Add support for using delegated domains for DNS-01

cmd/root.go

@@ -35,6 +35,8 @@ func init() {
 	fs.String("service-name", "", "NamespacedName of the Contour LoadBalancer Service")
 	fs.String("default-issuer-name", "", "Issuer name used by default")
 	fs.String("default-issuer-kind", controllers.ClusterIssuerKind, "Issuer kind used by default")
+	fs.String("default-delegated-domain", "", "Delegated domain used by default")
+	fs.Bool("allow-custom-delegations", false, "Allow custom delegated domains via annotations")
 	fs.Uint("csr-revision-limit", 0, "Maximum number of CertificateRequest revisions to keep")
 	fs.String("ingress-class-name", "", "Ingress class name that watched by Contour Plus. If not specified, then all classes are watched")
 	fs.Bool("leader-election", true, "Enable/disable leader election")
@@ -60,15 +62,17 @@ var rootCmd = &cobra.Command{
 
 In addition to flags, the following environment variables are read:
 
-	CP_METRICS_ADDR          Bind address for the metrics endpoint
-	CP_CRDS                  Comma-separated list of CRD names
-	CP_NAME_PREFIX           Prefix of CRD names to be created
-	CP_SERVICE_NAME          NamespacedName of the Contour LoadBalancer Service
-	CP_DEFAULT_ISSUER_NAME   Issuer name used by default
-	CP_DEFAULT_ISSUER_KIND   Issuer kind used by default
-	CP_CSR_REVISION_LIMIT    Maximum number of CertificateRequest revisions to keep
-	CP_LEADER_ELECTION       Disable leader election if set to "false"
-	CP_INGRESS_CLASS_NAME    Ingress class name that watched by Contour Plus. If not specified, then all classes are watched`,
+	CP_METRICS_ADDR             Bind address for the metrics endpoint
+	CP_CRDS                     Comma-separated list of CRD names
+	CP_NAME_PREFIX              Prefix of CRD names to be created
+	CP_SERVICE_NAME             NamespacedName of the Contour LoadBalancer Service
+	CP_DEFAULT_ISSUER_NAME      Issuer name used by default
+	CP_DEFAULT_ISSUER_KIND      Issuer kind used by default
+	CP_DEFAULT_DELEGATED_DOMAIN Delegation domain used by default
+	CP_ALLOW_CUSTOM_DELEGATIONS Allow custom delegated domains via annotations
+	CP_CSR_REVISION_LIMIT       Maximum number of CertificateRequest revisions to keep
+	CP_LEADER_ELECTION          Disable leader election if set to "false"
+	CP_INGRESS_CLASS_NAME       Ingress class name that watched by Contour Plus. If not specified, then all classes are watched`,
 	RunE: func(cmd *cobra.Command, args []string) error {
 		cmd.SilenceUsage = true
 		return run()

controllers/httpproxy_controller.go

@@ -3,6 +3,7 @@ package controllers
 import (
 	"context"
 	"net"
+	"strings"
 
 	"github.com/go-logr/logr"
 	projectcontourv1 "github.com/projectcontour/contour/apis/projectcontour/v1"
@@ -26,22 +27,25 @@ const (
 	clusterIssuerNameAnnotation       = "cert-manager.io/cluster-issuer"
 	ingressClassNameAnnotation        = "kubernetes.io/ingress.class"
 	contourIngressClassNameAnnotation = "projectcontour.io/ingress.class"
+	delegatedDomainAnnotation         = "contour-plus.cybozu.com/delegated-domain"
 )
 
 // HTTPProxyReconciler reconciles a HTTPProxy object
 type HTTPProxyReconciler struct {
 	client.Client
-	Log               logr.Logger
-	Scheme            *runtime.Scheme
-	ServiceKey        client.ObjectKey
-	IssuerKey         client.ObjectKey
-	Prefix            string
-	DefaultIssuerName string
-	DefaultIssuerKind string
-	CSRRevisionLimit  uint
-	CreateDNSEndpoint bool
-	CreateCertificate bool
-	IngressClassName  string
+	Log                    logr.Logger
+	Scheme                 *runtime.Scheme
+	ServiceKey             client.ObjectKey
+	IssuerKey              client.ObjectKey
+	Prefix                 string
+	DefaultIssuerName      string
+	DefaultIssuerKind      string
+	DefaultDelegatedDomain string
+	AllowCustomDelegations bool
+	CSRRevisionLimit       uint
+	CreateDNSEndpoint      bool
+	CreateCertificate      bool
+	IngressClassName       string
 }
 
 // +kubebuilder:rbac:groups=projectcontour.io,resources=httpproxies,verbs=get;list;watch
@@ -89,6 +93,11 @@ func (r *HTTPProxyReconciler) Reconcile(ctx context.Context, req ctrl.Request) (
 		return ctrl.Result{}, err
 	}
 
+	if err := r.reconcileDelegationDNSEndpoint(ctx, hp, log); err != nil {
+		log.Error(err, "unable to reconcile delegation DNSEndpoint")
+		return ctrl.Result{}, err
+	}
+
 	if err := r.reconcileCertificate(ctx, hp, log); err != nil {
 		log.Error(err, "unable to reconcile Certificate")
 		return ctrl.Result{}, err
@@ -182,6 +191,51 @@ func (r *HTTPProxyReconciler) reconcileDNSEndpoint(ctx context.Context, hp *proj
 	return nil
 }
 
+func (r *HTTPProxyReconciler) reconcileDelegationDNSEndpoint(ctx context.Context, hp *projectcontourv1.HTTPProxy, log logr.Logger) error {
+	if !r.CreateDNSEndpoint {
+		return nil
+	}
+
+	delegatedDomain := r.DefaultDelegatedDomain
+	if hp.Annotations[delegatedDomainAnnotation] != "" && r.AllowCustomDelegations {
+		delegatedDomain = hp.Annotations[delegatedDomainAnnotation]
+	}
+
+	if delegatedDomain == "" {
+		return nil
+	}
+
+	if hp.Spec.VirtualHost == nil {
+		return nil
+	}
+	fqdn := hp.Spec.VirtualHost.Fqdn
+	if len(fqdn) == 0 {
+		return nil
+	}
+
+	obj := &unstructured.Unstructured{}
+	obj.SetGroupVersionKind(externalDNSGroupVersion.WithKind(DNSEndpointKind))
+	obj.SetName(r.Prefix + hp.Name + "-delegation")
+	obj.SetNamespace(hp.Namespace)
+	obj.UnstructuredContent()["spec"] = map[string]interface{}{
+		"endpoints": makeDelegationEndpoint(fqdn, delegatedDomain),
+	}
+
+	if err := ctrl.SetControllerReference(hp, obj, r.Scheme); err != nil {
+		return err
+	}
+
+	if err := r.Patch(ctx, obj, client.Apply, &client.PatchOptions{
+		Force:        ptr.To(true),
+		FieldManager: "contour-plus",
+	}); err != nil {
+		return err
+	}
+
+	log.Info("Delegation DNSEndpoint successfully reconciled")
+	return nil
+}
+
 func (r *HTTPProxyReconciler) reconcileCertificate(ctx context.Context, hp *projectcontourv1.HTTPProxy, log logr.Logger) error {
 	if !r.CreateCertificate {
 		return nil
@@ -336,3 +390,15 @@ func ipsToTargets(ips []net.IP) ([]string, []string) {
 	}
 	return ipv4Targets, ipv6Targets
 }
+
+func makeDelegationEndpoint(hostname, delegatedDomain string) []map[string]interface{} {
+	fqdn := strings.Trim(hostname, ".")
+	return []map[string]interface{}{
+		{
+			"dnsName":    "_acme-challenge." + fqdn,
+			"targets":    []string{"_acme-challenge." + fqdn + "." + delegatedDomain},
+			"recordType": "CNAME",
+			"recordTTL":  3600,
+		},
+	}
+}