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 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;
while (1) {
struct dos_partition *p, *p0;
uint32_t start, size;
if (++ct_nodata > 100)
return 0;
data = blkid_probe_get_sector(pr, cur_start);
if (!data)
goto leave; /* malformed partition? */
if (!is_valid_mbr_signature(data))
goto leave;
p0 = (struct dos_partition *) (data + BLKID_MSDOS_PT_OFFSET);
/* 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_start(p) * ssf;
size = dos_partition_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;
}
par = blkid_partlist_add_partition(ls, tab, abs_start, size);
if (!par)
goto err;
blkid_partition_set_type(par, p->sys_type);
blkid_partition_set_flags(par, p->boot_ind);
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_start(p) * ssf;
size = dos_partition_size(p) * ssf;
if (size && is_extended(p))
break;
}
if (i == 4)
goto leave;
cur_start = ex_start + start;
cur_size = size;
}
leave:
return 0;
err:
return -1;
}
static int probe_bsd_pt(blkid_probe pr, const struct blkid_idmag *mag)
{
struct bsd_disklabel *l;
struct bsd_partition *p;
const char *name = "bsd" ;
blkid_parttable tab = NULL;
blkid_partition parent;
blkid_partlist ls;
int i, nparts = BSD_MAXPARTITIONS;
unsigned char *data;
int rc = BLKID_PROBE_NONE;
if (blkid_partitions_need_typeonly(pr))
/* caller does not ask for details about partitions */
return rc;
data = blkid_probe_get_sector(pr, BLKID_MAG_SECTOR(mag));
if (!data) {
if (errno)
rc = -errno;
goto nothing;
}
l = (struct bsd_disklabel *) data + BLKID_MAG_LASTOFFSET(mag);
ls = blkid_probe_get_partlist(pr);
if (!ls)
goto nothing;
/* try to determine the real type of BSD system according to
* (parental) primary partition */
parent = blkid_partlist_get_parent(ls);
if (parent) {
switch(blkid_partition_get_type(parent)) {
case MBR_FREEBSD_PARTITION:
name = "freebsd";
break;
case MBR_NETBSD_PARTITION:
name = "netbsd";
break;
case MBR_OPENBSD_PARTITION:
name = "openbsd";
break;
default:
DBG(LOWPROBE, ul_debug(
"WARNING: BSD label detected on unknown (0x%x) "
"primary partition",
blkid_partition_get_type(parent)));
break;
}
}
tab = blkid_partlist_new_parttable(ls, name, BLKID_MAG_OFFSET(mag));
if (!tab) {
rc = -ENOMEM;
goto nothing;
}
if (le16_to_cpu(l->d_npartitions) < BSD_MAXPARTITIONS)
nparts = le16_to_cpu(l->d_npartitions);
else if (le16_to_cpu(l->d_npartitions) > BSD_MAXPARTITIONS)
DBG(LOWPROBE, ul_debug(
"WARNING: ignore %d more BSD partitions",
le16_to_cpu(l->d_npartitions) - BSD_MAXPARTITIONS));
for (i = 0, p = l->d_partitions; i < nparts; i++, p++) {
blkid_partition par;
uint32_t start, size;
/* TODO: in fdisk-mode returns all non-zero (p_size) partitions */
if (p->p_fstype == BSD_FS_UNUSED)
continue;
start = le32_to_cpu(p->p_offset);
size = le32_to_cpu(p->p_size);
if (parent && blkid_partition_get_start(parent) == start
&& blkid_partition_get_size(parent) == size) {
DBG(LOWPROBE, ul_debug(
"WARNING: BSD partition (%d) same like parent, "
"ignore", i));
continue;
}
if (parent && !blkid_is_nested_dimension(parent, start, size)) {
DBG(LOWPROBE, ul_debug(
"WARNING: BSD partition (%d) overflow "
"detected, ignore", i));
continue;
}
par = blkid_partlist_add_partition(ls, tab, start, size);
if (!par) {
rc = -ENOMEM;
goto nothing;
}
blkid_partition_set_type(par, p->p_fstype);
}
return BLKID_PROBE_OK;
nothing:
return rc;
}
