83 lines
2.2 KiB
C
83 lines
2.2 KiB
C
|
#pragma once
|
||
|
|
|
||
|
|
#include <stdint.h>
|
||
|
|
|
||
|
|
class Storage {
|
||
|
|
|
||
|
|
public:
|
||
|
|
|
||
|
|
Storage(uint8_t remoteDeviceCount) : remoteDeviceCount(remoteDeviceCount) { };
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Initialize the use of the message counter API
|
||
|
|
*
|
||
|
|
* The message counter is stored in EEPROM, which must be initialized before use.
|
||
|
|
*
|
||
|
|
* @note The ESP32 does not have a true EEPROM,
|
||
|
|
* which is emulated using a section of the flash memory.
|
||
|
|
*/
|
||
|
|
void configure();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Check if a device ID is allowed
|
||
|
|
*
|
||
|
|
* @param deviceId The ID to check
|
||
|
|
* @return true The id is valid
|
||
|
|
* @return false The id is invalid
|
||
|
|
*/
|
||
|
|
bool isDeviceIdValid(uint8_t deviceId);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Check if a received counter is valid
|
||
|
|
*
|
||
|
|
* The counter is valid if it is larger than the previous counter
|
||
|
|
* (larger or equal to the next expected counter).
|
||
|
|
*
|
||
|
|
* @param counter The counter to check
|
||
|
|
* @return true The counter is valid
|
||
|
|
* @return false The counter belongs to an old message
|
||
|
|
*/
|
||
|
|
bool isMessageCounterValid(uint32_t counter, uint8_t deviceId);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Mark a counter of a message as used.
|
||
|
|
*
|
||
|
|
* The counter value is stored in EEPROM to persist across restarts.
|
||
|
|
*
|
||
|
|
* All messages with counters lower than the given one will become invalid.
|
||
|
|
*
|
||
|
|
* @param counter The counter used in the last message.
|
||
|
|
*/
|
||
|
|
void didUseMessageCounter(uint32_t counter, uint8_t deviceId);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Get the expected count for the next message.
|
||
|
|
*
|
||
|
|
* The counter is stored in EEPROM to persist across restarts
|
||
|
|
*
|
||
|
|
* @return The next counter to use by the remote
|
||
|
|
*/
|
||
|
|
uint32_t getNextMessageCounter(uint8_t deviceId);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Print info about the current message counter to the serial output
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
void printMessageCounters();
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Reset the message counter.
|
||
|
|
*
|
||
|
|
* @warning The counter should never be reset in production environments,
|
||
|
|
* and only together with a new secret key. Otherwise old messages may be
|
||
|
|
* used for replay attacks.
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
void resetMessageCounters();
|
||
|
|
|
||
|
|
private:
|
||
|
|
|
||
|
|
uint8_t remoteDeviceCount;
|
||
|
|
|
||
|
|
void setMessageCounter(uint32_t counter, uint8_t deviceId);
|
||
|
|
};
|