add authentication/authorization to kubernetes-discovery

cmd/kubernetes-discovery/pkg/cmd/server/start.go

@@ -40,8 +40,10 @@ import (
 const defaultEtcdPathPrefix = "/registry/kubernetes.io/kubernetes-discovery"
 
 type DiscoveryServerOptions struct {
-	Etcd          *genericoptions.EtcdOptions
-	SecureServing *genericoptions.SecureServingOptions
+	Etcd           *genericoptions.EtcdOptions
+	SecureServing  *genericoptions.SecureServingOptions
+	Authentication *genericoptions.DelegatingAuthenticationOptions
+	Authorization  *genericoptions.DelegatingAuthorizationOptions
 
 	StdOut io.Writer
 	StdErr io.Writer
@@ -50,8 +52,10 @@ type DiscoveryServerOptions struct {
 // NewCommandStartMaster provides a CLI handler for 'start master' command
 func NewCommandStartDiscoveryServer(out, err io.Writer) *cobra.Command {
 	o := &DiscoveryServerOptions{
-		Etcd:          genericoptions.NewEtcdOptions(),
-		SecureServing: genericoptions.NewSecureServingOptions(),
+		Etcd:           genericoptions.NewEtcdOptions(),
+		SecureServing:  genericoptions.NewSecureServingOptions(),
+		Authentication: genericoptions.NewDelegatingAuthenticationOptions(),
+		Authorization:  genericoptions.NewDelegatingAuthorizationOptions(),
 
 		StdOut: out,
 		StdErr: err,
@@ -73,6 +77,8 @@ func NewCommandStartDiscoveryServer(out, err io.Writer) *cobra.Command {
 	flags := cmd.Flags()
 	o.Etcd.AddFlags(flags)
 	o.SecureServing.AddFlags(flags)
+	o.Authentication.AddFlags(flags)
+	o.Authorization.AddFlags(flags)
 
 	return cmd
 }
@@ -100,6 +106,12 @@ func (o DiscoveryServerOptions) RunDiscoveryServer() error {
 	if _, err := genericAPIServerConfig.ApplySecureServingOptions(o.SecureServing); err != nil {
 		return err
 	}
+	if _, err := genericAPIServerConfig.ApplyDelegatingAuthenticationOptions(o.Authentication); err != nil {
+		return err
+	}
+	if _, err := genericAPIServerConfig.ApplyDelegatingAuthorizationOptions(o.Authorization); err != nil {
+		return err
+	}
 
 	var err error
 	privilegedLoopbackToken := uuid.NewRandom().String()

hack/local-up-cluster.sh

@@ -444,7 +444,7 @@ EOF
     create_client_certkey client-ca kube-proxy system:kube-proxy system:nodes
     create_client_certkey client-ca controller system:controller system:masters
     create_client_certkey client-ca scheduler system:scheduler system:masters
-    create_client_certkey client-ca admin system:admin system:cluster-admins
+    create_client_certkey client-ca admin system:admin system:masters
 
     # Create auth proxy client ca
     sudo /bin/bash -e <<EOF
@@ -476,7 +476,7 @@ EOF
       --requestheader-username-headers=X-Remote-User \
       --requestheader-group-headers=X-Remote-Group \
       --requestheader-extra-headers-prefix=X-Remote-Extra- \
-      --requestheader-client-ca-file=${CERT_DIR}/auth-proxy-client-ca.crt \
+      --requestheader-client-ca-file="${CERT_DIR}/auth-proxy-client-ca.crt" \
       --requestheader-allowed-names=system:auth-proxy \
       --cors-allowed-origins="${API_CORS_ALLOWED_ORIGINS}" >"${APISERVER_LOG}" 2>&1 &
     APISERVER_PID=$!
@@ -486,6 +486,7 @@ EOF
     kube::util::wait_for_url "https://${API_HOST}:${API_SECURE_PORT}/version" "apiserver: " 1 ${WAIT_FOR_URL_API_SERVER} || exit 1
 
     # Create kubeconfigs for all components, using client certs
+    write_client_kubeconfig admin
     write_client_kubeconfig kubelet
     write_client_kubeconfig kube-proxy
     write_client_kubeconfig controller
@@ -509,11 +510,23 @@ EOF
 # start_discovery relies on certificates created by start_apiserver
 function start_discovery {
     # TODO generate serving certificates
-    
+    create_client_certkey client-ca discovery-auth system:discovery-auth
+    write_client_kubeconfig discovery-auth
+
+    # grant permission to run delegated authentication and authorization checks
+    kubectl create clusterrolebinding discovery:system:auth-delegator --clusterrole=system:auth-delegator --user=system:discovery-auth
+
     DISCOVERY_SERVER_LOG=/tmp/kubernetes-discovery.log
     ${CONTROLPLANE_SUDO} "${GO_OUT}/kubernetes-discovery" \
       --cert-dir="${CERT_DIR}" \
       --client-ca-file="${CERT_DIR}/client-ca-bundle.crt" \
+      --authentication-kubeconfig="${CERT_DIR}/discovery-auth.kubeconfig" \
+      --authorization-kubeconfig="${CERT_DIR}/discovery-auth.kubeconfig" \
+      --requestheader-username-headers=X-Remote-User \
+      --requestheader-group-headers=X-Remote-Group \
+      --requestheader-extra-headers-prefix=X-Remote-Extra- \
+      --requestheader-client-ca-file="${CERT_DIR}/auth-proxy-client-ca.crt" \
+      --requestheader-allowed-names=system:auth-proxy \
       --bind-address="${API_BIND_ADDR}" \
       --secure-port="${DISCOVERY_SECURE_PORT}" \
       --tls-ca-file="${ROOT_CA_FILE}" \
@@ -800,7 +813,7 @@ if [[ "${START_MODE}" != "kubeletonly" ]]; then
   start_etcd
   set_service_accounts
   start_apiserver
-  # start_discovery
+  start_discovery
   start_controller_manager
   start_kubeproxy
   start_kubedns

pkg/genericapiserver/config.go

@@ -343,6 +343,46 @@ func (c *Config) ApplyAuthenticationOptions(o *options.BuiltInAuthenticationOpti
 	return c, nil
 }
 
+func (c *Config) ApplyDelegatingAuthenticationOptions(o *options.DelegatingAuthenticationOptions) (*Config, error) {
+	if o == nil {
+		return c, nil
+	}
+
+	cfg, err := o.ToAuthenticationConfig()
+	if err != nil {
+		return nil, err
+	}
+	authenticator, securityDefinitions, err := cfg.New()
+	if err != nil {
+		return nil, err
+	}
+
+	c.Authenticator = authenticator
+	c.OpenAPIConfig.SecurityDefinitions = securityDefinitions
+	c.SupportsBasicAuth = false
+
+	return c, nil
+}
+
+func (c *Config) ApplyDelegatingAuthorizationOptions(o *options.DelegatingAuthorizationOptions) (*Config, error) {
+	if o == nil {
+		return c, nil
+	}
+
+	cfg, err := o.ToAuthorizationConfig()
+	if err != nil {
+		return nil, err
+	}
+	authorizer, err := cfg.New()
+	if err != nil {
+		return nil, err
+	}
+
+	c.Authorizer = authorizer
+
+	return c, nil
+}
+
 // ApplyOptions applies the run options to the method receiver and returns self
 func (c *Config) ApplyOptions(options *options.ServerRunOptions) *Config {
 	if len(options.AuditLogPath) != 0 {

pkg/genericapiserver/options/authorization.go

@@ -111,8 +111,9 @@ type DelegatingAuthorizationOptions struct {
 
 func NewDelegatingAuthorizationOptions() *DelegatingAuthorizationOptions {
 	return &DelegatingAuthorizationOptions{
-		AllowCacheTTL: 5 * time.Minute,
-		DenyCacheTTL:  30 * time.Second,
+		// very low for responsiveness, but high enough to handle storms
+		AllowCacheTTL: 10 * time.Second,
+		DenyCacheTTL:  10 * time.Second,
 	}
 }
 
@@ -125,6 +126,14 @@ func (s *DelegatingAuthorizationOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&s.RemoteKubeConfigFile, "authorization-kubeconfig", s.RemoteKubeConfigFile, ""+
 		"kubeconfig file pointing at the 'core' kubernetes server with enough rights to create "+
 		" subjectaccessreviews.authorization.k8s.io.")
+
+	fs.DurationVar(&s.AllowCacheTTL, "authorization-webhook-cache-authorized-ttl",
+		s.AllowCacheTTL,
+		"The duration to cache 'authorized' responses from the webhook authorizer.")
+
+	fs.DurationVar(&s.DenyCacheTTL,
+		"authorization-webhook-cache-unauthorized-ttl", s.DenyCacheTTL,
+		"The duration to cache 'unauthorized' responses from the webhook authorizer.")
 }
 
 func (s *DelegatingAuthorizationOptions) ToAuthorizationConfig() (authorizer.DelegatingAuthorizerConfig, error) {