Configure workforce identity federation

Preview — workforce identity federation

This feature is covered by the Pre-GA Offerings Terms of the Google Cloud Terms of Service. Pre-GA features might have limited support, and changes to pre-GA features might not be compatible with other pre-GA versions. For more information, see the launch stage descriptions.

This guide describes how to configure workforce identity federation with an identity provider (IdP) that supports OIDC or SAML 2.0.

For IdP-specific instructions, see the following:

• Configure Azure AD-based workforce identity federation
• Configure Okta-based workforce identity federation

Before you begin

1. You must have a Google Cloud organization set up.

2. Identify a billing/quota project.

   Note: Ask your Google Cloud account team to request access to workforce identity federation for this project. The account team notifies you when the project is granted access.

   To set the Google Cloud project that is billed and charged quota for operations performed in the gcloud CLI, execute the following command:

   gcloud config set billing/quota_project PROJECT_ID
   

   Replace PROJECT_ID with the project ID.

3. Enable the Identity and Access Management (IAM) and Resource Manager APIs.

   Enable the APIs

4. Install and initialize the Google Cloud CLI.

   Note: If you installed the gcloud CLI previously, make sure you have the latest version by running gcloud components update.

Required roles

To get the permissions that you need to configure workforce identity federation, ask your administrator to grant you the Workforce Identity Pool Admin (roles/iam.workforcePoolAdmin) IAM role on the organization. For more information about granting roles, see Manage access.

Alternatively, the Owner basic role (roles/owner) also includes permissions to configure workforce identity federation. You should not grant basic roles in a production environment, but you can grant them in a development or test environment.

Configure workforce identity federation

To configure workforce identity federation you create a workforce identity federation pool and a workforce identity federation pool provider.

Create a workforce identity pool

To create the pool, execute the following command:

gcloud iam workforce-pools create WORKFORCE_POOL_ID \
    --organization=ORGANIZATION_ID \
    --description="DESCRIPTION" \
    --location=global

Replace the following:

• WORKFORCE_POOL_ID: the workforce identity pool ID
• ORGANIZATION_ID: the numeric organization ID
• DESCRIPTION: a workforce identity pool description

Create a workforce identity pool provider

You can configure workforce identity pool providers in the following ways:

OIDC

To configure the OIDC provider, perform the following steps:

1. In your OIDC IdP, register a new application for Google Cloud workforce identity federation. Note the client ID and issuer URI provided by the IdP. You use them in this document.

2. If you plan to set up user access to the console, add the following redirect URL to your OIDC IdP:

   https://auth.cloud.google/signin-callback/locations/global/workforcePools/WORKFORCE_POOL_ID/providers/WORKFORCE_PROVIDER_ID
   

   To learn how to configure console (federated) sign-in, see Set up user access to the console (federated).

3. In Google Cloud, create an OIDC workforce identity pool provider by executing the following command:

gcloud iam workforce-pools providers create-oidc PROVIDER_ID \
  --workforce-pool=WORKFORCE_POOL_ID \
  --display-name="DISPLAY_NAME" \
  --description="DESCRIPTION" \
  --issuer-uri="ISSUER_URI" \
  --client-id="CLIENT_ID" \
  --attribute-mapping="ATTRIBUTE_MAPPING" \
  --attribute-condition="ATTRIBUTE_CONDITION" \
  --location=global

Replace the following:

• PROVIDER_ID: a unique provider ID
• WORKFORCE_POOL_ID: the workforce identity pool ID to connect your IdP to
• DISPLAY_NAME an optional user-friendly display name for the provider; for example, idp-eu-employees
• DESCRIPTION: an optional workforce provider description; for example, IdP for Partner Example Organization employees
• ISSUER_URI: the OIDC issue URI that Issuer, in a valid URI format, that starts with https; for example, https://example.com/oidc
• CLIENT_ID: the OIDC client ID that is registered with your OIDC IdP; the ID must match the aud claim of the JWT that is issued by your IdP
• ATTRIBUTE_MAPPING: an attribute mapping; for example, google.subject=assertion.sub, google.groups=[assertion.group1,assertion.group2], attribute.costcenter=assertion.costcenter
• ATTRIBUTE_CONDITION: an attribute condition; for example, assertion.role == 'gcp-users'

For OIDC federation, you can use assertion.NAME: a string equal to the value of the like-named claim in the ID token payload.

SAML

To configure the SAML provider, perform the following steps:

1. In your SAML IdP, register a new application for Google Cloud workforce identity federation.

2. Set the audience for SAML assertions. It is usually the SP Entity ID field in your IdP configuration. You must set it to the following URL:

   https://iam.googleapis.com/locations/global/workforcePools/WORKFORCE_POOL_ID/providers/PROVIDER_ID
   

3. If you plan to set up user access to the console, add the following redirect URL to your SAML IdP:

   https://auth.cloud.google/signin-callback/locations/global/workforcePools/WORKFORCE_POOL_ID/providers/WORKFORCE_PROVIDER_ID
   

   See Set up user access to the console for more details on configuring Console Sign-in.

4. In Google Cloud, create a SAML workforce identity pool provider using your IdP's SAML metadata doc. You can download the SAML metadata XML document from your IdP. The document must include at least the following:

   • A SAML entity ID for your IdP
   • The single-sign-on URL for your IdP
   • At least one signing public key.

   See Key requirements later in this guide for details on signing keys.

   gcloud iam workforce-pools providers create-saml PROVIDER_ID \
       --workforce-pool=WORKFORCE_POOL_ID \
       --display-name="DISPLAY_NAME" \
       --description="DESCRIPTION" \
       --idp-metadata-path=METADATA_FILE_PATH \
       --attribute-mapping="ATTRIBUTE_MAPPING" \
       --attribute-condition="ATTRIBUTE_CONDITION" \
       --location=global
   

   Replace the following:

   • PROVIDER_ID: the provider ID.
   • WORKFORCE_POOL_ID: the pool ID.
   • DISPLAY_NAME the display name for the provider; for example, idp-eu-employees
   • DESCRIPTION: the description for the workforce identity pool provider; for example, IdP for Partner Example Organization EU employees.
   • METADATA_FILE_PATH: the file path of the SAML metadata
   • ATTRIBUTE_MAPPING: the attribute mapping; for example, google.subject=assertion.subject, google.groups=assertion.attributes.groupList, attribute.costcenter=assertion.attributes.costcenter[0]
   • ATTRIBUTE_CONDITION: an attribute condition; for example: assertion.attributes.role[0] == 'gcp-users'

For SAML federation, you can use the following keywords in attribute mappings and conditions:

• assertion.subject: a string equal to the NameID attribute in the SAML assertion.
• assertion.attributes.NAME: a string list equal to the values of the like-named attributes in the SAML assertion.

Key requirements

The following key specifications apply to SAML:

• An RSA public key that is wrapped in an X.509 v3 certificate.

• Certificate validity requirements:

  • notBefore: a timestamp of no more than 7 days in the future.
  • notAfter: a timestamp no more than 14 years in the future.

• Recommended algorithms:

  • RSAwithSHA256 (supported key sizes (bits): 2048, 3072, 4096)
  • ECDSAwithSHA256

A workforce identity pool provider can be configured with at most three signing keys at a given time. When multiple keys exist, Google Cloud iterates through them and attempts to use each non-expired key to fulfill a token exchange request.

As a security best practice, we strongly recommend that you don't reuse the same key pair with other services.

Key management

Important: To ensure that your workforce users' access isn't disrupted when your keys expire, we recommend that you regularly update your keys. The public signing keys used to validate SAML assertion signatures have an expiration date. After the expiration date, the keys can't be used for token exchanges.

To update your IdP's signing keys, do the following:

1. Create a new asymmetric key pair and configure the SAML identity provider with the key pair. You initially mark it as inactive before activating it in a later step.

2. Download a SAML metadata XML document from your IdP.

   Note: The document must contain both the existing signing key and the newly created signing key.

3. Update the workforce identity pool provider resource using the SAML metadata document. When multiple keys exist, Google Cloud iterates through each non-expired key and attempts to it to fulfill a token exchange request.

   To update the workforce identity pool provider with the SAML metadata, execute the following command.

   gcloud iam workforce-pools providers update-saml PROVIDER_ID \
       --workforce-pool=WORKFORCE_POOL_ID \
       --idp-metadata-path=SAML_METADATA_FILE_PATH \
       --location=global
   

   Replace the following:

   • PROVIDER_ID: the provider ID
   • WORKFORCE_POOL_ID: the workforce identity pool ID
   • SAML_METADATA_FILE_PATH: the path to the SAML metadata file

4. Wait for the operation returned from the previous step to complete (the operation is marked as done), and then in your SAML IdP, activate the new signing key. The old signing key is marked as inactive. Assertions issued by your IdP are signed using the new key.

The following steps are optional, but we recommend you perform them as a best practice:

1. Delete the old, now inactive, signing key from your IdP.
2. Download the SAML metadata XML document from your IdP.

3. Update the workforce identity pool provider resource using the SAML metadata document. Google Cloud refuses assertions that are signed with the expired signing key. To update the document, execute the following command:

   gcloud iam workforce-pools providers update-saml PROVIDER_ID \
       --workforce-pool=WORKFORCE_POOL_ID \
       --idp-metadata-path=SAML_METADATA_FILE_PATH \
       --location=global
   

   Replace the following:

   • PROVIDER_ID: the provider ID
   • WORKFORCE_POOL_ID: the workforce identity pool ID
   • SAML_METADATA_FILE_PATH: the SAML metadata file path

Key deletion constraint

Google Cloud refuses assertions signed with a deleted key.

Caution: Accidentally deleting a key that is still in use can lead to outages. You can only update a workforce identity pool provider resource if the SAML metadata contains at least one non-expired signing key. This restriction is skipped if all existing signing keys are expired.

Represent workforce pool users in IAM policies

The following table shows the principal identifiers that you use to grant roles to a single user, a group of users, users carrying a particular claim, or all users from a workforce pool.

Note: You can't grant the Owner role (roles/owner) to a workforce user on projects.

Identities	Identifier format
Single identity in a workforce identity pool	principal://iam.googleapis.com/locations/global/workforcePools/POOL_ID/subject/SUBJECT_ATTRIBUTE_VALUE
All workforce identities in a group	principalSet://iam.googleapis.com/locations/global/workforcePools/POOL_ID/group/GROUP_ID
All workforce identities with a specific attribute value	principalSet://iam.googleapis.com/locations/global/workforcePools/POOL_ID/attribute.ATTRIBUTE_NAME/ATTRIBUTE_VALUE
All identities in a workforce identity pool	principalSet://iam.googleapis.com/locations/global/workforcePools/POOL_ID/*

Grant IAM roles to principals

You can grant roles to principals, such as single identities, groups of identities, or an entire pool.

To grant a role on a project to a principal, execute the following command:

gcloud projects add-iam-policy-binding PROJECT_ID \
    --role="ROLE" \
    --member="PRINCIPAL"

Replace the following:

• PROJECT_ID: the project ID
• ROLE: the role to set
• PRINCIPAL: the principal; see Representing workforce identity pool users in IAM policies.

In the example that follows, the command grants the Storage Admin (roles/storage.admin) to all identities within the group GROUP_ID:

gcloud projects add-iam-policy-binding my-project \
    --role="roles/storage.admin" \
    --member="principalSet://iam.googleapis.com/locations/global/workforcePools/WORKFORCE_POOL_ID/group/GROUP_ID"

For more information about the principal format, see Represent workforce identity pool users in IAM policies.

What's next

• Obtain short-lived credentials for workforce identity federation
• Manage workforce identity pool providers
• Delete workforce identity federation users and their data
• Learn which Google Cloud products support workforce identity federation
• Set up user access to console (federated)