Set up sign-in with a Salesforce SAML provider by using SAML protocol - Azure AD B2C

Article
10/14/2024

Before you begin, use the Choose a policy type selector at the top of this page 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.

This feature is available only for custom policies. For setup steps, select Custom policy in the preceding selector.

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. If you've not done so, learn about custom policy starter pack in Get started with custom policies in Active Directory B2C.

This article shows you how to enable sign-in for users from a Salesforce organization using custom policies in Azure Active Directory B2C (Azure AD B2C). You enable sign-in by adding a SAML identity provider to a custom policy.

Prerequisites

Complete the steps in Get started with custom policies in Active Directory B2C. This tutorial guides you how to update custom policy files to use your Azure AD B2C tenant configuration.
If you haven't registered a web app, register one by using the steps in register a web application.

If you haven't already done so, sign up for a free Developer Edition account. This article uses the Salesforce Lightning Experience.
Set up a My Domain for your Salesforce organization.

Set up Salesforce as an identity provider

Sign in to Salesforce.
On the left menu, under Settings, expand Identity, and then select Identity Provider.
Select Enable Identity Provider.
Under Select the certificate, select the certificate you want Salesforce to use to communicate with Azure AD B2C. You can use the default certificate.
Click Save.

Create a connected app in Salesforce

On the Identity Provider page, select Service Providers are now created via Connected Apps. Click here.
Under Basic Information, enter the required values for your connected app.
Under Web App Settings, check the Enable SAML box.
In the Entity ID field, enter the following URL. Make sure that you replace the value for your-tenant with the name of your Azure AD B2C tenant.
```
https://your-tenant.b2clogin.cn/your-tenant.partner.onmschina.cn/B2C_1A_TrustFrameworkBase
```
In the ACS URL field, enter the following URL. Make sure that you replace the value for your-tenant with the name of your Azure AD B2C tenant.
```
https://your-tenant.b2clogin.cn/your-tenant.partner.onmschina.cn/B2C_1A_TrustFrameworkBase/samlp/sso/assertionconsumer
```
Scroll to the bottom of the list, and then click Save.

Get the metadata URL

On the overview page of your connected app, click Manage.
Copy the value for Metadata Discovery Endpoint, and then save it. You'll use it later in this article.

Set up Salesforce users to federate

On the Manage page of your connected app, click Manage Profiles.
Select the profiles (or groups of users) that you want to federate with Azure AD B2C. As a system administrator, select the System Administrator check box, so that you can federate by using your Salesforce account.

Create a self-signed certificate

If you don't already have a certificate, you can use a self-signed certificate. A self-signed certificate is a security certificate that is not signed by a certificate authority (CA) and doesn't provide the security guarantees of a certificate signed by a CA.

Windows
macOS

On Windows, use the New-SelfSignedCertificate cmdlet in PowerShell to generate a certificate.

Run the following PowerShell command to generate a self-signed certificate. Modify the -Subject argument as appropriate for your application and Azure AD B2C tenant name such as contosowebapp.contoso.partner.onmschina.cn. You can also adjust the -NotAfter date to specify a different expiration for the certificate.
```
New-SelfSignedCertificate `
    -KeyExportPolicy Exportable `
    -Subject "CN=yourappname.yourtenant.partner.onmschina.cn" `
    -KeyAlgorithm RSA `
    -KeyLength 2048 `
    -KeyUsage DigitalSignature `
    -NotAfter (Get-Date).AddMonths(12) `
    -CertStoreLocation "Cert:\CurrentUser\My"
```
On Windows computer, search for and select Manage user certificates
Under Certificates - Current User, select Personal > Certificates>yourappname.yourtenant.partner.onmschina.cn.
Select the certificate, and then select Action > All Tasks > Export.
Select Next > Yes, export the private key > Next.
Accept the defaults for Export File Format, and then select Next.
Enable Password option, enter a password for the certificate, and then select Next.
To specify a location to save your certificate, select Browse and navigate to a directory of your choice.
On the Save As window, enter a File name, and then select Save.
Select Next>Finish.

For Azure AD B2C to accept the .pfx file password, the password must be encrypted with the TripleDES-SHA1 option in the Windows Certificate Store Export utility, as opposed to AES256-SHA256.

Create a policy key

You need to store the certificate that you created in your Azure AD B2C tenant.

Sign in to the Azure portal.
If you have access to multiple tenants, select the Settings icon in the top menu to switch to your Azure AD B2C tenant from the Directories + subscriptions menu.
Choose All services in the top-left corner of the Azure portal, and then search for and select Azure AD B2C.
On the Overview page, select Identity Experience Framework.
Select Policy Keys and then select Add.
For Options, choose Upload.
Enter a Name for the policy. For example, SAMLSigningCert. The prefix B2C_1A_ is automatically added to the name of your key.
Browse to and select the B2CSigningCert.pfx certificate that you created.
Enter the Password for the certificate.
Click Create.

Add a claims provider

If you want users to sign in using a Salesforce 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 a Salesforce account as a claims provider by adding it to the ClaimsProviders element in the extension file of your policy. For more information, see define a SAML identity provider.

Open the TrustFrameworkExtensions.xml.
Find the ClaimsProviders element. If it does not exist, add it under the root element.

Add a new ClaimsProvider as follows:

<ClaimsProvider>
  <Domain>salesforce.com</Domain>
  <DisplayName>Salesforce</DisplayName>
  <TechnicalProfiles>
    <TechnicalProfile Id="Salesforce-SAML2">
      <DisplayName>Salesforce</DisplayName>
      <Description>Login with your Salesforce account</Description>
      <Protocol Name="SAML2"/>
      <Metadata>
        <Item Key="WantsEncryptedAssertions">false</Item>
        <Item Key="WantsSignedAssertions">false</Item>
        <Item Key="PartnerEntity">https://contoso-dev-ed.my.salesforce.com/.well-known/samlidp.xml</Item>
      </Metadata>
      <CryptographicKeys>
        <Key Id="SamlMessageSigning" StorageReferenceId="B2C_1A_SAMLSigningCert"/>
      </CryptographicKeys>
      <OutputClaims>
        <OutputClaim ClaimTypeReferenceId="issuerUserId" PartnerClaimType="userId"/>
        <OutputClaim ClaimTypeReferenceId="givenName" PartnerClaimType="given_name"/>
        <OutputClaim ClaimTypeReferenceId="surname" PartnerClaimType="family_name"/>
        <OutputClaim ClaimTypeReferenceId="email" PartnerClaimType="email"/>
        <OutputClaim ClaimTypeReferenceId="displayName" PartnerClaimType="username"/>
        <OutputClaim ClaimTypeReferenceId="authenticationSource" DefaultValue="socialIdpAuthentication"/>
        <OutputClaim ClaimTypeReferenceId="identityProvider" DefaultValue="salesforce.com" />
      </OutputClaims>
      <OutputClaimsTransformations>
        <OutputClaimsTransformation ReferenceId="CreateRandomUPNUserName"/>
        <OutputClaimsTransformation ReferenceId="CreateUserPrincipalName"/>
        <OutputClaimsTransformation ReferenceId="CreateAlternativeSecurityId"/>
        <OutputClaimsTransformation ReferenceId="CreateSubjectClaimFromAlternativeSecurityId"/>
      </OutputClaimsTransformations>
      <UseTechnicalProfileForSessionManagement ReferenceId="SM-Saml-idp"/>
    </TechnicalProfile>
  </TechnicalProfiles>
</ClaimsProvider>

Update the value of PartnerEntity with the Salesforce metadata URL you copied earlier.
Update the value of both instances of StorageReferenceId to the name of the key of your signing certificate. For example, B2C_1A_SAMLSigningCert.

Locate the <ClaimsProviders> section and add the following XML snippet. If your policy already contains the SM-Saml-idp technical profile, skip to the next step. For more information, see single sign-on session management.

<ClaimsProvider>
  <DisplayName>Session Management</DisplayName>
  <TechnicalProfiles>
    <TechnicalProfile Id="SM-Saml-idp">
      <DisplayName>Session Management Provider</DisplayName>
      <Protocol Name="Proprietary" Handler="Web.TPEngine.SSO.SamlSSOSessionProvider, Web.TPEngine, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />
      <Metadata>
        <Item Key="IncludeSessionIndex">false</Item>
        <Item Key="RegisterServiceProviders">false</Item>
      </Metadata>
    </TechnicalProfile>
  </TechnicalProfiles>
</ClaimsProvider>

Save the file.

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.

Open the TrustFrameworkBase.xml file from the starter pack.
Find and copy the entire contents of the UserJourney element that includes Id="SignUpOrSignIn".
Open the TrustFrameworkExtensions.xml and find the UserJourneys element. If the element doesn't exist, add one.
Paste the entire content of the UserJourney element that you copied as a child of the UserJourneys element.
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.

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.
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="SalesforceExchange" />
  </ClaimsProviderSelections>
  ...
</OrchestrationStep>

<OrchestrationStep Order="2" Type="ClaimsExchange">
  ...
  <ClaimsExchanges>
    <ClaimsExchange Id="SalesforceExchange" TechnicalProfileReferenceId="Salesforce-SAML2" />
  </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 CustomSignUpSignIn user journey, the ReferenceId is set to CustomSignUpSignIn:

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

Upload the custom policy

Sign in to the Azure portal.
Select the Directory + Subscription icon in the portal toolbar, and then select the directory that contains your Azure AD B2C tenant.
In the Azure portal, search for and select Azure AD B2C.
Under Policies, select Identity Experience Framework.
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

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

Set up sign-in with a Salesforce SAML provider by using SAML protocol in Azure Active Directory B2C