probe.c revision b41fb002257d4b997560cd77676b78219be03c24
1/*
2 * probe.c - identify a block device by its contents, and return a dev
3 *           struct with the details
4 *
5 * Copyright (C) 1999 by Andries Brouwer
6 * Copyright (C) 1999, 2000, 2003 by Theodore Ts'o
7 * Copyright (C) 2001 by Andreas Dilger
8 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
9 *
10 * %Begin-Header%
11 * This file may be redistributed under the terms of the
12 * GNU Lesser General Public License.
13 * %End-Header%
14 */
15
16#include <stdio.h>
17#include <string.h>
18#include <stdlib.h>
19#include <unistd.h>
20#include <fcntl.h>
21#include <ctype.h>
22#include <sys/types.h>
23#ifdef HAVE_SYS_STAT_H
24#include <sys/stat.h>
25#endif
26#ifdef HAVE_SYS_MKDEV_H
27#include <sys/mkdev.h>
28#endif
29#include <sys/utsname.h>
30#ifdef HAVE_ERRNO_H
31#include <errno.h>
32#endif
33#include "blkidP.h"
34#include "uuid/uuid.h"
35#include "probe.h"
36
37static int figure_label_len(const unsigned char *label, int len)
38{
39	const unsigned char *end = label + len - 1;
40
41	while ((*end == ' ' || *end == 0) && end >= label)
42		--end;
43	if (end >= label) {
44		label = label;
45		return end - label + 1;
46	}
47	return 0;
48}
49
50static unsigned char *get_buffer(struct blkid_probe *pr,
51			  blkid_loff_t off, size_t len)
52{
53	ssize_t		ret_read;
54	unsigned char	*newbuf;
55
56	if (off + len <= SB_BUFFER_SIZE) {
57		if (!pr->sbbuf) {
58			pr->sbbuf = malloc(SB_BUFFER_SIZE);
59			if (!pr->sbbuf)
60				return NULL;
61			if (lseek(pr->fd, 0, SEEK_SET) < 0)
62				return NULL;
63			ret_read = read(pr->fd, pr->sbbuf, SB_BUFFER_SIZE);
64			if (ret_read < 0)
65				ret_read = 0;
66			pr->sb_valid = ret_read;
67		}
68		if (off+len > pr->sb_valid)
69			return NULL;
70		return pr->sbbuf + off;
71	} else {
72		if (len > pr->buf_max) {
73			newbuf = realloc(pr->buf, len);
74			if (newbuf == NULL)
75				return NULL;
76			pr->buf = newbuf;
77			pr->buf_max = len;
78		}
79		if (blkid_llseek(pr->fd, off, SEEK_SET) < 0)
80			return NULL;
81		ret_read = read(pr->fd, pr->buf, len);
82		if (ret_read != (ssize_t) len)
83			return NULL;
84		return pr->buf;
85	}
86}
87
88
89/*
90 * This is a special case code to check for an MDRAID device.  We do
91 * this special since it requires checking for a superblock at the end
92 * of the device.
93 */
94static int check_mdraid(int fd, unsigned char *ret_uuid)
95{
96	struct mdp_superblock_s *md;
97	blkid_loff_t		offset;
98	char			buf[4096];
99
100	if (fd < 0)
101		return -BLKID_ERR_PARAM;
102
103	offset = (blkid_get_dev_size(fd) & ~((blkid_loff_t)65535)) - 65536;
104
105	if (blkid_llseek(fd, offset, 0) < 0 ||
106	    read(fd, buf, 4096) != 4096)
107		return -BLKID_ERR_IO;
108
109	/* Check for magic number */
110	if (memcmp("\251+N\374", buf, 4) && memcmp("\374N+\251", buf, 4))
111		return -BLKID_ERR_PARAM;
112
113	if (!ret_uuid)
114		return 0;
115	*ret_uuid = 0;
116
117	/* The MD UUID is not contiguous in the superblock, make it so */
118	md = (struct mdp_superblock_s *)buf;
119	if (md->set_uuid0 || md->set_uuid1 || md->set_uuid2 || md->set_uuid3) {
120		memcpy(ret_uuid, &md->set_uuid0, 4);
121		memcpy(ret_uuid + 4, &md->set_uuid1, 12);
122	}
123	return 0;
124}
125
126static void set_uuid(blkid_dev dev, uuid_t uuid, const char *tag)
127{
128	char	str[37];
129
130	if (!uuid_is_null(uuid)) {
131		uuid_unparse(uuid, str);
132		blkid_set_tag(dev, tag ? tag : "UUID", str, sizeof(str));
133	}
134}
135
136static void get_ext2_info(blkid_dev dev, struct blkid_magic *id,
137			  unsigned char *buf)
138{
139	struct ext2_super_block *es = (struct ext2_super_block *) buf;
140	const char *label = 0;
141
142	DBG(DEBUG_PROBE, printf("ext2_sb.compat = %08X:%08X:%08X\n",
143		   blkid_le32(es->s_feature_compat),
144		   blkid_le32(es->s_feature_incompat),
145		   blkid_le32(es->s_feature_ro_compat)));
146
147	if (strlen(es->s_volume_name))
148		label = es->s_volume_name;
149	blkid_set_tag(dev, "LABEL", label, sizeof(es->s_volume_name));
150
151	set_uuid(dev, es->s_uuid, 0);
152
153	if ((es->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
154	    !uuid_is_null(es->s_journal_uuid))
155		set_uuid(dev, es->s_journal_uuid, "EXT_JOURNAL");
156
157	if (strcmp(id->bim_type, "ext2") &&
158	    ((blkid_le32(es->s_feature_incompat) &
159	      EXT2_FEATURE_INCOMPAT_UNSUPPORTED) == 0))
160		blkid_set_tag(dev, "SEC_TYPE", "ext2", sizeof("ext2"));
161}
162
163/*
164 * Check to see if a filesystem is in /proc/filesystems.
165 * Returns 1 if found, 0 if not
166 */
167static int fs_proc_check(const char *fs_name)
168{
169	FILE	*f;
170	char	buf[80], *cp, *t;
171
172	f = fopen("/proc/filesystems", "r");
173	if (!f)
174		return (0);
175	while (!feof(f)) {
176		if (!fgets(buf, sizeof(buf), f))
177			break;
178		cp = buf;
179		if (!isspace(*cp)) {
180			while (*cp && !isspace(*cp))
181				cp++;
182		}
183		while (*cp && isspace(*cp))
184			cp++;
185		if ((t = strchr(cp, '\n')) != NULL)
186			*t = 0;
187		if ((t = strchr(cp, '\t')) != NULL)
188			*t = 0;
189		if ((t = strchr(cp, ' ')) != NULL)
190			*t = 0;
191		if (!strcmp(fs_name, cp)) {
192			fclose(f);
193			return (1);
194		}
195	}
196	fclose(f);
197	return (0);
198}
199
200/*
201 * Check to see if a filesystem is available as a module
202 * Returns 1 if found, 0 if not
203 */
204static int check_for_modules(const char *fs_name)
205{
206	struct utsname	uts;
207	FILE		*f;
208	char		buf[1024], *cp, *t;
209	int		i;
210
211	if (uname(&uts))
212		return (0);
213	snprintf(buf, sizeof(buf), "/lib/modules/%s/modules.dep", uts.release);
214
215	f = fopen(buf, "r");
216	if (!f)
217		return (0);
218	while (!feof(f)) {
219		if (!fgets(buf, sizeof(buf), f))
220			break;
221		if ((cp = strchr(buf, ':')) != NULL)
222			*cp = 0;
223		else
224			continue;
225		if ((cp = strrchr(buf, '/')) != NULL)
226			cp++;
227		i = strlen(cp);
228		if (i > 3) {
229			t = cp + i - 3;
230			if (!strcmp(t, ".ko"))
231				*t = 0;
232		}
233		if (!strcmp(cp, fs_name))
234			return (1);
235	}
236	fclose(f);
237	return (0);
238}
239
240static int system_supports_ext4(void)
241{
242	static time_t	last_check = 0;
243	static int	ret = -1;
244	time_t		now = time(0);
245
246	if (ret != -1 || (last_check - now) < 5)
247		return ret;
248	last_check = now;
249	ret = (fs_proc_check("ext4") || check_for_modules("ext4"));
250	return ret;
251}
252
253static int system_supports_ext4dev(void)
254{
255	static time_t	last_check = 0;
256	static int	ret = -1;
257	time_t		now = time(0);
258
259	if (ret != -1 || (last_check - now) < 5)
260		return ret;
261	last_check = now;
262	ret = (fs_proc_check("ext4dev") || check_for_modules("ext4dev"));
263	return ret;
264}
265
266static int probe_ext4dev(struct blkid_probe *probe,
267			 struct blkid_magic *id,
268			 unsigned char *buf)
269{
270	struct ext2_super_block *es;
271	es = (struct ext2_super_block *)buf;
272
273	/* Distinguish from jbd */
274	if (blkid_le32(es->s_feature_incompat) &
275	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
276		return -BLKID_ERR_PARAM;
277
278	/* ext4dev requires a journal */
279	if (!(blkid_le32(es->s_feature_compat) &
280	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
281		return -BLKID_ERR_PARAM;
282
283	/*
284	 * If the filesystem is marked as OK for use by in-development
285	 * filesystem code, but ext4dev is not supported, and ext4 is,
286	 * then don't call ourselves ext4dev, since we should be
287	 * detected as ext4 in that case.
288	 *
289	 * If the filesystem is marked as in use by production
290	 * filesystem, then it can only be used by ext4 and NOT by
291	 * ext4dev, so always disclaim we are ext4dev in that case.
292	 */
293	if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS) {
294		if (!system_supports_ext4dev() && system_supports_ext4())
295			return -BLKID_ERR_PARAM;
296	} else
297		return -BLKID_ERR_PARAM;
298
299    	get_ext2_info(probe->dev, id, buf);
300	return 0;
301}
302
303static int probe_ext4(struct blkid_probe *probe, struct blkid_magic *id,
304		      unsigned char *buf)
305{
306	struct ext2_super_block *es;
307	es = (struct ext2_super_block *)buf;
308
309	/* Distinguish from jbd */
310	if (blkid_le32(es->s_feature_incompat) &
311	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
312		return -BLKID_ERR_PARAM;
313
314	/* ext4 requires journal */
315	if (!(blkid_le32(es->s_feature_compat) &
316	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
317		return -BLKID_ERR_PARAM;
318
319	/* Ext4 has at least one feature which ext3 doesn't understand */
320	if (!(blkid_le32(es->s_feature_ro_compat) &
321	      EXT3_FEATURE_RO_COMPAT_UNSUPPORTED) &&
322	    !(blkid_le32(es->s_feature_incompat) &
323	      EXT3_FEATURE_INCOMPAT_UNSUPPORTED))
324		return -BLKID_ERR_PARAM;
325
326	/*
327	 * If the filesystem is a OK for use by in-development
328	 * filesystem code, and ext4dev is supported or ext4 is not
329	 * supported, then don't call ourselves ext4, so we can redo
330	 * the detection and mark the filesystem as ext4dev.
331	 *
332	 * If the filesystem is marked as in use by production
333	 * filesystem, then it can only be used by ext4 and NOT by
334	 * ext4dev.
335	 */
336	if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS) {
337		if (system_supports_ext4dev() || !system_supports_ext4())
338			return -BLKID_ERR_PARAM;
339	}
340    	get_ext2_info(probe->dev, id, buf);
341	return 0;
342}
343
344static int probe_ext3(struct blkid_probe *probe, struct blkid_magic *id,
345		      unsigned char *buf)
346{
347	struct ext2_super_block *es;
348	es = (struct ext2_super_block *)buf;
349
350	/* Distinguish from ext4dev */
351	if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS)
352		return -BLKID_ERR_PARAM;
353
354	/* ext3 requires journal */
355	if (!(blkid_le32(es->s_feature_compat) &
356	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
357		return -BLKID_ERR_PARAM;
358
359	/* Any features which ext3 doesn't understand */
360	if ((blkid_le32(es->s_feature_ro_compat) &
361	     EXT3_FEATURE_RO_COMPAT_UNSUPPORTED) ||
362	    (blkid_le32(es->s_feature_incompat) &
363	     EXT3_FEATURE_INCOMPAT_UNSUPPORTED))
364		return -BLKID_ERR_PARAM;
365
366    	get_ext2_info(probe->dev, id, buf);
367	return 0;
368}
369
370static int probe_ext2(struct blkid_probe *probe, struct blkid_magic *id,
371		      unsigned char *buf)
372{
373	struct ext2_super_block *es;
374
375	es = (struct ext2_super_block *)buf;
376
377	/* Distinguish between ext3 and ext2 */
378	if ((blkid_le32(es->s_feature_compat) &
379	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
380		return -BLKID_ERR_PARAM;
381
382	/* Any features which ext2 doesn't understand */
383	if ((blkid_le32(es->s_feature_ro_compat) &
384	     EXT2_FEATURE_RO_COMPAT_UNSUPPORTED) ||
385	    (blkid_le32(es->s_feature_incompat) &
386	     EXT2_FEATURE_INCOMPAT_UNSUPPORTED))
387		return -BLKID_ERR_PARAM;
388
389	get_ext2_info(probe->dev, id, buf);
390	return 0;
391}
392
393static int probe_jbd(struct blkid_probe *probe, struct blkid_magic *id,
394		     unsigned char *buf)
395{
396	struct ext2_super_block *es = (struct ext2_super_block *) buf;
397
398	if (!(blkid_le32(es->s_feature_incompat) &
399	      EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
400		return -BLKID_ERR_PARAM;
401
402	get_ext2_info(probe->dev, id, buf);
403
404	return 0;
405}
406
407#define FAT_ATTR_VOLUME_ID		0x08
408#define FAT_ATTR_DIR			0x10
409#define FAT_ATTR_LONG_NAME		0x0f
410#define FAT_ATTR_MASK			0x3f
411#define FAT_ENTRY_FREE			0xe5
412
413static const char *no_name = "NO NAME    ";
414
415static unsigned char *search_fat_label(struct vfat_dir_entry *dir, int count)
416{
417	int i;
418
419	for (i = 0; i < count; i++) {
420		if (dir[i].name[0] == 0x00)
421			break;
422
423		if ((dir[i].name[0] == FAT_ENTRY_FREE) ||
424		    (dir[i].cluster_high != 0 || dir[i].cluster_low != 0) ||
425		    ((dir[i].attr & FAT_ATTR_MASK) == FAT_ATTR_LONG_NAME))
426			continue;
427
428		if ((dir[i].attr & (FAT_ATTR_VOLUME_ID | FAT_ATTR_DIR)) ==
429		    FAT_ATTR_VOLUME_ID) {
430			return dir[i].name;
431		}
432	}
433	return 0;
434}
435
436/* FAT label extraction from the root directory taken from Kay
437 * Sievers's volume_id library */
438static int probe_fat(struct blkid_probe *probe,
439		      struct blkid_magic *id __BLKID_ATTR((unused)),
440		      unsigned char *buf)
441{
442	struct vfat_super_block *vs = (struct vfat_super_block *) buf;
443	struct msdos_super_block *ms = (struct msdos_super_block *) buf;
444	struct vfat_dir_entry *dir;
445	char serno[10];
446	const unsigned char *label = 0, *vol_label = 0, *tmp;
447	unsigned char	*vol_serno;
448	int label_len = 0, maxloop = 100;
449	__u16 sector_size, dir_entries, reserved;
450	__u32 sect_count, fat_size, dir_size, cluster_count, fat_length;
451	__u32 buf_size, start_data_sect, next, root_start, root_dir_entries;
452
453	/* sector size check */
454	tmp = (unsigned char *)&ms->ms_sector_size;
455	sector_size = tmp[0] + (tmp[1] << 8);
456	if (sector_size != 0x200 && sector_size != 0x400 &&
457	    sector_size != 0x800 && sector_size != 0x1000)
458		return 1;
459
460	tmp = (unsigned char *)&ms->ms_dir_entries;
461	dir_entries = tmp[0] + (tmp[1] << 8);
462	reserved =  blkid_le16(ms->ms_reserved);
463	tmp = (unsigned char *)&ms->ms_sectors;
464	sect_count = tmp[0] + (tmp[1] << 8);
465	if (sect_count == 0)
466		sect_count = blkid_le32(ms->ms_total_sect);
467
468	fat_length = blkid_le16(ms->ms_fat_length);
469	if (fat_length == 0)
470		fat_length = blkid_le32(vs->vs_fat32_length);
471
472	fat_size = fat_length * ms->ms_fats;
473	dir_size = ((dir_entries * sizeof(struct vfat_dir_entry)) +
474			(sector_size-1)) / sector_size;
475
476	cluster_count = sect_count - (reserved + fat_size + dir_size);
477	if (ms->ms_cluster_size == 0)
478		return 1;
479	cluster_count /= ms->ms_cluster_size;
480
481	if (cluster_count > FAT32_MAX)
482		return 1;
483
484	if (ms->ms_fat_length) {
485		/* the label may be an attribute in the root directory */
486		root_start = (reserved + fat_size) * sector_size;
487		root_dir_entries = vs->vs_dir_entries[0] +
488			(vs->vs_dir_entries[1] << 8);
489
490		buf_size = root_dir_entries * sizeof(struct vfat_dir_entry);
491		dir = (struct vfat_dir_entry *) get_buffer(probe, root_start,
492							   buf_size);
493		if (dir)
494			vol_label = search_fat_label(dir, root_dir_entries);
495
496		if (!vol_label || !memcmp(vol_label, no_name, 11))
497			vol_label = ms->ms_label;
498		vol_serno = ms->ms_serno;
499
500		blkid_set_tag(probe->dev, "SEC_TYPE", "msdos",
501			      sizeof("msdos"));
502	} else {
503		/* Search the FAT32 root dir for the label attribute */
504		buf_size = vs->vs_cluster_size * sector_size;
505		start_data_sect = reserved + fat_size;
506
507		next = blkid_le32(vs->vs_root_cluster);
508		while (next && --maxloop) {
509			__u32 next_sect_off;
510			__u64 next_off, fat_entry_off;
511			int count;
512
513			next_sect_off = (next - 2) * vs->vs_cluster_size;
514			next_off = (start_data_sect + next_sect_off) *
515				sector_size;
516
517			dir = (struct vfat_dir_entry *)
518				get_buffer(probe, next_off, buf_size);
519			if (dir == NULL)
520				break;
521
522			count = buf_size / sizeof(struct vfat_dir_entry);
523
524			vol_label = search_fat_label(dir, count);
525			if (vol_label)
526				break;
527
528			/* get FAT entry */
529			fat_entry_off = (reserved * sector_size) +
530				(next * sizeof(__u32));
531			buf = get_buffer(probe, fat_entry_off, buf_size);
532			if (buf == NULL)
533				break;
534
535			/* set next cluster */
536			next = blkid_le32(*((__u32 *) buf) & 0x0fffffff);
537		}
538
539		if (!vol_label || !memcmp(vol_label, no_name, 11))
540			vol_label = vs->vs_label;
541		vol_serno = vs->vs_serno;
542	}
543
544	if (vol_label && memcmp(vol_label, no_name, 11)) {
545		if ((label_len = figure_label_len(vol_label, 11)))
546			label = vol_label;
547	}
548
549	/* We can't just print them as %04X, because they are unaligned */
550	sprintf(serno, "%02X%02X-%02X%02X", vol_serno[3], vol_serno[2],
551		vol_serno[1], vol_serno[0]);
552
553	blkid_set_tag(probe->dev, "LABEL", (const char *) label, label_len);
554	blkid_set_tag(probe->dev, "UUID", serno, sizeof(serno)-1);
555
556	return 0;
557}
558
559/*
560 * The FAT filesystem could be without a magic string in superblock
561 * (e.g. old floppies).  This heuristic for FAT detection is inspired
562 * by http://vrfy.org/projects/volume_id/ and Linux kernel.
563 * [7-Jul-2005, Karel Zak <kzak@redhat.com>]
564 */
565static int probe_fat_nomagic(struct blkid_probe *probe,
566			     struct blkid_magic *id __BLKID_ATTR((unused)),
567			     unsigned char *buf)
568{
569	struct msdos_super_block *ms;
570
571	ms = (struct msdos_super_block *)buf;
572
573	/* heads check */
574	if (ms->ms_heads == 0)
575		return 1;
576
577	/* cluster size check*/
578	if (ms->ms_cluster_size == 0 ||
579	    (ms->ms_cluster_size & (ms->ms_cluster_size-1)))
580		return 1;
581
582	/* media check */
583	if (ms->ms_media < 0xf8 && ms->ms_media != 0xf0)
584		return 1;
585
586	/* fat counts(Linux kernel expects at least 1 FAT table) */
587	if (!ms->ms_fats)
588		return 1;
589
590	/*
591	 * OS/2 and apparently DFSee will place a FAT12/16-like
592	 * pseudo-superblock in the first 512 bytes of non-FAT
593	 * filesystems --- at least JFS and HPFS, and possibly others.
594	 * So we explicitly check for those filesystems at the
595	 * FAT12/16 filesystem magic field identifier, and if they are
596	 * present, we rule this out as a FAT filesystem, despite the
597	 * FAT-like pseudo-header.
598         */
599	if ((memcmp(ms->ms_magic, "JFS     ", 8) == 0) ||
600	    (memcmp(ms->ms_magic, "HPFS    ", 8) == 0))
601		return 1;
602
603	return probe_fat(probe, id, buf);
604}
605
606static int probe_ntfs(struct blkid_probe *probe,
607		      struct blkid_magic *id __BLKID_ATTR((unused)),
608		      unsigned char *buf)
609{
610	struct ntfs_super_block *ns;
611	struct master_file_table_record *mft;
612	struct file_attribute *attr;
613	char		uuid_str[17], label_str[129], *cp;
614	int		bytes_per_sector, sectors_per_cluster;
615	int		mft_record_size, attr_off, attr_len;
616	unsigned int	i, attr_type, val_len;
617	int		val_off;
618	__u64		nr_clusters;
619	blkid_loff_t off;
620	unsigned char *buf_mft, *val;
621
622	ns = (struct ntfs_super_block *) buf;
623
624	bytes_per_sector = ns->bios_parameter_block[0] +
625		(ns->bios_parameter_block[1]  << 8);
626	sectors_per_cluster = ns->bios_parameter_block[2];
627
628	if ((bytes_per_sector < 512) || (sectors_per_cluster == 0))
629		return 1;
630
631	if (ns->cluster_per_mft_record < 0)
632		mft_record_size = 1 << (0-ns->cluster_per_mft_record);
633	else
634		mft_record_size = ns->cluster_per_mft_record *
635			sectors_per_cluster * bytes_per_sector;
636	nr_clusters = blkid_le64(ns->number_of_sectors) / sectors_per_cluster;
637
638	if ((blkid_le64(ns->mft_cluster_location) > nr_clusters) ||
639	    (blkid_le64(ns->mft_mirror_cluster_location) > nr_clusters))
640		return 1;
641
642	off = blkid_le64(ns->mft_mirror_cluster_location) *
643		bytes_per_sector * sectors_per_cluster;
644
645	buf_mft = get_buffer(probe, off, mft_record_size);
646	if (!buf_mft)
647		return 1;
648
649	if (memcmp(buf_mft, "FILE", 4))
650		return 1;
651
652	off = blkid_le64(ns->mft_cluster_location) * bytes_per_sector *
653		sectors_per_cluster;
654
655	buf_mft = get_buffer(probe, off, mft_record_size);
656	if (!buf_mft)
657		return 1;
658
659	if (memcmp(buf_mft, "FILE", 4))
660		return 1;
661
662	off += MFT_RECORD_VOLUME * mft_record_size;
663
664	buf_mft = get_buffer(probe, off, mft_record_size);
665	if (!buf_mft)
666		return 1;
667
668	if (memcmp(buf_mft, "FILE", 4))
669		return 1;
670
671	mft = (struct master_file_table_record *) buf_mft;
672
673	attr_off = blkid_le16(mft->attrs_offset);
674	label_str[0] = 0;
675
676	while (1) {
677		attr = (struct file_attribute *) (buf_mft + attr_off);
678		attr_len = blkid_le16(attr->len);
679		attr_type = blkid_le32(attr->type);
680		val_off = blkid_le16(attr->value_offset);
681		val_len = blkid_le32(attr->value_len);
682
683		attr_off += attr_len;
684
685		if ((attr_off > mft_record_size) ||
686		    (attr_len == 0))
687			break;
688
689		if (attr_type == MFT_RECORD_ATTR_END)
690			break;
691
692		if (attr_type == MFT_RECORD_ATTR_VOLUME_NAME) {
693			if (val_len > sizeof(label_str))
694				val_len = sizeof(label_str)-1;
695
696			for (i=0, cp=label_str; i < val_len; i+=2,cp++) {
697				val = ((__u8 *) attr) + val_off + i;
698				*cp = val[0];
699				if (val[1])
700					*cp = '?';
701			}
702			*cp = 0;
703		}
704	}
705
706	sprintf(uuid_str, "%016llX", blkid_le64(ns->volume_serial));
707	blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
708	if (label_str[0])
709		blkid_set_tag(probe->dev, "LABEL", label_str, 0);
710	return 0;
711}
712
713
714static int probe_xfs(struct blkid_probe *probe,
715		     struct blkid_magic *id __BLKID_ATTR((unused)),
716		     unsigned char *buf)
717{
718	struct xfs_super_block *xs;
719	const char *label = 0;
720
721	xs = (struct xfs_super_block *)buf;
722
723	if (strlen(xs->xs_fname))
724		label = xs->xs_fname;
725	blkid_set_tag(probe->dev, "LABEL", label, sizeof(xs->xs_fname));
726	set_uuid(probe->dev, xs->xs_uuid, 0);
727	return 0;
728}
729
730static int probe_reiserfs(struct blkid_probe *probe,
731			  struct blkid_magic *id, unsigned char *buf)
732{
733	struct reiserfs_super_block *rs = (struct reiserfs_super_block *) buf;
734	unsigned int blocksize;
735	const char *label = 0;
736
737	blocksize = blkid_le16(rs->rs_blocksize);
738
739	/* The blocksize must be at least 1k */
740	if ((blocksize >> 10) == 0)
741		return -BLKID_ERR_PARAM;
742
743	/* If the superblock is inside the journal, we have the wrong one */
744	if (id->bim_kboff/(blocksize>>10) > blkid_le32(rs->rs_journal_block))
745		return -BLKID_ERR_BIG;
746
747	/* LABEL/UUID are only valid for later versions of Reiserfs v3.6. */
748	if (id->bim_magic[6] == '2' || id->bim_magic[6] == '3') {
749		if (strlen(rs->rs_label))
750			label = rs->rs_label;
751		set_uuid(probe->dev, rs->rs_uuid, 0);
752	}
753	blkid_set_tag(probe->dev, "LABEL", label, sizeof(rs->rs_label));
754
755	return 0;
756}
757
758static int probe_reiserfs4(struct blkid_probe *probe,
759			   struct blkid_magic *id __BLKID_ATTR((unused)),
760			   unsigned char *buf)
761{
762	struct reiser4_super_block *rs4 = (struct reiser4_super_block *) buf;
763	const unsigned char *label = 0;
764
765	if (strlen((char *) rs4->rs4_label))
766		label = rs4->rs4_label;
767	set_uuid(probe->dev, rs4->rs4_uuid, 0);
768	blkid_set_tag(probe->dev, "LABEL", (const char *) label,
769		      sizeof(rs4->rs4_label));
770
771	return 0;
772}
773
774static int probe_jfs(struct blkid_probe *probe,
775		     struct blkid_magic *id __BLKID_ATTR((unused)),
776		     unsigned char *buf)
777{
778	struct jfs_super_block *js;
779	const char *label = 0;
780
781	js = (struct jfs_super_block *)buf;
782
783	if (blkid_le32(js->js_bsize) != (1 << blkid_le16(js->js_l2bsize)))
784		return 1;
785
786	if (blkid_le32(js->js_pbsize) != (1 << blkid_le16(js->js_l2pbsize)))
787		return 1;
788
789	if ((blkid_le16(js->js_l2bsize) - blkid_le16(js->js_l2pbsize)) !=
790	    blkid_le16(js->js_l2bfactor))
791		return 1;
792
793	if (strlen((char *) js->js_label))
794		label = (char *) js->js_label;
795	blkid_set_tag(probe->dev, "LABEL", label, sizeof(js->js_label));
796	set_uuid(probe->dev, js->js_uuid, 0);
797	return 0;
798}
799
800static int probe_zfs(struct blkid_probe *probe, struct blkid_magic *id,
801		     unsigned char *buf)
802{
803#if 0
804	char *vdev_label;
805	const char *pool_name = 0;
806
807	/* read nvpair data for pool name, pool GUID (complex) */
808	blkid_set_tag(probe->dev, "LABEL", pool_name, sizeof(pool_name));
809	set_uuid(probe->dev, pool_guid, 0);
810#endif
811	return 0;
812}
813
814static int probe_luks(struct blkid_probe *probe,
815		       struct blkid_magic *id __BLKID_ATTR((unused)),
816		       unsigned char *buf)
817{
818	char uuid[40];
819
820	/* 168 is the offset to the 40 character uuid:
821	 * http://luks.endorphin.org/LUKS-on-disk-format.pdf */
822	strncpy(uuid, (char *) buf+168, 40);
823	blkid_set_tag(probe->dev, "UUID", uuid, sizeof(uuid));
824	return 0;
825}
826
827static int probe_romfs(struct blkid_probe *probe,
828		       struct blkid_magic *id __BLKID_ATTR((unused)),
829		       unsigned char *buf)
830{
831	struct romfs_super_block *ros;
832	const char *label = 0;
833
834	ros = (struct romfs_super_block *)buf;
835
836	if (strlen((char *) ros->ros_volume))
837		label = (char *) ros->ros_volume;
838	blkid_set_tag(probe->dev, "LABEL", label, 0);
839	return 0;
840}
841
842static int probe_cramfs(struct blkid_probe *probe,
843			struct blkid_magic *id __BLKID_ATTR((unused)),
844			unsigned char *buf)
845{
846	struct cramfs_super_block *csb;
847	const char *label = 0;
848
849	csb = (struct cramfs_super_block *)buf;
850
851	if (strlen((char *) csb->name))
852		label = (char *) csb->name;
853	blkid_set_tag(probe->dev, "LABEL", label, 0);
854	return 0;
855}
856
857static int probe_swap0(struct blkid_probe *probe,
858		       struct blkid_magic *id __BLKID_ATTR((unused)),
859		       unsigned char *buf __BLKID_ATTR((unused)))
860{
861	blkid_set_tag(probe->dev, "UUID", 0, 0);
862	blkid_set_tag(probe->dev, "LABEL", 0, 0);
863	return 0;
864}
865
866static int probe_swap1(struct blkid_probe *probe,
867		       struct blkid_magic *id,
868		       unsigned char *buf __BLKID_ATTR((unused)))
869{
870	struct swap_id_block *sws;
871
872	probe_swap0(probe, id, buf);
873	/*
874	 * Version 1 swap headers are always located at offset of 1024
875	 * bytes, although the swap signature itself is located at the
876	 * end of the page (which may vary depending on hardware
877	 * pagesize).
878	 */
879	sws = (struct swap_id_block *) get_buffer(probe, 1024, 1024);
880	if (!sws)
881		return 1;
882
883	/* check for wrong version or zeroed pagecount, for sanity */
884	if (!memcmp(id->bim_magic, "SWAPSPACE2", id->bim_len) &&
885			(sws->sws_version != 1 || sws->sws_lastpage == 0))
886		return 1;
887
888	/* arbitrary sanity check.. is there any garbage down there? */
889	if (sws->sws_pad[32] == 0 && sws->sws_pad[33] == 0)  {
890		if (sws->sws_volume[0])
891			blkid_set_tag(probe->dev, "LABEL", sws->sws_volume,
892				      sizeof(sws->sws_volume));
893		if (sws->sws_uuid[0])
894			set_uuid(probe->dev, sws->sws_uuid, 0);
895	}
896	return 0;
897}
898
899static int probe_iso9660(struct blkid_probe *probe,
900			 struct blkid_magic *id __BLKID_ATTR((unused)),
901			 unsigned char *buf)
902{
903	struct iso_volume_descriptor *iso;
904	const unsigned char *label;
905
906	iso = (struct iso_volume_descriptor *) buf;
907	label = iso->volume_id;
908
909	blkid_set_tag(probe->dev, "LABEL", (const char *) label,
910		      figure_label_len(label, 32));
911	return 0;
912}
913
914
915static const char
916*udf_magic[] = { "BEA01", "BOOT2", "CD001", "CDW02", "NSR02",
917		 "NSR03", "TEA01", 0 };
918
919static int probe_udf(struct blkid_probe *probe,
920		     struct blkid_magic *id __BLKID_ATTR((unused)),
921		     unsigned char *buf __BLKID_ATTR((unused)))
922{
923	int j, bs;
924	struct iso_volume_descriptor *isosb;
925	const char ** m;
926
927	/* determine the block size by scanning in 2K increments
928	   (block sizes larger than 2K will be null padded) */
929	for (bs = 1; bs < 16; bs++) {
930		isosb = (struct iso_volume_descriptor *)
931			get_buffer(probe, bs*2048+32768, sizeof(isosb));
932		if (!isosb)
933			return 1;
934		if (isosb->vd_id[0])
935			break;
936	}
937
938	/* Scan up to another 64 blocks looking for additional VSD's */
939	for (j = 1; j < 64; j++) {
940		if (j > 1) {
941			isosb = (struct iso_volume_descriptor *)
942				get_buffer(probe, j*bs*2048+32768,
943					   sizeof(isosb));
944			if (!isosb)
945				return 1;
946		}
947		/* If we find NSR0x then call it udf:
948		   NSR01 for UDF 1.00
949		   NSR02 for UDF 1.50
950		   NSR03 for UDF 2.00 */
951		if (!memcmp(isosb->vd_id, "NSR0", 4))
952			return probe_iso9660(probe, id, buf);
953		for (m = udf_magic; *m; m++)
954			if (!memcmp(*m, isosb->vd_id, 5))
955				break;
956		if (*m == 0)
957			return 1;
958	}
959	return 1;
960}
961
962static int probe_ocfs(struct blkid_probe *probe,
963		      struct blkid_magic *id __BLKID_ATTR((unused)),
964		      unsigned char *buf)
965{
966	struct ocfs_volume_header ovh;
967	struct ocfs_volume_label ovl;
968	__u32 major;
969
970	memcpy(&ovh, buf, sizeof(ovh));
971	memcpy(&ovl, buf+512, sizeof(ovl));
972
973	major = ocfsmajor(ovh);
974	if (major == 1)
975		blkid_set_tag(probe->dev,"SEC_TYPE","ocfs1",sizeof("ocfs1"));
976	else if (major >= 9)
977		blkid_set_tag(probe->dev,"SEC_TYPE","ntocfs",sizeof("ntocfs"));
978
979	blkid_set_tag(probe->dev, "LABEL", ovl.label, ocfslabellen(ovl));
980	blkid_set_tag(probe->dev, "MOUNT", ovh.mount, ocfsmountlen(ovh));
981	set_uuid(probe->dev, ovl.vol_id, 0);
982	return 0;
983}
984
985static int probe_ocfs2(struct blkid_probe *probe,
986		       struct blkid_magic *id __BLKID_ATTR((unused)),
987		       unsigned char *buf)
988{
989	struct ocfs2_super_block *osb;
990
991	osb = (struct ocfs2_super_block *)buf;
992
993	blkid_set_tag(probe->dev, "LABEL", osb->s_label, sizeof(osb->s_label));
994	set_uuid(probe->dev, osb->s_uuid, 0);
995	return 0;
996}
997
998static int probe_oracleasm(struct blkid_probe *probe,
999			   struct blkid_magic *id __BLKID_ATTR((unused)),
1000			   unsigned char *buf)
1001{
1002	struct oracle_asm_disk_label *dl;
1003
1004	dl = (struct oracle_asm_disk_label *)buf;
1005
1006	blkid_set_tag(probe->dev, "LABEL", dl->dl_id, sizeof(dl->dl_id));
1007	return 0;
1008}
1009
1010static int probe_gfs(struct blkid_probe *probe,
1011		     struct blkid_magic *id __BLKID_ATTR((unused)),
1012		     unsigned char *buf)
1013{
1014	struct gfs2_sb *sbd;
1015	const char *label = 0;
1016
1017	sbd = (struct gfs2_sb *)buf;
1018
1019	if (blkid_be32(sbd->sb_fs_format) == GFS_FORMAT_FS &&
1020	    blkid_be32(sbd->sb_multihost_format) == GFS_FORMAT_MULTI)
1021	{
1022		blkid_set_tag(probe->dev, "UUID", 0, 0);
1023
1024		if (strlen(sbd->sb_locktable))
1025			label = sbd->sb_locktable;
1026		blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
1027		return 0;
1028	}
1029	return 1;
1030}
1031
1032static int probe_gfs2(struct blkid_probe *probe,
1033		     struct blkid_magic *id __BLKID_ATTR((unused)),
1034		     unsigned char *buf)
1035{
1036	struct gfs2_sb *sbd;
1037	const char *label = 0;
1038
1039	sbd = (struct gfs2_sb *)buf;
1040
1041	if (blkid_be32(sbd->sb_fs_format) == GFS2_FORMAT_FS &&
1042	    blkid_be32(sbd->sb_multihost_format) == GFS2_FORMAT_MULTI)
1043	{
1044		blkid_set_tag(probe->dev, "UUID", 0, 0);
1045
1046		if (strlen(sbd->sb_locktable))
1047			label = sbd->sb_locktable;
1048		blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
1049		return 0;
1050	}
1051	return 1;
1052}
1053
1054void unicode_16be_to_utf8(unsigned char *str, int out_len,
1055			 const unsigned char *buf, int in_len)
1056{
1057	int i, j;
1058	unsigned int c;
1059
1060	for (i = j = 0; i + 2 <= in_len; i += 2) {
1061		c = (buf[i] << 8) | buf[i+1];
1062		if (c == 0) {
1063			str[j] = '\0';
1064			break;
1065		} else if (c < 0x80) {
1066			if (j+1 >= out_len)
1067				break;
1068			str[j++] = (unsigned char) c;
1069		} else if (c < 0x800) {
1070			if (j+2 >= out_len)
1071				break;
1072			str[j++] = (unsigned char) (0xc0 | (c >> 6));
1073			str[j++] = (unsigned char) (0x80 | (c & 0x3f));
1074		} else {
1075			if (j+3 >= out_len)
1076				break;
1077			str[j++] = (unsigned char) (0xe0 | (c >> 12));
1078			str[j++] = (unsigned char) (0x80 | ((c >> 6) & 0x3f));
1079			str[j++] = (unsigned char) (0x80 | (c & 0x3f));
1080		}
1081	}
1082	str[j] = '\0';
1083}
1084
1085static int probe_hfs(struct blkid_probe *probe __BLKID_ATTR((unused)),
1086			 struct blkid_magic *id __BLKID_ATTR((unused)),
1087			 unsigned char *buf)
1088{
1089	struct hfs_mdb *hfs = (struct hfs_mdb *) buf;
1090	char	uuid_str[17];
1091	__u64	uuid;
1092
1093	if ((memcmp(hfs->embed_sig, "H+", 2) == 0) ||
1094	    (memcmp(hfs->embed_sig, "HX", 2) == 0))
1095		return 1;	/* Not hfs, but an embedded HFS+ */
1096
1097	uuid = blkid_le64(*((unsigned long long *) hfs->finder_info.id));
1098	if (uuid) {
1099		sprintf(uuid_str, "%016llX", uuid);
1100		blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
1101	}
1102	blkid_set_tag(probe->dev, "LABEL", hfs->label, hfs->label_len);
1103	return 0;
1104}
1105
1106
1107static int probe_hfsplus(struct blkid_probe *probe,
1108			 struct blkid_magic *id,
1109			 unsigned char *buf)
1110{
1111	struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
1112	struct hfsplus_bnode_descriptor *descr;
1113	struct hfsplus_bheader_record *bnode;
1114	struct hfsplus_catalog_key *key;
1115	struct hfsplus_vol_header *hfsplus;
1116	struct hfs_mdb *sbd = (struct hfs_mdb *) buf;
1117	unsigned int alloc_block_size;
1118	unsigned int alloc_first_block;
1119	unsigned int embed_first_block;
1120	unsigned int off = 0;
1121	unsigned int blocksize;
1122	unsigned int cat_block;
1123	unsigned int ext_block_start;
1124	unsigned int ext_block_count;
1125	unsigned int record_count;
1126	unsigned int leaf_node_head;
1127	unsigned int leaf_node_count;
1128	unsigned int leaf_node_size;
1129	unsigned int leaf_block;
1130	unsigned int label_len;
1131	int ext;
1132	__u64 leaf_off, uuid;
1133	char	uuid_str[17], label[512];
1134
1135	/* Check for a HFS+ volume embedded in a HFS volume */
1136	if (memcmp(sbd->signature, "BD", 2) == 0) {
1137		if ((memcmp(sbd->embed_sig, "H+", 2) != 0) &&
1138		    (memcmp(sbd->embed_sig, "HX", 2) != 0))
1139			/* This must be an HFS volume, so fail */
1140			return 1;
1141
1142		alloc_block_size = blkid_be32(sbd->al_blk_size);
1143		alloc_first_block = blkid_be16(sbd->al_bl_st);
1144		embed_first_block = blkid_be16(sbd->embed_startblock);
1145		off = (alloc_first_block * 512) +
1146			(embed_first_block * alloc_block_size);
1147		buf = get_buffer(probe, off + (id->bim_kboff * 1024),
1148				 sizeof(sbd));
1149		if (!buf)
1150			return 1;
1151
1152		hfsplus = (struct hfsplus_vol_header *) buf;
1153	}
1154
1155	hfsplus = (struct hfsplus_vol_header *) buf;
1156
1157	if ((memcmp(hfsplus->signature, "H+", 2) != 0) &&
1158	    (memcmp(hfsplus->signature, "HX", 2) != 0))
1159		return 1;
1160
1161	uuid = blkid_le64(*((unsigned long long *) hfsplus->finder_info.id));
1162	if (uuid) {
1163		sprintf(uuid_str, "%016llX", uuid);
1164		blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
1165	}
1166
1167	blocksize = blkid_be32(hfsplus->blocksize);
1168	memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
1169	cat_block = blkid_be32(extents[0].start_block);
1170
1171	buf = get_buffer(probe, off + (cat_block * blocksize), 0x2000);
1172	if (!buf)
1173		return 0;
1174
1175	bnode = (struct hfsplus_bheader_record *)
1176		&buf[sizeof(struct hfsplus_bnode_descriptor)];
1177
1178	leaf_node_head = blkid_be32(bnode->leaf_head);
1179	leaf_node_size = blkid_be16(bnode->node_size);
1180	leaf_node_count = blkid_be32(bnode->leaf_count);
1181	if (leaf_node_count == 0)
1182		return 0;
1183
1184	leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
1185
1186	/* get physical location */
1187	for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
1188		ext_block_start = blkid_be32(extents[ext].start_block);
1189		ext_block_count = blkid_be32(extents[ext].block_count);
1190		if (ext_block_count == 0)
1191			return 0;
1192
1193		/* this is our extent */
1194		if (leaf_block < ext_block_count)
1195			break;
1196
1197		leaf_block -= ext_block_count;
1198	}
1199	if (ext == HFSPLUS_EXTENT_COUNT)
1200		return 0;
1201
1202	leaf_off = (ext_block_start + leaf_block) * blocksize;
1203
1204	buf = get_buffer(probe, off + leaf_off, leaf_node_size);
1205	if (!buf)
1206		return 0;
1207
1208	descr = (struct hfsplus_bnode_descriptor *) buf;
1209	record_count = blkid_be16(descr->num_recs);
1210	if (record_count == 0)
1211		return 0;
1212
1213	if (descr->type != HFS_NODE_LEAF)
1214		return 0;
1215
1216	key = (struct hfsplus_catalog_key *)
1217		&buf[sizeof(struct hfsplus_bnode_descriptor)];
1218
1219	if (blkid_be32(key->parent_id) != HFSPLUS_POR_CNID)
1220		return 0;
1221
1222	label_len = blkid_be16(key->unicode_len) * 2;
1223	unicode_16be_to_utf8(label, sizeof(label), key->unicode, label_len);
1224	blkid_set_tag(probe->dev, "LABEL", label, 0);
1225	return 0;
1226}
1227
1228#define LVM2_LABEL_SIZE 512
1229static unsigned int lvm2_calc_crc(const void *buf, unsigned int size)
1230{
1231	static const unsigned int crctab[] = {
1232		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1233		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1234		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1235		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1236	};
1237	unsigned int i, crc = 0xf597a6cf;
1238	const __u8 *data = (const __u8 *) buf;
1239
1240	for (i = 0; i < size; i++) {
1241		crc ^= *data++;
1242		crc = (crc >> 4) ^ crctab[crc & 0xf];
1243		crc = (crc >> 4) ^ crctab[crc & 0xf];
1244	}
1245	return crc;
1246}
1247
1248static int probe_lvm2(struct blkid_probe *probe,
1249			struct blkid_magic *id,
1250			unsigned char *buf)
1251{
1252	int sector = (id->bim_kboff) << 1;
1253	struct lvm2_pv_label_header *label= (struct lvm2_pv_label_header *)buf;
1254	char *p, *q, uuid[40];
1255	unsigned int i, b;
1256
1257	/* buf is at 0k or 1k offset; find label inside */
1258	if (memcmp(buf, "LABELONE", 8) == 0) {
1259		label = (struct lvm2_pv_label_header *)buf;
1260	} else if (memcmp(buf + 512, "LABELONE", 8) == 0) {
1261		label = (struct lvm2_pv_label_header *)(buf + 512);
1262		sector++;
1263	} else {
1264		return 1;
1265	}
1266
1267	if (blkid_le64(label->sector_xl) != (unsigned) sector) {
1268		DBG(DEBUG_PROBE,
1269		    printf("LVM2: label for sector %llu found at sector %d\n",
1270			   blkid_le64(label->sector_xl), sector));
1271		return 1;
1272	}
1273
1274	if (lvm2_calc_crc(&label->offset_xl, LVM2_LABEL_SIZE -
1275			  ((char *)&label->offset_xl - (char *)label)) !=
1276			blkid_le32(label->crc_xl)) {
1277		DBG(DEBUG_PROBE,
1278		    printf("LVM2: label checksum incorrect at sector %d\n",
1279			   sector));
1280		return 1;
1281	}
1282
1283	for (i=0, b=1, p=uuid, q= (char *) label->pv_uuid; i <= 32;
1284	     i++, b <<= 1) {
1285		if (b & 0x4444440)
1286			*p++ = '-';
1287		*p++ = *q++;
1288	}
1289
1290	blkid_set_tag(probe->dev, "UUID", uuid, LVM2_ID_LEN+6);
1291
1292	return 0;
1293}
1294/*
1295 * Various filesystem magics that we can check for.  Note that kboff and
1296 * sboff are in kilobytes and bytes respectively.  All magics are in
1297 * byte strings so we don't worry about endian issues.
1298 */
1299static struct blkid_magic type_array[] = {
1300/*  type     kboff   sboff len  magic			probe */
1301  { "oracleasm", 0,	32,  8, "ORCLDISK",		probe_oracleasm },
1302  { "ntfs",	 0,	 3,  8, "NTFS    ",		probe_ntfs },
1303  { "jbd",	 1,   0x38,  2, "\123\357",		probe_jbd },
1304  { "ext4dev",	 1,   0x38,  2, "\123\357",		probe_ext4dev },
1305  { "ext4",	 1,   0x38,  2, "\123\357",		probe_ext4 },
1306  { "ext3",	 1,   0x38,  2, "\123\357",		probe_ext3 },
1307  { "ext2",	 1,   0x38,  2, "\123\357",		probe_ext2 },
1308  { "reiserfs",	 8,   0x34,  8, "ReIsErFs",		probe_reiserfs },
1309  { "reiserfs", 64,   0x34,  9, "ReIsEr2Fs",		probe_reiserfs },
1310  { "reiserfs", 64,   0x34,  9, "ReIsEr3Fs",		probe_reiserfs },
1311  { "reiserfs", 64,   0x34,  8, "ReIsErFs",		probe_reiserfs },
1312  { "reiserfs",	 8,	20,  8, "ReIsErFs",		probe_reiserfs },
1313  { "reiser4",  64,	 0,  7, "ReIsEr4",		probe_reiserfs4 },
1314  { "gfs2",     64,      0,  4, "\x01\x16\x19\x70",     probe_gfs2 },
1315  { "gfs",      64,      0,  4, "\x01\x16\x19\x70",     probe_gfs },
1316  { "vfat",      0,   0x52,  5, "MSWIN",                probe_fat },
1317  { "vfat",      0,   0x52,  8, "FAT32   ",             probe_fat },
1318  { "vfat",      0,   0x36,  5, "MSDOS",                probe_fat },
1319  { "vfat",      0,   0x36,  8, "FAT16   ",             probe_fat },
1320  { "vfat",      0,   0x36,  8, "FAT12   ",             probe_fat },
1321  { "vfat",      0,      0,  1, "\353",                 probe_fat_nomagic },
1322  { "vfat",      0,      0,  1, "\351",                 probe_fat_nomagic },
1323  { "vfat",      0,  0x1fe,  2, "\125\252",             probe_fat_nomagic },
1324  { "minix",     1,   0x10,  2, "\177\023",             0 },
1325  { "minix",     1,   0x10,  2, "\217\023",             0 },
1326  { "minix",	 1,   0x10,  2, "\150\044",		0 },
1327  { "minix",	 1,   0x10,  2, "\170\044",		0 },
1328  { "vxfs",	 1,	 0,  4, "\365\374\001\245",	0 },
1329  { "xfs",	 0,	 0,  4, "XFSB",			probe_xfs },
1330  { "romfs",	 0,	 0,  8, "-rom1fs-",		probe_romfs },
1331  { "bfs",	 0,	 0,  4, "\316\372\173\033",	0 },
1332  { "cramfs",	 0,	 0,  4, "E=\315\050",		probe_cramfs },
1333  { "qnx4",	 0,	 4,  6, "QNX4FS",		0 },
1334  { "udf",	32,	 1,  5, "BEA01",		probe_udf },
1335  { "udf",	32,	 1,  5, "BOOT2",		probe_udf },
1336  { "udf",	32,	 1,  5, "CD001",		probe_udf },
1337  { "udf",	32,	 1,  5, "CDW02",		probe_udf },
1338  { "udf",	32,	 1,  5, "NSR02",		probe_udf },
1339  { "udf",	32,	 1,  5, "NSR03",		probe_udf },
1340  { "udf",	32,	 1,  5, "TEA01",		probe_udf },
1341  { "iso9660",	32,	 1,  5, "CD001",		probe_iso9660 },
1342  { "iso9660",	32,	 9,  5, "CDROM",		probe_iso9660 },
1343  { "jfs",	32,	 0,  4, "JFS1",			probe_jfs },
1344  { "zfs",       8,	 0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
1345  { "zfs",       8,	 0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
1346  { "zfs",     264,	 0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
1347  { "zfs",     264,	 0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
1348  { "hfsplus",	 1,	 0,  2, "BD",			probe_hfsplus },
1349  { "hfsplus",	 1,	 0,  2, "H+",			probe_hfsplus },
1350  { "hfsplus",	 1,	 0,  2, "HX",			probe_hfsplus },
1351  { "hfs",	 1,	 0,  2, "BD",			probe_hfs },
1352  { "ufs",	 8,  0x55c,  4, "T\031\001\000",	0 },
1353  { "hpfs",	 8,	 0,  4, "I\350\225\371",	0 },
1354  { "sysv",	 0,  0x3f8,  4, "\020~\030\375",	0 },
1355  { "swap",	 0,  0xff6, 10, "SWAP-SPACE",		probe_swap0 },
1356  { "swap",	 0,  0xff6, 10, "SWAPSPACE2",		probe_swap1 },
1357  { "swsuspend", 0,  0xff6,  9, "S1SUSPEND",		probe_swap1 },
1358  { "swsuspend", 0,  0xff6,  9, "S2SUSPEND",		probe_swap1 },
1359  { "swap",	 0, 0x1ff6, 10, "SWAP-SPACE",		probe_swap0 },
1360  { "swap",	 0, 0x1ff6, 10, "SWAPSPACE2",		probe_swap1 },
1361  { "swsuspend", 0, 0x1ff6,  9, "S1SUSPEND",		probe_swap1 },
1362  { "swsuspend", 0, 0x1ff6,  9, "S2SUSPEND",		probe_swap1 },
1363  { "swap",	 0, 0x3ff6, 10, "SWAP-SPACE",		probe_swap0 },
1364  { "swap",	 0, 0x3ff6, 10, "SWAPSPACE2",		probe_swap1 },
1365  { "swsuspend", 0, 0x3ff6,  9, "S1SUSPEND",		probe_swap1 },
1366  { "swsuspend", 0, 0x3ff6,  9, "S2SUSPEND",		probe_swap1 },
1367  { "swap",	 0, 0x7ff6, 10, "SWAP-SPACE",		probe_swap0 },
1368  { "swap",	 0, 0x7ff6, 10, "SWAPSPACE2",		probe_swap1 },
1369  { "swsuspend", 0, 0x7ff6,  9, "S1SUSPEND",		probe_swap1 },
1370  { "swsuspend", 0, 0x7ff6,  9, "S2SUSPEND",		probe_swap1 },
1371  { "swap",	 0, 0xfff6, 10, "SWAP-SPACE",		probe_swap0 },
1372  { "swap",	 0, 0xfff6, 10, "SWAPSPACE2",		probe_swap1 },
1373  { "swsuspend", 0, 0xfff6,  9, "S1SUSPEND",		probe_swap1 },
1374  { "swsuspend", 0, 0xfff6,  9, "S2SUSPEND",		probe_swap1 },
1375  { "ocfs",	 0,	 8,  9,	"OracleCFS",		probe_ocfs },
1376  { "ocfs2",	 1,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1377  { "ocfs2",	 2,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1378  { "ocfs2",	 4,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1379  { "ocfs2",	 8,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1380  { "crypt_LUKS", 0,	 0,  6,	"LUKS\xba\xbe",		probe_luks },
1381  { "squashfs",	 0,	 0,  4,	"sqsh",			0 },
1382  { "squashfs",	 0,	 0,  4,	"hsqs",			0 },
1383  { "lvm2pv",	 0,  0x218,  8, "LVM2 001",		probe_lvm2 },
1384  { "lvm2pv",	 0,  0x018,  8, "LVM2 001",		probe_lvm2 },
1385  { "lvm2pv",	 1,  0x018,  8, "LVM2 001",		probe_lvm2 },
1386  { "lvm2pv",	 1,  0x218,  8, "LVM2 001",		probe_lvm2 },
1387  {   NULL,	 0,	 0,  0, NULL,			NULL }
1388};
1389
1390/*
1391 * Verify that the data in dev is consistent with what is on the actual
1392 * block device (using the devname field only).  Normally this will be
1393 * called when finding items in the cache, but for long running processes
1394 * is also desirable to revalidate an item before use.
1395 *
1396 * If we are unable to revalidate the data, we return the old data and
1397 * do not set the BLKID_BID_FL_VERIFIED flag on it.
1398 */
1399blkid_dev blkid_verify(blkid_cache cache, blkid_dev dev)
1400{
1401	struct blkid_magic *id;
1402	struct blkid_probe probe;
1403	blkid_tag_iterate iter;
1404	unsigned char *buf;
1405	const char *type, *value;
1406	struct stat st;
1407	time_t diff, now;
1408	int idx;
1409
1410	if (!dev)
1411		return NULL;
1412
1413	now = time(0);
1414	diff = now - dev->bid_time;
1415
1416	if (stat(dev->bid_name, &st) < 0) {
1417		DBG(DEBUG_PROBE,
1418		    printf("blkid_verify: error %s (%d) while "
1419			   "trying to stat %s\n", strerror(errno), errno,
1420			   dev->bid_name));
1421	open_err:
1422		if ((errno == EPERM) || (errno == EACCES) || (errno == ENOENT)) {
1423			/* We don't have read permission, just return cache data. */
1424			DBG(DEBUG_PROBE, printf("returning unverified data for %s\n",
1425						dev->bid_name));
1426			return dev;
1427		}
1428		blkid_free_dev(dev);
1429		return NULL;
1430	}
1431
1432	if ((now >= dev->bid_time) &&
1433	    (st.st_mtime <= dev->bid_time) &&
1434	    ((diff < BLKID_PROBE_MIN) ||
1435	     (dev->bid_flags & BLKID_BID_FL_VERIFIED &&
1436	      diff < BLKID_PROBE_INTERVAL)))
1437		return dev;
1438
1439	DBG(DEBUG_PROBE,
1440	    printf("need to revalidate %s (cache time %lu, stat time %lu,\n\t"
1441		   "time since last check %lu)\n",
1442		   dev->bid_name, (unsigned long)dev->bid_time,
1443		   (unsigned long)st.st_mtime, (unsigned long)diff));
1444
1445	if ((probe.fd = open(dev->bid_name, O_RDONLY)) < 0) {
1446		DBG(DEBUG_PROBE, printf("blkid_verify: error %s (%d) while "
1447					"opening %s\n", strerror(errno), errno,
1448					dev->bid_name));
1449		goto open_err;
1450	}
1451
1452	probe.cache = cache;
1453	probe.dev = dev;
1454	probe.sbbuf = 0;
1455	probe.buf = 0;
1456	probe.buf_max = 0;
1457
1458	/*
1459	 * Iterate over the type array.  If we already know the type,
1460	 * then try that first.  If it doesn't work, then blow away
1461	 * the type information, and try again.
1462	 *
1463	 */
1464try_again:
1465	type = 0;
1466	if (!dev->bid_type || !strcmp(dev->bid_type, "mdraid")) {
1467		uuid_t	uuid;
1468
1469		if (check_mdraid(probe.fd, uuid) == 0) {
1470			set_uuid(dev, uuid, 0);
1471			type = "mdraid";
1472			goto found_type;
1473		}
1474	}
1475	for (id = type_array; id->bim_type; id++) {
1476		if (dev->bid_type &&
1477		    strcmp(id->bim_type, dev->bid_type))
1478			continue;
1479
1480		idx = id->bim_kboff + (id->bim_sboff >> 10);
1481		buf = get_buffer(&probe, idx << 10, 1024);
1482		if (!buf)
1483			continue;
1484
1485		if (memcmp(id->bim_magic, buf + (id->bim_sboff & 0x3ff),
1486			   id->bim_len))
1487			continue;
1488
1489		if ((id->bim_probe == NULL) ||
1490		    (id->bim_probe(&probe, id, buf) == 0)) {
1491			type = id->bim_type;
1492			goto found_type;
1493		}
1494	}
1495
1496	if (!id->bim_type && dev->bid_type) {
1497		/*
1498		 * Zap the device filesystem information and try again
1499		 */
1500		DBG(DEBUG_PROBE,
1501		    printf("previous fs type %s not valid, "
1502			   "trying full probe\n", dev->bid_type));
1503		iter = blkid_tag_iterate_begin(dev);
1504		while (blkid_tag_next(iter, &type, &value) == 0)
1505			blkid_set_tag(dev, type, 0, 0);
1506		blkid_tag_iterate_end(iter);
1507		goto try_again;
1508	}
1509
1510	if (!dev->bid_type) {
1511		blkid_free_dev(dev);
1512		dev = 0;
1513		goto found_type;
1514	}
1515
1516found_type:
1517	if (dev && type) {
1518		dev->bid_devno = st.st_rdev;
1519		dev->bid_time = time(0);
1520		dev->bid_flags |= BLKID_BID_FL_VERIFIED;
1521		cache->bic_flags |= BLKID_BIC_FL_CHANGED;
1522
1523		blkid_set_tag(dev, "TYPE", type, 0);
1524
1525		DBG(DEBUG_PROBE, printf("%s: devno 0x%04llx, type %s\n",
1526			   dev->bid_name, (long long)st.st_rdev, type));
1527	}
1528
1529	if (probe.sbbuf)
1530		free(probe.sbbuf);
1531	if (probe.buf)
1532		free(probe.buf);
1533	if (probe.fd >= 0)
1534		close(probe.fd);
1535
1536	return dev;
1537}
1538
1539int blkid_known_fstype(const char *fstype)
1540{
1541	struct blkid_magic *id;
1542
1543	for (id = type_array; id->bim_type; id++) {
1544		if (strcmp(fstype, id->bim_type) == 0)
1545			return 1;
1546	}
1547	return 0;
1548}
1549
1550#ifdef TEST_PROGRAM
1551int main(int argc, char **argv)
1552{
1553	blkid_dev dev;
1554	blkid_cache cache;
1555	int ret;
1556
1557	if (argc != 2) {
1558		fprintf(stderr, "Usage: %s device\n"
1559			"Probe a single device to determine type\n", argv[0]);
1560		exit(1);
1561	}
1562	if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
1563		fprintf(stderr, "%s: error creating cache (%d)\n",
1564			argv[0], ret);
1565		exit(1);
1566	}
1567	dev = blkid_get_dev(cache, argv[1], BLKID_DEV_NORMAL);
1568	if (!dev) {
1569		printf("%s: %s has an unsupported type\n", argv[0], argv[1]);
1570		return (1);
1571	}
1572	printf("TYPE='%s'\n", dev->bid_type ? dev->bid_type : "(null)");
1573	if (dev->bid_label)
1574		printf("LABEL='%s'\n", dev->bid_label);
1575	if (dev->bid_uuid)
1576		printf("UUID='%s'\n", dev->bid_uuid);
1577
1578	blkid_free_dev(dev);
1579	return (0);
1580}
1581#endif
1582