Automatically Generate and Use Gossip Encryption Key

CHANGELOG.md

@@ -4,6 +4,7 @@ IMPROVEMENTS:
 * Control Plane
   * Upgrade Docker image Alpine version from 3.13 to 3.14. [[GH-737](https://github.com/hashicorp/consul-k8s/pull/737)]
 * Helm Chart
+  * Add automatic generation of gossip encryption with `global.gossipEncryption.autoGenerate=true` [[GH-738](https://github.com/hashicorp/consul-k8s/pull/738)]
   * Enable adding extra containers to server and client Pods.  [[GH-749](https://github.com/hashicorp/consul-k8s/pull/749)]
 
 ## 0.34.1 (September 17, 2021)

charts/consul/templates/client-daemonset.yaml

@@ -168,12 +168,17 @@ spec:
                   fieldPath: status.podIP
             - name: CONSUL_DISABLE_PERM_MGMT
               value: "true"
-            {{- if (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
+            {{- if (or .Values.global.gossipEncryption.autoGenerate (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey)) }}
             - name: GOSSIP_KEY
               valueFrom:
                 secretKeyRef:
+                {{- if .Values.global.gossipEncryption.autoGenerate }}
+                  name: {{ template "consul.fullname" . }}-gossip-encryption-key
+                  key: key
+                {{- else if (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
                   name: {{ .Values.global.gossipEncryption.secretName }}
                   key: {{ .Values.global.gossipEncryption.secretKey }}
+                {{- end }}
             {{- end }}
             {{- if (and .Values.server.enterpriseLicense.secretName .Values.server.enterpriseLicense.secretKey .Values.server.enterpriseLicense.enableLicenseAutoload (not .Values.global.acls.manageSystemACLs)) }}
             - name: CONSUL_LICENSE_PATH
@@ -252,7 +257,7 @@ spec:
                 {{- end }}
                 -datacenter={{ .Values.global.datacenter }} \
                 -data-dir=/consul/data \
-                {{- if (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
+                {{- if (or .Values.global.gossipEncryption.autoGenerate (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey)) }}
                 -encrypt="${GOSSIP_KEY}" \
                 {{- end }}
                 {{- if .Values.client.join }}

charts/consul/templates/gossip-encryption-autogenerate-job.yaml

@@ -0,0 +1,73 @@
+{{- if .Values.global.gossipEncryption.autoGenerate }}
+{{- if (or .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
+  {{ fail "If global.gossipEncryption.autoGenerate is true, global.gossipEncryption.secretName and global.gossipEncryption.secretKey must not be set." }}
+{{ end }}
+---
+# automatically generate encryption key for gossip protocol and save it in Kubernetes secret
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app: {{ template "consul.name" . }}
+    chart: {{ template "consul.chart" . }}
+    heritage: {{ .Release.Service }}
+    release: {{ .Release.Name }}
+  annotations:
+    "helm.sh/hook": pre-install,pre-upgrade
+    "helm.sh/hook-weight": "1"
+    "helm.sh/hook-delete-policy": hook-succeeded,before-hook-creation
+spec:
+  template:
+    metadata:
+      name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+      labels:
+        app: {{ template "consul.name" . }}
+        chart: {{ template "consul.chart" . }}
+        release: {{ .Release.Name }}
+        component: gossip-encryption-autogeneneration
+      annotations:
+        "consul.hashicorp.com/connect-inject": "false"
+    spec:
+      restartPolicy: Never
+      serviceAccountName: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+      securityContext:
+        runAsNonRoot: true
+        runAsGroup: 1000 
+        runAsUser: 100 
+        fsGroup: 1000
+      containers:
+        - name: gossip-encryption-autogen
+          image: "{{ .Values.global.image }}"
+          env:
+            - name: NAMESPACE
+              valueFrom:
+                fieldRef:
+                  fieldPath: metadata.namespace
+          workingDir: /tmp
+          # We're using POST requests below to create secrets via Kubernetes API.
+          # Note that in the subsequent runs of the job, POST requests will
+          # return a 409 because these secrets would already exist;
+          # we are ignoring these response codes.
+          command:
+            - "/bin/sh"
+            - "-ec"
+            - |
+              secretName={{ template "consul.fullname" . }}-gossip-encryption-key
+              secretKey=key
+              keyValue=$(consul keygen | base64)
+              curl -s -X POST --cacert /var/run/secrets/kubernetes.io/serviceaccount/ca.crt \
+                https://${KUBERNETES_SERVICE_HOST}:${KUBERNETES_SERVICE_PORT}/api/v1/namespaces/${NAMESPACE}/secrets \
+                -H "Authorization: Bearer $( cat /var/run/secrets/kubernetes.io/serviceaccount/token )" \
+                -H "Content-Type: application/json" \
+                -H "Accept: application/json" \
+                -d "{ \"kind\": \"Secret\", \"apiVersion\": \"v1\", \"metadata\": { \"name\": \"${secretName}\", \"namespace\": \"${NAMESPACE}\" }, \"type\": \"Opaque\", \"data\": { \"${secretKey}\": \"${keyValue}\" }}" > /dev/null
+          resources:
+            requests:
+              memory: "50Mi"
+              cpu: "50m"
+            limits:
+              memory: "50Mi"
+              cpu: "50m"
+{{- end }}

charts/consul/templates/gossip-encryption-autogenerate-podsecuritypolicy.yaml

@@ -0,0 +1,39 @@
+{{- if .Values.global.gossipEncryption.autoGenerate }}
+---
+apiVersion: policy/v1beta1
+kind: PodSecurityPolicy
+metadata:
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app: {{ template "consul.name" . }}
+    chart: {{ template "consul.chart" . }}
+    heritage: {{ .Release.Service }}
+    release: {{ .Release.Name }}
+  annotations:
+    "helm.sh/hook": pre-install,pre-upgrade
+    "helm.sh/hook-delete-policy": before-hook-creation
+spec:
+  privileged: false
+  # Required to prevent escalations to root.
+  allowPrivilegeEscalation: false
+  # This is redundant with non-root + disallow privilege escalation,
+  # but we can provide it for defense in depth.
+  requiredDropCapabilities:
+    - ALL
+  # Allow core volume types.
+  volumes:
+    - 'secret'
+  hostNetwork: false
+  hostIPC: false
+  hostPID: false
+  runAsUser:
+    rule: 'RunAsAny'
+  seLinux:
+    rule: 'RunAsAny'
+  supplementalGroups:
+    rule: 'RunAsAny'
+  fsGroup:
+    rule: 'RunAsAny'
+  readOnlyRootFilesystem: false
+{{- end }}

charts/consul/templates/gossip-encryption-autogenerate-role.yaml

@@ -0,0 +1,31 @@
+{{- if .Values.global.gossipEncryption.autoGenerate }}
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app: {{ template "consul.name" . }}
+    chart: {{ template "consul.chart" . }}
+    heritage: {{ .Release.Service }}
+    release: {{ .Release.Name }}
+  annotations:
+    "helm.sh/hook": pre-install,pre-upgrade
+    "helm.sh/hook-delete-policy": before-hook-creation
+rules:
+- apiGroups: [""]
+  resources:
+    - secrets
+  verbs:
+    - create
+    - get
+{{- if .Values.global.enablePodSecurityPolicies }}
+- apiGroups: ["policy"]
+  resources:
+  - podsecuritypolicies
+  verbs:
+    - use
+  resourceNames:
+    - {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+{{- end }}
+{{- end }}

charts/consul/templates/gossip-encryption-autogenerate-rolebinding.yaml

@@ -0,0 +1,22 @@
+{{- if .Values.global.gossipEncryption.autoGenerate }}
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app: {{ template "consul.name" . }}
+    chart: {{ template "consul.chart" . }}
+    heritage: {{ .Release.Service }}
+    release: {{ .Release.Name }}
+  annotations:
+    "helm.sh/hook": pre-install,pre-upgrade
+    "helm.sh/hook-delete-policy": before-hook-creation
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: Role
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+subjects:
+- kind: ServiceAccount
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+{{- end }}

charts/consul/templates/gossip-encryption-autogenerate-serviceaccount.yaml

@@ -0,0 +1,21 @@
+{{- if .Values.global.gossipEncryption.autoGenerate }}
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: {{ template "consul.fullname" . }}-gossip-encryption-autogenerate
+  namespace: {{ .Release.Namespace }}
+  labels:
+    app: {{ template "consul.name" . }}
+    chart: {{ template "consul.chart" . }}
+    heritage: {{ .Release.Service }}
+    release: {{ .Release.Name }}
+  annotations:
+    "helm.sh/hook": pre-install,pre-upgrade
+    "helm.sh/hook-delete-policy": before-hook-creation
+{{- with .Values.global.imagePullSecrets }}
+imagePullSecrets:
+{{- range . }}
+  - name: {{ .name }}
+{{- end }}
+{{- end }}
+{{- end }}

charts/consul/templates/server-statefulset.yaml

@@ -156,12 +156,17 @@ spec:
                   fieldPath: metadata.namespace
             - name: CONSUL_DISABLE_PERM_MGMT
               value: "true"
-            {{- if (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
+            {{- if (or .Values.global.gossipEncryption.autoGenerate (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey)) }}
             - name: GOSSIP_KEY
               valueFrom:
                 secretKeyRef:
+                {{- if .Values.global.gossipEncryption.autoGenerate }}
+                  name: {{ template "consul.fullname" . }}-gossip-encryption-key
+                  key: key
+                {{- else if (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
                   name: {{ .Values.global.gossipEncryption.secretName }}
                   key: {{ .Values.global.gossipEncryption.secretKey }}
+                {{- end }}
             {{- end }}
             {{- if .Values.global.tls.enabled }}
             - name: CONSUL_HTTP_ADDR
@@ -223,7 +228,7 @@ spec:
                 -datacenter={{ .Values.global.datacenter }} \
                 -data-dir=/consul/data \
                 -domain={{ .Values.global.domain }} \
-                {{- if (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey) }}
+                {{- if (or .Values.global.gossipEncryption.autoGenerate (and .Values.global.gossipEncryption.secretName .Values.global.gossipEncryption.secretKey)) }}
                 -encrypt="${GOSSIP_KEY}" \
                 {{- end }}
                 {{- if .Values.server.connect }}

charts/consul/test/acceptance/tests/basic/basic_test.go

@@ -1,15 +1,18 @@
 package basic
 
 import (
+	"context"
 	"fmt"
 	"strconv"
+	"strings"
 	"testing"
 
 	"github.com/hashicorp/consul-k8s/charts/consul/test/acceptance/framework/consul"
 	"github.com/hashicorp/consul-k8s/charts/consul/test/acceptance/framework/helpers"
 	"github.com/hashicorp/consul-k8s/charts/consul/test/acceptance/framework/logger"
 	"github.com/hashicorp/consul/api"
 	"github.com/stretchr/testify/require"
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 // Test that the basic installation, i.e. just
@@ -39,9 +42,10 @@ func TestBasicInstallation(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			releaseName := helpers.RandomName()
 			helmValues := map[string]string{
-				"global.acls.manageSystemACLs": strconv.FormatBool(c.secure),
-				"global.tls.enabled":           strconv.FormatBool(c.secure),
-				"global.tls.enableAutoEncrypt": strconv.FormatBool(c.autoEncrypt),
+				"global.acls.manageSystemACLs":         strconv.FormatBool(c.secure),
+				"global.tls.enabled":                   strconv.FormatBool(c.secure),
+				"global.gossipEncryption.autoGenerate": strconv.FormatBool(c.secure),
+				"global.tls.enableAutoEncrypt":         strconv.FormatBool(c.autoEncrypt),
 			}
 			consulCluster := consul.NewHelmCluster(t, helmValues, suite.Environment().DefaultContext(t), suite.Config(), releaseName)
 
@@ -63,6 +67,23 @@ func TestBasicInstallation(t *testing.T) {
 			kv, _, err := client.KV().Get(randomKey, nil)
 			require.NoError(t, err)
 			require.Equal(t, kv.Value, randomValue)
+
+			// Check that autogenerated gossip encryption key is being used
+			if c.secure {
+				secretName := fmt.Sprintf("%s-consul-gossip-encryption-key", releaseName)
+				secretKey := "key"
+
+				keyring, err := client.Operator().KeyringList(nil)
+				require.NoError(t, err)
+
+				testContext := suite.Environment().DefaultContext(t)
+				secret, err := testContext.KubernetesClient(t).CoreV1().Secrets(testContext.KubectlOptions(t).Namespace).Get(context.Background(), secretName, v1.GetOptions{})
+				require.NoError(t, err)
+				gossipEncryptionKey := strings.TrimSpace(string(secret.Data[secretKey]))
+
+				require.Len(t, keyring, 2)
+				require.Contains(t, keyring[0].Keys, gossipEncryptionKey)
+			}
 		})
 	}
 }

charts/consul/test/unit/client-daemonset.bats

@@ -606,6 +606,26 @@ load _helpers
   [ "${actual}" = "" ]
 }
 
+@test "client/DaemonSet: gossip encryption autogeneration properly sets secretName and secretKey" {
+  cd `chart_dir`
+  local actual=$(helm template \
+    -s templates/client-daemonset.yaml  \
+    --set 'global.gossipEncryption.autoGenerate=true' \
+    . | tee /dev/stderr |
+    yq '.spec.template.spec.containers[] | select(.name=="consul") | .env[] | select(.name == "GOSSIP_KEY") | .valueFrom.secretKeyRef | [.name=="RELEASE-NAME-consul-gossip-encryption-key", .key="key"] | all' | tee /dev/stderr)
+  [ "${actual}" = "true" ]
+}
+
+@test "client/DaemonSet: gossip encryption key is passed in via the -encrypt flag" {
+  cd `chart_dir`
+  local actual=$(helm template \
+    -s templates/client-daemonset.yaml  \
+    --set 'global.gossipEncryption.autoGenerate=true' \
+    . | tee /dev/stderr |
+    yq '.spec.template.spec.containers[] | select(.name=="consul") | .command | any(contains("-encrypt=\"${GOSSIP_KEY}\""))' | tee /dev/stderr)
+  [ "${actual}" = "true" ]
+}
+
 @test "client/DaemonSet: gossip encryption disabled in client DaemonSet when secretName is missing" {
   cd `chart_dir`
   local actual=$(helm template \