Authenticate a Node application with LDAP

This post demonstrates how to authenticate a user against LDAP.

Let’s start by installing basic-auth and ldapauth-fork packages

npm install ldapauth-fork
npm install basic-auth

Steps for implementation;

Add packages
Create a ldap variable with authentication configuration
Basic auth should prompt for you username and password. Once user is found, verify the given password by trying to bind the user client with the found LDAP user object and given password.

const auth = require("basic-auth");
var LdapAuth = require("ldapauth-fork");

var ldap = new LdapAuth({
  url: "ldap://ldap-url:389",
  bindDN: "uid=rc,ou=AppAccounts,ou=People,ou=Entsys,dc=example.com",
  bindCredentials: "credentials",
  searchBase: "ou=entsys,dc=example.com",
  searchFilter: "(uid={{username}})",
  reconnect: true
});

app.use("/api/admin/", (req, res, next) => {
  const credentials = auth(req);
  if (credentials) {
    ldap.authenticate(credentials.name, credentials.pass, function(err, user) {
      if (err) {
        console.log(err.message);
        return res
          .status("401")
          .set({ "WWW-Authenticate": 'Basic realm="Access Denied"' })
          .end("access denied");
      }
      req.user = user;
      next();
    });
  } else {
    return res
      .status("401")
      .set({ "WWW-Authenticate": 'Basic realm="Access Denied"' })
      .end("access denied");
  }
});

Visit basic-auth, ldapauth-fork packages for more information on configuration.