How to build Microsoft Entra ID OIDC enterprise SSO with iOS (Swift)

For our new friends:

Logto is an Auth0 alternative designed for modern apps and SaaS products. It offers both Cloud and Open-source services to help you quickly launch your identity and management (IAM) system. Enjoy authentication, authorization, and multi-tenant management all in one.

We recommend starting with a free development tenant on Logto Cloud. This allows you to explore all the features easily.

In this article, we will go through the steps to quickly build the Microsoft Entra ID OIDC enterprise SSO sign-in experience (user authentication) with iOS (Swift) and Logto.

Prerequisites

A running Logto instance. Check out the introduction page to get started.
Basic knowledge of iOS (Swift).
A usable Microsoft Entra ID OIDC enterprise SSO account.

Create an application in Logto

Logto is based on OpenID Connect (OIDC) authentication and OAuth 2.0 authorization. It supports federated identity management across multiple applications, commonly called Single Sign-On (SSO).

To create your Native app application, simply follow these steps:

Open the Logto Console. In the "Get started" section, click the "View all" link to open the application frameworks list. Alternatively, you can navigate to Logto Console > Applications, and click the "Create application" button.
In the opening modal, click the "Native app" section or filter all the available "Native app" frameworks using the quick filter checkboxes on the left. Click the "iOS (Swift)" framework card to start creating your application.
Enter the application name, e.g., "Bookstore," and click "Create application".

🎉 Ta-da! You just created your first application in Logto. You'll see a congrats page which includes a detailed integration guide. Follow the guide to see what the experience will be in your application.

Integrate iOS (Swift) SDK

Add Logto SDK as a dependency

Use the following URL to add Logto SDK as a dependency in Swift Package Manager.

https://github.com/logto-io/swift.git

Since Xcode 11, you can directly import a Swift package w/o any additional tool.

We do not support Carthage and CocoaPods at the time due to some technical issues.

Carthage

Carthage needs a xcodeproj file to build, but swift package generate-xcodeproj will report a failure since we are using binary targets for native social plugins. We will try to find a workaround later.

CocoaPods

CocoaPods does not support local dependency and monorepo, thus it's hard to create a .podspec for this repo.

Init LogtoClient

Initialize the client by creating a LogtoClient instance with a LogtoConfig object.

ContentView.swift
import Logto
import LogtoClient

let config = try? LogtoConfig(
  endpoint: "<your-logto-endpoint>", // E.g. http://localhost:3001
  appId: "<your-app-id>"
)
let client = LogtoClient(useConfig: config)

info:

By default, we store credentials like ID Token and Refresh Token in the Keychain. Thus the user doesn't need to sign in again when he returns.

To turn off this behavior, set usingPersistStorage to false:

let config = try? LogtoConfig(
  // ...
  usingPersistStorage: false
)

Before we dive into the details, here's a quick overview of the end-user experience. The sign-in process can be simplified as follows:

Your app invokes the sign-in method.
The user is redirected to the Logto sign-in page. For native apps, the system browser is opened.
The user signs in and is redirected back to your app (configured as the redirect URI).

This authentication process follows the OpenID Connect (OIDC) protocol, and Logto enforces strict security measures to protect user sign-in.
If you have multiple apps, you can use the same identity provider (Logto). Once the user signs in to one app, Logto will automatically complete the sign-in process when the user accesses another app.

To learn more about the rationale and benefits of redirect-based sign-in, see Logto sign-in experience explained.

Configure redirect URI

Let's switch to the Application details page of Logto Console. Add a Redirect URI io.logto://callback and click "Save changes".

info:

The Redirect URI in iOS SDK is only for internal use. There's NO NEED to add a Custom URL Scheme until a connector asks.

note:

Before calling .signInWithBrowser(redirectUri:), make sure you have correctly configured Redirect URI in Admin Console.

You can use client.signInWithBrowser(redirectUri:) to sign in the user and client.signOut() to sign out the user.

For example, in a SwiftUI app:

ContentView.swift
struct ContentView: View {
  @State var isAuthenticated: Bool

  init() {
    isAuthenticated = client.isAuthenticated
  }

  var body: some View {
    VStack {
      if isAuthenticated {
        Button("Sign Out") {
          Task { [self] in
            await client.signOut()
            isAuthenticated = false
          }
        }
      } else {
        Button("Sign In") {
          Task { [self] in
            do {
              try await client.signInWithBrowser(redirectUri: "${
                props.redirectUris[0] ?? 'io.logto://callback'
              }")
              isAuthenticated = true
            } catch let error as LogtoClientErrors.SignIn {
              // error occured during sign in
            } catch {
              // other errors
            }
          }
        }
      }
    }
  }
}

Checkpoint: Test your application

Now, you can test your application:

Run your application, you will see the sign-in button.
Click the sign-in button, the SDK will init the sign-in process and redirect you to the Logto sign-in page.
After you signed in, you will be redirected back to your application and see the sign-out button.
Click the sign-out button to clear token storage and sign out.

Add Microsoft Entra ID OIDC enterprise SSO connector

To simplify access management and gain enterprise-level safeguards for your big clients, connect with iOS (Swift) as a federated identity provider. The Logto enterprise SSO connector helps you establish this connection in minutes by allowing several parameter inputs.

To add an enterprise SSO connector, simply follow these steps:

Navigate to Logto console > Enterprise SSO.

SSO page

Click "Add enterprise connector" button and choose your SSO provider type. Choose from prebuilt connectors for Microsoft Entra ID (Azure AD), Google Workspace, and Okta, or create a custom SSO connection using the standard OpenID Connect (OIDC) or SAML protocol.
Provide a unique name (e.g., SSO sign-in for Acme Company).

Select your SSO provider

Configure the connection with your IdP in the "Connection" tab. Check the guides above for each connector types.

SSO connection

Customize the SSO experience and enterprise’s email domain in the "Experience" tab. Users sign in with the SSO-enabled email domain will be redirected to SSO authentication.

SSO experience

Save changes.

Set up Azure AD SSO application

Step 1: Create an Microsoft EntraID OIDC application

Go to the Microsoft Entra admin center and sign in as an administrator.
Browse to Identity > Applications > App registrations.

Select New registration.
Enter the application name and select the appropriate account type for your application.
Select Web as the application platform.
Copy and paste the redirect URI from Logto's SSO settings page. The redirect URI is the URL where the user is redirected after they have authenticated with Microsoft Entra ID.

Click Register to create the application.

Step 2: Configure Microsoft Entra ID OIDC SSO at Logto

After successfully creating an Microsoft Entra OIDC application, you will need to provide the IdP configurations back to Logto. Navigate to the Connection tab at Logto Console, and fill in the following configurations:

Client ID: A unique identifier assigned to your OIDC application by the Microsoft Entra. This identifier is used by Logto to identify and authenticate the application during the OIDC flow. You can find it in the application overview page as Application (client) ID.

Client Secret: Create a new client secret and copy the value to Logto. This secret is used to authenticate the OIDC application and secure the communication between Logto and the IdP.

Issuer: The issuer URL, a unique identifier for the IdP, specifying the location where the OIDC identity provider can be found. It is a crucial part of the OIDC configuration as it helps Logto discover the necessary endpoints.

Instead of manually provide all these OIDC endpoints, Logto fetch all the required configurations and IdP endpoints automatically. This is done by utilizing the issuer url you provided and making a call to the IdP's discover endpoint.

To get the issuer URL, you can find it in the Endpoints section of the application overview page.

Locate the OpenID Connect metadata document endpoint and copy the URL WITHOUT the trailing path .well-known/openid-configuration. This is because Logto will automatically append the .well-known/openid-configuration to the issuer URL when fetching the OIDC configurations.

Scope: A space-separated list of strings defining the desired permissions or access levels requested by Logto during the OIDC authentication process. The scope parameter allows you to specify what information and access Logto is requesting from the IdP.

The scope parameter is optional. Regardless of the custom scope settings, Logto will always send the openid, profile and email scopes to the IdP.

Click Save to finish the configuration process

Step 3: Set email domains and enable the SSO connector

Provide the email domains of your organization on the connector experience tab. This will enabled the SSO connector as an authentication method for those users.

Users with email addresses in the specified domains will be exclusively limited to use your SSO connector as their only authentication method.

Save your configuration

Double check you have filled out necessary values in the Logto connector configuration area. Click "Save and Done" (or "Save changes") and the Microsoft Entra ID OIDC enterprise SSO connector should be available now.

You don’t need to configure enterprise connectors individually, Logto simplifies SSO integration into your applications with just one click.

Navigate to: Console > Sign-in experience > Sign-up and sign-in.
Enable the "Enterprise SSO" toggle.
Save changes.

Once enabled, a "Single Sign-On" button will appear on your sign-in page. Enterprise users with SSO-enabled email domains can access your services using their enterprise identity providers (IdPs).

Auto detect SSO sign-in via email domain

To learn more about the SSO user experience, including SP-initiated SSO and IdP-initiated SSO, refer to User flows: Enterprise SSO.

Testing and Validation

Return to your iOS (Swift) app. You should now be able to sign in with Microsoft Entra ID OIDC enterprise SSO. Enjoy!

Create an application in Logto​

Integrate iOS (Swift) SDK​

Add Logto SDK as a dependency​

Carthage​

CocoaPods​

Init LogtoClient​

Sign in​

Regarding redirect-based sign-in​

Configure redirect URI​

Sign-in and sign-out​

Checkpoint: Test your application​

Add Microsoft Entra ID OIDC enterprise SSO connector​

Set up Azure AD SSO application​

Step 1: Create an Microsoft EntraID OIDC application​

Step 2: Configure Microsoft Entra ID OIDC SSO at Logto​

Step 3: Set email domains and enable the SSO connector​

Save your configuration​

Enable Microsoft Entra ID OIDC enterprise SSO connector in Sign-in Experience​

Testing and Validation​

Further readings​