Perform the following steps to configure Authentication policy
for end users who access services through Captive Portal. Before
starting, ensure that your Security
Policy allows users to access the services and URL categories
that require authentication.
Before you configure an Authentication
policy rule, make sure you understand that the set of IPv4 addresses
is treated as a subset of the set of IPv6 addresses, as described
in detail in Policy.
Kerberos single sign-on (SSO)—Create a
Kerberos keytab for the firewall. Optionally, you can configure
the firewall to use Kerberos SSO as the primary authentication service
and, if SSO failures occur, fall back to an external service or
local database authentication.
Select the Type of authentication
service and related settings:
External service—Select the Type of
external server and select the Server Profile you
created for it.
Local database authentication—Set the Type to Local
Database. In the Advanced settings, Add the Captive
Portal users and user groups you created.
Kerberos SSO—Specify the Kerberos Realm and Import the Kerberos Keytab.
Configure
an authentication enforcement object.
The object associates each authentication profile with
a Captive Portal method. The method determines whether the first
authentication challenge (factor) is transparent or requires a user
response.
Select ObjectsAuthentication and Add an object.
Enter a Name to identify the object.
Select an Authentication Method for the
authentication service Type you specified
in the authentication profile:
browser-challenge—Select
this method if you want the client browser to respond to the first
authentication factor instead of having the user enter login credentials.
For this method, you must have configured Kerberos SSO in the authentication
profile or NT
LAN Manager (NTLM) authentication in the Captive Portal settings.
If the browser challenge fails, the firewall falls back to the web-form method.
web-form—Select this method if you
want the firewall to display a Captive Portal web form for users
to enter login credentials.
Select the Authentication Profile you configured.
Enter the Message that the
Captive Portal web form will display to tell users how to authenticate
for the first authentication factor.
Click OK to save the object.
Configure
an Authentication policy rule.
Create a rule for each set of users, services, and URL
categories that require the same authentication services and settings.
Select PoliciesAuthentication and Add a
rule.
Enter a Name to identify the rule.
Select Source and Add specific
zones and IP addresses or select Any zones
or IP addresses.
Select Destination and Add specific
zones and IP addresses or select any zones
or IP addresses.
The IP addresses can be resources (such as servers) for
which you want to control access.
Select Service/URL Category and select
or Add the services and service groups for which
the rule controls access (default is service-http).
Select or Add the URL
Categories for which the rule controls access (default is any).
For example, you can create a custom URL category that specifies
your most sensitive internal sites.
Select Actions and select the Authentication
Enforcement object you created.
Specify the Timeout period
in minutes (default 60) during which the firewall prompts the user
to authenticate only once for repeated access to services and applications.
Timeout is a tradeoff between tighter
security (less time between authentication prompts) and the user
experience (more time between authentication prompts). More frequent
authentication is often the right choice for access to critical
systems and sensitive areas such as a data center. Less frequent
authentication is often the right choice at the network perimeter
and for businesses for which the user experience is key.
The firewall displays this page so that users can authenticate
for any additional MFA factors.
Verify that the firewall enforces Authentication policy.
Log in to your network as one of the source
users specified in an Authentication policy rule.
Request a service or URL category that matches one
specified in the rule.
The firewall displays the Captive Portal web form for the
first authentication factor. For example:
If
you configured the firewall to use one or more MFA services, authenticate
for the additional authentication factors.
End the session for the service or URL you just accessed.
Start a new session for the same service or application.
Be sure to perform this step within the Timeout period
you configured in the Authentication rule.
The firewall allows access without re-authenticating.
Wait until the Timeout period
expires and request the same service or application.