goldilocks.js/lib/ddns/challenge-responder.js

123 lines
4.0 KiB
JavaScript

'use strict';
// Much of this file was based on the `le-challenge-ddns` library (which we are not using
// here because it's method of setting records requires things we don't really want).
module.exports.create = function (deps, conf, utils) {
function getReleventSessionId(domain) {
var sessId;
utils.iterateAllModules(function (mod, domainList) {
// We return a truthy value in these cases because of the way the iterate function
// handles modules grouped by domain. By returning true we are saying these domains
// are "handled" and so if there are multiple modules we won't be given the rest.
if (sessId) { return true; }
if (domainList.indexOf(domain) < 0) { return true; }
// But if the domains are relevant but we don't know how to handle the module we
// return false to allow us to look at any other modules that might exist here.
if (mod.type !== 'dns@oauth3.org') { return false; }
sessId = mod.tokenId || mod.token_id;
return true;
});
return sessId;
}
function get(args, domain, challenge, done) {
done(new Error("Challenge.get() does not need an implementation for dns-01. (did you mean Challenge.loopback?)"));
}
// same as get, but external
function loopback(args, domain, challenge, done) {
var challengeDomain = (args.test || '') + args.acmeChallengeDns + domain;
require('dns').resolveTxt(challengeDomain, done);
}
var activeChallenges = {};
async function removeAsync(args, domain) {
var data = activeChallenges[domain];
if (!data) {
console.warn(new Error('cannot remove DNS challenge for ' + domain + ': already removed'));
return;
}
var session = await utils.getSession(data.sessId);
var directives = await deps.OAUTH3.discover(session.token.aud);
var apiOpts = {
api: 'dns.unset'
, session: session
, type: 'TXT'
, value: data.keyAuthDigest
};
await deps.OAUTH3.api(directives.api, Object.assign({}, apiOpts, data.splitDomain));
delete activeChallenges[domain];
}
async function setAsync(args, domain, challenge, keyAuth) {
if (activeChallenges[domain]) {
await removeAsync(args, domain, challenge);
}
var sessId = getReleventSessionId(domain);
if (!sessId) {
throw new Error('no DDNS module handles the domain ' + domain);
}
var session = await utils.getSession(sessId);
var directives = await deps.OAUTH3.discover(session.token.aud);
// I'm not sure what role challenge is supposed to play since even in the library
// this code is based on it was never used, but check for it anyway because ...
if (!challenge || keyAuth) {
console.warn(new Error('DDNS challenge missing challenge or keyAuth'));
}
var keyAuthDigest = require('crypto').createHash('sha256').update(keyAuth || '').digest('base64')
.replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/, '');
var challengeDomain = (args.test || '') + args.acmeChallengeDns + domain;
var splitDomain = (await utils.splitDomains(directives.api, [challengeDomain]))[0];
var apiOpts = {
api: 'dns.set'
, session: session
, type: 'TXT'
, value: keyAuthDigest
, ttl: args.ttl || 0
};
await deps.OAUTH3.api(directives.api, Object.assign({}, apiOpts, splitDomain));
activeChallenges[domain] = {
sessId
, keyAuthDigest
, splitDomain
};
return new Promise(res => setTimeout(res, 1000));
}
// It might be slightly easier to use arguments and apply, but the library that will use
// this function counts the arguments we expect.
function set(a, b, c, d, done) {
setAsync(a, b, c, d).then(result => done(null, result), done);
}
function remove(a, b, c, done) {
removeAsync(a, b, c).then(result => done(null, result), done);
}
function getOptions() {
return {
oauth3: 'oauth3.org'
, debug: conf.debug
, acmeChallengeDns: '_acme-challenge.'
};
}
return {
getOptions
, set
, get
, remove
, loopback
};
};