hmac_session_impl.h revision 4dc4629c415e7ca90ff146d7bb75b5646ecd8b17 
1//
2// Copyright (C) 2015 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
17#ifndef TRUNKS_HMAC_SESSION_IMPL_H_
18#define TRUNKS_HMAC_SESSION_IMPL_H_
19
20#include "trunks/hmac_session.h"
21
22#include <string>
23
24#include <base/macros.h>
25
26#include "trunks/hmac_authorization_delegate.h"
27#include "trunks/session_manager.h"
28#include "trunks/trunks_export.h"
29#include "trunks/trunks_factory.h"
30
31namespace trunks {
32
33// This class implements the HmacSession interface. It is used for
34// keeping track of the HmacAuthorizationDelegate used for commands, and to
35// provide authorization for commands that need it. It is instantiated by
36// TpmUtilityImpl. If we need to use this class outside of TpmUtility, we
37// can use it as below:
38// TrunksFactoryImpl factory;
39// HmacSessionImpl session(factory);
40// session.StartBoundSession(bind_entity, bind_authorization, true);
41// session.SetEntityAuthorizationValue(entity_authorization);
42// factory.GetTpm()->RSA_EncrpytSync(_,_,_,_, session.GetDelegate());
43// NOTE: StartBoundSession/StartUnboundSession should not be called before
44// TPM Ownership is taken. This is because starting a session uses the
45// SaltingKey, which is only created after ownership is taken.
46class TRUNKS_EXPORT HmacSessionImpl : public HmacSession {
47 public:
48  // The constructor for HmacAuthroizationSession needs a factory. In
49  // producation code, this factory is used to access the TPM class to forward
50  // commands to the TPM. In test code, this is used to mock out the TPM calls.
51  explicit HmacSessionImpl(const TrunksFactory& factory);
52  ~HmacSessionImpl() override;
53
54  // HmacSession methods.
55  AuthorizationDelegate* GetDelegate() override;
56  TPM_RC StartBoundSession(TPMI_DH_ENTITY bind_entity,
57                           const std::string& bind_authorization_value,
58                           bool enable_encryption) override;
59  TPM_RC StartUnboundSession(bool enable_encryption) override;
60  void SetEntityAuthorizationValue(const std::string& value) override;
61  void SetFutureAuthorizationValue(const std::string& value) override;
62
63 private:
64  // This factory is only set in the constructor and is used to instantiate
65  // The TPM class to forward commands to the TPM chip.
66  const TrunksFactory& factory_;
67  // This delegate is what provides authorization to commands. It is what is
68  // returned when the GetDelegate method is called.
69  HmacAuthorizationDelegate hmac_delegate_;
70  // This object is used to manage the TPM session associated with this
71  // HmacSession.
72  scoped_ptr<SessionManager> session_manager_;
73
74  friend class HmacSessionTest;
75  DISALLOW_COPY_AND_ASSIGN(HmacSessionImpl);
76};
77
78}  // namespace trunks
79
80#endif  // TRUNKS_HMAC_SESSION_IMPL_H_
81