constellation/bootstrapper/internal/kubernetes/k8sapi/util.go

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/*
Copyright (c) Edgeless Systems GmbH
SPDX-License-Identifier: AGPL-3.0-only
*/
package k8sapi
import (
"context"
"crypto/rand"
"crypto/x509"
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"encoding/json"
"encoding/pem"
"errors"
"fmt"
"io/fs"
"net"
"net/http"
"os"
"os/exec"
"path/filepath"
"strconv"
"strings"
"time"
"github.com/edgelesssys/constellation/bootstrapper/internal/kubelet"
"github.com/edgelesssys/constellation/bootstrapper/internal/kubernetes/k8sapi/resources"
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"github.com/edgelesssys/constellation/internal/constants"
"github.com/edgelesssys/constellation/internal/kubernetes"
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kubeconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
"github.com/edgelesssys/constellation/internal/crypto"
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"github.com/edgelesssys/constellation/internal/deploy/helm"
"github.com/edgelesssys/constellation/internal/file"
"github.com/edgelesssys/constellation/internal/logger"
"github.com/edgelesssys/constellation/internal/versions"
"github.com/icholy/replace"
"github.com/spf13/afero"
"go.uber.org/zap"
"golang.org/x/text/transform"
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"helm.sh/helm/v3/pkg/action"
"helm.sh/helm/v3/pkg/cli"
corev1 "k8s.io/api/core/v1"
)
const (
// kubeConfig is the path to the Kubernetes admin config (used for authentication).
kubeConfig = "/etc/kubernetes/admin.conf"
// kubeletStartTimeout is the maximum time given to the kubelet service to (re)start.
kubeletStartTimeout = 10 * time.Minute
// crdTimeout is the maximum time given to the CRDs to be created.
crdTimeout = 15 * time.Second
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// helmTimeout is the maximum time given to the helm client.
helmTimeout = 5 * time.Minute
)
// Client provides the functions to talk to the k8s API.
type Client interface {
Apply(resources kubernetes.Marshaler, forceConflicts bool) error
SetKubeconfig(kubeconfig []byte)
CreateConfigMap(ctx context.Context, configMap corev1.ConfigMap) error
AddTolerationsToDeployment(ctx context.Context, tolerations []corev1.Toleration, name string, namespace string) error
AddNodeSelectorsToDeployment(ctx context.Context, selectors map[string]string, name string, namespace string) error
WaitForCRDs(ctx context.Context, crds []string) error
}
type installer interface {
Install(
ctx context.Context, sourceURL string, destinations []string, perm fs.FileMode,
extract bool, transforms ...transform.Transformer,
) error
}
// KubernetesUtil provides low level management of the kubernetes cluster.
type KubernetesUtil struct {
inst installer
file file.Handler
}
// NewKubernetesUtil creates a new KubernetesUtil.
func NewKubernetesUtil() *KubernetesUtil {
return &KubernetesUtil{
inst: newOSInstaller(),
file: file.NewHandler(afero.NewOsFs()),
}
}
// InstallComponents installs kubernetes components in the version specified.
func (k *KubernetesUtil) InstallComponents(ctx context.Context, version versions.ValidK8sVersion) error {
versionConf := versions.VersionConfigs[version]
if err := k.inst.Install(
ctx, versionConf.CNIPluginsURL, []string{cniPluginsDir}, executablePerm, true,
); err != nil {
return fmt.Errorf("installing cni plugins: %w", err)
}
if err := k.inst.Install(
ctx, versionConf.CrictlURL, []string{binDir}, executablePerm, true,
); err != nil {
return fmt.Errorf("installing crictl: %w", err)
}
if err := k.inst.Install(
ctx, versionConf.KubeletServiceURL, []string{kubeletServiceEtcPath, kubeletServiceStatePath}, systemdUnitPerm, false, replace.String("/usr/bin", binDir),
); err != nil {
return fmt.Errorf("installing kubelet service: %w", err)
}
if err := k.inst.Install(
ctx, versionConf.KubeadmConfURL, []string{kubeadmConfEtcPath, kubeadmConfStatePath}, systemdUnitPerm, false, replace.String("/usr/bin", binDir),
); err != nil {
return fmt.Errorf("installing kubeadm conf: %w", err)
}
if err := k.inst.Install(
ctx, versionConf.KubeletURL, []string{kubeletPath}, executablePerm, false,
); err != nil {
return fmt.Errorf("installing kubelet: %w", err)
}
if err := k.inst.Install(
ctx, versionConf.KubeadmURL, []string{kubeadmPath}, executablePerm, false,
); err != nil {
return fmt.Errorf("installing kubeadm: %w", err)
}
if err := k.inst.Install(
ctx, versionConf.KubectlURL, []string{kubectlPath}, executablePerm, false,
); err != nil {
return fmt.Errorf("installing kubectl: %w", err)
}
return enableSystemdUnit(ctx, kubeletServiceEtcPath)
}
func (k *KubernetesUtil) InitCluster(
ctx context.Context, initConfig []byte, nodeName string, ips []net.IP, log *logger.Logger,
) error {
// TODO: audit policy should be user input
auditPolicy, err := resources.NewDefaultAuditPolicy().Marshal()
if err != nil {
return fmt.Errorf("generating default audit policy: %w", err)
}
if err := os.WriteFile(auditPolicyPath, auditPolicy, 0o644); err != nil {
return fmt.Errorf("writing default audit policy: %w", err)
}
initConfigFile, err := os.CreateTemp("", "kubeadm-init.*.yaml")
if err != nil {
return fmt.Errorf("creating init config file %v: %w", initConfigFile.Name(), err)
}
if _, err := initConfigFile.Write(initConfig); err != nil {
return fmt.Errorf("writing kubeadm init yaml config %v: %w", initConfigFile.Name(), err)
}
// preflight
log.Infof("Running kubeadm preflight checks")
cmd := exec.CommandContext(ctx, kubeadmPath, "init", "phase", "preflight", "-v=5", "--config", initConfigFile.Name())
out, err := cmd.CombinedOutput()
if err != nil {
var exitErr *exec.ExitError
if errors.As(err, &exitErr) {
return fmt.Errorf("kubeadm init phase preflight failed (code %v) with: %s", exitErr.ExitCode(), out)
}
return fmt.Errorf("kubeadm init: %w", err)
}
// create CA certs
log.Infof("Creating Kubernetes control-plane certificates and keys")
cmd = exec.CommandContext(ctx, kubeadmPath, "init", "phase", "certs", "all", "-v=5", "--config", initConfigFile.Name())
out, err = cmd.CombinedOutput()
if err != nil {
var exitErr *exec.ExitError
if errors.As(err, &exitErr) {
return fmt.Errorf("kubeadm init phase certs all failed (code %v) with: %s", exitErr.ExitCode(), out)
}
return fmt.Errorf("kubeadm init: %w", err)
}
// create kubelet key and CA signed certificate for the node
log.Infof("Creating signed kubelet certificate")
if err := k.createSignedKubeletCert(nodeName, ips); err != nil {
return err
}
// initialize the cluster
log.Infof("Initializing the cluster using kubeadm init")
cmd = exec.CommandContext(ctx, kubeadmPath, "init", "-v=5", "--skip-phases=preflight,certs,addon/kube-proxy", "--config", initConfigFile.Name())
out, err = cmd.CombinedOutput()
if err != nil {
var exitErr *exec.ExitError
if errors.As(err, &exitErr) {
return fmt.Errorf("kubeadm init failed (code %v) with: %s", exitErr.ExitCode(), out)
}
return fmt.Errorf("kubeadm init: %w", err)
}
log.With(zap.String("output", string(out))).Infof("kubeadm init succeeded")
return nil
}
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func (k *KubernetesUtil) SetupHelmDeployments(ctx context.Context, kubectl Client, helmDeployments []byte, in SetupPodNetworkInput, log *logger.Logger) error {
var helmDeploy helm.Deployments
if err := json.Unmarshal(helmDeployments, &helmDeploy); err != nil {
return fmt.Errorf("unmarshalling helm deployments: %w", err)
}
settings := cli.New()
settings.KubeConfig = kubeConfig
actionConfig := new(action.Configuration)
if err := actionConfig.Init(settings.RESTClientGetter(), constants.HelmNamespace,
"secret", log.Infof); err != nil {
return err
}
helmClient := action.NewInstall(actionConfig)
helmClient.Namespace = constants.HelmNamespace
helmClient.ReleaseName = "cilium"
helmClient.Wait = true
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helmClient.Timeout = helmTimeout
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if err := k.deployCilium(ctx, in, helmClient, helmDeploy.Cilium, kubectl); err != nil {
return fmt.Errorf("deploying cilium: %w", err)
}
return nil
}
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type SetupPodNetworkInput struct {
CloudProvider string
NodeName string
FirstNodePodCIDR string
SubnetworkPodCIDR string
ProviderID string
LoadBalancerEndpoint string
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}
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// deployCilium sets up the cilium pod network.
func (k *KubernetesUtil) deployCilium(ctx context.Context, in SetupPodNetworkInput, helmClient *action.Install, ciliumDeployment helm.Deployment, kubectl Client) error {
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switch in.CloudProvider {
case "gcp":
return k.deployCiliumGCP(ctx, helmClient, kubectl, ciliumDeployment, in.NodeName, in.FirstNodePodCIDR, in.SubnetworkPodCIDR, in.LoadBalancerEndpoint)
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case "azure":
return k.deployCiliumAzure(ctx, helmClient, ciliumDeployment, in.LoadBalancerEndpoint)
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case "qemu":
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return k.deployCiliumQEMU(ctx, helmClient, ciliumDeployment, in.SubnetworkPodCIDR, in.LoadBalancerEndpoint)
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default:
return fmt.Errorf("unsupported cloud provider %q", in.CloudProvider)
}
}
func (k *KubernetesUtil) deployCiliumAzure(ctx context.Context, helmClient *action.Install, ciliumDeployment helm.Deployment, kubeAPIEndpoint string) error {
host := kubeAPIEndpoint
ciliumDeployment.Values["k8sServiceHost"] = host
ciliumDeployment.Values["k8sServicePort"] = strconv.Itoa(constants.KubernetesPort)
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_, err := helmClient.RunWithContext(ctx, ciliumDeployment.Chart, ciliumDeployment.Values)
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if err != nil {
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return fmt.Errorf("installing cilium: %w", err)
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}
return nil
}
func (k *KubernetesUtil) deployCiliumGCP(ctx context.Context, helmClient *action.Install, kubectl Client, ciliumDeployment helm.Deployment, nodeName, nodePodCIDR, subnetworkPodCIDR, kubeAPIEndpoint string) error {
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out, err := exec.CommandContext(ctx, kubectlPath, "--kubeconfig", kubeConfig, "patch", "node", nodeName, "-p", "{\"spec\":{\"podCIDR\": \""+nodePodCIDR+"\"}}").CombinedOutput()
if err != nil {
err = errors.New(string(out))
return err
}
timeoutS := int64(10)
// allow coredns to run on uninitialized nodes (required by cloud-controller-manager)
tolerations := []corev1.Toleration{
{
Key: "node.cloudprovider.kubernetes.io/uninitialized",
Value: "true",
Effect: corev1.TaintEffectNoSchedule,
},
{
Key: "node.kubernetes.io/unreachable",
Operator: corev1.TolerationOpExists,
Effect: corev1.TaintEffectNoExecute,
TolerationSeconds: &timeoutS,
},
}
if err = kubectl.AddTolerationsToDeployment(ctx, tolerations, "coredns", "kube-system"); err != nil {
return err
}
selectors := map[string]string{
"node-role.kubernetes.io/control-plane": "",
}
if err = kubectl.AddNodeSelectorsToDeployment(ctx, selectors, "coredns", "kube-system"); err != nil {
return err
}
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host, port, err := net.SplitHostPort(kubeAPIEndpoint)
if err != nil {
return err
}
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// configure pod network CIDR
ciliumDeployment.Values["ipv4NativeRoutingCIDR"] = subnetworkPodCIDR
ciliumDeployment.Values["strictModeCIDR"] = subnetworkPodCIDR
ciliumDeployment.Values["k8sServiceHost"] = host
if port != "" {
ciliumDeployment.Values["k8sServicePort"] = port
}
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_, err = helmClient.RunWithContext(ctx, ciliumDeployment.Chart, ciliumDeployment.Values)
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if err != nil {
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return fmt.Errorf("installing cilium: %w", err)
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}
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return nil
}
// FixCilium fixes https://github.com/cilium/cilium/issues/19958 but instead of a rollout restart of
// the cilium daemonset, it only restarts the local cilium pod.
func (k *KubernetesUtil) FixCilium(log *logger.Logger) {
// wait for cilium pod to be healthy
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client := http.Client{}
for {
time.Sleep(5 * time.Second)
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req, err := http.NewRequestWithContext(context.Background(), http.MethodGet, "http://127.0.0.1:9879/healthz", http.NoBody)
if err != nil {
log.With(zap.Error(err)).Errorf("Unable to create request")
continue
}
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resp, err := client.Do(req)
if err != nil {
log.With(zap.Error(err)).Warnf("Waiting for local cilium daemonset pod not healthy")
continue
}
resp.Body.Close()
if resp.StatusCode == 200 {
break
}
}
// get cilium pod name
out, err := exec.CommandContext(context.Background(), "/bin/bash", "-c", "/run/state/bin/crictl ps -o json | jq -r '.containers[] | select(.metadata.name == \"cilium-agent\") | .podSandboxId'").CombinedOutput()
if err != nil {
log.With(zap.Error(err)).Errorf("Getting pod id failed: %s", out)
return
}
outLines := strings.Split(string(out), "\n")
podID := outLines[len(outLines)-2]
// stop and delete pod
out, err = exec.CommandContext(context.Background(), "/run/state/bin/crictl", "stopp", podID).CombinedOutput()
if err != nil {
log.With(zap.Error(err)).Errorf("Stopping cilium agent pod failed: %s", out)
return
}
out, err = exec.CommandContext(context.Background(), "/run/state/bin/crictl", "rmp", podID).CombinedOutput()
if err != nil {
log.With(zap.Error(err)).Errorf("Removing cilium agent pod failed: %s", out)
}
}
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func (k *KubernetesUtil) deployCiliumQEMU(ctx context.Context, helmClient *action.Install, ciliumDeployment helm.Deployment, subnetworkPodCIDR, kubeAPIEndpoint string) error {
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// configure pod network CIDR
ciliumDeployment.Values["ipam"] = map[string]interface{}{
"operator": map[string]interface{}{
"clusterPoolIPv4PodCIDRList": []interface{}{
subnetworkPodCIDR,
},
},
}
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ciliumDeployment.Values["k8sServiceHost"] = kubeAPIEndpoint
ciliumDeployment.Values["k8sServicePort"] = strconv.Itoa(constants.KubernetesPort)
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_, err := helmClient.RunWithContext(ctx, ciliumDeployment.Chart, ciliumDeployment.Values)
if err != nil {
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return fmt.Errorf("installing cilium: %w", err)
}
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return nil
}
// SetupAutoscaling deploys the k8s cluster autoscaler.
func (k *KubernetesUtil) SetupAutoscaling(kubectl Client, clusterAutoscalerConfiguration kubernetes.Marshaler, secrets kubernetes.Marshaler) error {
if err := kubectl.Apply(secrets, true); err != nil {
return fmt.Errorf("applying cluster-autoscaler Secrets: %w", err)
}
return kubectl.Apply(clusterAutoscalerConfiguration, true)
}
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// SetupJoinService deploys the Constellation node join service.
func (k *KubernetesUtil) SetupJoinService(kubectl Client, joinServiceConfiguration kubernetes.Marshaler) error {
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return kubectl.Apply(joinServiceConfiguration, true)
}
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// SetupGCPGuestAgent deploys the GCP guest agent daemon set.
func (k *KubernetesUtil) SetupGCPGuestAgent(kubectl Client, guestAgentDaemonset kubernetes.Marshaler) error {
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return kubectl.Apply(guestAgentDaemonset, true)
}
// SetupCloudControllerManager deploys the k8s cloud-controller-manager.
func (k *KubernetesUtil) SetupCloudControllerManager(kubectl Client, cloudControllerManagerConfiguration kubernetes.Marshaler, configMaps kubernetes.Marshaler, secrets kubernetes.Marshaler) error {
if err := kubectl.Apply(configMaps, true); err != nil {
return fmt.Errorf("applying ccm ConfigMaps: %w", err)
}
if err := kubectl.Apply(secrets, true); err != nil {
return fmt.Errorf("applying ccm Secrets: %w", err)
}
if err := kubectl.Apply(cloudControllerManagerConfiguration, true); err != nil {
return fmt.Errorf("applying ccm: %w", err)
}
return nil
}
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// SetupCloudNodeManager deploys the k8s cloud-node-manager.
func (k *KubernetesUtil) SetupCloudNodeManager(kubectl Client, cloudNodeManagerConfiguration kubernetes.Marshaler) error {
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return kubectl.Apply(cloudNodeManagerConfiguration, true)
}
// SetupAccessManager deploys the constellation-access-manager for deploying SSH keys on control-plane & worker nodes.
func (k *KubernetesUtil) SetupAccessManager(kubectl Client, accessManagerConfiguration kubernetes.Marshaler) error {
return kubectl.Apply(accessManagerConfiguration, true)
}
// SetupKMS deploys the KMS deployment.
func (k *KubernetesUtil) SetupKMS(kubectl Client, kmsConfiguration kubernetes.Marshaler) error {
if err := kubectl.Apply(kmsConfiguration, true); err != nil {
return fmt.Errorf("applying KMS configuration: %w", err)
}
return nil
}
// SetupVerificationService deploys the verification service.
func (k *KubernetesUtil) SetupVerificationService(kubectl Client, verificationServiceConfiguration kubernetes.Marshaler) error {
return kubectl.Apply(verificationServiceConfiguration, true)
}
func (k *KubernetesUtil) SetupOperatorLifecycleManager(ctx context.Context, kubectl Client, olmCRDs, olmConfiguration kubernetes.Marshaler, crdNames []string) error {
if err := kubectl.Apply(olmCRDs, true); err != nil {
return fmt.Errorf("applying OLM CRDs: %w", err)
}
crdReadyTimeout, cancel := context.WithTimeout(ctx, crdTimeout)
defer cancel()
if err := kubectl.WaitForCRDs(crdReadyTimeout, crdNames); err != nil {
return fmt.Errorf("waiting for OLM CRDs: %w", err)
}
return kubectl.Apply(olmConfiguration, true)
}
func (k *KubernetesUtil) SetupNodeMaintenanceOperator(kubectl Client, nodeMaintenanceOperatorConfiguration kubernetes.Marshaler) error {
return kubectl.Apply(nodeMaintenanceOperatorConfiguration, true)
}
func (k *KubernetesUtil) SetupNodeOperator(ctx context.Context, kubectl Client, nodeOperatorConfiguration kubernetes.Marshaler) error {
return kubectl.Apply(nodeOperatorConfiguration, true)
}
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// JoinCluster joins existing Kubernetes cluster using kubeadm join.
func (k *KubernetesUtil) JoinCluster(ctx context.Context, joinConfig []byte, log *logger.Logger) error {
// TODO: audit policy should be user input
auditPolicy, err := resources.NewDefaultAuditPolicy().Marshal()
if err != nil {
return fmt.Errorf("generating default audit policy: %w", err)
}
if err := os.WriteFile(auditPolicyPath, auditPolicy, 0o644); err != nil {
return fmt.Errorf("writing default audit policy: %w", err)
}
joinConfigFile, err := os.CreateTemp("", "kubeadm-join.*.yaml")
if err != nil {
return fmt.Errorf("creating join config file %v: %w", joinConfigFile.Name(), err)
}
if _, err := joinConfigFile.Write(joinConfig); err != nil {
return fmt.Errorf("writing kubeadm init yaml config %v: %w", joinConfigFile.Name(), err)
}
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// run `kubeadm join` to join a worker node to an existing Kubernetes cluster
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cmd := exec.CommandContext(ctx, kubeadmPath, "join", "-v=5", "--config", joinConfigFile.Name())
out, err := cmd.CombinedOutput()
if err != nil {
var exitErr *exec.ExitError
if errors.As(err, &exitErr) {
return fmt.Errorf("kubeadm join failed (code %v) with: %s (full err: %s)", exitErr.ExitCode(), out, err)
}
return fmt.Errorf("kubeadm join: %w", err)
}
log.With(zap.String("output", string(out))).Infof("kubeadm join succeeded")
return nil
}
// StartKubelet enables and starts the kubelet systemd unit.
func (k *KubernetesUtil) StartKubelet() error {
ctx, cancel := context.WithTimeout(context.TODO(), kubeletStartTimeout)
defer cancel()
if err := enableSystemdUnit(ctx, kubeletServiceEtcPath); err != nil {
return fmt.Errorf("enabling kubelet systemd unit: %w", err)
}
return startSystemdUnit(ctx, "kubelet.service")
}
// createSignedKubeletCert manually creates a Kubernetes CA signed kubelet certificate for the bootstrapper node.
// This is necessary because this node does not request a certificate from the join service.
func (k *KubernetesUtil) createSignedKubeletCert(nodeName string, ips []net.IP) error {
certRequestRaw, kubeletKey, err := kubelet.GetCertificateRequest(nodeName, ips)
if err != nil {
return err
}
if err := k.file.Write(kubelet.KeyFilename, kubeletKey, file.OptMkdirAll); err != nil {
return err
}
parentCertRaw, err := k.file.Read(filepath.Join(
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kubeconstants.KubernetesDir,
kubeconstants.DefaultCertificateDir,
kubeconstants.CACertName,
))
if err != nil {
return err
}
parentCert, err := crypto.PemToX509Cert(parentCertRaw)
if err != nil {
return err
}
parentKeyRaw, err := k.file.Read(filepath.Join(
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kubeconstants.KubernetesDir,
kubeconstants.DefaultCertificateDir,
kubeconstants.CAKeyName,
))
if err != nil {
return err
}
parentKeyPEM, _ := pem.Decode(parentKeyRaw)
var parentKey any
switch parentKeyPEM.Type {
case "EC PRIVATE KEY":
parentKey, err = x509.ParseECPrivateKey(parentKeyPEM.Bytes)
case "RSA PRIVATE KEY":
parentKey, err = x509.ParsePKCS1PrivateKey(parentKeyPEM.Bytes)
case "PRIVATE KEY":
parentKey, err = x509.ParsePKCS8PrivateKey(parentKeyPEM.Bytes)
default:
err = fmt.Errorf("unsupported key type %q", parentKeyPEM.Type)
}
if err != nil {
return err
}
certRequest, err := x509.ParseCertificateRequest(certRequestRaw)
if err != nil {
return err
}
serialNumber, err := crypto.GenerateCertificateSerialNumber()
if err != nil {
return err
}
now := time.Now()
// Create the kubelet certificate
// For a reference on the certificate fields, see: https://kubernetes.io/docs/setup/best-practices/certificates/
certTmpl := &x509.Certificate{
SerialNumber: serialNumber,
NotBefore: now.Add(-2 * time.Hour),
NotAfter: now.Add(24 * 365 * time.Hour),
Subject: certRequest.Subject,
KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{
x509.ExtKeyUsageClientAuth,
x509.ExtKeyUsageServerAuth,
},
IsCA: false,
BasicConstraintsValid: true,
IPAddresses: certRequest.IPAddresses,
}
certRaw, err := x509.CreateCertificate(rand.Reader, certTmpl, parentCert, certRequest.PublicKey, parentKey)
if err != nil {
return err
}
kubeletCert := pem.EncodeToMemory(&pem.Block{
Type: "CERTIFICATE",
Bytes: certRaw,
})
return k.file.Write(kubelet.CertificateFilename, kubeletCert, file.OptMkdirAll)
}