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_KEY_H_
18#define SYSTEM_KEYMASTER_HMAC_KEY_H_
19
20#include "symmetric_key.h"
21
22namespace keymaster {
23
24const size_t kMinHmacLengthBits = 64;
25
26class HmacKeyFactory : public SymmetricKeyFactory {
27  public:
28    HmacKeyFactory(const KeymasterContext* context) : SymmetricKeyFactory(context) {}
29
30    keymaster_error_t LoadKey(const KeymasterKeyBlob& key_material,
31                              const AuthorizationSet& additional_params,
32                              const AuthorizationSet& hw_enforced,
33                              const AuthorizationSet& sw_enforced,
34                              UniquePtr<Key>* key) const override;
35
36    OperationFactory* GetOperationFactory(keymaster_purpose_t purpose) const override;
37
38  private:
39    bool key_size_supported(size_t key_size_bits) const override {
40        return key_size_bits > 0 && key_size_bits % 8 == 00 &&
41               key_size_bits <= 2048 /* Some RFC test cases require >1024-bit keys */;
42    }
43    keymaster_error_t validate_algorithm_specific_new_key_params(
44        const AuthorizationSet& key_description) const override;
45};
46
47class HmacKey : public SymmetricKey {
48  public:
49    HmacKey(const KeymasterKeyBlob& key_material, const AuthorizationSet& hw_enforced,
50            const AuthorizationSet& sw_enforced, keymaster_error_t* error)
51        : SymmetricKey(key_material, hw_enforced, sw_enforced, error) {}
52};
53
54}  // namespace keymaster
55
56#endif  // SYSTEM_KEYMASTER_HMAC_KEY_H_
57