/**
* parse_vblk - parse a LDM database vblk record
* @buffer: vblk record loaded from the LDM database
* @buf_size: size of @buffer in bytes
* @vb: in memory vblk structure to return parsed information in
*
* This parses the LDM database vblk record supplied in @buffer and sets up
* the in memory vblk structure @vb with the obtained information.
*
* Return 1 on success, 0 if successful but record not in use, and -1 on error.
* If the return value is 0 or -1, @vb is undefined.
*
* NOTE: Currently the only record type we handle is VBLK_PART, i.e. records
* describing a partition. For all others, we just set @vb->vblk_type to 0 and
* return success. This of course means that if @vb->vblk_type is zero, all
* other fields in @vb are undefined.
*/
static int parse_vblk(const u8 *buffer, const int buf_size, struct vblk *vb)
{
int err = 1;
if (buf_size < 0x14)
return -1;
if (MAGIC_VBLK != BE32(buffer)) {
printk(LDM_CRIT "Cannot find VBLK, database may be corrupt.\n");
return -1;
}
if ((BE16(buffer + 0x0E) == 0) || /* Record is not in use. */
(BE16(buffer + 0x0C) != 0)) /* Part 2 of an ext. record */
return 0;
/* FIXME: What about extended VBLKs? */
switch (buffer[0x13]) {
case VBLK_PART:
err = parse_vblk_part(buffer, buf_size, vb);
break;
default:
vb->vblk_type = 0;
}
if (err != -1)
ldm_debug("Parsed VBLK successfully.\n");
return err;
}
/**
* ldm_parse_vmdb - Read the LDM Database VMDB structure
* @data: Raw database VMDB structure loaded from the device
* @vm: In-memory vmdb structure in which to return parsed information
*
* This parses the LDM Database VMDB structure supplied in @data and sets up
* the in-memory vmdb structure @vm with the obtained information.
*
* N.B. The *_start, *_size and *_seq values will be range-checked later.
*
* Return: 'true' @vm contains VMDB info
* 'false' @vm contents are undefined
*/
static bool ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
{
BUG_ON (!data || !vm);
if (MAGIC_VMDB != get_unaligned_be32(data)) {
ldm_crit ("Cannot find the VMDB, database may be corrupt.");
return false;
}
vm->ver_major = get_unaligned_be16(data + 0x12);
vm->ver_minor = get_unaligned_be16(data + 0x14);
if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {
ldm_error ("Expected VMDB version %d.%d, got %d.%d. "
"Aborting.", 4, 10, vm->ver_major, vm->ver_minor);
return false;
}
vm->vblk_size = get_unaligned_be32(data + 0x08);
if (vm->vblk_size == 0) {
ldm_error ("Illegal VBLK size");
return false;
}
vm->vblk_offset = get_unaligned_be32(data + 0x0C);
vm->last_vblk_seq = get_unaligned_be32(data + 0x04);
ldm_debug ("Parsed VMDB successfully.");
return true;
}
/**
* ldm_parse_tocblock - Read the LDM Database TOCBLOCK structure
* @data: Raw database TOCBLOCK structure loaded from the device
* @toc: In-memory toc structure in which to return parsed information
*
* This parses the LDM Database TOCBLOCK (table of contents) structure supplied
* in @data and sets up the in-memory tocblock structure @toc with the obtained
* information.
*
* N.B. The *_start and *_size values returned in @toc are not range-checked.
*
* Return: 'true' @toc contains the TOCBLOCK data
* 'false' @toc contents are undefined
*/
static bool ldm_parse_tocblock (const u8 *data, struct tocblock *toc)
{
BUG_ON (!data || !toc);
if (MAGIC_TOCBLOCK != get_unaligned_be64(data)) {
ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
return false;
}
strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
toc->bitmap1_start = get_unaligned_be64(data + 0x2E);
toc->bitmap1_size = get_unaligned_be64(data + 0x36);
if (strncmp (toc->bitmap1_name, TOC_BITMAP1,
sizeof (toc->bitmap1_name)) != 0) {
ldm_crit ("TOCBLOCK's first bitmap is '%s', should be '%s'.",
TOC_BITMAP1, toc->bitmap1_name);
return false;
}
strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
toc->bitmap2_start = get_unaligned_be64(data + 0x50);
toc->bitmap2_size = get_unaligned_be64(data + 0x58);
if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
sizeof (toc->bitmap2_name)) != 0) {
ldm_crit ("TOCBLOCK's second bitmap is '%s', should be '%s'.",
TOC_BITMAP2, toc->bitmap2_name);
return false;
}
ldm_debug ("Parsed TOCBLOCK successfully.");
return true;
}
/**
* ldm_parse_privhead - Read the LDM Database PRIVHEAD structure
* @data: Raw database PRIVHEAD structure loaded from the device
* @ph: In-memory privhead structure in which to return parsed information
*
* This parses the LDM database PRIVHEAD structure supplied in @data and
* sets up the in-memory privhead structure @ph with the obtained information.
*
* Return: 'true' @ph contains the PRIVHEAD data
* 'false' @ph contents are undefined
*/
static bool ldm_parse_privhead(const u8 *data, struct privhead *ph)
{
bool is_vista = false;
BUG_ON(!data || !ph);
if (MAGIC_PRIVHEAD != get_unaligned_be64(data)) {
ldm_error("Cannot find PRIVHEAD structure. LDM database is"
" corrupt. Aborting.");
return false;
}
ph->ver_major = get_unaligned_be16(data + 0x000C);
ph->ver_minor = get_unaligned_be16(data + 0x000E);
ph->logical_disk_start = get_unaligned_be64(data + 0x011B);
ph->logical_disk_size = get_unaligned_be64(data + 0x0123);
ph->config_start = get_unaligned_be64(data + 0x012B);
ph->config_size = get_unaligned_be64(data + 0x0133);
/* Version 2.11 is Win2k/XP and version 2.12 is Vista. */
if (ph->ver_major == 2 && ph->ver_minor == 12)
is_vista = true;
if (!is_vista && (ph->ver_major != 2 || ph->ver_minor != 11)) {
ldm_error("Expected PRIVHEAD version 2.11 or 2.12, got %d.%d."
" Aborting.", ph->ver_major, ph->ver_minor);
return false;
}
ldm_debug("PRIVHEAD version %d.%d (Windows %s).", ph->ver_major,
ph->ver_minor, is_vista ? "Vista" : "2000/XP");
if (ph->config_size != LDM_DB_SIZE) { /* 1 MiB in sectors. */
/* Warn the user and continue, carefully. */
ldm_info("Database is normally %u bytes, it claims to "
"be %llu bytes.", LDM_DB_SIZE,
(unsigned long long)ph->config_size);
}
if ((ph->logical_disk_size == 0) || (ph->logical_disk_start +
ph->logical_disk_size > ph->config_start)) {
ldm_error("PRIVHEAD disk size doesn't match real disk size");
return false;
}
if (!ldm_parse_guid(data + 0x0030, ph->disk_id)) {
ldm_error("PRIVHEAD contains an invalid GUID.");
return false;
}
ldm_debug("Parsed PRIVHEAD successfully.");
return true;
}
/**
* parse_vblk_part - parse a LDM database vblk partition record
* @buffer: vblk partition record loaded from the LDM database
* @buf_size: size of @buffer in bytes
* @vb: in memory vblk structure to return parsed information in
*
* This parses the LDM database vblk record of type VBLK_PART, i.e. a partition
* record, supplied in @buffer and sets up the in memory vblk structure @vb
* with the obtained information.
*
* Return 1 on success and -1 on error, in which case @vb is undefined.
*/
static int parse_vblk_part(const u8 *buffer, const int buf_size,
struct vblk *vb)
{
int err, rel_objid, rel_name, rel_size, rel_parent;
if (0x34 >= buf_size)
return -1;
/* Calculate relative offsets. */
rel_objid = 1 + buffer[0x18];
if (0x18 + rel_objid >= buf_size)
return -1;
rel_name = 1 + buffer[0x18 + rel_objid] + rel_objid;
if (0x34 + rel_name >= buf_size)
return -1;
rel_size = 1 + buffer[0x34 + rel_name] + rel_name;
if (0x34 + rel_size >= buf_size)
return -1;
rel_parent = 1 + buffer[0x34 + rel_size] + rel_size;
if (0x34 + rel_parent >= buf_size)
return -1;
/* Setup @vb. */
vb->vblk_type = VBLK_PART;
vb->obj_id = get_vnum(buffer + 0x18, &err);
if (err || 0x34 + rel_parent + buffer[0x34 + rel_parent] >= buf_size)
return -1;
vb->disk_id = get_vnum(buffer + 0x34 + rel_parent, &err);
if (err || 0x24 + rel_name + 8 > buf_size)
return -1;
vb->start_sector = BE64(buffer + 0x24 + rel_name);
if (0x34 + rel_name + buffer[0x34 + rel_name] >= buf_size)
return -1;
vb->num_sectors = get_vnum(buffer + 0x34 + rel_name, &err);
if (err || 0x18 + rel_objid + buffer[0x18 + rel_objid] >= buf_size)
return -1;
err = get_vstr(buffer + 0x18 + rel_objid, vb->name, sizeof(vb->name));
if (err == -1)
return err;
ldm_debug("Parsed Partition VBLK successfully.\n");
return 1;
}
/**
* ldm_validate_tocblocks - Validate the table of contents and its backups
* @state: Partition check state including device holding the LDM Database
* @base: Offset, into @state->bdev, of the database
* @ldb: Cache of the database structures
*
* Find and compare the four tables of contents of the LDM Database stored on
* @state->bdev and return the parsed information into @toc1.
*
* The offsets and sizes of the configs are range-checked against a privhead.
*
* Return: 'true' @toc1 contains validated TOCBLOCK info
* 'false' @toc1 contents are undefined
*/
static bool ldm_validate_tocblocks(struct parsed_partitions *state,
unsigned long base, struct ldmdb *ldb)
{
static const int off[4] = { OFF_TOCB1, OFF_TOCB2, OFF_TOCB3, OFF_TOCB4};
struct tocblock *tb[4];
struct privhead *ph;
Sector sect;
u8 *data;
int i, nr_tbs;
bool result = false;
BUG_ON(!state || !ldb);
ph = &ldb->ph;
tb[0] = &ldb->toc;
tb[1] = kmalloc(sizeof(*tb[1]) * 3, GFP_KERNEL);
if (!tb[1]) {
ldm_crit("Out of memory.");
goto err;
}
tb[2] = (struct tocblock*)((u8*)tb[1] + sizeof(*tb[1]));
tb[3] = (struct tocblock*)((u8*)tb[2] + sizeof(*tb[2]));
/*
* Try to read and parse all four TOCBLOCKs.
*
* Windows Vista LDM v2.12 does not always have all four TOCBLOCKs so
* skip any that fail as long as we get at least one valid TOCBLOCK.
*/
for (nr_tbs = i = 0; i < 4; i++) {
data = read_part_sector(state, base + off[i], §);
if (!data) {
ldm_error("Disk read failed for TOCBLOCK %d.", i);
continue;
}
if (ldm_parse_tocblock(data, tb[nr_tbs]))
nr_tbs++;
put_dev_sector(sect);
}
if (!nr_tbs) {
ldm_crit("Failed to find a valid TOCBLOCK.");
goto err;
}
/* Range check the TOCBLOCK against a privhead. */
if (((tb[0]->bitmap1_start + tb[0]->bitmap1_size) > ph->config_size) ||
((tb[0]->bitmap2_start + tb[0]->bitmap2_size) >
ph->config_size)) {
ldm_crit("The bitmaps are out of range. Giving up.");
goto err;
}
/* Compare all loaded TOCBLOCKs. */
for (i = 1; i < nr_tbs; i++) {
if (!ldm_compare_tocblocks(tb[0], tb[i])) {
ldm_crit("TOCBLOCKs 0 and %d do not match.", i);
goto err;
}
}
ldm_debug("Validated %d TOCBLOCKs successfully.", nr_tbs);
result = true;
err:
kfree(tb[1]);
return result;
}
/**
* ldm_validate_privheads - Compare the primary privhead with its backups
* @state: Partition check state including device holding the LDM Database
* @ph1: Memory struct to fill with ph contents
*
* Read and compare all three privheads from disk.
*
* The privheads on disk show the size and location of the main disk area and
* the configuration area (the database). The values are range-checked against
* @hd, which contains the real size of the disk.
*
* Return: 'true' Success
* 'false' Error
*/
static bool ldm_validate_privheads(struct parsed_partitions *state,
struct privhead *ph1)
{
static const int off[3] = { OFF_PRIV1, OFF_PRIV2, OFF_PRIV3 };
struct privhead *ph[3] = { ph1 };
Sector sect;
u8 *data;
bool result = false;
long num_sects;
int i;
BUG_ON (!state || !ph1);
ph[1] = kmalloc (sizeof (*ph[1]), GFP_KERNEL);
ph[2] = kmalloc (sizeof (*ph[2]), GFP_KERNEL);
if (!ph[1] || !ph[2]) {
ldm_crit ("Out of memory.");
goto out;
}
/* off[1 & 2] are relative to ph[0]->config_start */
ph[0]->config_start = 0;
/* Read and parse privheads */
for (i = 0; i < 3; i++) {
data = read_part_sector(state, ph[0]->config_start + off[i],
§);
if (!data) {
ldm_crit ("Disk read failed.");
goto out;
}
result = ldm_parse_privhead (data, ph[i]);
put_dev_sector (sect);
if (!result) {
ldm_error ("Cannot find PRIVHEAD %d.", i+1); /* Log again */
if (i < 2)
goto out; /* Already logged */
else
break; /* FIXME ignore for now, 3rd PH can fail on odd-sized disks */
}
}
num_sects = state->bdev->bd_inode->i_size >> 9;
if ((ph[0]->config_start > num_sects) ||
((ph[0]->config_start + ph[0]->config_size) > num_sects)) {
ldm_crit ("Database extends beyond the end of the disk.");
goto out;
}
if ((ph[0]->logical_disk_start > ph[0]->config_start) ||
((ph[0]->logical_disk_start + ph[0]->logical_disk_size)
> ph[0]->config_start)) {
ldm_crit ("Disk and database overlap.");
goto out;
}
if (!ldm_compare_privheads (ph[0], ph[1])) {
ldm_crit ("Primary and backup PRIVHEADs don't match.");
goto out;
}
/* FIXME ignore this for now
if (!ldm_compare_privheads (ph[0], ph[2])) {
ldm_crit ("Primary and backup PRIVHEADs don't match.");
goto out;
}*/
ldm_debug ("Validated PRIVHEADs successfully.");
result = true;
out:
kfree (ph[1]);
kfree (ph[2]);
return result;
}
