Impersonation proxy cli arguments

cmd/pinniped/cmd/kubeconfig.go

@@ -78,6 +78,9 @@ type getKubeconfigConciergeParams struct {
 	authenticatorName     string
 	authenticatorType     string
 	apiGroupSuffix        string
+	caBundleData          string
+	endpoint              string
+	useImpersonationProxy bool
 }
 
 type getKubeconfigParams struct {
@@ -110,6 +113,10 @@ func kubeconfigCommand(deps kubeconfigDeps) *cobra.Command {
 	f.StringVar(&flags.concierge.authenticatorName, "concierge-authenticator-name", "", "Concierge authenticator name (default: autodiscover)")
 	f.StringVar(&flags.concierge.apiGroupSuffix, "concierge-api-group-suffix", "pinniped.dev", "Concierge API group suffix")
 
+	f.StringVar(&flags.concierge.caBundleData, "concierge-ca-bundle-data", "", "CA bundle to use when connecting to the concierge")
+	f.StringVar(&flags.concierge.endpoint, "concierge-endpoint", "", "API base for the Pinniped concierge endpoint")
+	f.BoolVar(&flags.concierge.useImpersonationProxy, "use-impersonation-proxy", false, "Whether the concierge cluster uses an impersonation proxy")
+
 	f.StringVar(&flags.oidc.issuer, "oidc-issuer", "", "OpenID Connect issuer URL (default: autodiscover)")
 	f.StringVar(&flags.oidc.clientID, "oidc-client-id", "pinniped-cli", "OpenID Connect client ID (default: autodiscover)")
 	f.Uint16Var(&flags.oidc.listenPort, "oidc-listen-port", 0, "TCP port for localhost listener (authorization code flow only)")
@@ -162,6 +169,10 @@ func runGetKubeconfig(out io.Writer, deps kubeconfigDeps, flags getKubeconfigPar
 	if err != nil {
 		return fmt.Errorf("could not load --kubeconfig/--kubeconfig-context: %w", err)
 	}
+	if flags.concierge.useImpersonationProxy {
+		cluster.CertificateAuthorityData = []byte(flags.concierge.caBundleData)
+		cluster.Server = flags.concierge.endpoint
+	}
 	clientset, err := deps.getClientset(clientConfig, flags.concierge.apiGroupSuffix)
 	if err != nil {
 		return fmt.Errorf("could not configure Kubernetes client: %w", err)
@@ -266,6 +277,13 @@ func configureConcierge(authenticator metav1.Object, flags *getKubeconfigParams,
 		}
 	}
 
+	if flags.concierge.endpoint == "" {
+		flags.concierge.endpoint = v1Cluster.Server
+	}
+	if flags.concierge.caBundleData == "" {
+		flags.concierge.caBundleData = base64.StdEncoding.EncodeToString(v1Cluster.CertificateAuthorityData)
+	}
+
 	// Append the flags to configure the Concierge credential exchange at runtime.
 	execConfig.Args = append(execConfig.Args,
 		"--enable-concierge",
@@ -273,9 +291,14 @@ func configureConcierge(authenticator metav1.Object, flags *getKubeconfigParams,
 		"--concierge-namespace="+flags.concierge.namespace,
 		"--concierge-authenticator-name="+flags.concierge.authenticatorName,
 		"--concierge-authenticator-type="+flags.concierge.authenticatorType,
-		"--concierge-endpoint="+v1Cluster.Server,
+		"--concierge-endpoint="+flags.concierge.endpoint,
-		"--concierge-ca-bundle-data="+base64.StdEncoding.EncodeToString(v1Cluster.CertificateAuthorityData),
+		"--concierge-ca-bundle-data="+flags.concierge.caBundleData,
 	)
+	if flags.concierge.useImpersonationProxy {
+		execConfig.Args = append(execConfig.Args,
+			"--use-impersonation-proxy",
+		)
+	}
 	return nil
 }
 

cmd/pinniped/cmd/kubeconfig_test.go

@@ -61,6 +61,8 @@ func TestGetKubeconfig(t *testing.T) {
 				      --concierge-api-group-suffix string     Concierge API group suffix (default "pinniped.dev")
 				      --concierge-authenticator-name string   Concierge authenticator name (default: autodiscover)
 				      --concierge-authenticator-type string   Concierge authenticator type (e.g., 'webhook', 'jwt') (default: autodiscover)
+				      --concierge-ca-bundle-data string       CA bundle to use when connecting to the concierge
+				      --concierge-endpoint string             API base for the Pinniped concierge endpoint
 				      --concierge-namespace string            Namespace in which the concierge was installed (default "pinniped-concierge")
 				  -h, --help                                  help for kubeconfig
 				      --kubeconfig string                     Path to kubeconfig file
@@ -76,6 +78,7 @@ func TestGetKubeconfig(t *testing.T) {
 				      --oidc-skip-browser                     During OpenID Connect login, skip opening the browser (just print the URL)
 				      --static-token string                   Instead of doing an OIDC-based login, specify a static token
 				      --static-token-env string               Instead of doing an OIDC-based login, read a static token from the environment
+					  --use-impersonation-proxy               Whether the concierge cluster uses an impersonation proxy
 			`),
 		},
 		{
@@ -506,6 +509,67 @@ func TestGetKubeconfig(t *testing.T) {
 			`, base64.StdEncoding.EncodeToString(testCA.Bundle())),
 			wantAPIGroupSuffix: "tuna.io",
 		},
+		{
+			name: "configure impersonation proxy with autodetected JWT authenticator",
+			args: []string{
+				"--kubeconfig", "./testdata/kubeconfig.yaml",
+				"--concierge-ca-bundle-data", "blah", // TODO make this more realistic, maybe do some validation?
+				"--concierge-endpoint", "https://impersonation-proxy-endpoint.test",
+				"--use-impersonation-proxy",
+			},
+			conciergeObjects: []runtime.Object{
+				&conciergev1alpha1.JWTAuthenticator{
+					ObjectMeta: metav1.ObjectMeta{Name: "test-authenticator", Namespace: "pinniped-concierge"},
+					Spec: conciergev1alpha1.JWTAuthenticatorSpec{
+						Issuer:   "https://example.com/issuer",
+						Audience: "test-audience",
+						TLS: &conciergev1alpha1.TLSSpec{
+							CertificateAuthorityData: base64.StdEncoding.EncodeToString(testCA.Bundle()),
+						},
+					},
+				},
+			},
+			wantStdout: here.Docf(`
+        		apiVersion: v1
+        		clusters:
+        		- cluster:
+        		    certificate-authority-data: YmxhaA==
+        		    server: https://impersonation-proxy-endpoint.test
+        		  name: pinniped
+        		contexts:
+        		- context:
+        		    cluster: pinniped
+        		    user: pinniped
+        		  name: pinniped
+        		current-context: pinniped
+        		kind: Config
+        		preferences: {}
+        		users:
+        		- name: pinniped
+        		  user:
+        		    exec:
+        		      apiVersion: client.authentication.k8s.io/v1beta1
+        		      args:
+        		      - login
+        		      - oidc
+        		      - --enable-concierge
+        		      - --concierge-api-group-suffix=pinniped.dev
+        		      - --concierge-namespace=pinniped-concierge
+        		      - --concierge-authenticator-name=test-authenticator
+        		      - --concierge-authenticator-type=jwt
+        		      - --concierge-endpoint=https://impersonation-proxy-endpoint.test
+        		      - --concierge-ca-bundle-data=blah
+        		      - --use-impersonation-proxy
+        		      - --issuer=https://example.com/issuer
+        		      - --client-id=pinniped-cli
+        		      - --scopes=offline_access,openid,pinniped:request-audience
+        		      - --ca-bundle-data=%s
+        		      - --request-audience=test-audience
+        		      command: '.../path/to/pinniped'
+        		      env: []
+        		      provideClusterInfo: true
+			`, base64.StdEncoding.EncodeToString(testCA.Bundle())),
+		},
 	}
 	for _, tt := range tests {
 		tt := tt

cmd/pinniped/cmd/login_oidc.go

@@ -16,6 +16,11 @@ import (
 	"path/filepath"
 	"time"
 
+	corev1 "k8s.io/api/core/v1"
+
+	authenticationv1alpha1 "go.pinniped.dev/generated/1.20/apis/concierge/authentication/v1alpha1"
+	loginv1alpha1 "go.pinniped.dev/generated/1.20/apis/concierge/login/v1alpha1"
+
 	"github.com/coreos/go-oidc/v3/oidc"
 	"github.com/spf13/cobra"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -65,6 +70,7 @@ type oidcLoginFlags struct {
 	conciergeEndpoint          string
 	conciergeCABundle          string
 	conciergeAPIGroupSuffix    string
+	useImpersonationProxy      bool
 }
 
 func oidcLoginCommand(deps oidcLoginCommandDeps) *cobra.Command {
@@ -94,6 +100,7 @@ func oidcLoginCommand(deps oidcLoginCommandDeps) *cobra.Command {
 	cmd.Flags().StringVar(&flags.conciergeEndpoint, "concierge-endpoint", "", "API base for the Pinniped concierge endpoint")
 	cmd.Flags().StringVar(&flags.conciergeCABundle, "concierge-ca-bundle-data", "", "CA bundle to use when connecting to the concierge")
 	cmd.Flags().StringVar(&flags.conciergeAPIGroupSuffix, "concierge-api-group-suffix", "pinniped.dev", "Concierge API group suffix")
+	cmd.Flags().BoolVar(&flags.useImpersonationProxy, "use-impersonation-proxy", false, "Whether the concierge cluster uses an impersonation proxy")
 
 	mustMarkHidden(&cmd, "debug-session-cache")
 	mustMarkRequired(&cmd, "issuer")
@@ -171,12 +178,21 @@ func runOIDCLogin(cmd *cobra.Command, deps oidcLoginCommandDeps, flags oidcLogin
 	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
 	defer cancel()
 
-	if concierge != nil {
+	// do a credential exchange request, unless impersonation proxy is configured
+	if concierge != nil && !flags.useImpersonationProxy {
 		cred, err = deps.exchangeToken(ctx, concierge, token.IDToken.Token)
 		if err != nil {
 			return fmt.Errorf("could not complete concierge credential exchange: %w", err)
 		}
 	}
+	if concierge != nil && flags.useImpersonationProxy {
+		// TODO add the right header???
+		req, err := execCredentialForImpersonationProxy(token, flags)
+		if err != nil {
+			return err
+		}
+		return json.NewEncoder(cmd.OutOrStdout()).Encode(req)
+	}
 	return json.NewEncoder(cmd.OutOrStdout()).Encode(cred)
 }
 func makeClient(caBundlePaths []string, caBundleData []string) (*http.Client, error) {
@@ -238,3 +254,36 @@ func mustGetConfigDir() string {
 	}
 	return filepath.Join(home, ".config", xdgAppName)
 }
+
+func execCredentialForImpersonationProxy(token *oidctypes.Token, flags oidcLoginFlags) (*clientauthv1beta1.ExecCredential, error) {
+	reqJSON, err := json.Marshal(&loginv1alpha1.TokenCredentialRequest{
+		ObjectMeta: metav1.ObjectMeta{
+			Namespace: flags.conciergeNamespace,
+		},
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "TokenCredentialRequest",
+			APIVersion: loginv1alpha1.GroupName + "/v1alpha1",
+		},
+		Spec: loginv1alpha1.TokenCredentialRequestSpec{
+			Token: token.AccessToken.Token, // TODO
+			Authenticator: corev1.TypedLocalObjectReference{
+				APIGroup: &authenticationv1alpha1.SchemeGroupVersion.Group,
+				Kind:     os.Getenv(flags.conciergeAuthenticatorType),
+				Name:     os.Getenv(flags.conciergeAuthenticatorName),
+			},
+		},
+	})
+	if err != nil {
+		return nil, err
+	}
+	encodedToken := base64.RawURLEncoding.EncodeToString(reqJSON)
+	return &clientauthv1beta1.ExecCredential{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "ExecCredential",
+			APIVersion: "client.authentication.k8s.io/v1beta1",
+		},
+		Status: &clientauthv1beta1.ExecCredentialStatus{
+			Token: encodedToken,
+		},
+	}, nil
+}

cmd/pinniped/cmd/login_oidc_test.go

@@ -74,6 +74,7 @@ func TestLoginOIDCCommand(t *testing.T) {
 				      --scopes strings                        OIDC scopes to request during login (default [offline_access,openid,pinniped:request-audience])
 				      --session-cache string                  Path to session cache file (default "` + cfgDir + `/sessions.yaml")
 				      --skip-browser                          Skip opening the browser (just print the URL)
+				      --use-impersonation-proxy               Whether the concierge cluster uses an impersonation proxy
 			`),
 		},
 		{