Set up sign-up and sign-in with a Microsoft account using Azure Active Directory B2C

Before you begin, use the Choose a policy type selector to choose the type of policy you’re setting up. Azure Active Directory B2C offers two methods to define how users interact with your applications: through predefined user flows or through fully configurable custom policies. The steps required in this article are different for each method.

Note

In Azure Active Directory B2C, custom policies are designed primarily to address complex scenarios. For most scenarios, we recommend that you use built-in user flows.

Prerequisites

Verify the application's publisher domain

As of November 2020, new application registrations show up as unverified in the user consent prompt unless the application's publisher domain is verified and the company’s identity has been verified with the Microsoft Partner Network and associated with the application. (Learn more about this change.) Note that for Azure AD B2C user flows, the publisher’s domain appears only when using a Microsoft account or other Azure AD tenant as the identity provider. To meet these new requirements, do the following:

  1. Verify your company identity using your Microsoft Partner Network (MPN) account. This process verifies information about your company and your company’s primary contact.
  2. Complete the publisher verification process to associate your MPN account with your app registration using one of the following options:

Create a Microsoft account application

To enable sign-in for users with a Microsoft account in Azure Active Directory B2C (Azure AD B2C), you need to create an application in Azure portal. For more information, see Register an application with the Microsoft identity platform. If you don't already have a Microsoft account, you can get one at https://www.live.com/.

  1. Sign in to the Azure portal.

  2. Make sure you're using the directory that contains your Azure AD tenant. Select the Directories + subscriptions icon in the portal toolbar.

  3. On the Portal settings | Directories + subscriptions page, find your Azure AD directory in the Directory name list, and then select Switch.

  4. Choose All services in the top-left corner of the Azure portal, and then search for and select App registrations.

  5. Select New registration.

  6. Enter a Name for your application. For example, MSAapp1.

  7. Under Supported account types, select Accounts in any organizational directory (Any Azure AD directory - Multitenant) and personal Microsoft accounts (e.g. Skype, Xbox).

    For more information on the different account type selections, see Quickstart: Register an application with the Microsoft identity platform.

  8. Under Redirect URI (optional), select Web and enter https://your-tenant-name.b2clogin.com/your-tenant-name.onmicrosoft.com/oauth2/authresp. If you use a custom domain, enter https://your-domain-name/your-tenant-name.onmicrosoft.com/oauth2/authresp. Replace your-tenant-name with the name of your tenant, and your-domain-name with your custom domain.

  9. Select Register

  10. Record the Application (client) ID shown on the application Overview page. You need the client ID when you configure the identity provider in the next section.

  11. Select Certificates & secrets

  12. Click New client secret

  13. Enter a Description for the secret, for example Application password 1, and then click Add.

  14. Record the application password shown in the Value column. You need the client secret when you configure the identity provider in the next section.

Configure Microsoft as an identity provider

  1. Sign in to the Azure portal as the global administrator of your Azure AD B2C tenant.
  2. Make sure you're using the directory that contains your Azure AD B2C tenant. Select the Directories + subscriptions icon in the portal toolbar.
  3. On the Portal settings | Directories + subscriptions page, find your Azure AD B2C directory in the Directory name list, and then select Switch.
  4. Choose All services in the top-left corner of the Azure portal, search for and select Azure AD B2C.
  5. Select Identity providers, then select Microsoft Account.
  6. Enter a Name. For example, MSA.
  7. For the Client ID, enter the Application (client) ID of the Azure AD application that you created earlier.
  8. For the Client secret, enter the client secret that you recorded.
  9. Select Save.

Add Microsoft identity provider to a user flow

At this point, the Microsoft identity provider has been set up, but it's not yet available in any of the sign-in pages. To add the Microsoft identity provider to a user flow:

  1. In your Azure AD B2C tenant, select User flows.
  2. Click the user flow that you want to add the Microsoft identity provider.
  3. Under the Social identity providers, select Microsoft Account.
  4. Select Save.
  5. To test your policy, select Run user flow.
  6. For Application, select the web application named testapp1 that you previously registered. The Reply URL should show https://jwt.ms.
  7. Select the Run user flow button.
  8. From the sign-up or sign-in page, select Microsoft to sign in with Microsoft account.

If the sign-in process is successful, your browser is redirected to https://jwt.ms, which displays the contents of the token returned by Azure AD B2C.

Configuring optional claims

If you want to get the family_name and given_name claims from Azure AD, you can configure optional claims for your application in the Azure portal UI or application manifest. For more information, see How to provide optional claims to your Azure AD app.

  1. Sign in to the Azure portal. Search for and select Azure Active Directory.
  2. From the Manage section, select App registrations.
  3. Select the application you want to configure optional claims for in the list.
  4. From the Manage section, select Token configuration (preview).
  5. Select Add optional claim.
  6. Select the token type you want to configure.
  7. Select the optional claims to add.
  8. Click Add.

Create a policy key

Now that you've created the application in your Azure AD tenant, you need to store that application's client secret in your Azure AD B2C tenant.

  1. Sign in to the Azure portal.
  2. Make sure you're using the directory that contains your Azure AD B2C tenant. Select the Directories + subscriptions icon in the portal toolbar.
  3. On the Portal settings | Directories + subscriptions page, find your Azure AD B2C directory in the Directory name list, and then select Switch.
  4. Choose All services in the top-left corner of the Azure portal, and then search for and select Azure AD B2C.
  5. On the Overview page, select Identity Experience Framework.
  6. Select Policy Keys and then select Add.
  7. For Options, choose Manual.
  8. Enter a Name for the policy key. For example, MSASecret. The prefix B2C_1A_ is added automatically to the name of your key.
  9. In Secret, enter the client secret that you recorded in the previous section.
  10. For Key usage, select Signature.
  11. Click Create.

Configure Microsoft as an identity provider

To enable users to sign in using a Microsoft account, you need to define the account as a claims provider that Azure AD B2C can communicate with through an endpoint. The endpoint provides a set of claims that are used by Azure AD B2C to verify that a specific user has authenticated.

You can define Azure AD as a claims provider by adding the ClaimsProvider element in the extension file of your policy.

  1. Open the TrustFrameworkExtensions.xml policy file.

  2. Find the ClaimsProviders element. If it does not exist, add it under the root element.

  3. Add a new ClaimsProvider as follows:

    <ClaimsProvider>
      <Domain>live.com</Domain>
      <DisplayName>Microsoft Account</DisplayName>
      <TechnicalProfiles>
        <TechnicalProfile Id="MSA-MicrosoftAccount-OpenIdConnect">
          <DisplayName>Microsoft Account</DisplayName>
          <Protocol Name="OpenIdConnect" />
          <Metadata>
            <Item Key="ProviderName">https://login.live.com</Item>
            <Item Key="METADATA">https://login.live.com/.well-known/openid-configuration</Item>
            <Item Key="response_types">code</Item>
            <Item Key="response_mode">form_post</Item>
            <Item Key="scope">openid profile email</Item>
            <Item Key="HttpBinding">POST</Item>
            <Item Key="UsePolicyInRedirectUri">false</Item>
            <Item Key="client_id">Your Microsoft application client ID</Item>
          </Metadata>
          <CryptographicKeys>
            <Key Id="client_secret" StorageReferenceId="B2C_1A_MSASecret" />
          </CryptographicKeys>
          <OutputClaims>
            <OutputClaim ClaimTypeReferenceId="issuerUserId" PartnerClaimType="oid" />
            <OutputClaim ClaimTypeReferenceId="givenName" PartnerClaimType="given_name" />
            <OutputClaim ClaimTypeReferenceId="surName" PartnerClaimType="family_name" />
            <OutputClaim ClaimTypeReferenceId="displayName" PartnerClaimType="name" />
            <OutputClaim ClaimTypeReferenceId="authenticationSource" DefaultValue="socialIdpAuthentication" />
            <OutputClaim ClaimTypeReferenceId="identityProvider" PartnerClaimType="iss" />
            <OutputClaim ClaimTypeReferenceId="email" />
          </OutputClaims>
          <OutputClaimsTransformations>
            <OutputClaimsTransformation ReferenceId="CreateRandomUPNUserName" />
            <OutputClaimsTransformation ReferenceId="CreateUserPrincipalName" />
            <OutputClaimsTransformation ReferenceId="CreateAlternativeSecurityId" />
            <OutputClaimsTransformation ReferenceId="CreateSubjectClaimFromAlternativeSecurityId" />
          </OutputClaimsTransformations>
          <UseTechnicalProfileForSessionManagement ReferenceId="SM-SocialLogin" />
        </TechnicalProfile>
      </TechnicalProfiles>
    </ClaimsProvider>
    
  4. Replace the value of client_id with the Azure AD application's Application (client) ID that you recorded earlier.

  5. Save the file.

You've now configured your policy so that Azure AD B2C knows how to communicate with your Microsoft account application in Azure AD.

Add a user journey

At this point, the identity provider has been set up, but it's not yet available in any of the sign-in pages. If you don't have your own custom user journey, create a duplicate of an existing template user journey, otherwise continue to the next step.

  1. Open the TrustFrameworkBase.xml file from the starter pack.
  2. Find and copy the entire contents of the UserJourney element that includes Id="SignUpOrSignIn".
  3. Open the TrustFrameworkExtensions.xml and find the UserJourneys element. If the element doesn't exist, add one.
  4. Paste the entire content of the UserJourney element that you copied as a child of the UserJourneys element.
  5. Rename the Id of the user journey. For example, Id="CustomSignUpSignIn".

Add the identity provider to a user journey

Now that you have a user journey, add the new identity provider to the user journey. You first add a sign-in button, then link the button to an action. The action is the technical profile you created earlier.

  1. Find the orchestration step element that includes Type="CombinedSignInAndSignUp", or Type="ClaimsProviderSelection" in the user journey. It's usually the first orchestration step. The ClaimsProviderSelections element contains a list of identity providers that a user can sign in with. The order of the elements controls the order of the sign-in buttons presented to the user. Add a ClaimsProviderSelection XML element. Set the value of TargetClaimsExchangeId to a friendly name.

  2. In the next orchestration step, add a ClaimsExchange element. Set the Id to the value of the target claims exchange Id. Update the value of TechnicalProfileReferenceId to the Id of the technical profile you created earlier.

The following XML demonstrates the first two orchestration steps of a user journey with the identity provider:

<OrchestrationStep Order="1" Type="CombinedSignInAndSignUp" ContentDefinitionReferenceId="api.signuporsignin">
  <ClaimsProviderSelections>
    ...
    <ClaimsProviderSelection TargetClaimsExchangeId="MicrosoftAccountExchange" />
  </ClaimsProviderSelections>
  ...
</OrchestrationStep>

<OrchestrationStep Order="2" Type="ClaimsExchange">
  ...
  <ClaimsExchanges>
    <ClaimsExchange Id="MicrosoftAccountExchange" TechnicalProfileReferenceId="MSA-MicrosoftAccount-OpenIdConnect" />
  </ClaimsExchanges>
</OrchestrationStep>

Configure the relying party policy

The relying party policy, for example SignUpSignIn.xml, specifies the user journey which Azure AD B2C will execute. Find the DefaultUserJourney element within relying party. Update the ReferenceId to match the user journey ID, in which you added the identity provider.

In the following example, for the CustomSignUpOrSignIn user journey, the ReferenceId is set to CustomSignUpOrSignIn:

<RelyingParty>
  <DefaultUserJourney ReferenceId="CustomSignUpSignIn" />
  ...
</RelyingParty>

Upload the custom policy

  1. Sign in to the Azure portal.
  2. Select the Directory + Subscription icon in the portal toolbar, and then select the directory that contains your Azure AD B2C tenant.
  3. In the Azure portal, search for and select Azure AD B2C.
  4. Under Policies, select Identity Experience Framework.
  5. Select Upload Custom Policy, and then upload the two policy files that you changed, in the following order: the extension policy, for example TrustFrameworkExtensions.xml, then the relying party policy, such as SignUpSignIn.xml.

Test your custom policy

  1. Select your relying party policy, for example B2C_1A_signup_signin.
  2. For Application, select a web application that you previously registered. The Reply URL should show https://jwt.ms.
  3. Select the Run now button.
  4. From the sign-up or sign-in page, select Microsoft to sign in with Microsoft account.

If the sign-in process is successful, your browser is redirected to https://jwt.ms, which displays the contents of the token returned by Azure AD B2C.