SAML v2 Identity Provider

Overview

Adding a Login button for a third-party SAML v2 identity provider to FusionAuth is simple. This guide will walk you through the steps necessary to enable a SAML v2 identity provider. In this example FusionAuth is the SAML service provider and we are configuring a connection to the SAML Identity Provider.


We also provide specific examples for configuring SAML with some providers whose implementation requires unique configuration. If you’d like us to provide additional examples, please open a request on GitHub.


Once you have completed this configuration you will be able to enable the SAML v2 login button for one or more FusionAuth Applications. Below is an example login page with a SAML v2 Identity Provider enabled for PiedPiper.

SAML v2 Login

Create a SAML v2 Identity Provider

To create an Identity Provider navigate to Settings → Identity Providers and click Add provider and select SAML v2 from the dialog.

This will take you to the Add SAML v2 panel. Here you will need to fill out the required fields. If you do not know the IdP endpoint of your SAML v2 provider, you will need to contact the identity provider owner to get the URL.

To enable this identity provider for an application, find your application name in the Applications configuration section at the bottom of this panel. You will always see the FusionAuth application, this application represents the FusionAuth user interface. If you wish to be able to log into FusionAuth with this provider you may enable this application.

In the following screenshot you will see that we have enabled this login provider for the Pied Piper application and enabled Create registration. Enabling create registration means that a user does not need to be manually registered for the application prior to using this login provider.

For example, when a new user attempts to log into the Pied Piper application using this identity provider, if their user does not exist in FusionAuth it will be created dynamically. Additionally, if the Create registration toggle has been enabled, the user will also be registered for the Pied Piper application in FusionAuth and assigned any default roles assigned by the application.

If you do not wish to automatically provision a user for this Application when logging in with this identity provider, leave Create registration off and you will need to manually register a user for this application before they may complete login with this provider.

That’s it, now the Login with PiedPiper button will show up on the login page.

Add SAML v2

Form Fields

Id Optional

An optional UUID. When this value is omitted a unique Id will be generated automatically.

Name Required

A unique name to identity the identity provider. This name is for display purposes only and it can be modified later if desired.

IdP endpoint Required

The URL of the SAML identity providers login page.

Callback URL (ACS) Read-only

This is the callback URI you will need to provide to your identity provider.

Issuer Required

The name of your FusionAuth deployment that is configured in the SAML identity provider.

Use NameId for email Optional

If this is enabled, FusionAuth will assume that the NameID in the SAML response contains the email address of the user.

Email claim required Required

The name of the email claim returned in the SAML response.

When Use NameId for email is enabled this field will not be displayed and will not be required.

Verification key Required

The public key or certificate that you must import into FusionAuth’s KeyMaster. This is the public key provided to you by the identity provider.

Button text Required

The text to be displayed in the button on the login form. This value is defaulted to Login with SAML but it may be modified to your preference.

Button image Optional

The image to be displayed in the button on the login form. When this value is omitted a default SAML icon will be displayed on the login button.

Reconcile lambda Optional

A lambda may be utilized to map custom claims returned from the SAML response.

To configure a lambda, navigate to Settings → Lambdas.

Managed domains Optional

You may optionally scope this identity provider to one or more managed domains. For example, if you were to use a SAML v2 identity provider for your employees, you may add your company domain piedpiper.com to this field.

Adding one or more managed domains for this configuration will cause this provider not to be displayed as a button on your login page. Instead of a button the login form will first ask the user for their email address. If the user’s email address matches one of the configured domains the user will then be redirected to this login provider to complete authentication. If the user’s email address does not match one of the configured domains, the user will be prompted for a password and they will be authenticated using FusionAuth.

These configured domains will be used by the Lookup API.

CORS Configuration

In order to complete the login request, the SAML v2 Identity Provider will make an HTTP POST request to the callback URL in FusionAuth. In order for this request to be allowed through the CORS filter you will need to navigate to Settings → System → CORS and add the SAML IdP origin as an Allowed Origin the CORS configuration.

Once you complete your SAML v2 Identity Provider configuration, if your CORS configuration is not yet configured to allow the login request to complete you wil be shown the following warning prompting you to complete the CORS configuration. See CORS Filter reference for additional details on modifying the CORS configuration.

SAMLv2 CORS Warning

Troubleshooting

A common pattern is to set up SAML as the login method for the FusionAuth application. This lets you keep all your users in the SAML system, and have FusionAuth delegate auth decisions to it. However, if your Identity Provider isn’t configured correctly, you can end up in a dead end, unable to log in. This might happen if you:

  • Set up SAML as the authentication method for your FusionAuth admin application.

  • Set the Managed domains to your domain. For example, example.com.

  • Don’t have any users with a domain that is different than example.com.

  • Accidentally misconfigure SAML and break authentication.

  • Log out of the FusionAuth admin application.

You won’t be able to log in to the FusionAuth admin application to correct the misconfiguration. You’ve locked down the FusionAuth admin application so that only valid logins can access it, but because of the misconfiguration, there is no account with a valid SAML login.

Unable to login with a managed domain and misconfigured Identity Provider.

This is a problem, but not an insurmountable one. Your options depend on when you discover the issue. If you are beginning your SAML configuration, you can avoid this scenario. Follow these steps:

  • Don’t set any value of Managed domains before you have tested the SAML configuration.

  • Test authentication in a different or incognito browser window, ensuring that an admin user account is always accessible to modify configuration.

  • Add an admin user account with a domain not in the Managed domains setting. Ensure this user is registered with the FusionAuth admin application and has the admin role.

  • Set up an API key. Navigate to Settings → API Keys to do so and make sure it has privileges to create users and registrations. This will open up options in the future to reset settings without using the administrative user interface.

If you are currently locked out of your FusionAuth application, you have fewer options:

  • If you have a known username and password that are not delegated to SAML (perhaps the initial account created when you set up FusionAuth) proceed to the FusionAuth admin login page. Append &showPasswordField=true to the end of the login URL. This will force the UI to show the password field.

  • If you have an API key with appropriate privileges, you can modify the configuration without using the administrative user interface. Add an admin user with a different email domain and sign into the admin interface to correct your SAML configuration. Here’s how you might do so (3c219e58-ed0e-4b18-ad48-f4f92793ae32 is the FusionAuth application Id):

Adding a New Admin User With a Different Domain
curl -XPOST -H "Authorization: $API_KEY" -H "Content-Type: application/json" \
-d '{"user": {"email": "user@differentdomain.com","password":"password"}, "registration": {"applicationId" : "3c219e58-ed0e-4b18-ad48-f4f92793ae32","roles":["admin"]}}' \
https://local.fusionauth.io/api/user/registration

If you have neither an API key nor a known user, you can restore from a database backup, modify the database directly if you have access, or re-install FusionAuth.