| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| |
| /** |
| * This file provides an interface to the boot loader. Functions defined in |
| * this file should only be called while the boot loader is running. |
| */ |
| |
| #include <assert.h> |
| #include <stddef.h> |
| #include <stdbool.h> |
| #include <inttypes.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <hal/hal_flash.h> |
| #include <os/os_malloc.h> |
| #include "bootutil/bootutil.h" |
| #include "bootutil/image.h" |
| #include "bootutil_priv.h" |
| |
| #define BOOT_LOG_LEVEL BOOT_LOG_LEVEL_INFO |
| #include "bootutil/bootutil_log.h" |
| |
| #ifdef MCUBOOT_MYNEWT |
| #include "mcuboot_config/mcuboot_config.h" |
| #endif |
| |
| static struct boot_loader_state boot_data; |
| |
| struct boot_status_table { |
| /** |
| * For each field, a value of 0 means "any". |
| */ |
| uint8_t bst_magic_slot0; |
| uint8_t bst_magic_scratch; |
| uint8_t bst_copy_done_slot0; |
| uint8_t bst_status_source; |
| }; |
| |
| /** |
| * This set of tables maps swap state contents to boot status location. |
| * When searching for a match, these tables must be iterated in order. |
| */ |
| static const struct boot_status_table boot_status_tables[] = { |
| { |
| /* | slot-0 | scratch | |
| * ----------+------------+------------| |
| * magic | Good | Any | |
| * copy-done | 0x01 | N/A | |
| * ----------+------------+------------' |
| * source: none | |
| * ------------------------------------' |
| */ |
| .bst_magic_slot0 = BOOT_MAGIC_GOOD, |
| .bst_magic_scratch = 0, |
| .bst_copy_done_slot0 = 0x01, |
| .bst_status_source = BOOT_STATUS_SOURCE_NONE, |
| }, |
| |
| { |
| /* | slot-0 | scratch | |
| * ----------+------------+------------| |
| * magic | Good | Any | |
| * copy-done | 0xff | N/A | |
| * ----------+------------+------------' |
| * source: slot 0 | |
| * ------------------------------------' |
| */ |
| .bst_magic_slot0 = BOOT_MAGIC_GOOD, |
| .bst_magic_scratch = 0, |
| .bst_copy_done_slot0 = 0xff, |
| .bst_status_source = BOOT_STATUS_SOURCE_SLOT0, |
| }, |
| |
| { |
| /* | slot-0 | scratch | |
| * ----------+------------+------------| |
| * magic | Any | Good | |
| * copy-done | Any | N/A | |
| * ----------+------------+------------' |
| * source: scratch | |
| * ------------------------------------' |
| */ |
| .bst_magic_slot0 = 0, |
| .bst_magic_scratch = BOOT_MAGIC_GOOD, |
| .bst_copy_done_slot0 = 0, |
| .bst_status_source = BOOT_STATUS_SOURCE_SCRATCH, |
| }, |
| |
| { |
| /* | slot-0 | scratch | |
| * ----------+------------+------------| |
| * magic | Unset | Any | |
| * copy-done | 0xff | N/A | |
| * ----------+------------+------------| |
| * source: varies | |
| * ------------------------------------+------------------------------+ |
| * This represents one of two cases: | |
| * o No swaps ever (no status to read, so no harm in checking). | |
| * o Mid-revert; status in slot 0. | |
| * -------------------------------------------------------------------' |
| */ |
| .bst_magic_slot0 = BOOT_MAGIC_UNSET, |
| .bst_magic_scratch = 0, |
| .bst_copy_done_slot0 = 0xff, |
| .bst_status_source = BOOT_STATUS_SOURCE_SLOT0, |
| }, |
| }; |
| |
| #define BOOT_STATUS_TABLES_COUNT \ |
| (sizeof boot_status_tables / sizeof boot_status_tables[0]) |
| |
| #define BOOT_LOG_SWAP_STATE(area, state) \ |
| BOOT_LOG_INF("%s: magic=%s, copy_done=0x%x, image_ok=0x%x", \ |
| (area), \ |
| ((state)->magic == BOOT_MAGIC_GOOD ? "good" : \ |
| (state)->magic == BOOT_MAGIC_UNSET ? "unset" : \ |
| "bad"), \ |
| (state)->copy_done, \ |
| (state)->image_ok) |
| |
| /** |
| * Determines where in flash the most recent boot status is stored. The boot |
| * status is necessary for completing a swap that was interrupted by a boot |
| * loader reset. |
| * |
| * @return A BOOT_STATUS_SOURCE_[...] code indicating where * status should be read from. |
| */ |
| static int |
| boot_status_source(void) |
| { |
| const struct boot_status_table *table; |
| struct boot_swap_state state_scratch; |
| struct boot_swap_state state_slot0; |
| int rc; |
| int i; |
| uint8_t source; |
| |
| rc = boot_read_swap_state_by_id(FLASH_AREA_IMAGE_0, &state_slot0); |
| assert(rc == 0); |
| |
| rc = boot_read_swap_state_by_id(FLASH_AREA_IMAGE_SCRATCH, &state_scratch); |
| assert(rc == 0); |
| |
| BOOT_LOG_SWAP_STATE("Image 0", &state_slot0); |
| BOOT_LOG_SWAP_STATE("Scratch", &state_scratch); |
| |
| for (i = 0; i < BOOT_STATUS_TABLES_COUNT; i++) { |
| table = &boot_status_tables[i]; |
| |
| if ((table->bst_magic_slot0 == 0 || |
| table->bst_magic_slot0 == state_slot0.magic) && |
| (table->bst_magic_scratch == 0 || |
| table->bst_magic_scratch == state_scratch.magic) && |
| (table->bst_copy_done_slot0 == 0 || |
| table->bst_copy_done_slot0 == state_slot0.copy_done)) { |
| source = table->bst_status_source; |
| BOOT_LOG_INF("Boot source: %s", |
| source == BOOT_STATUS_SOURCE_NONE ? "none" : |
| source == BOOT_STATUS_SOURCE_SCRATCH ? "scratch" : |
| source == BOOT_STATUS_SOURCE_SLOT0 ? "slot 0" : |
| "BUG; can't happen"); |
| return source; |
| } |
| } |
| |
| BOOT_LOG_INF("Boot source: none"); |
| return BOOT_STATUS_SOURCE_NONE; |
| } |
| |
| /** |
| * Calculates the type of swap that just completed. |
| * |
| * This is used when a swap is interrupted by an external event. After |
| * finishing the swap operation determines what the initial request was. |
| */ |
| static int |
| boot_previous_swap_type(void) |
| { |
| int post_swap_type; |
| |
| post_swap_type = boot_swap_type(); |
| |
| switch (post_swap_type) { |
| case BOOT_SWAP_TYPE_NONE : return BOOT_SWAP_TYPE_PERM; |
| case BOOT_SWAP_TYPE_REVERT : return BOOT_SWAP_TYPE_TEST; |
| case BOOT_SWAP_TYPE_PANIC : return BOOT_SWAP_TYPE_PANIC; |
| } |
| |
| return BOOT_SWAP_TYPE_FAIL; |
| } |
| |
| /* |
| * Compute the total size of the given image. Includes the size of |
| * the TLVs. |
| */ |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static int |
| boot_read_image_size(int slot, struct image_header *hdr, uint32_t *size) |
| { |
| const struct flash_area *fap; |
| struct image_tlv_info info; |
| int area_id; |
| int rc; |
| |
| area_id = flash_area_id_from_image_slot(slot); |
| rc = flash_area_open(area_id, &fap); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = flash_area_read(fap, hdr->ih_hdr_size + hdr->ih_img_size, |
| &info, sizeof(info)); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| if (info.it_magic != IMAGE_TLV_INFO_MAGIC) { |
| rc = BOOT_EBADIMAGE; |
| goto done; |
| } |
| *size = hdr->ih_hdr_size + hdr->ih_img_size + info.it_tlv_tot; |
| rc = 0; |
| |
| done: |
| flash_area_close(fap); |
| return rc; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| |
| static int |
| boot_read_image_header(int slot, struct image_header *out_hdr) |
| { |
| const struct flash_area *fap; |
| int area_id; |
| int rc; |
| |
| area_id = flash_area_id_from_image_slot(slot); |
| rc = flash_area_open(area_id, &fap); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = flash_area_read(fap, 0, out_hdr, sizeof *out_hdr); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = 0; |
| |
| done: |
| flash_area_close(fap); |
| return rc; |
| } |
| |
| static int |
| boot_read_image_headers(void) |
| { |
| int rc; |
| int i; |
| |
| for (i = 0; i < BOOT_NUM_SLOTS; i++) { |
| rc = boot_read_image_header(i, boot_img_hdr(&boot_data, i)); |
| if (rc != 0) { |
| /* If at least the first slot's header was read successfully, then |
| * the boot loader can attempt a boot. Failure to read any headers |
| * is a fatal error. |
| */ |
| if (i > 0) { |
| return 0; |
| } else { |
| return rc; |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| static uint8_t |
| boot_write_sz(void) |
| { |
| uint8_t elem_sz; |
| uint8_t align; |
| |
| /* Figure out what size to write update status update as. The size depends |
| * on what the minimum write size is for scratch area, active image slot. |
| * We need to use the bigger of those 2 values. |
| */ |
| elem_sz = hal_flash_align(boot_img_fa_device_id(&boot_data, 0)); |
| align = hal_flash_align(boot_scratch_fa_device_id(&boot_data)); |
| if (align > elem_sz) { |
| elem_sz = align; |
| } |
| |
| return elem_sz; |
| } |
| |
| static int |
| boot_slots_compatible(void) |
| { |
| size_t num_sectors_0 = boot_img_num_sectors(&boot_data, 0); |
| size_t num_sectors_1 = boot_img_num_sectors(&boot_data, 1); |
| size_t size_0, size_1; |
| size_t i; |
| |
| /* Ensure both image slots have identical sector layouts. */ |
| if (num_sectors_0 != num_sectors_1) { |
| return 0; |
| } |
| for (i = 0; i < num_sectors_0; i++) { |
| size_0 = boot_img_sector_size(&boot_data, 0, i); |
| size_1 = boot_img_sector_size(&boot_data, 1, i); |
| if (size_0 != size_1) { |
| return 0; |
| } |
| } |
| |
| return 1; |
| } |
| |
| /** |
| * Determines the sector layout of both image slots and the scratch area. |
| * This information is necessary for calculating the number of bytes to erase |
| * and copy during an image swap. The information collected during this |
| * function is used to populate the boot_data global. |
| */ |
| static int |
| boot_read_sectors(void) |
| { |
| int rc; |
| |
| rc = boot_initialize_area(&boot_data, FLASH_AREA_IMAGE_0); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| rc = boot_initialize_area(&boot_data, FLASH_AREA_IMAGE_1); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| BOOT_WRITE_SZ(&boot_data) = boot_write_sz(); |
| |
| return 0; |
| } |
| |
| static uint32_t |
| boot_status_internal_off(int idx, int state, int elem_sz) |
| { |
| int idx_sz; |
| |
| idx_sz = elem_sz * BOOT_STATUS_STATE_COUNT; |
| |
| return idx * idx_sz + state * elem_sz; |
| } |
| |
| /** |
| * Reads the status of a partially-completed swap, if any. This is necessary |
| * to recover in case the boot lodaer was reset in the middle of a swap |
| * operation. |
| */ |
| static int |
| boot_read_status_bytes(const struct flash_area *fap, struct boot_status *bs) |
| { |
| uint32_t off; |
| uint8_t status; |
| int max_entries; |
| int found; |
| int rc; |
| int i; |
| |
| off = boot_status_off(fap); |
| max_entries = boot_status_entries(fap); |
| |
| found = 0; |
| for (i = 0; i < max_entries; i++) { |
| rc = flash_area_read(fap, off + i * BOOT_WRITE_SZ(&boot_data), |
| &status, 1); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| if (status == 0xff) { |
| if (found) { |
| break; |
| } |
| } else if (!found) { |
| found = 1; |
| } |
| } |
| |
| if (found) { |
| i--; |
| bs->idx = i / BOOT_STATUS_STATE_COUNT; |
| bs->state = i % BOOT_STATUS_STATE_COUNT; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * Reads the boot status from the flash. The boot status contains |
| * the current state of an interrupted image copy operation. If the boot |
| * status is not present, or it indicates that previous copy finished, |
| * there is no operation in progress. |
| */ |
| static int |
| boot_read_status(struct boot_status *bs) |
| { |
| const struct flash_area *fap; |
| int status_loc; |
| int area_id; |
| int rc; |
| |
| memset(bs, 0, sizeof *bs); |
| |
| status_loc = boot_status_source(); |
| switch (status_loc) { |
| case BOOT_STATUS_SOURCE_NONE: |
| return 0; |
| |
| case BOOT_STATUS_SOURCE_SCRATCH: |
| area_id = FLASH_AREA_IMAGE_SCRATCH; |
| break; |
| |
| case BOOT_STATUS_SOURCE_SLOT0: |
| area_id = FLASH_AREA_IMAGE_0; |
| break; |
| |
| default: |
| assert(0); |
| return BOOT_EBADARGS; |
| } |
| |
| rc = flash_area_open(area_id, &fap); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| rc = boot_read_status_bytes(fap, bs); |
| |
| flash_area_close(fap); |
| return rc; |
| } |
| |
| /** |
| * Writes the supplied boot status to the flash file system. The boot status |
| * contains the current state of an in-progress image copy operation. |
| * |
| * @param bs The boot status to write. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| int |
| boot_write_status(struct boot_status *bs) |
| { |
| const struct flash_area *fap; |
| uint32_t off; |
| int area_id; |
| int rc; |
| uint8_t buf[BOOT_MAX_ALIGN]; |
| uint8_t align; |
| |
| /* NOTE: The first sector copied (that is the last sector on slot) contains |
| * the trailer. Since in the last step SLOT 0 is erased, the first |
| * two status writes go to the scratch which will be copied to SLOT 0! |
| */ |
| |
| if (bs->use_scratch) { |
| /* Write to scratch. */ |
| area_id = FLASH_AREA_IMAGE_SCRATCH; |
| } else { |
| /* Write to slot 0. */ |
| area_id = FLASH_AREA_IMAGE_0; |
| } |
| |
| rc = flash_area_open(area_id, &fap); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| off = boot_status_off(fap) + |
| boot_status_internal_off(bs->idx, bs->state, |
| BOOT_WRITE_SZ(&boot_data)); |
| |
| align = hal_flash_align(fap->fa_device_id); |
| memset(buf, 0xFF, BOOT_MAX_ALIGN); |
| buf[0] = bs->state; |
| |
| rc = flash_area_write(fap, off, buf, align); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = 0; |
| |
| done: |
| flash_area_close(fap); |
| return rc; |
| } |
| |
| /* |
| * Validate image hash/signature in a slot. |
| */ |
| static int |
| boot_image_check(struct image_header *hdr, const struct flash_area *fap) |
| { |
| static uint8_t tmpbuf[BOOT_TMPBUF_SZ]; |
| |
| if (bootutil_img_validate(hdr, fap, tmpbuf, BOOT_TMPBUF_SZ, |
| NULL, 0, NULL)) { |
| return BOOT_EBADIMAGE; |
| } |
| return 0; |
| } |
| |
| static int |
| split_image_check(struct image_header *app_hdr, |
| const struct flash_area *app_fap, |
| struct image_header *loader_hdr, |
| const struct flash_area *loader_fap) |
| { |
| static void *tmpbuf; |
| uint8_t loader_hash[32]; |
| |
| if (!tmpbuf) { |
| tmpbuf = malloc(BOOT_TMPBUF_SZ); |
| if (!tmpbuf) { |
| return BOOT_ENOMEM; |
| } |
| } |
| |
| if (bootutil_img_validate(loader_hdr, loader_fap, tmpbuf, BOOT_TMPBUF_SZ, |
| NULL, 0, loader_hash)) { |
| return BOOT_EBADIMAGE; |
| } |
| |
| if (bootutil_img_validate(app_hdr, app_fap, tmpbuf, BOOT_TMPBUF_SZ, |
| loader_hash, 32, NULL)) { |
| return BOOT_EBADIMAGE; |
| } |
| |
| return 0; |
| } |
| |
| static int |
| boot_validate_slot(int slot) |
| { |
| const struct flash_area *fap; |
| struct image_header *hdr; |
| int rc; |
| |
| hdr = boot_img_hdr(&boot_data, slot); |
| if (hdr->ih_magic == 0xffffffff || hdr->ih_flags & IMAGE_F_NON_BOOTABLE) { |
| /* No bootable image in slot; continue booting from slot 0. */ |
| return -1; |
| } |
| |
| rc = flash_area_open(flash_area_id_from_image_slot(slot), &fap); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| if ((hdr->ih_magic != IMAGE_MAGIC || boot_image_check(hdr, fap) != 0)) { |
| if (slot != 0) { |
| flash_area_erase(fap, 0, fap->fa_size); |
| /* Image in slot 1 is invalid. Erase the image and |
| * continue booting from slot 0. |
| */ |
| } |
| BOOT_LOG_ERR("Image in slot %d is not valid!", slot); |
| return -1; |
| } |
| |
| flash_area_close(fap); |
| |
| /* Image in slot 1 is valid. */ |
| return 0; |
| } |
| |
| /** |
| * Determines which swap operation to perform, if any. If it is determined |
| * that a swap operation is required, the image in the second slot is checked |
| * for validity. If the image in the second slot is invalid, it is erased, and |
| * a swap type of "none" is indicated. |
| * |
| * @return The type of swap to perform (BOOT_SWAP_TYPE...) |
| */ |
| static int |
| boot_validated_swap_type(void) |
| { |
| int swap_type; |
| |
| swap_type = boot_swap_type(); |
| switch (swap_type) { |
| case BOOT_SWAP_TYPE_TEST: |
| case BOOT_SWAP_TYPE_PERM: |
| case BOOT_SWAP_TYPE_REVERT: |
| /* Boot loader wants to switch to slot 1. Ensure image is valid. */ |
| if (boot_validate_slot(1) != 0) { |
| swap_type = BOOT_SWAP_TYPE_FAIL; |
| } |
| } |
| |
| return swap_type; |
| } |
| |
| /** |
| * Calculates the number of sectors the scratch area can contain. A "last" |
| * source sector is specified because images are copied backwards in flash |
| * (final index to index number 0). |
| * |
| * @param last_sector_idx The index of the last source sector |
| * (inclusive). |
| * @param out_first_sector_idx The index of the first source sector |
| * (inclusive) gets written here. |
| * |
| * @return The number of bytes comprised by the |
| * [first-sector, last-sector] range. |
| */ |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static uint32_t |
| boot_copy_sz(int last_sector_idx, int *out_first_sector_idx) |
| { |
| size_t scratch_sz; |
| uint32_t new_sz; |
| uint32_t sz; |
| int i; |
| |
| sz = 0; |
| |
| scratch_sz = boot_scratch_area_size(&boot_data); |
| for (i = last_sector_idx; i >= 0; i--) { |
| new_sz = sz + boot_img_sector_size(&boot_data, 0, i); |
| if (new_sz > scratch_sz) { |
| break; |
| } |
| sz = new_sz; |
| } |
| |
| /* i currently refers to a sector that doesn't fit or it is -1 because all |
| * sectors have been processed. In both cases, exclude sector i. |
| */ |
| *out_first_sector_idx = i + 1; |
| return sz; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| |
| /** |
| * Erases a region of flash. |
| * |
| * @param flash_area_idx The ID of the flash area containing the region |
| * to erase. |
| * @param off The offset within the flash area to start the |
| * erase. |
| * @param sz The number of bytes to erase. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| static int |
| boot_erase_sector(int flash_area_id, uint32_t off, uint32_t sz) |
| { |
| const struct flash_area *fap; |
| int rc; |
| |
| rc = flash_area_open(flash_area_id, &fap); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = flash_area_erase(fap, off, sz); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = 0; |
| |
| done: |
| flash_area_close(fap); |
| return rc; |
| } |
| |
| /** |
| * Copies the contents of one flash region to another. You must erase the |
| * destination region prior to calling this function. |
| * |
| * @param flash_area_id_src The ID of the source flash area. |
| * @param flash_area_id_dst The ID of the destination flash area. |
| * @param off_src The offset within the source flash area to |
| * copy from. |
| * @param off_dst The offset within the destination flash area to |
| * copy to. |
| * @param sz The number of bytes to copy. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| static int |
| boot_copy_sector(int flash_area_id_src, int flash_area_id_dst, |
| uint32_t off_src, uint32_t off_dst, uint32_t sz) |
| { |
| const struct flash_area *fap_src; |
| const struct flash_area *fap_dst; |
| uint32_t bytes_copied; |
| int chunk_sz; |
| int rc; |
| |
| static uint8_t buf[1024]; |
| |
| fap_src = NULL; |
| fap_dst = NULL; |
| |
| rc = flash_area_open(flash_area_id_src, &fap_src); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = flash_area_open(flash_area_id_dst, &fap_dst); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| bytes_copied = 0; |
| while (bytes_copied < sz) { |
| if (sz - bytes_copied > sizeof buf) { |
| chunk_sz = sizeof buf; |
| } else { |
| chunk_sz = sz - bytes_copied; |
| } |
| |
| rc = flash_area_read(fap_src, off_src + bytes_copied, buf, chunk_sz); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| rc = flash_area_write(fap_dst, off_dst + bytes_copied, buf, chunk_sz); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto done; |
| } |
| |
| bytes_copied += chunk_sz; |
| } |
| |
| rc = 0; |
| |
| done: |
| if (fap_src) { |
| flash_area_close(fap_src); |
| } |
| if (fap_dst) { |
| flash_area_close(fap_dst); |
| } |
| return rc; |
| } |
| |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static inline int |
| boot_status_init_by_id(int flash_area_id, const struct boot_status *bs) |
| { |
| const struct flash_area *fap; |
| struct boot_swap_state swap_state; |
| int rc; |
| |
| rc = flash_area_open(flash_area_id, &fap); |
| assert(rc == 0); |
| |
| rc = boot_read_swap_state_by_id(FLASH_AREA_IMAGE_1, &swap_state); |
| assert(rc == 0); |
| |
| if (swap_state.image_ok == BOOT_FLAG_SET) { |
| rc = boot_write_image_ok(fap); |
| assert(rc == 0); |
| } |
| |
| rc = boot_write_swap_size(fap, bs->swap_size); |
| assert(rc == 0); |
| |
| rc = boot_write_magic(fap); |
| assert(rc == 0); |
| |
| flash_area_close(fap); |
| |
| return 0; |
| } |
| #endif |
| |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static int |
| boot_erase_last_sector_by_id(int flash_area_id) |
| { |
| uint8_t slot; |
| uint32_t last_sector; |
| int rc; |
| |
| switch (flash_area_id) { |
| case FLASH_AREA_IMAGE_0: |
| slot = 0; |
| break; |
| case FLASH_AREA_IMAGE_1: |
| slot = 1; |
| break; |
| default: |
| return BOOT_EFLASH; |
| } |
| |
| last_sector = boot_img_num_sectors(&boot_data, slot) - 1; |
| rc = boot_erase_sector(flash_area_id, |
| boot_img_sector_off(&boot_data, slot, last_sector), |
| boot_img_sector_size(&boot_data, slot, last_sector)); |
| assert(rc == 0); |
| |
| return rc; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| |
| /** |
| * Swaps the contents of two flash regions within the two image slots. |
| * |
| * @param idx The index of the first sector in the range of |
| * sectors being swapped. |
| * @param sz The number of bytes to swap. |
| * @param bs The current boot status. This struct gets |
| * updated according to the outcome. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static void |
| boot_swap_sectors(int idx, uint32_t sz, struct boot_status *bs) |
| { |
| const struct flash_area *fap; |
| uint32_t copy_sz; |
| uint32_t trailer_sz; |
| uint32_t img_off; |
| uint32_t scratch_trailer_off; |
| struct boot_swap_state swap_state; |
| size_t last_sector; |
| int rc; |
| |
| /* Calculate offset from start of image area. */ |
| img_off = boot_img_sector_off(&boot_data, 0, idx); |
| |
| copy_sz = sz; |
| trailer_sz = boot_slots_trailer_sz(BOOT_WRITE_SZ(&boot_data)); |
| |
| /* sz in this function is always is always sized on a multiple of the |
| * sector size. The check against the start offset of the last sector |
| * is to determine if we're swapping the last sector. The last sector |
| * needs special handling because it's where the trailer lives. If we're |
| * copying it, we need to use scratch to write the trailer temporarily. |
| * |
| * NOTE: `use_scratch` is a temporary flag (never written to flash) which |
| * controls if special handling is needed (swapping last sector). |
| */ |
| last_sector = boot_img_num_sectors(&boot_data, 0) - 1; |
| if (img_off + sz > boot_img_sector_off(&boot_data, 0, last_sector)) { |
| copy_sz -= trailer_sz; |
| } |
| |
| bs->use_scratch = (bs->idx == 0 && copy_sz != sz); |
| |
| if (bs->state == 0) { |
| rc = boot_erase_sector(FLASH_AREA_IMAGE_SCRATCH, 0, sz); |
| assert(rc == 0); |
| |
| rc = boot_copy_sector(FLASH_AREA_IMAGE_1, FLASH_AREA_IMAGE_SCRATCH, |
| img_off, 0, copy_sz); |
| assert(rc == 0); |
| |
| if (bs->idx == 0) { |
| if (bs->use_scratch) { |
| boot_status_init_by_id(FLASH_AREA_IMAGE_SCRATCH, bs); |
| } else { |
| /* Prepare the status area... here it is known that the |
| * last sector is not being used by the image data so it's |
| * safe to erase. |
| */ |
| rc = boot_erase_last_sector_by_id(FLASH_AREA_IMAGE_0); |
| assert(rc == 0); |
| |
| boot_status_init_by_id(FLASH_AREA_IMAGE_0, bs); |
| } |
| } |
| |
| bs->state = 1; |
| rc = boot_write_status(bs); |
| assert(rc == 0); |
| } |
| |
| if (bs->state == 1) { |
| rc = boot_erase_sector(FLASH_AREA_IMAGE_1, img_off, sz); |
| assert(rc == 0); |
| |
| rc = boot_copy_sector(FLASH_AREA_IMAGE_0, FLASH_AREA_IMAGE_1, |
| img_off, img_off, copy_sz); |
| assert(rc == 0); |
| |
| if (bs->idx == 0 && !bs->use_scratch) { |
| /* If not all sectors of the slot are being swapped, |
| * guarantee here that only slot0 will have the state. |
| */ |
| rc = boot_erase_last_sector_by_id(FLASH_AREA_IMAGE_1); |
| assert(rc == 0); |
| } |
| |
| bs->state = 2; |
| rc = boot_write_status(bs); |
| assert(rc == 0); |
| } |
| |
| if (bs->state == 2) { |
| rc = boot_erase_sector(FLASH_AREA_IMAGE_0, img_off, sz); |
| assert(rc == 0); |
| |
| /* NOTE: also copy trailer from scratch (has status info) */ |
| rc = boot_copy_sector(FLASH_AREA_IMAGE_SCRATCH, FLASH_AREA_IMAGE_0, |
| 0, img_off, copy_sz); |
| assert(rc == 0); |
| |
| if (bs->use_scratch) { |
| rc = flash_area_open(FLASH_AREA_IMAGE_SCRATCH, &fap); |
| assert(rc == 0); |
| |
| scratch_trailer_off = boot_status_off(fap); |
| |
| flash_area_close(fap); |
| |
| rc = flash_area_open(FLASH_AREA_IMAGE_0, &fap); |
| assert(rc == 0); |
| |
| /* copy current status that is being maintained in scratch */ |
| rc = boot_copy_sector(FLASH_AREA_IMAGE_SCRATCH, FLASH_AREA_IMAGE_0, |
| scratch_trailer_off, |
| img_off + copy_sz, |
| BOOT_STATUS_STATE_COUNT * BOOT_WRITE_SZ(&boot_data)); |
| assert(rc == 0); |
| |
| rc = boot_read_swap_state_by_id(FLASH_AREA_IMAGE_SCRATCH, |
| &swap_state); |
| assert(rc == 0); |
| |
| if (swap_state.image_ok == BOOT_FLAG_SET) { |
| rc = boot_write_image_ok(fap); |
| assert(rc == 0); |
| } |
| |
| rc = boot_write_swap_size(fap, bs->swap_size); |
| assert(rc == 0); |
| |
| rc = boot_write_magic(fap); |
| assert(rc == 0); |
| |
| flash_area_close(fap); |
| } |
| |
| bs->idx++; |
| bs->state = 0; |
| bs->use_scratch = 0; |
| rc = boot_write_status(bs); |
| assert(rc == 0); |
| } |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| |
| /** |
| * Swaps the two images in flash. If a prior copy operation was interrupted |
| * by a system reset, this function completes that operation. |
| * |
| * @param bs The current boot status. This function reads |
| * this struct to determine if it is resuming |
| * an interrupted swap operation. This |
| * function writes the updated status to this |
| * function on return. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| #ifdef MCUBOOT_OVERWRITE_ONLY |
| static int |
| boot_copy_image(struct boot_status *bs) |
| { |
| size_t sect_count; |
| size_t sect; |
| int rc; |
| size_t size = 0; |
| size_t this_size; |
| |
| BOOT_LOG_INF("Image upgrade slot1 -> slot0"); |
| BOOT_LOG_INF("Erasing slot0"); |
| |
| sect_count = boot_img_num_sectors(&boot_data, 0); |
| for (sect = 0; sect < sect_count; sect++) { |
| this_size = boot_img_sector_size(&boot_data, 0, sect); |
| rc = boot_erase_sector(FLASH_AREA_IMAGE_0, |
| size, |
| this_size); |
| assert(rc == 0); |
| |
| size += this_size; |
| } |
| |
| BOOT_LOG_INF("Copying slot 1 to slot 0: 0x%lx bytes", size); |
| rc = boot_copy_sector(FLASH_AREA_IMAGE_1, FLASH_AREA_IMAGE_0, |
| 0, 0, size); |
| |
| /* Erase slot 1 so that we don't do the upgrade on every boot. |
| * TODO: Perhaps verify slot 0's signature again? */ |
| rc = boot_erase_sector(FLASH_AREA_IMAGE_1, |
| 0, boot_img_sector_size(&boot_data, 1, 0)); |
| assert(rc == 0); |
| |
| return 0; |
| } |
| #else |
| static int |
| boot_copy_image(struct boot_status *bs) |
| { |
| uint32_t sz; |
| int first_sector_idx; |
| int last_sector_idx; |
| int swap_idx; |
| struct image_header *hdr; |
| uint32_t size; |
| uint32_t copy_size; |
| int rc; |
| |
| /* FIXME: just do this if asked by user? */ |
| |
| size = copy_size = 0; |
| |
| if (bs->idx == 0 && bs->state == 0) { |
| /* |
| * No swap ever happened, so need to find the largest image which |
| * will be used to determine the amount of sectors to swap. |
| */ |
| hdr = boot_img_hdr(&boot_data, 0); |
| if (hdr->ih_magic == IMAGE_MAGIC) { |
| rc = boot_read_image_size(0, hdr, ©_size); |
| assert(rc == 0); |
| } |
| |
| hdr = boot_img_hdr(&boot_data, 1); |
| if (hdr->ih_magic == IMAGE_MAGIC) { |
| rc = boot_read_image_size(1, hdr, &size); |
| assert(rc == 0); |
| } |
| |
| if (size > copy_size) { |
| copy_size = size; |
| } |
| |
| bs->swap_size = copy_size; |
| } else { |
| /* |
| * If a swap was under way, the swap_size should already be present |
| * in the trailer... |
| */ |
| rc = boot_read_swap_size(&bs->swap_size); |
| assert(rc == 0); |
| |
| copy_size = bs->swap_size; |
| } |
| |
| size = 0; |
| last_sector_idx = 0; |
| while (1) { |
| size += boot_img_sector_size(&boot_data, 0, last_sector_idx); |
| if (size >= copy_size) { |
| break; |
| } |
| last_sector_idx++; |
| } |
| |
| swap_idx = 0; |
| while (last_sector_idx >= 0) { |
| sz = boot_copy_sz(last_sector_idx, &first_sector_idx); |
| if (swap_idx >= bs->idx) { |
| boot_swap_sectors(first_sector_idx, sz, bs); |
| } |
| |
| last_sector_idx = first_sector_idx - 1; |
| swap_idx++; |
| } |
| |
| return 0; |
| } |
| #endif |
| |
| /** |
| * Marks the image in slot 0 as fully copied. |
| */ |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static int |
| boot_set_copy_done(void) |
| { |
| const struct flash_area *fap; |
| int rc; |
| |
| rc = flash_area_open(FLASH_AREA_IMAGE_0, &fap); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| rc = boot_write_copy_done(fap); |
| flash_area_close(fap); |
| return rc; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| |
| /** |
| * Marks a reverted image in slot 0 as confirmed. This is necessary to ensure |
| * the status bytes from the image revert operation don't get processed on a |
| * subsequent boot. |
| * |
| * NOTE: image_ok is tested before writing because if there's a valid permanent |
| * image installed on slot0 and the new image to be upgrade to has a bad sig, |
| * image_ok would be overwritten. |
| */ |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| static int |
| boot_set_image_ok(void) |
| { |
| const struct flash_area *fap; |
| struct boot_swap_state state; |
| int rc; |
| |
| rc = flash_area_open(FLASH_AREA_IMAGE_0, &fap); |
| if (rc != 0) { |
| return BOOT_EFLASH; |
| } |
| |
| rc = boot_read_swap_state(fap, &state); |
| if (rc != 0) { |
| rc = BOOT_EFLASH; |
| goto out; |
| } |
| |
| if (state.image_ok == BOOT_FLAG_UNSET) { |
| rc = boot_write_image_ok(fap); |
| } |
| |
| out: |
| flash_area_close(fap); |
| return rc; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| |
| /** |
| * Performs an image swap if one is required. |
| * |
| * @param out_swap_type On success, the type of swap performed gets |
| * written here. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| static int |
| boot_swap_if_needed(int *out_swap_type) |
| { |
| struct boot_status bs; |
| int swap_type; |
| int rc; |
| |
| /* Determine if we rebooted in the middle of an image swap |
| * operation. |
| */ |
| rc = boot_read_status(&bs); |
| assert(rc == 0); |
| if (rc != 0) { |
| return rc; |
| } |
| |
| /* If a partial swap was detected, complete it. */ |
| if (bs.idx != 0 || bs.state != 0) { |
| rc = boot_copy_image(&bs); |
| assert(rc == 0); |
| |
| /* NOTE: here we have finished a swap resume. The initial request |
| * was either a TEST or PERM swap, which now after the completed |
| * swap will be determined to be respectively REVERT (was TEST) |
| * or NONE (was PERM). |
| */ |
| |
| /* Extrapolate the type of the partial swap. We need this |
| * information to know how to mark the swap complete in flash. |
| */ |
| swap_type = boot_previous_swap_type(); |
| } else { |
| swap_type = boot_validated_swap_type(); |
| switch (swap_type) { |
| case BOOT_SWAP_TYPE_TEST: |
| case BOOT_SWAP_TYPE_PERM: |
| case BOOT_SWAP_TYPE_REVERT: |
| rc = boot_copy_image(&bs); |
| assert(rc == 0); |
| break; |
| } |
| } |
| |
| *out_swap_type = swap_type; |
| return 0; |
| } |
| |
| /** |
| * Prepares the booting process. This function moves images around in flash as |
| * appropriate, and tells you what address to boot from. |
| * |
| * @param rsp On success, indicates how booting should occur. |
| * |
| * @return 0 on success; nonzero on failure. |
| */ |
| int |
| boot_go(struct boot_rsp *rsp) |
| { |
| int swap_type; |
| size_t slot; |
| int rc; |
| int fa_id; |
| bool reload_headers = false; |
| |
| /* The array of slot sectors are defined here (as opposed to file scope) so |
| * that they don't get allocated for non-boot-loader apps. This is |
| * necessary because the gcc option "-fdata-sections" doesn't seem to have |
| * any effect in older gcc versions (e.g., 4.8.4). |
| */ |
| static boot_sector_t slot0_sectors[BOOT_MAX_IMG_SECTORS]; |
| static boot_sector_t slot1_sectors[BOOT_MAX_IMG_SECTORS]; |
| boot_data.imgs[0].sectors = slot0_sectors; |
| boot_data.imgs[1].sectors = slot1_sectors; |
| |
| /* Open boot_data image areas for the duration of this call. */ |
| for (slot = 0; slot < BOOT_NUM_SLOTS; slot++) { |
| fa_id = flash_area_id_from_image_slot(slot); |
| rc = flash_area_open(fa_id, &BOOT_IMG_AREA(&boot_data, slot)); |
| assert(rc == 0); |
| } |
| rc = flash_area_open(FLASH_AREA_IMAGE_SCRATCH, |
| &BOOT_SCRATCH_AREA(&boot_data)); |
| assert(rc == 0); |
| |
| /* Determine the sector layout of the image slots and scratch area. */ |
| rc = boot_read_sectors(); |
| if (rc != 0) { |
| goto out; |
| } |
| |
| /* Attempt to read an image header from each slot. */ |
| rc = boot_read_image_headers(); |
| if (rc != 0) { |
| goto out; |
| } |
| |
| /* If the image slots aren't compatible, no swap is possible. Just boot |
| * into slot 0. |
| */ |
| if (boot_slots_compatible()) { |
| rc = boot_swap_if_needed(&swap_type); |
| assert(rc == 0); |
| if (rc != 0) { |
| goto out; |
| } |
| |
| /* |
| * The following states need image_ok be explicitly set after the |
| * swap was finished to avoid a new revert. |
| */ |
| if (swap_type == BOOT_SWAP_TYPE_REVERT || swap_type == BOOT_SWAP_TYPE_FAIL) { |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| rc = boot_set_image_ok(); |
| if (rc != 0) { |
| swap_type = BOOT_SWAP_TYPE_PANIC; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| } |
| } else { |
| swap_type = BOOT_SWAP_TYPE_NONE; |
| } |
| |
| switch (swap_type) { |
| case BOOT_SWAP_TYPE_NONE: |
| slot = 0; |
| break; |
| |
| case BOOT_SWAP_TYPE_TEST: /* fallthrough */ |
| case BOOT_SWAP_TYPE_PERM: /* fallthrough */ |
| case BOOT_SWAP_TYPE_REVERT: |
| slot = 1; |
| reload_headers = true; |
| #ifndef MCUBOOT_OVERWRITE_ONLY |
| rc = boot_set_copy_done(); |
| if (rc != 0) { |
| swap_type = BOOT_SWAP_TYPE_PANIC; |
| } |
| #endif /* !MCUBOOT_OVERWRITE_ONLY */ |
| break; |
| |
| case BOOT_SWAP_TYPE_FAIL: |
| /* The image in slot 1 was invalid and is now erased. Ensure we don't |
| * try to boot into it again on the next reboot. Do this by pretending |
| * we just reverted back to slot 0. |
| */ |
| slot = 0; |
| reload_headers = true; |
| break; |
| |
| default: |
| swap_type = BOOT_SWAP_TYPE_PANIC; |
| } |
| |
| if (swap_type == BOOT_SWAP_TYPE_PANIC) { |
| BOOT_LOG_ERR("panic!"); |
| assert(0); |
| |
| /* Loop forever... */ |
| while (1) {} |
| } |
| |
| #ifdef MCUBOOT_VALIDATE_SLOT0 |
| if (reload_headers) { |
| rc = boot_read_image_headers(); |
| if (rc != 0) { |
| goto out; |
| } |
| /* Since headers were reloaded, it can be assumed we just performed a |
| * swap or overwrite. Now the header info that should be used to |
| * provide the data for the bootstrap, which previously was at Slot 1, |
| * was updated to Slot 0. |
| */ |
| slot = 0; |
| } |
| |
| rc = boot_validate_slot(0); |
| assert(rc == 0); |
| if (rc != 0) { |
| rc = BOOT_EBADIMAGE; |
| goto out; |
| } |
| #else |
| (void)reload_headers; |
| #endif |
| |
| /* Always boot from the primary slot. */ |
| rsp->br_flash_dev_id = boot_img_fa_device_id(&boot_data, 0); |
| rsp->br_image_off = boot_img_slot_off(&boot_data, 0); |
| rsp->br_hdr = boot_img_hdr(&boot_data, slot); |
| |
| out: |
| flash_area_close(BOOT_SCRATCH_AREA(&boot_data)); |
| for (slot = 0; slot < BOOT_NUM_SLOTS; slot++) { |
| flash_area_close(BOOT_IMG_AREA(&boot_data, BOOT_NUM_SLOTS - 1 - slot)); |
| } |
| return rc; |
| } |
| |
| int |
| split_go(int loader_slot, int split_slot, void **entry) |
| { |
| boot_sector_t *sectors; |
| uintptr_t entry_val; |
| int loader_flash_id; |
| int split_flash_id; |
| int rc; |
| |
| sectors = malloc(BOOT_MAX_IMG_SECTORS * 2 * sizeof *sectors); |
| if (sectors == NULL) { |
| return SPLIT_GO_ERR; |
| } |
| boot_data.imgs[loader_slot].sectors = sectors + 0; |
| boot_data.imgs[split_slot].sectors = sectors + BOOT_MAX_IMG_SECTORS; |
| |
| loader_flash_id = flash_area_id_from_image_slot(loader_slot); |
| rc = flash_area_open(loader_flash_id, |
| &BOOT_IMG_AREA(&boot_data, split_slot)); |
| assert(rc == 0); |
| split_flash_id = flash_area_id_from_image_slot(split_slot); |
| rc = flash_area_open(split_flash_id, |
| &BOOT_IMG_AREA(&boot_data, split_slot)); |
| assert(rc == 0); |
| |
| /* Determine the sector layout of the image slots and scratch area. */ |
| rc = boot_read_sectors(); |
| if (rc != 0) { |
| rc = SPLIT_GO_ERR; |
| goto done; |
| } |
| |
| rc = boot_read_image_headers(); |
| if (rc != 0) { |
| goto done; |
| } |
| |
| /* Don't check the bootable image flag because we could really call a |
| * bootable or non-bootable image. Just validate that the image check |
| * passes which is distinct from the normal check. |
| */ |
| rc = split_image_check(boot_img_hdr(&boot_data, split_slot), |
| BOOT_IMG_AREA(&boot_data, split_slot), |
| boot_img_hdr(&boot_data, loader_slot), |
| BOOT_IMG_AREA(&boot_data, loader_slot)); |
| if (rc != 0) { |
| rc = SPLIT_GO_NON_MATCHING; |
| goto done; |
| } |
| |
| entry_val = boot_img_slot_off(&boot_data, split_slot) + |
| boot_img_hdr(&boot_data, split_slot)->ih_hdr_size; |
| *entry = (void *) entry_val; |
| rc = SPLIT_GO_OK; |
| |
| done: |
| flash_area_close(BOOT_IMG_AREA(&boot_data, split_slot)); |
| flash_area_close(BOOT_IMG_AREA(&boot_data, loader_slot)); |
| free(sectors); |
| return rc; |
| } |