diff --git a/vendor/go.etcd.io/etcd/etcdserver/api/v2http/capability.go b/vendor/go.etcd.io/etcd/etcdserver/api/v2http/capability.go
new file mode 100644
index 0000000..ed6c456
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/etcdserver/api/v2http/capability.go
@@ -0,0 +1,40 @@
+// Copyright 2015 The etcd 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 v2http
+
+import (
+	"fmt"
+	"net/http"
+
+	"go.etcd.io/etcd/etcdserver/api"
+	"go.etcd.io/etcd/etcdserver/api/v2http/httptypes"
+)
+
+func authCapabilityHandler(fn func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if !api.IsCapabilityEnabled(api.AuthCapability) {
+			notCapable(w, r, api.AuthCapability)
+			return
+		}
+		fn(w, r)
+	}
+}
+
+func notCapable(w http.ResponseWriter, r *http.Request, c api.Capability) {
+	herr := httptypes.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Not capable of accessing %s feature during rolling upgrades.", c))
+	if err := herr.WriteTo(w); err != nil {
+		plog.Debugf("error writing HTTPError (%v) to %s", err, r.RemoteAddr)
+	}
+}