Chapter 5. Tutorial: Using AWS WAF and AWS ALBs to protect ROSA workloads

Create a new project to deploy the AWS Load Balancer Operator into by running the following command:

$ oc new-project aws-load-balancer-operator

Create an AWS IAM policy for the AWS Load Balancer Controller if one does not already exist by running the following command:

$ POLICY_ARN=$(aws iam list-policies --query \
     "Policies[?PolicyName=='aws-load-balancer-operator-policy'].{ARN:Arn}" \
     --output text)

$ if [[ -z "${POLICY_ARN}" ]]; then
    wget -O "${SCRATCH}/load-balancer-operator-policy.json" \
       https://raw.githubusercontent.com/kubernetes-sigs/aws-load-balancer-controller/main/docs/install/iam_policy.json
     POLICY_ARN=$(aws --region "$REGION" --query Policy.Arn \
     --output text iam create-policy \
     --policy-name aws-load-balancer-operator-policy \
     --policy-document "file://${SCRATCH}/load-balancer-operator-policy.json")
fi

Create an AWS IAM trust policy for AWS Load Balancer Operator:

$ cat <<EOF > "${SCRATCH}/trust-policy.json"
{
 "Version": "2012-10-17",
 "Statement": [
 {
 "Effect": "Allow",
 "Condition": {
   "StringEquals" : {
     "${OIDC_ENDPOINT}:sub": ["system:serviceaccount:aws-load-balancer-operator:aws-load-balancer-operator-controller-manager", "system:serviceaccount:aws-load-balancer-operator:aws-load-balancer-controller-cluster"]
   }
 },
 "Principal": {
   "Federated": "arn:aws:iam::$AWS_ACCOUNT_ID:oidc-provider/${OIDC_ENDPOINT}"
 },
 "Action": "sts:AssumeRoleWithWebIdentity"
 }
 ]
}
EOF

Create an AWS IAM role for the AWS Load Balancer Operator:

$ ROLE_ARN=$(aws iam create-role --role-name "${CLUSTER}-alb-operator" \
   --assume-role-policy-document "file://${SCRATCH}/trust-policy.json" \
   --query Role.Arn --output text)

Attach the AWS Load Balancer Operator policy to the IAM role we created previously by running the following command:

$ aws iam attach-role-policy --role-name "${CLUSTER}-alb-operator" \
     --policy-arn ${POLICY_ARN}

Create a secret for the AWS Load Balancer Operator to assume our newly created AWS IAM role:

$ cat << EOF | oc apply -f -
apiVersion: v1
kind: Secret
metadata:
  name: aws-load-balancer-operator
  namespace: aws-load-balancer-operator
stringData:
  credentials: |
    [default]
    role_arn = ${ROLE_ARN}
    web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
EOF

Install the AWS Load Balancer Operator:

$ cat << EOF | oc apply -f -
apiVersion: operators.coreos.com/v1
kind: OperatorGroup
metadata:
  name: aws-load-balancer-operator
  namespace: aws-load-balancer-operator
spec:
  upgradeStrategy: Default
---
apiVersion: operators.coreos.com/v1alpha1
kind: Subscription
metadata:
  name: aws-load-balancer-operator
  namespace: aws-load-balancer-operator
spec:
  channel: stable-v1.0
  installPlanApproval: Automatic
  name: aws-load-balancer-operator
  source: redhat-operators
  sourceNamespace: openshift-marketplace
  startingCSV: aws-load-balancer-operator.v1.0.0
EOF

Deploy an instance of the AWS Load Balancer Controller using the operator:

$ cat << EOF | oc apply -f -
apiVersion: networking.olm.openshift.io/v1
kind: AWSLoadBalancerController
metadata:
  name: cluster
spec:
  credentials:
    name: aws-load-balancer-operator
  enabledAddons:
    - AWSWAFv2
EOF

Check the that the operator and controller pods are both running:

$ oc -n aws-load-balancer-operator get pods

You should see the following, if not wait a moment and retry:

NAME                                                             READY   STATUS    RESTARTS   AGE
aws-load-balancer-controller-cluster-6ddf658785-pdp5d            1/1     Running   0          99s
aws-load-balancer-operator-controller-manager-577d9ffcb9-w6zqn   2/2     Running   0          2m4s

Create a new project for our sample application:

$ oc new-project hello-world

Deploy a hello world application:

$ oc new-app -n hello-world --image=docker.io/openshift/hello-openshift

Convert the pre-created service resource to a NodePort service type:

$ oc -n hello-world patch service hello-openshift -p '{"spec":{"type":"NodePort"}}'

Deploy an AWS ALB using the AWS Load Balancer Operator:

$ cat << EOF | oc apply -f -
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: hello-openshift-alb
  namespace: hello-world
  annotations:
    alb.ingress.kubernetes.io/scheme: internet-facing
spec:
  ingressClassName: alb
  rules:
    - http:
        paths:
          - path: /
            pathType: Exact
            backend:
              service:
                name: hello-openshift
                port:
                  number: 8080
EOF

Curl the AWS ALB Ingress endpoint to verify the hello world application is accessible:

$ INGRESS=$(oc -n hello-world get ingress hello-openshift-alb -o jsonpath='{.status.loadBalancer.ingress[0].hostname}')
$ curl "http://${INGRESS}"

Hello OpenShift!