As business applications move from on-premises to cloud hosted solutions, users experience password fatigue due to disparate logons for different applications. Single sign-on (SSO) technologies seek to unify identities across systems and reduce the number of different credentials a user has to remember or input to gain access to resources.
While SSO is convenient for users, it presents new security challenges. If a user's primary password is compromised, attackers may be able to gain access to multiple resources. In addition, as sensitive information makes its way to cloud-hosted services it is even more important to secure access by implementing two-factor authentication.
Duo Access Gateway (DAG), our on-premises SSO product, layers Duo's strong authentication and flexible policy engine on top of Heroku logins using the Security Assertion Markup Language (SAML) 2.0 authentication standard. Duo Access Gateway acts as an identity provider (IdP), authenticating your users using existing on-premises or cloud-based directory credentials and prompting for two-factor authentication before permitting access to Heroku.
Duo Access Gateway is included in the Duo Beyond, Duo Access, and Duo MFA plans, which also include the ability to define policies that enforce unique controls for each individual SSO application. For example, you can require that Salesforce users complete two-factor authentication at every login, but only once every seven days when accessing Heroku. Duo checks the user, device, and network against an application's policy before allowing access to the application.
Add the attribute from the table below that corresponds to the Duo Mail attribute in the "Attributes" field when configuring your Active Directory or OpenLDAP authentication source in the DAG admin console. For example, if Active Directory is your authentication source, enter mail in the "Attributes" field.
|Duo Attribute||Active Directory||OpenLDAP|
If your organization uses another directory attribute than the ones listed here then enter that attribute name instead. If you've already configured the attributes list for another cloud service provider, append the additional attributes not already present to the list, separated by a comma.
After completing the initial DAG configuration steps, click Applications on the left side of the Duo Access Gateway admin console.
Scroll down the Applications page to the Metadata section. This is the information you need to provide to Heroku when configuring SSO. Click the Download XML metadata link to obtain the DAG metadata file (the downloaded file is named "dag.xml").
Log on to the Duo Admin Panel and navigate to Applications.
Click Protect an Application and locate the "Duo Access Gateway (self-hosted)" entry for Heroku in the applications list. Click Protect to the far-right to start configuring Heroku. See Protecting Applications for more information about protecting applications in Duo and additional application options.
The Organization name is defined in your Heroku Enterprise account under Settings. Enter your organization name in this field. Example of an organization name would be your-company.
Heroku uses the Mail attribute when authenticating. We've mapped Mail attribute to DAG supported authentication source attributes as follows:
|Duo Attribute||Active Directory||OpenLDAP||SAML IdP||Azure|
Click Save Configuration to generate a downloadable configuration file.
You can adjust additional settings for your new SAML application at this time — like changing the application's name from the default value, enabling self-service, or assigning a group policy — or come back and change the application's policies and settings after you finish SSO setup. If you do update any settings, click the Save Changes button when done.
Click the Download your configuration file link to obtain the Heroku application settings (as a JSON file).
Important: This file contains information that uniquely identifies this application to Duo. Secure this file as you would any other sensitive or password information. Don't share it with unauthorized individuals or email it to anyone under any circumstances!
Before you do this, verify that you updated the "Attributes" list for your Duo Access Gateway authentication source as specified here.
Return to the Applications page of the DAG admin console session.
Click the Choose File button in the "Add Application" section of the page and locate the Heroku SAML application JSON file you downloaded from the Duo Admin Panel earlier. Click the Upload button after selecting the JSON configuration file.
The Heroku SAML application is added.
Add the Duo Access Gateway as a new single sign-on provider for Heroku.
Log on to Heroku as an administrative user and click on Personal apps in the upper left hand corner. Select your company account from the dropdown. You will be taken to your company's Heroku page. Click the Settings link.
On the "Settings" page scroll down to Single Sign-on, click Upload Metdata, and select the dag.xml metadata file downloaded earlier. The page will automatically reload and display the message "Your IdP metadata file was sucessfully loaded." SSO is now enabled on your Heroku account.
Learn more about Heroku SSO at the Heroku Dev Center.
Navigate to the Heroku login page and click the Log in via SSO link. Enter your email address and click Continue. This redirects to the Duo Access Gateway login page. Enter your primary directory logon information, approve Duo two-factor authentication, and get redirected back to the Heroku site after authenticating.
The first time existing Heroku users log into Heroku with SSO, they may be asked to verify their account with their original Heroku username and password. They will then be asked to click Upgrade my Account which will change their account to work only with SSO.
Congratulations! Your Heroku users now authenticate using Duo Access Gateway.
If you plan to permit use of WebAuthn authentication methods (security keys, U2F tokens, or Touch ID), Duo recommends enabling hostname whitelisting for this application and any others that show the inline Duo Prompt before onboarding your end-users.
Microsoft's Active Directory Federation Services (AD FS) is a popular choice for SSO because it easily integrates with the AD identity store many organizations already have deployed. Duo's support for cloud applications and SSO drops in to an existing AD FS installation to provide secondary authentication after a user passes primary authentication (successful Active Directory logon).
If you don't already have AD federation running the first step is to install and configure Microsoft AD FS in your organization. Deployment Guides for AD FS versions 2.1, and 3.0/4.0 are available from Microsoft.
Once your AD FS services are up and running, the second step is to configure the SSO partnership between your AD FS service and the external cloud resource, in this case Heroku. Learn more about configuring Heroku SSO with AD FS at the Heroku Dev Center.
After you have successfully configured and tested AD FS SSO login to Heroku using your AD domain credentials, you can then install the Duo AD FS integration. AD FS protection is included with Duo's paid plans.
With the Duo integration for AD FS installed, users pass primary authentication to the AD FS service as usual. Once primary authentication succeeds, users are forwarded to the Duo service for secondary authentication. After approving logon using one of Duo's authentication methods, the user is fully logged in to Heroku.
Using a third-party SSO provider for cloud application access? Duo partners with leading cloud SSO providers like Okta and OneLogin to secure access with our strong and flexible authentication platform.