Add hardened cluster test

scripts/hardened/cluster-level-pss.yaml

+apiVersion: apiserver.config.k8s.io/v1
+kind: AdmissionConfiguration
+plugins:
+- name: PodSecurity
+  configuration:
+    apiVersion: pod-security.admission.config.k8s.io/v1beta1
+    kind: PodSecurityConfiguration
+    defaults:
+      enforce: "privileged"
+      enforce-version: "latest"
+      audit: "baseline"
+      audit-version: "latest"
+      warn: "baseline"
+      warn-version: "latest"
+    exemptions:
+      usernames: []
+      runtimeClasses: []
+      namespaces: [kube-system]

scripts/hardened/hardened-k3s-ingress.yaml

+apiVersion: apps/v1
+kind: DaemonSet
+metadata:
+  name: example
+  namespace: default
+  labels:
+    app.kubernetes.io: example
+spec:
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: example
+  template:
+    metadata:
+      labels:
+        app.kubernetes.io/name: example
+    spec:
+      automountServiceAccountToken: false
+      securityContext:
+        runAsUser: 405
+        runAsGroup: 100
+      containers:
+      - name: socat
+        image: docker.io/alpine/socat:1.7.4.3-r1
+        args:
+        - "TCP-LISTEN:8080,reuseaddr,fork"
+        - "EXEC:echo -e 'HTTP/1.1 200 OK\r\nConnection: close\r\n\r\n$(NODE_IP) $(POD_NAMESPACE)/$(POD_NAME)\r\n'"
+        ports:
+        - containerPort: 8080
+          name: http
+        env:
+        - name: NODE_IP
+          valueFrom:
+            fieldRef:
+              fieldPath: status.hostIP
+        - name: POD_NAMESPACE
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.namespace
+        - name: POD_NAME
+          valueFrom:
+            fieldRef:
+              fieldPath: metadata.name
+        readinessProbe:
+          initialDelaySeconds: 2
+          periodSeconds: 10
+          httpGet:
+            path: /
+            port: 8080
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: example
+  namespace: default
+spec:
+  type: NodePort
+  selector:
+    app.kubernetes.io/name: example
+  ports:
+  - name: http
+    protocol: TCP
+    port: 80
+    nodePort: 30096
+    targetPort: http
+---
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: example
+spec:
+  rules:
+  - host: "example.com"
+    http:
+      paths:
+      - pathType: Prefix
+        path: "/"
+        backend:
+          service:
+            name: example
+            port:
+              name: http
+---
+# Allow access to example backend from traefik ingress
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  name: ingress-to-backend-example
+  namespace: default
+spec:
+  podSelector:
+    matchLabels:
+      app.kubernetes.io/name: example
+  ingress:
+  - ports:
+    - port: 8080
+      protocol: TCP
+  - from:
+    - namespaceSelector:
+        matchLabels:
+          kubernetes.io/metadata.name: kube-system
+      podSelector:
+        matchLabels:
+          app.kubernetes.io/name: traefik
+  policyTypes:
+  - Ingress
+---
+# Allow access to example backend from outside the cluster via nodeport service
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  name: nodeport-to-backend-example
+  namespace: default
+spec:
+  podSelector:
+    matchLabels:
+      app.kubernetes.io/name: example
+  ingress:
+  - ports:
+    - port: 8080
+      protocol: TCP
+  - from:
+    - ipBlock:
+        cidr: 0.0.0.0/0
+        except:
+          - 10.42.0.0/16
+          - 10.43.0.0/16
+  policyTypes:
+  - Ingress

scripts/hardened/hardened-k3s-netpol.yaml

+---
+# Allow all traffic within the kube-system namespace; block all other access
+kind: NetworkPolicy
+apiVersion: networking.k8s.io/v1
+metadata:
+  name: intra-namespace
+  namespace: kube-system
+spec:
+  podSelector: {}
+  ingress:
+    - from:
+      - namespaceSelector:
+          matchLabels:
+            name: kube-system
+  policyTypes:
+  - Ingress
+---
+# Allow all traffic within the default namespace; block all other access
+kind: NetworkPolicy
+apiVersion: networking.k8s.io/v1
+metadata:
+  name: intra-namespace
+  namespace: default
+spec:
+  podSelector: {}
+  ingress:
+    - from:
+      - namespaceSelector:
+          matchLabels:
+            name: default
+  policyTypes:
+  - Ingress
+---
+# Allow traffic within the kube-public namespace; block all other access
+kind: NetworkPolicy
+apiVersion: networking.k8s.io/v1
+metadata:
+  name: intra-namespace
+  namespace: kube-public
+spec:
+  podSelector: {}
+  ingress:
+    - from:
+      - namespaceSelector:
+          matchLabels:
+            name: kube-public
+  policyTypes:
+  - Ingress
+---
+# Allow all access to metrics-server
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  name: allow-all-metrics-server
+  namespace: kube-system
+spec:
+  podSelector:
+    matchLabels:
+      k8s-app: metrics-server
+  ingress:
+  - {}
+  policyTypes:
+  - Ingress
+---
+# Allow all access to coredns DNS ports
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  name: default-network-dns-policy
+  namespace: kube-system
+spec:
+  ingress:
+  - ports:
+    - port: 53
+      protocol: TCP
+    - port: 53
+      protocol: UDP
+  podSelector:
+    matchLabels:
+      k8s-app: kube-dns
+  policyTypes:
+  - Ingress
+---
+# Allow all access to the the servicelb traefik HTTP/HTTPS ports
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  name: allow-all-svclb-traefik
+  namespace: kube-system
+spec:
+  podSelector:
+    matchLabels:
+      svccontroller.k3s.cattle.io/svcname: traefik
+  ingress:
+  - ports:
+    - port: 80
+      protocol: TCP
+    - port: 443
+      protocol: TCP
+  policyTypes:
+  - Ingress
+---
+# Allow all access to traefik HTTP/HTTPS ports
+apiVersion: networking.k8s.io/v1
+kind: NetworkPolicy
+metadata:
+  name: allow-all-traefik
+  namespace: kube-system
+spec:
+  podSelector:
+    matchLabels:
+      app.kubernetes.io/name: traefik
+  ingress:
+  - ports:
+    - port: 8000
+      protocol: TCP
+    - port: 8443
+      protocol: TCP
+  policyTypes:
+  - Ingress

scripts/test-run-hardened

+#!/bin/bash
+
+all_services=(
+    coredns
+    local-path-provisioner
+    metrics-server
+    traefik
+)
+
+export NUM_SERVERS=1
+export NUM_AGENTS=1
+export WAIT_SERVICES="${all_services[@]}"
+export AGENT_ARGS="--selinux=true \
+--protect-kernel-defaults=true \
+--kubelet-arg=streaming-connection-idle-timeout=5m \
+--kubelet-arg=make-iptables-util-chains=true"
+export SERVER_ARGS="--selinux=true \
+--protect-kernel-defaults=true \
+--kubelet-arg=streaming-connection-idle-timeout=5m \
+--kubelet-arg=make-iptables-util-chains=true \
+--secrets-encryption=true \
+--kube-apiserver-arg=audit-log-path=/tmp/audit-log \
+--kube-apiserver-arg=audit-log-maxage=30 \
+--kube-apiserver-arg=audit-log-maxbackup=10 \
+--kube-apiserver-arg=audit-log-maxsize=100 \
+--kube-apiserver-arg=request-timeout=300s \
+--kube-apiserver-arg=service-account-lookup=true \
+--kube-apiserver-arg=enable-admission-plugins=NodeRestriction,NamespaceLifecycle,ServiceAccount \
+--kube-apiserver-arg=admission-control-config-file=/opt/rancher/k3s/cluster-level-pss.yaml \
+--kube-controller-manager-arg=terminated-pod-gc-threshold=10 \
+--kube-controller-manager-arg=use-service-account-credentials=true"
+
+# -- This test runs in docker mounting the docker socket,
+# -- so we can't directly mount files into the test containers. Instead we have to
+# -- run a dummy container with a volume, copy files into that volume, and then
+# -- share it with the other containers that need the file.
+cluster-pre-hook() {
+    mkdir -p $TEST_DIR/pause/0/metadata
+    local testID=$(basename $TEST_DIR)
+    local name=$(echo "k3s-pause-0-${testID,,}" | tee $TEST_DIR/pause/0/metadata/name)
+    export SERVER_DOCKER_ARGS="--mount type=volume,src=$name,dst=/opt/rancher/k3s"
+
+    docker run \
+        -d --name $name \
+        --hostname $name \
+        ${SERVER_DOCKER_ARGS} \
+        rancher/mirrored-pause:3.6 \
+        >/dev/null
+
+    docker cp scripts/hardened/cluster-level-pss.yaml $name:/opt/rancher/k3s/cluster-level-pss.yaml
+}
+export -f cluster-pre-hook
+
+# -- deploy and wait for a daemonset to run on all nodes, then wait a couple more
+# -- seconds for traefik to see the service endpoints before testing.
+start-test() {
+    find ./scripts/hardened/ -name 'hardened-k3s-*.yaml' -printf '-f\0%p\0' | xargs -tr0 kubectl create
+    kubectl rollout status daemonset/example --watch --timeout=5m
+    sleep 15
+    verify-ingress
+    verify-nodeport
+}
+export -f start-test
+
+test-cleanup-hook(){
+    local testID=$(basename $TEST_DIR)
+    docker volume ls -q | grep -F ${testID,,} | xargs -r docker volume rm
+}
+export -f test-cleanup-hook
+
+# -- confirm we can make a request through the ingress
+verify-ingress() {
+    local ips=$(cat $TEST_DIR/{servers,agents}/*/metadata/ip)
+    local schemes="http https"
+    for ip in $ips; do
+      for scheme in $schemes; do
+        curl -vksf -H 'Host: example.com' ${scheme}://${ip}/
+      done
+    done
+}
+export -f verify-ingress
+
+# -- confirm we can make a request through the nodeport service
+verify-nodeport() {
+    local ips=$(cat $TEST_DIR/{servers,agents}/*/metadata/ip)
+    local ports=$(kubectl get service/example -o 'jsonpath={.spec.ports[*].nodePort}')
+    for ip in $ips; do
+        for port in $ports; do
+            curl -vksf -H 'Host: example.com' http://${ip}:${port}
+        done
+    done
+}
+export -f verify-nodeport
+
+# --- create a basic cluster and check for functionality
+LABEL=HARDENED run-test
+
+cleanup-test-env