.global.can('view:users', req.uid),
            user.getUserField(uid, 'userslug'),
        ]);

        if (!userslug || (!canView && req.uid !== uid)) {
            return next();
        }
        const path = req.url.replace(/^\/api/, '')
            .replace(`/uid/${uid}`, () => `/user/${userslug}`);
        controllers.helpers.redirect(res, path, true);
    });

    middleware.redirectMeToUserslug = helpers.try(async (req, res) => {
        const userslug = await user.getUserField(req.uid, 'userslug');
        if (!userslug) {
            return controllers.helpers.notAllowed(req, res);
        }
        const path = req.url.replace(/^(\/api)?\/me/, () => `/user/${userslug}`);
        controllers.helpers.redirect(res, path);
    });

    middleware.redirectToHomeIfBanned = helpers.try(async (req, res, next) => {
        if (req.loggedIn) {
            const canLoginIfBanned = await user.bans.canLoginIfBanned(req.uid);
            if (!canLoginIfBanned) {
                req.logout(() => {
                    res.redirect('/');
                });
                return;
            }
        }

        next();
    });

    middleware.requireUser = function (req, res, next) {
        if (req.loggedIn) {
            return next();
        }

        res.status(403).render('403', { title: '[[global:403.title]]' });
    };

    middleware.buildAccountData = async (req, res, next) => {
        res.locals.templateValues = await accountHelpers.getUserDataByUserSlug(req.params.userslug, req.uid, req.query);
        next();
    };

    middleware.registrationComplete = async function registrationComplete(req, res, next) {
        /**
         * Redirect the user to complete registration if:
         *   * user's session contains registration data
         *   * email is required and they have no confirmed email (pending doesn't count, but admins are OK)
         */
        const path = req.path.startsWith('/api/') ? req.path.replace('/api', '') : req.path;

        if (meta.config.requireEmailAddress && await requiresEmailConfirmation(req)) {
            req.session.registration = {
                ...req.session.registration,
                uid: req.uid,
                updateEmail: true,
            };
        }

        if (!req.session.hasOwnProperty('registration')) {
            return setImmediate(next);
        }

        const { allowed } = await plugins.hooks.fire('filter:middleware.registrationComplete', {
            allowed: ['/register/complete', '/confirm/'],
        });
        if (allowed.includes(path) || allowed.some(p => path.startsWith(p))) {
            return setImmediate(next);
        }

        // Append user data if present
        req.session.registration.uid = req.session.registration.uid || req.uid;

        controllers.helpers.redirect(res, '/register/complete');
    };

    async function requiresEmailConfirmation(req) {
        /**
         * N.B. THIS IS NOT AN AUTHENTICATION MECHANISM
         *
         * It merely decides whether or not the accessed category is restricted to
         * verified users only, and renders a decision (Boolean) based on whether
         * the calling user is verified or not.
         */
        if (req.uid <= 0) {
            return false;
        }

        // Extract tid or cid
        const [confirmed, isAdmin] = await Promise.all([
            groups.isMember(req.uid, 'verified-users'),
            user.isAdministrator(req.uid),
        ]);
        if (confirmed || isAdmin) {
            return false;
        }

        let cid;
        let privilege;
        if (req.params.hasOwnProperty('category_id')) {
            cid = req.params.category_id;
            privilege = 'read';
        } else if (req.params.hasOwnProperty('topic_id')) {
            cid = await topics.getTopicField(req.params.topic_id, 'cid');
            privilege = 'topics:read';
        } else {
            return false; // not a category or topic url, no check required
        }

        const [registeredAllowed, verifiedAllowed] = await Promise.all([
            privilegeHelpers.isAllowedTo([privilege], 'registered-users', cid),
            privilegeHelpers.isAllowedTo([privilege], 'verified-users', cid),
        ]);

        return !registeredAllowed.pop() && verifiedAllowed.pop();
    }
};