1 //
2 // Copyright (C) 2020 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 //      http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 
16 #pragma once
17 
18 #include <tss2/tss2_esys.h>
19 
20 namespace cuttlefish {
21 
22 /**
23  * Authorization wrapper for TPM2 calls.
24  *
25  * Most methods in tss2_esys.h take 3 ESYS_TR values for sessions and
26  * authorization, with constraints that unused authorizations are all
27  * ESYS_TR_NONE and are all at the end.
28  *
29  * This class is a convenience for specifying between 1 and 3
30  * authorizations concisely and enforcing that the constraints are met.
31  */
32 class TpmAuth {
33 public:
34   TpmAuth(ESYS_TR auth1);
35   TpmAuth(ESYS_TR auth1, ESYS_TR auth2);
36   TpmAuth(ESYS_TR auth1, ESYS_TR auth2, ESYS_TR auth3);
37 
38   ESYS_TR auth1() const;
39   ESYS_TR auth2() const;
40   ESYS_TR auth3() const;
41 private:
42   ESYS_TR auth1_;
43   ESYS_TR auth2_;
44   ESYS_TR auth3_;
45 };
46 
47 }  // namespace cuttlefish
48