ARMmbed
/
mbed-os
mirror of https://github.com/ARMmbed/mbed-os.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
mbed-os/features/mbedtls/targets/TARGET_STM/sha256_alt.c

235 lines
8.2 KiB
C
Raw Blame History

/*
* sha256_alt.c for SHA256 HASH
*******************************************************************************
* Copyright (c) 2017, STMicroelectronics
* 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 "mbedtls/sha256.h"
#if defined(MBEDTLS_SHA256_ALT)
#include "mbedtls/platform.h"
/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize( void *v, size_t n ) {
volatile unsigned char *p = v; while( n-- ) *p++ = 0;
}
static int st_sha256_restore_hw_context(mbedtls_sha256_context *ctx)
{
uint32_t i;
uint32_t tickstart;
/* allow multi-instance of HASH use: save context for HASH HW module CR */
/* Check that there is no HASH activity on going */
tickstart = HAL_GetTick();
while ((HASH->SR & (HASH_FLAG_BUSY | HASH_FLAG_DMAS)) != 0) {
if ((HAL_GetTick() - tickstart) > ST_SHA256_TIMEOUT) {
return 0; // timeout: HASH processor is busy
}
}
HASH->STR = ctx->ctx_save_str;
HASH->CR = (ctx->ctx_save_cr | HASH_CR_INIT);
for (i=0;i<38;i++) {
HASH->CSR[i] = ctx->ctx_save_csr[i];
}
return 1;
}
static int st_sha256_save_hw_context(mbedtls_sha256_context *ctx)
{
uint32_t i;
uint32_t tickstart;
/* Check that there is no HASH activity on going */
tickstart = HAL_GetTick();
while ((HASH->SR & (HASH_FLAG_BUSY | HASH_FLAG_DMAS)) != 0) {
if ((HAL_GetTick() - tickstart) > ST_SHA256_TIMEOUT) {
return 0; // timeout: HASH processor is busy
}
}
/* allow multi-instance of HASH use: restore context for HASH HW module CR */
ctx->ctx_save_cr = HASH->CR;
ctx->ctx_save_str = HASH->STR;
for (i=0;i<38;i++) {
ctx->ctx_save_csr[i] = HASH->CSR[i];
}
return 1;
}
void mbedtls_sha256_init( mbedtls_sha256_context *ctx )
{
mbedtls_zeroize( ctx, sizeof( mbedtls_sha256_context ) );
/* Enable HASH clock */
__HAL_RCC_HASH_CLK_ENABLE();
}
void mbedtls_sha256_free( mbedtls_sha256_context *ctx )
{
if( ctx == NULL )
return;
mbedtls_zeroize( ctx, sizeof( mbedtls_sha256_context ) );
}
void mbedtls_sha256_clone( mbedtls_sha256_context *dst,
const mbedtls_sha256_context *src )
{
*dst = *src;
}
int mbedtls_sha256_starts_ret( mbedtls_sha256_context *ctx, int is224 )
{
/* HASH IP initialization */
if (HAL_HASH_DeInit(&ctx->hhash_sha256) == HAL_ERROR) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
ctx->is224 = is224;
/* HASH Configuration */
ctx->hhash_sha256.Init.DataType = HASH_DATATYPE_8B;
/* clear CR ALGO value */
HASH->CR &= ~HASH_CR_ALGO_Msk;
if (HAL_HASH_Init(&ctx->hhash_sha256) == HAL_ERROR) {
// error found to be returned
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
if (st_sha256_save_hw_context(ctx) != 1) {
// return HASH_BUSY timeout Error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
return 0;
}
int mbedtls_internal_sha256_process( mbedtls_sha256_context *ctx, const unsigned char data[ST_SHA256_BLOCK_SIZE] )
{
if (st_sha256_restore_hw_context(ctx) != 1) {
// Return HASH_BUSY timeout error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
if (ctx->is224 == 0) {
if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, (uint8_t *) data, ST_SHA256_BLOCK_SIZE) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
} else {
if (HAL_HASHEx_SHA224_Accumulate(&ctx->hhash_sha256, (uint8_t *) data, ST_SHA256_BLOCK_SIZE) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
}
if (st_sha256_save_hw_context(ctx) != 1) {
// Return HASH_BUSY timeout error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
return 0;
}
int mbedtls_sha256_update_ret( mbedtls_sha256_context *ctx, const unsigned char *input, size_t ilen )
{
int err;
size_t currentlen = ilen;
if (st_sha256_restore_hw_context(ctx) != 1) {
// Return HASH_BUSY timeout error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
// store mechanism to accumulate ST_SHA256_BLOCK_SIZE bytes (512 bits) in the HW
if (currentlen == 0) { // only change HW status is size if 0
if(ctx->hhash_sha256.Phase == HAL_HASH_PHASE_READY) {
/* Select the SHA256 or SHA224 mode and reset the HASH processor core, so that the HASH will be ready to compute
the message digest of a new message */
if (ctx->is224 == 0) {
HASH->CR |= HASH_ALGOSELECTION_SHA256 | HASH_CR_INIT;
} else {
HASH->CR |= HASH_ALGOSELECTION_SHA224 | HASH_CR_INIT;
}
}
ctx->hhash_sha256.Phase = HAL_HASH_PHASE_PROCESS;
} else if (currentlen < (ST_SHA256_BLOCK_SIZE - ctx->sbuf_len)) {
// only buffurize
memcpy(ctx->sbuf + ctx->sbuf_len, input, currentlen);
ctx->sbuf_len += currentlen;
} else {
// fill buffer and process it
memcpy(ctx->sbuf + ctx->sbuf_len, input, (ST_SHA256_BLOCK_SIZE - ctx->sbuf_len));
currentlen -= (ST_SHA256_BLOCK_SIZE - ctx->sbuf_len);
err = mbedtls_internal_sha256_process(ctx, ctx->sbuf);
if (err != 0) {
return err;
}
// Process every input as long as it is %64 bytes, ie 512 bits
size_t iter = currentlen / ST_SHA256_BLOCK_SIZE;
if (iter !=0) {
if (ctx->is224 == 0) {
if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, (uint8_t *)(input + ST_SHA256_BLOCK_SIZE - ctx->sbuf_len), (iter * ST_SHA256_BLOCK_SIZE)) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
} else {
if (HAL_HASHEx_SHA224_Accumulate(&ctx->hhash_sha256, (uint8_t *)(input + ST_SHA256_BLOCK_SIZE - ctx->sbuf_len), (iter * ST_SHA256_BLOCK_SIZE)) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
}
}
// sbuf is completely accumulated, now copy up to 63 remaining bytes
ctx->sbuf_len = currentlen % ST_SHA256_BLOCK_SIZE;
if (ctx->sbuf_len !=0) {
memcpy(ctx->sbuf, input + ilen - ctx->sbuf_len, ctx->sbuf_len);
}
}
if (st_sha256_save_hw_context(ctx) != 1) {
// Return HASH_BUSY timeout error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
return 0;
}
int mbedtls_sha256_finish_ret( mbedtls_sha256_context *ctx, unsigned char output[32] )
{
if (st_sha256_restore_hw_context(ctx) != 1) {
// Return HASH_BUSY timeout error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
/* Last accumulation for extra bytes in sbuf_len */
/* This allows the HW flags to be in place in case mbedtls_sha256_update has not been called yet */
if (ctx->is224 == 0) {
if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, ctx->sbuf, ctx->sbuf_len) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
} else {
if (HAL_HASHEx_SHA224_Accumulate(&ctx->hhash_sha256, ctx->sbuf, ctx->sbuf_len) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
}
mbedtls_zeroize(ctx->sbuf, ST_SHA256_BLOCK_SIZE);
ctx->sbuf_len = 0;
__HAL_HASH_START_DIGEST();
if (ctx->is224 == 0) {
if (HAL_HASHEx_SHA256_Finish(&ctx->hhash_sha256, output, 10) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
} else {
if (HAL_HASHEx_SHA224_Finish(&ctx->hhash_sha256, output, 10) != 0) {
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
}
if (st_sha256_save_hw_context(ctx) != 1) {
// Return HASH_BUSY timeout error here
return MBEDTLS_ERR_SHA256_HW_ACCEL_FAILED;
}
return 0;
}
#endif /*MBEDTLS_SHA256_ALT*/
Reference in New Issue View Git Blame Copy Permalink