// Copyright 2020 Espressif Systems (Shanghai) PTE LTD // // 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. #ifndef _ROM_HMAC_H_ #define _ROM_HMAC_H_ #ifdef __cplusplus extern "C" { #endif #include <stdint.h> #include <stdlib.h> #include "efuse.h" void ets_hmac_enable(void); void ets_hmac_disable(void); /* Use the "upstream" HMAC key (ETS_EFUSE_KEY_PURPOSE_HMAC_UP) to digest a message. */ int ets_hmac_calculate_message(ets_efuse_block_t key_block, const void *message, size_t message_len, uint8_t *hmac); /* Calculate a downstream HMAC message to temporarily enable JTAG, or to generate a Digital Signature data decryption key. - purpose must be ETS_EFUSE_KEY_PURPOSE_HMAC_DOWN_DIGITAL_SIGNATURE or ETS_EFUSE_KEY_PURPOSE_HMAC_DOWN_JTAG - key_block must be in range ETS_EFUSE_BLOCK_KEY0 toETS_EFUSE_BLOCK_KEY6. This efuse block must have the corresponding purpose set in "purpose", or ETS_EFUSE_KEY_PURPOSE_HMAC_DOWN_ALL. The result of this HMAC calculation is only made available "downstream" to the corresponding hardware module, and cannot be accessed by software. */ int ets_hmac_calculate_downstream(ets_efuse_block_t key_block, ets_efuse_purpose_t purpose); /* Invalidate a downstream HMAC value previously calculated by ets_hmac_calculate_downstream(). * * - purpose must match a previous call to ets_hmac_calculate_downstream(). * * After this function is called, the corresponding internal operation (JTAG or DS) will no longer * have access to the generated key. */ int ets_hmac_invalidate_downstream(ets_efuse_purpose_t purpose); #ifdef __cplusplus } #endif #endif // _ROM_HMAC_H_