Firebox Mobile VPN with L2TP Integration with AuthPoint

Deployment Overview

This document describes how to set up AuthPoint multi-factor authentication (MFA) for Active Directory users that use Mobile VPN with L2TP.

If the L2TP VPN client is only used by local AuthPoint users, you do not have to configure Microsoft NPS or enable MS–CHAPv2. NPS is only required for users synced from Active Directory or an LDAP database.

Your Firebox must already be configured and deployed before you set up MFA with AuthPoint.

AuthPoint supports RADIUS authentication with PAP and MS-CHAPv2. 802.1x authentication is not supported.

Users synced from Azure AD cannot authenticate to RADIUS client resources that use MS-CHAPv2.

Integration Summary

The hardware and software used in this guide include:

  • Firebox with Fireware v12.5.3 or higher
  • AuthPoint Gateway v5.3.1.184 or higher
  • Windows Server 2016 with Microsoft Network Policy Server (NPS) and Active Directory Domain Services

WatchGuard Firebox Authentication Data Flow with AuthPoint

AuthPoint communicates with various cloud-based services and service providers with the RADIUS protocol. This diagram shows the data flow of an MFA transaction for the Mobile VPN with L2TP client.

The topology for this integration.

Before You Begin

Before you begin these procedures, make sure that:

  • You have installed and configured the v5.3.1 or higher of the AuthPoint Gateway (see About Gateways)
  • You have installed and configured Active Directory Domain Services
  • You have installed Network Policy and Access Services, which includes Network Policy Server (NPS)

Configure Microsoft NPS Server

To enable users synced from Active Directory to successfully authenticate with MS-CHAPv2, you must configure Microsoft Network Policy Server (NPS). NPS is required to validate the user credentials from MS-CHAPv2 RADIUS requests against Active Directory.

For instructions to configure Active Directory Domain Services, see the Microsoft documentation for Active Directory.

If the L2TP VPN client is only used by local AuthPoint users, you do not have to configure Microsoft NPS. Continue to the Configure the Firebox section.

  1. On the Windows server, run Server Manager.
  2. Select Tools > Network Policy Server.
    The Network Policy Server console appears.
  3. Select RADIUS Clients and Servers > RADIUS Clients.
  4. Right-click RADIUS Clients and select New.
    The New RADIUS Client window appears.
  5. In the Friendly name text box, type a name.
  6. In the Address (IP or DNS) text box, type the IP address of the AuthPoint Gateway. In our example, the IP address of the AuthPoint Gateway is 192.168.100.20.
  7. In the Shared secret and Confirm shared secret text boxes, type a shared secret key. This key is used to communicate with the RADIUS server (AuthPoint Gateway).

    You must use the same shared secret key when you configure your Firebox in the Configure the Firebox section and your RADIUS client resource in the Add a RADIUS Client Resource in AuthPoint section.

  8. Click OK.
  9. Select Polices > Connection Request Policies. Make sure the default policy is enabled.
  10. Right-click Network Policies and select New.
    The New Network Policy window appears.
  11. In the Policy Name text box, type a name for this policy. In our example, we type ecotest.
  12. Click Next.
  13. In the Specify Conditions section, click Add.
  14. Select User Groups. Click Add > Add Groups.
  15. In the Enter the object name to select text box, type the group name. The name of this group must match the name of the Active Directory group your users belong to.
  16. Click OK.
  17. Click OK.
  18. Click Next.
  19. Click Next.
  20. In the Configure Authentication Methods section, clear the User can change password after it has expired check box.
  21. Click Next.
  22. Click Next.
  23. In the Configure Settings section, click Add. In our example we use group authentication. If you want to use user authentication, skip Steps 23-29.
  24. From the Attributes list, select Filter-Id. Click Add.
  25. Click Add.
  26. In the Attribute Information window, type a group name in the text box. The name of this group must match the name of the Active Directory group your users belong to.
  27. Click OK.
  28. Click OK.
  29. Click Close.
  30. Click Next.
  31. Click Finish.
  32. Right-click NPS (Local) and select Register server in Active Directory.
  33. Click OK.
  34. Click OK.

Configure the Firebox

You must configure the RADIUS authentication settings and enable Mobile VPN with L2TP on your Firebox.

Configure RADIUS Authentication

When a user authenticates with AuthPoint MFA, AuthPoint does not send a response to the Firebox until the user approves the push notification that is sent to them or until the push authentication expires.

When you configure the RADIUS authentication server, the timeout value must be greater than the combined push timeout for AuthPoint (60 seconds) and NPS (30 seconds). With the default settings on RADIUS authentication server, if a user does not approve the push notification that is sent to them within 30 seconds (3 tries, 10 seconds each), the Firebox will fail over to another server, even though the current server is not down.

  1. Log in to Fireware Web UI (https://<your firebox IP address>:8080).
  2. Select Authentication > Servers.
    The Authentication Servers page appears.

    Screenshot of the Authentication Servers page.

  3. From the Authentication Servers list, click RADIUS.
    The RADIUS page appears.
  4. Click Add.
    The Add page appears.
  5. In the Domain Name text box, type a name for this RADIUS server. Users must specify this domain name on the user login page. You cannot change the domain name after you save the settings.
  6. In the Primary Server Settings section, select the Enable RADIUS Server check box.
  7. In the IP Address text box, type the IP address of the RADIUS server (AuthPoint Gateway). In our example, the IP address of the AuthPoint Gateway is 192.168.100.20.
  8. In the Port text box, leave the default port setting of 1812. This is the default port used for communication with the RADIUS server (AuthPoint Gateway).

    If you already have a RADIUS server installed that uses port 1812, or if NPS and the Gateway are installed on the same server, you must use a different port for the AuthPoint Gateway.

  9. In the Shared Secret and Confirm Secret text boxes, type the shared secret key that you specified in the Configure Microsoft NPS Server section. This is the password that the RADIUS server (AuthPoint Gateway) and the RADIUS client (Firebox) will use to communicate.
  10. In the Timeout text box, type 90.
  11. Leave the default value for Group Attribute.
  12. This screenshot shows the RADIUS authentication server settings.

  13. Click Save.

Configure Mobile VPN with L2TP

  1. Select VPN > Mobile VPN.
  2. In the L2TP section, click Manually Configure.
  3. This screenshot shows the Mobile VPN page.

  4. Select the Activate Mobile VPN with L2TP check box.
  5. Select the Authentication tab.
  6. In the Authentication Server section, from the drop-down list, select the authentication server you created. Click Add.
  7. To make your authentication server the default authentication server, in the Authentication Server list, select your authentication server and click Move Up to move it to the top of the list.
    Mobile VPN with L2TP uses the default authentication server unless a user specifies an authentication server as part of the user name when they authenticate from an L2TP client.

    If you have an L2TP VPN client configured and you only want to test AuthPoint MFA, do not make your authentication server the default.

  8. In the Users and Groups section, from the Create new drop-down list, select the authentication server you created.
  9. From the adjacent drop-down list, select Group.

    You can add a user or a group. In our example, we add a group.

  10. Click Add.
    The Add User or Group window appears.
  11. For Type, select Group.
  12. In the Name text box, type a name for the group. The name of this group must match the Active Directory group your users belong to.

    If you add a user, the name of the user must match the name of the AuthPoint user or Active Directory user.

  13. From the Authentication Server drop-down list, select your authentication server.
  14. Click Save.
  15. This screenshot shows the configuration page for Mobile VPN with L2TP.

  16. Select the IPSec tab.
  17. Select the Enable IPSec check box.
  18. In the Credential Method section, select Use Pre-Shared Key.
  19. In the adjacent text box, type a pre-shared key. You must specify this same key when you configure the VPN client.
  20. This screenshot shows IPSec enabled for Mobile VPN with L2TP.

  21. Click Save.

Configure AuthPoint

Before AuthPoint can receive authentication requests from your Firebox, you must add a RADIUS client resource for the Firebox in AuthPoint. You must also assign an access policy for Firebox resource to the AuthPoint user group(s) that will authenticate through Mobile VPN with L2TP.

Add a RADIUS Client Resource in AuthPoint

From the AuthPoint management UI:

  1. From the navigation menu, select Resources.
  2. From the Choose a Resource Type drop-down list, select RADIUS Client. Click Add Resource.

  1. In the Name text box, type a descriptive name for the resource.
  2. In the RADIUS client trusted IP or FQDN text box, type the Trusted IP address of your Firebox.
  3. From the Value sent for RADIUS attribute 11 (Filter-Id) drop-down list, specify what is sent for the attribute 11 (Filter-ID) value in RADIUS responses. You can choose to send the user's AuthPoint group or the user's Active Directory groups.
  4. In the Shared Secret text box, type the shared secret key that you specified in the Configure Microsoft NPS Server and Configure RADIUS Authentication section. This is the password that the RADIUS server (AuthPoint Gateway) and the RADIUS client (Firebox) will use to communicate.
  5. To configure the RADIUS client resource to accept MS-CHAPv2 authentication requests, click the Enable MS-CHAPv2 toggle.
    Additional fields appear.

    If the L2TP VPN client is only used by local AuthPoint users, you do not have to enable MS–CHAPv2. Continue to Step 11.

  6. In the NPS RADIUS Server trusted IP or FQDN text box, type the IP address or fully qualified domain name (FQDN) of the NPS RADIUS server.
  7. In the Port text box, type 1812.

    If NPS and the Gateway are installed on the same server, the port that the Gateway uses to communicate with NPS must be different than the port that the Gateway uses to communicate with the RADIUS client.

  8. In the Timeout In Seconds text box, type 30.
  9. This screenshot shows the settings for the RADIUS client resource in AuthPoint.

  10. Click Save.

Add an Access Policy to AuthPoint

You must have at least one user group in AuthPoint, and you must assign an access policy for the Firebox resource to that group. If you already have a group, you do not have to add another group.

In the AuthPoint management UI:

  1. From the navigation menu, select Groups.
  2. To add a new group, click Add Group. If you already have a group that you want to use, click the Name of your group to edit it.

  1. In the Name text box, type a descriptive name for the group.
  2. (Optional) In the Description text box, type a description of the group.

  1. In the Access Policy section, click Add Policy.

  1. In the Add Policy dialog box, from the Resource drop-down list, select the resource you want to add an access policy for.
  2. (Optional) To require that users type their password before they authenticate for this resource, select the Require Password Authentication toggle.
  3. For the authentication options allowed, select Push. This is the authentication method that users in this group use when they authenticate.

    The access policy for a RADIUS client resource that uses MS-CHAPv2 can only use the push authentication method. You cannot use the OTP authentication method if MS-CHAPv2 is enabled.

  1. Click Add.
    The access policy for your resource is added to the list.

  1. Click Save.

Bind the RADIUS Resource to a Gateway

To use RADIUS authentication with AuthPoint, you must have the AuthPoint Gateway installed on your corporate network and you must assign your RADIUS resources to the Gateway in the AuthPoint management UI. The Gateway functions as a RADIUS server.

If you have not already configured and installed the AuthPoint Gateway, see About Gateways.

To assign your RADIUS resources to the Gateway:

  1. From the navigation menu, select Gateway.
  2. Select the Name of the Gateway.
  3. In the RADIUS section, in the Port text box, type the port number used to communicate with the Gateway. The default ports are 1812 and 1645.
  4. In the Select a RADIUS resource drop-down list, select your RADIUS client resource.
  5. Click Save.

Sync Users to AuthPoint from Active Directory

You must create AuthPoint user accounts for your users. To sync users from Active Directory, you must add an LDAP external identity and create one or more queries.

In AuthPoint, LDAP external identities represent external user databases. They connect to user databases to get user account information and validate passwords. The queries you add to an external identity specify which users to sync from your Active Directory or LDAP database. They pull user information and create AuthPoint user accounts for the users that are found.

For detailed instructions to sync users from Active Directory, see Sync Users from Active Directory or LDAP.

Test the Integration

To test AuthPoint MFA with your L2TP VPN client, you authenticate with a mobile token on your mobile device. For RADIUS resources with MS-CHAPv2 enabled, you authenticate with a push notification (you receive a push notification in the mobile app that you must approve to authenticate).

  1. From a Windows 10 computer, select Settings.
  2. Select Network & Internet.
  3. Select VPN.
  4. Click Add a VPN connection.
    The Add a VPN connection window opens.
  5. From the VPN provider drop-down list, select Windows (built-in).
  6. In the Connection name text box, type a name. In our example, we type VPN-L2TP.
  7. In the Server name or address text box, type the DNS name or external IP address of the Firebox. In our example, the address is 203.0.113.2.
  8. From the VPN type drop-down list, select L2TP/IPsec with pre-shared key.
  9. From the Type of sign-in info drop-down list, select User name and password.
  10. Click Save.
    The Add a VPN connection window closes.
  11. In the Related Settings section, click Change adapter options.
  12. Right-click the name of the VPN you created and select Properties.
  13. Select the Security tab.
  14. From the Data encryption drop-down list, select Require encryption (disconnect if server declines).
  15. In the Authentication section, select Allow these protocols.
  16. Select Microsoft CHAP Version 2 as the only allowed protocol.
  17. Click Advanced settings.
  18. Select Use pre-shared key for authentication.
  19. In the Key text box, type the shared secret key that you specified in the Configure the Firebox section.
  20. Click OK to close the Advanced Properties and VPN Properties windows.
  21. Select the VPN you created. Click Connect.
  22. Type your user name and password.
  23. Approve the authentication request that is sent to your mobile device.
    The VPN connects successfully.
  24. A screenshot that shows the VPN connected successfully.

See Also

Firebox Mobile VPN with IKEv2 Integration with AuthPoint

Firebox Mobile VPN with SSL Integration with AuthPoint

Firebox Mobile VPN with IPSec Integration with AuthPoint