Update vendor

vendor/k8s.io/apiserver/pkg/authentication/authenticator/audagnostic.go

@@ -0,0 +1,90 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package authenticator
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+)
+
+func authenticate(ctx context.Context, implicitAuds Audiences, authenticate func() (*Response, bool, error)) (*Response, bool, error) {
+	targetAuds, ok := AudiencesFrom(ctx)
+	// We can remove this once api audiences is never empty. That will probably
+	// be N releases after TokenRequest is GA.
+	if !ok {
+		return authenticate()
+	}
+	auds := implicitAuds.Intersect(targetAuds)
+	if len(auds) == 0 {
+		return nil, false, nil
+	}
+	resp, ok, err := authenticate()
+	if err != nil || !ok {
+		return nil, false, err
+	}
+	if len(resp.Audiences) > 0 {
+		// maybe the authenticator was audience aware after all.
+		return nil, false, fmt.Errorf("audience agnostic authenticator wrapped an authenticator that returned audiences: %q", resp.Audiences)
+	}
+	resp.Audiences = auds
+	return resp, true, nil
+}
+
+type audAgnosticRequestAuthenticator struct {
+	implicit Audiences
+	delegate Request
+}
+
+var _ = Request(&audAgnosticRequestAuthenticator{})
+
+func (a *audAgnosticRequestAuthenticator) AuthenticateRequest(req *http.Request) (*Response, bool, error) {
+	return authenticate(req.Context(), a.implicit, func() (*Response, bool, error) {
+		return a.delegate.AuthenticateRequest(req)
+	})
+}
+
+// WrapAudienceAgnosticRequest wraps an audience agnostic request authenticator
+// to restrict its accepted audiences to a set of implicit audiences.
+func WrapAudienceAgnosticRequest(implicit Audiences, delegate Request) Request {
+	return &audAgnosticRequestAuthenticator{
+		implicit: implicit,
+		delegate: delegate,
+	}
+}
+
+type audAgnosticTokenAuthenticator struct {
+	implicit Audiences
+	delegate Token
+}
+
+var _ = Token(&audAgnosticTokenAuthenticator{})
+
+func (a *audAgnosticTokenAuthenticator) AuthenticateToken(ctx context.Context, tok string) (*Response, bool, error) {
+	return authenticate(ctx, a.implicit, func() (*Response, bool, error) {
+		return a.delegate.AuthenticateToken(ctx, tok)
+	})
+}
+
+// WrapAudienceAgnosticToken wraps an audience agnostic token authenticator to
+// restrict its accepted audiences to a set of implicit audiences.
+func WrapAudienceAgnosticToken(implicit Audiences, delegate Token) Token {
+	return &audAgnosticTokenAuthenticator{
+		implicit: implicit,
+		delegate: delegate,
+	}
+}