Failing EAP-TLS Authentication on Mobile Phones: A FreeRADIUS Solution for Automatically Connecting iPhones to Network

Introduction

In today's modern enterprise environments, secure and automatic network access is essential for mobile devices, especially iPhones. One of the most secure methods for authentication is EAP-TLS (Extensible Authentication Protocol - Transport Layer Security). EAP-TLS is a certificate-based authentication method that provides strong security. In this article, we will discuss how to set up EAP-TLS authentication with a RADIUS server and use Baramundi, an MDM (Mobile Device Management) solution, to deploy configuration certificates to automatically connect iPhones to the network.

Prerequisites

Before proceeding, ensure the following prerequisites are met:

A RADIUS server, such as FreeRADIUS, configured and running
A certificate authority (CA) to issue EAP-TLS certificates
An MDM solution, such as Baramundi, installed and configured

Configuring EAP-TLS on RADIUS Server

To configure EAP-TLS on the RADIUS server, follow these steps:

Generate a private key and a certificate signing request (CSR) on the RADIUS server:


 openssl req -newkey rsa:2048 -nodes -keyout radius.key -out radius.csr

Sign the CSR with your CA:


 openssl x509 -req -in radius.csr -signkey radius.key -out radius.crt

Configure the RADIUS server to use the EAP-TLS certificate:


 eap-radius 

 eap-radius {
 filename "/etc/freeradius/eap.conf";
 }
 

 eap {
 default EAP-TLS
 }
 

 eap-tls {
 certificate "/etc/freeradius/radius.crt";
 private_key "/etc/freeradius/radius.key";
 }

Configuring Baramundi to Deploy EAP-TLS Certificates

To configure Baramundi to deploy EAP-TLS certificates to iPhones, follow these steps:

Generate a certificate signing request (CSR) for the iPhone:


 openssl req -newkey rsa:2048 -nodes -keyout iPhone.key -out iPhone.csr