From 82734c256a6a00bd653090e835980110dfc85d20 Mon Sep 17 00:00:00 2001 From: Monis Khan Date: Fri, 25 Jun 2021 22:08:10 -0400 Subject: [PATCH] csr: add expirationSeconds field to control cert lifetime This change updates the CSR API to add a new, optional field called expirationSeconds. This field is a request to the signer for the maximum duration the client wishes the cert to have. The signer is free to ignore this request based on its own internal policy. The signers built-in to KCM will honor this field if it is not set to a value greater than --cluster-signing-duration. The minimum allowed value for this field is 600 seconds (ten minutes). This change will help enforce safer durations for certificates in the Kube ecosystem and will help related projects such as cert-manager with their migration to the Kube CSR API. Future enhancements may update the Kubelet to take advantage of this field when it is configured in a way that can tolerate shorter certificate lifespans with regular rotation. Signed-off-by: Monis Khan Kubernetes-commit: cd91e59f7c351fce47c064a5162c2cb79075159c --- pkg/describe/describe.go | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/pkg/describe/describe.go b/pkg/describe/describe.go index 35d137052..b366c0441 100644 --- a/pkg/describe/describe.go +++ b/pkg/describe/describe.go @@ -33,7 +33,6 @@ import ( "unicode" "github.com/fatih/camelcase" - "k8s.io/apimachinery/pkg/runtime" appsv1 "k8s.io/api/apps/v1" autoscalingv1 "k8s.io/api/autoscaling/v1" @@ -60,6 +59,7 @@ import ( metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apimachinery/pkg/fields" "k8s.io/apimachinery/pkg/labels" + "k8s.io/apimachinery/pkg/runtime" "k8s.io/apimachinery/pkg/runtime/schema" "k8s.io/apimachinery/pkg/types" "k8s.io/apimachinery/pkg/util/duration" @@ -72,6 +72,7 @@ import ( corev1client "k8s.io/client-go/kubernetes/typed/core/v1" "k8s.io/client-go/rest" "k8s.io/client-go/tools/reference" + utilcsr "k8s.io/client-go/util/certificate/csr" "k8s.io/klog/v2" "k8s.io/kubectl/pkg/scheme" "k8s.io/kubectl/pkg/util/certificate" @@ -3690,12 +3691,13 @@ type CertificateSigningRequestDescriber struct { func (p *CertificateSigningRequestDescriber) Describe(namespace, name string, describerSettings DescriberSettings) (string, error) { var ( - crBytes []byte - metadata metav1.ObjectMeta - status string - signerName string - username string - events *corev1.EventList + crBytes []byte + metadata metav1.ObjectMeta + status string + signerName string + expirationSeconds *int32 + username string + events *corev1.EventList ) if csr, err := p.client.CertificatesV1().CertificateSigningRequests().Get(context.TODO(), name, metav1.GetOptions{}); err == nil { @@ -3707,6 +3709,7 @@ func (p *CertificateSigningRequestDescriber) Describe(namespace, name string, de } status = extractCSRStatus(conditionTypes, csr.Status.Certificate) signerName = csr.Spec.SignerName + expirationSeconds = csr.Spec.ExpirationSeconds username = csr.Spec.Username if describerSettings.ShowEvents { events, _ = searchEvents(p.client.CoreV1(), csr, describerSettings.ChunkSize) @@ -3722,6 +3725,7 @@ func (p *CertificateSigningRequestDescriber) Describe(namespace, name string, de if csr.Spec.SignerName != nil { signerName = *csr.Spec.SignerName } + expirationSeconds = csr.Spec.ExpirationSeconds username = csr.Spec.Username if describerSettings.ShowEvents { events, _ = searchEvents(p.client.CoreV1(), csr, describerSettings.ChunkSize) @@ -3735,10 +3739,10 @@ func (p *CertificateSigningRequestDescriber) Describe(namespace, name string, de return "", fmt.Errorf("Error parsing CSR: %v", err) } - return describeCertificateSigningRequest(metadata, signerName, username, cr, status, events) + return describeCertificateSigningRequest(metadata, signerName, expirationSeconds, username, cr, status, events) } -func describeCertificateSigningRequest(csr metav1.ObjectMeta, signerName string, username string, cr *x509.CertificateRequest, status string, events *corev1.EventList) (string, error) { +func describeCertificateSigningRequest(csr metav1.ObjectMeta, signerName string, expirationSeconds *int32, username string, cr *x509.CertificateRequest, status string, events *corev1.EventList) (string, error) { printListHelper := func(w PrefixWriter, prefix, name string, values []string) { if len(values) == 0 { return @@ -3758,6 +3762,9 @@ func describeCertificateSigningRequest(csr metav1.ObjectMeta, signerName string, if len(signerName) > 0 { w.Write(LEVEL_0, "Signer:\t%s\n", signerName) } + if expirationSeconds != nil { + w.Write(LEVEL_0, "Requested Duration:\t%s\n", duration.HumanDuration(utilcsr.ExpirationSecondsToDuration(*expirationSeconds))) + } w.Write(LEVEL_0, "Status:\t%s\n", status) w.Write(LEVEL_0, "Subject:\n")