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mbedtls: merge changes from C3

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This commit is contained in:
Marius Vikhammer
2020-12-22 19:37:59 +08:00
parent c3ba995f2c
commit 1b6891c5d8
16 changed files with 652 additions and 115 deletions
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230
components/mbedtls/port/esp32c3/bignum.c Normal file
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/**
* \brief Multi-precision integer library, ESP32 C3 hardware accelerated parts
*
* based on mbedTLS implementation
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* Additions Copyright (C) 2016-2020, Espressif Systems (Shanghai) PTE Ltd
* SPDX-License-Identifier: Apache-2.0
*
* 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.
*
*/
#include <string.h>
#include <sys/param.h>
#include "soc/hwcrypto_periph.h"
#include "driver/periph_ctrl.h"
#include "mbedtls/bignum.h"
#include "bignum_impl.h"
#include "soc/system_reg.h"
#include "soc/periph_defs.h"
#include "esp_crypto_lock.h"
size_t esp_mpi_hardware_words(size_t words)
{
return words;
}
void esp_mpi_enable_hardware_hw_op( void )
{
esp_crypto_mpi_lock_acquire();
/* Enable RSA hardware */
periph_module_enable(PERIPH_RSA_MODULE);
REG_CLR_BIT(SYSTEM_RSA_PD_CTRL_REG, SYSTEM_RSA_MEM_PD);
while (REG_READ(RSA_QUERY_CLEAN_REG) != 1) {
}
// Note: from enabling RSA clock to here takes about 1.3us
}
void esp_mpi_disable_hardware_hw_op( void )
{
REG_SET_BIT(SYSTEM_RSA_PD_CTRL_REG, SYSTEM_RSA_MEM_PD);
/* Disable RSA hardware */
periph_module_disable(PERIPH_RSA_MODULE);
esp_crypto_mpi_lock_release();
}
/* Copy mbedTLS MPI bignum 'mpi' to hardware memory block at 'mem_base'.
If num_words is higher than the number of words in the bignum then
these additional words will be zeroed in the memory buffer.
*/
static inline void mpi_to_mem_block(uint32_t mem_base, const mbedtls_mpi *mpi, size_t num_words)
{
uint32_t *pbase = (uint32_t *)mem_base;
uint32_t copy_words = MIN(num_words, mpi->n);
/* Copy MPI data to memory block registers */
for (int i = 0; i < copy_words; i++) {
pbase[i] = mpi->p[i];
}
/* Zero any remaining memory block data */
for (int i = copy_words; i < num_words; i++) {
pbase[i] = 0;
}
}
/* Read mbedTLS MPI bignum back from hardware memory block.
Reads num_words words from block.
*/
static inline void mem_block_to_mpi(mbedtls_mpi *x, uint32_t mem_base, int num_words)
{
/* Copy data from memory block registers */
const size_t REG_WIDTH = sizeof(uint32_t);
for (size_t i = 0; i < num_words; i++) {
x->p[i] = REG_READ(mem_base + (i * REG_WIDTH));
}
/* Zero any remaining limbs in the bignum, if the buffer is bigger
than num_words */
for (size_t i = num_words; i < x->n; i++) {
x->p[i] = 0;
}
}
/* Begin an RSA operation. op_reg specifies which 'START' register
to write to.
*/
static inline void start_op(uint32_t op_reg)
{
/* Clear interrupt status */
REG_WRITE(RSA_CLEAR_INTERRUPT_REG, 1);
/* Note: above REG_WRITE includes a memw, so we know any writes
to the memory blocks are also complete. */
REG_WRITE(op_reg, 1);
}
/* Wait for an RSA operation to complete.
*/
static inline void wait_op_complete(void)
{
while (REG_READ(RSA_QUERY_INTERRUPT_REG) != 1)
{ }
/* clear the interrupt */
REG_WRITE(RSA_CLEAR_INTERRUPT_REG, 1);
}
/* Read result from last MPI operation */
void esp_mpi_read_result_hw_op(mbedtls_mpi *Z, size_t z_words)
{
wait_op_complete();
mem_block_to_mpi(Z, RSA_MEM_Z_BLOCK_BASE, z_words);
}
/* Z = (X * Y) mod M
Not an mbedTLS function
*/
void esp_mpi_mul_mpi_mod_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, const mbedtls_mpi *Rinv, mbedtls_mpi_uint Mprime, size_t num_words)
{
REG_WRITE(RSA_LENGTH_REG, (num_words - 1));
/* Load M, X, Rinv, Mprime (Mprime is mod 2^32) */
mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, num_words);
mpi_to_mem_block(RSA_MEM_Y_BLOCK_BASE, Y, num_words);
mpi_to_mem_block(RSA_MEM_M_BLOCK_BASE, M, num_words);
mpi_to_mem_block(RSA_MEM_RB_BLOCK_BASE, Rinv, num_words);
REG_WRITE(RSA_M_DASH_REG, Mprime);
start_op(RSA_MOD_MULT_START_REG);
}
/* Z = (X ^ Y) mod M
*/
void esp_mpi_exp_mpi_mod_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, const mbedtls_mpi *M, const mbedtls_mpi *Rinv, mbedtls_mpi_uint Mprime, size_t num_words)
{
size_t y_bits = mbedtls_mpi_bitlen(Y);
REG_WRITE(RSA_LENGTH_REG, (num_words - 1));
/* Load M, X, Rinv, Mprime (Mprime is mod 2^32) */
mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, num_words);
mpi_to_mem_block(RSA_MEM_Y_BLOCK_BASE, Y, num_words);
mpi_to_mem_block(RSA_MEM_M_BLOCK_BASE, M, num_words);
mpi_to_mem_block(RSA_MEM_RB_BLOCK_BASE, Rinv, num_words);
REG_WRITE(RSA_M_DASH_REG, Mprime);
/* Enable acceleration options */
REG_WRITE(RSA_CONSTANT_TIME_REG, 0);
REG_WRITE(RSA_SEARCH_ENABLE_REG, 1);
REG_WRITE(RSA_SEARCH_POS_REG, y_bits - 1);
/* Execute first stage montgomery multiplication */
start_op(RSA_MODEXP_START_REG);
REG_WRITE(RSA_SEARCH_ENABLE_REG, 0);
}
/* Z = X * Y */
void esp_mpi_mul_mpi_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, size_t num_words)
{
/* Copy X (right-extended) & Y (left-extended) to memory block */
mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, num_words);
mpi_to_mem_block(RSA_MEM_Z_BLOCK_BASE + num_words * 4, Y, num_words);
/* NB: as Y is left-extended, we don't zero the bottom words_mult words of Y block.
This is OK for now because zeroing is done by hardware when we do esp_mpi_acquire_hardware().
*/
REG_WRITE(RSA_LENGTH_REG, (num_words * 2 - 1));
start_op(RSA_MULT_START_REG);
}
/**
* @brief Special-case of (X * Y), where we use hardware montgomery mod
multiplication to calculate result where either A or B are >2048 bits so
can't use the standard multiplication method.
*
*/
void esp_mpi_mult_mpi_failover_mod_mult_hw_op(const mbedtls_mpi *X, const mbedtls_mpi *Y, size_t num_words)
{
/* M = 2^num_words - 1, so block is entirely FF */
for (int i = 0; i < num_words; i++) {
REG_WRITE(RSA_MEM_M_BLOCK_BASE + i * 4, UINT32_MAX);
}
/* Mprime = 1 */
REG_WRITE(RSA_M_DASH_REG, 1);
REG_WRITE(RSA_LENGTH_REG, num_words - 1);
/* Load X & Y */
mpi_to_mem_block(RSA_MEM_X_BLOCK_BASE, X, num_words);
mpi_to_mem_block(RSA_MEM_Y_BLOCK_BASE, Y, num_words);
/* Rinv = 1, write first word */
REG_WRITE(RSA_MEM_RB_BLOCK_BASE, 1);
/* Zero out rest of the Rinv words */
for (int i = 1; i < num_words; i++) {
REG_WRITE(RSA_MEM_RB_BLOCK_BASE + i * 4, 0);
}
start_op(RSA_MOD_MULT_START_REG);
}