Personnaliser une configuration OAuth pour activer IAP

Ce document explique quand et comment personnaliser une configuration OAuth pour Identity-Aware Proxy (IAP).

IAP utilise un client OAuth géré par Google pour authentifier les utilisateurs.

Le client OAuth géré par Google limite l'accès aux utilisateurs de la même organisation lorsqu'ils accèdent à des applications compatibles avec les achats intégrés via un navigateur.

Quand utiliser une configuration OAuth personnalisée

Vous devez utiliser une configuration OAuth personnalisée pour effectuer les opérations suivantes:

  • Autoriser l'accès aux applications compatibles avec l'IAP pour les utilisateurs externes à l'organisation.
  • Pour afficher les informations sur votre propre marque lors de l'authentification.
  • Pour activer l'accès programmatique à votre application.

Lorsque vous personnalisez votre configuration OAuth, vous devez configurer l'écran de consentement OAuth. Pour cela, les informations sur la marque de votre application doivent être soumises au processus de validation de Google. Pour en savoir plus sur le processus de validation, consultez la section Configurer votre écran de consentement OAuth.

Vous êtes responsable de la création et de la gestion des identifiants d'un client OAuth personnalisé. Cela inclut le stockage sécurisé du code secret du client et son partage avec les utilisateurs autorisés si nécessaire.

Comparaison entre le client OAuth géré par Google et le client OAuth personnalisé

Les clients OAuth gérés par Google ne peuvent pas accéder par programmation aux applications protégées par IAP. Toutefois, les applications protégées par IAP qui utilisent le client OAuth géré par Google peuvent toujours être consultées par programmation à l'aide d'un client OAuth distinct configuré via le paramètre programmatic_clients ou d'un JWT de compte de service.

Le tableau suivant compare le client OAuth géré par Google et un client OAuth personnalisé.

Client OAuth géré par Google Client OAuth personnalisé
Utilisateurs Interne uniquement Partenaires internes et externes
Brand Google Cloud marque Marque appartenant au client
Configuration OAuth Google configuré Configuration client
Identifiants OAuth Géré par Google Géré par le client
Accès des applications Parcours dans le navigateur uniquement Flux du navigateur et accès programmatique
.

Activer l'IAP à l'aide d'une configuration client OAuth personnalisée

Les sections suivantes expliquent comment activer IAP à l'aide d'une configuration de client OAuth personnalisée pour différentes ressources.

App Engine

Console

Dynamic include file

If you haven't configured your project's OAuth consent screen, you'll be prompted to do so. To configure your OAuth consent screen, see Setting up your OAuth consent screen.

Setting up IAP access

  1. Go to the Identity-Aware Proxy page.
    Go to the Identity-Aware Proxy page
  2. Select the project you want to secure with IAP.
  3. Select the checkbox next to the resource you want to grant access to.
  4. On the right side panel, click Add principal.
  5. In the Add principals dialog that appears, enter the email addresses of groups or individuals who should have the IAP-secured Web App User role for the project.

    The following kinds of principals can have this role:

    • Google Account: user@gmail.com
    • Google Group: admins@googlegroups.com
    • Service account: server@example.gserviceaccount.com
    • Google Workspace domain: example.com

    Make sure to add a Google Account that you have access to.

  6. Select Cloud IAP > IAP-secured Web App User from the Roles drop-down list.
  7. Click Save.

Turning on IAP

  1. On the Identity-Aware Proxy page, under APPLICATIONS, find the application you want to restrict access to. To turn on IAP for a resource,
  2. In the Turn on IAP window that appears, click Turn On to confirm that you want IAP to secure your resource. After you turn on IAP, it requires login credentials for all connections to your load balancer. Only accounts with the IAP-Secured Web App User role on the project will be given access.

gcloud

Before you set up your project and IAP, you need an up-to-date version of gcloud CLI. For instructions on how to install the gcloud CLI, see Install the gcloud CLI.

  1. To authenticate, use the Google Cloud CLI and run the following command. 
    gcloud auth login
  2. To sign in, follow the URL that appears.
  3. After you sign in, copy the verification code that appears and paste it in the command line.
  4. Run the following command to specify the project that contains the resource that you want to protect with IAP. 
    gcloud config set project PROJECT_ID
  5. Follow the instructions in Creating OAuth clients for IAP to configure the OAuth consent screen and create the OAuth client.
  6. Save the OAuth client ID and secret.
  7. To enable IAP, run the following command. 
    gcloud iap web enable \
    --oauth2-client-id=CLIENT_ID \
    --oauth2-client-secret=CLIENT_SECRET \
    --resource-type=app-engine

After you enable IAP, you can use the gcloud CLI to modify the IAP access policy using the IAM role roles/iap.httpsResourceAccessor. Learn more about managing roles and permissions.

API

  1. Follow the instructions in Creating OAuth clients for IAP to configure the OAuth consent screen and create the OAuth client.

  2. Save the OAuth client ID and secret.

  3. Run the following command to prepare a settings.json file. 

    cat << EOF > settings.json
{
"iap":
  {
    "enabled": true,
    "oauth2ClientId": "CLIENT_ID",
    "oauth2ClientSecret":" CLIENT_SECRET"
  }
}
EOF

  4. Run the following command to enable IAP. 

    curl -X PATCH \
-H "Authorization: Bearer $(gcloud auth application-default print-access-token)" \
-H "Accept: application/json" \
-H "Content-Type: application/json" \
-d @settings.json \
"https://appengine.googleapis.com/v1/apps/PROJECT_ID?updateMask=iap"

After you enable IAP, you can use the Google Cloud CLI to modify the IAP access policy using the IAM role roles/iap.httpsResourceAccessor. Learn more about managing roles and permissions.

Compute Engine

Console

If you haven't configured your project's OAuth consent screen, you'll be prompted to do so. To configure your OAuth consent screen, see Setting up your OAuth consent screen.

If you are running GKE clusters version 1.24 or later, you can configure IAP and GKE by using the Kubernetes Gateway API. To do so, complete the following steps and then follow the instructions in Configure IAP. Do not configure BackendConfig.

Setting up IAP access

  1. Go to the Identity-Aware Proxy page.
    Go to the Identity-Aware Proxy page
  2. Select the project you want to secure with IAP.

  3. Select the checkbox next to the resource you want to grant access to.

    If you don't see a resource, ensure that the resource is created and that the BackendConfig Compute Engine ingress controller is synced.

    To verify that the backend service is available, run the following gcloud command:

    gcloud compute backend-services list
  4. On the right side panel, click Add principal.
  5. In the Add principals dialog that appears, enter the email addresses of groups or individuals who should have the IAP-secured Web App User role for the project.

    The following kinds of principals can have this role:

    • Google Account: user@gmail.com
    • Google Group: admins@googlegroups.com
    • Service account: server@example.gserviceaccount.com
    • Google Workspace domain: example.com

    Make sure to add a Google Account that you have access to.

  6. Select Cloud IAP > IAP-secured Web App User from the Roles drop-down list.
  7. Click Save.

Turning on IAP

  1. On the Identity-Aware Proxy page, under APPLICATIONS, find the load balancer that serves the instance group you want to restrict access to. To turn on IAP for a resource,
    To enable IAP:
    • At least one protocol in the load balancer frontend configuration must be HTTPS. Learn about setting up a load balancer.
    • You need the compute.backendServices.update, clientauthconfig.clients.create, and clientauthconfig.clients.getWithSecret permissions. These permissions are granted by roles, such as the Project Editor role. To learn more, see Managing access to IAP-secured resources.
  2. In the Turn on IAP window that appears, click Turn On to confirm that you want IAP to secure your resource. After you turn on IAP, it requires login credentials for all connections to your load balancer. Only accounts with the IAP-Secured Web App User role on the project will be given access.

gcloud

Before you set up your project and IAP, you need an up-to-date version of the gcloud CLI. For instructions on how to install the gcloud CLI, see Install the gcloud CLI.

  1. To authenticate, use the Google Cloud CLI and run the following command. 
    gcloud auth login
  2. To sign in, follow the URL that appears.
  3. After you sign in, copy the verification code that appears and paste it in the command line.
  4. Run the following command to specify the project that contains the resource that you want to protect with IAP. 
    gcloud config set project PROJECT_ID
  5. Follow the instructions in Creating OAuth clients for IAP. to configure the OAuth consent screen and create the OAuth client.
  6. Save the OAuth client ID and secret.
  7. To enable IAP, run either the globally or regionally scoped command.

    Global scope 
    gcloud compute backend-services update BACKEND_SERVICE_NAME \
    --global \
    --iap=enabled,oauth2-client-id=CLIENT_ID,oauth2-client-secret=CLIENT_SECRET
     Regional scope 
    gcloud compute backend-services update BACKEND_SERVICE_NAME \
    --region REGION_NAME \
    --iap=enabled,oauth2-client-id=CLIENT_ID,oauth2-client-secret=CLIENT_SECRET

After you enable IAP, you can use the gcloud CLI to modify the IAP access policy using the IAM role roles/iap.httpsResourceAccessor. Learn more about managing roles and permissions.

API

  1. Follow the instructions in Creating OAuth clients for IAP to configure the OAuth consent screen and create the OAuth client.

  2. Save the OAuth client ID and secret.

  3. Run the following command to prepare a settings.json file. 

    cat << EOF > settings.json
{
"iap":
  {
    "enabled": true,
    "oauth2ClientId": "CLIENT_ID",
    "oauth2ClientSecret": "CLIENT_SECRET"
  }
}
EOF

  4. Run the following command to enable IAP. 

    curl -X PATCH \
-H "Authorization: Bearer $(gcloud auth application-default print-access-token)" \
-H "Accept: application/json" \
-H "Content-Type: application/json" \
-d @settings.json \
"https://compute.googleapis.com/compute/v1/projects/PROJECT_ID/REGION/backendServices/BACKEND_SERVICE_NAME"

After you enable IAP, you can use the gcloud CLI to modify the IAP access policy using the IAM role roles/iap.httpsResourceAccessor. Learn more about managing roles and permissions.

Cloud Run

Console

If you haven't configured your project's OAuth consent screen, you're prompted to do so. To configure your OAuth consent screen, see Setting up your OAuth consent screen

Setting up IAP access

  1. Open the Identity-Aware Proxy page.
    Go to Identity-Aware Proxy
  2. Select the project you want to secure with IAP.
  3. Under Applications, select the checkbox next to the load balancer backend service to which you want to add members.
  4. On the right side panel, click Add member.

  5. In the Add members dialog, enter the accounts of groups or individuals who should have the IAP-secured Web App User role for the project. The following kinds of accounts can be members:

    • Google Account: user@gmail.com - This can also be a Google Workspace account, such as user@google.com or some other Google Workspace domain.
    • Google Group: admins@googlegroups.com
    • Service account: server@example.gserviceaccount.com
    • Google Workspace domain: example.com

  6. Select Cloud IAP > IAP-secured Web App User from the Roles list.

  7. Click Save.

Turning on IAP

  1. On the IAP page, under Applications, find the load balancer backend service to which you want to restrict access. Click the IAP toggle to enable IAP on a resource.
  2. In the Turn on IAP window that appears, click Turn On to confirm that you want IAP to secure your resource. After you turn on IAP, it requires login credentials for all connections to your load balancer. Only accounts with the IAP-Secured Web App User role on the project will be given access.

  3. To authorize IAP to send traffic to the backend Cloud Run service, follow the instructions at Add principals to a service to add the following principle and role.

    • Principal: service-[PROJECT-NUMBER]@gcp-sa-iap.iam.gserviceaccount.com
    • Role: Cloud Run Invoker

gcloud

  1. Follow the instructions in Creating OAuth clients for IAP to configure the OAuth consent screen and create the OAuth client.
  2. Save the OAuth client ID and secret.
  3. If you have not previously done so, create a service account by running the following command. If you previously created a service account, running the command does not create duplicate service accounts. 
    gcloud beta services identity create \
    --service=iap.googleapis.com --project=PROJECT_ID
  4. Grant the invoker permission to the service account, created in the previous step, by running the following command. 
    gcloud run services add-iam-policy-binding SERVICE-NAME \
    --member='serviceAccount:service-PROJECT-NUMBER@gcp-sa-iap.iam.gserviceaccount.com' \
    --role='roles/run.invoker'

  5. Enable IAP by running either the globally or regionally scoped command, depending on whether your load balancer backend service is global or regional. Use the OAuth client ID and secret from the previous step.

    Global scope 

    gcloud compute backend-services update BACKEND_SERVICE_NAME \
    --global \
    --iap=enabled,oauth2-client-id=CLIENT_ID,oauth2-client-secret=CLIENT_SECRET

    Regional scope 

    gcloud compute backend-services update BACKEND_SERVICE_NAME \
    --region REGION_NAME \
    --iap=enabled,oauth2-client-id=CLIENT_ID,oauth2-client-secret=CLIENT_SECRET
    Replace the following:

    • BACKEND_SERVICE_NAME: the name of the backend service.
    • CLIENT_ID: the OAuth client ID, from the previous step.
    • CLIENT_SECRET: the OAuth client secret, from the previous step.
    • REGION_NAME: the region in which you want to enable IAP.

After you enable IAP, you can use the Google Cloud CLI to modify the IAP access policy using the Identity and Access Management role roles/iap.httpsResourceAccessor. See Managing roles and permissions for more information.

Google Kubernetes Engine

Console

If you haven't configured your project's OAuth consent screen, you'll be prompted to do so. To configure your OAuth consent screen, see Setting up your OAuth consent screen.

If you are running GKE clusters version 1.24 or later, you can configure IAP and GKE by using the Kubernetes Gateway API. To do so, complete the following steps and then follow the instructions in Configure IAP. Do not configure BackendConfig.

Setting up IAP access

  1. Go to the Identity-Aware Proxy page.
    Go to the Identity-Aware Proxy page
  2. Select the project you want to secure with IAP.

  3. Select the checkbox next to the resource you want to grant access to.

    If you don't see a resource, ensure that the resource is created and that the BackendConfig Compute Engine ingress controller is synced.

    To verify that the backend service is available, run the following gcloud command:

    gcloud compute backend-services list
  4. On the right side panel, click Add principal.
  5. In the Add principals dialog that appears, enter the email addresses of groups or individuals who should have the IAP-secured Web App User role for the project.

    The following kinds of principals can have this role:

    • Google Account: user@gmail.com
    • Google Group: admins@googlegroups.com
    • Service account: server@example.gserviceaccount.com
    • Google Workspace domain: example.com

    Make sure to add a Google Account that you have access to.

  6. Select Cloud IAP > IAP-secured Web App User from the Roles drop-down list.
  7. Click Save.

Turning on IAP

  1. On the Identity-Aware Proxy page, under APPLICATIONS, find the load balancer that serves the instance group you want to restrict access to. To turn on IAP for a resource,
    To enable IAP:
    • At least one protocol in the load balancer frontend configuration must be HTTPS. Learn about setting up a load balancer.
    • You need the compute.backendServices.update, clientauthconfig.clients.create, and clientauthconfig.clients.getWithSecret permissions. These permissions are granted by roles, such as the Project Editor role. To learn more, see Managing access to IAP-secured resources.
  2. In the Turn on IAP window that appears, click Turn On to confirm that you want IAP to secure your resource. After you turn on IAP, it requires login credentials for all connections to your load balancer. Only accounts with the IAP-Secured Web App User role on the project will be given access.

GKE

Configure the BackendConfig

If you are running GKE clusters version 1.24 or later, you can configure IAP and GKE by using the Kubernetes Gateway API. See Configure IAP for instructions.

  1. Follow the instructions in Creating OAuth clients for IAP to configure the OAuth consent screen and create the OAuth client.

  2. Create a Kubernetes Secret to wrap the OAuth client. 

    kubectl create secret generic MY_SECRET --from-literal=client_id=CLIENT_ID \
  --from-literal=client_secret=CLIENT_SECRET
    Replace the following:

    • MY_SECRET: The name of the secret to create
    • CLIENT_ID: The OAuth client ID
    • CLIENT_SECRET: The OAuth client secret

    You should receive confirmation, like the following output, that the Secret was successfully created: 

    secret "MY_SECRET" created

  3. Add the OAuth credentials to the BackendConfig. 

    apiVersion: cloud.google.com/v1
kind: BackendConfig
metadata:
  name: CONFIG_DEFAULT
  namespace: my-namespace
spec:
iap:
  enabled: true
  oauthclientCredentials:
    secretName: MY_SECRET

  4. Enable IAP by associating Service ports with your BackendConfig. See Associating BackendConfig with your Ingress. One way to make this association is to make all ports for the service default to your BackendConfig, which you can do by adding the following annotation to your Service resource: 

    metadata:
  annotations:
      beta.cloud.google.com/backend-config: '{"default": "CONFIG_DEFAULT"}}'

After you enable IAP, you can use the gcloud CLI to modify the IAP access policy using the IAM role roles/iap.httpsResourceAccessor. Learn more about managing roles and permissions.

Troubleshooting

If the secretName you referenced doesn't exist or isn't structured properly, one of the following error messages will display:

  • BackendConfig default/config-default is not valid: error retrieving secret "foo": secrets "foo" not found. To resolve this error, make sure that you've created the Kubernetes Secret correctly as described in step 2.

  • BackendConfig default/config-default is not valid: secret "foo" missing client_secret data. To resolve this error, make sure that you've created the OAuth credentials correctly. Also, make sure that you referenced the correct client_id and client_secret keys.