Google Cloud auth method (API)

This is the API documentation for the Vault Google Cloud auth method. To learn more about the usage and operation, see the Vault Google Cloud method documentation.

This documentation assumes the plugin method is mounted at the /auth/gcp path in Vault. Since it is possible to enable auth methods at any location, please update your API calls accordingly.

Configure

Configures the credentials required for the plugin to perform API calls to Google Cloud. These credentials will be used to query the status of IAM entities and get service account or other Google public certificates to confirm signed JWTs passed in during login.

Method	Path
POST	/auth/gcp/config

Parameters

• credentials (string: "") - A JSON string containing the contents of a GCP service account credentials file. The service account associated with the credentials file must have the following permissions. If this value is empty, Vault will try to use Application Default Credentials from the machine on which the Vault server is running.

• iam_alias (string: "role_id") - Must be either unique_id or role_id. If unique_id is specified, the service account's unique ID will be used for alias names during login. If role_id is specified, the ID of the Vault role will be used. Only used if role type is iam.

• iam_metadata (string: "default") - The metadata to include on the token returned by the login endpoint. This metadata will be added to both audit logs, and on the iam_alias. By default, it includes project_id, role, service_account_id, and service_account_email. To include no metadata, set to "" via the CLI or [] via the API. To use only particular fields, select the explicit fields. To restore to defaults, send only a field of default. Only select fields that will have a low rate of change for your iam_alias because each change triggers a storage write and can have a performance impact at scale. Only used if role type is iam.

• gce_alias (string: "role_id") - Must be either instance_id or role_id. If instance_id is specified, the GCE instance ID will be used for alias names during login. If role_id is specified, the ID of the Vault role will be used. Only used if role type is gce.

• gce_metadata (string: "default") - The metadata to include on the token returned by the login endpoint. This metadata will be added to both audit logs, and on the gce_alias. By default, it includes instance_creation_timestamp, instance_id, instance_name, project_id, project_number, role, service_account_id, service_account_email, and zone. To include no metadata, set to "" via the CLI or [] via the API. To use only particular fields, select the explicit fields. To restore to defaults, send only a field of default. Only select fields that will have a low rate of change for your gce_alias because each change triggers a storage write and can have a performance impact at scale. Only used if role type is gce.

• custom_endpoint (map<string|string>: <optional>) - Specifies overrides to service endpoints used when making API requests. This allows specific requests made during authentication to target alternative service endpoints for use in Private Google Access environments.

  Overrides are set at the subdomain level using the following keys:

  • api - Replaces the service endpoint used in API requests to https://www.googleapis.com.

  • iam - Replaces the service endpoint used in API requests to https://iam.googleapis.com.

  • crm - Replaces the service endpoint used in API requests to https://cloudresourcemanager.googleapis.com.

  • compute - Replaces the service endpoint used in API requests to https://compute.googleapis.com.

  The endpoint value provided for a given key has the form of scheme://host:port. The scheme:// and :port portions of the endpoint value are optional.

Sample payload

{
  "credentials": "{ \"type\": \"service_account\", \"project_id\": \"project-123456\", ...}"
}

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/auth/gcp/config

Read config

Returns the configuration, if any, including credentials.

Method	Path
GET	/auth/gcp/config

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    http://127.0.0.1:8200/v1/auth/gcp/config

Sample response

{
  "data": {
    "client_email": "[e-mail]",
    "client_id": "123456789101112131415",
    "private_key_id": "97fd7ba59a96e1f3830296aedb4f50879e4d5382",
    "project_id": "project-123456"
  }
}

Create/Update role

Registers a role in the method. Role types have specific entities that can perform login operations against this endpoint. Constraints specific to the role type must be set on the role. These are applied to the authenticated entities attempting to login.

Method	Path
POST	/auth/gcp/role/:name

Parameters

• name (string: <required>) - The name of the role.

• type (string: <required>) - The type of this role. Certain fields correspond to specific roles and will be rejected otherwise. Please see below for more information.

• bound_service_accounts (array: <required for iam>) - An array of service account emails or IDs that login is restricted to, either directly or through an associated instance. If set to *, all service accounts are allowed (you can bind this further using bound_projects.)

• bound_projects (array: []) - An array of GCP project IDs. Only entities belonging to this project can authenticate under the role.

• add_group_aliases (bool: false) - If true, any auth token generated under this token will have associated group aliases, namely project-$PROJECT_ID, folder-$PROJECT_ID, and organization-$ORG_ID for the entities project and all its folder or organization ancestors. This requires Vault to have IAM permission resourcemanager.projects.get.

@include 'tokenfields.mdx'

iam-only parameters

The following parameters are only valid when the role is of type "iam":

• max_jwt_exp (string: "15m") - The number of seconds past the time of authentication that the login param JWT must expire within. For example, if a user attempts to login with a token that expires within an hour and this is set to 15 minutes, Vault will return an error prompting the user to create a new signed JWT with a shorter exp. The GCE metadata tokens currently do not allow the exp claim to be customized.

• allow_gce_inference (bool: true) - A flag to determine if this role should allow GCE instances to authenticate by inferring service accounts from the GCE identity metadata token.

gce-only parameters

The following parameters are only valid when the role is of type "gce":

• bound_zones (array: []): The list of zones that a GCE instance must belong to in order to be authenticated. If bound_instance_groups is provided, it is assumed to be a zonal group and the group must belong to this zone.

• bound_regions (array: []): The list of regions that a GCE instance must belong to in order to be authenticated. If bound_instance_groups is provided, it is assumed to be a regional group and the group must belong to this region. If bound_zones are provided, this attribute is ignored.

• bound_instance_groups (array: []): The instance groups that an authorized instance must belong to in order to be authenticated. If specified, either bound_zones or bound_regions must be set too.

• bound_labels (array: []): A comma-separated list of GCP labels formatted as "key:value" strings that must be set on authorized GCE instances. Because GCP labels are not currently ACL'd, we recommend that this be used in conjunction with other restrictions.

Sample payload

Example iam role:

{
  "type": "iam",
  "project_id": "project-123456",
  "policies": ["prod"],
  "ttl": "30m",
  "max_ttl": "24h",
  "max_jwt_exp": "5m",
  "bound_service_accounts": ["[e-mail]"]
}

Example gce role:

{
  "type": "gce",
  "project_id": "project-123456",
  "policies": ["prod"],
  "bound_zones": ["us-east1-b", "eu-west2-a"],
  "ttl": "30m",
  "max_ttl": "24h",
  "bound_service_accounts": ["[e-mail]"]
}

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/auth/gcp/role/my-role

Edit service accounts on IAM role

Edit service accounts for an existing IAM role in the method. This allows you to add or remove service accounts from the list of service accounts on the role.

Method	Path
POST	/auth/gcp/role/:name/service-accounts

Parameters

• name (string: <required>) - The name of an existing iam type role. This will return an error if role is not an iam type role.

• add (array: []) - The list of service accounts to add to the role's service accounts.

• remove (array: []) - The list of service accounts to remove from the role's service accounts.

Sample payload

{
  "add": ["[e-mail]", "123456789"],
  "remove": ["[e-mail]"]
}

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/auth/gcp/role/my-role

Edit labels on GCE role

Edit labels for an existing GCE role in the backend. This allows you to add or remove labels (keys, values, or both) from the list of keys on the role.

Method	Path
POST	/auth/gcp/role/:name/labels

Parameters

• name (string: <required>) - The name of an existing gce role. This will return an error if role is not a gce type role.

• add (array: []) - The list of key:value labels to add to the GCE role's bound labels.

• remove (array: []) - The list of label keys to remove from the role's bound labels. If any of the specified keys do not exist, no error is returned (idempotent).

Sample payload

{
  "add": ["foo:bar", "env:dev", "key:value"],
  "remove": ["key1", "key2"]
}

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/auth/gcp/role/my-role

Read role

Returns the previously registered role configuration.

Method	Path
GET	/auth/gcp/role/:name

Parameters

• name (string: <required>) - The name of the role to read.

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    http://127.0.0.1:8200/v1/auth/gcp/role/my-role

Sample response

{
  "data": {
    "bound_labels": {
      "env": "dev",
      "foo": "bar",
      "key": "value"
    },
    "bound_service_accounts": ["[e-mail]"],
    "bound_zones": ["eu-west2-a", "us-east1-b"],
    "gce_alias": "instance_id",
    "max_ttl": 86400,
    "policies": ["prod"],
    "project_id": "project-123456",
    "role_id": "6bbfab2b-ca32-6044-4829-4515728d87b1",
    "type": "gce",
    "ttl": 1800
  }
}

List roles

Lists all the roles that are registered with the plugin.

Method	Path
LIST	/auth/gcp/roles

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    --request LIST \
    http://127.0.0.1:8200/v1/auth/gcp/roles

Sample response

{
  "data": {
    "keys": ["my-role", "my-other-role"]
  }
}

Delete role

Deletes the previously registered role.

Method	Path
DELETE	/auth/gcp/role/:role

Parameters

• role (string: <required>) - The name of the role to delete.

Sample request

$ curl \
    --header "X-Vault-Token: ..." \
    --request DELETE \
    http://127.0.0.1:8200/v1/auth/gcp/role/my-role

Login

Login to retrieve a Vault token. This endpoint takes a signed JSON Web Token (JWT) and a role name for some entity. It verifies the JWT signature with Google Cloud to authenticate that entity and then authorizes the entity for the given role.

Method	Path
POST	/auth/gcp/login

Sample payload

• role (string: <required>) - The name of the role against which the login is being attempted.

• jwt (string: <required>) - A Signed JSON Web Token.

  • For iam type roles, this is a JWT signed with the signJwt method or a self-signed JWT.

  • For gce type roles, this is an identity metadata token.

Sample payload

{
  "role": "my-role",
  "jwt": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..."
}

Sample request

$ curl \
    --request POST \
    --data @payload.json \
    http://127.0.0.1:8200/v1/auth/gcp/login

Sample response

{
  "auth": {
    "client_token": "f33f8c72-924e-11f8-cb43-ac59d697597c",
    "accessor": "0e9e354a-520f-df04-6867-ee81cae3d42d",
    "policies": ["default", "dev", "prod"],
    "metadata": {
      "project_id": "my-project",
      "role": "my-role",
      "service_account_email": "[e-mail]",
      "service_account_id": "111111111111111111111"
    },
    "lease_duration": 2764800,
    "renewable": true
  }
}