Skip to content

STM32L486RG/mbedtls: add aes hw acceleration #4163

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Jul 6, 2017
Merged

STM32L486RG/mbedtls: add aes hw acceleration #4163

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
2da3128
STM32L486RG/mbedtls: add aes hw acceleration
adustm Mar 16, 2017
d19c9ea
STM32L486RG/mbedtls: add aes hw acceleration
adustm Mar 16, 2017
e2c96e9
Move definitions in aes_alt.c + Factorize code
adustm Jun 16, 2017
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 25 additions & 0 deletions features/mbedtls/targets/TARGET_STM/TARGET_STM32L4/TARGET_NUCLEO_L486RG/mbedtls_device.h
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,25 @@
/*
* mbedtls_device.h
*******************************************************************************
* 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.
*
*/
#ifndef MBEDTLS_DEVICE_H
#define MBEDTLS_DEVICE_H

#define MBEDTLS_AES_ALT

#endif /* MBEDTLS_DEVICE_H */
112 changes: 73 additions & 39 deletions features/mbedtls/targets/TARGET_STM/aes_alt.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -23,22 +23,34 @@

#if defined(MBEDTLS_AES_ALT)

#if defined(TARGET_STM32L486xG)
//the following defines are provided to maintain compatibility between STM32 families
#define __HAL_RCC_CRYP_CLK_ENABLE __HAL_RCC_AES_CLK_ENABLE
#define __HAL_RCC_CRYP_FORCE_RESET __HAL_RCC_AES_FORCE_RESET
#define __HAL_RCC_CRYP_RELEASE_RESET __HAL_RCC_AES_RELEASE_RESET
#define CRYP AES
#endif

static int aes_set_key( mbedtls_aes_context *ctx, const unsigned char *key, unsigned int keybits )
{
switch( keybits )
{
switch( keybits ) {
case 128:
ctx->hcryp_aes.Init.KeySize = CRYP_KEYSIZE_128B;
memcpy(ctx->aes_key, key, 16);
break;
ctx->hcryp_aes.Init.KeySize = CRYP_KEYSIZE_128B;
memcpy(ctx->aes_key, key, 16);
break;
case 192:
ctx->hcryp_aes.Init.KeySize = CRYP_KEYSIZE_192B;
memcpy(ctx->aes_key, key, 24);
break;
#if defined (TARGET_STM32L486xG)
return(MBEDTLS_ERR_AES_INVALID_KEY_LENGTH);
#else
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The alternative implementation should support the full API. If HW doesn't support, then the SW implementation should be used

Copy link
Contributor

@yanesca yanesca Jun 8, 2017 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This was true at the time of the comment, but since then it has been decided that AES192 is and exception from this rule and hardware drivers not supporting AES192 can return an error.

ctx->hcryp_aes.Init.KeySize = CRYP_KEYSIZE_192B;
memcpy(ctx->aes_key, key, 24);
break;
#endif

case 256:
ctx->hcryp_aes.Init.KeySize = CRYP_KEYSIZE_256B;
memcpy(ctx->aes_key, key, 32);
break;
ctx->hcryp_aes.Init.KeySize = CRYP_KEYSIZE_256B;
memcpy(ctx->aes_key, key, 32);
break;
default : return( MBEDTLS_ERR_AES_INVALID_KEY_LENGTH );
}

Expand All @@ -52,6 +64,9 @@ static int aes_set_key( mbedtls_aes_context *ctx, const unsigned char *key, unsi
__HAL_RCC_CRYP_CLK_ENABLE();

ctx->hcryp_aes.Init.pKey = ctx->aes_key;
#if defined (TARGET_STM32L486xG)
ctx->hcryp_aes.Init.KeyWriteFlag = CRYP_KEY_WRITE_ENABLE;
#endif
if (HAL_CRYP_Init(&ctx->hcryp_aes) == HAL_ERROR)
return (HAL_ERROR);

Expand All @@ -62,7 +77,8 @@ static int aes_set_key( mbedtls_aes_context *ctx, const unsigned char *key, unsi
}

/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize( void *v, size_t n ) {
static void mbedtls_zeroize( void *v, size_t n )
{
volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
}

Expand Down Expand Up @@ -114,14 +130,11 @@ int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
/* allow multi-instance of CRYP use: restore context for CRYP hw module */
ctx->hcryp_aes.Instance->CR = ctx->ctx_save_cr;

if(mode == MBEDTLS_AES_DECRYPT) /* AES decryption */
{
if(mode == MBEDTLS_AES_DECRYPT) { /* AES decryption */
ctx->hcryp_aes.Init.DataType = CRYP_DATATYPE_8B;
ctx->hcryp_aes.Init.pKey = ctx->aes_key;
mbedtls_aes_decrypt( ctx, input, output );
}
else /* AES encryption */
{
} else { /* AES encryption */
ctx->hcryp_aes.Init.DataType = CRYP_DATATYPE_8B;
ctx->hcryp_aes.Init.pKey = ctx->aes_key;
mbedtls_aes_encrypt( ctx, input, output );
Expand All @@ -133,6 +146,31 @@ int mbedtls_aes_crypt_ecb( mbedtls_aes_context *ctx,
}

#if defined(MBEDTLS_CIPHER_MODE_CBC)
#if defined (TARGET_STM32L486xG)
static int st_hal_cryp_cbc( mbedtls_aes_context *ctx, uint32_t opmode, size_t length,
unsigned char iv[16], uint8_t *input, uint8_t *output)
{
int status = 0;
ctx->hcryp_aes.Init.pInitVect = &iv[0]; // used in process, not in the init
if ((ctx->hcryp_aes.Init.OperatingMode != opmode) || \
(ctx->hcryp_aes.Init.ChainingMode != CRYP_CHAINMODE_AES_CBC) || \
(ctx->hcryp_aes.Init.KeyWriteFlag != CRYP_KEY_WRITE_ENABLE)) {

/* Re-initialize AES IP with proper parameters */
if (HAL_CRYP_DeInit(&ctx->hcryp_aes) != HAL_OK)
return HAL_ERROR;
ctx->hcryp_aes.Init.OperatingMode = opmode;
ctx->hcryp_aes.Init.ChainingMode = CRYP_CHAINMODE_AES_CBC;
ctx->hcryp_aes.Init.KeyWriteFlag = CRYP_KEY_WRITE_ENABLE;
if (HAL_CRYP_Init(&ctx->hcryp_aes) != HAL_OK)
return HAL_ERROR;
}

status = HAL_CRYPEx_AES(&ctx->hcryp_aes, input, length, output, 10);

return status;
}
#endif /* TARGET_STM32L486xG */

int mbedtls_aes_crypt_cbc( mbedtls_aes_context *ctx,
int mode,
Expand All @@ -141,22 +179,24 @@ int mbedtls_aes_crypt_cbc( mbedtls_aes_context *ctx,
const unsigned char *input,
unsigned char *output )
{
int status=0;
int status = 0;
if( length % 16 )
return( MBEDTLS_ERR_AES_INVALID_INPUT_LENGTH );

if( mode == MBEDTLS_AES_DECRYPT )
{
ctx->hcryp_aes.Init.pInitVect = &iv[0]; // used in process, not in the init

status = HAL_CRYP_AESCBC_Decrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10);
#if defined (TARGET_STM32L486xG)
if( mode == MBEDTLS_AES_DECRYPT ) {
status = st_hal_cryp_cbc(ctx, CRYP_ALGOMODE_KEYDERIVATION_DECRYPT, length, iv, (uint8_t *)input, (uint8_t *)output);
} else {
status = st_hal_cryp_cbc(ctx, CRYP_ALGOMODE_ENCRYPT, length, iv, (uint8_t *)input, (uint8_t *)output);
}
else
{
ctx->hcryp_aes.Init.pInitVect = &iv[0]; // used in process, not in the init

#else
ctx->hcryp_aes.Init.pInitVect = &iv[0];

if( mode == MBEDTLS_AES_DECRYPT ) {
status = HAL_CRYP_AESCBC_Decrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10);
} else {
status = HAL_CRYP_AESCBC_Encrypt(&ctx->hcryp_aes, (uint8_t *)input, length, (uint8_t *)output, 10);
}
#endif
return( status );
}
#endif /* MBEDTLS_CIPHER_MODE_CBC */
Expand All @@ -173,10 +213,8 @@ int mbedtls_aes_crypt_cfb128( mbedtls_aes_context *ctx,
int c;
size_t n = *iv_off;

if( mode == MBEDTLS_AES_DECRYPT )
{
while( length-- )
{
if( mode == MBEDTLS_AES_DECRYPT ) {
while( length-- ) {
if( n == 0 )
mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv );

Expand All @@ -186,11 +224,8 @@ int mbedtls_aes_crypt_cfb128( mbedtls_aes_context *ctx,

n = ( n + 1 ) & 0x0F;
}
}
else
{
while( length-- )
{
} else {
while( length-- ) {
if( n == 0 )
mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv );

Expand All @@ -216,8 +251,7 @@ int mbedtls_aes_crypt_cfb8( mbedtls_aes_context *ctx,
unsigned char c;
unsigned char ov[17];

while( length-- )
{
while( length-- ) {
memcpy( ov, iv, 16 );
mbedtls_aes_crypt_ecb( ctx, MBEDTLS_AES_ENCRYPT, iv, iv );

Expand Down
2 changes: 1 addition & 1 deletion targets/targets.json
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1109,7 +1109,7 @@
"core": "Cortex-M4F",
"extra_labels_add": ["STM32L4", "STM32L486RG", "STM32L486xG"],
"detect_code": ["0827"],
"macros_add": ["USBHOST_OTHER"],
"macros_add": ["USBHOST_OTHER", "MBEDTLS_CONFIG_HW_SUPPORT"],
"device_has_add": ["ANALOGOUT", "CAN", "LOWPOWERTIMER", "SERIAL_ASYNCH", "SERIAL_FC", "TRNG", "FLASH"],
"release_versions": ["2", "5"],
"device_name": "STM32L486RG"
Expand Down