SSO and proxy considerations for MDX apps 编辑

Endpoint Management integration with Citrix Gateway enables you to provide users with single sign-on (SSO) to all back end HTTP/HTTPS resources. Depending on your SSO authentication requirements, you can configure user connections for an MDX app to use either of these options:

• Secure Browse (Tunneled - Web SSO), which is a type of clientless VPN
• Full VPN Tunnel (not available for Citrix Mobile productivity apps for iOS)

Important:

Citrix deprecated support for a full VPN tunnel and a Proxy Automatic Configuration (PAC) file with a full VPN tunnel deployment for iOS and Android devices. For more information, see Deprecation.

If Citrix Gateway isn’t the best way to provide SSO in your environment, you can set up an MDX app with policy-based local password caching. This article explores the various SSO and proxy options, with a focus on Secure Web. The concepts apply to other MDX apps.

The following flow chart summarizes the decision flow for SSO and user connections.

Citrix Gateway authentication methods

This section provides general information about the authentication methods supported by Citrix Gateway.

SAML authentication

When you configure Citrix Gateway for Security Assertion Markup Language (SAML), users can connect to web apps that support the SAML protocol for single sign-on. Citrix Gateway supports the identity provider (IdP) single sign-on for SAML web apps.

Required configuration:

• Configure SAML SSO in the Citrix Gateway Traffic profile.
• Configure the SAML IdP for the requested service.

NTLM authentication

If SSO to web apps is enabled in the session profile, Citrix Gateway performs NTLM authentication automatically.

Required configuration:

• Enable SSO in the Citrix Gateway Session or Traffic profile.

Kerberos impersonation

Endpoint Management supports Kerberos for Secure Web only. When you configure Citrix Gateway for Kerberos SSO, Citrix Gateway uses impersonation when a user password is available to Citrix Gateway. Impersonation means that Citrix Gateway uses user credentials to get the ticket required to gain access to services, such as Secure Web.

Required configuration:

• Configure the Citrix Gateway Worx Session policy to allow it to identify the Kerberos Realm from your connection.
• Configure a Kerberos Constrained Delegation (KCD) account on Citrix Gateway. Configure that account with no password and bind it to a traffic policy on your Endpoint Management gateway.
• For those and other configuration details, see the Citrix blog: WorxWeb and Kerberos Impersonation SSO.

Kerberos Constrained Delegation

Endpoint Management supports Kerberos for Secure Web only. When you configure Citrix Gateway for Kerberos SSO, Citrix Gateway uses constrained delegation when a user password is not available to Citrix Gateway.

With constrained delegation, Citrix Gateway uses a specified administrator account to get tickets on behalf of users and services.

Required configuration:

• Configure a KCD account in Active Directory with the required permissions and a KDC account on Citrix Gateway.
• Enable SSO in the Citrix Gateway Traffic profile.
• Configure the back-end website for Kerberos authentication.

Form Fill Authentication

When you configure Citrix Gateway for Form-based single sign-on, users can log on one time to access all protected apps in your network. This authentication method applies to apps that use Tunneled - Web SSO or Full VPN modes.

Required configuration:

• Configure Form-based SSO in the Citrix Gateway Traffic profile.

Digest HTTP authentication

If you enable SSO to web apps in the session profile, Citrix Gateway performs digest HTTP authentication automatically. This authentication method applies to apps that use Tunneled - Web SSO or Full VPN modes.

Required configuration:

• Enable SSO in the Citrix Gateway Session or Traffic profile.

Basic HTTP authentication

If you enable SSO to web apps in the session profile, Citrix Gateway performs basic HTTP authentication automatically. This authentication method applies to apps that use Tunneled - Web SSO or Full VPN modes.

Required configuration:

• Enable SSO in the Citrix Gateway Session or Traffic profile.

Secure Tunneled - Web SSO, Full VPN Tunnel, or Full VPN Tunnel with PAC

The following sections describe the user connection types for Secure Web.

Full VPN Tunnel

Connections that tunnel to the internal network can use a full VPN tunnel. Use the Secure Web Preferred VPN mode policy to configure full VPN tunnel. Citrix recommends a full VPN tunnel for connections that use client certificates or end-to-end SSL to a resource in the internal network. A full VPN tunnel handles any protocol over TCP.

You can use a full VPN tunnel with Windows and Mac devices. Full VPN isn’t available for Citrix Mobile productivity apps for iOS.

In Full VPN Tunnel mode, Citrix Gateway does not have visibility inside an HTTPS session.

Tunneled - Web SSO

Connections that tunnel to the internal network can use a variation of a clientless VPN, referred to as Tunneled - Web SSO. Tunneled - Web SSO is the default configuration specified for the Secure Web Preferred VPN mode policy. Citrix recommends Tunneled - Web SSO for connections that require single sign-on (SSO).

In Tunneled - Web SSO mode, Citrix Gateway breaks the HTTPS session into two parts:

• From the client to Citrix Gateway
• From Citrix Gateway to the back-end resource server.

In this manner, Citrix Gateway has full visibility into all transactions between the client and server, enabling it to provide SSO.

You can also configure proxy servers for Secure Web when used in Tunneled - Web SSO mode. For details, see the blog Endpoint Management WorxWeb Traffic Through Proxy Server in Secure Browse Mode.

Full VPN Tunnel with PAC

Note:

Citrix announced the deprecation of Full VPN tunnel with PAC. See Deprecation.

Endpoint Management supports proxy authentication provided by Citrix Gateway. A PAC file contains rules that define how web browsers select a proxy to access a given URL. PAC file rules can specify handling for both internal and external sites. Secure Web parses PAC file rules and sends the proxy server information to Citrix Gateway. Citrix Gateway is unaware of the PAC file or proxy server.

For authentication to HTTPS websites: The Secure Web MDX policy, Enable web password caching, enables Secure Web to authenticate and provide SSO to the proxy server through MDX.

Citrix Gateway Split Tunneling

When planning your SSO and proxy configuration, you must also decide whether to use Citrix Gateway split tunneling. Citrix recommends that you use Citrix Gateway split tunneling only if needed. This section provides a high-level look at how split tunneling works: Citrix Gateway determines the traffic path based on its routing table. When Citrix Gateway split tunneling is on, Secure Hub distinguishes internal (protected) network traffic from Internet traffic. Secure Hub makes that determination based on the DNS suffix and Intranet applications. Secure Hub then tunnels only the internal network traffic through the VPN tunnel. When Citrix Gateway split tunneling is off, all traffic goes through the VPN tunnel.

• If you prefer to monitor all the traffic due to security considerations, disable Citrix Gateway split tunneling. As a result, all traffic goes through the VPN tunnel.
• If you use Full VPN Tunnel with PAC, you must disable Citrix Gateway split tunneling. If split tunneling is on and you configure a PAC file, the PAC file rules override the Citrix Gateway split tunneling rules. A proxy server configured in a traffic policy does not override the Citrix Gateway split tunneling rules.

Citrix Gateway also has a micro VPN reverse split tunnel mode. This configuration supports an exclusion list of IP addresses that aren’t tunneled to the Citrix Gateway. Instead, those addresses are sent by using the device internet connection. For more information about reverse split tunneling, see the Citrix Gateway documentation.

Endpoint Management includes a Reverse split tunnel exclusion list. To prevent certain websites from tunneling through Citrix Gateway: Add a comma-separated list of fully qualified domain names (FQDN) or DNS suffixes that connect by using the LAN instead. This list applies only to Tunneled - Web SSO mode with Citrix Gateway configured for reverse split tunneling.