cmd/k8s-operator: optionally update dnsrecords Configmap with DNS records for proxies.

This commit adds functionality to automatically populate
DNS records for the in-cluster ts.net nameserver
to allow cluster workloads to resolve MagicDNS names
associated with operator's proxies.

The records are created as follows:
* For tailscale Ingress proxies there will be
a record mapping the MagicDNS name of the Ingress
device and each proxy Pod's IP address.
* For cluster egress proxies, configured via
tailscale.com/tailnet-fqdn annotation, there will be
a record for each proxy Pod, mapping
the MagicDNS name of the exposed
tailnet workload to the proxy Pod's IP.

No records will be created for any other proxy types.
Records will only be created if users have configured
the operator to deploy an in-cluster ts.net nameserver
by applying tailscale.com/v1alpha1.DNSConfig.

It is user's responsibility to add the ts.net nameserver
as a stub nameserver for ts.net DNS names.
https://kubernetes.io/docs/tasks/administer-cluster/dns-custom-nameservers/#configuration-of-stub-domain-and-upstream-nameserver-using-coredns
https://cloud.google.com/kubernetes-engine/docs/how-to/kube-dns#upstream_nameservers

See also https://github.com/tailscale/tailscale/pull/11017

Updates tailscale/tailscale#10499

Signed-off-by: Irbe Krumina <irbe@tailscale.com>
This commit is contained in:
Irbe Krumina 2024-02-02 18:54:53 +00:00
parent 9eaa56df93
commit dd28a4a53c
14 changed files with 705 additions and 31 deletions

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@ -36,7 +36,6 @@ const (
// provided by a mounted Kubernetes Configmap. The Configmap mounted at
// /config is the only supported way for configuring this nameserver.
defaultDNSConfigDir = "/config"
defaultDNSFile = "dns.json"
kubeletMountedConfigLn = "..data"
)
@ -324,9 +323,9 @@ func ensureWatcherForKubeConfigMap(ctx context.Context) chan string {
type configReaderFunc func() ([]byte, error)
// configMapConfigReader reads the desired nameserver configuration from a
// dns.json file in a ConfigMap mounted at /config.
// records.json file in a ConfigMap mounted at /config.
var configMapConfigReader configReaderFunc = func() ([]byte, error) {
if contents, err := os.ReadFile(filepath.Join(defaultDNSConfigDir, defaultDNSFile)); err == nil {
if contents, err := os.ReadFile(filepath.Join(defaultDNSConfigDir, operatorutils.DNSRecordsCMKey)); err == nil {
return contents, nil
} else if os.IsNotExist(err) {
return nil, nil

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@ -53,6 +53,9 @@ rules:
- apiGroups: ["apps"]
resources: ["statefulsets", "deployments"]
verbs: ["*"]
- apiGroups: ["discovery.k8s.io"]
resources: ["endpointslices"]
verbs: ["get", "list", "watch"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding

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@ -0,0 +1,9 @@
apiVersion: tailscale.com/v1alpha1
kind: DNSConfig
metadata:
name: ts-dns
spec:
nameserver:
image:
repo: gcr.io/csi-test-290908/nameserver
tag: v0.0.1ns

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@ -1,4 +1,4 @@
apiVersion: v1
kind: ConfigMap
metadata:
name: dnsconfig
name: dnsrecords

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@ -26,12 +26,12 @@ spec:
protocol: UDP
containerPort: 1053
volumeMounts:
- name: dnsconfig
- name: dnsrecords
mountPath: /config
restartPolicy: Always
serviceAccount: nameserver
serviceAccountName: nameserver
volumes:
- name: dnsconfig
- name: dnsrecords
configMap:
name: dnsconfig
name: dnsrecords

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@ -2,5 +2,3 @@ apiVersion: v1
kind: ServiceAccount
metadata:
name: nameserver
imagePullSecrets:
- name: foo

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@ -833,6 +833,14 @@ rules:
- deployments
verbs:
- '*'
- apiGroups:
- discovery.k8s.io
resources:
- endpointslices
verbs:
- get
- list
- watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role

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@ -0,0 +1,335 @@
// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
//go:build !plan9
// tailscale-operator provides a way to expose services running in a Kubernetes
// cluster to your Tailnet and to make Tailscale nodes available to cluster
// workloads
package main
import (
"context"
"encoding/json"
"fmt"
"slices"
"go.uber.org/zap"
corev1 "k8s.io/api/core/v1"
discoveryv1 "k8s.io/api/discovery/v1"
networkingv1 "k8s.io/api/networking/v1"
apiequality "k8s.io/apimachinery/pkg/api/equality"
apierrors "k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/types"
"k8s.io/utils/net"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/reconcile"
operatorutils "tailscale.com/k8s-operator"
tsapi "tailscale.com/k8s-operator/apis/v1alpha1"
"tailscale.com/util/mak"
)
const (
dnsRecordsRecocilerFinalizer = "tailscale.com/dns-records-reconciler"
annotationTSMagicDNSName = "tailscale.com/magic-dnsname"
)
// dnsRecordsReconciler knows how to update dnsrecords ConfigMap with DNS
// records.
// The records that it creates are:
// - For tailscale Ingress, a mapping of the Ingress's MagicDNSName to the IP address of
// the ingress proxy Pod.
// - For egress proxies configured via tailscale.com/tailnet-fqdn annotation, a
// mapping of the the tailnet FQDN to the IP address of the egress proxy Pod.
//
// Records will only created if there is exactly one ready
// tailscale.com/v1alpha1.DNSConfig instance in the cluster (so that we know
// that there is a ts.net nameserver deployed in the cluster).
type dnsRecordsReconciler struct {
client.Client
tsNamespace string // namespace in which we provision tailscale resources
logger *zap.SugaredLogger
isDefaultLoadBalancer bool // true if operator is the default ingress controller in this cluster
}
// Reconcile takes a reconcile.Request for a headless Service fronting a
// tailscale proxy and updates DNS Records in dnsrecords ConfigMap for the
// in-cluster ts.net nameserver if required.
func (dnsRR *dnsRecordsReconciler) Reconcile(ctx context.Context, req reconcile.Request) (res reconcile.Result, err error) {
logger := dnsRR.logger.With("Service", req.NamespacedName)
logger.Debugf("starting reconcile")
defer logger.Debugf("reconcile finished")
headlessSvc := new(corev1.Service)
err = dnsRR.Client.Get(ctx, req.NamespacedName, headlessSvc)
if apierrors.IsNotFound(err) {
logger.Debugf("Service not found")
return reconcile.Result{}, nil
}
if err != nil {
return reconcile.Result{}, fmt.Errorf("failed to get Service: %w", err)
}
if !(isManagedByType(headlessSvc, "svc") || isManagedByType(headlessSvc, "ingress")) {
logger.Debugf("Service is not a headless Service for a tailscale ingress or egress proxy; do nothing")
return reconcile.Result{}, nil
}
if !headlessSvc.DeletionTimestamp.IsZero() {
logger.Debug("Service is being deleted, clean up resources")
return reconcile.Result{}, dnsRR.maybeCleanup(ctx, headlessSvc, logger)
}
// Check that there is a ts.net nameserver deployed to the cluster by
// checking that there is a ready tailscale.com/v1alpha1.DNSConfig
// resource.
dnsCfgLst := new(tsapi.DNSConfigList)
if err = dnsRR.List(ctx, dnsCfgLst); err != nil {
return reconcile.Result{}, fmt.Errorf("error listing DNSConfigs: %w", err)
}
if len(dnsCfgLst.Items) == 0 {
logger.Debugf("DNSConfig does not exist, not creating DNS records")
return reconcile.Result{}, nil
}
if len(dnsCfgLst.Items) > 1 {
logger.Errorf("Invalid cluster state - more than one DNSConfig found in cluster. Please ensure no more than one exists")
return reconcile.Result{}, nil
}
dnsCfg := dnsCfgLst.Items[0]
if !operatorutils.DNSCfgIsReady(&dnsCfg) {
logger.Info("DNSConfig is not ready yet, waiting...")
return reconcile.Result{}, nil
}
return reconcile.Result{}, dnsRR.maybeProvision(ctx, headlessSvc, logger)
}
// maybeProvision ensures that dnsrecords ConfigMap contains a record for the
// proxy associated with the headless Service.
// The record is only provisioned if the proxy is for a tailscale Ingress or
// egress configured via tailscale.com/tailnet-fqdn annotation.
//
// For Ingress, the record is a mapping between the MagicDNSName of the Ingress, retrieved from
// ingress.status.loadBalancer.ingress.hostname field and the proxy Pod IP addresses
// retrieved from the EndpoinSlice associated with this headless Service, i.e
// Records{IP4: <MagicDNS name of the Ingress>: <[IPs of the ingress proxy Pods]>}
//
// For egress, the record is a mapping between tailscale.com/tailnet-fqdn
// annotation and the proxy Pod IP addresses, retrieved from the EndpointSlice
// associated with this headless Service, i.e
// Records{IP4: {<tailscale.com/tailnet-fqdn>: <[IPs of the egress proxy Pods]>}
//
// If records need to be created for this proxy, maybeProvision will also:
// - update the headless Service with a tailscale.com/magic-dnsname annotation
// - update the headless Service with a finalizer
func (dnsRR *dnsRecordsReconciler) maybeProvision(ctx context.Context, headlessSvc *corev1.Service, logger *zap.SugaredLogger) error {
if headlessSvc == nil {
logger.Info("[unexpected] maybeProvision called with a nil Service")
return nil
}
isEgressFQDNSvc, err := dnsRR.isSvcForFQDNEgressProxy(ctx, headlessSvc)
if err != nil {
return fmt.Errorf("error checking whether Service is for an egress proxy: %w", err)
}
if !(isEgressFQDNSvc || isManagedByType(headlessSvc, "ingress")) {
logger.Debug("Service is not fronting a proxy that we create DNS records for; do nothing")
return nil
}
fqdn, err := dnsRR.fqdnForDNSRecord(ctx, headlessSvc, logger)
if err != nil {
return fmt.Errorf("error determining DNS name for record: %w", err)
}
if fqdn == "" {
logger.Debugf("MagicDNS name does not (yet) exist, not provisioning DNS record")
return nil // a new reconcile will be triggered once it's added
}
oldHeadlessSvc := headlessSvc.DeepCopy()
// Ensure that headless Service is annotated with a finalizer to help
// with records cleanup when proxy resources are deleted.
if !slices.Contains(headlessSvc.Finalizers, dnsRecordsRecocilerFinalizer) {
headlessSvc.Finalizers = append(headlessSvc.Finalizers, dnsRecordsRecocilerFinalizer)
}
// Ensure that headless Service is annotated with the current MagicDNS
// name to help with records cleanup when proxy resources are deleted or
// MagicDNS name changes.
oldFqdn := headlessSvc.Annotations[annotationTSMagicDNSName]
if oldFqdn != "" && oldFqdn != fqdn { // i.e user has changed the value of tailscale.com/tailnet-fqdn annotation
logger.Debugf("MagicDNS name has changed, remvoving record for %s", oldFqdn)
updateFunc := func(rec *operatorutils.Records) {
delete(rec.IP4, oldFqdn)
}
if err = dnsRR.updateDNSConfig(ctx, updateFunc); err != nil {
return fmt.Errorf("error removing record for %s: %w", oldFqdn, err)
}
}
mak.Set(&headlessSvc.Annotations, annotationTSMagicDNSName, fqdn)
if !apiequality.Semantic.DeepEqual(oldHeadlessSvc, headlessSvc) {
logger.Infof("provisioning DNS record for MagicDNS name: %s", fqdn) // this will be printed exactly once
if err := dnsRR.Update(ctx, headlessSvc); err != nil {
return fmt.Errorf("error updating proxy headless Service metadata: %w", err)
}
}
// Get the Pod IP addresses for the proxy from the EndpointSlice for the
// headless Service.
labels := map[string]string{discoveryv1.LabelServiceName: headlessSvc.Name} // https://kubernetes.io/docs/concepts/services-networking/endpoint-slices/#ownership
eps, err := getSingleObject[discoveryv1.EndpointSlice](ctx, dnsRR.Client, dnsRR.tsNamespace, labels)
if err != nil {
return fmt.Errorf("error getting proxy EndpointSlice: %w", err)
}
if eps == nil {
logger.Debugf("proxy EndpointSlice does not yet exist. We will reconcile again once it's created")
return nil
}
ips := make([]string, 0)
for _, ep := range eps.Endpoints {
for _, ip := range ips {
if !net.IsIPv4String(ip) {
logger.Infof("EndpointSlice contains IP address %q that is not IPv4, ignoring. Currently only IPv4 is supported", ip)
} else {
ips = append(ips, ip)
}
}
ips = append(ips, ep.Addresses...)
}
if len(ips) == 0 {
logger.Debugf("No endpoint addresses found. We will reconcile again once they are created.")
return nil
}
updateFunc := func(rec *operatorutils.Records) {
mak.Set(&rec.IP4, fqdn, ips)
}
if err = dnsRR.updateDNSConfig(ctx, updateFunc); err != nil {
return fmt.Errorf("error updating DNS records: %w", err)
}
return nil
}
// maybeCleanup ensures that the DNS record for the proxy has been removed from
// dnsrecords ConfigMap and the tailscale.com/dns-records-reconciler finalizer
// has been removed from the Service. If the record is not found in the
// ConfigMap, the ConfigMap does not exist or the Service does not have
// tailscale.com/magic-dnsname annotation, just remove the finalizer.
func (h *dnsRecordsReconciler) maybeCleanup(ctx context.Context, headlessSvc *corev1.Service, logger *zap.SugaredLogger) error {
ix := slices.Index(headlessSvc.Finalizers, dnsRecordsRecocilerFinalizer)
if ix == -1 {
logger.Debugf("no finalizer, nothing to do")
return nil
}
cm := &corev1.ConfigMap{}
err := h.Client.Get(ctx, types.NamespacedName{Name: operatorutils.DNSRecordsCMName, Namespace: h.tsNamespace}, cm)
if apierrors.IsNotFound(err) {
logger.Debug("dsnrecords ConfigMap not found")
return h.removeHeadlessSvcFinalizer(ctx, headlessSvc)
}
if err != nil {
return fmt.Errorf("error retrieving dnsrecords ConfigMap: %w", err)
}
if cm.Data == nil {
logger.Debug("dnsrecords ConfigMap contains no records")
return h.removeHeadlessSvcFinalizer(ctx, headlessSvc)
}
_, ok := cm.Data[operatorutils.DNSRecordsCMKey]
if !ok {
logger.Debug("dnsrecords ConfigMap contains no records")
return h.removeHeadlessSvcFinalizer(ctx, headlessSvc)
}
fqdn, ok := headlessSvc.GetAnnotations()[annotationTSMagicDNSName]
if !ok || fqdn == "" {
return h.removeHeadlessSvcFinalizer(ctx, headlessSvc)
}
logger.Infof("removing DNS record for MagicDNS name %s", fqdn)
updateFunc := func(rec *operatorutils.Records) {
delete(rec.IP4, fqdn)
}
if err = h.updateDNSConfig(ctx, updateFunc); err != nil {
return fmt.Errorf("error updating DNS config: %w", err)
}
return h.removeHeadlessSvcFinalizer(ctx, headlessSvc)
}
func (dnsRR *dnsRecordsReconciler) removeHeadlessSvcFinalizer(ctx context.Context, headlessSvc *corev1.Service) error {
idx := slices.Index(headlessSvc.Finalizers, dnsRecordsRecocilerFinalizer)
if idx == -1 {
return nil
}
headlessSvc.Finalizers = append(headlessSvc.Finalizers[:idx], headlessSvc.Finalizers[idx+1:]...)
return dnsRR.Update(ctx, headlessSvc)
}
// fqdnForDNSRecord returns MagicDNS name associated with a given headless Service.
// If the headless Service is for a tailscale Ingress proxy, returns ingress.status.loadBalancer.ingress.hostname.
// If the headless Service is for an tailscale egress proxy configured via tailscale.com/tailnet-fqdn annotation, returns the annotation value.
// This function is not expected to be called with headless Services for other
// proxy types, or any other Services, but it just returns an empty string if
// that happens.
func (dnsRR *dnsRecordsReconciler) fqdnForDNSRecord(ctx context.Context, headlessSvc *corev1.Service, logger *zap.SugaredLogger) (string, error) {
parentName := parentFromObjectLabels(headlessSvc)
if isManagedByType(headlessSvc, "ingress") {
ing := new(networkingv1.Ingress)
if err := dnsRR.Get(ctx, parentName, ing); err != nil {
return "", err
}
if len(ing.Status.LoadBalancer.Ingress) == 0 {
return "", nil
}
return ing.Status.LoadBalancer.Ingress[0].Hostname, nil
}
if isManagedByType(headlessSvc, "svc") {
svc := new(corev1.Service)
if err := dnsRR.Get(ctx, parentName, svc); apierrors.IsNotFound(err) {
logger.Info("[unexpected] parent Service for egress proxy %s not found", headlessSvc.Name)
return "", nil
} else if err != nil {
return "", err
}
return svc.Annotations[AnnotationTailnetTargetFQDN], nil
}
return "", nil
}
// updateDNSConfig runs the provided update function against dnsrecords
// ConfigMap. At this point the in-cluster ts.net nameserver is expected to be
// successfully created together with the ConfigMap.
func (dnsRR *dnsRecordsReconciler) updateDNSConfig(ctx context.Context, update func(*operatorutils.Records)) error {
cm := &corev1.ConfigMap{}
err := dnsRR.Get(ctx, types.NamespacedName{Name: operatorutils.DNSRecordsCMName, Namespace: dnsRR.tsNamespace}, cm)
if apierrors.IsNotFound(err) {
dnsRR.logger.Info("[unexpected] dnsrecords ConfigMap not found in cluster. Not updating DNS records. Please open an isue and attach operator logs.")
return nil
}
if err != nil {
return fmt.Errorf("error retrieving dnsrecords ConfigMap: %w", err)
}
dnsRecords := operatorutils.Records{Version: operatorutils.Alpha1Version, IP4: map[string][]string{}}
if cm.Data != nil && cm.Data[operatorutils.DNSRecordsCMKey] != "" {
if err := json.Unmarshal([]byte(cm.Data[operatorutils.DNSRecordsCMKey]), &dnsRecords); err != nil {
return err
}
}
update(&dnsRecords)
dnsRecordsBs, err := json.Marshal(dnsRecords)
if err != nil {
return fmt.Errorf("error marshalling DNS records: %w", err)
}
mak.Set(&cm.Data, operatorutils.DNSRecordsCMKey, string(dnsRecordsBs))
return dnsRR.Update(ctx, cm)
}
// isSvcForFQDNEgressProxy returns true if the Service is a headless Service
// created for a proxy for a tailscale egress Service configured via
// tailscale.com/tailnet-fqdn annotation.
func (dnsRR *dnsRecordsReconciler) isSvcForFQDNEgressProxy(ctx context.Context, svc *corev1.Service) (bool, error) {
if !isManagedByType(svc, "svc") {
return false, nil
}
parentName := parentFromObjectLabels(svc)
parentSvc := new(corev1.Service)
if err := dnsRR.Get(ctx, parentName, parentSvc); apierrors.IsNotFound(err) {
return false, nil
} else if err != nil {
return false, err
}
annots := parentSvc.Annotations
return annots != nil && annots[AnnotationTailnetTargetFQDN] != "", nil
}

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@ -0,0 +1,198 @@
// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
//go:build !plan9
package main
import (
"context"
"encoding/json"
"testing"
"github.com/google/go-cmp/cmp"
"go.uber.org/zap"
corev1 "k8s.io/api/core/v1"
discoveryv1 "k8s.io/api/discovery/v1"
networkingv1 "k8s.io/api/networking/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/types"
"sigs.k8s.io/controller-runtime/pkg/client"
"sigs.k8s.io/controller-runtime/pkg/client/fake"
operatorutils "tailscale.com/k8s-operator"
tsapi "tailscale.com/k8s-operator/apis/v1alpha1"
"tailscale.com/tstest"
"tailscale.com/types/ptr"
)
func TestDNSRecordsReconciler(t *testing.T) {
// Preconfigure a cluster with a DNSConfig
dnsConfig := &tsapi.DNSConfig{
ObjectMeta: metav1.ObjectMeta{
Name: "test",
},
TypeMeta: metav1.TypeMeta{Kind: "DNSConfig"},
Spec: tsapi.DNSConfigSpec{
Nameserver: &tsapi.Nameserver{},
}}
ing := &networkingv1.Ingress{
ObjectMeta: metav1.ObjectMeta{
Name: "ts-ingress",
Namespace: "test",
},
Spec: networkingv1.IngressSpec{
IngressClassName: ptr.To("tailscale"),
},
Status: networkingv1.IngressStatus{
LoadBalancer: networkingv1.IngressLoadBalancerStatus{
Ingress: []networkingv1.IngressLoadBalancerIngress{{
Hostname: "cluster.ingress.ts.net"}},
},
},
}
cm := &corev1.ConfigMap{ObjectMeta: metav1.ObjectMeta{Name: "dnsrecords", Namespace: "tailscale"}}
fc := fake.NewClientBuilder().
WithScheme(tsapi.GlobalScheme).
WithObjects(cm).
WithObjects(dnsConfig).
WithObjects(ing).
WithStatusSubresource(dnsConfig, ing).
Build()
zl, err := zap.NewDevelopment()
if err != nil {
t.Fatal(err)
}
cl := tstest.NewClock(tstest.ClockOpts{})
// Set the ready condition of the DNSConfig
mustUpdateStatus[tsapi.DNSConfig](t, fc, "", "test", func(c *tsapi.DNSConfig) {
operatorutils.SetDNSConfigCondition(c, tsapi.NameserverReady, metav1.ConditionTrue, reasonNameserverCreated, reasonNameserverCreated, 0, cl, zl.Sugar())
})
dnsRR := &dnsRecordsReconciler{
Client: fc,
logger: zl.Sugar(),
tsNamespace: "tailscale",
}
// 1. DNS record is created for an egress proxy configured via
// tailscale.com/tailnet-fqdn annotation
egressSvcFQDN := &corev1.Service{
ObjectMeta: metav1.ObjectMeta{
Name: "egress-fqdn",
Namespace: "test",
Annotations: map[string]string{"tailscale.com/tailnet-fqdn": "foo.bar.ts.net"},
},
Spec: corev1.ServiceSpec{
ExternalName: "unused",
Type: corev1.ServiceTypeExternalName,
},
}
headlessForEgressSvcFQDN := headlessSvcForParent(egressSvcFQDN, "svc") // create the proxy headless Service
ep := endpointSliceForService(headlessForEgressSvcFQDN, "10.9.8.7")
mustCreate(t, fc, egressSvcFQDN)
mustCreate(t, fc, headlessForEgressSvcFQDN)
mustCreate(t, fc, ep)
expectReconciled(t, dnsRR, "tailscale", "egress-fqdn") // dns-records-reconciler reconcile the headless Service
// ConfigMap should now have a record for foo.bar.ts.net -> 10.8.8.7
wantHosts := map[string][]string{"foo.bar.ts.net": {"10.9.8.7"}}
expectHostsRecords(t, fc, wantHosts)
// 2. DNS record is updated if tailscale.com/tailnet-fqdn annotation's
// value changes
mustUpdate(t, fc, "test", "egress-fqdn", func(svc *corev1.Service) {
svc.Annotations["tailscale.com/tailnet-fqdn"] = "baz.bar.ts.net"
})
expectReconciled(t, dnsRR, "tailscale", "egress-fqdn") // dns-records-reconciler reconcile the headless Service
wantHosts = map[string][]string{"baz.bar.ts.net": {"10.9.8.7"}}
expectHostsRecords(t, fc, wantHosts)
// 3. DNS record is updated if the IP address of the proxy Pod changes.
ep = endpointSliceForService(headlessForEgressSvcFQDN, "10.6.5.4")
mustUpdate(t, fc, ep.Namespace, ep.Name, func(ep *discoveryv1.EndpointSlice) {
ep.Endpoints[0].Addresses = []string{"10.6.5.4"}
})
expectReconciled(t, dnsRR, "tailscale", "egress-fqdn") // dns-records-reconciler reconcile the headless Service
wantHosts = map[string][]string{"baz.bar.ts.net": {"10.6.5.4"}}
expectHostsRecords(t, fc, wantHosts)
// 4. DNS record is created for an ingress proxy configured via Ingress
headlessForIngress := headlessSvcForParent(ing, "ingress")
ep = endpointSliceForService(headlessForIngress, "10.9.8.7")
mustCreate(t, fc, headlessForIngress)
mustCreate(t, fc, ep)
expectReconciled(t, dnsRR, "tailscale", "ts-ingress") // dns-records-reconciler should reconcile the headless Service
wantHosts["cluster.ingress.ts.net"] = []string{"10.9.8.7"}
expectHostsRecords(t, fc, wantHosts)
// 5. DNS records are updated if Ingress's MagicDNS name changes (i.e users changed spec.tls.hosts[0])
t.Log("test case 5")
mustUpdateStatus(t, fc, "test", "ts-ingress", func(ing *networkingv1.Ingress) {
ing.Status.LoadBalancer.Ingress[0].Hostname = "another.ingress.ts.net"
})
expectReconciled(t, dnsRR, "tailscale", "ts-ingress") // dns-records-reconciler should reconcile the headless Service
delete(wantHosts, "cluster.ingress.ts.net")
wantHosts["another.ingress.ts.net"] = []string{"10.9.8.7"}
expectHostsRecords(t, fc, wantHosts)
// 6. DNS records are updated if Ingress proxy's Pod IP changes
mustUpdate(t, fc, ep.Namespace, ep.Name, func(ep *discoveryv1.EndpointSlice) {
ep.Endpoints[0].Addresses = []string{"7.8.9.10"}
})
expectReconciled(t, dnsRR, "tailscale", "ts-ingress")
wantHosts["another.ingress.ts.net"] = []string{"7.8.9.10"}
expectHostsRecords(t, fc, wantHosts)
}
func headlessSvcForParent(o client.Object, typ string) *corev1.Service {
return &corev1.Service{
ObjectMeta: metav1.ObjectMeta{
Name: o.GetName(),
Namespace: "tailscale",
Labels: map[string]string{
LabelManaged: "true",
LabelParentName: o.GetName(),
LabelParentNamespace: o.GetNamespace(),
LabelParentType: typ,
},
},
Spec: corev1.ServiceSpec{
ClusterIP: "None",
Type: corev1.ServiceTypeClusterIP,
Selector: map[string]string{"foo": "bar"},
},
}
}
func endpointSliceForService(svc *corev1.Service, ip string) *discoveryv1.EndpointSlice {
return &discoveryv1.EndpointSlice{
ObjectMeta: metav1.ObjectMeta{
Name: svc.Name,
Namespace: svc.Namespace,
Labels: map[string]string{discoveryv1.LabelServiceName: svc.Name},
},
Endpoints: []discoveryv1.Endpoint{{
Addresses: []string{ip},
}},
}
}
func expectHostsRecords(t *testing.T, cl client.Client, wantsHosts map[string][]string) {
t.Helper()
cm := new(corev1.ConfigMap)
if err := cl.Get(context.Background(), types.NamespacedName{Name: "dnsrecords", Namespace: "tailscale"}, cm); err != nil {
t.Fatalf("getting dnsconfig ConfigMap: %v", err)
}
if cm.Data == nil {
t.Fatal("dnsconfig ConfigMap has no data")
}
dnsConfigString, ok := cm.Data[operatorutils.DNSRecordsCMKey]
if !ok {
t.Fatal("dnsconfig ConfigMap does not contain dnsconfig")
}
dnsConfig := &operatorutils.Records{}
if err := json.Unmarshal([]byte(dnsConfigString), dnsConfig); err != nil {
t.Fatalf("unmarshaling dnsconfig: %v", err)
}
if diff := cmp.Diff(dnsConfig.IP4, wantsHosts); diff != "" {
t.Fatalf("unexpected dns config (-got +want):\n%s", diff)
}
}

View File

@ -105,14 +105,14 @@ func TestNameserverReconciler(t *testing.T) {
if err != nil {
t.Fatalf("error marshalling ConfigMap contents: %v", err)
}
mustUpdate(t, fc, "tailscale", "dnsconfig", func(cm *corev1.ConfigMap) {
mak.Set(&cm.Data, "dns.json", string(bs))
mustUpdate(t, fc, "tailscale", "dnsrecords", func(cm *corev1.ConfigMap) {
mak.Set(&cm.Data, "records.json", string(bs))
})
expectReconciled(t, nr, "", "test")
wantCm := &corev1.ConfigMap{ObjectMeta: metav1.ObjectMeta{Name: "dnsconfig",
wantCm := &corev1.ConfigMap{ObjectMeta: metav1.ObjectMeta{Name: "dnsrecords",
Namespace: "tailscale", Labels: labels, OwnerReferences: []metav1.OwnerReference{*dnsCfgOwnerRef}},
TypeMeta: metav1.TypeMeta{Kind: "ConfigMap", APIVersion: "v1"},
Data: map[string]string{"dns.json": string(bs)},
Data: map[string]string{"records.json": string(bs)},
}
expectEqual(t, fc, wantCm, nil)
}

View File

@ -20,6 +20,7 @@ import (
"golang.org/x/oauth2/clientcredentials"
appsv1 "k8s.io/api/apps/v1"
corev1 "k8s.io/api/core/v1"
discoveryv1 "k8s.io/api/discovery/v1"
networkingv1 "k8s.io/api/networking/v1"
"k8s.io/apimachinery/pkg/types"
"k8s.io/client-go/rest"
@ -223,11 +224,12 @@ func runReconcilers(zlog *zap.SugaredLogger, s *tsnet.Server, tsNamespace string
// resources that we GET via the controller manager's client.
Cache: cache.Options{
ByObject: map[client.Object]cache.ByObject{
&corev1.Secret{}: nsFilter,
&corev1.ServiceAccount{}: nsFilter,
&corev1.ConfigMap{}: nsFilter,
&appsv1.StatefulSet{}: nsFilter,
&appsv1.Deployment{}: nsFilter,
&corev1.Secret{}: nsFilter,
&corev1.ServiceAccount{}: nsFilter,
&corev1.ConfigMap{}: nsFilter,
&appsv1.StatefulSet{}: nsFilter,
&appsv1.Deployment{}: nsFilter,
&discoveryv1.EndpointSlice{}: nsFilter,
},
},
Scheme: tsapi.GlobalScheme,
@ -239,7 +241,7 @@ func runReconcilers(zlog *zap.SugaredLogger, s *tsnet.Server, tsNamespace string
svcFilter := handler.EnqueueRequestsFromMapFunc(serviceHandler)
svcChildFilter := handler.EnqueueRequestsFromMapFunc(managedResourceHandlerForType("svc"))
// If a ProxyClassChanges, enqueue all Services labeled with that
// If a ProxyClass changes, enqueue all Services labeled with that
// ProxyClass's name.
proxyClassFilterForSvc := handler.EnqueueRequestsFromMapFunc(proxyClassHandlerForSvc(mgr.GetClient(), startlog))
@ -345,12 +347,128 @@ func runReconcilers(zlog *zap.SugaredLogger, s *tsnet.Server, tsNamespace string
if err != nil {
startlog.Fatal("could not create proxyclass reconciler: %v", err)
}
logger := startlog.Named("dns-records-reconciler-event-handlers")
// On EndpointSlice events, if it is an EndpointSlice for an
// ingress/egress proxy headless Service, reconcile the headless
// Service.
dnsRREpsOpts := handler.EnqueueRequestsFromMapFunc(dnsRecordsReconcilerEndpointSliceHandler)
// On DNSConfig changes, reconcile all headless Services for
// ingress/egress proxies in operator namespace.
dnsRRDNSConfigOpts := handler.EnqueueRequestsFromMapFunc(enqueueAllIngressEgressProxySvcsInNS(tsNamespace, mgr.GetClient(), logger))
// On Service events, if it is an ingress/egress proxy headless Service, reconcile it.
dnsRRServiceOpts := handler.EnqueueRequestsFromMapFunc(dnsRecordsReconcilerServiceHandler)
// On Ingress events, if it is a tailscale Ingress or if tailscale is the default ingress controller, reconcile the proxy
// headless Service.
dnsRRIngressOpts := handler.EnqueueRequestsFromMapFunc(dnsRecordsReconcilerIngressHandler(tsNamespace, isDefaultLoadBalancer, mgr.GetClient(), logger))
err = builder.ControllerManagedBy(mgr).
Named("dns-records-reconciler").
Watches(&corev1.Service{}, dnsRRServiceOpts).
Watches(&networkingv1.Ingress{}, dnsRRIngressOpts).
Watches(&discoveryv1.EndpointSlice{}, dnsRREpsOpts).
Watches(&tsapi.DNSConfig{}, dnsRRDNSConfigOpts).
Complete(&dnsRecordsReconciler{
Client: mgr.GetClient(),
tsNamespace: tsNamespace,
logger: zlog.Named("dns-records-reconciler"),
isDefaultLoadBalancer: isDefaultLoadBalancer,
})
if err != nil {
startlog.Fatalf("could not create DNS records reconciler: %v", err)
}
startlog.Infof("Startup complete, operator running, version: %s", version.Long())
if err := mgr.Start(signals.SetupSignalHandler()); err != nil {
startlog.Fatalf("could not start manager: %v", err)
}
}
// enqueueAllIngressEgressProxySvcsinNS returns a reconcile request for each
// ingress/egress proxy headless Service found in the provided namespace.
func enqueueAllIngressEgressProxySvcsInNS(ns string, cl client.Client, logger *zap.SugaredLogger) handler.MapFunc {
return func(ctx context.Context, _ client.Object) []reconcile.Request {
reqs := make([]reconcile.Request, 0)
// Get all headless Services for proxies configured using Service.
svcProxyLabels := map[string]string{
LabelManaged: "true",
LabelParentType: "svc",
}
svcHeadlessSvcList := &corev1.ServiceList{}
if err := cl.List(ctx, svcHeadlessSvcList, client.InNamespace(ns), client.MatchingLabels(svcProxyLabels)); err != nil {
logger.Errorf("error listing headless Services for tailscale ingress/egress Services in operator namespace: %v", err)
return nil
}
for _, svc := range svcHeadlessSvcList.Items {
reqs = append(reqs, reconcile.Request{NamespacedName: types.NamespacedName{Namespace: svc.Namespace, Name: svc.Name}})
}
// Get all headless Services for proxies configured using Ingress.
ingProxyLabels := map[string]string{
LabelManaged: "true",
LabelParentType: "ingress",
}
ingHeadlessSvcList := &corev1.ServiceList{}
if err := cl.List(ctx, ingHeadlessSvcList, client.InNamespace(ns), client.MatchingLabels(ingProxyLabels)); err != nil {
logger.Errorf("error listing headless Services for tailscale Ingresses in operator namespace: %v", err)
return nil
}
for _, svc := range ingHeadlessSvcList.Items {
reqs = append(reqs, reconcile.Request{NamespacedName: types.NamespacedName{Namespace: svc.Namespace, Name: svc.Name}})
}
return reqs
}
}
// dnsRecordsReconciler filters EndpointSlice events for which
// dns-records-reconciler should reconcile a headless Service. The only events
// it should reconcile are those for EndpointSlices associated with proxy
// headless Services.
func dnsRecordsReconcilerEndpointSliceHandler(ctx context.Context, o client.Object) []reconcile.Request {
if !isManagedByType(o, "svc") && !isManagedByType(o, "ingress") {
return nil
}
headlessSvcName, ok := o.GetLabels()[discoveryv1.LabelServiceName] // https://kubernetes.io/docs/concepts/services-networking/endpoint-slices/#ownership
if !ok {
return nil
}
return []reconcile.Request{{NamespacedName: types.NamespacedName{Namespace: o.GetNamespace(), Name: headlessSvcName}}}
}
// dnsRecordsReconcilerServiceHandler filters Service events for which
// dns-records-reconciler should reconcile. If the event is for a cluster
// ingress/cluster egress proxy's headless Service, returns the Service for
// reconcile.
func dnsRecordsReconcilerServiceHandler(ctx context.Context, o client.Object) []reconcile.Request {
if isManagedByType(o, "svc") || isManagedByType(o, "ingress") {
return []reconcile.Request{{NamespacedName: types.NamespacedName{Namespace: o.GetNamespace(), Name: o.GetName()}}}
}
return nil
}
// dnsRecordsReconcilerIngressHandler filters Ingress events to ensure that
// dns-records-reconciler only reconciles on tailscale Ingress events. When an
// event is observed on a tailscale Ingress, reconcile the proxy headless Service.
func dnsRecordsReconcilerIngressHandler(ns string, isDefaultLoadBalancer bool, cl client.Client, logger *zap.SugaredLogger) handler.MapFunc {
return func(ctx context.Context, o client.Object) []reconcile.Request {
ing, ok := o.(*networkingv1.Ingress)
if !ok {
return nil
}
if !isDefaultLoadBalancer && (ing.Spec.IngressClassName == nil || *ing.Spec.IngressClassName != "tailscale") {
return nil
}
proxyResourceLabels := childResourceLabels(ing.Name, ing.Namespace, "ingress")
headlessSvc, err := getSingleObject[corev1.Service](ctx, cl, ns, proxyResourceLabels)
if err != nil {
logger.Errorf("error getting headless Service from parent labels: %v", err)
return nil
}
if headlessSvc == nil {
return nil
}
return []reconcile.Request{{NamespacedName: types.NamespacedName{Namespace: headlessSvc.Namespace, Name: headlessSvc.Name}}}
}
}
type tsClient interface {
CreateKey(ctx context.Context, caps tailscale.KeyCapabilities) (string, *tailscale.Key, error)
DeleteDevice(ctx context.Context, nodeStableID string) error

View File

@ -82,7 +82,7 @@ func (a *ServiceReconciler) Reconcile(ctx context.Context, req reconcile.Request
} else if err != nil {
return reconcile.Result{}, fmt.Errorf("failed to get svc: %w", err)
}
targetIP := a.tailnetTargetAnnotation(svc)
targetIP := tailnetTargetAnnotation(svc)
targetFQDN := svc.Annotations[AnnotationTailnetTargetFQDN]
if !svc.DeletionTimestamp.IsZero() || !a.shouldExpose(svc) && targetIP == "" && targetFQDN == "" {
logger.Debugf("service is being deleted or is (no longer) referring to Tailscale ingress/egress, ensuring any created resources are cleaned up")
@ -204,7 +204,7 @@ func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.Suga
sts.ClusterTargetIP = svc.Spec.ClusterIP
a.managedIngressProxies.Add(svc.UID)
gaugeIngressProxies.Set(int64(a.managedIngressProxies.Len()))
} else if ip := a.tailnetTargetAnnotation(svc); ip != "" {
} else if ip := tailnetTargetAnnotation(svc); ip != "" {
sts.TailnetTargetIP = ip
a.managedEgressProxies.Add(svc.UID)
gaugeEgressProxies.Set(int64(a.managedEgressProxies.Len()))
@ -240,7 +240,7 @@ func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.Suga
return nil
}
if !a.hasLoadBalancerClass(svc) {
if !isTailscaleLoadBalancerService(svc, a.isDefaultLoadBalancer) {
logger.Debugf("service is not a LoadBalancer, so not updating ingress")
return nil
}
@ -303,19 +303,19 @@ func (a *ServiceReconciler) shouldExpose(svc *corev1.Service) bool {
return false
}
return a.hasLoadBalancerClass(svc) || a.hasExposeAnnotation(svc)
return isTailscaleLoadBalancerService(svc, a.isDefaultLoadBalancer) || hasExposeAnnotation(svc)
}
func (a *ServiceReconciler) hasLoadBalancerClass(svc *corev1.Service) bool {
func isTailscaleLoadBalancerService(svc *corev1.Service, isDefaultLoadBalancer bool) bool {
return svc != nil &&
svc.Spec.Type == corev1.ServiceTypeLoadBalancer &&
(svc.Spec.LoadBalancerClass != nil && *svc.Spec.LoadBalancerClass == "tailscale" ||
svc.Spec.LoadBalancerClass == nil && a.isDefaultLoadBalancer)
svc.Spec.LoadBalancerClass == nil && isDefaultLoadBalancer)
}
// hasExposeAnnotation reports whether Service has the tailscale.com/expose
// annotation set
func (a *ServiceReconciler) hasExposeAnnotation(svc *corev1.Service) bool {
func hasExposeAnnotation(svc *corev1.Service) bool {
return svc != nil && svc.Annotations[AnnotationExpose] == "true"
}
@ -323,7 +323,7 @@ func (a *ServiceReconciler) hasExposeAnnotation(svc *corev1.Service) bool {
// annotation or of the deprecated tailscale.com/ts-tailnet-target-ip
// annotation. If neither is set, it returns an empty string. If both are set,
// it returns the value of the new annotation.
func (a *ServiceReconciler) tailnetTargetAnnotation(svc *corev1.Service) string {
func tailnetTargetAnnotation(svc *corev1.Service) string {
if svc == nil {
return ""
}

2
go.mod
View File

@ -372,7 +372,7 @@ require (
k8s.io/component-base v0.29.1 // indirect
k8s.io/klog/v2 v2.120.1 // indirect
k8s.io/kube-openapi v0.0.0-20240117194847-208609032b15 // indirect
k8s.io/utils v0.0.0-20240102154912-e7106e64919e // indirect
k8s.io/utils v0.0.0-20240102154912-e7106e64919e
mvdan.cc/gofumpt v0.5.0 // indirect
mvdan.cc/interfacer v0.0.0-20180901003855-c20040233aed // indirect
mvdan.cc/lint v0.0.0-20170908181259-adc824a0674b // indirect

View File

@ -5,12 +5,18 @@
package kube
const Alpha1Version = "v1alpha1"
const (
Alpha1Version = "v1alpha1"
DNSRecordsCMName = "dnsrecords"
DNSRecordsCMKey = "records.json"
)
type Records struct {
// Version is the version of this Records configuration. Version is
// intended to be used by ./cmd/k8s-nameserver to determine whether it
// can read this records configuration.
// written by the operator, i.e when it first populates the Records.
// k8s-nameserver must verify that it knows how to parse a given
// version.
Version string `json:"version"`
// IP4 contains a mapping of DNS names to IPv4 address(es).
IP4 map[string][]string `json:"ip4"`