}	return tmp;}/** * get_vstr - convert a counted, non-null-terminated ASCII string to C-style one * @block:	string to convert * @buffer:	output buffer * @buflen:	size of output buffer * * This converts @block, a counted, non-null-terminated ASCII string, into a * C-style, null-terminated, ASCII string and returns this in @buffer. The * maximum number of characters converted is given by @buflen. * * The first bytes of a counted string stores the length of the string in bytes. * * Return the number of characters written to @buffer, not including the * terminating null character, on success, and -1 on error, in which case * @buffer is not defined. */static int get_vstr(const u8 *block, u8 *buffer, const int buflen){	int length = block[0];	if (length < 1)		return -1;	if (length >= buflen) {		printk(LDM_ERR "String too long for buffer in get_vstr(): "				"(%d/%d). Truncating.\n", length, buflen);		length = buflen - 1;	}	memcpy(buffer, block + 1, length);	buffer[length] = (u8)'\0';	return length;}/** * get_disk_objid - obtain the object id for the device we are working on * @dev:	partition device holding the LDM database * @vm:		in memory vmdb structure of the LDM database * @ph:		in memory privhead structure of the device we are working on * @dk:		in memory ldmdisk structure to return information into * * This obtains the object id for the device we are working on as defined by * the private header @ph. The obtained object id, together with the disk's * GUID from @ph are returned in the ldmdisk structure pointed to by @dk. * * A Disk has two Ids. The main one is a GUID in string format. The second, * used internally for cross-referencing, is a small, sequentially allocated, * number. The PRIVHEAD, just after the partition table, tells us the disk's * GUID. To find the disk's object id, we have to look through the database. * * Return 1 on success and -1 on error, in which case @dk is undefined. */static int get_disk_objid(struct block_device *bdev, const struct vmdb *vm,		const struct privhead *ph, struct ldmdisk *dk,		unsigned long base){	Sector sect;	unsigned char *data;	u8 *disk_id;	int vblk;	int vsize;		/* VBLK size. */	int perbuf;		/* VBLKs per buffer. */	int buffer, lastbuf, lastofs, err;	disk_id = (u8*)kmalloc(DISK_ID_SIZE, GFP_KERNEL);	if (!disk_id)		goto no_mem;	vsize   = vm->vblk_size;	if (vsize < 1 || vsize > 512)		goto err_out;	perbuf  = 512 / vsize;	if (perbuf < 1 || 512 % vsize)		goto err_out;					/* 512 == VMDB size */	lastbuf = vm->last_vblk_seq / perbuf - 1;	lastofs = vm->last_vblk_seq % perbuf;	if (lastofs)		lastbuf++;	if (OFF_VBLK * LDM_BLOCKSIZE + vm->last_vblk_seq * vsize >			ph->config_size * 512)		goto err_out;	for (buffer = 0; buffer < lastbuf; buffer++) {		data = read_dev_sector(bdev, base + 2*OFF_VBLK + buffer, &sect);		if (!data)			goto read_err;		for (vblk = 0; vblk < perbuf; vblk++) {			int rel_objid, rel_name, delta;			u8 *block;			if (lastofs && buffer == lastbuf - 1 && vblk >= lastofs)				break;			block = data + vblk * vsize;			delta = vblk * vsize + 0x18;			if (delta >= 512)				goto brelse_out;			if (block[0x0D] != 0)	/* Extended VBLK, ignore */				continue;			if ((block[0x13] != VBLK_DSK1) &&			    (block[0x13] != VBLK_DSK2))				continue;			/* Calculate relative offsets. */			rel_objid = 1 + block[0x18];			if (delta + rel_objid >= 512)				goto brelse_out;			rel_name  = 1 + block[0x18 + rel_objid] + rel_objid;			if (delta + rel_name >= 512 ||			    delta + rel_name + block[0x18 + rel_name] >= 512)				goto brelse_out;			err = get_vstr(block + 0x18 + rel_name, disk_id,					DISK_ID_SIZE);			if (err == -1)				goto brelse_out;			if (!strncmp(disk_id, ph->disk_id, DISK_ID_SIZE)) {				dk->obj_id = get_vnum(block + 0x18, &err);				put_dev_sector(sect);				if (err)					goto out;				strncpy(dk->disk_id, ph->disk_id,						sizeof(dk->disk_id));				dk->disk_id[sizeof(dk->disk_id) - 1] = (u8)'\0';				err = 1;				goto out;			}		}		put_dev_sector(sect);	}	err = -1;out:	kfree(disk_id);	return err;brelse_out:	put_dev_sector(sect);	goto err_out;no_mem:	printk(LDM_CRIT "Not enough memory to allocate required buffers.\n");	goto err_out;read_err:	printk(LDM_CRIT "Disk read failed in get_disk_objid.\n");err_out:	err = -1;	goto out;}/** * parse_vmdb - parse the LDM database vmdb structure * @buffer:	LDM database vmdb structure loaded from the device * @vm:		in memory vmdb structure to return parsed information in * * This parses the LDM database vmdb structure supplied in @buffer and sets up * the in memory vmdb structure @vm with the obtained information. * * Return 1 on success and -1 on error, in which case @vm is undefined. * * NOTE: The *_start, *_size and *_seq values returned in @vm have not been * checked for validity, so make sure to check them when using them. */static int parse_vmdb(const u8 *buffer, struct vmdb *vm){	if (MAGIC_VMDB != BE32(buffer)) {		printk(LDM_CRIT "Cannot find VMDB, database may be corrupt.\n");		return -1;	}	vm->ver_major = BE16(buffer + 0x12);	vm->ver_minor = BE16(buffer + 0x14);	if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {		printk(LDM_ERR "Expected VMDB version %d.%d, got %d.%d. "				"Aborting.\n", 4, 10, vm->ver_major,				vm->ver_minor);		return -1;	}	vm->vblk_size	  = BE32(buffer + 0x08);	vm->vblk_offset   = BE32(buffer + 0x0C);	vm->last_vblk_seq = BE32(buffer + 0x04);	ldm_debug("Parsed VMDB successfully.\n");	return 1;}/** * validate_vmdb - validate the vmdb * @dev:	partition device holding the LDM database * @vm:		in memory vmdb in which to return information * * Find the vmdb of the LDM database stored on @dev and return the parsed * information into @vm. * * Return 1 on success and -1 on error, in which case @vm is undefined. */static int validate_vmdb(struct block_device *bdev, struct vmdb *vm, unsigned long base){	Sector sect;	unsigned char *data;	int ret;	data = read_dev_sector(bdev, base + OFF_VMDB * 2 + 1, &sect);	if (!data) {		printk(LDM_CRIT "Disk read failed in validate_vmdb.\n");		return -1;	}	ret = parse_vmdb(data, vm);	put_dev_sector(sect);	return ret;}/** * compare_tocblocks - compare two tables of contents * @toc1:	first toc * @toc2:	second toc * * This compares the two tables of contents @toc1 and @toc2. * * Return 1 if @toc1 and @toc2 are equal and -1 otherwise. */static int compare_tocblocks(const struct tocblock *toc1,		const struct tocblock *toc2){	if ((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)))		return 1;	return -1;}/** * parse_tocblock - parse the LDM database table of contents structure * @buffer:	LDM database toc structure loaded from the device * @toc:	in memory toc structure to return parsed information in * * This parses the LDM database table of contents structure supplied in @buffer * and sets up the in memory table of contents structure @toc with the obtained * information. * * Return 1 on success and -1 on error, in which case @toc is undefined. * * FIXME: The *_start and *_size values returned in @toc are not been checked * for validity but as we don't use the actual values for anything other than * comparing between the toc and its backups, the values are not important. */static int parse_tocblock(const u8 *buffer, struct tocblock *toc){	if (MAGIC_TOCBLOCK != BE64(buffer)) {		printk(LDM_CRIT "Cannot find TOCBLOCK, database may be "				"corrupt.\n");		return -1;	}	strncpy(toc->bitmap1_name, buffer + 0x24, sizeof(toc->bitmap1_name));	toc->bitmap1_name[sizeof(toc->bitmap1_name) - 1] = (u8)'\0';	toc->bitmap1_start = BE64(buffer + 0x2E);	toc->bitmap1_size  = BE64(buffer + 0x36);	/*toc->bitmap1_flags = BE64(buffer + 0x3E);*/	if (strncmp(toc->bitmap1_name, TOC_BITMAP1,			sizeof(toc->bitmap1_name)) != 0) {		printk(LDM_CRIT "TOCBLOCK's first bitmap should be %s, but is "				"%s.\n", TOC_BITMAP1, toc->bitmap1_name);		return -1;	}	strncpy(toc->bitmap2_name, buffer + 0x46, sizeof(toc->bitmap2_name));	toc->bitmap2_name[sizeof(toc->bitmap2_name) - 1] = (u8)'\0';	toc->bitmap2_start = BE64(buffer + 0x50);	toc->bitmap2_size  = BE64(buffer + 0x58);	/*toc->bitmap2_flags = BE64(buffer + 0x60);*/	if (strncmp(toc->bitmap2_name, TOC_BITMAP2,			sizeof(toc->bitmap2_name)) != 0) {		printk(LDM_CRIT "TOCBLOCK's second bitmap should be %s, but is "				"%s.\n", TOC_BITMAP2, toc->bitmap2_name);		return -1;	}	ldm_debug("Parsed TOCBLOCK successfully.\n");	return 1;}/** * validate_tocblocks - validate the table of contents and its backups * @dev:	partition device holding the LDM database * @toc1:	in memory table of contents in which to return information * * Find and compare the four tables of contents of the LDM database stored on * @dev and return the parsed information into @toc1. * * Return 1 on success and -1 on error, in which case @toc1 is undefined. */static int validate_tocblocks(struct block_device *bdev,			struct tocblock *toc1,			unsigned long base){	Sector sect;	unsigned char *data;	struct tocblock *toc2 = NULL, *toc3 = NULL, *toc4 = NULL;	int err;	toc2 = (struct tocblock*)kmalloc(sizeof(*toc2), GFP_KERNEL);	if (!toc2)		goto no_mem;	toc3 = (struct tocblock*)kmalloc(sizeof(*toc3), GFP_KERNEL);	if (!toc3)		goto no_mem;	toc4 = (struct tocblock*)kmalloc(sizeof(*toc4), GFP_KERNEL);	if (!toc4)		goto no_mem;	/* Read and parse first toc. */	data = read_dev_sector(bdev, base + OFF_TOCBLOCK1 * 2 + 1, &sect);	if (!data) {		printk(LDM_CRIT "Disk read 1 failed in validate_tocblocks.\n");		goto err_out;	}	err = parse_tocblock(data, toc1);	put_dev_sector(sect);	if (err != 1)		goto out;	/* Read and parse second toc. */	data = read_dev_sector(bdev, base + OFF_TOCBLOCK2 * 2, &sect);	if (!data) {		printk(LDM_CRIT "Disk read 2 failed in validate_tocblocks.\n");		goto err_out;	}	err = parse_tocblock(data, toc2);	put_dev_sector(sect);	if (err != 1)		goto out;	/* Read and parse third toc. */	data = read_dev_sector(bdev, base + OFF_TOCBLOCK3 * 2 + 1, &sect);	if (!data) {		printk(LDM_CRIT "Disk read 3 failed in validate_tocblocks.\n");		goto err_out;	}	err = parse_tocblock(data, toc3);	put_dev_sector(sect);	if (err != 1)		goto out;	/* Read and parse fourth toc. */	data = read_dev_sector(bdev, base + OFF_TOCBLOCK4 * 2, &sect);	if (!data) {		printk(LDM_CRIT "Disk read 4 failed in validate_tocblocks.\n");		goto err_out;	}	err = parse_tocblock(data, toc4);	put_dev_sector(sect);	if (err != 1)		goto out;	/* Compare all tocs. */	err = compare_tocblocks(toc1, toc2);	if (err != 1) {		printk(LDM_CRIT "First and second TOCBLOCKs don't match.\n");		goto out;	}	err = compare_tocblocks(toc3, toc4);	if (err != 1) {		printk(LDM_CRIT "Third and fourth TOCBLOCKs don't match.\n");		goto out;	}	err = compare_tocblocks(toc1, toc3);