static inline int is_empty_mbr(unsigned char *mbr)
{
struct dos_partition *p = mbr_get_partition(mbr, 0);
int i, nparts = 0;
for (i = 0; i < 4; i++) {
if (dos_partition_get_size(p) > 0)
nparts++;
p++;
}
return nparts == 0;
}
/*
* link partition from parent (DOS) to nested BSD partition table
*/
int fdisk_bsd_link_partition(struct fdisk_context *cxt)
{
size_t k, i;
int rc;
struct dos_partition *p;
struct bsd_disklabel *d = self_disklabel(cxt);
if (!cxt->parent || !fdisk_is_disklabel(cxt->parent, DOS)) {
fdisk_warnx(cxt, _("BSD label is not nested within a DOS partition."));
return -EINVAL;
}
/* ask for DOS partition */
rc = fdisk_ask_partnum(cxt->parent, &k, FALSE);
if (rc)
return rc;
/* ask for BSD partition */
rc = fdisk_ask_partnum(cxt, &i, TRUE);
if (rc)
return rc;
if (i >= BSD_MAXPARTITIONS)
return -EINVAL;
p = fdisk_dos_get_partition(cxt->parent, k);
d->d_partitions[i].p_size = dos_partition_get_size(p);
d->d_partitions[i].p_offset = dos_partition_get_start(p);
d->d_partitions[i].p_fstype = bsd_translate_fstype(p->sys_ind);
if (i >= d->d_npartitions)
d->d_npartitions = i + 1;
cxt->label->nparts_cur = d->d_npartitions;
fdisk_label_set_changed(cxt->label, 1);
fdisk_sinfo(cxt, FDISK_INFO_SUCCESS,
_("BSD partition '%c' linked to DOS partition %zu."),
'a' + (int) i, k + 1);
return 0;
}
static int bsd_initlabel (struct fdisk_context *cxt)
{
struct fdisk_bsd_label *l = self_label(cxt);
struct bsd_disklabel *d = self_disklabel(cxt);
struct bsd_partition *pp;
memset (d, 0, sizeof (struct bsd_disklabel));
d -> d_magic = BSD_DISKMAGIC;
if (strncmp (cxt->dev_path, "/dev/sd", 7) == 0)
d -> d_type = BSD_DTYPE_SCSI;
else
d -> d_type = BSD_DTYPE_ST506;
#if !defined (__alpha__)
d -> d_flags = BSD_D_DOSPART;
#else
d -> d_flags = 0;
#endif
d -> d_secsize = DEFAULT_SECTOR_SIZE; /* bytes/sector */
d -> d_nsectors = cxt->geom.sectors; /* sectors/track */
d -> d_ntracks = cxt->geom.heads; /* tracks/cylinder (heads) */
d -> d_ncylinders = cxt->geom.cylinders;
d -> d_secpercyl = cxt->geom.sectors * cxt->geom.heads;/* sectors/cylinder */
if (d -> d_secpercyl == 0)
d -> d_secpercyl = 1; /* avoid segfaults */
d -> d_secperunit = d -> d_secpercyl * d -> d_ncylinders;
d -> d_rpm = 3600;
d -> d_interleave = 1;
d -> d_trackskew = 0;
d -> d_cylskew = 0;
d -> d_headswitch = 0;
d -> d_trkseek = 0;
d -> d_magic2 = BSD_DISKMAGIC;
d -> d_bbsize = BSD_BBSIZE;
d -> d_sbsize = BSD_SBSIZE;
if (l->dos_part) {
d->d_npartitions = 4;
pp = &d->d_partitions[2]; /* Partition C should be the NetBSD partition */
pp->p_offset = dos_partition_get_start(l->dos_part);
pp->p_size = dos_partition_get_size(l->dos_part);
pp->p_fstype = BSD_FS_UNUSED;
pp = &d -> d_partitions[3]; /* Partition D should be the whole disk */
pp->p_offset = 0;
pp->p_size = d->d_secperunit;
pp->p_fstype = BSD_FS_UNUSED;
} else {
d->d_npartitions = 3;
pp = &d->d_partitions[2]; /* Partition C should be the whole disk */
pp->p_offset = 0;
pp->p_size = d->d_secperunit;
pp->p_fstype = BSD_FS_UNUSED;
}
return 0;
}
static int bsd_add_partition(struct fdisk_context *cxt,
struct fdisk_partition *pa)
{
struct fdisk_bsd_label *l = self_label(cxt);
struct bsd_disklabel *d = self_disklabel(cxt);
size_t i;
unsigned int begin = 0, end;
int rc = 0;
rc = fdisk_partition_next_partno(pa, cxt, &i);
if (rc)
return rc;
if (i >= BSD_MAXPARTITIONS)
return -ERANGE;
if (l->dos_part) {
begin = dos_partition_get_start(l->dos_part);
end = begin + dos_partition_get_size(l->dos_part) - 1;
} else
end = d->d_secperunit - 1;
/*
* First sector
*/
if (pa && pa->start_follow_default)
;
else if (pa && pa->start) {
if (pa->start < begin || pa->start > end)
return -ERANGE;
begin = pa->start;
} else {
struct fdisk_ask *ask = fdisk_new_ask();
if (!ask)
return -ENOMEM;
fdisk_ask_set_query(ask,
fdisk_context_use_cylinders(cxt) ?
_("First cylinder") : _("First sector"));
fdisk_ask_set_type(ask, FDISK_ASKTYPE_NUMBER);
fdisk_ask_number_set_low(ask, fdisk_cround(cxt, begin));
fdisk_ask_number_set_default(ask, fdisk_cround(cxt, begin));
fdisk_ask_number_set_high(ask, fdisk_cround(cxt, end));
rc = fdisk_do_ask(cxt, ask);
begin = fdisk_ask_number_get_result(ask);
fdisk_free_ask(ask);
if (rc)
return rc;
if (fdisk_context_use_cylinders(cxt))
begin = (begin - 1) * d->d_secpercyl;
}
/*
* Last sector
*/
if (pa && pa->end_follow_default)
;
else if (pa && pa->size) {
if (begin + pa->size > end)
return -ERANGE;
end = begin + pa->size;
} else {
/* ask user by dialog */
struct fdisk_ask *ask = fdisk_new_ask();
if (!ask)
return -ENOMEM;
fdisk_ask_set_type(ask, FDISK_ASKTYPE_OFFSET);
if (fdisk_context_use_cylinders(cxt)) {
fdisk_ask_set_query(ask, _("Last cylinder, +cylinders or +size{K,M,G,T,P}"));
fdisk_ask_number_set_unit(ask,
cxt->sector_size *
fdisk_context_get_units_per_sector(cxt));
} else {
fdisk_ask_set_query(ask, _("Last sector, +sectors or +size{K,M,G,T,P}"));
fdisk_ask_number_set_unit(ask,cxt->sector_size);
}
fdisk_ask_number_set_low(ask, fdisk_cround(cxt, begin));
fdisk_ask_number_set_default(ask, fdisk_cround(cxt, end));
fdisk_ask_number_set_high(ask, fdisk_cround(cxt, end));
fdisk_ask_number_set_base(ask, fdisk_cround(cxt, begin));
rc = fdisk_do_ask(cxt, ask);
end = fdisk_ask_number_get_result(ask);
fdisk_free_ask(ask);
if (rc)
return rc;
if (fdisk_context_use_cylinders(cxt))
end = end * d->d_secpercyl - 1;
}
d->d_partitions[i].p_size = end - begin + 1;
d->d_partitions[i].p_offset = begin;
d->d_partitions[i].p_fstype = BSD_FS_UNUSED;
if (i >= d->d_npartitions)
d->d_npartitions = i + 1;
cxt->label->nparts_cur = d->d_npartitions;
if (pa && pa->type)
bsd_set_parttype(cxt, i, pa->type);
fdisk_label_set_changed(cxt->label, 1);
return 0;
}
static int parse_dos_extended(blkid_probe pr, blkid_parttable tab,
uint32_t ex_start, uint32_t ex_size, int ssf)
{
blkid_partlist ls = blkid_probe_get_partlist(pr);
uint32_t cur_start = ex_start, cur_size = ex_size;
unsigned char *data;
int ct_nodata = 0; /* count ext.partitions without data partitions */
int i;
DBG(LOWPROBE, ul_debug("parse EBR [start=%d, size=%d]", ex_start/ssf, ex_size/ssf));
if (ex_start == 0) {
DBG(LOWPROBE, ul_debug("Bad offset in primary extended partition -- ignore"));
return 0;
}
while (1) {
struct dos_partition *p, *p0;
uint32_t start, size;
if (++ct_nodata > 100)
return BLKID_PROBE_OK;
data = blkid_probe_get_sector(pr, cur_start);
if (!data) {
if (errno)
return -errno;
goto leave; /* malformed partition? */
}
if (!mbr_is_valid_magic(data))
goto leave;
p0 = mbr_get_partition(data, 0);
/* Usually, the first entry is the real data partition,
* the 2nd entry is the next extended partition, or empty,
* and the 3rd and 4th entries are unused.
* However, DRDOS sometimes has the extended partition as
* the first entry (when the data partition is empty),
* and OS/2 seems to use all four entries.
* -- Linux kernel fs/partitions/dos.c
*
* See also http://en.wikipedia.org/wiki/Extended_boot_record
*/
/* Parse data partition */
for (p = p0, i = 0; i < 4; i++, p++) {
uint32_t abs_start;
blkid_partition par;
/* the start is relative to the parental ext.partition */
start = dos_partition_get_start(p) * ssf;
size = dos_partition_get_size(p) * ssf;
abs_start = cur_start + start; /* absolute start */
if (!size || is_extended(p))
continue;
if (i >= 2) {
/* extra checks to detect real data on
* 3rd and 4th entries */
if (start + size > cur_size)
continue;
if (abs_start < ex_start)
continue;
if (abs_start + size > ex_start + ex_size)
continue;
}
/* Avoid recursive non-empty links, see ct_nodata counter */
if (blkid_partlist_get_partition_by_start(ls, abs_start)) {
DBG(LOWPROBE, ul_debug("#%d: EBR duplicate data partition [abs start=%u] -- ignore",
i + 1, abs_start));
continue;
}
par = blkid_partlist_add_partition(ls, tab, abs_start, size);
if (!par)
return -ENOMEM;
blkid_partition_set_type(par, p->sys_ind);
blkid_partition_set_flags(par, p->boot_ind);
blkid_partition_gen_uuid(par);
ct_nodata = 0;
}
/* The first nested ext.partition should be a link to the next
* logical partition. Everything other (recursive ext.partitions)
* is junk.
*/
for (p = p0, i = 0; i < 4; i++, p++) {
start = dos_partition_get_start(p) * ssf;
size = dos_partition_get_size(p) * ssf;
if (size && is_extended(p)) {
if (start == 0)
DBG(LOWPROBE, ul_debug("#%d: EBR link offset is zero -- ignore", i + 1));
else
break;
}
}
if (i == 4)
goto leave;
cur_start = ex_start + start;
cur_size = size;
}
leave:
return BLKID_PROBE_OK;
}
static int fat_valid_superblock(blkid_probe pr,
const struct blkid_idmag *mag,
struct msdos_super_block *ms,
struct vfat_super_block *vs,
uint32_t *cluster_count, uint32_t *fat_size)
{
uint16_t sector_size, dir_entries, reserved;
uint32_t sect_count, __fat_size, dir_size, __cluster_count, fat_length;
uint32_t max_count;
/* extra check for FATs without magic strings */
if (mag->len <= 2) {
/* Old floppies have a valid MBR signature */
if (ms->ms_pmagic[0] != 0x55 || ms->ms_pmagic[1] != 0xAA)
return 0;
/*
* OS/2 and apparently DFSee will place a FAT12/16-like
* pseudo-superblock in the first 512 bytes of non-FAT
* filesystems --- at least JFS and HPFS, and possibly others.
* So we explicitly check for those filesystems at the
* FAT12/16 filesystem magic field identifier, and if they are
* present, we rule this out as a FAT filesystem, despite the
* FAT-like pseudo-header.
*/
if ((memcmp(ms->ms_magic, "JFS ", 8) == 0) ||
(memcmp(ms->ms_magic, "HPFS ", 8) == 0))
return 0;
}
/* fat counts(Linux kernel expects at least 1 FAT table) */
if (!ms->ms_fats)
return 0;
if (!ms->ms_reserved)
return 0;
if (!(0xf8 <= ms->ms_media || ms->ms_media == 0xf0))
return 0;
if (!is_power_of_2(ms->ms_cluster_size))
return 0;
sector_size = unaligned_le16(&ms->ms_sector_size);
if (!is_power_of_2(sector_size) ||
sector_size < 512 || sector_size > 4096)
return 0;
dir_entries = unaligned_le16(&ms->ms_dir_entries);
reserved = le16_to_cpu(ms->ms_reserved);
sect_count = unaligned_le16(&ms->ms_sectors);
if (sect_count == 0)
sect_count = le32_to_cpu(ms->ms_total_sect);
fat_length = le16_to_cpu(ms->ms_fat_length);
if (fat_length == 0)
fat_length = le32_to_cpu(vs->vs_fat32_length);
__fat_size = fat_length * ms->ms_fats;
dir_size = ((dir_entries * sizeof(struct vfat_dir_entry)) +
(sector_size-1)) / sector_size;
__cluster_count = (sect_count - (reserved + __fat_size + dir_size)) /
ms->ms_cluster_size;
if (!ms->ms_fat_length && vs->vs_fat32_length)
max_count = FAT32_MAX;
else
max_count = __cluster_count > FAT12_MAX ? FAT16_MAX : FAT12_MAX;
if (__cluster_count > max_count)
return 0;
if (fat_size)
*fat_size = __fat_size;
if (cluster_count)
*cluster_count = __cluster_count;
#if 0
if (blkid_probe_is_wholedisk(pr)) {
/* OK, seems like FAT, but it's possible that we found boot
* sector with crazy FAT-like stuff (magic strings, media,
* etc..) before MBR. Let's make sure that there is no MBR with
* usable partition. */
unsigned char *buf = (unsigned char *) ms;
if (mbr_is_valid_magic(buf)) {
struct dos_partition *p0 = mbr_get_partition(buf, 0);
if (dos_partition_get_size(p0) != 0 &&
(p0->boot_ind == 0 || p0->boot_ind == 0x80))
return 0;
}
}
#endif
return 1; /* valid */
}
