- Change Log
- RADIUS Overview
- Two-factor Policies Summary
- Create Two-factor Policies – for RADIUS and LDAP
- Bind Two-factor Policies to Gateway
- 2019 Jun 17 – Create RADIUS Server – change password encoding to mschapv2
- 2018 Dec 5 – updated screenshots for ADC 12.1
- 2018 May 27 – RADIUS Server – added link to CTX222260 Radius Group Extraction from Windows Server 2008/2012 with NetScaler/CloudBridge
One method of two-factor authentication to Citrix Gateway is the RADIUS protocol with a two-factor authentication product (tokens) that has RADIUS enabled.
RADIUS Clients and Source IP – On your RADIUS servers, you’ll need to add the ADC appliances as RADIUS Clients. When ADC uses a local (same appliance) load balanced Virtual Server for RADIUS authentication, the traffic is sourced from the ADC SNIP (Subnet IP). When ADC uses a direct connection to a RADIUS Server without going through a load balancing Virtual Server, or uses a remote (different appliance) Load Balancing Virtual Server, the traffic is sourced from the ADC NSIP (ADC Management IP). Use the correct IP(s) when adding the ADC appliances as RADIUS Clients. And adjust firewall rules accordingly.
- For High Availability pairs, if you locally load balance RADIUS, then you only need to add the SNIP as a RADIUS Client, since the SNIP floats between the two appliances. However, if you are not locally load balancing RADIUS, then you’ll need to add the NSIP of both appliances as RADIUS Clients. Use the same RADIUS Secret for both appliances.
- For two-factor authentication using Azure Multi-factor Authentication, see Jason Samuel How to deploy Microsoft Azure MFA & AD Connect with Citrix NetScaler Gateway
- Citrix CTX125364 How to Configure Dual Authentication on NetScaler Gateway Enterprise Edition for Use with iPhone and iPad.
Some two-factor products (e.g. SMS Passcode) require you to hide the 2nd password field. Receiver 4.4 and newer supports hiding the 2nd field if you configure a Meta tag in index.html.
- CTX205907 Dual-Password Field Shows in First Authentication When Connecting to NetScaler Gateway from Windows Receiver for instructions.
- CTX203775 Citrix Receiver and 2-Step Verification Incompatibility
Two-factor Policies Summary
ADC has two methods of multi-factor:
- Citrix Gateway Virtual Server has bind points for Primary and Secondary authentication. This functionality is available in all ADC Editions and is detailed in this post.
- nFactor Authentication supports unlimited factors, but requires ADC Advanced Edition (formerly known as Enterprise Edition) or ADC Platinum Edition.
See the ADC 12 page for additional authentication mechanisms supported by NetScaler 12 and ADC 12.1. Some require nFactor.
When configuring the Citrix Gateway Virtual Server, you can specify both a Primary authentication policy, and a Secondary authentication policy. Users are required to successfully authenticate against both policies before being authorized for Citrix Gateway.
For browser-based StoreFront, you need two authentication policies:
- Primary = LDAPS authentication policy pointing to Active Directory Domain Controllers.
- Secondary = RADIUS authentication policy pointing to RSA servers with RADIUS enabled.
For Receiver Self-service (native Receiver on mobile, Windows, and Mac), the authentication policies are swapped:
- Primary = RADIUS authentication policy pointing to RSA servers with RADIUS enabled.
- Secondary = LDAPS authentication policy pointing to Active Directory Domain Controllers.
If you need to support two-factor authentication from both web browsers and Receiver Self-Service, then you’ll need at least four authentication policies as shown below.
- Priority 90 = RADIUS policy. Expression = REQ.HTTP..HEADER User-Agent CONTAINS CitrixReceiver
- Priority 100 = LDAP policy. Expression = REQ.HTTP..HEADER User-Agent NOTCONTAINS CitrixReceiver
- Priority 90 = LDAP policy. Expression = REQ.HTTP..HEADER User-Agent CONTAINS CitrixReceiver
- Priority 100 = RADIUS policy. Expression = REQ.HTTP..HEADER User-Agent NOTCONTAINS CitrixReceiver
Create Two-factor Policies
Create an LDAP Server/Action
See the LDAP post for instructions. Only the server/action is needed. The Policies will be created later.
Create a RADIUS Server/Action
- On the left, expand Authentication, and click Dashboard.
- On the right, click Add.
- Change Choose Server Type to RADIUS.
- Give the server a name.
- Specify the IP address of the RADIUS load balancing Virtual Server.
- Enter the secret key specified when you added the ADCs as RADIUS clients on the RADIUS server. Click Test RADIUS Reachability.
- Scroll down, and click More.
- Find the Password Encoding drop-down. Change it to mschapv2 if your RADIUS server supports it, c. Microsoft NPS requires mschapv2 to support changing expired Active Directory passwords. 💡
- If you want ADC to receive AAA Group information from RADIUS, see CTX222260 Radius Group Extraction from Windows Server 2008/2012 with NetScaler/CloudBridge.
- RADIUS attribute = 26 (Vendor-Specific)
- Vendor Code = 3845 (Citrix)
- Vendor-assigned attribute number = any number (e.g. 1). Configure RADIUS policy on ADC with same attribute number.
- Attribute value = Group Name
- Click Create.
add authentication radiusAction RSA -serverIP 10.2.2.210 -serverPort 1812 -authTimeout 60 -radKey Passw0rd -passEncoding mschapv2
Create Authentication Policies for LDAP and RADIUS
- Go to Citrix Gateway > Policies > Authentication > RADIUS.
- On the right, in the Policies tab, click Add.
- In the Create Authentication RADIUS Policy page:
- Name the policy RSA-ReceiverSelfService or similar.
- Select the RADIUS server created earlier.
- Enter an expression. You will need two policies with different expressions. The expression for Receiver Self-Service is REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver.
Note: Citrix Gateway 12.1 does not natively support binding of Advanced Authentication Policies so you’ll have to create them as Basic Policies (classic expressions). You can only bind Advanced Authentication Policies using nFactor.
- Click Create.
- If you see a warning about deprecation, click OK, and ignore it.
- Create another RADIUS policy to match the ones shown below. Both RADIUS policies are configured with the same RADIUS server. The only difference between them is the expression (CONTAINS vs NOTCONTAINS):
Name Expression Server RSA-ReceiverSelfService REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver RSA RSA-ReceiverForWeb REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver RSA
- Go to the Citrix Gateway\Policies\Authentication\LDAP node.
- On the Policies tab, create two policies with the expressions shown below. Both LDAP policies are configured with the same LDAP server. The only difference between them is the expression (CONTAINS vs NOTCONTAINS).
Name Expression Server LDAP-Corp-ReceiverSelfService REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver LDAP-Corp LDAP-Corp-ReceiverForWeb REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver LDAP-Corp
add authentication radiusPolicy RSA-ReceiverForWeb "REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver" RSA add authentication radiusPolicy RSA-ReceiverSelfService "REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver" RSA add authentication ldapPolicy Corp-Gateway-ReceiverForWeb "REQ.HTTP.HEADER User-Agent NOTCONTAINS CitrixReceiver" Corp-Gateway add authentication ldapPolicy Corp-Gateway-ReceiverSelfService "REQ.HTTP.HEADER User-Agent CONTAINS CitrixReceiver" Corp-Gateway
Bind Two-factor Policies to Gateway
- When you create or edit a Citrix Gateway Virtual Server, bind the Basic Authentication Policies as shown in the following table. Priority doesn’t matter because they are mutually exclusive.
Policy Name Type Bind Point LDAP-Corp-ReceiverForWeb LDAP Primary RSA-ReceiverSelfService RADIUS Primary LDAP-Corp-ReceiverSelfService LDAP Secondary RSA-ReceiverForWeb RADIUS Secondary
bind vpn vserver gateway.corp.com -policy Corp-Gateway-ReceiverForWeb -priority 100 bind vpn vserver gateway.corp.com -policy RSA-ReceiverSelfService -priority 110 bind vpn vserver gateway.corp.com -policy RSA-ReceiverForWeb -priority 100 -secondary bind vpn vserver gateway.corp.com -policy Corp-Gateway-ReceiverSelfService -priority 110 -secondary
- The Session Policy/Profile for Receiver Self-Service needs to be adjusted to indicate which authentication field contains the Active Directory password. On the Client Experience tab is Credential Index. This needs to be changed to SECONDARY. Leave the session policy for Web Browsers set to Primary.
set vpn sessionAction "Receiver Self-Service" -ssoCredential SECONDARY
- On the StoreFront server, when creating the NetScaler Gateway object, on the Authentication Settings page, change the Logon type to Domain and security token. This instructs Receiver / Workspace app to properly handle two-factor authentication. If you change this setting after Receiver / Workspace app has already performed discovery, then users might have to remove the Account from Receiver / Workspace app and re-add it.