mcuboot/boot/zephyr/single_loader.c

132 lines
3.2 KiB
C

/*
* SPDX-License-Identifier: Apache-2.0
*
* Copyright (c) 2020 Nordic Semiconductor ASA
* Copyright (c) 2020 Arm Limited
*/
#include <assert.h>
#include "bootutil/image.h"
#include "bootutil_priv.h"
#include "bootutil/bootutil_log.h"
#include "bootutil/fault_injection_hardening.h"
#include "mcuboot_config/mcuboot_config.h"
BOOT_LOG_MODULE_DECLARE(mcuboot);
/* Variables passed outside of unit via poiters. */
static const struct flash_area *_fa_p;
static struct image_header _hdr = { 0 };
#ifdef MCUBOOT_VALIDATE_PRIMARY_SLOT
/**
* Validate hash of a primary boot image.
*
* @param[in] fa_p flash area pointer
* @param[in] hdr boot image header pointer
*
* @return FIH_SUCCESS on success, error code otherwise
*/
inline static fih_int
boot_image_validate(const struct flash_area *fa_p,
struct image_header *hdr)
{
static uint8_t tmpbuf[BOOT_TMPBUF_SZ];
fih_int fih_rc = FIH_FAILURE;
/* NOTE: The first argument to boot_image_validate, for enc_state pointer,
* is allowed to be NULL only because the single image loader compiles
* with BOOT_IMAGE_NUMBER == 1, which excludes the code that uses
* the pointer from compilation.
*/
/* Validate hash */
FIH_CALL(bootutil_img_validate, fih_rc, NULL, 0, hdr, fa_p, tmpbuf,
BOOT_TMPBUF_SZ, NULL, 0, NULL);
FIH_RET(fih_rc);
}
#endif /* MCUBOOT_VALIDATE_PRIMARY_SLOT */
/**
* Attempts to load image header from flash; verifies flash header fields.
*
* @param[in] fa_p flash area pointer
* @param[out] hdr buffer for image header
*
* @return 0 on success, error code otherwise
*/
static int
boot_image_load_header(const struct flash_area *fa_p,
struct image_header *hdr)
{
uint32_t size;
int rc = flash_area_read(fa_p, 0, hdr, sizeof *hdr);
if (rc != 0) {
rc = BOOT_EFLASH;
BOOT_LOG_ERR("Failed reading image header");
return BOOT_EFLASH;
}
if (hdr->ih_magic != IMAGE_MAGIC) {
BOOT_LOG_ERR("Bad image magic 0x%lx", (unsigned long)hdr->ih_magic);
return BOOT_EBADIMAGE;
}
if (hdr->ih_flags & IMAGE_F_NON_BOOTABLE) {
BOOT_LOG_ERR("Image not bootable");
return BOOT_EBADIMAGE;
}
if (!boot_u32_safe_add(&size, hdr->ih_img_size, hdr->ih_hdr_size) ||
size >= flash_area_get_size(fa_p)) {
return BOOT_EBADIMAGE;
}
return 0;
}
/**
* Gather information on image and prepare for booting.
*
* @parami[out] rsp Parameters for booting image, on success
*
* @return FIH_SUCCESS on success; nonzero on failure.
*/
fih_int
boot_go(struct boot_rsp *rsp)
{
int rc = -1;
fih_int fih_rc = FIH_FAILURE;
rc = flash_area_open(FLASH_AREA_IMAGE_PRIMARY(0), &_fa_p);
assert(rc == 0);
rc = boot_image_load_header(_fa_p, &_hdr);
if (rc != 0)
goto out;
#ifdef MCUBOOT_VALIDATE_PRIMARY_SLOT
FIH_CALL(boot_image_validate, fih_rc, _fa_p, &_hdr);
if (fih_not_eq(fih_rc, FIH_SUCCESS)) {
goto out;
}
#else
fih_rc = FIH_SUCCESS;
#endif /* MCUBOOT_VALIDATE_PRIMARY_SLOT */
rsp->br_flash_dev_id = flash_area_get_device_id(_fa_p);
rsp->br_image_off = flash_area_get_off(_fa_p);
rsp->br_hdr = &_hdr;
out:
flash_area_close(_fa_p);
FIH_RET(fih_rc);
}