1/*
2 * Copyright 2014 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 SYSTEM_KEYMASTER_HMAC_OPERATION_H_
18#define SYSTEM_KEYMASTER_HMAC_OPERATION_H_
19
20#include "operation.h"
21
22#include <openssl/hmac.h>
23
24namespace keymaster {
25
26class HmacOperation : public Operation {
27  public:
28    HmacOperation(keymaster_purpose_t purpose, const uint8_t* key_data, size_t key_data_size,
29                  keymaster_digest_t digest, size_t mac_length, size_t min_mac_length);
30    ~HmacOperation();
31
32    virtual keymaster_error_t Begin(const AuthorizationSet& input_params,
33                                    AuthorizationSet* output_params);
34    virtual keymaster_error_t Update(const AuthorizationSet& additional_params, const Buffer& input,
35                                     AuthorizationSet* output_params, Buffer* output,
36                                     size_t* input_consumed);
37    virtual keymaster_error_t Abort();
38    virtual keymaster_error_t Finish(const AuthorizationSet& additional_params,
39                                     const Buffer& signature, AuthorizationSet* output_params,
40                                     Buffer* output);
41
42    keymaster_error_t error() { return error_; }
43
44  private:
45    HMAC_CTX ctx_;
46    keymaster_error_t error_;
47    const size_t mac_length_;
48    const size_t min_mac_length_;
49};
50
51/**
52 * Abstract base for HMAC operation factories.  This class does all of the work to create
53 * HMAC operations.
54 */
55class HmacOperationFactory : public OperationFactory {
56  public:
57    virtual KeyType registry_key() const { return KeyType(KM_ALGORITHM_HMAC, purpose()); }
58
59    virtual Operation* CreateOperation(const Key& key, const AuthorizationSet& begin_params,
60                                       keymaster_error_t* error);
61
62    virtual const keymaster_digest_t* SupportedDigests(size_t* digest_count) const;
63
64    virtual keymaster_purpose_t purpose() const = 0;
65};
66
67class HmacSignOperationFactory : public HmacOperationFactory {
68    keymaster_purpose_t purpose() const { return KM_PURPOSE_SIGN; }
69};
70
71class HmacVerifyOperationFactory : public HmacOperationFactory {
72    keymaster_purpose_t purpose() const { return KM_PURPOSE_VERIFY; }
73};
74
75}  // namespace keymaster
76
77#endif  // SYSTEM_KEYMASTER_HMAC_OPERATION_H_
78