No More Backdoors: Know Who Has Access to What, Right Now
Jun 13
Virtual
Register Today
Teleport logoTry For Free
Fork me on GitHub

Teleport

Database Access with Redshift Serverless on AWS

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

In this guide, you will:

  1. Configure your Amazon Redshift Serverless database with IAM authentication.
  2. Add the database to your Teleport cluster.
  3. Connect to the database via Teleport

This guide will help you to:

  • Set up Teleport to access your Amazon Redshift Serverless workgroups.
  • Connect to your databases through Teleport.

How it works

The Teleport Database Service uses IAM authentication to communicate with Redshift Serverless. When a user connects to the database via Teleport, the Teleport Database Service obtains AWS credentials and authenticates to AWS as an IAM principal with permissions to manage the database.

This guide shows how to enroll a single Amazon Redshift Serverless database through the Teleport Database Service. For a more scalable approach, learn how to configure the Teleport Discovery Service to automatically enroll all AWS databases in your infrastructure.

Prerequisites

  • A running Teleport cluster version 16.0.0 or above. If you want to get started with Teleport, sign up for a free trial or set up a demo environment.

  • The tctl admin tool and tsh client tool.

    Visit Installation for instructions on downloading tctl and tsh.

  • AWS account with a Redshift Serverless configuration and permissions to create and attach IAM policies.
  • Command-line client psql installed and added to your system's PATH environment variable.
  • A host where you will run the Teleport Database Service. This guide assumes an EC2 instance, and provides a corresponding example of access control.
  • 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. tctl is supported on macOS and Linux machines. For example:
    tsh login --proxy=teleport.example.com --user=[email protected]
    tctl status

    Cluster teleport.example.com

    Version 16.0.0

    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 1/4. Create an IAM Role for user access

Create an AWS IAM role to provide user access to Redshift Serverless. This role will be granted to Teleport users via a corresponding Teleport role. In this guide we will use the example name teleport-redshift-serverless-access.

Under Trusted entity type choose "Custom trust policy". Edit the trust policy to allow the IAM role generated in the previous step to assume this role, so that the Teleport node can use the permissions granted by this role to access databases:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "Statement1",
            "Effect": "Allow",
            "Principal": {
                "AWS": "arn:aws:iam::abcd1234-this-is-an-example:role/teleport-redshift-serverless-node",
                "Service": "ec2.amazonaws.com"
            },
            "Action": "sts:AssumeRole"
        }
    ]
}

Remember to replace the example AWS account ID.

Create and apply a permission policy to allow access to Redshift Serverless. This policy can allow access to all instances:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "redshift-serverless:GetCredentials",
            "Resource": "*"
        }
    ]
}

Or you can restrict the Resource line to a specific Redshift Serverless workgroup:

{
...
      "Resource": "arn:aws:redshift-serverless:us-west-2:1234567890:workgroup/some-workgroup-id"
...
}

Step 2/4. Create a Teleport role for Redshift Serverless access

On your workstation logged in to your Teleport cluster with tsh, define a new role to provide access to Redshift Serverless. Our example file is redshift-role.yaml:

version: v5
kind: role
metadata:
  name: redshift-serverless-access
spec:
  allow:
    db_labels:
      '*': '*'
    db_names:
    - dev
    db_users:
    - 'teleport-redshift-serverless-access'
  • The value of db_users corresponds to the IAM role created in the previous step. You can provide either the role name or the full AWS ARN of the IAM role.
  • The value(s) for db_names will depend on your Redshift Serverless configuration, but dev is the default name applied by AWS. You can also provide * to grant access to all instances.

Save this file and apply it to your Teleport cluster:

tctl create -f redshift-role.yaml
role 'redshift-serverless-access' has been created

Assign the redshift-serverless-access role to your Teleport user by running the appropriate commands for your authentication provider:

  1. Retrieve your local user's roles as a comma-separated list:

    ROLES=$(tsh status -f json | jq -r '.active.roles | join(",")')
  2. Edit your local user to add the new role:

    tctl users update $(tsh status -f json | jq -r '.active.username') \ --set-roles "${ROLES?},redshift-serverless-access"
  3. Sign out of the Teleport cluster and sign in again to assume the new role.

  1. Retrieve your github authentication connector:

    tctl get github/github --with-secrets > github.yaml

    Note that the --with-secrets flag adds the value of spec.signing_key_pair.private_key to the github.yaml file. Because this key contains a sensitive value, you should remove the github.yaml file immediately after updating the resource.

  2. Edit github.yaml, adding redshift-serverless-access to the teams_to_roles section.

    The team you should map to this role depends on how you have designed your organization's role-based access controls (RBAC). However, the team must include your user account and should be the smallest team possible within your organization.

    Here is an example:

      teams_to_roles:
        - organization: octocats
          team: admins
          roles:
            - access
    +       - redshift-serverless-access
    
  3. Apply your changes:

    tctl create -f github.yaml
  4. Sign out of the Teleport cluster and sign in again to assume the new role.

  1. Retrieve your saml configuration resource:

    tctl get --with-secrets saml/mysaml > saml.yaml

    Note that the --with-secrets flag adds the value of spec.signing_key_pair.private_key to the saml.yaml file. Because this key contains a sensitive value, you should remove the saml.yaml file immediately after updating the resource.

  2. Edit saml.yaml, adding redshift-serverless-access to the attributes_to_roles section.

    The attribute you should map to this role depends on how you have designed your organization's role-based access controls (RBAC). However, the group must include your user account and should be the smallest group possible within your organization.

    Here is an example:

      attributes_to_roles:
        - name: "groups"
          value: "my-group"
          roles:
            - access
    +       - redshift-serverless-access
    
  3. Apply your changes:

    tctl create -f saml.yaml
  4. Sign out of the Teleport cluster and sign in again to assume the new role.

  1. Retrieve your oidc configuration resource:

    tctl get oidc/myoidc --with-secrets > oidc.yaml

    Note that the --with-secrets flag adds the value of spec.signing_key_pair.private_key to the oidc.yaml file. Because this key contains a sensitive value, you should remove the oidc.yaml file immediately after updating the resource.

  2. Edit oidc.yaml, adding redshift-serverless-access to the claims_to_roles section.

    The claim you should map to this role depends on how you have designed your organization's role-based access controls (RBAC). However, the group must include your user account and should be the smallest group possible within your organization.

    Here is an example:

      claims_to_roles:
        - name: "groups"
          value: "my-group"
          roles:
            - access
    +       - redshift-serverless-access
    
  3. Apply your changes:

    tctl create -f oidc.yaml
  4. Sign out of the Teleport cluster and sign in again to assume the new role.

Step 3/4. Install and start the Teleport Database Service

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

For users with a lot of infrastructure in AWS, or who might create or recreate many instances, consider alternative methods for joining new EC2 instances running Teleport:

Install Teleport on your Linux server:

  1. Assign edition to one of the following, depending on your Teleport edition:

    EditionValue
    Teleport Enterprise Cloudcloud
    Teleport Enterprise (Self-Hosted)enterprise
    Teleport Community Editionoss
  2. Get the version of Teleport to install. If you have automatic agent updates enabled in your cluster, query the latest Teleport version that is compatible with the updater:

    TELEPORT_DOMAIN=example.teleport.com
    TELEPORT_VERSION="$(curl https://$TELEPORT_DOMAIN/v1/webapi/automaticupgrades/channel/default/version | sed 's/v//')"

    Otherwise, get the version of your Teleport cluster:

    TELEPORT_DOMAIN=example.teleport.com
    TELEPORT_VERSION="$(curl https://$TELEPORT_DOMAIN/v1/webapi/ping | jq -r '.server_version')"
  3. Install Teleport on your Linux server:

    curl https://goteleport.com/static/install.sh | bash -s ${TELEPORT_VERSION} edition

    The installation script detects the package manager on your Linux server and uses it to install Teleport binaries. To customize your installation, learn about the Teleport package repositories in the installation guide.

On the same host, run the following command:

sudo teleport db configure create \ -o file \ --name="redshift-serverless" \ --proxy=example.teleport.sh:443 \ --protocol=postgres \ --uri=REDSHIFT_SERVERLESS_URI \ --token=/tmp/token

Replace example.teleport.sh:443 with the host and port of your Teleport Proxy Service. Replace REDSHIFT_SERVERLESS_URI with the domain name and port of your Redshift Serverless database.

Bootstrap access to Redshift Serverless

Grant the Database Service access to credentials that it can use to authenticate to AWS. If you are running the Database Service on an EC2 instance, you may use the EC2 Instance Metadata Service method. Otherwise, you must use environment variables:

Teleport will detect when it is running on an EC2 instance and use the Instance Metadata Service to fetch credentials.

The EC2 instance should be configured to use an EC2 instance profile. For more information, see: Using Instance Profiles.

Teleport's built-in AWS client reads credentials from the following environment variables:

  • AWS_ACCESS_KEY_ID
  • AWS_SECRET_ACCESS_KEY
  • AWS_DEFAULT_REGION

When you start the Database Service, the service reads environment variables from a file at the path /etc/default/teleport. Obtain these credentials from your organization. Ensure that /etc/default/teleport has the following content, replacing the values of each variable:

AWS_ACCESS_KEY_ID=00000000000000000000
AWS_SECRET_ACCESS_KEY=0000000000000000000000000000000000000000
AWS_DEFAULT_REGION=<YOUR_REGION>

Teleport's AWS client loads credentials from different sources in the following order:

  • Environment Variables
  • Shared credentials file
  • Shared configuration file (Teleport always enables shared configuration)
  • EC2 Instance Metadata (credentials only)

While you can provide AWS credentials via a shared credentials file or shared configuration file, you will need to run the Database Service with the AWS_PROFILE environment variable assigned to the name of your profile of choice.

If you have a specific use case that the instructions above do not account for, consult the documentation for the AWS SDK for Go for a detailed description of credential loading behavior.

Teleport can bootstrap IAM permissions for the Database Service based on its configuration using the teleport db configure bootstrap command. You can use this command in automatic or manual mode:

  • In automatic mode, Teleport will attempt to create appropriate IAM policies and attach them to the specified IAM identity (user or role). This requires IAM permissions to create and attach IAM policies.
  • In manual mode, Teleport will print required IAM policies. You can then create and attach them manually using the AWS management console.

Use this command to bootstrap the permissions automatically when your Teleport Database Service runs as an IAM user (for example, uses an AWS credentials file).

teleport db configure bootstrap -c /etc/teleport.yaml --attach-to-user teleport-redshift-serverless-access

Use this command to bootstrap the permissions automatically when your Teleport Database Service runs as an IAM role (for example, on an EC2 instance with an attached IAM role).

teleport db configure bootstrap -c /etc/teleport.yaml --attach-to-role teleport-redshift-serverless-node

Use this command to display required IAM policies which you will then create in your AWS console:

teleport db configure bootstrap -c /etc/teleport.yaml --manual --attach-to-user arn:aws:iam::123456789012:user/teleport-redshift-serverless-access

Use this command to display required IAM policies which you will then create in your AWS console:

teleport db configure bootstrap -c /etc/teleport.yaml --manual --attach-to-role arn:aws:iam::123456789012:role/teleport-redshift-serverless-node

When assume_role_arn is configured for databases or AWS matchers, teleport db configure bootstrap will determine permissions required for the bootstrap target AWS IAM identity using the following logic:

  • When the target does not match assume_role_arn in any database resource or AWS matcher in the configuration file, the target is assumed to be the Teleport Database Service's AWS IAM identity and permissions are bootstrapped for all the configured static databases and AWS matchers.
  • When an --attach-to-role target matches an assume_role_arn setting for static databases or AWS matchers in the configuration file, permissions will be bootstrapped only for those static databases or AWS matchers.

You will need to run the bootstrap command once with the Teleport Database Service's IAM identity as the policy attachment target, and once for each AWS IAM role that is used for assume_role_arn.

Start the 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

On the host where you will run the Teleport Database Service, create a systemd service configuration for Teleport, enable the Teleport service, and start Teleport:

sudo teleport install systemd -o /etc/systemd/system/teleport.service
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.

Step 4/4. Connect

Once the Database Service has started and joined the cluster, log in to see the registered databases. Replace --proxy with the address of your Teleport Proxy Service or cloud tenant:

tsh login --proxy=mytenant.teleport.sh --user=alice
tsh db ls
Name Description Labels----------- ------------------------------ --------my-redshift ...

To connect to the Redshift Serverless instance:

tsh db connect my-redshift --db-user=teleport-redshift-serverless-access --db-name=dev
psql (15.1, server 8.0.2)WARNING: psql major version 15, server major version 8.0. Some psql features might not work.SSL connection (protocol: TLSv1.3, cipher: TLS_CHACHA20_POLY1305_SHA256, compression: off)Type "help" for help.
dev=>

To log out of the database and remove credentials:

tsh db logout my-redshift

Troubleshooting

User permission errors

The IAM role teleport-redshift-serverless-access will be automatically mapped as IAMR:teleport-redshift-serverless-access inside the Redshift Serverless database.

Users (database admins) can optionally set up this database user's permissions prior to logging in as this new IAM role to avoid or resolve user permission issues:

  1. Connect to the Redshift Serverless workgroup as the admin user, and execute:

    CREATE USER "IAMR:teleport-redshift-serverless-access" WITH PASSWORD DISABLE;
    
  2. Grant this user appropriate in-database permissions. For example:

    GRANT SELECT ON TABLE users  TO "IAMR:teleport-redshift-serverless-access";
    

Certificate error

If your tsh db connect error includes the following text, you likely have an RDS database created before July 28, 2020, which presents an X.509 certificate that is incompatible with Teleport:

x509: certificate relies on legacy Common Name field, use SANs instead

AWS provides instructions to rotate your SSL/TLS certificate.

No credential providers error

If you see the error NoCredentialProviders: no valid providers in chain in Database Service logs then Teleport is not detecting the required credentials to connect via AWS IAM permissions. Check whether the credentials or security role has been applied in the machine running the Teleport Database Service.

When running on EKS, this error may occur if the Teleport Database Service cannot access IMDSv2 when the PUT requests hop limit on the worker node instance is set to 1. You can use the following commands to check the hop limit:

aws ec2 describe-instances --instance-ids <node-instance-id> | grep HttpPutResponseHopLimit
"HttpPutResponseHopLimit": 1,

See IMDSv2 support for EKS and EKS best practices for more details.

Timeout errors

The Teleport Database Service needs connectivity to your database endpoints. That may require enabling inbound traffic on the database from the Database Service on the same VPC or routing rules from another VPC. Using the nc program you can verify connections to databases:

nc -zv postgres-instance-1.sadas.us-east-1.rds.amazonaws.com 5432

Connection to postgres-instance-1.sadas.us-east-1.rds.amazonaws.com (172.31.24.172) 5432 port [tcp/postgresql] succeeded!

Not authorized to perform sts:AssumeRole

The Database Service assumes an IAM role in one of following situations:

  • An IAM role is used as db_user when accessing AWS services that require IAM roles as database users, such as DynamoDB, Keyspaces, Opensearch, and Redshift Serverless.
  • The assume_role_arn field is specified for the database resources or dynamic resource matchers.

When both of the above conditions are true for a database connection, the Database Service performs a role chaining by assuming the IAM role specified assume_role_arn first then using that IAM role to assume the IAM role for db_user.

You may encounter the following error if the trust relationship is not configured properly between the IAM roles:

AccessDenied: User: arn:aws:sts::111111111111:assumed-role/database-service-role/i-* is not authorized to perform: sts:AssumeRole on resource: arn:aws:iam::111111111111:role/database-user-role

To allow IAM Role role1 to assume IAM Role role2, the following is generally required:

role1 or its AWS account should be set as Principal in role2's trust policy.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::aws-account-id:role/role1"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::aws-account-id:root"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::external-aws-account-id:role/role1"
      },
      "Action": "sts:AssumeRole",
      "Condition": {
        "StringEquals": {
          "sts:ExternalId": "example-external-id"
        }
      }
    }
  ]
}

role1 requires sts:AssumeRole permissions, for example:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": "sts:AssumeRole",
            "Effect": "Allow",
            "Resource": "arn:aws:iam::aws-account-id:role/role2"
        }
    ]
}

Note that this policy can be omitted when role1 and role2 are in the same AWS account and role1's full ARN is configured as Principal in role2's trust policy.

role1 also requires sts:AssumeRole permissions in its boundary policy, for example:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": "sts:AssumeRole",
            "Effect": "Allow",
            "Resource": "*"
        }
    ]
}

Note that this is only required when a boundary policy is attached to role1.

You can test the trust relationship by running this AWS CLI command as role1:

aws sts assume-role --role-arn arn:aws:iam::111111111111:role/role2 --role-session-name test-trust-relationship

Learn more on how to use trust policies with IAM roles.

Unable to cancel a query

If you use a PostgreSQL cli client like psql, and you try to cancel a query with ctrl+c, but it doesn't cancel the query, then you need to connect using a tsh local proxy instead. When psql cancels a query, it establishes a new connection without TLS certificates, however Teleport requires TLS certificates not only for authentication, but also to route database connections.

If you enable TLS Routing in Teleport then tsh db connect will automatically start a local proxy for every connection. Alternatively, you can connect via Teleport Connect which also uses a local proxy. Otherwise, you need to start a tsh local proxy manually using tsh proxy db and connect via the local proxy.

If you have already started a long-running query in a psql session that you cannot cancel with ctrl+c, you can start a new client session to cancel that query manually:

First, find the query's process identifier (PID):

SELECT session_id AS pid, database_name,start_time,trim(query_text) AS query FROM SYS_QUERY_HISTORY WHERE status = 'running';

Next, gracefully cancel the query using its PID. This will send a SIGINT signal to the postgres backend process for that query:

SELECT pg_cancel_backend(<PID>);

You should always try to gracefully terminate a query first, but if graceful cancellation is taking too long, then you can forcefully terminate the query instead. This will send a SIGTERM signal to the postgres backend process for that query:

SELECT pg_terminate_backend(<PID>);

See the PostgreSQL documentation on admin functions for more information about the pg_cancel_backend and pg_terminate_backend functions.

Next steps