AWS Parameter Store
Parameter Store
A ParameterStore
points to AWS SSM Parameter Store in a certain account within a
defined region. You should define Roles that define fine-grained access to
individual secrets and pass them to ESO using spec.provider.aws.role
. This
way users of the SecretStore
can only access the secrets necessary.
apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
name: parameterstore
spec:
provider:
aws:
service: ParameterStore
# define a specific role to limit access
# to certain secrets
role: arn:aws:iam::123456789012:role/external-secrets
region: eu-central-1
auth:
secretRef:
accessKeyIDSecretRef:
name: awssm-secret
key: access-key
secretAccessKeySecretRef:
name: awssm-secret
key: secret-access-key
NOTE: In case of a ClusterSecretStore
, Be sure to provide namespace
in accessKeyIDSecretRef
and secretAccessKeySecretRef
with the namespaces where the secrets reside.
API Pricing & Throttling
The SSM Parameter Store API is charged by throughput and is available in different tiers, see pricing. Please estimate your costs before using ESO. Cost depends on the RefreshInterval of your ExternalSecrets.
IAM Policy
Create a IAM Policy to pin down access to secrets matching dev-*
, for further information see AWS Documentation:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"ssm:GetParameterWithContext",
"ssm:ListTagsForResourceWithContext",
"ssm:DescribeParametersWithContext",
],
"Resource": "arn:aws:ssm:us-east-2:1234567889911:parameter/dev-*"
}
]
}
JSON Secret Values
You can store JSON objects in a parameter. You can access nested values or arrays using gjson syntax:
Consider the following JSON object that is stored in the Parameter Store key friendslist
:
{
"name": {"first": "Tom", "last": "Anderson"},
"friends": [
{"first": "Dale", "last": "Murphy"},
{"first": "Roger", "last": "Craig"},
{"first": "Jane", "last": "Murphy"}
]
}
This is an example on how you would look up nested keys in the above json object:
apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
name: extract-data
spec:
# [omitted for brevity]
data:
- secretKey: my_name
remoteRef:
key: friendslist
property: name.first # Tom
- secretKey: first_friend
remoteRef:
key: friendslist
property: friends.1.first # Roger
Parameter Versions
ParameterStore creates a new version of a parameter every time it is updated with a new value. The parameter can be referenced via the version
property
SetSecret
The SetSecret method for the Parameter Store allows the user to set the value stored within the Kubernetes cluster to the remote AWS Parameter Store.
Creating a Push Secret
apiVersion: external-secrets.io/v1alpha1
kind: PushSecret
metadata:
name: pushsecret-example # Customisable
namespace: default # Same of the SecretStores
spec:
refreshInterval: 10s # Refresh interval for which push secret will reconcile
secretStoreRefs: # A list of secret stores to push secrets to
- name: aws-parameterstore
kind: SecretStore
selector:
secret:
name: pokedex-credentials # Source Kubernetes secret to be pushed
data:
- match:
secretKey: best-pokemon # Source Kubernetes secret key to be pushed
remoteRefs:
- remoteKey: my-first-parameter # Remote reference (where the secret is going to be pushed)
Check successful secret sync
To be able to check that the secret has been succesfully synced you can run the following command:
kubectl get pushsecret pushsecret-example
If the secret has synced successfully it will show the status as "Synced".
Test new secret using AWS CLI
To View your parameter on AWS Parameter Store using the AWS CLI, install and login to the AWS CLI using the following guide: AWS CLI.
Run the following commands to get your synchronized parameter from AWS Parameter Store:
aws ssm get-parameter --name=my-first-parameter --region=us-east-1
You should see something similar to the following output:
{
"Parameter": {
"Name": "my-first-parameter",
"Type": "String",
"Value": "charmander",
"Version": 4,
"LastModifiedDate": "2022-09-15T13:04:31.098000-03:00",
"ARN": "arn:aws:ssm:us-east-1:1234567890123:parameter/my-first-parameter",
"DataType": "text"
}
}
AWS Authentication
Controller's Pod Identity
Note: If you are using Parameter Store replace service: SecretsManager
with service: ParameterStore
in all examples below.
This is basicially a zero-configuration authentication method that inherits the credentials from the runtime environment using the aws sdk default credential chain.
You can attach a role to the pod using IRSA, kiam or kube2iam. When no other authentication method is configured in the Kind=Secretstore
this role is used to make all API calls against AWS Secrets Manager or SSM Parameter Store.
Based on the Pod's identity you can do a sts:assumeRole
before fetching the secrets to limit access to certain keys in your provider. This is optional.
apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
name: team-b-store
spec:
provider:
aws:
service: SecretsManager
region: eu-central-1
# optional: do a sts:assumeRole before fetching secrets
role: team-b
Access Key ID & Secret Access Key
You can store Access Key ID & Secret Access Key in a Kind=Secret
and reference it from a SecretStore.
apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
name: team-b-store
spec:
provider:
aws:
service: SecretsManager
region: eu-central-1
# optional: assume role before fetching secrets
role: team-b
auth:
secretRef:
accessKeyIDSecretRef:
name: awssm-secret
key: access-key
secretAccessKeySecretRef:
name: awssm-secret
key: secret-access-key
NOTE: In case of a ClusterSecretStore
, Be sure to provide namespace
in accessKeyIDSecretRef
, secretAccessKeySecretRef
with the namespaces where the secrets reside.
EKS Service Account credentials
This feature lets you use short-lived service account tokens to authenticate with AWS. You must have Service Account Volume Projection enabled - it is by default on EKS. See EKS guide on how to set up IAM roles for service accounts.
The big advantage of this approach is that ESO runs without any credentials.
apiVersion: v1
kind: ServiceAccount
metadata:
annotations:
eks.amazonaws.com/role-arn: arn:aws:iam::123456789012:role/team-a
name: my-serviceaccount
namespace: default
Reference the service account from above in the Secret Store:
apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
name: secretstore-sample
spec:
provider:
aws:
service: SecretsManager
region: eu-central-1
auth:
jwt:
serviceAccountRef:
name: my-serviceaccount
NOTE: In case of a ClusterSecretStore
, Be sure to provide namespace
for serviceAccountRef
with the namespace where the service account resides.
Custom Endpoints
You can define custom AWS endpoints if you want to use regional, vpc or custom endpoints. See List of endpoints for Secrets Manager, Secure Systems Manager and Security Token Service.
Use the following environment variables to point the controller to your custom endpoints. Note: All resources managed by this controller are affected.
ENV VAR | DESCRIPTION |
---|---|
AWS_SECRETSMANAGER_ENDPOINT | Endpoint for the Secrets Manager Service. The controller uses this endpoint to fetch secrets from AWS Secrets Manager. |
AWS_SSM_ENDPOINT | Endpoint for the AWS Secure Systems Manager. The controller uses this endpoint to fetch secrets from SSM Parameter Store. |
AWS_STS_ENDPOINT | Endpoint for the Security Token Service. The controller uses this endpoint when creating a session and when doing assumeRole or assumeRoleWithWebIdentity calls. |