From 8eb7cfb296fd568d68d8eb288a878ac9206ed0a0 Mon Sep 17 00:00:00 2001
From: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Date: Tue, 27 Feb 2018 16:05:27 +0900
Subject: [PATCH] auth: a new auth token provider nop

This commit adds a new auth token provider named nop. The nop provider
refuses every Authenticate() request so CN based authentication can
only be allowed. If the tokenOpts parameter of auth.NewTokenProvider()
is empty, the provider will be used.
---
 auth/nop.go   | 35 +++++++++++++++++++++++++++++++++++
 auth/store.go |  2 ++
 2 files changed, 37 insertions(+)
 create mode 100644 auth/nop.go

diff --git a/auth/nop.go b/auth/nop.go
new file mode 100644
index 00000000000..d4378747bd8
--- /dev/null
+++ b/auth/nop.go
@@ -0,0 +1,35 @@
+// Copyright 2018 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 auth
+
+import (
+	"context"
+)
+
+type tokenNop struct{}
+
+func (t *tokenNop) enable()                         {}
+func (t *tokenNop) disable()                        {}
+func (t *tokenNop) invalidateUser(string)           {}
+func (t *tokenNop) genTokenPrefix() (string, error) { return "", nil }
+func (t *tokenNop) info(ctx context.Context, token string, rev uint64) (*AuthInfo, bool) {
+	return nil, false
+}
+func (t *tokenNop) assign(ctx context.Context, username string, revision uint64) (string, error) {
+	return "", ErrAuthFailed
+}
+func newTokenProviderNop() (*tokenNop, error) {
+	return &tokenNop{}, nil
+}
diff --git a/auth/store.go b/auth/store.go
index d379ffa8e8a..44d2d5359aa 100644
--- a/auth/store.go
+++ b/auth/store.go
@@ -1055,6 +1055,8 @@ func NewTokenProvider(tokenOpts string, indexWaiter func(uint64) <-chan struct{}
 		return newTokenProviderSimple(indexWaiter), nil
 	case "jwt":
 		return newTokenProviderJWT(typeSpecificOpts)
+	case "":
+		return newTokenProviderNop()
 	default:
 		plog.Errorf("unknown token type: %s", tokenType)
 		return nil, ErrInvalidAuthOpts