mirror
/
esp-idf
kopia lustrzana https://github.com/espressif/esp-idf
1
0
Forkuj 0
Kod Zgłoszenia Projekty Wydania Wiki Aktywność
esp-idf/components/esp_hw_support/esp_hmac.c

295 wiersze
8.6 KiB
C
Czysty Wina Historia

/*
* SPDX-FileCopyrightText: 2015-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <string.h>
#include "rom/efuse.h"
#include "rom/hmac.h"
#include "rom/ets_sys.h"
#include "esp_efuse.h"
#include "esp_efuse_table.h"
#include "esp_hmac.h"
#include "esp_log.h"
#include "esp_crypto_lock.h"
#include "esp_private/esp_crypto_lock_internal.h"
#include "soc/hwcrypto_reg.h"
#include "soc/system_reg.h"
#if !CONFIG_IDF_TARGET_ESP32S2
#include "hal/ds_ll.h"
#include "hal/hmac_hal.h"
#include "hal/hmac_ll.h"
#include "esp_private/periph_ctrl.h"
#endif
#define SHA256_BLOCK_SZ 64
#define SHA256_PAD_SZ 8
#if defined(CONFIG_IDF_TARGET_ESP32S3) || defined(CONFIG_IDF_TARGET_ESP32S2)
#define JTAG_STATUS_BIT ESP_EFUSE_HARD_DIS_JTAG
#else
/* For ESP32C3, ESP32C6, ESP32H2, ESP32P4 */
#define JTAG_STATUS_BIT ESP_EFUSE_DIS_PAD_JTAG
#endif
static const char *TAG = "esp_hmac";
#if !CONFIG_IDF_TARGET_ESP32S2
/**
* @brief Apply the HMAC padding without the embedded length.
*
* @note This function does not check the data length, it is the responsibility of the other functions in this
* module to make sure that \c data_len is at most SHA256_BLOCK_SZ - 1 so the padding fits in.
* Otherwise, this function has undefined behavior.
* Note however, that for the actual HMAC implementation, the length also needs to be applied at the end
* of the block. This function alone deosn't do that.
*/
static void write_and_padd(uint8_t *block, const uint8_t *data, uint16_t data_len)
{
memcpy(block, data, data_len);
// Apply a one bit, followed by zero bits (refer to the TRM of respective target).
block[data_len] = 0x80;
bzero(block + data_len + 1, SHA256_BLOCK_SZ - data_len - 1);
}
esp_err_t esp_hmac_calculate(hmac_key_id_t key_id,
const void *message,
size_t message_len,
uint8_t *hmac)
{
const uint8_t *message_bytes = (const uint8_t *)message;
if (!message || !hmac) {
return ESP_ERR_INVALID_ARG;
}
if (key_id >= HMAC_KEY_MAX) {
return ESP_ERR_INVALID_ARG;
}
esp_crypto_hmac_lock_acquire();
// We also enable SHA and DS here. SHA is used by HMAC, DS will otherwise hold SHA in reset state.
HMAC_RCC_ATOMIC() {
hmac_ll_enable_bus_clock(true);
hmac_ll_reset_register();
}
periph_module_enable(PERIPH_SHA_MODULE);
DS_RCC_ATOMIC() {
ds_ll_enable_bus_clock(true);
ds_ll_reset_register();
}
hmac_hal_start();
uint32_t conf_error = hmac_hal_configure(HMAC_OUTPUT_USER, key_id);
if (conf_error) {
esp_crypto_hmac_lock_release();
return ESP_FAIL;
}
if (message_len + 1 + SHA256_PAD_SZ <= SHA256_BLOCK_SZ) {
// If message including padding is only one block...
// Last message block, so apply SHA-256 padding rules in software
uint8_t block[SHA256_BLOCK_SZ];
uint64_t bit_len = __builtin_bswap64(message_len * 8 + 512);
write_and_padd(block, message_bytes, message_len);
// Final block: append the bit length in this block and signal padding to peripheral
memcpy(block + SHA256_BLOCK_SZ - sizeof(bit_len),
&bit_len, sizeof(bit_len));
hmac_hal_write_one_block_512(block);
} else {
// If message including padding is needs more than one block
// write all blocks without padding except the last one
size_t remaining_blocks = message_len / SHA256_BLOCK_SZ;
for (int i = 1; i < remaining_blocks; i++) {
hmac_hal_write_block_512(message_bytes);
message_bytes += SHA256_BLOCK_SZ;
hmac_hal_next_block_normal();
}
// If message fits into one block but without padding, we must not write another block.
if (remaining_blocks) {
hmac_hal_write_block_512(message_bytes);
message_bytes += SHA256_BLOCK_SZ;
}
size_t remaining = message_len % SHA256_BLOCK_SZ;
// Last message block, so apply SHA-256 padding rules in software
uint8_t block[SHA256_BLOCK_SZ];
uint64_t bit_len = __builtin_bswap64(message_len * 8 + 512);
// If the remaining message and appended padding doesn't fit into a single block, we have to write an
// extra block with the rest of the message and potential padding first.
if (remaining >= SHA256_BLOCK_SZ - SHA256_PAD_SZ) {
write_and_padd(block, message_bytes, remaining);
hmac_hal_next_block_normal();
hmac_hal_write_block_512(block);
bzero(block, SHA256_BLOCK_SZ);
} else {
write_and_padd(block, message_bytes, remaining);
}
memcpy(block + SHA256_BLOCK_SZ - sizeof(bit_len),
&bit_len, sizeof(bit_len));
hmac_hal_next_block_padding();
hmac_hal_write_block_512(block);
}
// Read back result (bit swapped)
hmac_hal_read_result_256(hmac);
DS_RCC_ATOMIC() {
ds_ll_enable_bus_clock(false);
}
periph_module_disable(PERIPH_SHA_MODULE);
HMAC_RCC_ATOMIC() {
hmac_ll_enable_bus_clock(false);
}
esp_crypto_hmac_lock_release();
return ESP_OK;
}
static ets_efuse_block_t convert_key_type(hmac_key_id_t key_id) {
return ETS_EFUSE_BLOCK_KEY0 + (ets_efuse_block_t) key_id;
}
esp_err_t esp_hmac_jtag_enable(hmac_key_id_t key_id, const uint8_t *token)
{
int ets_status;
esp_err_t err = ESP_OK;
if ((!token) || (key_id >= HMAC_KEY_MAX))
return ESP_ERR_INVALID_ARG;
/* Check if JTAG is permanently disabled by HW Disable eFuse */
if (esp_efuse_read_field_bit(JTAG_STATUS_BIT)) {
ESP_LOGE(TAG, "JTAG disabled permanently.");
return ESP_FAIL;
}
esp_crypto_hmac_lock_acquire();
ets_status = ets_jtag_enable_temporarily(token, convert_key_type(key_id));
if (ets_status != ETS_OK) {
// ets_jtag_enable_temporarily returns either ETS_OK or ETS_FAIL
err = ESP_FAIL;
ESP_LOGE(TAG, "JTAG re-enabling failed (%d)", err);
}
ESP_LOGD(TAG, "HMAC computation in downstream mode is completed.");
ets_hmac_disable();
esp_crypto_hmac_lock_release();
return err;
}
esp_err_t esp_hmac_jtag_disable()
{
esp_crypto_hmac_lock_acquire();
ets_hmac_enable();
REG_WRITE(HMAC_SET_INVALIDATE_JTAG_REG, 1);
ets_hmac_disable();
esp_crypto_hmac_lock_release();
ESP_LOGD(TAG, "Invalidate JTAG result register. JTAG disabled.");
return ESP_OK;
}
#else /* !CONFIG_IDF_TARGET_ESP32S2 */
static ets_efuse_block_t convert_key_type(hmac_key_id_t key_id) {
return ETS_EFUSE_BLOCK_KEY0 + (ets_efuse_block_t) key_id;
}
esp_err_t esp_hmac_calculate(hmac_key_id_t key_id,
const void *message,
size_t message_len,
uint8_t *hmac)
{
int hmac_ret;
if (!message || !hmac) return ESP_ERR_INVALID_ARG;
if (key_id >= HMAC_KEY_MAX) return ESP_ERR_INVALID_ARG;
esp_crypto_dma_lock_acquire();
ets_hmac_enable();
hmac_ret = ets_hmac_calculate_message(convert_key_type(key_id), message, message_len, hmac);
ets_hmac_disable();
esp_crypto_dma_lock_release();
if (hmac_ret != 0) {
return ESP_FAIL;
} else {
return ESP_OK;
}
}
esp_err_t esp_hmac_jtag_enable(hmac_key_id_t key_id, const uint8_t *token)
{
int ets_status;
esp_err_t err = ESP_OK;
if ((!token) || (key_id >= HMAC_KEY_MAX))
return ESP_ERR_INVALID_ARG;
/* Check if JTAG is permanently disabled by HW Disable eFuse */
if (esp_efuse_read_field_bit(ESP_EFUSE_HARD_DIS_JTAG)) {
ESP_LOGE(TAG, "JTAG disabled permanently.");
return ESP_FAIL;
}
esp_crypto_dma_lock_acquire();
ets_hmac_enable();
/* Token updating into HMAC module. */
for (int i = 0; i < 32; i += 4) {
uint32_t key_word;
memcpy(&key_word, &token[i], 4);
REG_WRITE(DPORT_JTAG_CTRL_0_REG + i, __builtin_bswap32(key_word));
}
ets_status = ets_hmac_calculate_downstream(convert_key_type(key_id), ETS_EFUSE_KEY_PURPOSE_HMAC_DOWN_JTAG);
if (ets_status != ETS_OK) {
err = ESP_FAIL;
ESP_LOGE(TAG, "HMAC downstream JTAG enable mode setting failed. (%d)", err);
}
ESP_LOGD(TAG, "HMAC computation in downstream mode is completed.");
ets_hmac_disable();
esp_crypto_dma_lock_release();
return err;
}
esp_err_t esp_hmac_jtag_disable()
{
esp_crypto_dma_lock_acquire();
ets_hmac_enable();
REG_WRITE(HMAC_SET_INVALIDATE_JTAG_REG, 1);
ets_hmac_disable();
esp_crypto_dma_lock_release();
ESP_LOGD(TAG, "Invalidate JTAG result register. JTAG disabled.");
return ESP_OK;
}
#endif /* CONFIG_IDF_TARGET_ESP32S2*/
Reference in New Issue View Git Blame Kopiuj bezpośredni odnośnik