Vault Secrets Operator

The Vault Secrets Operator (VSO) allows Pods to consume Vault secrets natively from Kubernetes Secrets.

Overview

The Vault Secrets Operator operates by watching for changes to its supported set of Custom Resource Definitions (CRD). Each CRD provides the specification required to allow the Operator to synchronize a Vault Secrets to a Kubernetes Secret. The Operator writes the source Vault secret data directly to the destination Kubernetes Secret, ensuring that any changes made to the source are replicated to the destination over its lifetime. In this way, an application only needs to have access to the destination secret in order to make use of the secret data contained within.

See the developer docs for more info here

Features

The following features are supported by the Vault Secrets Operator:

All Vault secret engines supported.
TLS/mTLS communications with Vault.
Authentication using the requesting Pod's ServiceAccount via the Kubernetes Auth Method
Syncing Vault Secrets to Kubernetes Secrets.
Secret rotation for Deployment, ReplicaSet, StatefulSet Kubernetes resource types.
Prometheus' instrumentation for monitoring the Operator
Supported installation methods: Helm, Kustomize

Samples

Setup kubernetes and deploy the samples:

# Start a KinD cluster
make setup-kind

# Deploy Vault
make setup-integration-test

# Configure Vault
./config/samples/setup.sh

# Build and deploy the operator
make build docker-build deploy-kind

# Deploy the sample K8s resources
kubectl apply -k config/samples

Inspect the resulting secrets:

kubectl get secrets -n tenant-1 secret1 -o yaml

kubectl get secrets -n tenant-1 pki1 -o yaml

kubectl get secrets -n tenant-2 secret1 -o yaml

Delete the samples:

kubectl delete -k config/samples

Ingress TLS with VaultPKISecret

The file config/samples/secrets_v1beta1_vaultpkisecret_tls.yaml contains an example of using VaultPKISecret to populate a TLS secret for use with an Ingress. This sample takes a little more setup to test it out (derived from the kind docs).

The TLS example is part of the samples, so setup kind, configure Vault, and deploy the operator as described above.

Then deploy the nginx ingress controller:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/main/deploy/static/provider/kind/deploy.yaml

kubectl wait --namespace ingress-nginx \
  --for=condition=ready pod \
  --selector=app.kubernetes.io/component=controller \
  --timeout=90s

Check the deployed app with something like curl, it should return the tls-app hostname, and the certificate should have a ~1.5m TTL:

$ curl -k https://localhost:38443/tls-app/hostname
tls-app

$ curl -kvI https://localhost:38443/tls-app/hostname
...
* Server certificate:
*  subject: CN=localhost
*  start date: Mar 17 05:53:28 2023 GMT
*  expire date: Mar 17 05:54:58 2023 GMT
*  issuer: CN=example.com
...

Watch the nginx controller logs to see the TLS secret being rotated:

kubectl logs -f -n ingress-nginx -l app.kubernetes.io/instance=ingress-nginx

Tests

Unit Tests

make test

Integration Tests

# Start a KinD cluster
make setup-kind

# Build the operator binary, image, and deploy to the KinD cluster
make ci-build ci-docker-build ci-deploy-kind ci-deploy

# Run the integration tests (includes Vault deployment)
make integration-test

Integration Tests in EKS

# Create an EKS cluster and a ECR repository
make -f aws.mk create-eks

# Build the operator image and run the integration tests (includes Vault Community deployment)
make -f aws.mk build-push integration-test-eks

# Run the integration tests (includes Vault ent deployment, have the Vault license as environment variable)
make -f aws.mk build-push integration-test-eks VAULT_ENTERPRISE=true ENT_TESTS=true

AWS auth test with static credentials

# Set SKIP_AWS_STATIC_CREDS_TEST=false and set the credentials for the static creds user via the environment variables TEST_AWS_ACCESS_KEY_ID,
# TEST_AWS_SECRET_ACCESS_KEY, TEST_AWS_STATIC_CREDS_ROLE (and TEST_AWS_SESSION_TOKEN if applicable) for a user in AWS.
# Note: these credentials will be set in a Kubernetes secret.
export TEST_AWS_ACCESS_KEY_ID="..."
export TEST_AWS_SECRET_ACCESS_KEY="..."
export TEST_AWS_SESSION_TOKEN="..."
export AWS_STATIC_CREDS_ROLE="arn:aws:iam::..."
make -f aws.mk integration-test-eks TESTARGS="-run TestVaultAuth" SKIP_AWS_STATIC_CREDS_TEST=false

Integration Tests in GKE

# Export the Google Cloud project id
export GCP_PROJECT="<project_id>"

# Create an GKE cluster and a GAR repository
make -f gcp.mk create-gke

# Build & operator image & run the integration tests (includes Vault Community deployment)
make -f gcp.mk build-push integration-test-gke

# Run the integration tests (includes Vault ent deployment, have the Vault license as environment variable)
make -f gcp.mk build-push integration-test-gke VAULT_ENTERPRISE=true ENT_TESTS=true

Integration Tests in AKS

# Export the Azure credentials
az config set core.allow_broker=true && az account clear && az login
az account set --subscription "<subscription_id>"
az ad sp create-for-rbac --name "vault-secrets-operator" --role "Owner" --scopes /subscriptions/<subscription_id> --output json
export AZURE_APPID="<app_id>"
export AZURE_PASSWORD="<password>"
export AZURE_TENANT="<tenant_id>"

# Create an AKS cluster and a ACR repository
make -f azure.mk create-aks

# Build  the operator image and run the integration tests (includes Vault Community deployment)
make -f azure.mk build-push integration-test-aks

# Run the integration tests (includes Vault ent deployment, have the Vault license as environment variable)
make -f azure.mk build-push integration-test-aks VAULT_ENTERPRISE=true ENT_TESTS=true

hashicorp/vault-secrets-operator