/*
* mac partitions parsing code
*
* Copyright (C) 2009 Karel Zak <kzak@redhat.com>
*
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
*
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include "partitions.h"
#define MAC_PARTITION_MAGIC 0x504d
#define MAC_PARTITION_MAGIC_OLD 0x5453
/*
* Mac partition entry
* http://developer.apple.com/legacy/mac/library/documentation/mac/Devices/Devices-126.html
*/
struct mac_partition {
uint16_t signature; /* expected to be MAC_PARTITION_MAGIC */
uint16_t reserved; /* reserved */
uint32_t map_count; /* # blocks in partition map */
uint32_t start_block; /* absolute starting block # of partition */
uint32_t block_count; /* number of blocks in partition */
char name[32]; /* partition name */
char type[32]; /* string type description */
uint32_t data_start; /* rel block # of first data block */
uint32_t data_count; /* number of data blocks */
uint32_t status; /* partition status bits */
uint32_t boot_start; /* first logical block of boot code */
uint32_t boot_size; /* size of boot code, in bytes */
uint32_t boot_load; /* boot code load address */
uint32_t boot_load2; /* reserved */
uint32_t boot_entry; /* boot code entry point */
uint32_t boot_entry2; /* reserved */
uint32_t boot_cksum; /* boot code checksum */
char processor[16]; /* identifies ISA of boot */
/* there is more stuff after this that we don't need */
} __attribute__((packed));
/*
* Driver descriptor structure, in block 0
* http://developer.apple.com/legacy/mac/library/documentation/mac/Devices/Devices-121.html
*/
struct mac_driver_desc {
uint16_t signature; /* expected to be MAC_DRIVER_MAGIC */
uint16_t block_size; /* block size of the device */
uint32_t block_count; /* number of blocks on the device */
/* there is more stuff after this that we don't need */
} __attribute__((packed));
static inline unsigned char *get_mac_block(
blkid_probe pr,
uint16_t block_size,
uint32_t num)
{
return blkid_probe_get_buffer(pr,
(blkid_loff_t) num * block_size, block_size);
}
static inline int has_part_signature(struct mac_partition *p)
{
return be16_to_cpu(p->signature) == MAC_PARTITION_MAGIC ||
be16_to_cpu(p->signature) == MAC_PARTITION_MAGIC_OLD;
}
static int probe_mac_pt(blkid_probe pr,
const struct blkid_idmag *mag __attribute__((__unused__)))
{
struct mac_driver_desc *md;
struct mac_partition *p;
blkid_parttable tab = NULL;
blkid_partlist ls;
uint16_t block_size;
uint16_t ssf; /* sector size fragment */
uint32_t nblks, i;
/* The driver descriptor record is always located at physical block 0,
* the first block on the disk.
*/
md = (struct mac_driver_desc *) blkid_probe_get_sector(pr, 0);
if (!md)
goto nothing;
block_size = be16_to_cpu(md->block_size);
/* The partition map always begins at physical block 1,
* the second block on the disk.
*/
p = (struct mac_partition *) get_mac_block(pr, block_size, 1);
if (!p)
goto nothing;
/* check the first partition signature */
if (!has_part_signature(p))
goto nothing;
if (blkid_partitions_need_typeonly(pr))
/* caller does not ask for details about partitions */
return 0;
ls = blkid_probe_get_partlist(pr);
if (!ls)
goto err;
tab = blkid_partlist_new_parttable(ls, "mac", 0);
if (!tab)
goto err;
ssf = block_size / 512;
nblks = be32_to_cpu(p->map_count);
for (i = 1; i <= nblks; ++i) {
blkid_partition par;
uint32_t start;
uint32_t size;
p = (struct mac_partition *) get_mac_block(pr, block_size, i);
if (!p)
goto nothing;
if (!has_part_signature(p))
goto nothing;
if (be32_to_cpu(p->map_count) != nblks) {
DBG(DEBUG_LOWPROBE, printf(
"mac: inconsisten map_count in partition map, "
"entry[0]: %d, entry[%d]: %d\n",
nblks, i - 1,
be32_to_cpu(p->map_count)));
}
/*
* note that libparted ignores some mac partitions according to
* the partition name (e.g. "Apple_Free" or "Apple_Void"). We
* follows Linux kernel and all partitions are visible
*/
start = be32_to_cpu(p->start_block) * ssf;
size = be32_to_cpu(p->block_count) * ssf;
par = blkid_partlist_add_partition(ls, tab, start, size);
if (!par)
goto err;
blkid_partition_set_name(par, (unsigned char *) p->name,
sizeof(p->name));
blkid_partition_set_type_string(par, (unsigned char *) p->type,
sizeof(p->type));
}
return 0;
nothing:
return 1;
err:
return -1;
}
/*
* Mac disk always begin with "Driver Descriptor Record"
* (struct mac_driver_desc) and magic 0x4552.
*/
const struct blkid_idinfo mac_pt_idinfo =
{
.name = "mac",
.probefunc = probe_mac_pt,
.magics =
{
/* big-endian magic string */
{ .magic = "\x45\x52", .len = 2 },
{ NULL }
}
};
