/* Copyright 2021 Google LLC. All Rights Reserved. This file and proprietary
   source code may only be used and distributed under the Widevine
   License Agreement. */

#ifndef OEMCRYPTO_TA_WTPI_CLOCK_INTERFACE_LAYER2_H_
#define OEMCRYPTO_TA_WTPI_CLOCK_INTERFACE_LAYER2_H_

#include <stdint.h>

#include "OEMCryptoCENC.h"

#ifdef __cplusplus
extern "C" {
#endif

/** @defgroup secure-timer  Non-monotonic Secure Clock
 *
 * Partners implementing a porting layer may either
 * 1. Implement wtpi_persistent_storage_layer2.h and this
 *    wtpi_clock_interface_layer2.h, and then use the reference implementation
 *    wtpi_clock_and_gn_layer1.c for the clock and generation interfaces. This
 *    is preferred if the hardware secure timer resets to 0 whenever the device
 *    is inactive.
 * or
 * 2. Implement both wtpi_clock_interface_layer1.h and
 *    wtpi_generation_number_interface.h. This is preferred if the system has a
 *    hardware secure wall clock.
 *
 * @{
 */

/**
 * Retrieves the value of the secure timer and stores it in |time_in_s|.
 *
 * This timer should be secure and monotonic, but we allow it to reset to
 * 0 whenever the system reboots.
 *
 * Caller retains ownership of all pointers.
 *
 * @param[out] time_in_s: pointer to system time, in seconds.
 *
 * @retval OEMCrypto_ERROR_INVALID_CONTEXT if time_in_s is a null pointer
 * @retval OEMCrypto_SUCCESS on success
 */
OEMCryptoResult WTPI_GetSecureTimer(uint64_t* time_in_s);

/// @}

#ifdef __cplusplus
}
#endif

#endif /* OEMCRYPTO_TA_WTPI_CLOCK_INTERFACE_LAYER2_H_ */