implemented setting DNS records after tunnel connect

currently done automatically by API we get the tunnel token from, but in the
near-ish future that will be changed

lib/ddns/dns-ctrl.js

@@ -98,12 +98,20 @@ module.exports.create = function (deps, conf) {
       return domains.indexOf(record.host) !== -1;
     });
 
-    var oldDomains = ourDns.filter(function (record) {
+    // Of all the DNS records referring to our device and the current list of domains determine
+    // which domains have records with outdated address, and which ones we can just leave be
+    // without updating them.
+    var badAddrDomains = ourDns.filter(function (record) {
       return record.value !== addr;
-    }).map(function (record) {
+    }).map(record => record.host);
-      return record.host;
+    var goodAddrDomains = ourDns.filter(function (record) {
+      return record.value === addr && badAddrDomains.indexOf(record.host) < 0;
+    }).map(record => record.host);
+    var requiredUpdates = domains.filter(function (domain) {
+      return goodAddrDomains.indexOf(domain) !== -1;
     });
-    var oldDns = await splitDomains(directives.api, oldDomains);
+
+    var oldDns = await splitDomains(directives.api, badAddrDomains);
     var common = {
       api: 'devices.detach'
     , session: session
@@ -113,7 +121,7 @@ module.exports.create = function (deps, conf) {
       return deps.OAUTH3.api(directives.api, Object.assign({}, common, record));
     }));
 
-    var newDns = await splitDomains(directives.api, domains);
+    var newDns = await splitDomains(directives.api, requiredUpdates);
     common = {
       api: 'devices.attach'
     , session: session

lib/ddns/index.js

@@ -1,6 +1,7 @@
 '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);
@@ -40,7 +41,31 @@ module.exports.create = function (deps, conf) {
   }
 
   var tunnelActive = false;
-  async function connectTunnel() {
+  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
@@ -48,20 +73,15 @@ module.exports.create = function (deps, conf) {
       tunnelSession = await deps.storage.tokens.get(conf.ddns.tunnel.tokenId);
     }
 
-    await iterateAllModules(function startTunnel(mod, domainList) {
+    await iterateAllModules(function (mod, domainList) {
       if (mod.type !== 'dns@oauth3.org') { return null; }
 
-      return getSession(mod.tokenId).then(function (dnsSession) {
+      return startTunnel(tunnelSession, mod, domainList);
-        return deps.tunnelClients.start(tunnelSession || dnsSession, domainList);
-      }).catch(function (err) {
-        console.log('error starting tunnel for', domainList.join(', '));
-        console.log(err);
-      });
     });
 
     tunnelActive = true;
   }
-  async function disconnectTunnel() {
+  async function disconnectTunnels() {
     deps.tunnelClients.disconnect();
     tunnelActive = false;
     await Promise.resolve();
@@ -94,13 +114,8 @@ module.exports.create = function (deps, conf) {
       tunnelSession = await deps.storage.tokens.get(conf.ddns.tunnel.tokenId);
     }
 
-    await Promise.all(newTokens.map(function startTunnel({mod, domainList}) {
+    await Promise.all(newTokens.map(function ({mod, domainList}) {
-      return getSession(mod.tokenId).then(function (dnsSession) {
+      return startTunnel(tunnelSession, mod, domainList);
-        return deps.tunnelClients.start(tunnelSession || dnsSession, domainList);
-      }).catch(function (err) {
-        console.log('error starting tunnel for', domainList.join(', '));
-        console.log(err);
-      });
     }));
   }
 
@@ -131,11 +146,11 @@ module.exports.create = function (deps, conf) {
     // address. Otherwise we need to use the tunnel to accept traffic.
     if (!notLooped.length) {
       if (tunnelActive) {
-        await disconnectTunnel();
+        await disconnectTunnels();
       }
     } else {
       if (!tunnelActive) {
-        await connectTunnel();
+        await connectAllTunnels();
       }
     }
   }
@@ -285,7 +300,7 @@ module.exports.create = function (deps, conf) {
       if (equal(curConf.ddns.tunnel, conf.ddns.tunnel)) {
         return checkTunnelTokens();
       } else {
-        return disconnectTunnel().then(connectTunnel);
+        return disconnectTunnels().then(connectAllTunnels);
       }
     }).catch(function (err) {
       console.error('error transitioning DNS between configurations');

lib/tunnel-client-manager.js

@@ -92,6 +92,10 @@ module.exports.create = function (deps, config) {
     // to keep record of what domains we are handling and what tunnel server
     // those domains should go to.
     activeDomains[data.domains] = data;
+
+    // This is mostly for the start, but return the host for the tunnel server
+    // we've connected to (after stripping the protocol and path away).
+    return data.tunnelUrl.replace(/^[a-z]*:\/\//i, '').replace(/\/.*/, '');
   }
 
   async function acquireToken(session, domains) {
@@ -118,7 +122,7 @@ module.exports.create = function (deps, config) {
 
     var directives = await OAUTH3.discover(session.token.aud);
     var tokenData = await OAUTH3.api(directives.api, opts);
-    await addToken(tokenData);
+    return addToken(tokenData);
   }
 
   function disconnectAll() {