|  | /* | 
|  | * Copyright (C) 2020 The Android Open Source Project | 
|  | * | 
|  | * 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. | 
|  | */ | 
|  |  | 
|  | #include <array> | 
|  |  | 
|  | namespace android { | 
|  | /** | 
|  | * Invalid value of HMAC - SHA256. Any events with this HMAC value will be marked as not verified. | 
|  | */ | 
|  | constexpr std::array<uint8_t, 32> INVALID_HMAC = {0}; | 
|  |  | 
|  | class HmacKeyManager { | 
|  | public: | 
|  | HmacKeyManager(); | 
|  | std::array<uint8_t, 32> sign(const uint8_t* data, size_t size) const; | 
|  | private: | 
|  | const std::array<uint8_t, 128> mHmacKey; | 
|  | }; | 
|  | } // namespace android |