const assert = require('assert'); const crypto = require('crypto'); const storage = require('../storage'); const fxa = require('../fxa'); module.exports = { hmac: async function(req, res, next) { const id = req.params.id; const authHeader = req.header('Authorization'); if (id && authHeader) { try { const auth = req.header('Authorization').split(' ')[1]; const meta = await storage.metadata(id); if (!meta) { return res.sendStatus(404); } const hmac = crypto.createHmac( 'sha256', Buffer.from(meta.auth, 'base64') ); hmac.update(Buffer.from(meta.nonce, 'base64')); const verifyHash = hmac.digest(); if (crypto.timingSafeEqual(verifyHash, Buffer.from(auth, 'base64'))) { req.nonce = crypto.randomBytes(16).toString('base64'); storage.setField(id, 'nonce', req.nonce); res.set('WWW-Authenticate', `send-v1 ${req.nonce}`); req.authorized = true; req.meta = meta; } else { res.set('WWW-Authenticate', `send-v1 ${meta.nonce}`); req.authorized = false; } } catch (e) { req.authorized = false; } } if (req.authorized) { next(); } else { res.sendStatus(401); } }, owner: async function(req, res, next) { const id = req.params.id; const ownerToken = req.body.owner_token; if (id && ownerToken) { try { req.meta = await storage.metadata(id); if (!req.meta || req.meta.dead) { return res.sendStatus(404); } const metaOwner = Buffer.from(req.meta.owner, 'utf8'); const owner = Buffer.from(ownerToken, 'utf8'); assert(metaOwner.length > 0); assert(metaOwner.length === owner.length); req.authorized = crypto.timingSafeEqual(metaOwner, owner); } catch (e) { req.authorized = false; } } if (req.authorized) { next(); } else { res.sendStatus(401); } }, fxa: async function(req, res, next) { const authHeader = req.header('Authorization'); if (authHeader && /^Bearer\s/i.test(authHeader)) { const token = authHeader.split(' ')[1]; req.user = await fxa.verify(token); } if (req.user) { next(); } else { res.sendStatus(401); } }, dlToken: async function(req, res, next) { const authHeader = req.header('Authorization'); if (authHeader && /^Bearer\s/i.test(authHeader)) { const token = authHeader.split(' ')[1]; const id = req.params.id; req.meta = await storage.metadata(id); if (!req.meta || req.meta.dead) { return res.sendStatus(404); } req.authorized = await req.meta.verifyDownloadToken(token); } if (req.authorized) { next(); } else { res.sendStatus(401); } } };