diff --git a/cmd/containerboot/main.go b/cmd/containerboot/main.go index df1b3c3fb..56bbd2874 100644 --- a/cmd/containerboot/main.go +++ b/cmd/containerboot/main.go @@ -17,7 +17,9 @@ // - TS_DEST_IP: proxy all incoming Tailscale traffic to the given // destination. // - TS_TAILNET_TARGET_IP: proxy all incoming non-Tailscale traffic to the given -// destination. +// destination defined by an IP. +// - TS_TAILNET_TARGET_FQDN: proxy all incoming non-Tailscale traffic to the given +// destination defined by a MagicDNS name. // - TS_TAILSCALED_EXTRA_ARGS: extra arguments to 'tailscaled'. // - TS_EXTRA_ARGS: extra arguments to 'tailscale up'. // - TS_USERSPACE: run with userspace networking (the default) @@ -78,6 +80,7 @@ import ( "golang.org/x/sys/unix" "tailscale.com/client/tailscale" "tailscale.com/ipn" + "tailscale.com/tailcfg" "tailscale.com/types/logger" "tailscale.com/types/ptr" "tailscale.com/util/deephash" @@ -96,24 +99,25 @@ func main() { tailscale.I_Acknowledge_This_API_Is_Unstable = true cfg := &settings{ - AuthKey: defaultEnvs([]string{"TS_AUTHKEY", "TS_AUTH_KEY"}, ""), - Hostname: defaultEnv("TS_HOSTNAME", ""), - Routes: defaultEnv("TS_ROUTES", ""), - ServeConfigPath: defaultEnv("TS_SERVE_CONFIG", ""), - ProxyTo: defaultEnv("TS_DEST_IP", ""), - TailnetTargetIP: defaultEnv("TS_TAILNET_TARGET_IP", ""), - DaemonExtraArgs: defaultEnv("TS_TAILSCALED_EXTRA_ARGS", ""), - ExtraArgs: defaultEnv("TS_EXTRA_ARGS", ""), - InKubernetes: os.Getenv("KUBERNETES_SERVICE_HOST") != "", - UserspaceMode: defaultBool("TS_USERSPACE", true), - StateDir: defaultEnv("TS_STATE_DIR", ""), - AcceptDNS: defaultBool("TS_ACCEPT_DNS", false), - KubeSecret: defaultEnv("TS_KUBE_SECRET", "tailscale"), - SOCKSProxyAddr: defaultEnv("TS_SOCKS5_SERVER", ""), - HTTPProxyAddr: defaultEnv("TS_OUTBOUND_HTTP_PROXY_LISTEN", ""), - Socket: defaultEnv("TS_SOCKET", "/tmp/tailscaled.sock"), - AuthOnce: defaultBool("TS_AUTH_ONCE", false), - Root: defaultEnv("TS_TEST_ONLY_ROOT", "/"), + AuthKey: defaultEnvs([]string{"TS_AUTHKEY", "TS_AUTH_KEY"}, ""), + Hostname: defaultEnv("TS_HOSTNAME", ""), + Routes: defaultEnv("TS_ROUTES", ""), + ServeConfigPath: defaultEnv("TS_SERVE_CONFIG", ""), + ProxyTo: defaultEnv("TS_DEST_IP", ""), + TailnetTargetIP: defaultEnv("TS_TAILNET_TARGET_IP", ""), + TailnetTargetFQDN: defaultEnv("TS_TAILNET_TARGET_FQDN", ""), + DaemonExtraArgs: defaultEnv("TS_TAILSCALED_EXTRA_ARGS", ""), + ExtraArgs: defaultEnv("TS_EXTRA_ARGS", ""), + InKubernetes: os.Getenv("KUBERNETES_SERVICE_HOST") != "", + UserspaceMode: defaultBool("TS_USERSPACE", true), + StateDir: defaultEnv("TS_STATE_DIR", ""), + AcceptDNS: defaultBool("TS_ACCEPT_DNS", false), + KubeSecret: defaultEnv("TS_KUBE_SECRET", "tailscale"), + SOCKSProxyAddr: defaultEnv("TS_SOCKS5_SERVER", ""), + HTTPProxyAddr: defaultEnv("TS_OUTBOUND_HTTP_PROXY_LISTEN", ""), + Socket: defaultEnv("TS_SOCKET", "/tmp/tailscaled.sock"), + AuthOnce: defaultBool("TS_AUTH_ONCE", false), + Root: defaultEnv("TS_TEST_ONLY_ROOT", "/"), } if cfg.ProxyTo != "" && cfg.UserspaceMode { @@ -123,13 +127,19 @@ func main() { if cfg.TailnetTargetIP != "" && cfg.UserspaceMode { log.Fatal("TS_TAILNET_TARGET_IP is not supported with TS_USERSPACE") } + if cfg.TailnetTargetFQDN != "" && cfg.UserspaceMode { + log.Fatal("TS_TAILNET_TARGET_FQDN is not supported with TS_USERSPACE") + } + if cfg.TailnetTargetFQDN != "" && cfg.TailnetTargetIP != "" { + log.Fatal("Both TS_TAILNET_TARGET_IP and TS_TAILNET_FQDN cannot be set") + } if !cfg.UserspaceMode { if err := ensureTunFile(cfg.Root); err != nil { log.Fatalf("Unable to create tuntap device file: %v", err) } - if cfg.ProxyTo != "" || cfg.Routes != "" || cfg.TailnetTargetIP != "" { - if err := ensureIPForwarding(cfg.Root, cfg.ProxyTo, cfg.TailnetTargetIP, cfg.Routes); err != nil { + if cfg.ProxyTo != "" || cfg.Routes != "" || cfg.TailnetTargetIP != "" || cfg.TailnetTargetFQDN != "" { + if err := ensureIPForwarding(cfg.Root, cfg.ProxyTo, cfg.TailnetTargetIP, cfg.TailnetTargetFQDN, cfg.Routes); err != nil { log.Printf("Failed to enable IP forwarding: %v", err) log.Printf("To run tailscale as a proxy or router container, IP forwarding must be enabled.") if cfg.InKubernetes { @@ -294,12 +304,14 @@ authLoop: } var ( - wantProxy = cfg.ProxyTo != "" || cfg.TailnetTargetIP != "" + wantProxy = cfg.ProxyTo != "" || cfg.TailnetTargetIP != "" || cfg.TailnetTargetFQDN != "" wantDeviceInfo = cfg.InKubernetes && cfg.KubeSecret != "" && cfg.KubernetesCanPatch startupTasksDone = false currentIPs deephash.Sum // tailscale IPs assigned to device currentDeviceInfo deephash.Sum // device ID and fqdn + currentEgressIPs deephash.Sum + certDomain = new(atomic.Pointer[string]) certDomainChanged = make(chan bool, 1) ) @@ -352,6 +364,45 @@ runLoop: addrs := n.NetMap.SelfNode.Addresses().AsSlice() newCurrentIPs := deephash.Hash(&addrs) ipsHaveChanged := newCurrentIPs != currentIPs + + if cfg.TailnetTargetFQDN != "" { + var ( + egressAddrs []netip.Prefix + newCurentEgressIPs deephash.Sum + egressIPsHaveChanged bool + node tailcfg.NodeView + nodeFound bool + ) + for _, n := range n.NetMap.Peers { + if strings.EqualFold(n.Name(), cfg.TailnetTargetFQDN) { + node = n + nodeFound = true + break + } + } + if !nodeFound { + log.Printf("Tailscale node %q not found; it either does not exist, or not reachable because of ACLs", cfg.TailnetTargetFQDN) + break + } + egressAddrs = node.Addresses().AsSlice() + newCurentEgressIPs = deephash.Hash(&egressAddrs) + egressIPsHaveChanged = newCurentEgressIPs != currentEgressIPs + if egressIPsHaveChanged && len(egressAddrs) > 0 { + for _, egressAddr := range egressAddrs { + ea := egressAddr.Addr() + // TODO (irbekrm): make it work for IPv6 too. + if ea.Is6() { + log.Println("Not installing egress forwarding rules for IPv6 as this is currently not supported") + continue + } + log.Printf("Installing forwarding rules for destination %v", ea.String()) + if err := installEgressForwardingRule(ctx, ea.String(), addrs, nfr); err != nil { + log.Fatalf("installing egress proxy rules for destination %s: %v", ea.String(), err) + } + } + } + currentEgressIPs = newCurentEgressIPs + } if cfg.ProxyTo != "" && len(addrs) > 0 && ipsHaveChanged { log.Printf("Installing proxy rules") if err := installIngressForwardingRule(ctx, cfg.ProxyTo, addrs, nfr); err != nil { @@ -369,6 +420,7 @@ runLoop: } } if cfg.TailnetTargetIP != "" && ipsHaveChanged && len(addrs) > 0 { + log.Printf("Installing forwarding rules for destination %v", cfg.TailnetTargetIP) if err := installEgressForwardingRule(ctx, cfg.TailnetTargetIP, addrs, nfr); err != nil { log.Fatalf("installing egress proxy rules: %v", err) } @@ -389,10 +441,10 @@ runLoop: log.Println("Startup complete, waiting for shutdown signal") startupTasksDone = true - // // Reap all processes, since we are PID1 and need to collect zombies. We can - // // only start doing this once we've stopped shelling out to things - // // `tailscale up`, otherwise this goroutine can reap the CLI subprocesses - // // and wedge bringup. + // Reap all processes, since we are PID1 and need to collect zombies. We can + // only start doing this once we've stopped shelling out to things + // `tailscale up`, otherwise this goroutine can reap the CLI subprocesses + // and wedge bringup. reaper := func() { defer wg.Done() for { @@ -644,7 +696,7 @@ func ensureTunFile(root string) error { } // ensureIPForwarding enables IPv4/IPv6 forwarding for the container. -func ensureIPForwarding(root, clusterProxyTarget, tailnetTargetiP, routes string) error { +func ensureIPForwarding(root, clusterProxyTarget, tailnetTargetiP, tailnetTargetFQDN, routes string) error { var ( v4Forwarding, v6Forwarding bool ) @@ -670,6 +722,11 @@ func ensureIPForwarding(root, clusterProxyTarget, tailnetTargetiP, routes string v6Forwarding = true } } + // Currently we only proxy traffic to the IPv4 address of the tailnet + // target. + if tailnetTargetFQDN != "" { + v4Forwarding = true + } if routes != "" { for _, route := range strings.Split(routes, ",") { cidr, err := netip.ParsePrefix(route) @@ -781,9 +838,13 @@ type settings struct { // is done. This is typically a locally reachable IP. ProxyTo string // TailnetTargetIP is the destination IP to which all incoming - // non-Tailscale traffic should be proxied. If empty, no - // proxying is done. This is typically a Tailscale IP. - TailnetTargetIP string + // non-Tailscale traffic should be proxied. This is typically a + // Tailscale IP. + TailnetTargetIP string + // TailnetTargetFQDN is an MagicDNS name to which all incoming + // non-Tailscale traffic should be proxied. This must be a full Tailnet + // node FQDN. + TailnetTargetFQDN string ServeConfigPath string DaemonExtraArgs string ExtraArgs string diff --git a/cmd/k8s-operator/operator.go b/cmd/k8s-operator/operator.go index 79d70778a..49af08a47 100644 --- a/cmd/k8s-operator/operator.go +++ b/cmd/k8s-operator/operator.go @@ -10,6 +10,7 @@ package main import ( "context" "os" + "regexp" "strings" "time" @@ -322,3 +323,10 @@ func serviceHandler(_ context.Context, o client.Object) []reconcile.Request { } } + +// isMagicDNSName reports whether name is a full tailnet node FQDN (with or +// without final dot). +func isMagicDNSName(name string) bool { + validMagicDNSName := regexp.MustCompile(`^[a-zA-Z0-9-]+\.[a-zA-Z0-9-]+\.ts\.net\.?$`) + return validMagicDNSName.MatchString(name) +} diff --git a/cmd/k8s-operator/operator_test.go b/cmd/k8s-operator/operator_test.go index 985a29fa7..881f8c959 100644 --- a/cmd/k8s-operator/operator_test.go +++ b/cmd/k8s-operator/operator_test.go @@ -159,6 +159,119 @@ func TestLoadBalancerClass(t *testing.T) { } expectEqual(t, fc, want) } +func TestTailnetTargetFQDNAnnotation(t *testing.T) { + fc := fake.NewFakeClient() + ft := &fakeTSClient{} + zl, err := zap.NewDevelopment() + if err != nil { + t.Fatal(err) + } + tailnetTargetFQDN := "foo.bar.ts.net." + sr := &ServiceReconciler{ + Client: fc, + ssr: &tailscaleSTSReconciler{ + Client: fc, + tsClient: ft, + defaultTags: []string{"tag:k8s"}, + operatorNamespace: "operator-ns", + proxyImage: "tailscale/tailscale", + }, + logger: zl.Sugar(), + } + + // Create a service that we should manage, and check that the initial round + // of objects looks right. + mustCreate(t, fc, &corev1.Service{ + ObjectMeta: metav1.ObjectMeta{ + Name: "test", + Namespace: "default", + // The apiserver is supposed to set the UID, but the fake client + // doesn't. So, set it explicitly because other code later depends + // on it being set. + UID: types.UID("1234-UID"), + Annotations: map[string]string{ + AnnotationTailnetTargetFQDN: tailnetTargetFQDN, + }, + }, + Spec: corev1.ServiceSpec{ + Type: corev1.ServiceTypeClusterIP, + Selector: map[string]string{ + "foo": "bar", + }, + }, + }) + + expectReconciled(t, sr, "default", "test") + + fullName, shortName := findGenName(t, fc, "default", "test") + + expectEqual(t, fc, expectedSecret(fullName)) + expectEqual(t, fc, expectedHeadlessService(shortName)) + o := stsOpts{ + name: shortName, + secretName: fullName, + tailnetTargetFQDN: tailnetTargetFQDN, + hostname: "default-test", + } + expectEqual(t, fc, expectedSTS(o)) + want := &corev1.Service{ + TypeMeta: metav1.TypeMeta{ + Kind: "Service", + APIVersion: "v1", + }, + ObjectMeta: metav1.ObjectMeta{ + Name: "test", + Namespace: "default", + Finalizers: []string{"tailscale.com/finalizer"}, + UID: types.UID("1234-UID"), + Annotations: map[string]string{ + AnnotationTailnetTargetFQDN: tailnetTargetFQDN, + }, + }, + Spec: corev1.ServiceSpec{ + ExternalName: fmt.Sprintf("%s.operator-ns.svc.cluster.local", shortName), + Type: corev1.ServiceTypeExternalName, + Selector: nil, + }, + } + expectEqual(t, fc, want) + expectEqual(t, fc, expectedSecret(fullName)) + expectEqual(t, fc, expectedHeadlessService(shortName)) + o = stsOpts{ + name: shortName, + secretName: fullName, + tailnetTargetFQDN: tailnetTargetFQDN, + hostname: "default-test", + } + expectEqual(t, fc, expectedSTS(o)) + + // Change the tailscale-target-fqdn annotation which should update the + // StatefulSet + tailnetTargetFQDN = "bar.baz.ts.net" + mustUpdate(t, fc, "default", "test", func(s *corev1.Service) { + s.ObjectMeta.Annotations = map[string]string{ + AnnotationTailnetTargetFQDN: tailnetTargetFQDN, + } + }) + + // Remove the tailscale-target-fqdn annotation which should make the + // operator clean up + mustUpdate(t, fc, "default", "test", func(s *corev1.Service) { + s.ObjectMeta.Annotations = map[string]string{} + }) + expectReconciled(t, sr, "default", "test") + + // // synchronous StatefulSet deletion triggers a requeue. But, the StatefulSet + // // didn't create any child resources since this is all faked, so the + // // deletion goes through immediately. + expectReconciled(t, sr, "default", "test") + expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName) + // // The deletion triggers another reconcile, to finish the cleanup. + expectReconciled(t, sr, "default", "test") + expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName) + expectMissing[corev1.Service](t, fc, "operator-ns", shortName) + expectMissing[corev1.Secret](t, fc, "operator-ns", fullName) +} func TestTailnetTargetIPAnnotation(t *testing.T) { fc := fake.NewFakeClient() ft := &fakeTSClient{} @@ -271,10 +384,6 @@ func TestTailnetTargetIPAnnotation(t *testing.T) { expectMissing[appsv1.StatefulSet](t, fc, "operator-ns", shortName) expectMissing[corev1.Service](t, fc, "operator-ns", shortName) expectMissing[corev1.Secret](t, fc, "operator-ns", fullName) - - // At the moment we don't revert changes to the user created Service - - // we don't have a reliable way how to tell what it was before and also - // we don't really expect it to be re-used } func TestAnnotations(t *testing.T) { @@ -987,6 +1096,13 @@ func expectedSTS(opts stsOpts) *appsv1.StatefulSet { Name: "TS_TAILNET_TARGET_IP", Value: opts.tailnetTargetIP, }) + } else if opts.tailnetTargetFQDN != "" { + annots["tailscale.com/operator-last-set-ts-tailnet-target-fqdn"] = opts.tailnetTargetFQDN + containerEnv = append(containerEnv, corev1.EnvVar{ + Name: "TS_TAILNET_TARGET_FQDN", + Value: opts.tailnetTargetFQDN, + }) + } else { containerEnv = append(containerEnv, corev1.EnvVar{ Name: "TS_DEST_IP", @@ -1194,6 +1310,7 @@ type stsOpts struct { priorityClassName string firewallMode string tailnetTargetIP string + tailnetTargetFQDN string } type fakeTSClient struct { @@ -1232,3 +1349,30 @@ func (c *fakeTSClient) Deleted() []string { defer c.Unlock() return c.deleted } + +func Test_isMagicDNSName(t *testing.T) { + tests := []struct { + in string + want bool + }{ + { + in: "foo.tail4567.ts.net", + want: true, + }, + { + in: "foo.tail4567.ts.net.", + want: true, + }, + { + in: "foo.tail4567", + want: false, + }, + } + for _, tt := range tests { + t.Run(tt.in, func(t *testing.T) { + if got := isMagicDNSName(tt.in); got != tt.want { + t.Errorf("isMagicDNSName(%q) = %v, want %v", tt.in, got, tt.want) + } + }) + } +} diff --git a/cmd/k8s-operator/sts.go b/cmd/k8s-operator/sts.go index ee344c5dc..042490e92 100644 --- a/cmd/k8s-operator/sts.go +++ b/cmd/k8s-operator/sts.go @@ -47,15 +47,18 @@ const ( AnnotationHostname = "tailscale.com/hostname" annotationTailnetTargetIPOld = "tailscale.com/ts-tailnet-target-ip" AnnotationTailnetTargetIP = "tailscale.com/tailnet-ip" + //MagicDNS name of tailnet node. + AnnotationTailnetTargetFQDN = "tailscale.com/tailnet-fqdn" // Annotations settable by users on ingresses. AnnotationFunnel = "tailscale.com/funnel" // Annotations set by the operator on pods to trigger restarts when the - // hostname or IP changes. - podAnnotationLastSetClusterIP = "tailscale.com/operator-last-set-cluster-ip" - podAnnotationLastSetHostname = "tailscale.com/operator-last-set-hostname" - podAnnotationLastSetTailnetTargetIP = "tailscale.com/operator-last-set-ts-tailnet-target-ip" + // hostname, IP or FQDN changes. + podAnnotationLastSetClusterIP = "tailscale.com/operator-last-set-cluster-ip" + podAnnotationLastSetHostname = "tailscale.com/operator-last-set-hostname" + podAnnotationLastSetTailnetTargetIP = "tailscale.com/operator-last-set-ts-tailnet-target-ip" + podAnnotationLastSetTailnetTargetFQDN = "tailscale.com/operator-last-set-ts-tailnet-target-fqdn" ) type tailscaleSTSConfig struct { @@ -70,6 +73,9 @@ type tailscaleSTSConfig struct { // Tailscale IP of a Tailscale service we are setting up egress for TailnetTargetIP string + // Tailscale FQDN of a Tailscale service we are setting up egress for + TailnetTargetFQDN string + Hostname string Tags []string // if empty, use defaultTags } @@ -382,7 +388,11 @@ func (a *tailscaleSTSReconciler) reconcileSTS(ctx context.Context, logger *zap.S Name: "TS_TAILNET_TARGET_IP", Value: sts.TailnetTargetIP, }) - + } else if sts.TailnetTargetFQDN != "" { + container.Env = append(container.Env, corev1.EnvVar{ + Name: "TS_TAILNET_TARGET_FQDN", + Value: sts.TailnetTargetFQDN, + }) } else if sts.ServeConfig != nil { container.Env = append(container.Env, corev1.EnvVar{ Name: "TS_SERVE_CONFIG", @@ -438,6 +448,9 @@ func (a *tailscaleSTSReconciler) reconcileSTS(ctx context.Context, logger *zap.S if sts.TailnetTargetIP != "" { ss.Spec.Template.Annotations[podAnnotationLastSetTailnetTargetIP] = sts.TailnetTargetIP } + if sts.TailnetTargetFQDN != "" { + ss.Spec.Template.Annotations[podAnnotationLastSetTailnetTargetFQDN] = sts.TailnetTargetFQDN + } ss.Spec.Template.Labels = map[string]string{ "app": sts.ParentResourceUID, } diff --git a/cmd/k8s-operator/svc.go b/cmd/k8s-operator/svc.go index b927cda4f..d6b810e73 100644 --- a/cmd/k8s-operator/svc.go +++ b/cmd/k8s-operator/svc.go @@ -81,7 +81,8 @@ func (a *ServiceReconciler) Reconcile(ctx context.Context, req reconcile.Request return reconcile.Result{}, fmt.Errorf("failed to get svc: %w", err) } targetIP := a.tailnetTargetAnnotation(svc) - if !svc.DeletionTimestamp.IsZero() || !a.shouldExpose(svc) && targetIP == "" { + 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") return reconcile.Result{}, a.maybeCleanup(ctx, logger, svc) } @@ -139,15 +140,21 @@ func (a *ServiceReconciler) maybeCleanup(ctx context.Context, logger *zap.Sugare // This function adds a finalizer to svc, ensuring that we can handle orderly // deprovisioning later. func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.SugaredLogger, svc *corev1.Service) error { - // run for proxy config related validations here as opposed to running - // them earlier. This is to prevent cleanup etc being blocked on a - // misconfigured proxy param + // Run for proxy config related validations here as opposed to running + // them earlier. This is to prevent cleanup being blocked on a + // misconfigured proxy param. if err := a.ssr.validate(); err != nil { msg := fmt.Sprintf("unable to provision proxy resources: invalid config: %v", err) a.recorder.Event(svc, corev1.EventTypeWarning, "INVALIDCONFIG", msg) a.logger.Error(msg) return nil } + if violations := validateService(svc); len(violations) > 0 { + msg := fmt.Sprintf("unable to provision proxy resources: invalid Service: %s", strings.Join(violations, ", ")) + a.recorder.Event(svc, corev1.EventTypeWarning, "INVALIDSERVCICE", msg) + a.logger.Error(msg) + return nil + } hostname, err := nameForService(svc) if err != nil { return err @@ -187,6 +194,14 @@ func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.Suga sts.TailnetTargetIP = ip a.managedEgressProxies.Add(svc.UID) gaugeEgressProxies.Set(int64(a.managedEgressProxies.Len())) + } else if fqdn := svc.Annotations[AnnotationTailnetTargetFQDN]; fqdn != "" { + fqdn := svc.Annotations[AnnotationTailnetTargetFQDN] + if !strings.HasSuffix(fqdn, ".") { + fqdn = fqdn + "." + } + sts.TailnetTargetFQDN = fqdn + a.managedEgressProxies.Add(svc.UID) + gaugeEgressProxies.Set(int64(a.managedEgressProxies.Len())) } a.mu.Unlock() @@ -195,7 +210,7 @@ func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.Suga return fmt.Errorf("failed to provision: %w", err) } - if sts.TailnetTargetIP != "" { + if sts.TailnetTargetIP != "" || sts.TailnetTargetFQDN != "" { // TODO (irbekrm): cluster.local is the default DNS name, but // can be changed by users. Make this configurable or figure out // how to discover the DNS name from within operator @@ -254,6 +269,19 @@ func (a *ServiceReconciler) maybeProvision(ctx context.Context, logger *zap.Suga return nil } +func validateService(svc *corev1.Service) []string { + violations := make([]string, 0) + if svc.Annotations[AnnotationTailnetTargetFQDN] != "" && svc.Annotations[AnnotationTailnetTargetIP] != "" { + violations = append(violations, "only one of annotations %s and %s can be set", AnnotationTailnetTargetIP, AnnotationTailnetTargetFQDN) + } + if fqdn := svc.Annotations[AnnotationTailnetTargetFQDN]; fqdn != "" { + if !isMagicDNSName(fqdn) { + violations = append(violations, fmt.Sprintf("invalid value of annotation %s: %q does not appear to be a valid MagicDNS name", AnnotationTailnetTargetFQDN, fqdn)) + } + } + return violations +} + func (a *ServiceReconciler) shouldExpose(svc *corev1.Service) bool { // Headless services can't be exposed, since there is no ClusterIP to // forward to.