send/server/middleware/auth.js
2020-07-24 18:19:33 -07:00

79 lines
2.3 KiB
JavaScript

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);
}
}
};