Initial support for LDAP server authentication

Limitations as of this commit:

- tlsOptions can only be specified in config.json, not as env vars
- authentication failures are not yet gracefully handled by the UI
  - instead the error message is shown on a blank page (/auth/ldap)
- no email address is associated with the LDAP user's account
- no picture/profile URL is associated with the LDAP user's account
- we might have to generate our own access + refresh tokens,
  because we aren't using oauth. The currently generated
  tokens are just a placeholder.
- 'LDAP Sign in' needs to be translated to each locale

lib/auth.js

@@ -7,6 +7,7 @@ var GithubStrategy = require('passport-github').Strategy;
 var GitlabStrategy = require('passport-gitlab2').Strategy;
 var DropboxStrategy = require('passport-dropbox-oauth2').Strategy;
 var GoogleStrategy = require('passport-google-oauth20').Strategy;
+var LdapStrategy = require('passport-ldapauth');
 var LocalStrategy = require('passport-local').Strategy;
 var validator = require('validator');
 
@@ -110,6 +111,36 @@ if (config.google) {
         callbackURL: config.serverurl + '/auth/google/callback'
     }, callback));
 }
+// ldap
+if (config.ldap) {
+    passport.use(new LdapStrategy({
+        server: {
+            url: config.ldap.url || null,
+            bindDn: config.ldap.bindDn || null,
+            bindCredentials: config.ldap.bindCredentials || null,
+            searchBase: config.ldap.searchBase || null,
+            searchFilter: config.ldap.searchFilter || null,
+            searchAttributes: config.ldap.searchAttributes || null,
+            tlsOptions: config.ldap.tlsOptions || null
+        },
+    },
+    function(user, done) {
+        var profile = {
+            id: 'LDAP-' + user.uidNumber,
+            username: user.uid,
+            displayName: user.displayName,
+            emails: [],
+            avatarUrl: null,
+            profileUrl: null,
+            provider: 'ldap',
+        }
+        var stringifiedProfile = JSON.stringify(profile);
+        // TODO: Generate secure tokens for LDAP users
+        var accessToken = 'debug-access-token|LDAP-' + user.uidNumber + '|' + config.ldap.tokenSecret + '|' + new Date().getTime();
+        var refreshToken = 'debug-refresh-token|LDAP-' + user.uidNumber + '|' + config.ldap.tokenSecret + '|' + new Date().getTime();
+        callback(accessToken, refreshToken, profile, done);
+    }));
+}
 // email
 if (config.email) {
     passport.use(new LocalStrategy({
@@ -130,4 +161,4 @@ if (config.email) {
             return done(err);
         });
     }));
-}
+}