u-boot/disk/part_efi.c
Maxime Ripard b349abbfe9 gpt: Fix the protective MBR partition size
According to the UEFI Spec (Table 16, section 5.2.3 of the version 2.4 Errata
B), the protective MBR partition record size must be set to the size of the
disk minus one, in LBAs.

However, the current code was setting the size as the total number of LBAs on
the disk, resulting in an off-by-one error.

This confused the AM335x ROM code, and will probably confuse other tools as
well.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
2015-01-08 11:00:45 -05:00

814 lines
21 KiB
C

/*
* Copyright (C) 2008 RuggedCom, Inc.
* Richard Retanubun <RichardRetanubun@RuggedCom.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* NOTE:
* when CONFIG_SYS_64BIT_LBA is not defined, lbaint_t is 32 bits; this
* limits the maximum size of addressable storage to < 2 Terra Bytes
*/
#include <asm/unaligned.h>
#include <common.h>
#include <command.h>
#include <ide.h>
#include <inttypes.h>
#include <malloc.h>
#include <part_efi.h>
#include <linux/ctype.h>
DECLARE_GLOBAL_DATA_PTR;
#ifdef HAVE_BLOCK_DEVICE
/**
* efi_crc32() - EFI version of crc32 function
* @buf: buffer to calculate crc32 of
* @len - length of buf
*
* Description: Returns EFI-style CRC32 value for @buf
*/
static inline u32 efi_crc32(const void *buf, u32 len)
{
return crc32(0, buf, len);
}
/*
* Private function prototypes
*/
static int pmbr_part_valid(struct partition *part);
static int is_pmbr_valid(legacy_mbr * mbr);
static int is_gpt_valid(block_dev_desc_t *dev_desc, u64 lba,
gpt_header *pgpt_head, gpt_entry **pgpt_pte);
static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
gpt_header * pgpt_head);
static int is_pte_valid(gpt_entry * pte);
static char *print_efiname(gpt_entry *pte)
{
static char name[PARTNAME_SZ + 1];
int i;
for (i = 0; i < PARTNAME_SZ; i++) {
u8 c;
c = pte->partition_name[i] & 0xff;
c = (c && !isprint(c)) ? '.' : c;
name[i] = c;
}
name[PARTNAME_SZ] = 0;
return name;
}
static efi_guid_t system_guid = PARTITION_SYSTEM_GUID;
static inline int is_bootable(gpt_entry *p)
{
return p->attributes.fields.legacy_bios_bootable ||
!memcmp(&(p->partition_type_guid), &system_guid,
sizeof(efi_guid_t));
}
static int validate_gpt_header(gpt_header *gpt_h, lbaint_t lba,
lbaint_t lastlba)
{
uint32_t crc32_backup = 0;
uint32_t calc_crc32;
/* Check the GPT header signature */
if (le64_to_cpu(gpt_h->signature) != GPT_HEADER_SIGNATURE) {
printf("%s signature is wrong: 0x%llX != 0x%llX\n",
"GUID Partition Table Header",
le64_to_cpu(gpt_h->signature),
GPT_HEADER_SIGNATURE);
return -1;
}
/* Check the GUID Partition Table CRC */
memcpy(&crc32_backup, &gpt_h->header_crc32, sizeof(crc32_backup));
memset(&gpt_h->header_crc32, 0, sizeof(gpt_h->header_crc32));
calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
le32_to_cpu(gpt_h->header_size));
memcpy(&gpt_h->header_crc32, &crc32_backup, sizeof(crc32_backup));
if (calc_crc32 != le32_to_cpu(crc32_backup)) {
printf("%s CRC is wrong: 0x%x != 0x%x\n",
"GUID Partition Table Header",
le32_to_cpu(crc32_backup), calc_crc32);
return -1;
}
/*
* Check that the my_lba entry points to the LBA that contains the GPT
*/
if (le64_to_cpu(gpt_h->my_lba) != lba) {
printf("GPT: my_lba incorrect: %llX != " LBAF "\n",
le64_to_cpu(gpt_h->my_lba),
lba);
return -1;
}
/*
* Check that the first_usable_lba and that the last_usable_lba are
* within the disk.
*/
if (le64_to_cpu(gpt_h->first_usable_lba) > lastlba) {
printf("GPT: first_usable_lba incorrect: %llX > " LBAF "\n",
le64_to_cpu(gpt_h->first_usable_lba), lastlba);
return -1;
}
if (le64_to_cpu(gpt_h->last_usable_lba) > lastlba) {
printf("GPT: last_usable_lba incorrect: %llX > " LBAF "\n",
le64_to_cpu(gpt_h->last_usable_lba), lastlba);
return -1;
}
debug("GPT: first_usable_lba: %llX last_usable_lba: %llX last lba: "
LBAF "\n", le64_to_cpu(gpt_h->first_usable_lba),
le64_to_cpu(gpt_h->last_usable_lba), lastlba);
return 0;
}
static int validate_gpt_entries(gpt_header *gpt_h, gpt_entry *gpt_e)
{
uint32_t calc_crc32;
/* Check the GUID Partition Table Entry Array CRC */
calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
le32_to_cpu(gpt_h->num_partition_entries) *
le32_to_cpu(gpt_h->sizeof_partition_entry));
if (calc_crc32 != le32_to_cpu(gpt_h->partition_entry_array_crc32)) {
printf("%s: 0x%x != 0x%x\n",
"GUID Partition Table Entry Array CRC is wrong",
le32_to_cpu(gpt_h->partition_entry_array_crc32),
calc_crc32);
return -1;
}
return 0;
}
static void prepare_backup_gpt_header(gpt_header *gpt_h)
{
uint32_t calc_crc32;
uint64_t val;
/* recalculate the values for the Backup GPT Header */
val = le64_to_cpu(gpt_h->my_lba);
gpt_h->my_lba = gpt_h->alternate_lba;
gpt_h->alternate_lba = cpu_to_le64(val);
gpt_h->partition_entry_lba =
cpu_to_le64(le64_to_cpu(gpt_h->last_usable_lba) + 1);
gpt_h->header_crc32 = 0;
calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
le32_to_cpu(gpt_h->header_size));
gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
}
#ifdef CONFIG_EFI_PARTITION
/*
* Public Functions (include/part.h)
*/
void print_part_efi(block_dev_desc_t * dev_desc)
{
ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
gpt_entry *gpt_pte = NULL;
int i = 0;
char uuid[37];
unsigned char *uuid_bin;
if (!dev_desc) {
printf("%s: Invalid Argument(s)\n", __func__);
return;
}
/* This function validates AND fills in the GPT header and PTE */
if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
gpt_head, &gpt_pte) != 1) {
printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
gpt_head, &gpt_pte) != 1) {
printf("%s: *** ERROR: Invalid Backup GPT ***\n",
__func__);
return;
} else {
printf("%s: *** Using Backup GPT ***\n",
__func__);
}
}
debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
printf("Part\tStart LBA\tEnd LBA\t\tName\n");
printf("\tAttributes\n");
printf("\tType GUID\n");
printf("\tPartition GUID\n");
for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
/* Stop at the first non valid PTE */
if (!is_pte_valid(&gpt_pte[i]))
break;
printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
le64_to_cpu(gpt_pte[i].starting_lba),
le64_to_cpu(gpt_pte[i].ending_lba),
print_efiname(&gpt_pte[i]));
printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b;
uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
printf("\ttype:\t%s\n", uuid);
uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b;
uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
printf("\tguid:\t%s\n", uuid);
}
/* Remember to free pte */
free(gpt_pte);
return;
}
int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
disk_partition_t * info)
{
ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
gpt_entry *gpt_pte = NULL;
/* "part" argument must be at least 1 */
if (!dev_desc || !info || part < 1) {
printf("%s: Invalid Argument(s)\n", __func__);
return -1;
}
/* This function validates AND fills in the GPT header and PTE */
if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
gpt_head, &gpt_pte) != 1) {
printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
gpt_head, &gpt_pte) != 1) {
printf("%s: *** ERROR: Invalid Backup GPT ***\n",
__func__);
return -1;
} else {
printf("%s: *** Using Backup GPT ***\n",
__func__);
}
}
if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
!is_pte_valid(&gpt_pte[part - 1])) {
debug("%s: *** ERROR: Invalid partition number %d ***\n",
__func__, part);
free(gpt_pte);
return -1;
}
/* The 'lbaint_t' casting may limit the maximum disk size to 2 TB */
info->start = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].starting_lba);
/* The ending LBA is inclusive, to calculate size, add 1 to it */
info->size = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1
- info->start;
info->blksz = dev_desc->blksz;
sprintf((char *)info->name, "%s",
print_efiname(&gpt_pte[part - 1]));
sprintf((char *)info->type, "U-Boot");
info->bootable = is_bootable(&gpt_pte[part - 1]);
#ifdef CONFIG_PARTITION_UUIDS
uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
UUID_STR_FORMAT_GUID);
#endif
debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s\n", __func__,
info->start, info->size, info->name);
/* Remember to free pte */
free(gpt_pte);
return 0;
}
int get_partition_info_efi_by_name(block_dev_desc_t *dev_desc,
const char *name, disk_partition_t *info)
{
int ret;
int i;
for (i = 1; i < GPT_ENTRY_NUMBERS; i++) {
ret = get_partition_info_efi(dev_desc, i, info);
if (ret != 0) {
/* no more entries in table */
return -1;
}
if (strcmp(name, (const char *)info->name) == 0) {
/* matched */
return 0;
}
}
return -2;
}
int test_part_efi(block_dev_desc_t * dev_desc)
{
ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
/* Read legacy MBR from block 0 and validate it */
if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)legacymbr) != 1)
|| (is_pmbr_valid(legacymbr) != 1)) {
return -1;
}
return 0;
}
/**
* set_protective_mbr(): Set the EFI protective MBR
* @param dev_desc - block device descriptor
*
* @return - zero on success, otherwise error
*/
static int set_protective_mbr(block_dev_desc_t *dev_desc)
{
/* Setup the Protective MBR */
ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
memset(p_mbr, 0, sizeof(*p_mbr));
if (p_mbr == NULL) {
printf("%s: calloc failed!\n", __func__);
return -1;
}
/* Append signature */
p_mbr->signature = MSDOS_MBR_SIGNATURE;
p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
p_mbr->partition_record[0].start_sect = 1;
p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba - 1;
/* Write MBR sector to the MMC device */
if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) {
printf("** Can't write to device %d **\n",
dev_desc->dev);
return -1;
}
return 0;
}
int write_gpt_table(block_dev_desc_t *dev_desc,
gpt_header *gpt_h, gpt_entry *gpt_e)
{
const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
* sizeof(gpt_entry)), dev_desc);
u32 calc_crc32;
debug("max lba: %x\n", (u32) dev_desc->lba);
/* Setup the Protective MBR */
if (set_protective_mbr(dev_desc) < 0)
goto err;
/* Generate CRC for the Primary GPT Header */
calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
le32_to_cpu(gpt_h->num_partition_entries) *
le32_to_cpu(gpt_h->sizeof_partition_entry));
gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
le32_to_cpu(gpt_h->header_size));
gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
/* Write the First GPT to the block right after the Legacy MBR */
if (dev_desc->block_write(dev_desc->dev, 1, 1, gpt_h) != 1)
goto err;
if (dev_desc->block_write(dev_desc->dev, 2, pte_blk_cnt, gpt_e)
!= pte_blk_cnt)
goto err;
prepare_backup_gpt_header(gpt_h);
if (dev_desc->block_write(dev_desc->dev,
(lbaint_t)le64_to_cpu(gpt_h->last_usable_lba)
+ 1,
pte_blk_cnt, gpt_e) != pte_blk_cnt)
goto err;
if (dev_desc->block_write(dev_desc->dev,
(lbaint_t)le64_to_cpu(gpt_h->my_lba), 1,
gpt_h) != 1)
goto err;
debug("GPT successfully written to block device!\n");
return 0;
err:
printf("** Can't write to device %d **\n", dev_desc->dev);
return -1;
}
int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
disk_partition_t *partitions, int parts)
{
lbaint_t offset = (lbaint_t)le64_to_cpu(gpt_h->first_usable_lba);
lbaint_t start;
lbaint_t last_usable_lba = (lbaint_t)
le64_to_cpu(gpt_h->last_usable_lba);
int i, k;
size_t efiname_len, dosname_len;
#ifdef CONFIG_PARTITION_UUIDS
char *str_uuid;
unsigned char *bin_uuid;
#endif
for (i = 0; i < parts; i++) {
/* partition starting lba */
start = partitions[i].start;
if (start && (start < offset)) {
printf("Partition overlap\n");
return -1;
}
if (start) {
gpt_e[i].starting_lba = cpu_to_le64(start);
offset = start + partitions[i].size;
} else {
gpt_e[i].starting_lba = cpu_to_le64(offset);
offset += partitions[i].size;
}
if (offset >= last_usable_lba) {
printf("Partitions layout exceds disk size\n");
return -1;
}
/* partition ending lba */
if ((i == parts - 1) && (partitions[i].size == 0))
/* extend the last partition to maximuim */
gpt_e[i].ending_lba = gpt_h->last_usable_lba;
else
gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
/* partition type GUID */
memcpy(gpt_e[i].partition_type_guid.b,
&PARTITION_BASIC_DATA_GUID, 16);
#ifdef CONFIG_PARTITION_UUIDS
str_uuid = partitions[i].uuid;
bin_uuid = gpt_e[i].unique_partition_guid.b;
if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_STD)) {
printf("Partition no. %d: invalid guid: %s\n",
i, str_uuid);
return -1;
}
#endif
/* partition attributes */
memset(&gpt_e[i].attributes, 0,
sizeof(gpt_entry_attributes));
/* partition name */
efiname_len = sizeof(gpt_e[i].partition_name)
/ sizeof(efi_char16_t);
dosname_len = sizeof(partitions[i].name);
memset(gpt_e[i].partition_name, 0,
sizeof(gpt_e[i].partition_name));
for (k = 0; k < min(dosname_len, efiname_len); k++)
gpt_e[i].partition_name[k] =
(efi_char16_t)(partitions[i].name[k]);
debug("%s: name: %s offset[%d]: 0x" LBAF
" size[%d]: 0x" LBAF "\n",
__func__, partitions[i].name, i,
offset, i, partitions[i].size);
}
return 0;
}
int gpt_fill_header(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
char *str_guid, int parts_count)
{
gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
gpt_h->my_lba = cpu_to_le64(1);
gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
gpt_h->first_usable_lba = cpu_to_le64(34);
gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
gpt_h->partition_entry_lba = cpu_to_le64(2);
gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
gpt_h->header_crc32 = 0;
gpt_h->partition_entry_array_crc32 = 0;
if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
return -1;
return 0;
}
int gpt_restore(block_dev_desc_t *dev_desc, char *str_disk_guid,
disk_partition_t *partitions, int parts_count)
{
int ret;
gpt_header *gpt_h = calloc(1, PAD_TO_BLOCKSIZE(sizeof(gpt_header),
dev_desc));
gpt_entry *gpt_e;
if (gpt_h == NULL) {
printf("%s: calloc failed!\n", __func__);
return -1;
}
gpt_e = calloc(1, PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS
* sizeof(gpt_entry),
dev_desc));
if (gpt_e == NULL) {
printf("%s: calloc failed!\n", __func__);
free(gpt_h);
return -1;
}
/* Generate Primary GPT header (LBA1) */
ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
if (ret)
goto err;
/* Generate partition entries */
ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count);
if (ret)
goto err;
/* Write GPT partition table */
ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
err:
free(gpt_e);
free(gpt_h);
return ret;
}
int is_valid_gpt_buf(block_dev_desc_t *dev_desc, void *buf)
{
gpt_header *gpt_h;
gpt_entry *gpt_e;
/* determine start of GPT Header in the buffer */
gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
dev_desc->blksz);
if (validate_gpt_header(gpt_h, GPT_PRIMARY_PARTITION_TABLE_LBA,
dev_desc->lba))
return -1;
/* determine start of GPT Entries in the buffer */
gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
dev_desc->blksz);
if (validate_gpt_entries(gpt_h, gpt_e))
return -1;
return 0;
}
int write_mbr_and_gpt_partitions(block_dev_desc_t *dev_desc, void *buf)
{
gpt_header *gpt_h;
gpt_entry *gpt_e;
int gpt_e_blk_cnt;
lbaint_t lba;
int cnt;
if (is_valid_gpt_buf(dev_desc, buf))
return -1;
/* determine start of GPT Header in the buffer */
gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
dev_desc->blksz);
/* determine start of GPT Entries in the buffer */
gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
dev_desc->blksz);
gpt_e_blk_cnt = BLOCK_CNT((le32_to_cpu(gpt_h->num_partition_entries) *
le32_to_cpu(gpt_h->sizeof_partition_entry)),
dev_desc);
/* write MBR */
lba = 0; /* MBR is always at 0 */
cnt = 1; /* MBR (1 block) */
if (dev_desc->block_write(dev_desc->dev, lba, cnt, buf) != cnt) {
printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
__func__, "MBR", cnt, lba);
return 1;
}
/* write Primary GPT */
lba = GPT_PRIMARY_PARTITION_TABLE_LBA;
cnt = 1; /* GPT Header (1 block) */
if (dev_desc->block_write(dev_desc->dev, lba, cnt, gpt_h) != cnt) {
printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
__func__, "Primary GPT Header", cnt, lba);
return 1;
}
lba = le64_to_cpu(gpt_h->partition_entry_lba);
cnt = gpt_e_blk_cnt;
if (dev_desc->block_write(dev_desc->dev, lba, cnt, gpt_e) != cnt) {
printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
__func__, "Primary GPT Entries", cnt, lba);
return 1;
}
prepare_backup_gpt_header(gpt_h);
/* write Backup GPT */
lba = le64_to_cpu(gpt_h->partition_entry_lba);
cnt = gpt_e_blk_cnt;
if (dev_desc->block_write(dev_desc->dev, lba, cnt, gpt_e) != cnt) {
printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
__func__, "Backup GPT Entries", cnt, lba);
return 1;
}
lba = le64_to_cpu(gpt_h->my_lba);
cnt = 1; /* GPT Header (1 block) */
if (dev_desc->block_write(dev_desc->dev, lba, cnt, gpt_h) != cnt) {
printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
__func__, "Backup GPT Header", cnt, lba);
return 1;
}
return 0;
}
#endif
/*
* Private functions
*/
/*
* pmbr_part_valid(): Check for EFI partition signature
*
* Returns: 1 if EFI GPT partition type is found.
*/
static int pmbr_part_valid(struct partition *part)
{
if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
get_unaligned_le32(&part->start_sect) == 1UL) {
return 1;
}
return 0;
}
/*
* is_pmbr_valid(): test Protective MBR for validity
*
* Returns: 1 if PMBR is valid, 0 otherwise.
* Validity depends on two things:
* 1) MSDOS signature is in the last two bytes of the MBR
* 2) One partition of type 0xEE is found, checked by pmbr_part_valid()
*/
static int is_pmbr_valid(legacy_mbr * mbr)
{
int i = 0;
if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
return 0;
for (i = 0; i < 4; i++) {
if (pmbr_part_valid(&mbr->partition_record[i])) {
return 1;
}
}
return 0;
}
/**
* is_gpt_valid() - tests one GPT header and PTEs for validity
*
* lba is the logical block address of the GPT header to test
* gpt is a GPT header ptr, filled on return.
* ptes is a PTEs ptr, filled on return.
*
* Description: returns 1 if valid, 0 on error.
* If valid, returns pointers to PTEs.
*/
static int is_gpt_valid(block_dev_desc_t *dev_desc, u64 lba,
gpt_header *pgpt_head, gpt_entry **pgpt_pte)
{
if (!dev_desc || !pgpt_head) {
printf("%s: Invalid Argument(s)\n", __func__);
return 0;
}
/* Read GPT Header from device */
if (dev_desc->block_read(dev_desc->dev, (lbaint_t)lba, 1, pgpt_head)
!= 1) {
printf("*** ERROR: Can't read GPT header ***\n");
return 0;
}
if (validate_gpt_header(pgpt_head, (lbaint_t)lba, dev_desc->lba))
return 0;
/* Read and allocate Partition Table Entries */
*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
if (*pgpt_pte == NULL) {
printf("GPT: Failed to allocate memory for PTE\n");
return 0;
}
if (validate_gpt_entries(pgpt_head, *pgpt_pte)) {
free(*pgpt_pte);
return 0;
}
/* We're done, all's well */
return 1;
}
/**
* alloc_read_gpt_entries(): reads partition entries from disk
* @dev_desc
* @gpt - GPT header
*
* Description: Returns ptes on success, NULL on error.
* Allocates space for PTEs based on information found in @gpt.
* Notes: remember to free pte when you're done!
*/
static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
gpt_header * pgpt_head)
{
size_t count = 0, blk_cnt;
gpt_entry *pte = NULL;
if (!dev_desc || !pgpt_head) {
printf("%s: Invalid Argument(s)\n", __func__);
return NULL;
}
count = le32_to_cpu(pgpt_head->num_partition_entries) *
le32_to_cpu(pgpt_head->sizeof_partition_entry);
debug("%s: count = %u * %u = %zu\n", __func__,
(u32) le32_to_cpu(pgpt_head->num_partition_entries),
(u32) le32_to_cpu(pgpt_head->sizeof_partition_entry), count);
/* Allocate memory for PTE, remember to FREE */
if (count != 0) {
pte = memalign(ARCH_DMA_MINALIGN,
PAD_TO_BLOCKSIZE(count, dev_desc));
}
if (count == 0 || pte == NULL) {
printf("%s: ERROR: Can't allocate 0x%zX "
"bytes for GPT Entries\n",
__func__, count);
return NULL;
}
/* Read GPT Entries from device */
blk_cnt = BLOCK_CNT(count, dev_desc);
if (dev_desc->block_read (dev_desc->dev,
(lbaint_t)le64_to_cpu(pgpt_head->partition_entry_lba),
(lbaint_t) (blk_cnt), pte)
!= blk_cnt) {
printf("*** ERROR: Can't read GPT Entries ***\n");
free(pte);
return NULL;
}
return pte;
}
/**
* is_pte_valid(): validates a single Partition Table Entry
* @gpt_entry - Pointer to a single Partition Table Entry
*
* Description: returns 1 if valid, 0 on error.
*/
static int is_pte_valid(gpt_entry * pte)
{
efi_guid_t unused_guid;
if (!pte) {
printf("%s: Invalid Argument(s)\n", __func__);
return 0;
}
/* Only one validation for now:
* The GUID Partition Type != Unused Entry (ALL-ZERO)
*/
memset(unused_guid.b, 0, sizeof(unused_guid.b));
if (memcmp(pte->partition_type_guid.b, unused_guid.b,
sizeof(unused_guid.b)) == 0) {
debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
(unsigned int)(uintptr_t)pte);
return 0;
} else {
return 1;
}
}
#endif