Istiod is structured as a modular monolith, housing a wide range of functionality from certificate signing, proxy configuration (XDS), traditional Kubernetes controllers, and more.

## Proxy Configuration

Istiod's primary role - and most code - is to dynamically configure proxies (Envoy sidecars and ingress, gRPC, ztunnel, and more). This roughly consists of 3 parts:
1. Config ingestion (inputs to the system)
1. Config translation
1. Config serving (XDS)

  experimental:
    stableValidationPolicy: false
  global:
    # Used to locate istiod.
    istioNamespace: istio-system
    # List of cert-signers to allow "approve" action in the istio cluster role
    #
    # certSigners:
    #   - clusterissuers.cert-manager.io/istio-ca
    certSigners: []
    # enable pod disruption budget for the control plane, which is used to

apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: istiod{{- if not (eq .Values.revision "")}}-{{ .Values.revision }}{{- end }}
  namespace: {{ .Values.global.istioNamespace }}
  labels:
    app: istiod
    release: {{ .Release.Name }}
rules:
# permissions to verify the webhook is ready and rejecting
# invalid config. We use --server-dry-run so no config is persisted.
- apiGroups: ["networking.istio.io"]
  verbs: ["create"]

    install.operator.istio.io/owning-resource: {{ .Values.ownerName | default "unknown" }}
    operator.istio.io/component: "IngressGateways"
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: Role
  name: {{ $gateway.name }}-sds
subjects:
- kind: ServiceAccount
  name: {{ $gateway.name }}-service-account

ldap:
  existingSecret: true
env:
  GF_SECURITY_ADMIN_USER: "admin"
  GF_SECURITY_ADMIN_PASSWORD: "admin"
  GF_AUTH_BASIC_ENABLED: "false"
  GF_AUTH_ANONYMOUS_ENABLED: "true"
  GF_AUTH_ANONYMOUS_ORG_ROLE: Admin

# Expose on port 3000 to match the Istio docs
service:
  port: 3000

securityContext: null

# Set up out dashboards
dashboardProviders:
  dashboardproviders.yaml:
    apiVersion: 1

  resourceNames: ["privileged"]
  verbs: ["use"]
{{- end }}
---
{{- if .Values.cni.repair.enabled }}
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: istio-cni-repair-role
  labels:
    app: istio-cni
    release: {{ .Release.Name }}
    istio.io/rev: {{ .Values.revision | default "default" }}
    install.operator.istio.io/owning-resource: {{ .Values.ownerName | default "unknown" }}

func mustGetClusterRole(g *WithT, objs *ObjectSet, name string) *object.K8sObject {
	obj := objs.kind(name2.ClusterRoleStr).nameEquals(name)
	g.Expect(obj).Should(Not(BeNil()))
	return obj
}

// mustGetRole returns the role with the given name or fails if it's not found in objs.
func mustGetRole(g *WithT, objs *ObjectSet, name string) *object.K8sObject {
	obj := objs.kind(name2.RoleStr).nameEquals(name)
	g.Expect(obj).Should(Not(BeNil()))

	}

	values := fmt.Sprintf(`
global:
  istioNamespace: %s
`, opt.Namespace)

	// Render the templates required for the service account and role bindings.
	baseContent, err := baseRenderer.RenderManifestFiltered(values, func(template string) bool {
		for _, t := range baseTemplates {
			if strings.Contains(template, t) {
				return true
			}
		}