radare2/shlr/grub/partmap/sunpc.c
2017-05-13 00:42:00 +02:00

140 lines
3.6 KiB
C

/* sunpc.c - Read SUN PC style partition tables. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2002,2005,2006,2007,2009 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/partition.h>
#include <grub/disk.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/dl.h>
#include <grub/symbol.h>
#include <grub/types.h>
#include <grub/err.h>
#include <r_types.h>
#define GRUB_PARTMAP_SUN_PC_MAGIC 0xDABE
#define GRUB_PARTMAP_SUN_PC_MAX_PARTS 16
#define GRUB_PARTMAP_SUN_PC_WHOLE_DISK_ID 0x05
R_PACKED (
struct grub_sun_pc_partition_descriptor
{
grub_uint16_t id;
grub_uint16_t unused;
grub_uint32_t start_sector;
grub_uint32_t num_sectors;
});
R_PACKED (
struct grub_sun_pc_block
{
grub_uint8_t unused[72];
struct grub_sun_pc_partition_descriptor partitions[GRUB_PARTMAP_SUN_PC_MAX_PARTS];
grub_uint8_t unused2[244];
grub_uint16_t magic; /* Magic number. */
grub_uint16_t csum; /* Label xor'd checksum. */
});
struct grub_partition_map grub_sun_pc_partition_map;
/* Verify checksum (true=ok). */
static int
grub_sun_is_valid (struct grub_sun_pc_block *label)
{
grub_uint16_t *pos;
grub_uint16_t sum = 0;
for (pos = (grub_uint16_t *) label;
pos < (grub_uint16_t *) (label + 1);
pos++)
sum ^= *pos;
return ! sum;
}
static grub_err_t
sun_pc_partition_map_iterate (grub_disk_t disk,
int (*hook) (grub_disk_t disk,
const grub_partition_t partition,
void *closure),
void *closure)
{
grub_partition_t p;
struct grub_sun_pc_block block;
int partnum;
grub_err_t err;
p = (grub_partition_t) grub_zalloc (sizeof (struct grub_partition));
if (! p)
return grub_errno;
p->partmap = &grub_sun_pc_partition_map;
err = grub_disk_read (disk, 1, 0, sizeof (struct grub_sun_pc_block), &block);
if (err)
{
grub_free (p);
return err;
}
if (GRUB_PARTMAP_SUN_PC_MAGIC != grub_le_to_cpu16 (block.magic))
{
grub_free (p);
return grub_error (GRUB_ERR_BAD_PART_TABLE,
"not a sun_pc partition table");
}
if (! grub_sun_is_valid (&block))
{
grub_free (p);
return grub_error (GRUB_ERR_BAD_PART_TABLE, "invalid checksum");
}
/* Maybe another error value would be better, because partition
table _is_ recognized but invalid. */
for (partnum = 0; partnum < GRUB_PARTMAP_SUN_PC_MAX_PARTS; partnum++)
{
struct grub_sun_pc_partition_descriptor *desc;
if (block.partitions[partnum].id == 0
|| block.partitions[partnum].id == GRUB_PARTMAP_SUN_PC_WHOLE_DISK_ID)
continue;
desc = &block.partitions[partnum];
p->start = grub_le_to_cpu32 (desc->start_sector);
p->len = grub_le_to_cpu32 (desc->num_sectors);
p->number = partnum;
if (p->len)
{
if (hook (disk, p, closure))
partnum = GRUB_PARTMAP_SUN_PC_MAX_PARTS;
}
}
grub_free (p);
return grub_errno;
}
/* Partition map type. */
struct grub_partition_map grub_sun_pc_partition_map =
{
.name = "sunpc",
.iterate = sun_pc_partition_map_iterate,
};