goldilocks.js/lib/ddns/index.js

335 lines
11 KiB
JavaScript

'use strict';
module.exports.create = function (deps, conf) {
var dns = deps.PromiseA.promisifyAll(require('dns'));
var network = deps.PromiseA.promisifyAll(deps.recase.camelCopy(require('network')));
var loopback = require('./loopback').create(deps, conf);
var dnsCtrl = require('./dns-ctrl').create(deps, conf);
var equal = require('deep-equal');
var loopbackDomain;
function iterateAllModules(action, curConf) {
curConf = curConf || conf;
var promises = curConf.ddns.modules.map(function (mod) {
return action(mod, mod.domains);
});
curConf.domains.forEach(function (dom) {
if (!dom.modules || !Array.isArray(dom.modules.ddns) || !dom.modules.ddns.length) {
return null;
}
// For the time being all of our things should only be tried once (regardless if it succeeded)
// TODO: revisit this behavior when we support multiple ways of setting records, and/or
// if we want to allow later modules to run if early modules fail.
promises.push(dom.modules.ddns.reduce(function (prom, mod) {
if (prom) { return prom; }
return action(mod, dom.names);
}, null));
});
return deps.PromiseA.all(promises.filter(Boolean));
}
async function getSession(id) {
var session = await deps.storage.tokens.get(id);
if (!session) {
throw new Error('no user token with ID "'+id+'"');
}
return session;
}
var tunnelActive = false;
async function startTunnel(tunnelSession, mod, domainList) {
try {
var dnsSession = await getSession(mod.tokenId);
var tunnelDomain = await deps.tunnelClients.start(tunnelSession || dnsSession, domainList);
var addrList;
try {
addrList = await dns.resolve4Async(tunnelDomain);
} catch (e) {}
if (!addrList || !addrList.length) {
try {
addrList = await dns.resolve6Async(tunnelDomain);
} catch (e) {}
}
if (!addrList || !addrList.length || !addrList[0]) {
throw new Error('failed to lookup IP for tunnel domain "' + tunnelDomain + '"');
}
await dnsCtrl.setDeviceAddress(dnsSession, addrList[0], domainList);
} catch (err) {
console.log('error starting tunnel for', domainList.join(', '));
console.log(err);
}
}
async function connectAllTunnels() {
var tunnelSession;
if (conf.ddns.tunnel) {
// In the case of a non-existant token, I'm not sure if we want to throw here and prevent
// any tunnel connections, or if we want to ignore it and fall back to the DNS tokens
tunnelSession = await deps.storage.tokens.get(conf.ddns.tunnel.tokenId);
}
await iterateAllModules(function (mod, domainList) {
if (mod.type !== 'dns@oauth3.org') { return null; }
return startTunnel(tunnelSession, mod, domainList);
});
tunnelActive = true;
}
async function disconnectTunnels() {
deps.tunnelClients.disconnect();
tunnelActive = false;
await Promise.resolve();
}
async function checkTunnelTokens() {
var oldTokens = deps.tunnelClients.current();
var newTokens = await iterateAllModules(function checkTokens(mod, domainList) {
if (mod.type !== 'dns@oauth3.org') { return null; }
var domainStr = domainList.slice().sort().join(',');
// If there is already a token handling exactly the domains this modules
// needs handled remove it from the list of tokens to be removed. Otherwise
// return the module and domain list so we can get new tokens.
if (oldTokens[domainStr]) {
delete oldTokens[domainStr];
} else {
return Promise.resolve({ mod, domainList });
}
});
await Promise.all(Object.values(oldTokens).map(deps.tunnelClients.remove));
if (!newTokens.length) { return; }
var tunnelSession;
if (conf.ddns.tunnel) {
// In the case of a non-existant token, I'm not sure if we want to throw here and prevent
// any tunnel connections, or if we want to ignore it and fall back to the DNS tokens
tunnelSession = await deps.storage.tokens.get(conf.ddns.tunnel.tokenId);
}
await Promise.all(newTokens.map(function ({mod, domainList}) {
return startTunnel(tunnelSession, mod, domainList);
}));
}
var localAddr, gateway;
async function checkNetworkEnv() {
// Since we can't detect the OS level events when a user plugs in an ethernet cable to recheck
// what network environment we are in we check our local network address and the gateway to
// determine if we need to run the loopback check and router configuration again.
var gw = await network.getGatewayIpAsync();
var addr = await network.getPrivateIpAsync();
if (localAddr === addr && gateway === gw) {
return;
}
var loopResult = await loopback(loopbackDomain);
var notLooped = Object.keys(loopResult.ports).filter(function (port) {
return !loopResult.ports[port];
});
// if (notLooped.length) {
// // TODO: try to automatically configure router to forward ports to us.
// }
// If we are on a public address or all ports we are listening on are forwarded to us then
// we don't need the tunnel and we can set the DNS records for all our domains to our public
// address. Otherwise we need to use the tunnel to accept traffic.
if (!notLooped.length) {
if (tunnelActive) {
await disconnectTunnels();
}
} else {
if (!tunnelActive) {
await connectAllTunnels();
}
}
// Don't assign these until the end of the function. This means that if something failed
// in the loopback or tunnel connection that we will try to go through the whole process
// again next time and hopefully the error is temporary (but if not I'm not sure what the
// correct course of action would be anyway).
localAddr = addr;
gateway = gw;
}
var publicAddress;
async function recheckPubAddr() {
await checkNetworkEnv();
if (tunnelActive) {
return;
}
var addr = await loopback.checkPublicAddr(loopbackDomain);
if (publicAddress === addr) {
return;
}
if (conf.debug) {
console.log('previous public address',publicAddress, 'does not match current public address', addr);
}
publicAddress = addr;
await iterateAllModules(function setModuleDNS(mod, domainList) {
if (mod.type !== 'dns@oauth3.org' || mod.disabled) { return null; }
return getSession(mod.tokenId).then(function (session) {
return dnsCtrl.setDeviceAddress(session, addr, domainList);
}).catch(function (err) {
console.log('error setting DNS records for', domainList.join(', '));
console.log(err);
});
});
}
function getModuleDiffs(prevConf) {
var prevMods = {};
var curMods = {};
// this returns a Promise, but since the functions we use are synchronous
// and change our enclosed variables we don't need to wait for the return.
iterateAllModules(function (mod, domainList) {
if (mod.type !== 'dns@oauth3.org') { return; }
prevMods[mod.id] = { mod, domainList };
return true;
}, prevConf);
iterateAllModules(function (mod, domainList) {
if (mod.type !== 'dns@oauth3.org') { return; }
curMods[mod.id] = { mod, domainList };
return true;
});
// Filter out all of the modules that are exactly the same including domainList
// since there is no required action to transition.
Object.keys(prevMods).map(function (id) {
if (equal(prevMods[id], curMods[id])) {
delete prevMods[id];
delete curMods[id];
}
});
return {prevMods, curMods};
}
async function cleanOldDns(prevConf) {
var {prevMods, curMods} = getModuleDiffs(prevConf);
// Then remove DNS records for the domains that we are no longer responsible for.
await Promise.all(Object.values(prevMods).map(function ({mod, domainList}) {
var oldDomains;
if (!curMods[mod.id] || mod.tokenId !== curMods[mod.id].mod.tokenId) {
oldDomains = domainList.slice();
} else {
oldDomains = domainList.filter(function (domain) {
return curMods[mod.id].domainList.indexOf(domain) < 0;
});
}
if (conf.debug) {
console.log('removing old domains for module', mod.id, oldDomains.join(', '));
}
if (!oldDomains.length) {
return;
}
return getSession(mod.tokenId).then(function (session) {
return dnsCtrl.removeDomains(session, oldDomains);
});
}).filter(Boolean));
}
async function setNewDns(prevConf) {
var {prevMods, curMods} = getModuleDiffs(prevConf);
// And add DNS records for any newly added domains.
await Promise.all(Object.values(curMods).map(function ({mod, domainList}) {
var newDomains;
if (!prevMods[mod.id] || mod.tokenId !== prevMods[mod.id].mod.tokenId) {
newDomains = domainList.slice();
} else {
newDomains = domainList.filter(function (domain) {
return prevMods[mod.id].domainList.indexOf(domain) < 0;
});
}
if (conf.debug) {
console.log('adding new domains for module', mod.id, newDomains.join(', '));
}
if (!newDomains.length) {
return;
}
return getSession(mod.tokenId).then(function (session) {
return dnsCtrl.setDeviceAddress(session, publicAddress, newDomains);
});
}).filter(Boolean));
}
function check() {
recheckPubAddr().catch(function (err) {
console.error('failed to handle all actions needed for DDNS');
console.error(err);
});
}
check();
setInterval(check, 5*60*1000);
var curConf;
function updateConf() {
if (curConf && equal(curConf.ddns, conf.ddns) && equal(curConf.domains, conf.domains)) {
// We could update curConf, but since everything we care about is the same...
return;
}
if (!curConf || !equal(curConf.ddns.loopback, conf.ddns.loopback)) {
loopbackDomain = 'oauth3.org';
if (conf.ddns && conf.ddns.loopback) {
if (conf.ddns.loopback.type === 'tunnel@oauth3.org' && conf.ddns.loopback.domain) {
loopbackDomain = conf.ddns.loopback.domain;
} else {
console.error('invalid loopback configuration: bad type or missing domain');
}
}
}
if (!curConf) {
// We need to make a deep copy of the config so we can use it next time to
// compare and see what setup/cleanup is needed to adapt to the changes.
curConf = JSON.parse(JSON.stringify(conf));
return;
}
cleanOldDns(curConf).then(function () {
if (!tunnelActive) {
return setNewDns(curConf);
}
if (equal(curConf.ddns.tunnel, conf.ddns.tunnel)) {
return checkTunnelTokens();
} else {
return disconnectTunnels().then(connectAllTunnels);
}
}).catch(function (err) {
console.error('error transitioning DNS between configurations');
console.error(err);
}).then(function () {
// We need to make a deep copy of the config so we can use it next time to
// compare and see what setup/cleanup is needed to adapt to the changes.
curConf = JSON.parse(JSON.stringify(conf));
});
}
updateConf();
return {
loopbackServer: loopback.server
, setDeviceAddress: dnsCtrl.setDeviceAddress
, getDeviceAddresses: dnsCtrl.getDeviceAddresses
, recheckPubAddr: recheckPubAddr
, updateConf: updateConf
};
};