esp-idf/components/mbedtls/port/include/mbedtls/bignum.h
Angus Gratton 0927ec029e wpa_supplicant: Allow building with mbedTLS integration but no hardware MPI
Also disable the relevant function in bignum.h based on config, so fails at
compile not link time.

Closes https://github.com/espressif/esp-idf/issues/5321
2020-05-20 12:06:07 +10:00

81 lines
3.0 KiB
C

// Copyright 2015-2020 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.
#pragma once
#include_next "mbedtls/bignum.h"
#include "sdkconfig.h"
/**
* This is a wrapper for the main mbedtls/bignum.h. This wrapper
* provides a few additional ESP32-only functions.
*
* This is because we don't set MBEDTLS_BIGNUM_ALT in the same way we
* do for AES, SHA, etc. Because we still use most of the bignum.h
* implementation and just replace a few hardware accelerated
* functions (see MBEDTLS_MPI_EXP_MOD_ALT & MBEDTLS_MPI_MUL_MPI_ALT in
* esp_config.h).
*
* @note Unlike the other hardware accelerator support functions in esp32/hwcrypto, there is no
* generic "hwcrypto/bignum.h" header for using these functions without mbedTLS. The reason for this
* is that all of the function implementations depend strongly upon the mbedTLS MPI implementation.
*/
/**
* @brief Lock access to RSA Accelerator (MPI/bignum operations)
*
* RSA Accelerator hardware unit can only be used by one
* consumer at a time.
*
* @note This function is non-recursive (do not call it twice from the
* same task.)
*
* @note You do not need to call this if you are using the mbedTLS bignum.h
* API or esp_mpi_xxx functions. This function is only needed if you
* want to call ROM RSA functions or access the registers directly.
*
*/
void esp_mpi_acquire_hardware(void);
/**
* @brief Unlock access to RSA Accelerator (MPI/bignum operations)
*
* Has to be called once for each call to esp_mpi_acquire_hardware().
*
* @note You do not need to call this if you are using the mbedTLS bignum.h
* API or esp_mpi_xxx functions. This function is only needed if you
* want to call ROM RSA functions or access the registers directly.
*/
void esp_mpi_release_hardware(void);
#if CONFIG_MBEDTLS_HARDWARE_MPI
/* @brief MPI modular mupltiplication function
*
* Calculates Z = (X * Y) mod M using MPI hardware acceleration.
*
* This is not part of the standard mbedTLS bignum API.
*
* @note All of X, Y & Z should be less than 4096 bit long or an error is returned.
*
* @param Z Result bignum, should be pre-initialised with mbedtls_mpi_init().
* @param X First multiplication argument.
* @param Y Second multiplication argument.
* @param M Modulus value for result.
*
* @return 0 on success, mbedTLS MPI error codes on failure.
*/
int esp_mpi_mul_mpi_mod(mbedtls_mpi *Z, const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M);
#endif // CONFIG_MBEDTLS_HARDWARE_MPI