constellation/bootstrapper/internal/kubernetes/k8sapi/kubeadm_config.go
Leonard Cohnen cfcc0898b2 helm: remove konnectivity from control-planes
This is the first step in our migration off of
konnectivity. Before node-to-node encryption
we used konnectivity to route some KubeAPI
to kubelet traffic over the pod network which then
would be encrypted.

Since we enabled node-to-node encryption this has no
security upsides anymore. Note that we still deploy
the konnectivity agents via helm and still have the
load balancer for konnectivity.

In the following releases we will remove both.
2023-11-15 19:27:33 +01:00

305 lines
11 KiB
Go

/*
Copyright (c) Edgeless Systems GmbH
SPDX-License-Identifier: AGPL-3.0-only
*/
package k8sapi
import (
"path/filepath"
"github.com/edgelesssys/constellation/v2/bootstrapper/internal/certificate"
"github.com/edgelesssys/constellation/v2/internal/constants"
"github.com/edgelesssys/constellation/v2/internal/kubernetes"
corev1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
kubeletconf "k8s.io/kubelet/config/v1beta1"
kubeadm "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta3"
kubeconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
)
// Uses types defined here: https://kubernetes.io/docs/reference/config-api/kubeadm-config.v1beta3/
// Slimmed down to the fields we require
const (
auditLogDir = "/var/log/kubernetes/audit/"
auditLogFile = "audit.log"
auditPolicyPath = "/etc/kubernetes/audit-policy.yaml"
)
// KubdeadmConfiguration is used to generate kubeadm configurations.
type KubdeadmConfiguration struct{}
// InitConfiguration returns a new init configuration.
func (c *KubdeadmConfiguration) InitConfiguration(externalCloudProvider bool, clusterVersion string) KubeadmInitYAML {
var cloudProvider string
if externalCloudProvider {
cloudProvider = "external"
}
return KubeadmInitYAML{
InitConfiguration: kubeadm.InitConfiguration{
TypeMeta: metav1.TypeMeta{
APIVersion: kubeadm.SchemeGroupVersion.String(),
Kind: "InitConfiguration",
},
NodeRegistration: kubeadm.NodeRegistrationOptions{
CRISocket: "unix:///run/containerd/containerd.sock",
KubeletExtraArgs: map[string]string{
"cloud-provider": cloudProvider,
},
},
// AdvertiseAddress will be overwritten later
LocalAPIEndpoint: kubeadm.APIEndpoint{
BindPort: constants.KubernetesPort,
},
},
// https://pkg.go.dev/k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta3#ClusterConfiguration
ClusterConfiguration: kubeadm.ClusterConfiguration{
TypeMeta: metav1.TypeMeta{
Kind: "ClusterConfiguration",
APIVersion: kubeadm.SchemeGroupVersion.String(),
},
// Target kubernetes version of the control plane.
KubernetesVersion: clusterVersion,
// necessary to be able to access the kubeapi server through localhost
APIServer: kubeadm.APIServer{
ControlPlaneComponent: kubeadm.ControlPlaneComponent{
ExtraArgs: map[string]string{
"audit-policy-file": auditPolicyPath,
"audit-log-path": filepath.Join(auditLogDir, auditLogFile), // CIS benchmark
"audit-log-maxage": "30", // CIS benchmark - Default value of Rancher
// log size = 10 files * 100MB + 100 MB (which is currently being written) = 1.1GB
"audit-log-maxbackup": "10", // CIS benchmark - Default value of Rancher
"audit-log-maxsize": "100", // CIS benchmark - Default value of Rancher
"profiling": "false", // CIS benchmark
"kubelet-certificate-authority": filepath.Join(
kubeconstants.KubernetesDir,
kubeconstants.DefaultCertificateDir,
kubeconstants.CACertName,
),
"tls-cipher-suites": "TLS_AES_128_GCM_SHA256,TLS_AES_256_GCM_SHA384,TLS_CHACHA20_POLY1305_SHA256," +
"TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256," +
"TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384," +
"TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256," +
"TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256," +
"TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305," +
"TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,TLS_RSA_WITH_3DES_EDE_CBC_SHA,TLS_RSA_WITH_AES_128_CBC_SHA," +
"TLS_RSA_WITH_AES_128_GCM_SHA256,TLS_RSA_WITH_AES_256_CBC_SHA,TLS_RSA_WITH_AES_256_GCM_SHA384", // CIS benchmark
},
ExtraVolumes: []kubeadm.HostPathMount{
{
Name: "audit-log",
HostPath: auditLogDir,
MountPath: auditLogDir,
ReadOnly: false,
PathType: corev1.HostPathDirectoryOrCreate,
},
{
Name: "audit",
HostPath: auditPolicyPath,
MountPath: auditPolicyPath,
ReadOnly: true,
PathType: corev1.HostPathFile,
},
},
},
CertSANs: []string{"127.0.0.1"},
},
ControllerManager: kubeadm.ControlPlaneComponent{
ExtraArgs: map[string]string{
"flex-volume-plugin-dir": "/opt/libexec/kubernetes/kubelet-plugins/volume/exec/",
"cloud-provider": cloudProvider,
"configure-cloud-routes": "false",
"profiling": "false", // CIS benchmark
"terminated-pod-gc-threshold": "1000", // CIS benchmark - Default value of Rancher
},
},
Scheduler: kubeadm.ControlPlaneComponent{
ExtraArgs: map[string]string{
"profiling": "false",
},
},
},
// warning: this config is applied to every node in the cluster!
KubeletConfiguration: kubeletconf.KubeletConfiguration{
ProtectKernelDefaults: true, // CIS benchmark
TLSCipherSuites: []string{
"TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
"TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
"TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305",
"TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
"TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305",
"TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
"TLS_RSA_WITH_AES_256_GCM_SHA384",
"TLS_RSA_WITH_AES_128_GCM_SHA256",
}, // CIS benchmark
StaticPodPath: "/etc/kubernetes/manifests",
TypeMeta: metav1.TypeMeta{
APIVersion: kubeletconf.SchemeGroupVersion.String(),
Kind: "KubeletConfiguration",
},
RegisterWithTaints: []corev1.Taint{
{
Key: "node.cloudprovider.kubernetes.io/uninitialized",
Value: "true",
Effect: corev1.TaintEffectPreferNoSchedule,
},
{
Key: "node.cilium.io/agent-not-ready",
Value: "true",
Effect: corev1.TaintEffectPreferNoSchedule,
},
},
TLSCertFile: certificate.CertificateFilename,
TLSPrivateKeyFile: certificate.KeyFilename,
},
}
}
// JoinConfiguration returns a new kubeadm join configuration.
func (c *KubdeadmConfiguration) JoinConfiguration(externalCloudProvider bool) KubeadmJoinYAML {
var cloudProvider string
if externalCloudProvider {
cloudProvider = "external"
}
return KubeadmJoinYAML{
JoinConfiguration: kubeadm.JoinConfiguration{
TypeMeta: metav1.TypeMeta{
APIVersion: kubeadm.SchemeGroupVersion.String(),
Kind: "JoinConfiguration",
},
NodeRegistration: kubeadm.NodeRegistrationOptions{
CRISocket: "unix:///run/containerd/containerd.sock",
KubeletExtraArgs: map[string]string{
"cloud-provider": cloudProvider,
},
},
Discovery: kubeadm.Discovery{
BootstrapToken: &kubeadm.BootstrapTokenDiscovery{},
},
},
KubeletConfiguration: kubeletconf.KubeletConfiguration{
TypeMeta: metav1.TypeMeta{
APIVersion: kubeletconf.SchemeGroupVersion.String(),
Kind: "KubeletConfiguration",
},
},
}
}
// KubeadmJoinYAML holds configuration for kubeadm join workflow.
type KubeadmJoinYAML struct {
JoinConfiguration kubeadm.JoinConfiguration
KubeletConfiguration kubeletconf.KubeletConfiguration
}
// SetNodeName sets the node name.
func (k *KubeadmJoinYAML) SetNodeName(nodeName string) {
k.JoinConfiguration.NodeRegistration.Name = nodeName
}
// SetAPIServerEndpoint sets the api server endpoint.
func (k *KubeadmJoinYAML) SetAPIServerEndpoint(apiServerEndpoint string) {
k.JoinConfiguration.Discovery.BootstrapToken.APIServerEndpoint = apiServerEndpoint
}
// SetToken sets the boostrap token.
func (k *KubeadmJoinYAML) SetToken(token string) {
k.JoinConfiguration.Discovery.BootstrapToken.Token = token
}
// AppendDiscoveryTokenCaCertHash appends another trusted discovery token CA hash.
func (k *KubeadmJoinYAML) AppendDiscoveryTokenCaCertHash(discoveryTokenCaCertHash string) {
k.JoinConfiguration.Discovery.BootstrapToken.CACertHashes = append(k.JoinConfiguration.Discovery.BootstrapToken.CACertHashes, discoveryTokenCaCertHash)
}
// SetNodeIP sets the node IP.
func (k *KubeadmJoinYAML) SetNodeIP(nodeIP string) {
if k.JoinConfiguration.NodeRegistration.KubeletExtraArgs == nil {
k.JoinConfiguration.NodeRegistration.KubeletExtraArgs = map[string]string{"node-ip": nodeIP}
} else {
k.JoinConfiguration.NodeRegistration.KubeletExtraArgs["node-ip"] = nodeIP
}
}
// SetProviderID sets the provider ID.
func (k *KubeadmJoinYAML) SetProviderID(providerID string) {
k.KubeletConfiguration.ProviderID = providerID
}
// SetControlPlane sets the control plane with the advertised address.
func (k *KubeadmJoinYAML) SetControlPlane(advertiseAddress string) {
k.JoinConfiguration.ControlPlane = &kubeadm.JoinControlPlane{
LocalAPIEndpoint: kubeadm.APIEndpoint{
AdvertiseAddress: advertiseAddress,
BindPort: constants.KubernetesPort,
},
}
k.JoinConfiguration.SkipPhases = []string{"control-plane-prepare/download-certs"}
}
// Marshal into a k8s resource YAML.
func (k *KubeadmJoinYAML) Marshal() ([]byte, error) {
return kubernetes.MarshalK8SResources(k)
}
// KubeadmInitYAML holds configuration for kubeadm init workflow.
type KubeadmInitYAML struct {
InitConfiguration kubeadm.InitConfiguration
ClusterConfiguration kubeadm.ClusterConfiguration
KubeletConfiguration kubeletconf.KubeletConfiguration
}
// SetNodeName sets name of node.
func (k *KubeadmInitYAML) SetNodeName(nodeName string) {
k.InitConfiguration.NodeRegistration.Name = nodeName
}
// SetClusterName sets the name of the Kubernetes cluster.
// This name is reflected in the kubeconfig file and in the name of the default admin user.
func (k *KubeadmInitYAML) SetClusterName(clusterName string) {
k.ClusterConfiguration.ClusterName = clusterName
}
// SetCertSANs sets the SANs for the certificate.
func (k *KubeadmInitYAML) SetCertSANs(certSANs []string) {
for _, certSAN := range certSANs {
if certSAN == "" {
continue
}
k.ClusterConfiguration.APIServer.CertSANs = append(k.ClusterConfiguration.APIServer.CertSANs, certSAN)
}
}
// SetControlPlaneEndpoint sets the control plane endpoint if controlPlaneEndpoint is not empty.
func (k *KubeadmInitYAML) SetControlPlaneEndpoint(controlPlaneEndpoint string) {
if controlPlaneEndpoint != "" {
k.ClusterConfiguration.ControlPlaneEndpoint = controlPlaneEndpoint
}
}
// SetNodeIP sets the node IP.
func (k *KubeadmInitYAML) SetNodeIP(nodeIP string) {
if k.InitConfiguration.NodeRegistration.KubeletExtraArgs == nil {
k.InitConfiguration.NodeRegistration.KubeletExtraArgs = map[string]string{"node-ip": nodeIP}
} else {
k.InitConfiguration.NodeRegistration.KubeletExtraArgs["node-ip"] = nodeIP
}
}
// SetProviderID sets the provider ID.
func (k *KubeadmInitYAML) SetProviderID(providerID string) {
if k.InitConfiguration.NodeRegistration.KubeletExtraArgs == nil {
k.InitConfiguration.NodeRegistration.KubeletExtraArgs = map[string]string{"provider-id": providerID}
} else {
k.InitConfiguration.NodeRegistration.KubeletExtraArgs["provider-id"] = providerID
}
}
// Marshal into a k8s resource YAML.
func (k *KubeadmInitYAML) Marshal() ([]byte, error) {
return kubernetes.MarshalK8SResources(k)
}