Skip to main content
Version: 19.x (unreleased)

Database Access with Cloud Spanner

Report an IssueView as Markdown

Teleport can provide secure access to Cloud Spanner via the Teleport Database Service. This allows for fine-grained access control through Teleport's RBAC.

In this guide, you will:

  1. Configure your Cloud Spanner database with a service account.
  2. Add the database to your Teleport cluster.
  3. Connect to the database via Teleport.

How it works​

The Teleport Database Service uses IAM authentication to communicate with Spanner. When a user connects to the database via Teleport, the Teleport Database Service obtains Google Cloud credentials and authenticates to Google Cloud as an IAM principal with permissions to access the database.

Self-Hosted Teleport Architecture for Cloud Spanner Access

Prerequisites​

  • A running Teleport cluster. If you want to get started with Teleport, sign up for a free trial or set up a demo environment.

  • The tctl and tsh clients.

    Installing tctl and tsh clients

    1. Determine the version of your Teleport cluster. The tctl and tsh clients must be at most one major version behind your Teleport cluster version. Send a GET request to the Proxy Service at /v1/webapi/find and use a JSON query tool to obtain your cluster version. Replace teleport.example.com:443 with the web address of your Teleport Proxy Service:

      TELEPORT_DOMAIN=teleport.example.com:443
      TELEPORT_VERSION="$(curl -s https://$TELEPORT_DOMAIN/v1/webapi/find | jq -r '.server_version')"

    2. Follow the instructions for your platform to install tctl and tsh clients:

      Download the signed macOS .pkg installer for Teleport, which includes the tctl and tsh clients:

      curl -O https://cdn.teleport.dev/teleport-${TELEPORT_VERSION?}.pkg

      In Finder double-click the pkg file to begin installation.

      danger

      Using Homebrew to install Teleport is not supported. The Teleport package in Homebrew is not maintained by Teleport and we can't guarantee its reliability or security.

  • A Google Cloud account
  • A Cloud Spanner instance and database
  • A host to run the Teleport Database Service (for example, a Compute Engine instance) with outbound HTTPS access to spanner.googleapis.com:443
  • To check that you can connect to your Teleport cluster, sign in with tsh login, then verify that you can run tctl commands using your current credentials. For example, run the following command, assigning teleport.example.com to the domain name of the Teleport Proxy Service in your cluster and [email protected] to your Teleport username: 
    tsh login --proxy=teleport.example.com --user=[email protected]
    tctl status
    Cluster  teleport.example.com
    Version  19.0.0-dev
    CA pin   sha256:abdc1245efgh5678abdc1245efgh5678abdc1245efgh5678abdc1245efgh5678
    If you can connect to the cluster and run the tctl status command, you can use your current credentials to run subsequent tctl commands from your workstation. If you host your own Teleport cluster, you can also run tctl commands on the computer that hosts the Teleport Auth Service for full permissions.

Step 1/6. Create service accounts​

Teleport requires two types of Google Cloud service accounts:

  • Database Service: a single service account used by the Teleport Database Service to access Google Cloud and impersonate database user service accounts
  • Database user: one or more service accounts impersonated per connection to represent database users

For example, in the following steps, we create teleport-db-service (Database Service service account) and spanner-user (a Database user service account).

Create the Database Service account​

This account is used by the Teleport Database Service to access Google Cloud and impersonate the database user account.

  1. Navigate to IAM & Admin → Service Accounts.
  2. Click Create Service Account.
  3. Set the name to teleport-db-service.
  4. Skip optional steps and click Done. You will grant permissions later.

Create the database user account​

This account represents a database user. Teleport users specify this name when connecting.

  1. Navigate to IAM & Admin → Service Accounts.
  2. Click Create Service Account.
  3. Set the name to spanner-user.
  4. Skip optional steps and click Done. You will grant permissions later. =

Step 2/6. Grant permissions​

Grant the database user account access to Spanner, then allow the Database Service account to impersonate the database user account.

Grant Spanner access​

  1. Navigate to Spanner → Instances
  2. Select your instance
  3. Click Permissions → Add Principal
  4. Enter the spanner-user service account
  5. Assign Cloud Spanner Database User
  6. Click Save
Custom Spanner role

The Cloud Spanner Database User role is predefined. You can create custom IAM roles to further restrict access if needed.

Allow service account impersonation​

Grant the Database Service account permission to impersonate the database user account.

  1. Navigate to IAM & Admin → Service Accounts
  2. Select spanner-user
  3. Open the Permissions tab
  4. Click Grant Access
  5. Add the teleport-db-service account
  6. Assign Service Account Token Creator
  7. Click Save

Checkpoint: Verify GCP permissions

Confirm that the Database Service account can impersonate the database user account.

Step 3/6. Install and configure the Teleport Database Service​

To install Teleport binaries on your Linux server, the recommended installation method is the cluster install script. It will select the correct version, edition, and installation mode for your cluster.

  1. Assign teleport.example.com:443 to your Teleport cluster hostname and port, but not the scheme (https://).

  2. Run your cluster's install script:

    curl "https://teleport.example.com:443/scripts/install.sh" | sudo bash

The Database Service requires a valid join token to join your Teleport cluster. Run the following tctl command and save the token output in /tmp/token on the server that will run the Database Service:

tctl tokens add --type=db --format=text
abcd123-insecure-do-not-use-this

Provide the following information and then generate a configuration file for the Teleport Database Service:

  • example.teleport.sh:443 The host and port of your Teleport Proxy Service or cloud-hosted Teleport Enterprise site.
  • project-id The GCP project ID. You can normally see it in the organization view at the top of the GCP dashboard.
  • instance-id The name of your Cloud Spanner instance.
sudo teleport db configure create \  -o file \  --name=spanner-example \  --protocol=spanner \  --labels=env=dev \  --token=/tmp/token \  --uri=spanner.googleapis.com:443 \  --proxy=example.teleport.sh:443 \  --gcp-project-id=project-id \  --gcp-instance-id=instance-id

Step 4/6. Configure GCP credentials​

The Teleport Database Service must have credentials for the "teleport-db-service" GCP service account.

If the Teleport Database Service is hosted on a GCE instance, you can change the attached service account. For non-GCE deployments of Teleport, we recommend using workload identity.

Using service account keys (insecure)

Alternatively, go to that service account's Keys tab and create a new key:

Service Account Keys

Make sure to choose JSON format:

Service Account New Key

Save the file. Set the GOOGLE_APPLICATION_CREDENTIALS environment variable to point to the JSON credentials file you downloaded earlier. For example, if you use systemd to start teleport, then you should edit the service's EnvironmentFile to include the env var:

echo 'GOOGLE_APPLICATION_CREDENTIALS=/path/to/credentials.json' | sudo tee -a /etc/default/teleport
warning

A service account key can be a security risk - we only describe using a key in this guide for simplicity. We do not recommend using service account keys in production. See authentication in the Google Cloud documentation for more information about service account authentication methods.

Step 5/6. Start the Teleport Database Service​

Configure the Teleport Database Service to start automatically when the host boots up by creating a systemd service for it. The instructions depend on how you installed the Teleport Database Service.

On the host where you will run the Teleport Database Service, enable and start Teleport:

sudo systemctl enable teleport
sudo systemctl start teleport

You can check the status of the Teleport Database Service with systemctl status teleport and view its logs with journalctl -fu teleport.

Checkpoint: Verify database availability

Confirm that the Spanner database appears in Teleport.

Step 6/6. Connect using the service account​

In this step, you will create a Teleport user with access to the Spanner database, connect using the database user service account, and optionally remove stored credentials when you are done.

tip

To modify an existing user to provide access to the Database Service, see Database Access Controls

Create a local Teleport user with the built-in access role:

tctl users add \  --roles=access \  --db-users="*" \  --db-names="*" \  alice
FlagDescription
--rolesList of roles to assign to the user. The builtin access role allows them to connect to any database server registered with Teleport.
--db-usersList of database usernames the user will be allowed to use when connecting to the databases. A wildcard allows any user.
--db-namesList of logical databases (aka schemas) the user will be allowed to connect to within a database server. A wildcard allows any database.
warning

Database names are only enforced for PostgreSQL, MongoDB, and Cloud Spanner databases.

For more detailed information about database access controls and how to restrict access see RBAC documentation.

Log in to your Teleport cluster as the new user that you just created:

tsh login --proxy=example.teleport.sh --user=example-user

Connect using the service account name (without the domain suffix): (Note: --db-name here refers to the specific database ID within your Spanner instance.)

tsh db connect --db-user=spanner-user --db-name=database-name spanner-example

You should now have an authenticated connection using the impersonated service account.

To remove credentials:

tsh db logout spanner-example

To remove all database credentials:

tsh db logout

Troubleshooting​

Could not find default credentials​

This error can come from either your client application or Teleport.

For a client application, ensure that you disable GCP credential loading. Your client should not attempt to load credentials because GCP credentials will be provided by the Teleport Database Service.

If you see the credentials error message in the Teleport Database Service logs (at DEBUG log level), then the Teleport Database Service does not have GCP credentials configured correctly.

If you are using a service account key, then ensure that the environment variable GOOGLE_APPLICATION_CREDENTIALS=/path/to/credentials.json is set and restart your Teleport Database Service to ensure that the env var is available to teleport. For example, if your Teleport Database Service runs as a systemd service:

echo 'GOOGLE_APPLICATION_CREDENTIALS=/path/to/credentials.json' | sudo tee -a /etc/default/teleport
sudo systemctl restart teleport

See authentication in the Google Cloud documentation for more information about service account authentication methods.

Next steps​