Book Image

OpenVPN Cookbook - Second Edition

By : Jan Just Keijser
Book Image

OpenVPN Cookbook - Second Edition

By: Jan Just Keijser

Overview of this book

OpenVPN provides an extensible VPN framework that has been designed to ease site-specific customization, such as providing the capability to distribute a customized installation package to clients, and supporting alternative authentication methods via OpenVPN’s plugin module interface. This book provides you with many different recipes to help you set up, monitor, and troubleshoot an OpenVPN network. You will learn to configure a scalable, load-balanced VPN server farm that can handle thousands of dynamic connections from incoming VPN clients. You will also get to grips with the encryption, authentication, security, extensibility, and certifications features of OpenSSL. You will also get an understanding of IPv6 support and will get a demonstration of how to establish a connection via IPv64. This book will explore all the advanced features of OpenVPN and even some undocumented options, covering all the common network setups such as point-to-point networks and multi-client TUN-style and TAP-style networks. Finally, you will learn to manage, secure, and troubleshoot your virtual private networks using OpenVPN 2.4.
Table of Contents (17 chapters)
OpenVPN Cookbook - Second Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Using a tls-verify script


OpenVPN has several layers in which the credentials of a connecting client are verified. It is even possible to add a custom layer to the verification process by specifying a tls-verify script. In this recipe, we will demonstrate how such a script can be used to allow access only for a particular certificate.

Getting ready

Install OpenVPN 2.3 or higher on two computers. Make sure that the computers are connected over a network. Set up the client and server certificates using the Setting up the public and private keys recipe from Chapter 2Client-server IP-only Networks. For this recipe, the server computer was running Fedora 22 Linux and OpenVPN 2.3.10. The client was running Windows 7 64 bit and OpenVPN 2.3.10. For the client, keep the client configuration file, basic-udp-client.ovpn, from the Using an ifconfig-pool block recipe, from Chapter 2Client-server IP-only Networks .

How to do it...

  1. Create the server configuration file:

            proto udp 
            port...