AWS Secrets Manager

AWS Secrets Manager can be configured in multiple ways.

To access secrets stored in the AWS Secrets Manager, Kong Gateway needs to be configured with an IAM Role that has sufficient permissions to read the required secret values.

Kong Gateway can automatically fetch IAM role credentials based on your AWS environment, observing the following precedence order:

• Fetch from credentials defined in environment variables AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.
• Fetch from profile and credential file, defined by AWS_PROFILE and AWS_SHARED_CREDENTIALS_FILE.
• Fetch from an ECS container credential provider.
• Fetch from an EKS IAM roles for service account.
• Fetch from EC2 IMDS metadata. Both v1 and v2 are supported

Kong Gateway also supports role assuming which allows you to use a different IAM role to fetch secrets from AWS Secrets Manager. This is a common practice in permission division and governance and cross-AWS account management.

You can customize the vault object by configuring a vaults entity in Kong Gateway.

AWS Secrets Manager configuration

To configure the vault backend with AWS Secrets Manager, you need to configure Kong Gateway to have the required IAM roles to access any relevant secrets.

For example, to use the secrets management with AWS environment variable credentials, configure the following environment variables on your Kong Gateway data plane:

export AWS_ACCESS_KEY_ID=<access_key_id>
export AWS_SECRET_ACCESS_KEY=<secrets_access_key>
export AWS_SESSION_TOKEN=<token>
export AWS_REGION=<aws-region>

The region used by default with references can also be specified with the following environment variable on your control plane:

export KONG_VAULT_AWS_REGION=<aws-region>

Additionally, if you want to use assume_role, make sure you have the following environment variables on your Kong Gateway data plane:

export KONG_VAULT_AWS_ASSUME_ROLE_ARN=<aws_iam_role_arn>
export KONG_VAULT_AWS_ROLE_SESSION_NAME=<aws_assume_role_session_name>

The vault backend configuration field can also be configured in the kong.conf file. See Gateway Enterprise configuration reference.

Note: When using AWS Vault as a backend, make sure you have configured system as part of the lua_ssl_trusted_certificate configuration directive so that the SSL certificates used by the official AWS API can be trusted by Kong.

Examples

For example, an AWS Secrets Manager secret with the name secret-name may have multiple key=value pairs:

{
  "foo": "bar",
  "snip": "snap"
}

Access these secrets from secret-name like this:

{vault://aws/secret-name/foo}
{vault://aws/secret-name/snip}

If you have an AWS Secrets Manager secret with multiple versions, you can access the current version or any previous version of the secret by specifying a version in the reference.

In the following example, AWSCURRENT refers to the latest secret version and AWSPREVIOUS refers to an older version:

# For AWSCURRENT, not specifying version
{vault://aws/secret-name/foo}

# For AWSCURRENT, specifying version == 1
{vault://aws/secret-name/foo#1}

# For AWSPREVIOUS, specifying version == 2
{vault://aws/secret-name/foo#2}

Note: The slash symbol (/) is a valid character for the secret name in AWS SecretsManager. If you want to reference a secret name that starts with a slash or has two consecutive slashes, transform one of the slashes in the name into URL-encoded format. For example:

• A secret named /secret/key should be referenced as {vault://aws/%2Fsecret/key}
• A secret named secret/path//aaa/key should be referenced as {vault://aws/secret/path/%2Faaa/key}

Since Kong Gateway tries to resolve the secret reference as a valid URL, using a slash instead of a URL-encoded slash will result in unexpected secret name fetching.

Configuration via vaults entity

The vault entity can only be used once the database is initialized. Secrets for values that are used before the database is initialized can’t make use of the vaults entity.

curl -i -X PUT http://localhost:8001/vaults/aws-sm-vault  \
  --data name=aws \
  --data description="Storing secrets in AWS Secrets Manager" \
  --data config.region="us-east-1"

{
    "config": {
        "region": "us-east-1"
    },
    "created_at": 1644942689,
    "description": "Storing secrets in AWS Secrets Manager",
    "id": "2911e119-ee1f-42af-a114-67061c3831e5",
    "name": "aws",
    "prefix": "aws-sm-vault",
    "tags": null,
    "updated_at": 1644942689
}

_format_version: "3.0"
vaults:
- config:
    region: us-east-1
  description: Storing secrets in AWS Secrets Manager
  name: aws
  prefix: aws-sm-vault

With the vault entity in place, you can now reference the secrets. This allows you to drop the AWS_REGION environment variable.

{vault://aws-sm-vault/secret-name/foo}
{vault://aws-sm-vault/secret-name/snip}

Secrets in different regions

You can create multiple entities, which lets you have secrets in different regions:

curl -X PUT http://localhost:8001/vaults/aws-eu-central-vault -d name=aws -d config.region="eu-central-1"

curl -X PUT http://localhost:8001/vaults/aws-us-west-vault -d name=aws -d config.region="us-west-1"

This lets you source secrets from different regions:

{vault://aws-eu-central-vault/secret-name/foo}
{vault://aws-us-west-vault/secret-name/snip}

Vault configuration options

Use the following configuration options to configure the vaults entity through any of the supported tools:

• Admin API
• Declarative configuration
• Kong Manager
• Konnect

Configuration options for an AWS Secrets Manager vault in Kong Gateway:

Common options: