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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/block/partitions/ldm.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/**
* ldm - Support for Windows Logical Disk Manager (Dynamic Disks)
*
* Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
* Copyright (c) 2001-2012 Anton Altaparmakov
* Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
*
* Documentation is available at http://www.linux-ntfs.org/doku.php?id=downloads
*/
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/stringify.h>
#include <linux/kernel.h>
#include <linux/uuid.h>
#include <linux/msdos_partition.h>
#include "ldm.h"
#include "check.h"
/*
* ldm_debug/info/error/crit - Output an error message
* @f: A printf format string containing the message
* @...: Variables to substitute into @f
*
* ldm_debug() writes a DEBUG level message to the syslog but only if the
* driver was compiled with debug enabled. Otherwise, the call turns into a NOP.
*/
#ifndef CONFIG_LDM_DEBUG
#define ldm_debug(...) do {} while (0)
#else
#define ldm_debug(f, a...) _ldm_printk (KERN_DEBUG, __func__, f, ##a)
#endif
#define ldm_crit(f, a...) _ldm_printk (KERN_CRIT, __func__, f, ##a)
#define ldm_error(f, a...) _ldm_printk (KERN_ERR, __func__, f, ##a)
#define ldm_info(f, a...) _ldm_printk (KERN_INFO, __func__, f, ##a)
static __printf(3, 4)
void _ldm_printk(const char *level, const char *function, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
va_start (args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
printk("%s%s(): %pV\n", level, function, &vaf);
va_end(args);
}
/**
* 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 (uuid_parse(data + 0x0030, &ph->disk_id)) {
ldm_error("PRIVHEAD contains an invalid GUID.");
return false;
}
ldm_debug("Parsed PRIVHEAD 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_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_compare_privheads - Compare two privhead objects
* @ph1: First privhead
* @ph2: Second privhead
*
* This compares the two privhead structures @ph1 and @ph2.
*
* Return: 'true' Identical
* 'false' Different
*/
static bool ldm_compare_privheads (const struct privhead *ph1,
const struct privhead *ph2)
{
BUG_ON (!ph1 || !ph2);
return ((ph1->ver_major == ph2->ver_major) &&
(ph1->ver_minor == ph2->ver_minor) &&
(ph1->logical_disk_start == ph2->logical_disk_start) &&
(ph1->logical_disk_size == ph2->logical_disk_size) &&
(ph1->config_start == ph2->config_start) &&
(ph1->config_size == ph2->config_size) &&
uuid_equal(&ph1->disk_id, &ph2->disk_id));
}
/**
* ldm_compare_tocblocks - Compare two tocblock objects
* @toc1: First toc
* @toc2: Second toc
*
* This compares the two tocblock structures @toc1 and @toc2.
*
* Return: 'true' Identical
* 'false' Different
*/
static bool ldm_compare_tocblocks (const struct tocblock *toc1,
const struct tocblock *toc2)
{
BUG_ON (!toc1 || !toc2);
return ((toc1->bitmap1_start == toc2->bitmap1_start) &&
(toc1->bitmap1_size == toc2->bitmap1_size) &&
(toc1->bitmap2_start == toc2->bitmap2_start) &&
(toc1->bitmap2_size == toc2->bitmap2_size) &&
!strncmp (toc1->bitmap1_name, toc2->bitmap1_name,
sizeof (toc1->bitmap1_name)) &&
!strncmp (toc1->bitmap2_name, toc2->bitmap2_name,
sizeof (toc1->bitmap2_name)));
}
/**
* 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],
&sect);
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;
}
/**
* 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_array(3, sizeof(*tb[1]), 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], &sect);
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_vmdb - Read the VMDB and validate it
* @state: Partition check state including device holding the LDM Database
* @base: Offset, into @bdev, of the database
* @ldb: Cache of the database structures
*
* Find the vmdb of the LDM Database stored on @bdev and return the parsed
* information in @ldb.
*
* Return: 'true' @ldb contains validated VBDB info
* 'false' @ldb contents are undefined
*/
static bool ldm_validate_vmdb(struct parsed_partitions *state,
unsigned long base, struct ldmdb *ldb)
{
Sector sect;
u8 *data;
bool result = false;
struct vmdb *vm;
struct tocblock *toc;
BUG_ON (!state || !ldb);
vm = &ldb->vm;
toc = &ldb->toc;
data = read_part_sector(state, base + OFF_VMDB, &sect);
if (!data) {
ldm_crit ("Disk read failed.");
return false;
}
if (!ldm_parse_vmdb (data, vm))
goto out; /* Already logged */
/* Are there uncommitted transactions? */
if (get_unaligned_be16(data + 0x10) != 0x01) {
ldm_crit ("Database is not in a consistent state. Aborting.");
goto out;
}
if (vm->vblk_offset != 512)
ldm_info ("VBLKs start at offset 0x%04x.", vm->vblk_offset);
/*
* The last_vblkd_seq can be before the end of the vmdb, just make sure
* it is not out of bounds.
*/
if ((vm->vblk_size * vm->last_vblk_seq) > (toc->bitmap1_size << 9)) {
ldm_crit ("VMDB exceeds allowed size specified by TOCBLOCK. "
"Database is corrupt. Aborting.");
goto out;
}
result = true;
out:
put_dev_sector (sect);
return result;
}
/**
* ldm_validate_partition_table - Determine whether bdev might be a dynamic disk
* @state: Partition check state including device holding the LDM Database
*
* This function provides a weak test to decide whether the device is a dynamic
* disk or not. It looks for an MS-DOS-style partition table containing at
* least one partition of type 0x42 (formerly SFS, now used by Windows for
* dynamic disks).
*
* N.B. The only possible error can come from the read_part_sector and that is
* only likely to happen if the underlying device is strange. If that IS
* the case we should return zero to let someone else try.
*
* Return: 'true' @state->bdev is a dynamic disk
* 'false' @state->bdev is not a dynamic disk, or an error occurred
*/
static bool ldm_validate_partition_table(struct parsed_partitions *state)
{
Sector sect;
u8 *data;
struct msdos_partition *p;
int i;
bool result = false;
BUG_ON(!state);
data = read_part_sector(state, 0, &sect);
if (!data) {
ldm_info ("Disk read failed.");
return false;
}
if (*(__le16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC))
goto out;
p = (struct msdos_partition *)(data + 0x01BE);
for (i = 0; i < 4; i++, p++)
if (SYS_IND (p) == LDM_PARTITION) {
result = true;
break;
}
if (result)
ldm_debug ("Found W2K dynamic disk partition type.");
out:
put_dev_sector (sect);
return result;
}
/**
* ldm_get_disk_objid - Search a linked list of vblk's for a given Disk Id
* @ldb: Cache of the database structures
*
* The LDM Database contains a list of all partitions on all dynamic disks.
* The primary PRIVHEAD, at the beginning of the physical disk, tells us
* the GUID of this disk. This function searches for the GUID in a linked
* list of vblk's.
*
* Return: Pointer, A matching vblk was found
* NULL, No match, or an error
*/
static struct vblk * ldm_get_disk_objid (const struct ldmdb *ldb)
{
struct list_head *item;
BUG_ON (!ldb);
list_for_each (item, &ldb->v_disk) {
struct vblk *v = list_entry (item, struct vblk, list);
if (uuid_equal(&v->vblk.disk.disk_id, &ldb->ph.disk_id))
return v;
}
return NULL;
}
/**
* ldm_create_data_partitions - Create data partitions for this device
* @pp: List of the partitions parsed so far
* @ldb: Cache of the database structures
*
* The database contains ALL the partitions for ALL disk groups, so we need to
* filter out this specific disk. Using the disk's object id, we can find all
* the partitions in the database that belong to this disk.
*
* Add each partition in our database, to the parsed_partitions structure.
*
* N.B. This function creates the partitions in the order it finds partition
* objects in the linked list.
*
* Return: 'true' Partition created
* 'false' Error, probably a range checking problem
*/
static bool ldm_create_data_partitions (struct parsed_partitions *pp,
const struct ldmdb *ldb)
{
struct list_head *item;
struct vblk *vb;
struct vblk *disk;
struct vblk_part *part;
int part_num = 1;
BUG_ON (!pp || !ldb);
disk = ldm_get_disk_objid (ldb);
if (!disk) {
ldm_crit ("Can't find the ID of this disk in the database.");
return false;
}
strlcat(pp->pp_buf, " [LDM]", PAGE_SIZE);
/* Create the data partitions */
list_for_each (item, &ldb->v_part) {
vb = list_entry (item, struct vblk, list);
part = &vb->vblk.part;
if (part->disk_id != disk->obj_id)
continue;
put_partition (pp, part_num, ldb->ph.logical_disk_start +
part->start, part->size);
part_num++;
}
strlcat(pp->pp_buf, "\n", PAGE_SIZE);
return true;
}
/**
* ldm_relative - Calculate the next relative offset
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @base: Size of the previous fixed width fields
* @offset: Cumulative size of the previous variable-width fields
*
* Because many of the VBLK fields are variable-width, it's necessary
* to calculate each offset based on the previous one and the length
* of the field it pointed to.
*
* Return: -1 Error, the calculated offset exceeded the size of the buffer
* n OK, a range-checked offset into buffer
*/
static int ldm_relative(const u8 *buffer, int buflen, int base, int offset)
{
base += offset;
if (!buffer || offset < 0 || base > buflen) {
if (!buffer)
ldm_error("!buffer");
if (offset < 0)
ldm_error("offset (%d) < 0", offset);
if (base > buflen)
ldm_error("base (%d) > buflen (%d)", base, buflen);
return -1;
}
if (base + buffer[base] >= buflen) {
ldm_error("base (%d) + buffer[base] (%d) >= buflen (%d)", base,
buffer[base], buflen);
return -1;
}
return buffer[base] + offset + 1;
}
/**
* ldm_get_vnum - Convert a variable-width, big endian number, into cpu order
* @block: Pointer to the variable-width number to convert
*
* Large numbers in the LDM Database are often stored in a packed format. Each
* number is prefixed by a one byte width marker. All numbers in the database
* are stored in big-endian byte order. This function reads one of these
* numbers and returns the result
*
* N.B. This function DOES NOT perform any range checking, though the most
* it will read is eight bytes.
*
* Return: n A number
* 0 Zero, or an error occurred
*/
static u64 ldm_get_vnum (const u8 *block)
{
u64 tmp = 0;
u8 length;
BUG_ON (!block);
length = *block++;
if (length && length <= 8)
while (length--)
tmp = (tmp << 8) | *block++;
else
ldm_error ("Illegal length %d.", length);
return tmp;
}
/**
* ldm_get_vstr - Read a length-prefixed string into a buffer
* @block: Pointer to the length marker
* @buffer: Location to copy string to
* @buflen: Size of the output buffer
*
* Many of the strings in the LDM Database are not NULL terminated. Instead
* they are prefixed by a one byte length marker. This function copies one of
* these strings into a buffer.
*
* N.B. This function DOES NOT perform any range checking on the input.
* If the buffer is too small, the output will be truncated.
*
* Return: 0, Error and @buffer contents are undefined
* n, String length in characters (excluding NULL)
* buflen-1, String was truncated.
*/
static int ldm_get_vstr (const u8 *block, u8 *buffer, int buflen)
{
int length;
BUG_ON (!block || !buffer);
length = block[0];
if (length >= buflen) {
ldm_error ("Truncating string %d -> %d.", length, buflen);
length = buflen - 1;
}
memcpy (buffer, block + 1, length);
buffer[length] = 0;
return length;
}
/**
* ldm_parse_cmp3 - Read a raw VBLK Component object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Component object (version 3) into a vblk structure.
*
* Return: 'true' @vb contains a Component VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_cmp3 (const u8 *buffer, int buflen, struct vblk *vb)
{
int r_objid, r_name, r_vstate, r_child, r_parent, r_stripe, r_cols, len;
struct vblk_comp *comp;
BUG_ON (!buffer || !vb);
r_objid = ldm_relative (buffer, buflen, 0x18, 0);
r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
r_vstate = ldm_relative (buffer, buflen, 0x18, r_name);
r_child = ldm_relative (buffer, buflen, 0x1D, r_vstate);
r_parent = ldm_relative (buffer, buflen, 0x2D, r_child);
if (buffer[0x12] & VBLK_FLAG_COMP_STRIPE) {
r_stripe = ldm_relative (buffer, buflen, 0x2E, r_parent);
r_cols = ldm_relative (buffer, buflen, 0x2E, r_stripe);
len = r_cols;
} else {
r_stripe = 0;
r_cols = 0;
len = r_parent;
}
if (len < 0)
return false;
len += VBLK_SIZE_CMP3;
if (len != get_unaligned_be32(buffer + 0x14))
return false;
comp = &vb->vblk.comp;
ldm_get_vstr (buffer + 0x18 + r_name, comp->state,
sizeof (comp->state));
comp->type = buffer[0x18 + r_vstate];
comp->children = ldm_get_vnum (buffer + 0x1D + r_vstate);
comp->parent_id = ldm_get_vnum (buffer + 0x2D + r_child);
comp->chunksize = r_stripe ? ldm_get_vnum (buffer+r_parent+0x2E) : 0;
return true;
}
/**
* ldm_parse_dgr3 - Read a raw VBLK Disk Group object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Disk Group object (version 3) into a vblk structure.
*
* Return: 'true' @vb contains a Disk Group VBLK
* 'false' @vb contents are not defined
*/
static int ldm_parse_dgr3 (const u8 *buffer, int buflen, struct vblk *vb)
{
int r_objid, r_name, r_diskid, r_id1, r_id2, len;
struct vblk_dgrp *dgrp;
BUG_ON (!buffer || !vb);
r_objid = ldm_relative (buffer, buflen, 0x18, 0);
r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
if (buffer[0x12] & VBLK_FLAG_DGR3_IDS) {
r_id1 = ldm_relative (buffer, buflen, 0x24, r_diskid);
r_id2 = ldm_relative (buffer, buflen, 0x24, r_id1);
len = r_id2;
} else {
r_id1 = 0;
r_id2 = 0;
len = r_diskid;
}
if (len < 0)
return false;
len += VBLK_SIZE_DGR3;
if (len != get_unaligned_be32(buffer + 0x14))
return false;
dgrp = &vb->vblk.dgrp;
ldm_get_vstr (buffer + 0x18 + r_name, dgrp->disk_id,
sizeof (dgrp->disk_id));
return true;
}
/**
* ldm_parse_dgr4 - Read a raw VBLK Disk Group object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Disk Group object (version 4) into a vblk structure.
*
* Return: 'true' @vb contains a Disk Group VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_dgr4 (const u8 *buffer, int buflen, struct vblk *vb)
{
char buf[64];
int r_objid, r_name, r_id1, r_id2, len;
BUG_ON (!buffer || !vb);
r_objid = ldm_relative (buffer, buflen, 0x18, 0);
r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
if (buffer[0x12] & VBLK_FLAG_DGR4_IDS) {
r_id1 = ldm_relative (buffer, buflen, 0x44, r_name);
r_id2 = ldm_relative (buffer, buflen, 0x44, r_id1);
len = r_id2;
} else {
r_id1 = 0;
r_id2 = 0;
len = r_name;
}
if (len < 0)
return false;
len += VBLK_SIZE_DGR4;
if (len != get_unaligned_be32(buffer + 0x14))
return false;
ldm_get_vstr (buffer + 0x18 + r_objid, buf, sizeof (buf));
return true;
}
/**
* ldm_parse_dsk3 - Read a raw VBLK Disk object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Disk object (version 3) into a vblk structure.
*
* Return: 'true' @vb contains a Disk VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_dsk3 (const u8 *buffer, int buflen, struct vblk *vb)
{
int r_objid, r_name, r_diskid, r_altname, len;
struct vblk_disk *disk;
BUG_ON (!buffer || !vb);
r_objid = ldm_relative (buffer, buflen, 0x18, 0);
r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
r_altname = ldm_relative (buffer, buflen, 0x18, r_diskid);
len = r_altname;
if (len < 0)
return false;
len += VBLK_SIZE_DSK3;
if (len != get_unaligned_be32(buffer + 0x14))
return false;
disk = &vb->vblk.disk;
ldm_get_vstr (buffer + 0x18 + r_diskid, disk->alt_name,
sizeof (disk->alt_name));
if (uuid_parse(buffer + 0x19 + r_name, &disk->disk_id))
return false;
return true;
}
/**
* ldm_parse_dsk4 - Read a raw VBLK Disk object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Disk object (version 4) into a vblk structure.
*
* Return: 'true' @vb contains a Disk VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_dsk4 (const u8 *buffer, int buflen, struct vblk *vb)
{
int r_objid, r_name, len;
struct vblk_disk *disk;
BUG_ON (!buffer || !vb);
r_objid = ldm_relative (buffer, buflen, 0x18, 0);
r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
len = r_name;
if (len < 0)
return false;
len += VBLK_SIZE_DSK4;
if (len != get_unaligned_be32(buffer + 0x14))
return false;
disk = &vb->vblk.disk;
import_uuid(&disk->disk_id, buffer + 0x18 + r_name);
return true;
}
/**
* ldm_parse_prt3 - Read a raw VBLK Partition object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Partition object (version 3) into a vblk structure.
*
* Return: 'true' @vb contains a Partition VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_prt3(const u8 *buffer, int buflen, struct vblk *vb)
{
int r_objid, r_name, r_size, r_parent, r_diskid, r_index, len;
struct vblk_part *part;
BUG_ON(!buffer || !vb);
r_objid = ldm_relative(buffer, buflen, 0x18, 0);
if (r_objid < 0) {
ldm_error("r_objid %d < 0", r_objid);
return false;
}
r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
if (r_name < 0) {
ldm_error("r_name %d < 0", r_name);
return false;
}
r_size = ldm_relative(buffer, buflen, 0x34, r_name);
if (r_size < 0) {
ldm_error("r_size %d < 0", r_size);
return false;
}
r_parent = ldm_relative(buffer, buflen, 0x34, r_size);
if (r_parent < 0) {
ldm_error("r_parent %d < 0", r_parent);
return false;
}
r_diskid = ldm_relative(buffer, buflen, 0x34, r_parent);
if (r_diskid < 0) {
ldm_error("r_diskid %d < 0", r_diskid);
return false;
}
if (buffer[0x12] & VBLK_FLAG_PART_INDEX) {
r_index = ldm_relative(buffer, buflen, 0x34, r_diskid);
if (r_index < 0) {
ldm_error("r_index %d < 0", r_index);
return false;
}
len = r_index;
} else {
r_index = 0;
len = r_diskid;
}
if (len < 0) {
ldm_error("len %d < 0", len);
return false;
}
len += VBLK_SIZE_PRT3;
if (len > get_unaligned_be32(buffer + 0x14)) {
ldm_error("len %d > BE32(buffer + 0x14) %d", len,
get_unaligned_be32(buffer + 0x14));
return false;
}
part = &vb->vblk.part;
part->start = get_unaligned_be64(buffer + 0x24 + r_name);
part->volume_offset = get_unaligned_be64(buffer + 0x2C + r_name);
part->size = ldm_get_vnum(buffer + 0x34 + r_name);
part->parent_id = ldm_get_vnum(buffer + 0x34 + r_size);
part->disk_id = ldm_get_vnum(buffer + 0x34 + r_parent);
if (vb->flags & VBLK_FLAG_PART_INDEX)
part->partnum = buffer[0x35 + r_diskid];
else
part->partnum = 0;
return true;
}
/**
* ldm_parse_vol5 - Read a raw VBLK Volume object into a vblk structure
* @buffer: Block of data being worked on
* @buflen: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK Volume object (version 5) into a vblk structure.
*
* Return: 'true' @vb contains a Volume VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_vol5(const u8 *buffer, int buflen, struct vblk *vb)
{
int r_objid, r_name, r_vtype, r_disable_drive_letter, r_child, r_size;
int r_id1, r_id2, r_size2, r_drive, len;
struct vblk_volu *volu;
BUG_ON(!buffer || !vb);
r_objid = ldm_relative(buffer, buflen, 0x18, 0);
if (r_objid < 0) {
ldm_error("r_objid %d < 0", r_objid);
return false;
}
r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
if (r_name < 0) {
ldm_error("r_name %d < 0", r_name);
return false;
}
r_vtype = ldm_relative(buffer, buflen, 0x18, r_name);
if (r_vtype < 0) {
ldm_error("r_vtype %d < 0", r_vtype);
return false;
}
r_disable_drive_letter = ldm_relative(buffer, buflen, 0x18, r_vtype);
if (r_disable_drive_letter < 0) {
ldm_error("r_disable_drive_letter %d < 0",
r_disable_drive_letter);
return false;
}
r_child = ldm_relative(buffer, buflen, 0x2D, r_disable_drive_letter);
if (r_child < 0) {
ldm_error("r_child %d < 0", r_child);
return false;
}
r_size = ldm_relative(buffer, buflen, 0x3D, r_child);
if (r_size < 0) {
ldm_error("r_size %d < 0", r_size);
return false;
}
if (buffer[0x12] & VBLK_FLAG_VOLU_ID1) {
r_id1 = ldm_relative(buffer, buflen, 0x52, r_size);
if (r_id1 < 0) {
ldm_error("r_id1 %d < 0", r_id1);
return false;
}
} else
r_id1 = r_size;
if (buffer[0x12] & VBLK_FLAG_VOLU_ID2) {
r_id2 = ldm_relative(buffer, buflen, 0x52, r_id1);
if (r_id2 < 0) {
ldm_error("r_id2 %d < 0", r_id2);
return false;
}
} else
r_id2 = r_id1;
if (buffer[0x12] & VBLK_FLAG_VOLU_SIZE) {
r_size2 = ldm_relative(buffer, buflen, 0x52, r_id2);
if (r_size2 < 0) {
ldm_error("r_size2 %d < 0", r_size2);
return false;
}
} else
r_size2 = r_id2;
if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
r_drive = ldm_relative(buffer, buflen, 0x52, r_size2);
if (r_drive < 0) {
ldm_error("r_drive %d < 0", r_drive);
return false;
}
} else
r_drive = r_size2;
len = r_drive;
if (len < 0) {
ldm_error("len %d < 0", len);
return false;
}
len += VBLK_SIZE_VOL5;
if (len > get_unaligned_be32(buffer + 0x14)) {
ldm_error("len %d > BE32(buffer + 0x14) %d", len,
get_unaligned_be32(buffer + 0x14));
return false;
}
volu = &vb->vblk.volu;
ldm_get_vstr(buffer + 0x18 + r_name, volu->volume_type,
sizeof(volu->volume_type));
memcpy(volu->volume_state, buffer + 0x18 + r_disable_drive_letter,
sizeof(volu->volume_state));
volu->size = ldm_get_vnum(buffer + 0x3D + r_child);
volu->partition_type = buffer[0x41 + r_size];
memcpy(volu->guid, buffer + 0x42 + r_size, sizeof(volu->guid));
if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
ldm_get_vstr(buffer + 0x52 + r_size, volu->drive_hint,
sizeof(volu->drive_hint));
}
return true;
}
/**
* ldm_parse_vblk - Read a raw VBLK object into a vblk structure
* @buf: Block of data being worked on
* @len: Size of the block of data
* @vb: In-memory vblk in which to return information
*
* Read a raw VBLK object into a vblk structure. This function just reads the
* information common to all VBLK types, then delegates the rest of the work to
* helper functions: ldm_parse_*.
*
* Return: 'true' @vb contains a VBLK
* 'false' @vb contents are not defined
*/
static bool ldm_parse_vblk (const u8 *buf, int len, struct vblk *vb)
{
bool result = false;
int r_objid;
BUG_ON (!buf || !vb);
r_objid = ldm_relative (buf, len, 0x18, 0);
if (r_objid < 0) {
ldm_error ("VBLK header is corrupt.");
return false;
}
vb->flags = buf[0x12];
vb->type = buf[0x13];
vb->obj_id = ldm_get_vnum (buf + 0x18);
ldm_get_vstr (buf+0x18+r_objid, vb->name, sizeof (vb->name));
switch (vb->type) {
case VBLK_CMP3: result = ldm_parse_cmp3 (buf, len, vb); break;
case VBLK_DSK3: result = ldm_parse_dsk3 (buf, len, vb); break;
case VBLK_DSK4: result = ldm_parse_dsk4 (buf, len, vb); break;
case VBLK_DGR3: result = ldm_parse_dgr3 (buf, len, vb); break;
case VBLK_DGR4: result = ldm_parse_dgr4 (buf, len, vb); break;
case VBLK_PRT3: result = ldm_parse_prt3 (buf, len, vb); break;
case VBLK_VOL5: result = ldm_parse_vol5 (buf, len, vb); break;
}
if (result)
ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.",
(unsigned long long) vb->obj_id, vb->type);
else
ldm_error ("Failed to parse VBLK 0x%llx (type: 0x%02x).",
(unsigned long long) vb->obj_id, vb->type);
return result;
}
/**
* ldm_ldmdb_add - Adds a raw VBLK entry to the ldmdb database
* @data: Raw VBLK to add to the database
* @len: Size of the raw VBLK
* @ldb: Cache of the database structures
*
* The VBLKs are sorted into categories. Partitions are also sorted by offset.
*
* N.B. This function does not check the validity of the VBLKs.
*
* Return: 'true' The VBLK was added
* 'false' An error occurred
*/
static bool ldm_ldmdb_add (u8 *data, int len, struct ldmdb *ldb)
{
struct vblk *vb;
struct list_head *item;
BUG_ON (!data || !ldb);
vb = kmalloc (sizeof (*vb), GFP_KERNEL);
if (!vb) {
ldm_crit ("Out of memory.");
return false;
}
if (!ldm_parse_vblk (data, len, vb)) {
kfree(vb);
return false; /* Already logged */
}
/* Put vblk into the correct list. */
switch (vb->type) {
case VBLK_DGR3:
case VBLK_DGR4:
list_add (&vb->list, &ldb->v_dgrp);
break;
case VBLK_DSK3:
case VBLK_DSK4:
list_add (&vb->list, &ldb->v_disk);
break;
case VBLK_VOL5:
list_add (&vb->list, &ldb->v_volu);
break;
case VBLK_CMP3:
list_add (&vb->list, &ldb->v_comp);
break;
case VBLK_PRT3:
/* Sort by the partition's start sector. */
list_for_each (item, &ldb->v_part) {
struct vblk *v = list_entry (item, struct vblk, list);
if ((v->vblk.part.disk_id == vb->vblk.part.disk_id) &&
(v->vblk.part.start > vb->vblk.part.start)) {
list_add_tail (&vb->list, &v->list);
return true;
}
}
list_add_tail (&vb->list, &ldb->v_part);
break;
}
return true;
}
/**
* ldm_frag_add - Add a VBLK fragment to a list
* @data: Raw fragment to be added to the list
* @size: Size of the raw fragment
* @frags: Linked list of VBLK fragments
*
* Fragmented VBLKs may not be consecutive in the database, so they are placed
* in a list so they can be pieced together later.
*
* Return: 'true' Success, the VBLK was added to the list
* 'false' Error, a problem occurred
*/
static bool ldm_frag_add (const u8 *data, int size, struct list_head *frags)
{
struct frag *f;
struct list_head *item;
int rec, num, group;
BUG_ON (!data || !frags);
if (size < 2 * VBLK_SIZE_HEAD) {
ldm_error("Value of size is too small.");
return false;
}
group = get_unaligned_be32(data + 0x08);
rec = get_unaligned_be16(data + 0x0C);
num = get_unaligned_be16(data + 0x0E);
if ((num < 1) || (num > 4)) {
ldm_error ("A VBLK claims to have %d parts.", num);
return false;
}
if (rec >= num) {
ldm_error("REC value (%d) exceeds NUM value (%d)", rec, num);
return false;
}
list_for_each (item, frags) {
f = list_entry (item, struct frag, list);
if (f->group == group)
goto found;
}
f = kmalloc (sizeof (*f) + size*num, GFP_KERNEL);
if (!f) {
ldm_crit ("Out of memory.");
return false;
}
f->group = group;
f->num = num;
f->rec = rec;
f->map = 0xFF << num;
list_add_tail (&f->list, frags);
found:
if (rec >= f->num) {
ldm_error("REC value (%d) exceeds NUM value (%d)", rec, f->num);
return false;
}
if (f->map & (1 << rec)) {
ldm_error ("Duplicate VBLK, part %d.", rec);
f->map &= 0x7F; /* Mark the group as broken */
return false;
}
f->map |= (1 << rec);
if (!rec)
memcpy(f->data, data, VBLK_SIZE_HEAD);
data += VBLK_SIZE_HEAD;
size -= VBLK_SIZE_HEAD;
memcpy(f->data + VBLK_SIZE_HEAD + rec * size, data, size);
return true;
}
/**
* ldm_frag_free - Free a linked list of VBLK fragments
* @list: Linked list of fragments
*
* Free a linked list of VBLK fragments
*
* Return: none
*/
static void ldm_frag_free (struct list_head *list)
{
struct list_head *item, *tmp;
BUG_ON (!list);
list_for_each_safe (item, tmp, list)
kfree (list_entry (item, struct frag, list));
}
/**
* ldm_frag_commit - Validate fragmented VBLKs and add them to the database
* @frags: Linked list of VBLK fragments
* @ldb: Cache of the database structures
*
* Now that all the fragmented VBLKs have been collected, they must be added to
* the database for later use.
*
* Return: 'true' All the fragments we added successfully
* 'false' One or more of the fragments we invalid
*/
static bool ldm_frag_commit (struct list_head *frags, struct ldmdb *ldb)
{
struct frag *f;
struct list_head *item;
BUG_ON (!frags || !ldb);
list_for_each (item, frags) {
f = list_entry (item, struct frag, list);
if (f->map != 0xFF) {
ldm_error ("VBLK group %d is incomplete (0x%02x).",
f->group, f->map);
return false;
}
if (!ldm_ldmdb_add (f->data, f->num*ldb->vm.vblk_size, ldb))
return false; /* Already logged */
}
return true;
}
/**
* ldm_get_vblks - Read the on-disk database of VBLKs into memory
* @state: Partition check state including device holding the LDM Database
* @base: Offset, into @state->bdev, of the database
* @ldb: Cache of the database structures
*
* To use the information from the VBLKs, they need to be read from the disk,
* unpacked and validated. We cache them in @ldb according to their type.
*
* Return: 'true' All the VBLKs were read successfully
* 'false' An error occurred
*/
static bool ldm_get_vblks(struct parsed_partitions *state, unsigned long base,
struct ldmdb *ldb)
{
int size, perbuf, skip, finish, s, v, recs;
u8 *data = NULL;
Sector sect;
bool result = false;
LIST_HEAD (frags);
BUG_ON(!state || !ldb);
size = ldb->vm.vblk_size;
perbuf = 512 / size;
skip = ldb->vm.vblk_offset >> 9; /* Bytes to sectors */
finish = (size * ldb->vm.last_vblk_seq) >> 9;
for (s = skip; s < finish; s++) { /* For each sector */
data = read_part_sector(state, base + OFF_VMDB + s, &sect);
if (!data) {
ldm_crit ("Disk read failed.");
goto out;
}
for (v = 0; v < perbuf; v++, data+=size) { /* For each vblk */
if (MAGIC_VBLK != get_unaligned_be32(data)) {
ldm_error ("Expected to find a VBLK.");
goto out;
}
recs = get_unaligned_be16(data + 0x0E); /* Number of records */
if (recs == 1) {
if (!ldm_ldmdb_add (data, size, ldb))
goto out; /* Already logged */
} else if (recs > 1) {
if (!ldm_frag_add (data, size, &frags))
goto out; /* Already logged */
}
/* else Record is not in use, ignore it. */
}
put_dev_sector (sect);
data = NULL;
}
result = ldm_frag_commit (&frags, ldb); /* Failures, already logged */
out:
if (data)
put_dev_sector (sect);
ldm_frag_free (&frags);
return result;
}
/**
* ldm_free_vblks - Free a linked list of vblk's
* @lh: Head of a linked list of struct vblk
*
* Free a list of vblk's and free the memory used to maintain the list.
*
* Return: none
*/
static void ldm_free_vblks (struct list_head *lh)
{
struct list_head *item, *tmp;
BUG_ON (!lh);
list_for_each_safe (item, tmp, lh)
kfree (list_entry (item, struct vblk, list));
}
/**
* ldm_partition - Find out whether a device is a dynamic disk and handle it
* @state: Partition check state including device holding the LDM Database
*
* This determines whether the device @bdev is a dynamic disk and if so creates
* the partitions necessary in the gendisk structure pointed to by @hd.
*
* We create a dummy device 1, which contains the LDM database, and then create
* each partition described by the LDM database in sequence as devices 2+. For
* example, if the device is hda, we would have: hda1: LDM database, hda2, hda3,
* and so on: the actual data containing partitions.
*
* Return: 1 Success, @state->bdev is a dynamic disk and we handled it
* 0 Success, @state->bdev is not a dynamic disk
* -1 An error occurred before enough information had been read
* Or @state->bdev is a dynamic disk, but it may be corrupted
*/
int ldm_partition(struct parsed_partitions *state)
{
struct ldmdb *ldb;
unsigned long base;
int result = -1;
BUG_ON(!state);
/* Look for signs of a Dynamic Disk */
if (!ldm_validate_partition_table(state))
return 0;
ldb = kmalloc (sizeof (*ldb), GFP_KERNEL);
if (!ldb) {
ldm_crit ("Out of memory.");
goto out;
}
/* Parse and check privheads. */
if (!ldm_validate_privheads(state, &ldb->ph))
goto out; /* Already logged */
/* All further references are relative to base (database start). */
base = ldb->ph.config_start;
/* Parse and check tocs and vmdb. */
if (!ldm_validate_tocblocks(state, base, ldb) ||
!ldm_validate_vmdb(state, base, ldb))
goto out; /* Already logged */
/* Initialize vblk lists in ldmdb struct */
INIT_LIST_HEAD (&ldb->v_dgrp);
INIT_LIST_HEAD (&ldb->v_disk);
INIT_LIST_HEAD (&ldb->v_volu);
INIT_LIST_HEAD (&ldb->v_comp);
INIT_LIST_HEAD (&ldb->v_part);
if (!ldm_get_vblks(state, base, ldb)) {
ldm_crit ("Failed to read the VBLKs from the database.");
goto cleanup;
}
/* Finally, create the data partition devices. */
if (ldm_create_data_partitions(state, ldb)) {
ldm_debug ("Parsed LDM database successfully.");
result = 1;
}
/* else Already logged */
cleanup:
ldm_free_vblks (&ldb->v_dgrp);
ldm_free_vblks (&ldb->v_disk);
ldm_free_vblks (&ldb->v_volu);
ldm_free_vblks (&ldb->v_comp);
ldm_free_vblks (&ldb->v_part);
out:
kfree (ldb);
return result;
}
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