/*
* Copyright (C) 2007 Karel Zak <kzak@redhat.com>
* Copyright (C) 2012 Davidlohr Bueso <dave@gnu.org>
*
* GUID Partition Table (GPT) support. Based on UEFI Specs 2.3.1
* Chapter 5: GUID Partition Table (GPT) Disk Layout (Jun 27th, 2012).
* Some ideas and inspiration from GNU parted and gptfdisk.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <inttypes.h>
#include <sys/stat.h>
#include <sys/utsname.h>
#include <sys/types.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <ctype.h>
#include <uuid.h>
#include "nls.h"
#include "xalloc.h"
#include "common.h"
#include "fdisk.h"
#include "crc32.h"
#include "gpt.h"
#include "blkdev.h"
#include "bitops.h"
#include "strutils.h"
#define GPT_HEADER_SIGNATURE 0x5452415020494645LL /* EFI PART */
#define GPT_HEADER_REVISION_V1_02 0x00010200
#define GPT_HEADER_REVISION_V1_00 0x00010000
#define GPT_HEADER_REVISION_V0_99 0x00009900
#define GPT_PMBR_LBA 0
#define GPT_MBR_PROTECTIVE 1
#define GPT_MBR_HYBRID 2
#define GPT_PRIMARY_PARTITION_TABLE_LBA 0x00000001
#define EFI_PMBR_OSTYPE 0xEE
#define MSDOS_MBR_SIGNATURE 0xAA55
#define GPT_PART_NAME_LEN 72 / sizeof(uint16_t)
/* Globally unique identifier */
struct gpt_guid {
uint32_t time_low;
uint16_t time_mid;
uint16_t time_hi_and_version;
uint8_t clock_seq_hi;
uint8_t clock_seq_low;
uint8_t node[6];
};
/* only checking that the GUID is 0 is enough to verify an empty partition. */
#define GPT_UNUSED_ENTRY_GUID \
((struct gpt_guid) { 0x00000000, 0x0000, 0x0000, 0x00, 0x00, \
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }})
/* Linux native partition type */
#define GPT_DEFAULT_ENTRY_GUID \
((struct gpt_guid) { 0x0FC63DAF, 0x8483, 0x4772, 0x8E, 0x79, \
{ 0x3D, 0x69, 0xD8, 0x47, 0x7D, 0xE4 }})
/*
* Attribute bits
*/
struct gpt_attr {
uint64_t required_to_function:1;
uint64_t no_blockio_protocol:1;
uint64_t legacy_bios_bootable:1;
uint64_t reserved:45;
uint64_t guid_secific:16;
} __attribute__ ((packed));
/* The GPT Partition entry array contains an array of GPT entries. */
struct gpt_entry {
struct gpt_guid partition_type_guid; /* purpose and type of the partition */
struct gpt_guid unique_partition_guid;
uint64_t lba_start;
uint64_t lba_end;
struct gpt_attr attr;
uint16_t partition_name[GPT_PART_NAME_LEN];
} __attribute__ ((packed));
/* GPT header */
struct gpt_header {
uint64_t signature; /* header identification */
uint32_t revision; /* header version */
uint32_t size; /* in bytes */
uint32_t crc32; /* header CRC checksum */
uint32_t reserved1; /* must be 0 */
uint64_t my_lba; /* LBA that contains this struct (LBA 1) */
uint64_t alternative_lba; /* backup GPT header */
uint64_t first_usable_lba; /* first usable logical block for partitions */
uint64_t last_usable_lba; /* last usable logical block for partitions */
struct gpt_guid disk_guid; /* unique disk identifier */
uint64_t partition_entry_lba; /* stat LBA of the partition entry array */
uint32_t npartition_entries; /* total partition entries - normally 128 */
uint32_t sizeof_partition_entry; /* bytes for each GUID pt */
uint32_t partition_entry_array_crc32; /* partition CRC checksum */
uint8_t reserved2[512 - 92]; /* must be 0 */
} __attribute__ ((packed));
struct gpt_record {
uint8_t boot_indicator; /* unused by EFI, set to 0x80 for bootable */
uint8_t start_head; /* unused by EFI, pt start in CHS */
uint8_t start_sector; /* unused by EFI, pt start in CHS */
uint8_t start_track;
uint8_t os_type; /* EFI and legacy non-EFI OS types */
uint8_t end_head; /* unused by EFI, pt end in CHS */
uint8_t end_sector; /* unused by EFI, pt end in CHS */
uint8_t end_track; /* unused by EFI, pt end in CHS */
uint32_t starting_lba; /* used by EFI - start addr of the on disk pt */
uint32_t size_in_lba; /* used by EFI - size of pt in LBA */
} __attribute__ ((packed));
/* Protected MBR and legacy MBR share same structure */
struct gpt_legacy_mbr {
uint8_t boot_code[440];
uint32_t unique_mbr_signature;
uint16_t unknown;
struct gpt_record partition_record[4];
uint16_t signature;
} __attribute__ ((packed));
/*
* Here be dragons!
* See: http://en.wikipedia.org/wiki/GUID_Partition_Table#Partition_type_GUIDs
*/
#define DEF_GUID(_u, _n) \
{ \
.typestr = (_u), \
.name = (_n), \
}
static struct fdisk_parttype gpt_parttypes[] =
{
/* Generic OS */
DEF_GUID("C12A7328-F81F-11D2-BA4B-00A0C93EC93B", N_("EFI System")),
DEF_GUID("024DEE41-33E7-11D3-9D69-0008C781F39F", N_("MBR partition scheme")),
/* Hah!IdontneedEFI */
DEF_GUID("21686148-6449-6E6F-744E-656564454649", N_("BIOS boot partition")),
/* Windows */
DEF_GUID("E3C9E316-0B5C-4DB8-817D-F92DF00215AE", N_("Microsoft reserved")),
DEF_GUID("EBD0A0A2-B9E5-4433-87C0-68B6B72699C7", N_("Microsoft basic data")),
DEF_GUID("5808C8AA-7E8F-42E0-85D2-E1E90434CFB3", N_("Microsoft LDM metadata")),
DEF_GUID("AF9B60A0-1431-4F62-BC68-3311714A69AD", N_("Microsoft LDM data")),
DEF_GUID("DE94BBA4-06D1-4D40-A16A-BFD50179D6AC", N_("Windows recovery evironmnet")),
DEF_GUID("37AFFC90-EF7D-4E96-91C3-2D7AE055B174", N_("IBM General Parallel Fs")),
/* HP-UX */
DEF_GUID("75894C1E-3AEB-11D3-B7C1-7B03A0000000", N_("HP-UX data partition")),
DEF_GUID("E2A1E728-32E3-11D6-A682-7B03A0000000", N_("HP-UX service partition")),
/* Linux */
DEF_GUID("0FC63DAF-8483-4772-8E79-3D69D8477DE4", N_("Linux filesystem")),
DEF_GUID("A19D880F-05FC-4D3B-A006-743F0F84911E", N_("Linux RAID")),
DEF_GUID("0657FD6D-A4AB-43C4-84E5-0933C84B4F4F", N_("Linux swap")),
DEF_GUID("E6D6D379-F507-44C2-A23C-238F2A3DF928", N_("Linux LVM")),
DEF_GUID("8DA63339-0007-60C0-C436-083AC8230908", N_("Linux reserved")),
/* FreeBSD */
DEF_GUID("516E7CB4-6ECF-11D6-8FF8-00022D09712B", N_("FreeBSD data")),
DEF_GUID("83BD6B9D-7F41-11DC-BE0B-001560B84F0F", N_("FreeBSD boot")),
DEF_GUID("516E7CB5-6ECF-11D6-8FF8-00022D09712B", N_("FreeBSD swap")),
DEF_GUID("516E7CB6-6ECF-11D6-8FF8-00022D09712B", N_("FreeBSD UFS")),
DEF_GUID("516E7CBA-6ECF-11D6-8FF8-00022D09712B", N_("FreeBSD ZFS")),
DEF_GUID("516E7CB8-6ECF-11D6-8FF8-00022D09712B", N_("FreeBSD Vinum")),
/* Apple OSX */
DEF_GUID("48465300-0000-11AA-AA11-00306543ECAC", N_("Apple HFS/HFS+")),
DEF_GUID("55465300-0000-11AA-AA11-00306543ECAC", N_("Apple UFS")),
DEF_GUID("52414944-0000-11AA-AA11-00306543ECAC", N_("Apple RAID")),
DEF_GUID("52414944-5F4F-11AA-AA11-00306543ECAC", N_("Apple RAID offline")),
DEF_GUID("426F6F74-0000-11AA-AA11-00306543ECAC", N_("Apple boot")),
DEF_GUID("4C616265-6C00-11AA-AA11-00306543ECAC", N_("Apple label")),
DEF_GUID("5265636F-7665-11AA-AA11-00306543ECAC", N_("Apple TV recovery")),
DEF_GUID("53746F72-6167-11AA-AA11-00306543ECAC", N_("Apple Core storage")),
/* Solaris */
DEF_GUID("6A82CB45-1DD2-11B2-99A6-080020736631", N_("Solaris boot")),
DEF_GUID("6A85CF4D-1DD2-11B2-99A6-080020736631", N_("Solaris root")),
/* same as Apple ZFS */
DEF_GUID("6A898CC3-1DD2-11B2-99A6-080020736631", N_("Solaris /usr & Apple ZFS")),
DEF_GUID("6A87C46F-1DD2-11B2-99A6-080020736631", N_("Solaris swap")),
DEF_GUID("6A8B642B-1DD2-11B2-99A6-080020736631", N_("Solaris backup")),
DEF_GUID("6A8EF2E9-1DD2-11B2-99A6-080020736631", N_("Solaris /var")),
DEF_GUID("6A90BA39-1DD2-11B2-99A6-080020736631", N_("Solaris /home")),
DEF_GUID("6A9283A5-1DD2-11B2-99A6-080020736631", N_("Solaris alternate sector")),
DEF_GUID("6A945A3B-1DD2-11B2-99A6-080020736631", N_("Solaris reserved 1")),
DEF_GUID("6A9630D1-1DD2-11B2-99A6-080020736631", N_("Solaris reserved 2")),
DEF_GUID("6A980767-1DD2-11B2-99A6-080020736631", N_("Solaris reserved 3")),
DEF_GUID("6A96237F-1DD2-11B2-99A6-080020736631", N_("Solaris reserved 4")),
DEF_GUID("6A8D2AC7-1DD2-11B2-99A6-080020736631", N_("Solaris reserved 5")),
/* NetBSD */
DEF_GUID("49F48D32-B10E-11DC-B99B-0019D1879648", N_("NetBSD swap")),
DEF_GUID("49F48D5A-B10E-11DC-B99B-0019D1879648", N_("NetBSD FFS")),
DEF_GUID("49F48D82-B10E-11DC-B99B-0019D1879648", N_("NetBSD LFS")),
DEF_GUID("2DB519C4-B10E-11DC-B99B-0019D1879648", N_("NetBSD concatenated")),
DEF_GUID("2DB519EC-B10E-11DC-B99B-0019D1879648", N_("NetBSD encrypted")),
DEF_GUID("49F48DAA-B10E-11DC-B99B-0019D1879648", N_("NetBSD RAID")),
/* ChromeOS */
DEF_GUID("FE3A2A5D-4F32-41A7-B725-ACCC3285A309", N_("ChromeOS kernel")),
DEF_GUID("3CB8E202-3B7E-47DD-8A3C-7FF2A13CFCEC", N_("ChromeOS root fs")),
DEF_GUID("2E0A753D-9E48-43B0-8337-B15192CB1B5E", N_("ChromeOS reserved")),
/* MidnightBSD */
DEF_GUID("85D5E45A-237C-11E1-B4B3-E89A8F7FC3A7", N_("MidnightBSD data")),
DEF_GUID("85D5E45E-237C-11E1-B4B3-E89A8F7FC3A7", N_("MidnightBSD boot")),
DEF_GUID("85D5E45B-237C-11E1-B4B3-E89A8F7FC3A7", N_("MidnightBSD swap")),
DEF_GUID("0394Ef8B-237C-11E1-B4B3-E89A8F7FC3A7", N_("MidnightBSD UFS")),
DEF_GUID("85D5E45D-237C-11E1-B4B3-E89A8F7FC3A7", N_("MidnightBSD ZFS")),
DEF_GUID("85D5E45C-237C-11E1-B4B3-E89A8F7FC3A7", N_("MidnightBSD Vinum")),
};
/* primary GPT header */
static struct gpt_header *pheader = NULL;
/* backup GPT header */
static struct gpt_header *bheader = NULL;
/* partition entry array */
static struct gpt_entry *ents = NULL;
/*
* UUID is traditionally 16 byte big-endian array, except Intel EFI
* specification where the UUID is a structure of little-endian fields.
*/
static void swap_efi_guid(struct gpt_guid *uid)
{
uid->time_low = swab32(uid->time_low);
uid->time_mid = swab16(uid->time_mid);
uid->time_hi_and_version = swab16(uid->time_hi_and_version);
}
static int string_to_uuid(const char *in, struct gpt_guid *uuid)
{
if (uuid_parse(in, (unsigned char *) uuid))
return -1;
swap_efi_guid(uuid);
return 0;
}
static void uuid_to_string(struct gpt_guid *uuid, char *out)
{
uuid_unparse_upper((unsigned char *) uuid, out);
}
static const char *gpt_get_header_revstr(struct gpt_header *header)
{
if (!header)
goto unknown;
switch (header->revision) {
case GPT_HEADER_REVISION_V1_02:
return "1.2";
case GPT_HEADER_REVISION_V1_00:
return "1.0";
case GPT_HEADER_REVISION_V0_99:
return "0.99";
default:
goto unknown;
}
unknown:
return "unknown";
}
static inline int partition_unused(struct gpt_entry e)
{
return !memcmp(&e.partition_type_guid, &GPT_UNUSED_ENTRY_GUID,
sizeof(struct gpt_guid));
}
/*
* Checks if there is a valid protective MBR partition table.
* Returns 0 if it is invalid or failure. Otherwise, return
* GPT_MBR_PROTECTIVE or GPT_MBR_HYBRID, depeding on the detection.
*/
static int valid_pmbr(struct fdisk_context *cxt)
{
int i, ret = 0; /* invalid by default */
struct gpt_legacy_mbr *pmbr = NULL;
if (!cxt->firstsector)
goto done;
pmbr = (struct gpt_legacy_mbr *) cxt->firstsector;
if (pmbr->signature != cpu_to_le64(MSDOS_MBR_SIGNATURE))
goto done;
/* LBA of the GPT partition header */
if (pmbr->partition_record[0].starting_lba !=
cpu_to_le32(GPT_PRIMARY_PARTITION_TABLE_LBA))
goto done;
/* seems like a valid MBR was found, check DOS primary partitions */
for (i = 0; i < 4; i++)
if (pmbr->partition_record[i].os_type == EFI_PMBR_OSTYPE) {
/*
* Ok, we at least know that there's a protective MBR,
* now check if there are other partition types for
* hybrid MBR.
*/
ret = GPT_MBR_PROTECTIVE;
goto check_hybrid;
}
check_hybrid:
if (ret != GPT_MBR_PROTECTIVE)
goto done;
for (i = 0 ; i < 4; i++)
if ((pmbr->partition_record[i].os_type != EFI_PMBR_OSTYPE) &&
(pmbr->partition_record[i].os_type != 0x00))
ret = GPT_MBR_HYBRID;
/*
* Protective MBRs take up the lesser of the whole disk
* or 2 TiB (32bit LBA), ignoring the rest of the disk.
*
* Hybrid MBRs do not necessarily comply with this.
*/
if (ret == GPT_MBR_PROTECTIVE)
if (pmbr->partition_record[0].size_in_lba !=
cpu_to_le32(min((uint32_t) cxt->total_sectors - 1, 0xFFFFFFFF)))
ret = 0;
done:
return ret;
}
static uint64_t last_lba(struct fdisk_context *cxt)
{
struct stat s;
memset(&s, 0, sizeof(s));
if (fstat(cxt->dev_fd, &s) == -1) {
fprintf(stderr, "last_lba() could not stat: %m\n");
return 0;
}
if (S_ISBLK(s.st_mode))
return cxt->total_sectors - 1;
else if (S_ISREG(s.st_mode)) {
uint64_t sectors = s.st_size >> cxt->sector_size;
return (sectors / cxt->sector_size) - 1ULL;
} else {
fprintf(stderr,
"last_lba(): I don't know how to handle files with mode %o\n",
s.st_mode);
}
return 0;
}
static ssize_t read_lba(struct fdisk_context *cxt, uint64_t lba,
void *buffer, const size_t bytes)
{
off_t offset = lba * cxt->sector_size;
lseek(cxt->dev_fd, offset, SEEK_SET);
return read(cxt->dev_fd, buffer, bytes);
}
/* Returns the GPT entry array */
static struct gpt_entry *gpt_get_entries(struct fdisk_context *cxt,
struct gpt_header *header, const ssize_t sz)
{
struct gpt_entry *ret = xcalloc(1, sizeof(*ents) * sz);
off_t offset = le64_to_cpu(header->partition_entry_lba) *
cxt->sector_size;
if (offset != lseek(cxt->dev_fd, offset, SEEK_SET))
return NULL;
if (sz != read(cxt->dev_fd, ret, sz))
return NULL;
return ret;
}
static inline uint32_t count_crc32(const unsigned char *buf, size_t len)
{
return (crc32(~0L, buf, len) ^ ~0L);
}
/*
* Recompute header and partition array 32bit CRC checksums.
* This function does not fail - if there's corruption, then it
* will be reported when checksuming it again (ie: probing or verify).
*/
static void gpt_recompute_crc(struct gpt_header *header, struct gpt_entry *e)
{
uint32_t crc = 0;
size_t entry_sz = 0;
if (!header)
return;
/* header CRC */
header->crc32 = 0;
crc = count_crc32((unsigned char *) header, le32_to_cpu(header->size));
header->crc32 = cpu_to_le32(crc);
/* partition entry array CRC */
header->partition_entry_array_crc32 = 0;
entry_sz = le32_to_cpu(header->npartition_entries) *
le32_to_cpu(header->sizeof_partition_entry);
crc = count_crc32((unsigned char *) e, entry_sz);
header->partition_entry_array_crc32 = cpu_to_le32(crc);
}
/*
* Compute the 32bit CRC checksum of the partition table header.
* Returns 1 if it is valid, otherwise 0.
*/
static int gpt_check_header_crc(struct gpt_header *header)
{
uint32_t crc, orgcrc = le32_to_cpu(header->crc32);
header->crc32 = 0;
crc = count_crc32((unsigned char *) header, le32_to_cpu(header->size));
header->crc32 = cpu_to_le32(orgcrc);
/*
* If we have checksum mismatch it may be due to stale data,
* like a partition being added or deleted. Recompute the CRC again
* and make sure this is not the case.
*/
if (crc != le32_to_cpu(header->crc32)) {
gpt_recompute_crc(header, ents);
orgcrc = le32_to_cpu(header->crc32);
header->crc32 = 0;
crc = count_crc32((unsigned char *) header, le32_to_cpu(header->size));
header->crc32 = cpu_to_le32(orgcrc);
return crc == le32_to_cpu(header->crc32);
} else
return 1;
}
/*
* It initializes the partition entry array.
* Returns 1 if the checksum is valid, otherwise 0.
*/
static int gpt_check_entryarr_crc(struct fdisk_context *cxt, struct gpt_header *header)
{
int ret = 0;
ssize_t entry_sz;
uint32_t crc;
if (!header)
goto done;
entry_sz = le32_to_cpu(header->npartition_entries) *
le32_to_cpu(header->sizeof_partition_entry);
if (!entry_sz)
goto done;
/* read header entries */
if (!ents)
ents = gpt_get_entries(cxt, header, entry_sz);
if (!ents)
goto done;
crc = count_crc32((unsigned char *) ents, entry_sz);
ret = (crc == le32_to_cpu(header->partition_entry_array_crc32));
done:
return ret;
}
static int gpt_check_lba_sanity(struct fdisk_context *cxt, struct gpt_header *header)
{
int ret = 0;
uint64_t lu, fu, lastlba = last_lba(cxt);
fu = le64_to_cpu(header->first_usable_lba);
lu = le64_to_cpu(header->last_usable_lba);
/* check if first and last usable LBA make sense */
if (lu < fu) {
DBG(LABEL, dbgprint("error: header last LBA is before first LBA"));
goto done;
}
/* check if first and last usable LBAs with the disk's last LBA */
if (fu > lastlba || lu > lastlba) {
DBG(LABEL, dbgprint("error: header LBAs are after the disk's last LBA"));
goto done;
}
/* the header has to be outside usable range */
if (fu < GPT_PRIMARY_PARTITION_TABLE_LBA &&
GPT_PRIMARY_PARTITION_TABLE_LBA < lu) {
DBG(LABEL, dbgprint("error: header outside of usable range"));
goto done;
}
ret = 1; /* sane */
done:
return ret;
}
/* Check if there is a valid header signature */
static int gpt_check_signature(struct gpt_header *header)
{
return header->signature == cpu_to_le64(GPT_HEADER_SIGNATURE);
}
/*
* Return the specified GPT Header, or NULL upon failure/invalid.
* Note that all tests must pass to ensure a valid header,
* we do not rely on only testing the signature for a valid probe.
*/
static struct gpt_header *gpt_get_header(struct fdisk_context *cxt, uint64_t lba)
{
struct gpt_header *header = NULL;
if (!cxt)
return NULL;
header = xcalloc(1, sizeof(*header));
/* read specified LBA */
if (!read_lba(cxt, lba, header, sizeof(struct gpt_header)))
goto invalid;
if (!gpt_check_signature(header))
goto invalid;
if (!gpt_check_header_crc(header) ||
!gpt_check_entryarr_crc(cxt, header))
goto invalid;
if (!gpt_check_lba_sanity(cxt, header))
goto invalid;
/* valid header must be at MyLBA */
if (le64_to_cpu(header->my_lba) != lba)
goto invalid;
return header;
invalid:
free(header);
return NULL;
}
/*
* Return the Backup GPT Header, or NULL upon failure/invalid.
*/
static struct gpt_header *gpt_get_bheader(struct fdisk_context *cxt)
{
return gpt_get_header(cxt, last_lba(cxt));
}
/*
* Return the Primary GPT Header, or NULL upon failure/invalid.
*/
static struct gpt_header *gpt_get_pheader(struct fdisk_context *cxt)
{
return gpt_get_header(cxt, GPT_PRIMARY_PARTITION_TABLE_LBA);
}
/*
* Returns the number of partitions that are in use.
*/
static uint32_t partitions_in_use(struct gpt_header *header, struct gpt_entry *e)
{
uint32_t i, used = 0;
if (!header || ! e)
return 0;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++)
if (!partition_unused(e[i]))
used++;
return used;
}
/*
* Returns the partition length, or 0 if end is before beginning.
*/
static uint64_t partition_size(struct gpt_entry e)
{
uint64_t start = le64_to_cpu(e.lba_start);
uint64_t end = le64_to_cpu(e.lba_end);
return start > end ? 0 : end - start + 1ULL;
}
/*
* Check if a partition is too big for the disk (sectors).
* Returns the faulting partition number, otherwise 0.
*/
static int partition_check_too_big(struct gpt_header *header,
struct gpt_entry *e, uint64_t sectors)
{
uint32_t i;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (partition_unused(e[i]))
continue;
if (e[i].lba_end >= sectors)
return i + 1;
}
return 0;
}
/*
* Check if a partition ends before it begins
* Returns the faulting partition number, otherwise 0.
*/
static int partition_start_after_end(struct gpt_header *header, struct gpt_entry *e)
{
uint32_t i;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (partition_unused(e[i]))
continue;
if (e[i].lba_start > e[i].lba_end)
return i + 1;
}
return 0;
}
/*
* Check if partition e1 overlaps with partition e2
*/
static inline int partition_overlap(struct gpt_entry e1, struct gpt_entry e2)
{
return (e1.lba_start && e2.lba_start &&
(e1.lba_start <= e2.lba_end) != (e1.lba_end < e2.lba_start));
}
/*
* Find any paritions that overlap.
*/
static int partition_check_overlaps(struct gpt_header *header, struct gpt_entry *e)
{
uint32_t i, j;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++)
for (j = 0; j < i; j++) {
if (partition_unused(e[i]) ||
partition_unused(e[j]))
continue;
if (partition_overlap(e[i], e[j]))
/* two overlaping partitions is enough! */
return i + 1;
}
return 0;
}
/*
* Find the first available block after the starting point; returns 0 if
* there are no available blocks left, or error. From gdisk.
*/
static uint64_t find_first_available(struct gpt_header *header,
struct gpt_entry *e, uint64_t start)
{
uint64_t first;
uint32_t i, first_moved = 0;
if (!header || !e)
return 0;
/*
* Begin from the specified starting point or from the first usable
* LBA, whichever is greater...
*/
first = start < header->first_usable_lba ? header->first_usable_lba : start;
/*
* Now search through all partitions; if first is within an
* existing partition, move it to the next sector after that
* partition and repeat. If first was moved, set firstMoved
* flag; repeat until firstMoved is not set, so as to catch
* cases where partitions are out of sequential order....
*/
do {
first_moved = 0;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (partition_unused(e[i]))
continue;
if (first < e[i].lba_start)
continue;
if (first <= e[i].lba_end) {
first = e[i].lba_end + 1;
first_moved = 1;
}
}
} while (first_moved == 1);
if (first > header->last_usable_lba)
first = 0;
return first;
}
/* Returns last available sector in the free space pointed to by start. From gdisk. */
static uint64_t find_last_free(struct gpt_header *header,
struct gpt_entry *e, uint64_t start)
{
uint32_t i;
uint64_t nearest_start;
if (!header || !e)
return 0;
nearest_start = header->last_usable_lba;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if (nearest_start > e[i].lba_start &&
e[i].lba_start > start)
nearest_start = e[i].lba_start - 1;
}
return nearest_start;
}
/* Returns the last free sector on the disk. From gdisk. */
static uint64_t find_last_free_sector(struct gpt_header *header,
struct gpt_entry *e)
{
uint32_t i, last_moved;
uint64_t last = 0;
if (!header || !e)
goto done;
/* start by assuming the last usable LBA is available */
last = header->last_usable_lba;
do {
last_moved = 0;
for (i = 0; i < le32_to_cpu(header->npartition_entries); i++) {
if ((last >= e[i].lba_start) &&
(last <= e[i].lba_end)) {
last = e[i].lba_start - 1;
last_moved = 1;
}
}
} while (last_moved == 1);
done:
return last;
}
/*
* Finds the first available sector in the largest block of unallocated
* space on the disk. Returns 0 if there are no available blocks left.
* From gdisk.
*/
static uint64_t find_first_in_largest(struct gpt_header *header, struct gpt_entry *e)
{
uint64_t start = 0, first_sect, last_sect;
uint64_t segment_size, selected_size = 0, selected_segment = 0;
if (!header || !e)
goto done;
do {
first_sect = find_first_available(header, e, start);
if (first_sect != 0) {
last_sect = find_last_free(header, e, first_sect);
segment_size = last_sect - first_sect + 1;
if (segment_size > selected_size) {
selected_size = segment_size;
selected_segment = first_sect;
}
start = last_sect + 1;
}
} while (first_sect != 0);
done:
return selected_segment;
}
/*
* Find the total number of free sectors, the number of segments in which
* they reside, and the size of the largest of those segments. From gdisk.
*/
static uint64_t get_free_sectors(struct fdisk_context *cxt, struct gpt_header *header,
struct gpt_entry *e, uint32_t *nsegments,
uint64_t *largest_segment)
{
uint32_t num = 0;
uint64_t first_sect, last_sect;
uint64_t largest_seg = 0, segment_sz;
uint64_t totfound = 0, start = 0; /* starting point for each search */
if (!cxt->total_sectors)
goto done;
do {
first_sect = find_first_available(header, e, start);
if (first_sect) {
last_sect = find_last_free(header, e, first_sect);
segment_sz = last_sect - first_sect + 1;
if (segment_sz > largest_seg)
largest_seg = segment_sz;
totfound += segment_sz;
num++;
start = last_sect + 1;
}
} while (first_sect);
done:
*nsegments = num;
*largest_segment = largest_seg;
return totfound;
}
/*
* Initialize fdisk-specific variables - call once probing passes!
*/
static void gpt_init(void)
{
disklabel = GPT_LABEL;
partitions = le32_to_cpu(pheader->npartition_entries);
}
static int gpt_probe_label(struct fdisk_context *cxt)
{
int mbr_type;
if (!cxt)
goto failed;
mbr_type = valid_pmbr(cxt);
if (!mbr_type)
goto failed;
DBG(LABEL, dbgprint("found a %s MBR", mbr_type == GPT_MBR_PROTECTIVE ?
"protective" : "hybrid"));
pheader = gpt_get_pheader(cxt);
/*
* TODO: If the primary GPT is corrupt, we must check the last LBA of the
* device to see if it has a valid GPT Header and point to a valid GPT
* Partition Entry Array.
* If it points to a valid GPT Partition Entry Array, then software should
* restore the primary GPT if allowed by platform policy settings.
*
* For now we just abort GPT probing!
*/
if (!pheader)
goto failed;
/* OK, probing passed, now initialize backup header and fdisk variables. */
bheader = gpt_get_bheader(cxt);
gpt_init();
printf(_("\nWARNING: fdisk GPT support is currently new, and therefore "
"in an experimental phase. Use at your own discretion.\n\n"));
return 1;
failed:
return 0;
}
/*
* Stolen from libblkid - can be removed once partition semantics
* are added to the fdisk API.
*/
static char *encode_to_utf8(unsigned char *src, size_t count)
{
uint16_t c;
char *dest = xmalloc(count * sizeof(char));
size_t i, j, len = count;
memset(dest, 0, sizeof(char) * count);
for (j = i = 0; i + 2 <= count; i += 2) {
/* always little endian */
c = (src[i+1] << 8) | src[i];
if (c == 0) {
dest[j] = '\0';
break;
} else if (c < 0x80) {
if (j+1 >= len)
break;
dest[j++] = (uint8_t) c;
} else if (c < 0x800) {
if (j+2 >= len)
break;
dest[j++] = (uint8_t) (0xc0 | (c >> 6));
dest[j++] = (uint8_t) (0x80 | (c & 0x3f));
} else {
if (j+3 >= len)
break;
dest[j++] = (uint8_t) (0xe0 | (c >> 12));
dest[j++] = (uint8_t) (0x80 | ((c >> 6) & 0x3f));
dest[j++] = (uint8_t) (0x80 | (c & 0x3f));
}
}
dest[j] = '\0';
return dest;
}
/*
* List label partitions.
* This function must currently exist to comply with standard fdisk
* requirements, but once partition semantics are added to the fdisk
* API it can be removed for custom implementation (see gpt_label struct).
*/
void gpt_list_table(struct fdisk_context *cxt,
int xtra __attribute__ ((__unused__)))
{
uint32_t i;
uint64_t fu = le64_to_cpu(pheader->first_usable_lba);
uint64_t lu = le64_to_cpu(pheader->last_usable_lba);
printf("\n# Start End Size Type Name\n");
for (i = 0; i < le32_to_cpu(pheader->npartition_entries); i++) {
char *name = NULL, *sizestr = NULL;
uint64_t start = le64_to_cpu(ents[i].lba_start);
uint64_t size = partition_size(ents[i]);
struct fdisk_parttype *t;
if (partition_unused(ents[i]) || !size)
continue;
/* the partition has to inside usable range */
if (start < fu || start + size - 1 > lu)
continue;
name = encode_to_utf8((unsigned char *)ents[i].partition_name,
sizeof(ents[i].partition_name));
if (!name)
continue;
sizestr = size_to_human_string(SIZE_SUFFIX_1LETTER,
size * cxt->sector_size);
if (!sizestr)
continue;
t = fdisk_get_partition_type(cxt, i);
printf("%2d %12ld %12ld %6s %-15.15s %s\n",
i+1,
ents[i].lba_start,
ents[i].lba_end,
sizestr,
t->name,
name);
free(name);
free(sizestr);
fdisk_free_parttype(t);
}
}
/*
* Write partitions.
* Returns 0 on success, or corresponding error otherwise.
*/
static int gpt_write_partitions(struct fdisk_context *cxt,
struct gpt_header *header, struct gpt_entry *e)
{
off_t offset = le64_to_cpu(header->partition_entry_lba) * cxt->sector_size;
uint32_t nparts = le32_to_cpu(header->npartition_entries);
uint32_t totwrite = nparts * le32_to_cpu(header->sizeof_partition_entry);
if (offset != lseek(cxt->dev_fd, offset, SEEK_SET))
goto fail;
if (totwrite == write(cxt->dev_fd, e, totwrite))
return 0;
fail:
return -errno;
}
/*
* Write a GPT header to a specified LBA
* Returns 0 on success, or corresponding error otherwise.
*/
static int gpt_write_header(struct fdisk_context *cxt,
struct gpt_header *header, uint64_t lba)
{
off_t offset = lba * cxt->sector_size;
if (offset != lseek(cxt->dev_fd, offset, SEEK_SET))
goto fail;
if (cxt->sector_size ==
(size_t) write(cxt->dev_fd, header, cxt->sector_size))
return 0;
fail:
return -errno;
}
/*
* Write the protective MBR.
* Returns 0 on success, or corresponding error otherwise.
*/
static int gpt_write_pmbr(struct fdisk_context *cxt)
{
off_t offset;
struct gpt_legacy_mbr *pmbr = NULL;
if (!cxt || !cxt->firstsector)
return -EINVAL;
pmbr = (struct gpt_legacy_mbr *) cxt->firstsector;
/* zero out the legacy partitions */
memset(pmbr->partition_record, 0, sizeof(pmbr->partition_record));
pmbr->signature = cpu_to_le16(MSDOS_MBR_SIGNATURE);
pmbr->partition_record[0].os_type = EFI_PMBR_OSTYPE;
pmbr->partition_record[0].start_sector = 1;
pmbr->partition_record[0].end_head = 0xFE;
pmbr->partition_record[0].end_sector = 0xFF;
pmbr->partition_record[0].end_track = 0xFF;
pmbr->partition_record[0].starting_lba = cpu_to_le32(1);
/*
* Set size_in_lba to the size of the disk minus one. If the size of the disk
* is too large to be represented by a 32bit LBA (2Tb), set it to 0xFFFFFFFF.
*/
if (cxt->total_sectors - 1 > 0xFFFFFFFFULL)
pmbr->partition_record[0].size_in_lba = cpu_to_le32(0xFFFFFFFF);
else
pmbr->partition_record[0].size_in_lba =
cpu_to_le32(cxt->total_sectors - 1UL);
offset = GPT_PMBR_LBA * cxt->sector_size;
if (offset != lseek(cxt->dev_fd, offset, SEEK_SET))
goto fail;
if (1 == write(cxt->dev_fd, pmbr, 1))
return 0;
fail:
return -errno;
}
/*
* Writes in-memory GPT and pMBR data to disk.
* Returns 0 if successful write, otherwise, a corresponding error.
* Any indication of error will abort the operation.
*/
static int gpt_write_disklabel(struct fdisk_context *cxt)
{
if (!cxt)
goto err0;
/* we do not want to mess up hybrid MBRs by creating a valid pmbr */
if (valid_pmbr(cxt) == GPT_MBR_HYBRID)
goto err0;
/* check that disk is big enough to handle the backup header */
if (pheader->alternative_lba > cxt->total_sectors)
goto err0;
/* check that the backup header is properly placed */
if (pheader->alternative_lba < cxt->total_sectors - 1)
/* TODO: correct this (with user authorization) and write */
goto err0;
if (partition_check_overlaps(pheader, ents))
goto err0;
/* recompute CRCs for both headers */
gpt_recompute_crc(pheader, ents);
gpt_recompute_crc(bheader, ents);
/*
* UEFI requires writing in this specific order:
* 1) backup partition tables
* 2) backup GPT header
* 3) primary partition tables
* 4) primary GPT header
* 5) protective MBR
*
* If any write fails, we abort the rest.
*/
if (gpt_write_partitions(cxt, bheader, ents) != 0)
goto err1;
if (gpt_write_header(cxt, bheader, pheader->alternative_lba) != 0)
goto err1;
if (gpt_write_partitions(cxt, pheader, ents) != 0)
goto err1;
if (gpt_write_header(cxt, pheader, GPT_PRIMARY_PARTITION_TABLE_LBA) != 0)
goto err1;
if (gpt_write_pmbr(cxt) != 0)
goto err1;
return 0;
err0:
return -EINVAL;
err1:
return -errno;
}
/*
* Verify data integrity and report any found problems for:
* - primary and backup header validations
* - paritition validations
*/
static int gpt_verify_disklabel(struct fdisk_context *cxt)
{
int nerror = 0;
uint64_t ptnum;
if (!bheader) {
nerror++;
printf(_("Disk does not contain a valid backup header.\n"));
}
if (!gpt_check_header_crc(pheader)) {
nerror++;
printf(_("Invalid primary header CRC checksum.\n"));
}
if (bheader && !gpt_check_header_crc(bheader)) {
nerror++;
printf(_("Invalid backup header CRC checksum.\n"));
}
if (!gpt_check_entryarr_crc(cxt, pheader)) {
nerror++;
printf(_("Invalid partition entry checksum.\n"));
}
if (!gpt_check_lba_sanity(cxt, pheader)) {
nerror++;
printf(_("Invalid primary header LBA sanity checks.\n"));
}
if (bheader && !gpt_check_lba_sanity(cxt, bheader)) {
nerror++;
printf(_("Invalid backup header LBA sanity checks.\n"));
}
if (le64_to_cpu(pheader->my_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA) {
nerror++;
printf(_("MyLBA mismatch with real position at primary header.\n"));
}
if (bheader && le64_to_cpu(bheader->my_lba) != last_lba(cxt)) {
nerror++;
printf(_("MyLBA mismatch with real position at backup header.\n"));
}
if (pheader->alternative_lba >= cxt->total_sectors) {
nerror++;
printf(_("Disk is to small to hold all data.\n"));
}
/*
* if the GPT is the primary table, check the alternateLBA
* to see if it is a valid GPT
*/
if (bheader && (pheader->my_lba != bheader->alternative_lba)) {
nerror++;
printf(_("Primary and backup header mismatch.\n"));
}
ptnum = partition_check_overlaps(pheader, ents);
if (ptnum) {
nerror++;
printf(_("Partition %ld overlaps with partition %ld.\n"), ptnum, ptnum+1);
}
ptnum = partition_check_too_big(pheader, ents, cxt->total_sectors);
if (ptnum) {
nerror++;
printf(_("Partition %ld is too big for the disk.\n"), ptnum);
}
ptnum = partition_start_after_end(pheader, ents);
if (ptnum) {
nerror++;
printf(_("Partition %ld ends before it starts.\n"), ptnum);
}
if (!nerror) { /* yay :-) */
uint32_t nsegments = 0;
uint64_t free_sectors = 0, largest_segment = 0;
printf(_("No errors detected\n"));
printf(_("Header version: %s\n"), gpt_get_header_revstr(pheader));
printf(_("Using %d out of %d partitions\n"),
partitions_in_use(pheader, ents),
le32_to_cpu(pheader->npartition_entries));
free_sectors = get_free_sectors(cxt, pheader, ents,
&nsegments, &largest_segment);
printf(_("A total of %ld free sectors available in %d segment(s) "
"(largest %ld).\n"),
free_sectors, nsegments, largest_segment);
} else
printf(_("Detected %d error(s).\n"), nerror);
return 0;
}
/* Delete a single GPT partition, specified by partnum. */
static int gpt_delete_partition(struct fdisk_context *cxt, int partnum)
{
if (!cxt || partition_unused(ents[partnum]) || partnum < 0)
return -EINVAL;
/* hasta la vista, baby! */
memset(&ents[partnum], 0, sizeof(ents[partnum]));
if (!partition_unused(ents[partnum]))
return -EINVAL;
else {
gpt_recompute_crc(pheader, ents);
gpt_recompute_crc(bheader, ents);
}
return 0;
}
static void gpt_entry_set_type(struct gpt_entry *e, struct gpt_guid *type)
{
size_t i;
/*
* Copy corresponding partition type GUID. Only the first three blocks
* are endian-aware.
*/
e->partition_type_guid.time_low = cpu_to_le32(type->time_low);
e->partition_type_guid.time_mid = cpu_to_le16(type->time_mid);
e->partition_type_guid.time_hi_and_version = cpu_to_le16(type->time_hi_and_version);
e->partition_type_guid.clock_seq_hi = type->clock_seq_hi;
e->partition_type_guid.clock_seq_low = type->clock_seq_low;
for (i = 0; i < 6; i++)
e->partition_type_guid.node[i] = type->node[i];
DBG(LABEL, fprintf(stderr, "new type: %08X-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X\n",
type->time_low, type->time_mid, type->time_hi_and_version,
type->clock_seq_hi, type->clock_seq_low,
type->node[0], type->node[1], type->node[2],
type->node[3], type->node[4], type->node[5]));
}
/*
* Create a new GPT partition entry, specified by partnum, and with a range
* of fsect to lsenct sectors, of type t.
* Returns 0 on success, or negative upon failure.
*/
static int gpt_create_new_partition(int partnum, uint64_t fsect, uint64_t lsect,
struct gpt_guid *type,
struct gpt_entry *entries)
{
struct gpt_entry *e = NULL;
if (fsect > lsect || partnum < 0)
return -EINVAL;
e = xcalloc(1, sizeof(*e));
e->lba_end = cpu_to_le64(lsect);
e->lba_start = cpu_to_le64(fsect);
gpt_entry_set_type(e, type);
/* deal with partition name
for (i = 0; i < GPT_PART_NAME_LEN; i++)
e->partition_name[i] =
cpu_to_le16((uint16_t) gpt_sys_types[sys].name[i]);
*/
/*
* Any time a new partition entry is created a new GUID must be
* generated for that partition, and every partition is guaranteed
* to have a unique GUID.
*/
uuid_generate_random((unsigned char *) &e->unique_partition_guid);
swap_efi_guid(&e->unique_partition_guid);
memcpy(&entries[partnum] , e, sizeof(*e));
gpt_recompute_crc(pheader, entries);
gpt_recompute_crc(bheader, entries);
free(e);
return 0;
}
/* Performs logical checks to add a new partition entry */
static void gpt_add_partition(struct fdisk_context *cxt, int partnum,
struct fdisk_parttype *t)
{
char msg[256];
uint32_t tmp;
uint64_t f0, f1; /* user input ranges for first and last sectors */
uint64_t def_sect, first_sect, last_sect; /* first and last available sector ranges */
struct gpt_guid uuid = GPT_DEFAULT_ENTRY_GUID;
/* check basic tests before even considering adding a new partition */
if (!cxt || partnum < 0)
return;
if (!partition_unused(ents[partnum])) {
printf(_("Partition %d is already defined. "
"Delete it before re-adding it.\n"), partnum +1);
return;
}
if (le32_to_cpu(pheader->npartition_entries) == partitions_in_use(pheader, ents)) {
printf(_("All partitions are already in use.\n"));
return;
}
if (!get_free_sectors(cxt, pheader, ents, &tmp, &f0)) {
printf(_("No free sectors available.\n"));
return;
}
first_sect = find_first_available(pheader, ents, 0);
last_sect = find_last_free_sector(pheader, ents);
def_sect = find_first_in_largest(pheader, ents);
if (t && t->typestr)
string_to_uuid(t->typestr, &uuid);
/* get user input for first and last sectors of the new partition */
snprintf(msg, sizeof(msg), _("First %s"), str_units(SINGULAR));
for (;;) {
f0 = read_int(cxt, first_sect, def_sect, last_sect, 0, msg);
if (f0 >= first_sect && f0 <= last_sect) {
last_sect = find_last_free(pheader, ents, f0);
snprintf(msg, sizeof(msg), _("Last %s"), str_units(SINGULAR));
f1 = read_int(cxt, f0, last_sect, last_sect, 0, msg);
if (f1 >= f0 && f1 <= last_sect)
break;
}
}
if (gpt_create_new_partition(partnum, f0, f1, &uuid, ents) != 0)
printf(_("Could not create partition %d\n"), partnum + 1);
else
printf(_("Created partition %d\n"), partnum + 1);
}
static struct fdisk_parttype *gpt_get_partition_type(struct fdisk_context *cxt,
int i)
{
struct fdisk_parttype *t;
struct gpt_guid uuid;
char str[37];
if (!cxt || i < 0 || (uint32_t) i >= le32_to_cpu(pheader->npartition_entries))
return NULL;
uuid = ents[i].partition_type_guid;
swap_efi_guid(&uuid);
uuid_to_string(&uuid, str);
t = fdisk_get_parttype_from_string(cxt, str);
if (!t)
t = fdisk_new_unknown_parttype(0, str);
return t;
}
static int gpt_set_partition_type(struct fdisk_context *cxt, int i,
struct fdisk_parttype *t)
{
struct gpt_guid uuid;
if (!cxt || i < 0 || (uint32_t) i >= le32_to_cpu(pheader->npartition_entries) ||
!t || !t->typestr || string_to_uuid(t->typestr, &uuid) != 0)
return -EINVAL;
gpt_entry_set_type(&ents[i], &uuid);
gpt_recompute_crc(pheader, ents);
gpt_recompute_crc(bheader, ents);
return 0;
}
const struct fdisk_label gpt_label =
{
.name = "gpt",
.parttypes = gpt_parttypes,
.nparttypes = ARRAY_SIZE(gpt_parttypes),
.probe = gpt_probe_label,
.write = gpt_write_disklabel,
.verify = gpt_verify_disklabel,
.create = NULL,
.part_add = gpt_add_partition,
.part_delete = gpt_delete_partition,
.part_get_type = gpt_get_partition_type,
.part_set_type = gpt_set_partition_type
};
