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/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/boot/common/disk.c 227705 2011-11-19 10:49:03Z pjd $");
/*
* MBR/GPT partitioned disk device handling.
*
* Ideas and algorithms from:
*
* - NetBSD libi386/biosdisk.c
* - FreeBSD biosboot/disk.c
*
*/
#include <stand.h>
#include <sys/diskmbr.h>
#include <sys/disklabel.h>
#include <sys/gpt.h>
#include <stdarg.h>
#include <uuid.h>
#include <bootstrap.h>
#include "disk.h"
#ifdef DISK_DEBUG
# define DEBUG(fmt, args...) printf("%s: " fmt "\n" , __func__ , ## args)
#else
# define DEBUG(fmt, args...)
#endif
/*
* Search for a slice with the following preferences:
*
* 1: Active FreeBSD slice
* 2: Non-active FreeBSD slice
* 3: Active Linux slice
* 4: non-active Linux slice
* 5: Active FAT/FAT32 slice
* 6: non-active FAT/FAT32 slice
*/
#define PREF_RAWDISK 0
#define PREF_FBSD_ACT 1
#define PREF_FBSD 2
#define PREF_LINUX_ACT 3
#define PREF_LINUX 4
#define PREF_DOS_ACT 5
#define PREF_DOS 6
#define PREF_NONE 7
#ifdef LOADER_GPT_SUPPORT
struct gpt_part {
int gp_index;
uuid_t gp_type;
uint64_t gp_start;
uint64_t gp_end;
};
static uuid_t efi = GPT_ENT_TYPE_EFI;
static uuid_t freebsd_boot = GPT_ENT_TYPE_FREEBSD_BOOT;
static uuid_t freebsd_ufs = GPT_ENT_TYPE_FREEBSD_UFS;
static uuid_t freebsd_swap = GPT_ENT_TYPE_FREEBSD_SWAP;
static uuid_t freebsd_zfs = GPT_ENT_TYPE_FREEBSD_ZFS;
static uuid_t ms_basic_data = GPT_ENT_TYPE_MS_BASIC_DATA;
#endif
#if defined(LOADER_GPT_SUPPORT) || defined(LOADER_MBR_SUPPORT)
/* Given a size in 512 byte sectors, convert it to a human-readable number. */
static char *
display_size(uint64_t size)
{
static char buf[80];
char unit;
size /= 2;
unit = 'K';
if (size >= 10485760000LL) {
size /= 1073741824;
unit = 'T';
} else if (size >= 10240000) {
size /= 1048576;
unit = 'G';
} else if (size >= 10000) {
size /= 1024;
unit = 'M';
}
sprintf(buf, "%.6ld%cB", (long)size, unit);
return (buf);
}
#endif
#ifdef LOADER_MBR_SUPPORT
static void
disk_checkextended(struct disk_devdesc *dev,
struct dos_partition *slicetab, int slicenum, int *nslicesp)
{
uint8_t buf[DISK_SECSIZE];
struct dos_partition *dp;
uint32_t base;
int rc, i, start, end;
dp = &slicetab[slicenum];
start = *nslicesp;
if (dp->dp_size == 0)
goto done;
if (dp->dp_typ != DOSPTYP_EXT)
goto done;
rc = dev->d_dev->dv_strategy(dev, F_READ, dp->dp_start, DISK_SECSIZE,
(char *) buf, NULL);
if (rc)
goto done;
if (buf[0x1fe] != 0x55 || buf[0x1ff] != 0xaa) {
DEBUG("no magic in extended table");
goto done;
}
base = dp->dp_start;
dp = (struct dos_partition *) &buf[DOSPARTOFF];
for (i = 0; i < NDOSPART; i++, dp++) {
if (dp->dp_size == 0)
continue;
if (*nslicesp == NEXTDOSPART)
goto done;
dp->dp_start += base;
bcopy(dp, &slicetab[*nslicesp], sizeof(*dp));
(*nslicesp)++;
}
end = *nslicesp;
/*
* now, recursively check the slices we just added
*/
for (i = start; i < end; i++)
disk_checkextended(dev, slicetab, i, nslicesp);
done:
return;
}
static int
disk_readslicetab(struct disk_devdesc *dev,
struct dos_partition **slicetabp, int *nslicesp)
{
struct dos_partition *slicetab = NULL;
int nslices, i;
int rc;
uint8_t buf[DISK_SECSIZE];
/*
* Find the slice in the DOS slice table.
*/
rc = dev->d_dev->dv_strategy(dev, F_READ, 0, DISK_SECSIZE,
(char *) buf, NULL);
if (rc) {
DEBUG("error reading MBR");
return (rc);
}
/*
* Check the slice table magic.
*/
if (buf[0x1fe] != 0x55 || buf[0x1ff] != 0xaa) {
DEBUG("no slice table/MBR (no magic)");
return (rc);
}
/*
* copy the partition table, then pick up any extended partitions.
*/
slicetab = malloc(NEXTDOSPART * sizeof(struct dos_partition));
bcopy(buf + DOSPARTOFF, slicetab,
sizeof(struct dos_partition) * NDOSPART);
nslices = NDOSPART; /* extended slices start here */
for (i = 0; i < NDOSPART; i++)
disk_checkextended(dev, slicetab, i, &nslices);
*slicetabp = slicetab;
*nslicesp = nslices;
return (0);
}
/*
* Search for the best MBR slice (typically the first FreeBSD slice).
*/
static int
disk_bestslice(struct dos_partition *slicetab, int nslices)
{
struct dos_partition *dp;
int pref, preflevel;
int i, prefslice;
prefslice = 0;
preflevel = PREF_NONE;
dp = &slicetab[0];
for (i = 0; i < nslices; i++, dp++) {
switch (dp->dp_typ) {
case DOSPTYP_386BSD: /* FreeBSD */
pref = dp->dp_flag & 0x80 ? PREF_FBSD_ACT : PREF_FBSD;
break;
case DOSPTYP_LINUX:
pref = dp->dp_flag & 0x80 ? PREF_LINUX_ACT : PREF_LINUX;
break;
case 0x01: /* DOS/Windows */
case 0x04:
case 0x06:
case 0x0b:
case 0x0c:
case 0x0e:
pref = dp->dp_flag & 0x80 ? PREF_DOS_ACT : PREF_DOS;
break;
default:
pref = PREF_NONE;
}
if (pref < preflevel) {
preflevel = pref;
prefslice = i + 1;
}
}
return (prefslice);
}
static int
disk_openmbr(struct disk_devdesc *dev)
{
struct dos_partition *slicetab = NULL, *dptr;
int nslices, sector, slice;
int rc;
uint8_t buf[DISK_SECSIZE];
struct disklabel *lp;
/*
* Following calculations attempt to determine the correct value
* for dev->d_offset by looking for the slice and partition specified,
* or searching for reasonable defaults.
*/
rc = disk_readslicetab(dev, &slicetab, &nslices);
if (rc)
return (rc);
/*
* if a slice number was supplied but not found, this is an error.
*/
if (dev->d_slice > 0) {
slice = dev->d_slice - 1;
if (slice >= nslices) {
DEBUG("slice %d not found", slice);
rc = EPART;
goto out;
}
}
/*
* Check for the historically bogus MBR found on true dedicated disks
*/
if (slicetab[3].dp_typ == DOSPTYP_386BSD &&
slicetab[3].dp_start == 0 && slicetab[3].dp_size == 50000) {
sector = 0;
goto unsliced;
}
/*
* Try to auto-detect the best slice; this should always give
* a slice number
*/
if (dev->d_slice == 0) {
slice = disk_bestslice(slicetab, nslices);
if (slice == -1) {
rc = ENOENT;
goto out;
}
dev->d_slice = slice;
}
/*
* Accept the supplied slice number unequivocally (we may be looking
* at a DOS partition).
* Note: we number 1-4, offsets are 0-3
*/
dptr = &slicetab[dev->d_slice - 1];
sector = dptr->dp_start;
DEBUG("slice entry %d at %d, %d sectors",
dev->d_slice - 1, sector, dptr->dp_size);
unsliced:
/*
* Now we have the slice offset, look for the partition in the
* disklabel if we have a partition to start with.
*
* XXX we might want to check the label checksum.
*/
if (dev->d_partition < 0) {
/* no partition, must be after the slice */
DEBUG("opening raw slice");
dev->d_offset = sector;
rc = 0;
goto out;
}
rc = dev->d_dev->dv_strategy(dev, F_READ, sector + LABELSECTOR,
DISK_SECSIZE, (char *) buf, NULL);
if (rc) {
DEBUG("error reading disklabel");
goto out;
}
lp = (struct disklabel *) buf;
if (lp->d_magic != DISKMAGIC) {
DEBUG("no disklabel");
rc = ENOENT;
goto out;
}
if (dev->d_partition >= lp->d_npartitions) {
DEBUG("partition '%c' exceeds partitions in table (a-'%c')",
'a' + dev->d_partition,
'a' + lp->d_npartitions);
rc = EPART;
goto out;
}
dev->d_offset =
lp->d_partitions[dev->d_partition].p_offset -
lp->d_partitions[RAW_PART].p_offset +
sector;
rc = 0;
out:
if (slicetab)
free(slicetab);
return (rc);
}
/*
* Print out each valid partition in the disklabel of a FreeBSD slice.
* For size calculations, we assume a 512 byte sector size.
*/
static void
disk_printbsdslice(struct disk_devdesc *dev, daddr_t offset,
char *prefix, int verbose)
{
char line[80];
char buf[DISK_SECSIZE];
struct disklabel *lp;
int i, rc, fstype;
/* read disklabel */
rc = dev->d_dev->dv_strategy(dev, F_READ, offset + LABELSECTOR,
DISK_SECSIZE, (char *) buf, NULL);
if (rc)
return;
lp =(struct disklabel *)(&buf[0]);
if (lp->d_magic != DISKMAGIC) {
sprintf(line, "%s: FFS bad disklabel\n", prefix);
pager_output(line);
return;
}
/* Print partitions */
for (i = 0; i < lp->d_npartitions; i++) {
/*
* For each partition, make sure we know what type of fs it
* is. If not, then skip it.
*/
fstype = lp->d_partitions[i].p_fstype;
if (fstype != FS_BSDFFS &&
fstype != FS_SWAP &&
fstype != FS_VINUM)
continue;
/* Only print out statistics in verbose mode */
if (verbose)
sprintf(line, " %s%c: %s %s (%d - %d)\n",
prefix, 'a' + i,
(fstype == FS_SWAP) ? "swap " :
(fstype == FS_VINUM) ? "vinum" :
"FFS ",
display_size(lp->d_partitions[i].p_size),
lp->d_partitions[i].p_offset,
(lp->d_partitions[i].p_offset
+ lp->d_partitions[i].p_size));
else
sprintf(line, " %s%c: %s\n", prefix, 'a' + i,
(fstype == FS_SWAP) ? "swap" :
(fstype == FS_VINUM) ? "vinum" :
"FFS");
pager_output(line);
}
}
static void
disk_printslice(struct disk_devdesc *dev, int slice,
struct dos_partition *dp, char *prefix, int verbose)
{
char stats[80];
char line[80];
if (verbose)
sprintf(stats, " %s (%d - %d)", display_size(dp->dp_size),
dp->dp_start, dp->dp_start + dp->dp_size);
else
stats[0] = '\0';
switch (dp->dp_typ) {
case DOSPTYP_386BSD:
disk_printbsdslice(dev, (daddr_t)dp->dp_start,
prefix, verbose);
return;
case DOSPTYP_LINSWP:
sprintf(line, "%s: Linux swap%s\n", prefix, stats);
break;
case DOSPTYP_LINUX:
/*
* XXX
* read the superblock to confirm this is an ext2fs partition?
*/
sprintf(line, "%s: ext2fs%s\n", prefix, stats);
break;
case 0x00: /* unused partition */
case DOSPTYP_EXT:
return;
case 0x01:
sprintf(line, "%s: FAT-12%s\n", prefix, stats);
break;
case 0x04:
case 0x06:
case 0x0e:
sprintf(line, "%s: FAT-16%s\n", prefix, stats);
break;
case 0x07:
sprintf(line, "%s: NTFS/HPFS%s\n", prefix, stats);
break;
case 0x0b:
case 0x0c:
sprintf(line, "%s: FAT-32%s\n", prefix, stats);
break;
default:
sprintf(line, "%s: Unknown fs: 0x%x %s\n", prefix, dp->dp_typ,
stats);
}
pager_output(line);
}
static int
disk_printmbr(struct disk_devdesc *dev, char *prefix, int verbose)
{
struct dos_partition *slicetab;
int nslices, i;
int rc;
char line[80];
rc = disk_readslicetab(dev, &slicetab, &nslices);
if (rc)
return (rc);
for (i = 0; i < nslices; i++) {
sprintf(line, "%ss%d", prefix, i + 1);
disk_printslice(dev, i, &slicetab[i], line, verbose);
}
free(slicetab);
return (0);
}
#endif
#ifdef LOADER_GPT_SUPPORT
static int
disk_readgpt(struct disk_devdesc *dev, struct gpt_part **gptp, int *ngptp)
{
struct dos_partition *dp;
struct gpt_hdr *hdr;
struct gpt_ent *ent;
struct gpt_part *gptab = NULL;
int entries_per_sec, rc, i, part;
daddr_t lba, elba;
uint8_t gpt[DISK_SECSIZE], tbl[DISK_SECSIZE];
/*
* Following calculations attempt to determine the correct value
* for dev->d_offset by looking for the slice and partition specified,
* or searching for reasonable defaults.
*/
rc = 0;
/* First, read the MBR and see if we have a PMBR. */
rc = dev->d_dev->dv_strategy(dev, F_READ, 0, DISK_SECSIZE,
(char *) tbl, NULL);
if (rc) {
DEBUG("error reading MBR");
return (EIO);
}
/* Check the slice table magic. */
if (tbl[0x1fe] != 0x55 || tbl[0x1ff] != 0xaa)
return (ENXIO);
/* Check for GPT slice. */
part = 0;
dp = (struct dos_partition *)(tbl + DOSPARTOFF);
for (i = 0; i < NDOSPART; i++) {
if (dp[i].dp_typ == 0xee)
part++;
else if ((part != 1) && (dp[i].dp_typ != 0x00))
return (EINVAL);
}
if (part != 1)
return (EINVAL);
/* Read primary GPT table header. */
rc = dev->d_dev->dv_strategy(dev, F_READ, 1, DISK_SECSIZE,
(char *) gpt, NULL);
if (rc) {
DEBUG("error reading GPT header");
return (EIO);
}
hdr = (struct gpt_hdr *)gpt;
if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
hdr->hdr_lba_self != 1 || hdr->hdr_revision < 0x00010000 ||
hdr->hdr_entsz < sizeof(*ent) ||
DISK_SECSIZE % hdr->hdr_entsz != 0) {
DEBUG("Invalid GPT header\n");
return (EINVAL);
}
/* Walk the partition table to count valid partitions. */
part = 0;
entries_per_sec = DISK_SECSIZE / hdr->hdr_entsz;
elba = hdr->hdr_lba_table + hdr->hdr_entries / entries_per_sec;
for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
rc = dev->d_dev->dv_strategy(dev, F_READ, lba, DISK_SECSIZE,
(char *) tbl, NULL);
if (rc) {
DEBUG("error reading GPT table");
return (EIO);
}
for (i = 0; i < entries_per_sec; i++) {
ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
if (uuid_is_nil(&ent->ent_type, NULL) ||
ent->ent_lba_start == 0 ||
ent->ent_lba_end < ent->ent_lba_start)
continue;
part++;
}
}
/* Save the important information about all the valid partitions. */
if (part != 0) {
gptab = malloc(part * sizeof(struct gpt_part));
part = 0;
for (lba = hdr->hdr_lba_table; lba < elba; lba++) {
rc = dev->d_dev->dv_strategy(dev, F_READ, lba, DISK_SECSIZE,
(char *) tbl, NULL);
if (rc) {
DEBUG("error reading GPT table");
free(gptab);
return (EIO);
}
for (i = 0; i < entries_per_sec; i++) {
ent = (struct gpt_ent *)(tbl + i * hdr->hdr_entsz);
if (uuid_is_nil(&ent->ent_type, NULL) ||
ent->ent_lba_start == 0 ||
ent->ent_lba_end < ent->ent_lba_start)
continue;
gptab[part].gp_index = (lba - hdr->hdr_lba_table) *
entries_per_sec + i + 1;
gptab[part].gp_type = ent->ent_type;
gptab[part].gp_start = ent->ent_lba_start;
gptab[part].gp_end = ent->ent_lba_end;
part++;
}
}
}
*gptp = gptab;
*ngptp = part;
return (0);
}
static struct gpt_part *
disk_bestgpt(struct gpt_part *gpt, int ngpt)
{
struct gpt_part *gp, *prefpart;
int i, pref, preflevel;
prefpart = NULL;
preflevel = PREF_NONE;
gp = gpt;
for (i = 0; i < ngpt; i++, gp++) {
/* Windows. XXX: Also Linux. */
if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
pref = PREF_DOS;
/* FreeBSD */
else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL) ||
uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
pref = PREF_FBSD;
else
pref = PREF_NONE;
if (pref < preflevel) {
preflevel = pref;
prefpart = gp;
}
}
return (prefpart);
}
static int
disk_opengpt(struct disk_devdesc *dev)
{
struct gpt_part *gpt = NULL, *gp;
int rc, ngpt, i;
rc = disk_readgpt(dev, &gpt, &ngpt);
if (rc)
return (rc);
/* Is this a request for the whole disk? */
if (dev->d_slice < 0) {
dev->d_offset = 0;
rc = 0;
goto out;
}
/*
* If a partition number was supplied, then the user is trying to use
* an MBR address rather than a GPT address, so fail.
*/
if (dev->d_partition != 0xff) {
rc = ENOENT;
goto out;
}
/* If a slice number was supplied but not found, this is an error. */
gp = NULL;
if (dev->d_slice > 0) {
for (i = 0; i < ngpt; i++) {
if (gpt[i].gp_index == dev->d_slice) {
gp = &gpt[i];
break;
}
}
if (gp == NULL) {
DEBUG("partition %d not found", dev->d_slice);
rc = ENOENT;
goto out;
}
}
/* Try to auto-detect the best partition. */
if (dev->d_slice == 0) {
gp = disk_bestgpt(gpt, ngpt);
if (gp == NULL) {
rc = ENOENT;
goto out;
}
dev->d_slice = gp->gp_index;
}
dev->d_offset = gp->gp_start;
rc = 0;
out:
if (gpt)
free(gpt);
return (rc);
}
static void
disk_printgptpart(struct disk_devdesc *dev, struct gpt_part *gp,
char *prefix, int verbose)
{
char stats[80];
char line[96];
if (verbose)
sprintf(stats, " %s",
display_size(gp->gp_end + 1 - gp->gp_start));
else
stats[0] = '\0';
if (uuid_equal(&gp->gp_type, &efi, NULL))
sprintf(line, "%s: EFI %s\n", prefix, stats);
else if (uuid_equal(&gp->gp_type, &ms_basic_data, NULL))
sprintf(line, "%s: FAT/NTFS %s\n", prefix, stats);
else if (uuid_equal(&gp->gp_type, &freebsd_boot, NULL))
sprintf(line, "%s: FreeBSD boot%s\n", prefix, stats);
else if (uuid_equal(&gp->gp_type, &freebsd_ufs, NULL))
sprintf(line, "%s: FreeBSD UFS %s\n", prefix, stats);
else if (uuid_equal(&gp->gp_type, &freebsd_zfs, NULL))
sprintf(line, "%s: FreeBSD ZFS %s\n", prefix, stats);
else if (uuid_equal(&gp->gp_type, &freebsd_swap, NULL))
sprintf(line, "%s: FreeBSD swap%s\n", prefix, stats);
else
sprintf(line,
"%s: %08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x%s\n",
prefix,
gp->gp_type.time_low, gp->gp_type.time_mid,
gp->gp_type.time_hi_and_version,
gp->gp_type.clock_seq_hi_and_reserved,
gp->gp_type.clock_seq_low,
gp->gp_type.node[0],
gp->gp_type.node[1],
gp->gp_type.node[2],
gp->gp_type.node[3],
gp->gp_type.node[4],
gp->gp_type.node[5],
stats);
pager_output(line);
}
static int
disk_printgpt(struct disk_devdesc *dev, char *prefix, int verbose)
{
struct gpt_part *gpt = NULL;
int rc, ngpt, i;
char line[80];
rc = disk_readgpt(dev, &gpt, &ngpt);
if (rc)
return (rc);
for (i = 0; i < ngpt; i++) {
sprintf(line, "%sp%d", prefix, i + 1);
disk_printgptpart(dev, &gpt[i], line, verbose);
}
free(gpt);
return (0);
}
#endif
int
disk_open(struct disk_devdesc *dev)
{
int rc;
rc = 0;
/*
* While we are reading disk metadata, make sure we do it relative
* to the start of the disk
*/
dev->d_offset = 0;
#ifdef LOADER_GPT_SUPPORT
rc = disk_opengpt(dev);
if (rc == 0)
return (0);
#endif
#ifdef LOADER_MBR_SUPPORT
rc = disk_openmbr(dev);
#endif
return (rc);
}
void
disk_print(struct disk_devdesc *dev, char *prefix, int verbose)
{
#ifdef LOADER_GPT_SUPPORT
if (disk_printgpt(dev, prefix, verbose) == 0)
return;
#endif
#ifdef LOADER_MBR_SUPPORT
disk_printmbr(dev, prefix, verbose);
#endif
}