jit-migration-v2

Azure AD B2C: Just in time user migration v2

When you plan to migrate your identity provider to Azure AD B2C, you may also need to migrate the users account as well. This article explains how to migrate existing user accounts with their passwords and profiles, from any identity provider database to Azure AD B2C.

Just in time migration flow fits when the user's password is not accessible. For example:

• Passwords are in HASH format
• Passwords are stored in an identity provider, which you don't have access. Your system validates user credential by calling an identity provider web service

Just in time migration flow

Just in time migration deals with following scenarios:

Sign-in

1. SelfAsserted-LocalAccountSignin-Email technical profile calls the migration REST API endpoint, REST-UserMigration-LocalAccount-SignIn technical profile, sending SigninNames and password claims, as input parameters.
2. The REST API, checks if the user exists in the legacy identity provider. In this example Azure Blob Table.
3. If exists, REST API checks if the password provided by the user is valid (compare password or call the legacy identity provider).
   1. If valid the REST API returns the user profile from the migration table with needToMigrate claim set to local.
   2. If not valid, the REST API return an error 'Your password is incorrect'.
   3. If user is not existed in the legacy identity provider, the REST API returns empty claims (needToMigrate claim is null)
4. The SelfAsserted-LocalAccountSignin-Email technical profile checks the return needToMigrate claim.
   1. If the claim is null, Azure AD B2C invokes the next validation technical profile login-NonInteractive, which validates the user credential (this user already existed in the directory).
   2. Otherwise, Azure AD B2C invokes the next validation technical profile AAD-MigrateUserUsingLogonEmail, which migrates the account with the information return from the migration REST API.

Sign-up

For the sign-up the policy needs to check whether a user with such email address exists in Azure AD and also in the migration table. To do so, the LocalAccountSignUpWithLogonEmail technical profile:

1. Calls the migration REST API endpoint, REST-UserMigration-LocalAccount-SignUp technical profile, sending SigninNamesclaims.
2. The REST API checks if the user exists in the migration table.
3. If exists, return an error message 'A user with the specified ID already exists. Choose a different one.'
4. Otherwise, B2C continues to the next validation technical profile AAD-UserWriteUsingLogonEmail that checks if user already exists in AAD and creates the account.

Password reset

The password reset flow includes two pages. In the first page (LocalAccountDiscoveryUsingEmailAddress self-asserted technical profile) asks the user to provide and verify the email address. This technical profile:

1. Calls the AAD-UserReadUsingEmailAddress validation technical profile that looks up the user in AAD. While continuing on error (user not found), which means this user is a migrated one.
2. Then also makes a call to the REST-UserMigration-LocalAccount-PasswordReset1 validation technical profile, while sending the objectId. The REST API checks if user exists in the migration table, or if objectId is null. Raise an error is user is not existed in AAD or migration table.

On the second page, LocalAccountWritePasswordUsingObjectId self-asserted technical profile, user provides the new password and click continue.

1. For existing account (objectId is not null) Call AAD-UserWritePasswordUsingObjectId validation technical profile that updates the new password.
2. For migrate account (objectId is null)
   1. Call REST-UserMigration-LocalAccount-PasswordReset2 validation technical profile that returns the migrate user data.
   2. Call AAD-MigrateUserUsingLogonEmail validation technical profile that creates the account in the directory.

Unit tests

You should run at least following tests:

Test	Flow	Expected result
1	Sign-in with local account wrong password	Error message: Your password is incorrect
2	Sign-in with local account valid credentials	B2C issues an access token
3	Sign-in with invalid account	Error message: We can't seem to find your account
4	Sign-in with migrate account wrong credentials	Error message: Your password is incorrect (migration API)
5	Sign-in with migrate account valid credentials	User is migrated
6	Sign-in again with the same user and password	B2C issues an access token
7	Sign-Up with existing local account	Error message: A user with the specified ID already exists. Choose a different one.
8	Sign-Up with existing migration account	Error message: A user with the specified ID already exists. Choose a different one. (migration API)
9	Sign-Up with new account	B2C creates the account in the directory
10	Password reset for non-existing local and migrated account	Error message: An account could not be found for the provided user ID. (migration API)
11	Password reset for local account	Password is reset.
12	Try to sign-in again with the new password	B2C issues an access token
13	Password reset for migrated account	User is migrated (check the users list in Azure Portal)
14	Try to sign-in again with the new password	B2C issues an access token

Just in time migration .Net core solution

Migration database

This demo web API illustrates a case when username and password (in HASH format) are stored in Azure Tables. Azure table serves as your legacy identity provider. You can change to code to work directly with your legacy identity provider. Or export the data to Azure Table.

Populate the table with dummy data. Call following endpoint (replace URL to fit your deployment): http://your-app.azurewebsites.net/api/test/PopulateMigrationTable

Note: You can customize the Restful service to accommodate your own business logic. For example, validate user credential against SQL database, No-SQL or calling remote web services. The idea is the same: if the password provided by user is valid, update the AAD account and remove the entity.

Application Settings

To test the demo Restful API. Open the AADB2C.JITUserMigration.sln Visual Studio solution in Visual Studio. In the AADB2C.JITUserMigration project, open the appsettings.json. Replace the app settings with your own values:

"AppSettings": {
    "BlobStorageConnectionString": "<Your connection string to Azure Table that stores your identities to be migrated>"

  }

Run the solution

To run the visual studio solution, you need:

1. Deploy this web app to Azure App Services. For more information, see Create and publish the web app
2. Set the application settings. You can set the app settings directly from launchSettings.json file. Or use the better solution, from Azure portal. For more information, see: Configure web apps in Azure App Service
3. Open the policies files, change the tenant name, client_id and IdTokenAudience for Local Account sign-in, and upload the policies to Azure portal.

Important notes:

Secure the communication between Azure AD B2C to your Rest API. For more information, see: Secure your RESTful service by using client certificates OR Secure your RESTful services by using HTTP basic authentication

Solution artifacts

Azure AD custom policy

This sample policy is based on LocalAccounts starter pack.

• All changes are marked with Demo: comment inside the policy XML files.
• Make the necessary changes in the Action required comments

Visual studio solution

• UserMigrationController The custom policy calls this REST API
• TestController populate the Azure Table with migration dummy data.
• appsettings.json application settings
• Models folder - this folder contains the necessary object-mapping classes

Disclaimer

The migration application is developed and managed by the open-source community in GitHub. The application is not part of Azure AD B2C product and it's not supported under any Microsoft standard support program or service. This migration app is provided AS IS without warranty of any kind.