summaryrefslogtreecommitdiffstats
path: root/libblkid/dos.c
diff options
context:
space:
mode:
Diffstat (limited to 'libblkid/dos.c')
-rw-r--r--libblkid/dos.c297
1 files changed, 0 insertions, 297 deletions
diff --git a/libblkid/dos.c b/libblkid/dos.c
deleted file mode 100644
index 58877691d..000000000
--- a/libblkid/dos.c
+++ /dev/null
@@ -1,297 +0,0 @@
-/*
- * MS-DOS partition 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.
- *
- * Inspired by fdisk, partx, Linux kernel and libparted.
- */
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <stdint.h>
-
-#include "partitions.h"
-#include "dos.h"
-#include "aix.h"
-
-/* see superblocks/vfat.c */
-extern int blkid_probe_is_vfat(blkid_probe pr);
-
-static const struct dos_subtypes {
- unsigned char type;
- const struct blkid_idinfo *id;
-} dos_nested[] = {
- { BLKID_FREEBSD_PARTITION, &bsd_pt_idinfo },
- { BLKID_NETBSD_PARTITION, &bsd_pt_idinfo },
- { BLKID_OPENBSD_PARTITION, &bsd_pt_idinfo },
- { BLKID_UNIXWARE_PARTITION, &unixware_pt_idinfo },
- { BLKID_SOLARIS_X86_PARTITION, &solaris_x86_pt_idinfo },
- { BLKID_MINIX_PARTITION, &minix_pt_idinfo }
-};
-
-static inline int is_extended(struct dos_partition *p)
-{
- return (p->sys_type == BLKID_DOS_EXTENDED_PARTITION ||
- p->sys_type == BLKID_W95_EXTENDED_PARTITION ||
- p->sys_type == BLKID_LINUX_EXTENDED_PARTITION);
-}
-
-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_dos_pt(blkid_probe pr,
- const struct blkid_idmag *mag __attribute__((__unused__)))
-{
- int i;
- int ssf;
- blkid_parttable tab = NULL;
- blkid_partlist ls;
- struct dos_partition *p0, *p;
- unsigned char *data;
- uint32_t start, size, id;
-
- data = blkid_probe_get_sector(pr, 0);
- if (!data)
- goto nothing;
-
- /* ignore disks with AIX magic number -- for more details see aix.c */
- if (memcmp(data, BLKID_AIX_MAGIC_STRING, BLKID_AIX_MAGIC_STRLEN) == 0)
- goto nothing;
-
- /*
- * Now that the 55aa signature is present, this is probably
- * either the boot sector of a FAT filesystem or a DOS-type
- * partition table.
- */
- if (blkid_probe_is_vfat(pr)) {
- DBG(DEBUG_LOWPROBE, printf("probably FAT -- ignore\n"));
- goto nothing;
- }
-
- p0 = (struct dos_partition *) (data + BLKID_MSDOS_PT_OFFSET);
-
- /*
- * Reject PT where boot indicator is not 0 or 0x80.
- */
- for (p = p0, i = 0; i < 4; i++, p++)
- if (p->boot_ind != 0 && p->boot_ind != 0x80) {
- DBG(DEBUG_LOWPROBE, printf("missing boot indicator -- ignore\n"));
- goto nothing;
- }
-
- /*
- * GPT uses valid MBR
- */
- for (p = p0, i = 0; i < 4; i++, p++) {
- if (p->sys_type == BLKID_GPT_PARTITION) {
- DBG(DEBUG_LOWPROBE, printf("probably GPT -- ignore\n"));
- goto nothing;
- }
- }
-
- blkid_probe_use_wiper(pr, BLKID_MSDOS_PT_OFFSET,
- 512 - BLKID_MSDOS_PT_OFFSET);
-
- /*
- * Well, all checks pass, it's MS-DOS partiton table
- */
- if (blkid_partitions_need_typeonly(pr))
- /* caller does not ask for details about partitions */
- return 0;
-
- ls = blkid_probe_get_partlist(pr);
-
- /* sector size factor (the start and size are in the real sectors, but
- * we need to convert all sizes to 512 logical sectors
- */
- ssf = blkid_probe_get_sectorsize(pr) / 512;
-
- /* allocate a new partition table */
- tab = blkid_partlist_new_parttable(ls, "dos", BLKID_MSDOS_PT_OFFSET);
- if (!tab)
- goto err;
-
- id = dos_parttable_id(data);
- if (id) {
- char buf[37];
-
- snprintf(buf, sizeof(buf), "0x%08x", id);
- blkid_parttable_set_id(tab, (unsigned char *) buf);
- }
-
-
- /* Parse primary partitions */
- for (p = p0, i = 0; i < 4; i++, p++) {
- blkid_partition par;
-
- start = dos_partition_start(p) * ssf;
- size = dos_partition_size(p) * ssf;
-
- if (!size) {
- /* Linux kernel ignores empty partitions, but partno for
- * the empty primary partitions is not reused */
- blkid_partlist_increment_partno(ls);
- continue;
- }
- par = blkid_partlist_add_partition(ls, tab, start, size);
- if (!par)
- goto err;
-
- blkid_partition_set_type(par, p->sys_type);
- blkid_partition_set_flags(par, p->boot_ind);
- }
-
- /* Linux uses partition numbers greater than 4
- * for all logical partition and all nested partition tables (bsd, ..)
- */
- blkid_partlist_set_partno(ls, 5);
-
- /* Parse logical partitions */
- for (p = p0, i = 0; i < 4; i++, p++) {
- start = dos_partition_start(p) * ssf;
- size = dos_partition_size(p) * ssf;
-
- if (!size)
- continue;
- if (is_extended(p) &&
- parse_dos_extended(pr, tab, start, size, ssf) == -1)
- goto err;
- }
-
- /* Parse subtypes (nested partitions) on large disks */
- if (!blkid_probe_is_tiny(pr)) {
- for (p = p0, i = 0; i < 4; i++, p++) {
- size_t n;
-
- if (!dos_partition_size(p) || is_extended(p))
- continue;
-
- for (n = 0; n < ARRAY_SIZE(dos_nested); n++) {
- if (dos_nested[n].type != p->sys_type)
- continue;
-
- if (blkid_partitions_do_subprobe(pr,
- blkid_partlist_get_partition(ls, i),
- dos_nested[n].id) == -1)
- goto err;
- break;
- }
- }
- }
- return 0;
-
-nothing:
- return 1;
-err:
- return -1;
-}
-
-
-const struct blkid_idinfo dos_pt_idinfo =
-{
- .name = "dos",
- .probefunc = probe_dos_pt,
- .magics =
- {
- /* DOS master boot sector:
- *
- * 0 | Code Area
- * 440 | Optional Disk signature
- * 446 | Partition table
- * 510 | 0x55
- * 511 | 0xAA
- */
- { .magic = "\x55\xAA", .len = 2, .sboff = 510 },
- { NULL }
- }
-};
-
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-03 15:49:38 +0200