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mirror of https://github.com/trezor/trezor-firmware.git synced 2024-12-23 06:48:16 +00:00

fix(legacy): don't erase firmware and storage in intermediate firmware

if the storage has been already initialized
This commit is contained in:
Pavol Rusnak 2021-05-10 17:51:02 +02:00
parent e09a74a79e
commit 0c46b79ebf

View File

@ -20,18 +20,28 @@
#include "trezor.h"
#include <libopencm3/stm32/desig.h>
#include <libopencm3/stm32/flash.h>
#include <string.h>
#include <vendor/libopencm3/include/libopencmsis/core_cm3.h>
#include "bitmaps.h"
#include "bl_check.h"
#include "layout.h"
#include "memory.h"
#include "memzero.h"
#include "norcow_config.h"
#include "oled.h"
#include "rng.h"
#include "setup.h"
#include "timer.h"
#include "util.h"
// legacy storage magic
#define LEGACY_STORAGE_SECTOR 2
static const uint32_t META_MAGIC_V10 = 0x525a5254; // 'TRZR'
// norcow storage magic
static const uint32_t NORCOW_MAGIC = 0x3243524e; // 'NRC2'
static const uint8_t norcow_sectors[NORCOW_SECTOR_COUNT] = NORCOW_SECTORS;
/** Sector erase operation extracted from libopencm3 - flash_erase_sector
* so it can run from RAM
*/
@ -61,22 +71,14 @@ erase_sector(uint8_t sector, uint32_t psize) {
FLASH_CR &= ~(FLASH_CR_SNB_MASK << FLASH_CR_SNB_SHIFT);
}
static void __attribute__((noinline, section(".data")))
erase_firmware_and_storage(void) {
static void __attribute__((noinline, section(".data"))) erase_firmware(void) {
// Flash unlock
FLASH_KEYR = FLASH_KEYR_KEY1;
FLASH_KEYR = FLASH_KEYR_KEY2;
// Erase storage sectors to prevent firmware downgrade to vulnerable version
for (int i = FLASH_STORAGE_SECTOR_FIRST; i <= FLASH_STORAGE_SECTOR_LAST;
i++) {
erase_sector(i, FLASH_CR_PROGRAM_X32);
}
// Erase firmware sectors
for (int i = FLASH_CODE_SECTOR_FIRST; i <= FLASH_CODE_SECTOR_LAST; i++) {
erase_sector(i, FLASH_CR_PROGRAM_X32);
}
// Erase the first firmware sector
// (we don't need full erasure, this speeds up the process)
erase_sector(FLASH_CODE_SECTOR_FIRST, FLASH_CR_PROGRAM_X32);
// Flash lock
FLASH_CR |= FLASH_CR_LOCK;
@ -91,8 +93,8 @@ void __attribute__((noinline, noreturn, section(".data"))) reboot_device(void) {
/** Entry point of RAM shim that deletes old FW, storage and reboot */
void __attribute__((noinline, noreturn, section(".data")))
erase_fw_and_reboot(void) {
erase_firmware_and_storage();
erase_firmware_and_reboot(void) {
erase_firmware();
reboot_device();
for (;;)
@ -114,12 +116,33 @@ int main(void) {
timer_init();
check_and_replace_bootloader(false);
layoutDialog(&bmp_icon_warning, NULL, NULL, NULL, "Erasing old data", NULL,
NULL, "DO NOT UNPLUG", "YOUR TREZOR!", NULL);
oledRefresh();
secbool storage_initialized = secfalse;
// from this point the execution is from RAM instead of flash
erase_fw_and_reboot();
// check legacy storage
uint32_t *magic = (uint32_t *)flash_get_address(LEGACY_STORAGE_SECTOR, 0,
sizeof(META_MAGIC_V10));
if (*magic == META_MAGIC_V10) {
storage_initialized = sectrue;
}
if (storage_initialized == secfalse) {
// check norcow storage
for (uint8_t i = 0; i < NORCOW_SECTOR_COUNT; i++) {
magic = (uint32_t *)flash_get_address(norcow_sectors[i], 0,
sizeof(NORCOW_MAGIC));
if (*magic == NORCOW_MAGIC) {
storage_initialized = sectrue;
break;
}
}
}
if (sectrue == storage_initialized) {
// don't erase
reboot_device();
} else {
erase_firmware_and_reboot();
}
return 0;
}