/* * Copyright (c) 2024 Project CHIP Authors * All rights reserved. * * 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. */ /** * @brief The file implements the Matter Check-In counter * */ #pragma once #include #include #include namespace chip { namespace Protocols { namespace SecureChannel { /** * @brief * */ class CheckInCounter : public PersistedCounter { public: CheckInCounter(){}; ~CheckInCounter() override{}; /** * @brief Returns the next Check-In counter Value to use * * @return uint32_t Check-in Counter value to use */ inline uint32_t GetNextCheckInCounterValue() { return (mCounterValue + 1); }; /** * @brief Advances the current Check-In counter value to invalidate half of the values. * Function adds UINT32_MAX / 2 to the current counter value. Next time a Check-In message is sent, 1 is added to the * current value. * * @return CHIP_ERROR Any error returned by a write to persisted storage. */ CHIP_ERROR InvalidateHalfCheckInCounterValues(); /** * @brief Invalidates all the Check-In counter values. After this function is called, the new Check-In counter value will be * equal to current value minus 1 (with rollover) to mimic N -> UINT32_MAX -> N-1. Next time a Check-In message is sent, * 1 is added to the current value which will be an invalid counter value. * * @return CHIP_ERROR Any error returned by a write to persisted storage. */ CHIP_ERROR InvalidateAllCheckInCounterValues(); private: /** * @brief Get the Initial Counter Value for the Check-In counter * Initial value is randomized for the Check-In counter * * @return uint32_t random value */ inline uint32_t GetInitialCounterValue() override { return chip::Crypto::GetRandU32(); } }; } // namespace SecureChannel } // namespace Protocols } // namespace chip