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Merged
openshift-merge-bot merged 6 commits into from
Jul 21, 2026
Merged

NE-2743: Support centralized TLS security profiles for CDO metrics #482

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a91d2ca
NE-2743: Vendor openshift/api and bump dependencies
Thealisyed Jul 10, 2026
4c34182
NE-2743: Align static operator deployment ciphers with Intermediate T…
Thealisyed Jul 10, 2026
669cf57
NE-2743: Sync CRD manifests with vendored openshift/api
Thealisyed Jul 10, 2026
d060e74
NE-2743: Replace kube-rbac-proxy with direct TLS serving for operator…
Thealisyed Jul 14, 2026
98f0b49
NE-2743: Log warning for unsupported TLS groups instead of silently s…
Thealisyed Jul 16, 2026
d4368ad
Address Davide's review feedback
Thealisyed Jul 17, 2026
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54 changes: 48 additions & 6 deletions cmd/dns-operator/main.go
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Original file line number Diff line number Diff line change
@@ -1,26 +1,33 @@
package main

import (
"context"
"crypto/tls"
"flag"
"os"

configv1 "github.com/openshift/api/config/v1"
configclient "github.com/openshift/client-go/config/clientset/versioned"
operatorcontroller "github.com/openshift/cluster-dns-operator/pkg/operator/controller"

"github.com/openshift/cluster-dns-operator/pkg/operator"
operatorconfig "github.com/openshift/cluster-dns-operator/pkg/operator/config"
statuscontroller "github.com/openshift/cluster-dns-operator/pkg/operator/controller/status"

"github.com/sirupsen/logrus"

metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
ctrl "sigs.k8s.io/controller-runtime"
"sigs.k8s.io/controller-runtime/pkg/client/config"
"sigs.k8s.io/controller-runtime/pkg/log/zap"
"sigs.k8s.io/controller-runtime/pkg/manager/signals"
metricsserver "sigs.k8s.io/controller-runtime/pkg/metrics/server"
)

const operatorNamespace = "openshift-dns-operator"

func main() {
metricsserver.DefaultBindAddress = "127.0.0.1:60000"
metricsBindAddr := flag.String("metrics-bind-addr", "127.0.0.1:60000", "The TCP address for the metrics endpoint.")
metricsCertDir := flag.String("metrics-cert-dir", "", "The directory containing tls.crt and tls.key for the metrics endpoint.")

opts := zap.Options{
Development: true,
Expand Down Expand Up @@ -49,18 +56,53 @@ func main() {
logrus.Fatalf("KUBE_RBAC_PROXY_IMAGE environment variable is required")
}

kubeConfig, err := config.GetConfig()
if err != nil {
logrus.Fatalf("failed to get kube config: %v", err)
}

// Build TLS options for the operator metrics server from the
// cluster-wide TLS security profile when secure serving is enabled.
// NOTE: the TLS profile is read once at startup; runtime changes to

@bentito bentito Jul 20, 2026

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While this static loading behavior is historically common in controller-runtime operators, it does introduce a subtle asymmetry in our design:

  1. When the cluster TLS profile changes, the operator's reconciler dynamically updates the CoreDNS DaemonSet (operand), immediately rolling it out to match the new profile.
  2. The operator itself, however, remains non-compliant on port 9393 until a manual restart or node reschedule occurs.

Across the OpenShift ecosystem, we have a standardized pattern to solve this exact dynamic update limitation. Instead of attempting to hot-reload TLS parameters (which can lead to inconsistent states on long-lived connections), operators use a SecurityProfileWatcher from the openshift/controller-runtime-common library to trigger a graceful self-shutdown when the TLS profile changes. Because the operator's Deployment has restartPolicy: Always, Kubernetes instantly spawns a new pod, which re-reads the fresh TLS config on boot.

You can see an example of this in the ptp-operator main.go.

This is definitely a separate, well-defined enhancement that doesn't need to block this PR. Let's merge this work as-is to unblock the kube-rbac-proxy removal, and we can track implementing the SecurityProfileWatcher in a follow-up Jira story. What do you think?

I think we should add a Jira to track this and do this as a follow-up PR.

// APIServer.spec.tlsSecurityProfile require an operator restart.
var metricsTLSOpts []func(*tls.Config)
if *metricsCertDir != "" {
cfgClient, err := configclient.NewForConfig(kubeConfig)
if err != nil {
logrus.Fatalf("failed to create config client: %v", err)
}
apiServer, err := cfgClient.ConfigV1().APIServers().Get(context.TODO(), "cluster", metav1.GetOptions{})
var tlsSecurityProfile *configv1.TLSSecurityProfile
Comment thread
Thealisyed marked this conversation as resolved.
if err != nil {
logrus.Warningf("failed to get apiserver config, using Intermediate TLS profile: %v", err)
} else {
tlsSecurityProfile = apiServer.Spec.TLSSecurityProfile
}
profileSpec := operatorcontroller.TLSProfileSpecForSecurityProfile(tlsSecurityProfile)
tlsCfg, err := operatorcontroller.TLSConfigFromProfile(profileSpec)
if err != nil {
logrus.Fatalf("failed to build TLS config from profile: %v", err)
}
metricsTLSOpts = append(metricsTLSOpts, func(cfg *tls.Config) {
cfg.CipherSuites = tlsCfg.CipherSuites
cfg.MinVersion = tlsCfg.MinVersion
if len(tlsCfg.CurvePreferences) > 0 {
cfg.CurvePreferences = tlsCfg.CurvePreferences
}
})
}

operatorConfig := operatorconfig.Config{
OperatorNamespace: operatorNamespace,
OperatorReleaseVersion: releaseVersion,
CoreDNSImage: coreDNSImage,
OpenshiftCLIImage: cliImage,
KubeRBACProxyImage: kubeRBACProxyImage,
MetricsBindAddress: *metricsBindAddr,
MetricsCertDir: *metricsCertDir,
MetricsTLSOpts: metricsTLSOpts,
}

kubeConfig, err := config.GetConfig()
if err != nil {
logrus.Fatalf("failed to get kube config %v", err)
}
ctx := signals.SetupSignalHandler()
// Set up and start the operator.
op, err := operator.New(ctx, operatorConfig, kubeConfig)
Expand Down
43 changes: 32 additions & 11 deletions go.mod
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -6,40 +6,47 @@ require (
github.com/apparentlymart/go-cidr v1.1.0
github.com/go-logr/logr v1.4.3
github.com/google/go-cmp v0.7.0
github.com/openshift/api v0.0.0-20251111193948-50e2ece149d7
github.com/openshift/api v0.0.0-20260615110019-261e3a0546f3
github.com/openshift/build-machinery-go v0.0.0-20250530140348-dc5b2804eeee
github.com/openshift/client-go v0.0.0-20251015124057-db0dee36e235
github.com/openshift/client-go v0.0.0-20260317180604-743f664b82d1
github.com/openshift/coredns-ocp-dnsnameresolver/operator v0.0.0-20260211095308-1a5277b4db1c
github.com/openshift/library-go v0.0.0-20251119174848-88c26bf0df68
github.com/sirupsen/logrus v1.9.3
github.com/stretchr/testify v1.11.1
k8s.io/api v0.35.0
k8s.io/apimachinery v0.35.0
k8s.io/client-go v0.35.0
k8s.io/kubectl v0.35.0
k8s.io/api v0.35.1
k8s.io/apimachinery v0.35.1
k8s.io/client-go v0.35.1
k8s.io/kubectl v0.35.1
k8s.io/utils v0.0.0-20251002143259-bc988d571ff4
sigs.k8s.io/controller-runtime v0.23.1
)

require (
cel.dev/expr v0.24.0 // indirect
github.com/antlr4-go/antlr/v4 v4.13.0 // indirect
github.com/beorn7/perks v1.0.1 // indirect
github.com/blang/semver/v4 v4.0.0 // indirect
github.com/cenkalti/backoff/v4 v4.3.0 // indirect
github.com/cespare/xxhash/v2 v2.3.0 // indirect
github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
github.com/emicklei/go-restful/v3 v3.12.2 // indirect
github.com/evanphx/json-patch v5.6.0+incompatible // indirect
github.com/evanphx/json-patch/v5 v5.9.11 // indirect
github.com/felixge/httpsnoop v1.0.4 // indirect
github.com/fsnotify/fsnotify v1.9.0 // indirect
github.com/fxamacker/cbor/v2 v2.9.0 // indirect
github.com/go-logr/stdr v1.2.2 // indirect
github.com/go-logr/zapr v1.3.0 // indirect
github.com/go-openapi/jsonpointer v0.21.0 // indirect
github.com/go-openapi/jsonreference v0.20.2 // indirect
github.com/go-openapi/swag v0.23.0 // indirect
github.com/gogo/protobuf v1.3.2 // indirect
github.com/google/btree v1.1.3 // indirect
github.com/google/cel-go v0.26.0 // indirect
github.com/google/gnostic-models v0.7.0 // indirect
github.com/google/uuid v1.6.0 // indirect
github.com/grpc-ecosystem/grpc-gateway/v2 v2.26.3 // indirect
github.com/imdario/mergo v0.3.12 // indirect
github.com/inconshreveable/mousetrap v1.1.0 // indirect
github.com/josharian/intern v1.0.0 // indirect
github.com/json-iterator/go v1.1.12 // indirect
github.com/mailru/easyjson v0.7.7 // indirect
Expand All @@ -53,14 +60,24 @@ require (
github.com/prometheus/common v0.66.1 // indirect
github.com/prometheus/procfs v0.16.1 // indirect
github.com/robfig/cron v1.2.0 // indirect
github.com/spf13/cobra v1.10.0 // indirect
github.com/spf13/pflag v1.0.9 // indirect
github.com/stoewer/go-strcase v1.3.0 // indirect
github.com/x448/float16 v0.8.4 // indirect
go.opentelemetry.io/auto/sdk v1.1.0 // indirect
go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.61.0 // indirect
go.opentelemetry.io/otel v1.36.0 // indirect
go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.34.0 // indirect
go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.34.0 // indirect
go.opentelemetry.io/otel/metric v1.36.0 // indirect
go.opentelemetry.io/otel/sdk v1.36.0 // indirect
go.opentelemetry.io/otel/trace v1.36.0 // indirect
go.opentelemetry.io/proto/otlp v1.5.0 // indirect
go.uber.org/multierr v1.11.0 // indirect
go.uber.org/zap v1.27.0 // indirect
go.yaml.in/yaml/v2 v2.4.3 // indirect
go.yaml.in/yaml/v3 v3.0.4 // indirect
golang.org/x/exp v0.0.0-20240719175910-8a7402abbf56 // indirect
golang.org/x/mod v0.29.0 // indirect
golang.org/x/net v0.47.0 // indirect
golang.org/x/oauth2 v0.30.0 // indirect
Expand All @@ -71,16 +88,20 @@ require (
golang.org/x/time v0.9.0 // indirect
golang.org/x/tools v0.38.0 // indirect
gomodules.xyz/jsonpatch/v2 v2.4.0 // indirect
google.golang.org/genproto/googleapis/api v0.0.0-20250303144028-a0af3efb3deb // indirect
google.golang.org/genproto/googleapis/rpc v0.0.0-20250528174236-200df99c418a // indirect
google.golang.org/grpc v1.72.2 // indirect
google.golang.org/protobuf v1.36.8 // indirect
gopkg.in/evanphx/json-patch.v4 v4.13.0 // indirect
gopkg.in/inf.v0 v0.9.1 // indirect
gopkg.in/yaml.v3 v3.0.1 // indirect
k8s.io/apiextensions-apiserver v0.35.0 // indirect
k8s.io/apiserver v0.35.0 // indirect
k8s.io/component-base v0.35.0 // indirect
k8s.io/apiextensions-apiserver v0.35.1 // indirect
k8s.io/apiserver v0.35.1 // indirect
k8s.io/component-base v0.35.1 // indirect
k8s.io/klog/v2 v2.130.1 // indirect
k8s.io/kube-aggregator v0.35.0 // indirect
k8s.io/kube-aggregator v0.35.1 // indirect
k8s.io/kube-openapi v0.0.0-20250910181357-589584f1c912 // indirect
sigs.k8s.io/apiserver-network-proxy/konnectivity-client v0.31.2 // indirect
sigs.k8s.io/json v0.0.0-20250730193827-2d320260d730 // indirect
sigs.k8s.io/kube-storage-version-migrator v0.0.6-0.20230721195810-5c8923c5ff96 // indirect
sigs.k8s.io/randfill v1.0.0 // indirect
Expand Down
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