5b9b5d9636
In commit 309376f51a, it seems like regression
was added to use ROM level API for disabling flash write protection. This
started random firmware crashes (on specific modules) with exception
`IllegalInstruction` during encrypted flash writes.
Fix here removes relevant ROM API call, since disabling flash write protection
is already ensured by caller of this API.
Closes https://github.com/espressif/esp-idf/issues/5467
86 lines
3.1 KiB
C
86 lines
3.1 KiB
C
// Copyright 2018 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.
|
|
#include <string.h>
|
|
#include "esp_spi_flash.h"
|
|
#include "esp32/rom/spi_flash.h"
|
|
#include "esp32/rom/cache.h"
|
|
|
|
static inline void IRAM_ATTR spi_flash_guard_start(void)
|
|
{
|
|
const spi_flash_guard_funcs_t *ops = spi_flash_guard_get();
|
|
if (ops && ops->start) {
|
|
ops->start();
|
|
}
|
|
}
|
|
|
|
static inline void IRAM_ATTR spi_flash_guard_end(void)
|
|
{
|
|
const spi_flash_guard_funcs_t *ops = spi_flash_guard_get();
|
|
if (ops && ops->end) {
|
|
ops->end();
|
|
}
|
|
}
|
|
|
|
esp_rom_spiflash_result_t IRAM_ATTR spi_flash_write_encrypted_chip(size_t dest_addr, const void *src, size_t size)
|
|
{
|
|
const uint8_t *ssrc = (const uint8_t *)src;
|
|
esp_rom_spiflash_result_t rc = ESP_ROM_SPIFLASH_RESULT_OK;
|
|
|
|
assert((dest_addr % 16) == 0);
|
|
assert((size % 16) == 0);
|
|
|
|
/* esp_rom_spiflash_write_encrypted encrypts data in RAM as it writes,
|
|
so copy to a temporary buffer - 32 bytes at a time.
|
|
|
|
Each call to esp_rom_spiflash_write_encrypted takes a 32 byte "row" of
|
|
data to encrypt, and each row is two 16 byte AES blocks
|
|
that share a key (as derived from flash address).
|
|
*/
|
|
uint8_t encrypt_buf[32] __attribute__((aligned(4)));
|
|
uint32_t row_size;
|
|
for (size_t i = 0; i < size; i += row_size) {
|
|
uint32_t row_addr = dest_addr + i;
|
|
if (i == 0 && (row_addr % 32) != 0) {
|
|
/* writing to second block of a 32 byte row */
|
|
row_size = 16;
|
|
row_addr -= 16;
|
|
/* copy to second block in buffer */
|
|
memcpy(encrypt_buf + 16, ssrc + i, 16);
|
|
/* decrypt the first block from flash, will reencrypt to same bytes */
|
|
spi_flash_read_encrypted(row_addr, encrypt_buf, 16);
|
|
} else if (size - i == 16) {
|
|
/* 16 bytes left, is first block of a 32 byte row */
|
|
row_size = 16;
|
|
/* copy to first block in buffer */
|
|
memcpy(encrypt_buf, ssrc + i, 16);
|
|
/* decrypt the second block from flash, will reencrypt to same bytes */
|
|
spi_flash_read_encrypted(row_addr + 16, encrypt_buf + 16, 16);
|
|
} else {
|
|
/* Writing a full 32 byte row (2 blocks) */
|
|
row_size = 32;
|
|
memcpy(encrypt_buf, ssrc + i, 32);
|
|
}
|
|
|
|
spi_flash_guard_start();
|
|
rc = esp_rom_spiflash_write_encrypted(row_addr, (uint32_t *)encrypt_buf, 32);
|
|
spi_flash_guard_end();
|
|
if (rc != ESP_ROM_SPIFLASH_RESULT_OK) {
|
|
break;
|
|
}
|
|
}
|
|
bzero(encrypt_buf, sizeof(encrypt_buf));
|
|
|
|
return rc;
|
|
}
|
|
|