blob: 42e157beadbf938c4f0c26d2d56d777a5b24cfbc [file] [log] [blame]
/*
* Copyright (c) 2016-2024, Arm Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <inttypes.h>
#include <stdio.h>
#include <string.h>
#include <common/debug.h>
#include <common/tf_crc32.h>
#include <drivers/io/io_storage.h>
#include <drivers/partition/efi.h>
#include <drivers/partition/partition.h>
#include <drivers/partition/gpt.h>
#include <drivers/partition/mbr.h>
#include <plat/common/platform.h>
static uint8_t mbr_sector[PLAT_PARTITION_BLOCK_SIZE];
static partition_entry_list_t list;
#if LOG_LEVEL >= LOG_LEVEL_VERBOSE
static void dump_entries(int num)
{
char name[EFI_NAMELEN];
int i, j, len;
VERBOSE("Partition table with %d entries:\n", num);
for (i = 0; i < num; i++) {
len = snprintf(name, EFI_NAMELEN, "%s", list.list[i].name);
for (j = 0; j < EFI_NAMELEN - len - 1; j++) {
name[len + j] = ' ';
}
name[EFI_NAMELEN - 1] = '\0';
VERBOSE("%d: %s %" PRIx64 "-%" PRIx64 "\n", i + 1, name, list.list[i].start,
list.list[i].start + list.list[i].length - 4);
}
}
#else
#define dump_entries(num) ((void)num)
#endif
/*
* Load the first sector that carries MBR header.
* The MBR boot signature should be always valid whether it's MBR or GPT.
*/
static int load_mbr_header(uintptr_t image_handle, mbr_entry_t *mbr_entry)
{
size_t bytes_read;
int result;
mbr_entry_t *tmp;
assert(mbr_entry != NULL);
/* MBR partition table is in LBA0. */
result = io_seek(image_handle, IO_SEEK_SET, MBR_OFFSET);
if (result != 0) {
VERBOSE("Failed to seek (%i)\n", result);
return result;
}
result = io_read(image_handle, (uintptr_t)&mbr_sector,
PLAT_PARTITION_BLOCK_SIZE, &bytes_read);
if ((result != 0) || (bytes_read != PLAT_PARTITION_BLOCK_SIZE)) {
VERBOSE("Failed to read data (%i)\n", result);
return result;
}
/* Check MBR boot signature. */
if ((mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 2] != MBR_SIGNATURE_FIRST) ||
(mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 1] != MBR_SIGNATURE_SECOND)) {
VERBOSE("MBR boot signature failure\n");
return -ENOENT;
}
tmp = (mbr_entry_t *)(&mbr_sector[MBR_PRIMARY_ENTRY_OFFSET]);
if (tmp->first_lba != 1) {
VERBOSE("MBR header may have an invalid first LBA\n");
return -EINVAL;
}
if ((tmp->sector_nums == 0) || (tmp->sector_nums == UINT32_MAX)) {
VERBOSE("MBR header entry has an invalid number of sectors\n");
return -EINVAL;
}
memcpy(mbr_entry, tmp, sizeof(mbr_entry_t));
return 0;
}
/*
* Load GPT header and check the GPT signature and header CRC.
* If partition numbers could be found, check & update it.
*/
static int load_gpt_header(uintptr_t image_handle, size_t header_offset,
gpt_header_t *header)
{
size_t bytes_read;
int result;
uint32_t header_crc, calc_crc;
result = io_seek(image_handle, IO_SEEK_SET, header_offset);
if (result != 0) {
VERBOSE("Failed to seek into the GPT image at offset (%zu)\n",
header_offset);
return result;
}
result = io_read(image_handle, (uintptr_t)header,
sizeof(gpt_header_t), &bytes_read);
if ((result != 0) || (sizeof(gpt_header_t) != bytes_read)) {
VERBOSE("GPT header read error(%i) or read mismatch occurred,"
"expected(%zu) and actual(%zu)\n", result,
sizeof(gpt_header_t), bytes_read);
return result;
}
if (memcmp(header->signature, GPT_SIGNATURE,
sizeof(header->signature)) != 0) {
VERBOSE("GPT header signature failure\n");
return -EINVAL;
}
/*
* UEFI Spec 2.8 March 2019 Page 119: HeaderCRC32 value is
* computed by setting this field to 0, and computing the
* 32-bit CRC for HeaderSize bytes.
*/
header_crc = header->header_crc;
header->header_crc = 0U;
calc_crc = tf_crc32(0U, (uint8_t *)header, sizeof(gpt_header_t));
if (header_crc != calc_crc) {
ERROR("Invalid GPT Header CRC: Expected 0x%x but got 0x%x.\n",
header_crc, calc_crc);
return -EINVAL;
}
header->header_crc = header_crc;
/* partition numbers can't exceed PLAT_PARTITION_MAX_ENTRIES */
list.entry_count = header->list_num;
if (list.entry_count > PLAT_PARTITION_MAX_ENTRIES) {
list.entry_count = PLAT_PARTITION_MAX_ENTRIES;
}
return 0;
}
/*
* Load a single MBR entry based on details from MBR header.
*/
static int load_mbr_entry(uintptr_t image_handle, mbr_entry_t *mbr_entry,
int part_number)
{
size_t bytes_read;
uintptr_t offset;
int result;
assert(mbr_entry != NULL);
/* MBR partition table is in LBA0. */
result = io_seek(image_handle, IO_SEEK_SET, MBR_OFFSET);
if (result != 0) {
VERBOSE("Failed to seek (%i)\n", result);
return result;
}
result = io_read(image_handle, (uintptr_t)&mbr_sector,
PLAT_PARTITION_BLOCK_SIZE, &bytes_read);
if (result != 0) {
VERBOSE("Failed to read data (%i)\n", result);
return result;
}
/* Check MBR boot signature. */
if ((mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 2] != MBR_SIGNATURE_FIRST) ||
(mbr_sector[LEGACY_PARTITION_BLOCK_SIZE - 1] != MBR_SIGNATURE_SECOND)) {
VERBOSE("MBR Entry boot signature failure\n");
return -ENOENT;
}
offset = (uintptr_t)&mbr_sector +
MBR_PRIMARY_ENTRY_OFFSET +
MBR_PRIMARY_ENTRY_SIZE * part_number;
memcpy(mbr_entry, (void *)offset, sizeof(mbr_entry_t));
return 0;
}
/*
* Load MBR entries based on max number of partition entries.
*/
static int load_mbr_entries(uintptr_t image_handle)
{
mbr_entry_t mbr_entry;
int i;
list.entry_count = MBR_PRIMARY_ENTRY_NUMBER;
for (i = 0; i < list.entry_count; i++) {
load_mbr_entry(image_handle, &mbr_entry, i);
list.list[i].start = mbr_entry.first_lba * 512;
list.list[i].length = mbr_entry.sector_nums * 512;
list.list[i].name[0] = mbr_entry.type;
}
return 0;
}
/*
* Try to read and load a single GPT entry.
*/
static int load_gpt_entry(uintptr_t image_handle, gpt_entry_t *entry)
{
size_t bytes_read = 0U;
int result;
assert(entry != NULL);
result = io_read(image_handle, (uintptr_t)entry, sizeof(gpt_entry_t),
&bytes_read);
if ((result != 0) || (sizeof(gpt_entry_t) != bytes_read)) {
VERBOSE("GPT Entry read error(%i) or read mismatch occurred,"
"expected(%zu) and actual(%zu)\n", result,
sizeof(gpt_entry_t), bytes_read);
return -EINVAL;
}
return result;
}
/*
* Retrieve each entry in the partition table, parse the data from each
* entry and store them in the list of partition table entries.
*/
static int load_partition_gpt(uintptr_t image_handle, gpt_header_t header)
{
const signed long long gpt_entry_offset = LBA(header.part_lba);
gpt_entry_t entry;
int result;
unsigned int i;
uint32_t calc_crc = 0U;
result = io_seek(image_handle, IO_SEEK_SET, gpt_entry_offset);
if (result != 0) {
VERBOSE("Failed to seek (%i), Failed loading GPT partition"
"table entries\n", result);
return result;
}
for (i = 0; i < (unsigned int)list.entry_count; i++) {
result = load_gpt_entry(image_handle, &entry);
if (result != 0) {
VERBOSE("Failed to load gpt entry data(%u) error is (%i)\n",
i, result);
return result;
}
result = parse_gpt_entry(&entry, &list.list[i]);
if (result != 0) {
result = io_seek(image_handle, IO_SEEK_SET,
(gpt_entry_offset + (i * sizeof(gpt_entry_t))));
if (result != 0) {
VERBOSE("Failed to seek (%i)\n", result);
return result;
}
break;
}
/*
* Calculate CRC of Partition entry array to compare with CRC
* value in header
*/
calc_crc = tf_crc32(calc_crc, (uint8_t *)&entry, sizeof(gpt_entry_t));
}
if (i == 0) {
VERBOSE("No Valid GPT Entries found\n");
return -EINVAL;
}
/*
* Only records the valid partition number that is loaded from
* partition table.
*/
list.entry_count = i;
dump_entries(list.entry_count);
/*
* If there are less valid entries than the possible number of entries
* from the header, continue to load the partition entry table to
* calculate the full CRC in order to check against the partition CRC
* from the header for validation.
*/
for (; i < header.list_num; i++) {
result = load_gpt_entry(image_handle, &entry);
if (result != 0) {
VERBOSE("Failed to load gpt entry data(%u) error is (%i)\n",
i, result);
return result;
}
calc_crc = tf_crc32(calc_crc, (uint8_t *)&entry, sizeof(gpt_entry_t));
}
if (header.part_crc != calc_crc) {
ERROR("Invalid GPT Partition Array Entry CRC: Expected 0x%x"
" but got 0x%x.\n", header.part_crc, calc_crc);
return -EINVAL;
}
return 0;
}
/*
* Try retrieving and parsing the backup-GPT header and backup GPT entries.
* Last 33 blocks contains the backup-GPT entries and header.
*/
static int load_backup_gpt(unsigned int image_id, unsigned int sector_nums)
{
int result;
gpt_header_t header;
size_t gpt_header_offset;
uintptr_t dev_handle, image_spec, image_handle;
io_block_spec_t *block_spec;
int part_num_entries;
result = plat_get_image_source(image_id, &dev_handle, &image_spec);
if (result != 0) {
VERBOSE("Failed to obtain reference to image id=%u (%i)\n",
image_id, result);
return result;
}
block_spec = (io_block_spec_t *)image_spec;
/*
* We need to read 32 blocks of GPT entries and one block of GPT header
* try mapping only last 33 last blocks from the image to read the
* Backup-GPT header and its entries.
*/
part_num_entries = (PLAT_PARTITION_MAX_ENTRIES / 4);
/* Move the offset base to LBA-33 */
block_spec->offset += LBA(sector_nums - part_num_entries);
/*
* Set length as LBA-33, 32 blocks of backup-GPT entries and one
* block of backup-GPT header.
*/
block_spec->length = LBA(part_num_entries + 1);
result = io_open(dev_handle, image_spec, &image_handle);
if (result != 0) {
VERBOSE("Failed to access image id (%i)\n", result);
return result;
}
INFO("Trying to retrieve back-up GPT header\n");
/* Last block is backup-GPT header, after the end of GPT entries */
gpt_header_offset = LBA(part_num_entries);
result = load_gpt_header(image_handle, gpt_header_offset, &header);
if ((result != 0) || (header.part_lba == 0)) {
ERROR("Failed to retrieve Backup GPT header,"
"Partition maybe corrupted\n");
goto out;
}
/*
* Note we mapped last 33 blocks(LBA-33), first block here starts with
* entries while last block was header.
*/
header.part_lba = 0;
result = load_partition_gpt(image_handle, header);
out:
io_close(image_handle);
return result;
}
/*
* Load a GPT partition, Try retrieving and parsing the primary GPT header,
* if its corrupted try loading backup GPT header and then retrieve list
* of partition table entries found from the GPT.
*/
static int load_primary_gpt(uintptr_t image_handle, unsigned int first_lba)
{
int result;
size_t gpt_header_offset;
gpt_header_t header;
/* Try to load Primary GPT header from LBA1 */
gpt_header_offset = LBA(first_lba);
result = load_gpt_header(image_handle, gpt_header_offset, &header);
if ((result != 0) || (header.part_lba == 0)) {
VERBOSE("Failed to retrieve Primary GPT header,"
"trying to retrieve back-up GPT header\n");
return result;
}
return load_partition_gpt(image_handle, header);
}
/*
* Load the partition table info based on the image id provided.
*/
int load_partition_table(unsigned int image_id)
{
uintptr_t dev_handle, image_handle, image_spec = 0;
mbr_entry_t mbr_entry;
int result;
result = plat_get_image_source(image_id, &dev_handle, &image_spec);
if (result != 0) {
VERBOSE("Failed to obtain reference to image id=%u (%i)\n",
image_id, result);
return result;
}
result = io_open(dev_handle, image_spec, &image_handle);
if (result != 0) {
VERBOSE("Failed to access image id=%u (%i)\n", image_id, result);
return result;
}
result = load_mbr_header(image_handle, &mbr_entry);
if (result != 0) {
VERBOSE("Failed to access image id=%u (%i)\n", image_id, result);
goto out;
}
if (mbr_entry.type == PARTITION_TYPE_GPT) {
result = load_primary_gpt(image_handle, mbr_entry.first_lba);
if (result != 0) {
io_close(image_handle);
return load_backup_gpt(BKUP_GPT_IMAGE_ID,
mbr_entry.sector_nums);
}
} else {
result = load_mbr_entries(image_handle);
}
out:
io_close(image_handle);
return result;
}
/*
* Try retrieving a partition table entry based on the name of the partition.
*/
const partition_entry_t *get_partition_entry(const char *name)
{
int i;
for (i = 0; i < list.entry_count; i++) {
if (strcmp(name, list.list[i].name) == 0) {
return &list.list[i];
}
}
return NULL;
}
/*
* Try retrieving a partition table entry based on the partition type GUID.
*/
const partition_entry_t *get_partition_entry_by_type(
const struct efi_guid *type_guid)
{
int i;
for (i = 0; i < list.entry_count; i++) {
if (guidcmp(type_guid, &list.list[i].type_guid) == 0) {
return &list.list[i];
}
}
return NULL;
}
/*
* Try retrieving a partition table entry based on the unique partition GUID.
*/
const partition_entry_t *get_partition_entry_by_guid(
const struct efi_guid *part_guid)
{
int i;
for (i = 0; i < list.entry_count; i++) {
if (guidcmp(part_guid, &list.list[i].part_guid) == 0) {
return &list.list[i];
}
}
return NULL;
}
/*
* Return entry to the list of partition table entries.
*/
const partition_entry_list_t *get_partition_entry_list(void)
{
return &list;
}
/*
* Try loading partition table info for the given image ID.
*/
void partition_init(unsigned int image_id)
{
int ret;
ret = load_partition_table(image_id);
if (ret != 0) {
ERROR("Failed to parse partition with image id = %u\n",
image_id);
}
}
/*
* Load a GPT based image.
*/
int gpt_partition_init(void)
{
return load_partition_table(GPT_IMAGE_ID);
}