probe.c revision e0ed7404719a9ddd2ba427a80db5365c8bad18c0
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#ifdef __linux__
30#include <sys/utsname.h>
31#endif
32#ifdef HAVE_ERRNO_H
33#include <errno.h>
34#endif
35#include "blkidP.h"
36#include "uuid/uuid.h"
37#include "probe.h"
38
39static int figure_label_len(const unsigned char *label, int len)
40{
41	const unsigned char *end = label + len - 1;
42
43	while ((*end == ' ' || *end == 0) && end >= label)
44		--end;
45	if (end >= label)
46		return end - label + 1;
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#ifdef __linux__
207	struct utsname	uts;
208	FILE		*f;
209	char		buf[1024], *cp;
210	int		namesz;
211
212	if (uname(&uts))
213		return (0);
214	snprintf(buf, sizeof(buf), "/lib/modules/%s/modules.dep", uts.release);
215
216	f = fopen(buf, "r");
217	if (!f)
218		return (0);
219
220	namesz = strlen(fs_name);
221
222	while (!feof(f)) {
223		if (!fgets(buf, sizeof(buf), f))
224			break;
225		if ((cp = strchr(buf, ':')) != NULL)
226			*cp = 0;
227		else
228			continue;
229		if ((cp = strrchr(buf, '/')) != NULL)
230			cp++;
231		else
232			cp = buf;
233		if (!strncmp(cp, fs_name, namesz) &&
234		    (!strcmp(cp + namesz, ".ko") ||
235		     !strcmp(cp + namesz, ".ko.gz"))) {
236			fclose(f);
237			return (1);
238		}
239	}
240	fclose(f);
241#endif
242	return (0);
243}
244
245static int linux_version_code()
246{
247#ifdef __linux__
248	struct utsname	ut;
249	static int	version_code = -1;
250	int		major, minor, rev;
251	char		*endptr;
252	const char 	*cp;
253
254	if (version_code > 0)
255		return version_code;
256
257	if (uname(&ut))
258		return 0;
259	cp = ut.release;
260
261	major = strtol(cp, &endptr, 10);
262	if (cp == endptr || *endptr != '.')
263		return 0;
264	cp = endptr + 1;
265	minor = strtol(cp, &endptr, 10);
266	if (cp == endptr || *endptr != '.')
267		return 0;
268	cp = endptr + 1;
269	rev = strtol(cp, &endptr, 10);
270	if (cp == endptr)
271		return 0;
272	version_code = (((major * 256) + minor) * 256) + rev;
273	return version_code;
274#else
275	return 0;
276#endif
277}
278
279#define EXT4_SUPPORTS_EXT2 (2 * 65536 + 6*256 + 29)
280
281static int system_supports_ext2(void)
282{
283	static time_t	last_check = 0;
284	static int	ret = -1;
285	time_t		now = time(0);
286
287	if (ret != -1 || (now - last_check) < 5)
288		return ret;
289	last_check = now;
290	ret = (fs_proc_check("ext2") || check_for_modules("ext2"));
291	return ret;
292}
293
294static int system_supports_ext4(void)
295{
296	static time_t	last_check = 0;
297	static int	ret = -1;
298	time_t		now = time(0);
299
300	if (ret != -1 || (now - last_check) < 5)
301		return ret;
302	last_check = now;
303	ret = (fs_proc_check("ext4") || check_for_modules("ext4"));
304	return ret;
305}
306
307static int system_supports_ext4dev(void)
308{
309	static time_t	last_check = 0;
310	static int	ret = -1;
311	time_t		now = time(0);
312
313	if (ret != -1 || (now - last_check) < 5)
314		return ret;
315	last_check = now;
316	ret = (fs_proc_check("ext4dev") || check_for_modules("ext4dev"));
317	return ret;
318}
319
320static int probe_ext4dev(struct blkid_probe *probe,
321			 struct blkid_magic *id,
322			 unsigned char *buf)
323{
324	struct ext2_super_block *es;
325	es = (struct ext2_super_block *)buf;
326
327	/* Distinguish from jbd */
328	if (blkid_le32(es->s_feature_incompat) &
329	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
330		return -BLKID_ERR_PARAM;
331
332	/*
333	 * If the filesystem does not have a journal and ext2 and ext4
334	 * is not present, then force this to be detected as an
335	 * ext4dev filesystem.
336	 */
337	if (!(blkid_le32(es->s_feature_compat) &
338	      EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
339	    !system_supports_ext2() && !system_supports_ext4() &&
340	    system_supports_ext4dev() &&
341	    linux_version_code() >= EXT4_SUPPORTS_EXT2)
342		goto force_ext4dev;
343
344	/*
345	 * If the filesystem is marked as OK for use by in-development
346	 * filesystem code, but ext4dev is not supported, and ext4 is,
347	 * then don't call ourselves ext4dev, since we should be
348	 * detected as ext4 in that case.
349	 *
350	 * If the filesystem is marked as in use by production
351	 * filesystem, then it can only be used by ext4 and NOT by
352	 * ext4dev, so always disclaim we are ext4dev in that case.
353	 */
354	if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS) {
355		if (!system_supports_ext4dev() && system_supports_ext4())
356			return -BLKID_ERR_PARAM;
357	} else
358		return -BLKID_ERR_PARAM;
359
360force_ext4dev:
361    	get_ext2_info(probe->dev, id, buf);
362	return 0;
363}
364
365static int probe_ext4(struct blkid_probe *probe, struct blkid_magic *id,
366		      unsigned char *buf)
367{
368	struct ext2_super_block *es;
369	es = (struct ext2_super_block *)buf;
370
371	/* Distinguish from jbd */
372	if (blkid_le32(es->s_feature_incompat) &
373	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
374		return -BLKID_ERR_PARAM;
375
376	/*
377	 * If the filesystem does not have a journal and ext2 is not
378	 * present, then force this to be detected as an ext2
379	 * filesystem.
380	 */
381	if (!(blkid_le32(es->s_feature_compat) &
382	      EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
383	    !system_supports_ext2() && system_supports_ext4() &&
384	    linux_version_code() >= EXT4_SUPPORTS_EXT2)
385		goto force_ext4;
386
387	/* Ext4 has at least one feature which ext3 doesn't understand */
388	if (!(blkid_le32(es->s_feature_ro_compat) &
389	      EXT3_FEATURE_RO_COMPAT_UNSUPPORTED) &&
390	    !(blkid_le32(es->s_feature_incompat) &
391	      EXT3_FEATURE_INCOMPAT_UNSUPPORTED))
392		return -BLKID_ERR_PARAM;
393
394force_ext4:
395	/*
396	 * If the filesystem is a OK for use by in-development
397	 * filesystem code, and ext4dev is supported or ext4 is not
398	 * supported, then don't call ourselves ext4, so we can redo
399	 * the detection and mark the filesystem as ext4dev.
400	 *
401	 * If the filesystem is marked as in use by production
402	 * filesystem, then it can only be used by ext4 and NOT by
403	 * ext4dev.
404	 */
405	if (blkid_le32(es->s_flags) & EXT2_FLAGS_TEST_FILESYS) {
406		if (system_supports_ext4dev() || !system_supports_ext4())
407			return -BLKID_ERR_PARAM;
408	}
409    	get_ext2_info(probe->dev, id, buf);
410	return 0;
411}
412
413static int probe_ext3(struct blkid_probe *probe, struct blkid_magic *id,
414		      unsigned char *buf)
415{
416	struct ext2_super_block *es;
417	es = (struct ext2_super_block *)buf;
418
419	/* ext3 requires journal */
420	if (!(blkid_le32(es->s_feature_compat) &
421	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
422		return -BLKID_ERR_PARAM;
423
424	/* Any features which ext3 doesn't understand */
425	if ((blkid_le32(es->s_feature_ro_compat) &
426	     EXT3_FEATURE_RO_COMPAT_UNSUPPORTED) ||
427	    (blkid_le32(es->s_feature_incompat) &
428	     EXT3_FEATURE_INCOMPAT_UNSUPPORTED))
429		return -BLKID_ERR_PARAM;
430
431    	get_ext2_info(probe->dev, id, buf);
432	return 0;
433}
434
435static int probe_ext2(struct blkid_probe *probe, struct blkid_magic *id,
436		      unsigned char *buf)
437{
438	struct ext2_super_block *es;
439
440	es = (struct ext2_super_block *)buf;
441
442	/* Distinguish between ext3 and ext2 */
443	if ((blkid_le32(es->s_feature_compat) &
444	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
445		return -BLKID_ERR_PARAM;
446
447	/* Any features which ext2 doesn't understand */
448	if ((blkid_le32(es->s_feature_ro_compat) &
449	     EXT2_FEATURE_RO_COMPAT_UNSUPPORTED) ||
450	    (blkid_le32(es->s_feature_incompat) &
451	     EXT2_FEATURE_INCOMPAT_UNSUPPORTED))
452		return -BLKID_ERR_PARAM;
453
454	/*
455	 * If ext2 is not present, but ext4 or ext4dev are, then
456	 * disclaim we are ext2
457	 */
458	if (!system_supports_ext2() &&
459	    (system_supports_ext4() || system_supports_ext4dev()) &&
460	    linux_version_code() >= EXT4_SUPPORTS_EXT2)
461		return -BLKID_ERR_PARAM;
462
463	get_ext2_info(probe->dev, id, buf);
464	return 0;
465}
466
467static int probe_jbd(struct blkid_probe *probe, struct blkid_magic *id,
468		     unsigned char *buf)
469{
470	struct ext2_super_block *es = (struct ext2_super_block *) buf;
471
472	if (!(blkid_le32(es->s_feature_incompat) &
473	      EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
474		return -BLKID_ERR_PARAM;
475
476	get_ext2_info(probe->dev, id, buf);
477
478	return 0;
479}
480
481#define FAT_ATTR_VOLUME_ID		0x08
482#define FAT_ATTR_DIR			0x10
483#define FAT_ATTR_LONG_NAME		0x0f
484#define FAT_ATTR_MASK			0x3f
485#define FAT_ENTRY_FREE			0xe5
486
487static const char *no_name = "NO NAME    ";
488
489static unsigned char *search_fat_label(struct vfat_dir_entry *dir, int count)
490{
491	int i;
492
493	for (i = 0; i < count; i++) {
494		if (dir[i].name[0] == 0x00)
495			break;
496
497		if ((dir[i].name[0] == FAT_ENTRY_FREE) ||
498		    (dir[i].cluster_high != 0 || dir[i].cluster_low != 0) ||
499		    ((dir[i].attr & FAT_ATTR_MASK) == FAT_ATTR_LONG_NAME))
500			continue;
501
502		if ((dir[i].attr & (FAT_ATTR_VOLUME_ID | FAT_ATTR_DIR)) ==
503		    FAT_ATTR_VOLUME_ID) {
504			return dir[i].name;
505		}
506	}
507	return 0;
508}
509
510/* FAT label extraction from the root directory taken from Kay
511 * Sievers's volume_id library */
512static int probe_fat(struct blkid_probe *probe,
513		      struct blkid_magic *id __BLKID_ATTR((unused)),
514		      unsigned char *buf)
515{
516	struct vfat_super_block *vs = (struct vfat_super_block *) buf;
517	struct msdos_super_block *ms = (struct msdos_super_block *) buf;
518	struct vfat_dir_entry *dir;
519	char serno[10];
520	const unsigned char *label = 0, *vol_label = 0, *tmp;
521	unsigned char	*vol_serno;
522	int label_len = 0, maxloop = 100;
523	__u16 sector_size, dir_entries, reserved;
524	__u32 sect_count, fat_size, dir_size, cluster_count, fat_length;
525	__u32 buf_size, start_data_sect, next, root_start, root_dir_entries;
526
527	/* sector size check */
528	tmp = (unsigned char *)&ms->ms_sector_size;
529	sector_size = tmp[0] + (tmp[1] << 8);
530	if (sector_size != 0x200 && sector_size != 0x400 &&
531	    sector_size != 0x800 && sector_size != 0x1000)
532		return 1;
533
534	tmp = (unsigned char *)&ms->ms_dir_entries;
535	dir_entries = tmp[0] + (tmp[1] << 8);
536	reserved =  blkid_le16(ms->ms_reserved);
537	tmp = (unsigned char *)&ms->ms_sectors;
538	sect_count = tmp[0] + (tmp[1] << 8);
539	if (sect_count == 0)
540		sect_count = blkid_le32(ms->ms_total_sect);
541
542	fat_length = blkid_le16(ms->ms_fat_length);
543	if (fat_length == 0)
544		fat_length = blkid_le32(vs->vs_fat32_length);
545
546	fat_size = fat_length * ms->ms_fats;
547	dir_size = ((dir_entries * sizeof(struct vfat_dir_entry)) +
548			(sector_size-1)) / sector_size;
549
550	cluster_count = sect_count - (reserved + fat_size + dir_size);
551	if (ms->ms_cluster_size == 0)
552		return 1;
553	cluster_count /= ms->ms_cluster_size;
554
555	if (cluster_count > FAT32_MAX)
556		return 1;
557
558	if (ms->ms_fat_length) {
559		/* the label may be an attribute in the root directory */
560		root_start = (reserved + fat_size) * sector_size;
561		root_dir_entries = vs->vs_dir_entries[0] +
562			(vs->vs_dir_entries[1] << 8);
563
564		buf_size = root_dir_entries * sizeof(struct vfat_dir_entry);
565		dir = (struct vfat_dir_entry *) get_buffer(probe, root_start,
566							   buf_size);
567		if (dir)
568			vol_label = search_fat_label(dir, root_dir_entries);
569
570		if (!vol_label || !memcmp(vol_label, no_name, 11))
571			vol_label = ms->ms_label;
572		vol_serno = ms->ms_serno;
573
574		blkid_set_tag(probe->dev, "SEC_TYPE", "msdos",
575			      sizeof("msdos"));
576	} else {
577		/* Search the FAT32 root dir for the label attribute */
578		buf_size = vs->vs_cluster_size * sector_size;
579		start_data_sect = reserved + fat_size;
580
581		next = blkid_le32(vs->vs_root_cluster);
582		while (next && --maxloop) {
583			__u32 next_sect_off;
584			__u64 next_off, fat_entry_off;
585			int count;
586
587			next_sect_off = (next - 2) * vs->vs_cluster_size;
588			next_off = (start_data_sect + next_sect_off) *
589				sector_size;
590
591			dir = (struct vfat_dir_entry *)
592				get_buffer(probe, next_off, buf_size);
593			if (dir == NULL)
594				break;
595
596			count = buf_size / sizeof(struct vfat_dir_entry);
597
598			vol_label = search_fat_label(dir, count);
599			if (vol_label)
600				break;
601
602			/* get FAT entry */
603			fat_entry_off = (reserved * sector_size) +
604				(next * sizeof(__u32));
605			buf = get_buffer(probe, fat_entry_off, buf_size);
606			if (buf == NULL)
607				break;
608
609			/* set next cluster */
610			next = blkid_le32(*((__u32 *) buf) & 0x0fffffff);
611		}
612
613		if (!vol_label || !memcmp(vol_label, no_name, 11))
614			vol_label = vs->vs_label;
615		vol_serno = vs->vs_serno;
616	}
617
618	if (vol_label && memcmp(vol_label, no_name, 11)) {
619		if ((label_len = figure_label_len(vol_label, 11)))
620			label = vol_label;
621	}
622
623	/* We can't just print them as %04X, because they are unaligned */
624	sprintf(serno, "%02X%02X-%02X%02X", vol_serno[3], vol_serno[2],
625		vol_serno[1], vol_serno[0]);
626
627	blkid_set_tag(probe->dev, "LABEL", (const char *) label, label_len);
628	blkid_set_tag(probe->dev, "UUID", serno, sizeof(serno)-1);
629
630	return 0;
631}
632
633/*
634 * The FAT filesystem could be without a magic string in superblock
635 * (e.g. old floppies).  This heuristic for FAT detection is inspired
636 * by http://vrfy.org/projects/volume_id/ and Linux kernel.
637 * [7-Jul-2005, Karel Zak <kzak@redhat.com>]
638 */
639static int probe_fat_nomagic(struct blkid_probe *probe,
640			     struct blkid_magic *id __BLKID_ATTR((unused)),
641			     unsigned char *buf)
642{
643	struct msdos_super_block *ms;
644
645	ms = (struct msdos_super_block *)buf;
646
647	/* heads check */
648	if (ms->ms_heads == 0)
649		return 1;
650
651	/* cluster size check*/
652	if (ms->ms_cluster_size == 0 ||
653	    (ms->ms_cluster_size & (ms->ms_cluster_size-1)))
654		return 1;
655
656	/* media check */
657	if (ms->ms_media < 0xf8 && ms->ms_media != 0xf0)
658		return 1;
659
660	/* fat counts(Linux kernel expects at least 1 FAT table) */
661	if (!ms->ms_fats)
662		return 1;
663
664	/*
665	 * OS/2 and apparently DFSee will place a FAT12/16-like
666	 * pseudo-superblock in the first 512 bytes of non-FAT
667	 * filesystems --- at least JFS and HPFS, and possibly others.
668	 * So we explicitly check for those filesystems at the
669	 * FAT12/16 filesystem magic field identifier, and if they are
670	 * present, we rule this out as a FAT filesystem, despite the
671	 * FAT-like pseudo-header.
672         */
673	if ((memcmp(ms->ms_magic, "JFS     ", 8) == 0) ||
674	    (memcmp(ms->ms_magic, "HPFS    ", 8) == 0))
675		return 1;
676
677	return probe_fat(probe, id, buf);
678}
679
680static int probe_ntfs(struct blkid_probe *probe,
681		      struct blkid_magic *id __BLKID_ATTR((unused)),
682		      unsigned char *buf)
683{
684	struct ntfs_super_block *ns;
685	struct master_file_table_record *mft;
686	struct file_attribute *attr;
687	char		uuid_str[17], label_str[129], *cp;
688	int		bytes_per_sector, sectors_per_cluster;
689	int		mft_record_size, attr_off, attr_len;
690	unsigned int	i, attr_type, val_len;
691	int		val_off;
692	__u64		nr_clusters;
693	blkid_loff_t off;
694	unsigned char *buf_mft, *val;
695
696	ns = (struct ntfs_super_block *) buf;
697
698	bytes_per_sector = ns->bios_parameter_block[0] +
699		(ns->bios_parameter_block[1]  << 8);
700	sectors_per_cluster = ns->bios_parameter_block[2];
701
702	if ((bytes_per_sector < 512) || (sectors_per_cluster == 0))
703		return 1;
704
705	if (ns->cluster_per_mft_record < 0)
706		mft_record_size = 1 << (0-ns->cluster_per_mft_record);
707	else
708		mft_record_size = ns->cluster_per_mft_record *
709			sectors_per_cluster * bytes_per_sector;
710	nr_clusters = blkid_le64(ns->number_of_sectors) / sectors_per_cluster;
711
712	if ((blkid_le64(ns->mft_cluster_location) > nr_clusters) ||
713	    (blkid_le64(ns->mft_mirror_cluster_location) > nr_clusters))
714		return 1;
715
716	off = blkid_le64(ns->mft_mirror_cluster_location) *
717		bytes_per_sector * sectors_per_cluster;
718
719	buf_mft = get_buffer(probe, off, mft_record_size);
720	if (!buf_mft)
721		return 1;
722
723	if (memcmp(buf_mft, "FILE", 4))
724		return 1;
725
726	off = blkid_le64(ns->mft_cluster_location) * bytes_per_sector *
727		sectors_per_cluster;
728
729	buf_mft = get_buffer(probe, off, mft_record_size);
730	if (!buf_mft)
731		return 1;
732
733	if (memcmp(buf_mft, "FILE", 4))
734		return 1;
735
736	off += MFT_RECORD_VOLUME * mft_record_size;
737
738	buf_mft = get_buffer(probe, off, mft_record_size);
739	if (!buf_mft)
740		return 1;
741
742	if (memcmp(buf_mft, "FILE", 4))
743		return 1;
744
745	mft = (struct master_file_table_record *) buf_mft;
746
747	attr_off = blkid_le16(mft->attrs_offset);
748	label_str[0] = 0;
749
750	while (1) {
751		attr = (struct file_attribute *) (buf_mft + attr_off);
752		attr_len = blkid_le16(attr->len);
753		attr_type = blkid_le32(attr->type);
754		val_off = blkid_le16(attr->value_offset);
755		val_len = blkid_le32(attr->value_len);
756
757		attr_off += attr_len;
758
759		if ((attr_off > mft_record_size) ||
760		    (attr_len == 0))
761			break;
762
763		if (attr_type == MFT_RECORD_ATTR_END)
764			break;
765
766		if (attr_type == MFT_RECORD_ATTR_VOLUME_NAME) {
767			if (val_len > sizeof(label_str))
768				val_len = sizeof(label_str)-1;
769
770			for (i=0, cp=label_str; i < val_len; i+=2,cp++) {
771				val = ((__u8 *) attr) + val_off + i;
772				*cp = val[0];
773				if (val[1])
774					*cp = '?';
775			}
776			*cp = 0;
777		}
778	}
779
780	sprintf(uuid_str, "%016llX", blkid_le64(ns->volume_serial));
781	blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
782	if (label_str[0])
783		blkid_set_tag(probe->dev, "LABEL", label_str, 0);
784	return 0;
785}
786
787
788static int probe_xfs(struct blkid_probe *probe,
789		     struct blkid_magic *id __BLKID_ATTR((unused)),
790		     unsigned char *buf)
791{
792	struct xfs_super_block *xs;
793	const char *label = 0;
794
795	xs = (struct xfs_super_block *)buf;
796
797	if (strlen(xs->xs_fname))
798		label = xs->xs_fname;
799	blkid_set_tag(probe->dev, "LABEL", label, sizeof(xs->xs_fname));
800	set_uuid(probe->dev, xs->xs_uuid, 0);
801	return 0;
802}
803
804static int probe_reiserfs(struct blkid_probe *probe,
805			  struct blkid_magic *id, unsigned char *buf)
806{
807	struct reiserfs_super_block *rs = (struct reiserfs_super_block *) buf;
808	unsigned int blocksize;
809	const char *label = 0;
810
811	blocksize = blkid_le16(rs->rs_blocksize);
812
813	/* The blocksize must be at least 1k */
814	if ((blocksize >> 10) == 0)
815		return -BLKID_ERR_PARAM;
816
817	/* If the superblock is inside the journal, we have the wrong one */
818	if (id->bim_kboff/(blocksize>>10) > blkid_le32(rs->rs_journal_block))
819		return -BLKID_ERR_BIG;
820
821	/* LABEL/UUID are only valid for later versions of Reiserfs v3.6. */
822	if (id->bim_magic[6] == '2' || id->bim_magic[6] == '3') {
823		if (strlen(rs->rs_label))
824			label = rs->rs_label;
825		set_uuid(probe->dev, rs->rs_uuid, 0);
826	}
827	blkid_set_tag(probe->dev, "LABEL", label, sizeof(rs->rs_label));
828
829	return 0;
830}
831
832static int probe_reiserfs4(struct blkid_probe *probe,
833			   struct blkid_magic *id __BLKID_ATTR((unused)),
834			   unsigned char *buf)
835{
836	struct reiser4_super_block *rs4 = (struct reiser4_super_block *) buf;
837	const unsigned char *label = 0;
838
839	if (strlen((char *) rs4->rs4_label))
840		label = rs4->rs4_label;
841	set_uuid(probe->dev, rs4->rs4_uuid, 0);
842	blkid_set_tag(probe->dev, "LABEL", (const char *) label,
843		      sizeof(rs4->rs4_label));
844
845	return 0;
846}
847
848static int probe_jfs(struct blkid_probe *probe,
849		     struct blkid_magic *id __BLKID_ATTR((unused)),
850		     unsigned char *buf)
851{
852	struct jfs_super_block *js;
853	const char *label = 0;
854
855	js = (struct jfs_super_block *)buf;
856
857	if (blkid_le32(js->js_bsize) != (1 << blkid_le16(js->js_l2bsize)))
858		return 1;
859
860	if (blkid_le32(js->js_pbsize) != (1 << blkid_le16(js->js_l2pbsize)))
861		return 1;
862
863	if ((blkid_le16(js->js_l2bsize) - blkid_le16(js->js_l2pbsize)) !=
864	    blkid_le16(js->js_l2bfactor))
865		return 1;
866
867	if (strlen((char *) js->js_label))
868		label = (char *) js->js_label;
869	blkid_set_tag(probe->dev, "LABEL", label, sizeof(js->js_label));
870	set_uuid(probe->dev, js->js_uuid, 0);
871	return 0;
872}
873
874static int probe_zfs(struct blkid_probe *probe, struct blkid_magic *id,
875		     unsigned char *buf)
876{
877#if 0
878	char *vdev_label;
879	const char *pool_name = 0;
880
881	/* read nvpair data for pool name, pool GUID (complex) */
882	blkid_set_tag(probe->dev, "LABEL", pool_name, sizeof(pool_name));
883	set_uuid(probe->dev, pool_guid, 0);
884#endif
885	return 0;
886}
887
888static int probe_luks(struct blkid_probe *probe,
889		       struct blkid_magic *id __BLKID_ATTR((unused)),
890		       unsigned char *buf)
891{
892	char uuid[40];
893
894	/* 168 is the offset to the 40 character uuid:
895	 * http://luks.endorphin.org/LUKS-on-disk-format.pdf */
896	strncpy(uuid, (char *) buf+168, 40);
897	blkid_set_tag(probe->dev, "UUID", uuid, sizeof(uuid));
898	return 0;
899}
900
901static int probe_romfs(struct blkid_probe *probe,
902		       struct blkid_magic *id __BLKID_ATTR((unused)),
903		       unsigned char *buf)
904{
905	struct romfs_super_block *ros;
906	const char *label = 0;
907
908	ros = (struct romfs_super_block *)buf;
909
910	if (strlen((char *) ros->ros_volume))
911		label = (char *) ros->ros_volume;
912	blkid_set_tag(probe->dev, "LABEL", label, 0);
913	return 0;
914}
915
916static int probe_cramfs(struct blkid_probe *probe,
917			struct blkid_magic *id __BLKID_ATTR((unused)),
918			unsigned char *buf)
919{
920	struct cramfs_super_block *csb;
921	const char *label = 0;
922
923	csb = (struct cramfs_super_block *)buf;
924
925	if (strlen((char *) csb->name))
926		label = (char *) csb->name;
927	blkid_set_tag(probe->dev, "LABEL", label, 0);
928	return 0;
929}
930
931static int probe_swap0(struct blkid_probe *probe,
932		       struct blkid_magic *id __BLKID_ATTR((unused)),
933		       unsigned char *buf __BLKID_ATTR((unused)))
934{
935	blkid_set_tag(probe->dev, "UUID", 0, 0);
936	blkid_set_tag(probe->dev, "LABEL", 0, 0);
937	return 0;
938}
939
940static int probe_swap1(struct blkid_probe *probe,
941		       struct blkid_magic *id,
942		       unsigned char *buf __BLKID_ATTR((unused)))
943{
944	struct swap_id_block *sws;
945
946	probe_swap0(probe, id, buf);
947	/*
948	 * Version 1 swap headers are always located at offset of 1024
949	 * bytes, although the swap signature itself is located at the
950	 * end of the page (which may vary depending on hardware
951	 * pagesize).
952	 */
953	sws = (struct swap_id_block *) get_buffer(probe, 1024, 1024);
954	if (!sws)
955		return 1;
956
957	/* check for wrong version or zeroed pagecount, for sanity */
958	if (!memcmp(id->bim_magic, "SWAPSPACE2", id->bim_len) &&
959			(sws->sws_version != 1 || sws->sws_lastpage == 0))
960		return 1;
961
962	/* arbitrary sanity check.. is there any garbage down there? */
963	if (sws->sws_pad[32] == 0 && sws->sws_pad[33] == 0)  {
964		if (sws->sws_volume[0])
965			blkid_set_tag(probe->dev, "LABEL", sws->sws_volume,
966				      sizeof(sws->sws_volume));
967		if (sws->sws_uuid[0])
968			set_uuid(probe->dev, sws->sws_uuid, 0);
969	}
970	return 0;
971}
972
973static int probe_iso9660(struct blkid_probe *probe,
974			 struct blkid_magic *id __BLKID_ATTR((unused)),
975			 unsigned char *buf)
976{
977	struct iso_volume_descriptor *iso;
978	const unsigned char *label;
979
980	iso = (struct iso_volume_descriptor *) buf;
981	label = iso->volume_id;
982
983	blkid_set_tag(probe->dev, "LABEL", (const char *) label,
984		      figure_label_len(label, 32));
985	return 0;
986}
987
988
989static const char
990*udf_magic[] = { "BEA01", "BOOT2", "CD001", "CDW02", "NSR02",
991		 "NSR03", "TEA01", 0 };
992
993static int probe_udf(struct blkid_probe *probe,
994		     struct blkid_magic *id __BLKID_ATTR((unused)),
995		     unsigned char *buf __BLKID_ATTR((unused)))
996{
997	int j, bs;
998	struct iso_volume_descriptor *isosb;
999	const char ** m;
1000
1001	/* determine the block size by scanning in 2K increments
1002	   (block sizes larger than 2K will be null padded) */
1003	for (bs = 1; bs < 16; bs++) {
1004		isosb = (struct iso_volume_descriptor *)
1005			get_buffer(probe, bs*2048+32768, sizeof(isosb));
1006		if (!isosb)
1007			return 1;
1008		if (isosb->vd_id[0])
1009			break;
1010	}
1011
1012	/* Scan up to another 64 blocks looking for additional VSD's */
1013	for (j = 1; j < 64; j++) {
1014		if (j > 1) {
1015			isosb = (struct iso_volume_descriptor *)
1016				get_buffer(probe, j*bs*2048+32768,
1017					   sizeof(isosb));
1018			if (!isosb)
1019				return 1;
1020		}
1021		/* If we find NSR0x then call it udf:
1022		   NSR01 for UDF 1.00
1023		   NSR02 for UDF 1.50
1024		   NSR03 for UDF 2.00 */
1025		if (!memcmp(isosb->vd_id, "NSR0", 4))
1026			return probe_iso9660(probe, id, buf);
1027		for (m = udf_magic; *m; m++)
1028			if (!memcmp(*m, isosb->vd_id, 5))
1029				break;
1030		if (*m == 0)
1031			return 1;
1032	}
1033	return 1;
1034}
1035
1036static int probe_ocfs(struct blkid_probe *probe,
1037		      struct blkid_magic *id __BLKID_ATTR((unused)),
1038		      unsigned char *buf)
1039{
1040	struct ocfs_volume_header ovh;
1041	struct ocfs_volume_label ovl;
1042	__u32 major;
1043
1044	memcpy(&ovh, buf, sizeof(ovh));
1045	memcpy(&ovl, buf+512, sizeof(ovl));
1046
1047	major = ocfsmajor(ovh);
1048	if (major == 1)
1049		blkid_set_tag(probe->dev,"SEC_TYPE","ocfs1",sizeof("ocfs1"));
1050	else if (major >= 9)
1051		blkid_set_tag(probe->dev,"SEC_TYPE","ntocfs",sizeof("ntocfs"));
1052
1053	blkid_set_tag(probe->dev, "LABEL", ovl.label, ocfslabellen(ovl));
1054	blkid_set_tag(probe->dev, "MOUNT", ovh.mount, ocfsmountlen(ovh));
1055	set_uuid(probe->dev, ovl.vol_id, 0);
1056	return 0;
1057}
1058
1059static int probe_ocfs2(struct blkid_probe *probe,
1060		       struct blkid_magic *id __BLKID_ATTR((unused)),
1061		       unsigned char *buf)
1062{
1063	struct ocfs2_super_block *osb;
1064
1065	osb = (struct ocfs2_super_block *)buf;
1066
1067	blkid_set_tag(probe->dev, "LABEL", osb->s_label, sizeof(osb->s_label));
1068	set_uuid(probe->dev, osb->s_uuid, 0);
1069	return 0;
1070}
1071
1072static int probe_oracleasm(struct blkid_probe *probe,
1073			   struct blkid_magic *id __BLKID_ATTR((unused)),
1074			   unsigned char *buf)
1075{
1076	struct oracle_asm_disk_label *dl;
1077
1078	dl = (struct oracle_asm_disk_label *)buf;
1079
1080	blkid_set_tag(probe->dev, "LABEL", dl->dl_id, sizeof(dl->dl_id));
1081	return 0;
1082}
1083
1084static int probe_gfs(struct blkid_probe *probe,
1085		     struct blkid_magic *id __BLKID_ATTR((unused)),
1086		     unsigned char *buf)
1087{
1088	struct gfs2_sb *sbd;
1089	const char *label = 0;
1090
1091	sbd = (struct gfs2_sb *)buf;
1092
1093	if (blkid_be32(sbd->sb_fs_format) == GFS_FORMAT_FS &&
1094	    blkid_be32(sbd->sb_multihost_format) == GFS_FORMAT_MULTI)
1095	{
1096		blkid_set_tag(probe->dev, "UUID", 0, 0);
1097
1098		if (strlen(sbd->sb_locktable))
1099			label = sbd->sb_locktable;
1100		blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
1101		return 0;
1102	}
1103	return 1;
1104}
1105
1106static int probe_gfs2(struct blkid_probe *probe,
1107		     struct blkid_magic *id __BLKID_ATTR((unused)),
1108		     unsigned char *buf)
1109{
1110	struct gfs2_sb *sbd;
1111	const char *label = 0;
1112
1113	sbd = (struct gfs2_sb *)buf;
1114
1115	if (blkid_be32(sbd->sb_fs_format) == GFS2_FORMAT_FS &&
1116	    blkid_be32(sbd->sb_multihost_format) == GFS2_FORMAT_MULTI)
1117	{
1118		blkid_set_tag(probe->dev, "UUID", 0, 0);
1119
1120		if (strlen(sbd->sb_locktable))
1121			label = sbd->sb_locktable;
1122		blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
1123		return 0;
1124	}
1125	return 1;
1126}
1127
1128static void unicode_16be_to_utf8(unsigned char *str, int out_len,
1129				 const unsigned char *buf, int in_len)
1130{
1131	int i, j;
1132	unsigned int c;
1133
1134	for (i = j = 0; i + 2 <= in_len; i += 2) {
1135		c = (buf[i] << 8) | buf[i+1];
1136		if (c == 0) {
1137			str[j] = '\0';
1138			break;
1139		} else if (c < 0x80) {
1140			if (j+1 >= out_len)
1141				break;
1142			str[j++] = (unsigned char) c;
1143		} else if (c < 0x800) {
1144			if (j+2 >= out_len)
1145				break;
1146			str[j++] = (unsigned char) (0xc0 | (c >> 6));
1147			str[j++] = (unsigned char) (0x80 | (c & 0x3f));
1148		} else {
1149			if (j+3 >= out_len)
1150				break;
1151			str[j++] = (unsigned char) (0xe0 | (c >> 12));
1152			str[j++] = (unsigned char) (0x80 | ((c >> 6) & 0x3f));
1153			str[j++] = (unsigned char) (0x80 | (c & 0x3f));
1154		}
1155	}
1156	str[j] = '\0';
1157}
1158
1159static int probe_hfs(struct blkid_probe *probe __BLKID_ATTR((unused)),
1160			 struct blkid_magic *id __BLKID_ATTR((unused)),
1161			 unsigned char *buf)
1162{
1163	struct hfs_mdb *hfs = (struct hfs_mdb *)buf;
1164	unsigned long long *uuid_ptr;
1165	char	uuid_str[17];
1166	__u64	uuid;
1167
1168	if ((memcmp(hfs->embed_sig, "H+", 2) == 0) ||
1169	    (memcmp(hfs->embed_sig, "HX", 2) == 0))
1170		return 1;	/* Not hfs, but an embedded HFS+ */
1171
1172	uuid_ptr = (unsigned long long *)hfs->finder_info.id;
1173	uuid = blkid_le64(*uuid_ptr);
1174	if (uuid) {
1175		sprintf(uuid_str, "%016llX", uuid);
1176		blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
1177	}
1178	blkid_set_tag(probe->dev, "LABEL", (char *)hfs->label, hfs->label_len);
1179	return 0;
1180}
1181
1182
1183static int probe_hfsplus(struct blkid_probe *probe,
1184			 struct blkid_magic *id,
1185			 unsigned char *buf)
1186{
1187	struct hfsplus_extent extents[HFSPLUS_EXTENT_COUNT];
1188	struct hfsplus_bnode_descriptor *descr;
1189	struct hfsplus_bheader_record *bnode;
1190	struct hfsplus_catalog_key *key;
1191	struct hfsplus_vol_header *hfsplus;
1192	struct hfs_mdb *sbd = (struct hfs_mdb *) buf;
1193	unsigned int alloc_block_size;
1194	unsigned int alloc_first_block;
1195	unsigned int embed_first_block;
1196	unsigned int off = 0;
1197	unsigned int blocksize;
1198	unsigned int cat_block;
1199	unsigned int ext_block_start;
1200	unsigned int ext_block_count;
1201	unsigned int record_count;
1202	unsigned int leaf_node_head;
1203	unsigned int leaf_node_count;
1204	unsigned int leaf_node_size;
1205	unsigned int leaf_block;
1206	unsigned int label_len;
1207	unsigned long long *uuid_ptr;
1208	__u64 leaf_off, uuid;
1209	char	uuid_str[17], label[512];
1210	int ext;
1211
1212	/* Check for a HFS+ volume embedded in a HFS volume */
1213	if (memcmp(sbd->signature, "BD", 2) == 0) {
1214		if ((memcmp(sbd->embed_sig, "H+", 2) != 0) &&
1215		    (memcmp(sbd->embed_sig, "HX", 2) != 0))
1216			/* This must be an HFS volume, so fail */
1217			return 1;
1218
1219		alloc_block_size = blkid_be32(sbd->al_blk_size);
1220		alloc_first_block = blkid_be16(sbd->al_bl_st);
1221		embed_first_block = blkid_be16(sbd->embed_startblock);
1222		off = (alloc_first_block * 512) +
1223			(embed_first_block * alloc_block_size);
1224		buf = get_buffer(probe, off + (id->bim_kboff * 1024),
1225				 sizeof(sbd));
1226		if (!buf)
1227			return 1;
1228
1229		hfsplus = (struct hfsplus_vol_header *) buf;
1230	}
1231
1232	hfsplus = (struct hfsplus_vol_header *) buf;
1233
1234	if ((memcmp(hfsplus->signature, "H+", 2) != 0) &&
1235	    (memcmp(hfsplus->signature, "HX", 2) != 0))
1236		return 1;
1237
1238	uuid_ptr = (unsigned long long *)hfsplus->finder_info.id;
1239	uuid = blkid_le64(*uuid_ptr);
1240	if (uuid) {
1241		sprintf(uuid_str, "%016llX", uuid);
1242		blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
1243	}
1244
1245	blocksize = blkid_be32(hfsplus->blocksize);
1246	memcpy(extents, hfsplus->cat_file.extents, sizeof(extents));
1247	cat_block = blkid_be32(extents[0].start_block);
1248
1249	buf = get_buffer(probe, off + (cat_block * blocksize), 0x2000);
1250	if (!buf)
1251		return 0;
1252
1253	bnode = (struct hfsplus_bheader_record *)
1254		&buf[sizeof(struct hfsplus_bnode_descriptor)];
1255
1256	leaf_node_head = blkid_be32(bnode->leaf_head);
1257	leaf_node_size = blkid_be16(bnode->node_size);
1258	leaf_node_count = blkid_be32(bnode->leaf_count);
1259	if (leaf_node_count == 0)
1260		return 0;
1261
1262	leaf_block = (leaf_node_head * leaf_node_size) / blocksize;
1263
1264	/* get physical location */
1265	for (ext = 0; ext < HFSPLUS_EXTENT_COUNT; ext++) {
1266		ext_block_start = blkid_be32(extents[ext].start_block);
1267		ext_block_count = blkid_be32(extents[ext].block_count);
1268		if (ext_block_count == 0)
1269			return 0;
1270
1271		/* this is our extent */
1272		if (leaf_block < ext_block_count)
1273			break;
1274
1275		leaf_block -= ext_block_count;
1276	}
1277	if (ext == HFSPLUS_EXTENT_COUNT)
1278		return 0;
1279
1280	leaf_off = (ext_block_start + leaf_block) * blocksize;
1281
1282	buf = get_buffer(probe, off + leaf_off, leaf_node_size);
1283	if (!buf)
1284		return 0;
1285
1286	descr = (struct hfsplus_bnode_descriptor *) buf;
1287	record_count = blkid_be16(descr->num_recs);
1288	if (record_count == 0)
1289		return 0;
1290
1291	if (descr->type != HFS_NODE_LEAF)
1292		return 0;
1293
1294	key = (struct hfsplus_catalog_key *)
1295		&buf[sizeof(struct hfsplus_bnode_descriptor)];
1296
1297	if (blkid_be32(key->parent_id) != HFSPLUS_POR_CNID)
1298		return 0;
1299
1300	label_len = blkid_be16(key->unicode_len) * 2;
1301	unicode_16be_to_utf8((unsigned char *)label, sizeof(label),
1302			     key->unicode, label_len);
1303	blkid_set_tag(probe->dev, "LABEL", label, 0);
1304	return 0;
1305}
1306
1307#define LVM2_LABEL_SIZE 512
1308static unsigned int lvm2_calc_crc(const void *buf, unsigned int size)
1309{
1310	static const unsigned int crctab[] = {
1311		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1312		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1313		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1314		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1315	};
1316	unsigned int i, crc = 0xf597a6cf;
1317	const __u8 *data = (const __u8 *) buf;
1318
1319	for (i = 0; i < size; i++) {
1320		crc ^= *data++;
1321		crc = (crc >> 4) ^ crctab[crc & 0xf];
1322		crc = (crc >> 4) ^ crctab[crc & 0xf];
1323	}
1324	return crc;
1325}
1326
1327static int probe_lvm2(struct blkid_probe *probe,
1328			struct blkid_magic *id,
1329			unsigned char *buf)
1330{
1331	int sector = (id->bim_kboff) << 1;
1332	struct lvm2_pv_label_header *label= (struct lvm2_pv_label_header *)buf;
1333	char *p, *q, uuid[40];
1334	unsigned int i, b;
1335
1336	/* buf is at 0k or 1k offset; find label inside */
1337	if (memcmp(buf, "LABELONE", 8) == 0) {
1338		label = (struct lvm2_pv_label_header *)buf;
1339	} else if (memcmp(buf + 512, "LABELONE", 8) == 0) {
1340		label = (struct lvm2_pv_label_header *)(buf + 512);
1341		sector++;
1342	} else {
1343		return 1;
1344	}
1345
1346	if (blkid_le64(label->sector_xl) != (unsigned) sector) {
1347		DBG(DEBUG_PROBE,
1348		    printf("LVM2: label for sector %llu found at sector %d\n",
1349			   blkid_le64(label->sector_xl), sector));
1350		return 1;
1351	}
1352
1353	if (lvm2_calc_crc(&label->offset_xl, LVM2_LABEL_SIZE -
1354			  ((char *)&label->offset_xl - (char *)label)) !=
1355			blkid_le32(label->crc_xl)) {
1356		DBG(DEBUG_PROBE,
1357		    printf("LVM2: label checksum incorrect at sector %d\n",
1358			   sector));
1359		return 1;
1360	}
1361
1362	for (i=0, b=1, p=uuid, q= (char *) label->pv_uuid; i <= 32;
1363	     i++, b <<= 1) {
1364		if (b & 0x4444440)
1365			*p++ = '-';
1366		*p++ = *q++;
1367	}
1368
1369	blkid_set_tag(probe->dev, "UUID", uuid, LVM2_ID_LEN+6);
1370
1371	return 0;
1372}
1373
1374static int probe_btrfs(struct blkid_probe *probe,
1375			struct blkid_magic *id,
1376			unsigned char *buf)
1377{
1378	struct btrfs_super_block *bs;
1379	const char *label = 0;
1380
1381	bs = (struct btrfs_super_block *)buf;
1382
1383	if (strlen(bs->label))
1384		label = bs->label;
1385	blkid_set_tag(probe->dev, "LABEL", label, sizeof(bs->label));
1386	set_uuid(probe->dev, bs->fsid, 0);
1387	return 0;
1388}
1389/*
1390 * Various filesystem magics that we can check for.  Note that kboff and
1391 * sboff are in kilobytes and bytes respectively.  All magics are in
1392 * byte strings so we don't worry about endian issues.
1393 */
1394static struct blkid_magic type_array[] = {
1395/*  type     kboff   sboff len  magic			probe */
1396  { "oracleasm", 0,	32,  8, "ORCLDISK",		probe_oracleasm },
1397  { "ntfs",	 0,	 3,  8, "NTFS    ",		probe_ntfs },
1398  { "jbd",	 1,   0x38,  2, "\123\357",		probe_jbd },
1399  { "ext4dev",	 1,   0x38,  2, "\123\357",		probe_ext4dev },
1400  { "ext4",	 1,   0x38,  2, "\123\357",		probe_ext4 },
1401  { "ext3",	 1,   0x38,  2, "\123\357",		probe_ext3 },
1402  { "ext2",	 1,   0x38,  2, "\123\357",		probe_ext2 },
1403  { "reiserfs",	 8,   0x34,  8, "ReIsErFs",		probe_reiserfs },
1404  { "reiserfs", 64,   0x34,  9, "ReIsEr2Fs",		probe_reiserfs },
1405  { "reiserfs", 64,   0x34,  9, "ReIsEr3Fs",		probe_reiserfs },
1406  { "reiserfs", 64,   0x34,  8, "ReIsErFs",		probe_reiserfs },
1407  { "reiserfs",	 8,	20,  8, "ReIsErFs",		probe_reiserfs },
1408  { "reiser4",  64,	 0,  7, "ReIsEr4",		probe_reiserfs4 },
1409  { "gfs2",     64,      0,  4, "\x01\x16\x19\x70",     probe_gfs2 },
1410  { "gfs",      64,      0,  4, "\x01\x16\x19\x70",     probe_gfs },
1411  { "vfat",      0,   0x52,  5, "MSWIN",                probe_fat },
1412  { "vfat",      0,   0x52,  8, "FAT32   ",             probe_fat },
1413  { "vfat",      0,   0x36,  5, "MSDOS",                probe_fat },
1414  { "vfat",      0,   0x36,  8, "FAT16   ",             probe_fat },
1415  { "vfat",      0,   0x36,  8, "FAT12   ",             probe_fat },
1416  { "vfat",      0,      0,  1, "\353",                 probe_fat_nomagic },
1417  { "vfat",      0,      0,  1, "\351",                 probe_fat_nomagic },
1418  { "vfat",      0,  0x1fe,  2, "\125\252",             probe_fat_nomagic },
1419  { "minix",     1,   0x10,  2, "\177\023",             0 },
1420  { "minix",     1,   0x10,  2, "\217\023",             0 },
1421  { "minix",	 1,   0x10,  2, "\150\044",		0 },
1422  { "minix",	 1,   0x10,  2, "\170\044",		0 },
1423  { "vxfs",	 1,	 0,  4, "\365\374\001\245",	0 },
1424  { "xfs",	 0,	 0,  4, "XFSB",			probe_xfs },
1425  { "romfs",	 0,	 0,  8, "-rom1fs-",		probe_romfs },
1426  { "bfs",	 0,	 0,  4, "\316\372\173\033",	0 },
1427  { "cramfs",	 0,	 0,  4, "E=\315\050",		probe_cramfs },
1428  { "qnx4",	 0,	 4,  6, "QNX4FS",		0 },
1429  { "udf",	32,	 1,  5, "BEA01",		probe_udf },
1430  { "udf",	32,	 1,  5, "BOOT2",		probe_udf },
1431  { "udf",	32,	 1,  5, "CD001",		probe_udf },
1432  { "udf",	32,	 1,  5, "CDW02",		probe_udf },
1433  { "udf",	32,	 1,  5, "NSR02",		probe_udf },
1434  { "udf",	32,	 1,  5, "NSR03",		probe_udf },
1435  { "udf",	32,	 1,  5, "TEA01",		probe_udf },
1436  { "iso9660",	32,	 1,  5, "CD001",		probe_iso9660 },
1437  { "iso9660",	32,	 9,  5, "CDROM",		probe_iso9660 },
1438  { "jfs",	32,	 0,  4, "JFS1",			probe_jfs },
1439  { "zfs",       8,	 0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
1440  { "zfs",       8,	 0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
1441  { "zfs",     264,	 0,  8, "\0\0\x02\xf5\xb0\x07\xb1\x0c", probe_zfs },
1442  { "zfs",     264,	 0,  8, "\x0c\xb1\x07\xb0\xf5\x02\0\0", probe_zfs },
1443  { "hfsplus",	 1,	 0,  2, "BD",			probe_hfsplus },
1444  { "hfsplus",	 1,	 0,  2, "H+",			probe_hfsplus },
1445  { "hfsplus",	 1,	 0,  2, "HX",			probe_hfsplus },
1446  { "hfs",	 1,	 0,  2, "BD",			probe_hfs },
1447  { "ufs",	 8,  0x55c,  4, "T\031\001\000",	0 },
1448  { "hpfs",	 8,	 0,  4, "I\350\225\371",	0 },
1449  { "sysv",	 0,  0x3f8,  4, "\020~\030\375",	0 },
1450  { "swap",	 0,  0xff6, 10, "SWAP-SPACE",		probe_swap0 },
1451  { "swap",	 0,  0xff6, 10, "SWAPSPACE2",		probe_swap1 },
1452  { "swsuspend", 0,  0xff6,  9, "S1SUSPEND",		probe_swap1 },
1453  { "swsuspend", 0,  0xff6,  9, "S2SUSPEND",		probe_swap1 },
1454  { "swsuspend", 0,  0xff6,  9, "ULSUSPEND",		probe_swap1 },
1455  { "swap",	 0, 0x1ff6, 10, "SWAP-SPACE",		probe_swap0 },
1456  { "swap",	 0, 0x1ff6, 10, "SWAPSPACE2",		probe_swap1 },
1457  { "swsuspend", 0, 0x1ff6,  9, "S1SUSPEND",		probe_swap1 },
1458  { "swsuspend", 0, 0x1ff6,  9, "S2SUSPEND",		probe_swap1 },
1459  { "swsuspend", 0, 0x1ff6,  9, "ULSUSPEND",		probe_swap1 },
1460  { "swap",	 0, 0x3ff6, 10, "SWAP-SPACE",		probe_swap0 },
1461  { "swap",	 0, 0x3ff6, 10, "SWAPSPACE2",		probe_swap1 },
1462  { "swsuspend", 0, 0x3ff6,  9, "S1SUSPEND",		probe_swap1 },
1463  { "swsuspend", 0, 0x3ff6,  9, "S2SUSPEND",		probe_swap1 },
1464  { "swsuspend", 0, 0x3ff6,  9, "ULSUSPEND",		probe_swap1 },
1465  { "swap",	 0, 0x7ff6, 10, "SWAP-SPACE",		probe_swap0 },
1466  { "swap",	 0, 0x7ff6, 10, "SWAPSPACE2",		probe_swap1 },
1467  { "swsuspend", 0, 0x7ff6,  9, "S1SUSPEND",		probe_swap1 },
1468  { "swsuspend", 0, 0x7ff6,  9, "S2SUSPEND",		probe_swap1 },
1469  { "swsuspend", 0, 0x7ff6,  9, "ULSUSPEND",		probe_swap1 },
1470  { "swap",	 0, 0xfff6, 10, "SWAP-SPACE",		probe_swap0 },
1471  { "swap",	 0, 0xfff6, 10, "SWAPSPACE2",		probe_swap1 },
1472  { "swsuspend", 0, 0xfff6,  9, "S1SUSPEND",		probe_swap1 },
1473  { "swsuspend", 0, 0xfff6,  9, "S2SUSPEND",		probe_swap1 },
1474  { "swsuspend", 0, 0xfff6,  9, "ULSUSPEND",		probe_swap1 },
1475  { "ocfs",	 0,	 8,  9,	"OracleCFS",		probe_ocfs },
1476  { "ocfs2",	 1,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1477  { "ocfs2",	 2,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1478  { "ocfs2",	 4,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1479  { "ocfs2",	 8,	 0,  6,	"OCFSV2",		probe_ocfs2 },
1480  { "crypt_LUKS", 0,	 0,  6,	"LUKS\xba\xbe",		probe_luks },
1481  { "squashfs",	 0,	 0,  4,	"sqsh",			0 },
1482  { "squashfs",	 0,	 0,  4,	"hsqs",			0 },
1483  { "lvm2pv",	 0,  0x218,  8, "LVM2 001",		probe_lvm2 },
1484  { "lvm2pv",	 0,  0x018,  8, "LVM2 001",		probe_lvm2 },
1485  { "lvm2pv",	 1,  0x018,  8, "LVM2 001",		probe_lvm2 },
1486  { "lvm2pv",	 1,  0x218,  8, "LVM2 001",		probe_lvm2 },
1487  { "btrfs",	 64,  0x40,  8, "_BHRfS_M",		probe_btrfs },
1488  {   NULL,	 0,	 0,  0, NULL,			NULL }
1489};
1490
1491/*
1492 * Verify that the data in dev is consistent with what is on the actual
1493 * block device (using the devname field only).  Normally this will be
1494 * called when finding items in the cache, but for long running processes
1495 * is also desirable to revalidate an item before use.
1496 *
1497 * If we are unable to revalidate the data, we return the old data and
1498 * do not set the BLKID_BID_FL_VERIFIED flag on it.
1499 */
1500blkid_dev blkid_verify(blkid_cache cache, blkid_dev dev)
1501{
1502	struct blkid_magic *id;
1503	struct blkid_probe probe;
1504	blkid_tag_iterate iter;
1505	unsigned char *buf;
1506	const char *type, *value;
1507	struct stat st;
1508	time_t now;
1509	double diff;
1510	int idx;
1511
1512	if (!dev)
1513		return NULL;
1514
1515	now = time(0);
1516	diff = difftime(now, dev->bid_time);
1517
1518	if (stat(dev->bid_name, &st) < 0) {
1519		DBG(DEBUG_PROBE,
1520		    printf("blkid_verify: error %s (%d) while "
1521			   "trying to stat %s\n", strerror(errno), errno,
1522			   dev->bid_name));
1523	open_err:
1524		if ((errno == EPERM) || (errno == EACCES) || (errno == ENOENT)) {
1525			/* We don't have read permission, just return cache data. */
1526			DBG(DEBUG_PROBE, printf("returning unverified data for %s\n",
1527						dev->bid_name));
1528			return dev;
1529		}
1530		blkid_free_dev(dev);
1531		return NULL;
1532	}
1533
1534	if ((now >= dev->bid_time) &&
1535	    (st.st_mtime <= dev->bid_time) &&
1536	    ((diff < BLKID_PROBE_MIN) ||
1537	     (dev->bid_flags & BLKID_BID_FL_VERIFIED &&
1538	      diff < BLKID_PROBE_INTERVAL)))
1539		return dev;
1540
1541	DBG(DEBUG_PROBE,
1542	    printf("need to revalidate %s (cache time %lu, stat time %lu,\n\t"
1543		   "time since last check %lu)\n",
1544		   dev->bid_name, (unsigned long)dev->bid_time,
1545		   (unsigned long)st.st_mtime, (unsigned long)diff));
1546
1547	if ((probe.fd = open(dev->bid_name, O_RDONLY)) < 0) {
1548		DBG(DEBUG_PROBE, printf("blkid_verify: error %s (%d) while "
1549					"opening %s\n", strerror(errno), errno,
1550					dev->bid_name));
1551		goto open_err;
1552	}
1553
1554	probe.cache = cache;
1555	probe.dev = dev;
1556	probe.sbbuf = 0;
1557	probe.buf = 0;
1558	probe.buf_max = 0;
1559
1560	/*
1561	 * Iterate over the type array.  If we already know the type,
1562	 * then try that first.  If it doesn't work, then blow away
1563	 * the type information, and try again.
1564	 *
1565	 */
1566try_again:
1567	type = 0;
1568	if (!dev->bid_type || !strcmp(dev->bid_type, "mdraid")) {
1569		uuid_t	uuid;
1570
1571		if (check_mdraid(probe.fd, uuid) == 0) {
1572			set_uuid(dev, uuid, 0);
1573			type = "mdraid";
1574			goto found_type;
1575		}
1576	}
1577	for (id = type_array; id->bim_type; id++) {
1578		if (dev->bid_type &&
1579		    strcmp(id->bim_type, dev->bid_type))
1580			continue;
1581
1582		idx = id->bim_kboff + (id->bim_sboff >> 10);
1583		buf = get_buffer(&probe, idx << 10, 1024);
1584		if (!buf)
1585			continue;
1586
1587		if (memcmp(id->bim_magic, buf + (id->bim_sboff & 0x3ff),
1588			   id->bim_len))
1589			continue;
1590
1591		if ((id->bim_probe == NULL) ||
1592		    (id->bim_probe(&probe, id, buf) == 0)) {
1593			type = id->bim_type;
1594			goto found_type;
1595		}
1596	}
1597
1598	if (!id->bim_type && dev->bid_type) {
1599		/*
1600		 * Zap the device filesystem information and try again
1601		 */
1602		DBG(DEBUG_PROBE,
1603		    printf("previous fs type %s not valid, "
1604			   "trying full probe\n", dev->bid_type));
1605		iter = blkid_tag_iterate_begin(dev);
1606		while (blkid_tag_next(iter, &type, &value) == 0)
1607			blkid_set_tag(dev, type, 0, 0);
1608		blkid_tag_iterate_end(iter);
1609		goto try_again;
1610	}
1611
1612	if (!dev->bid_type) {
1613		blkid_free_dev(dev);
1614		dev = 0;
1615		goto found_type;
1616	}
1617
1618found_type:
1619	if (dev && type) {
1620		dev->bid_devno = st.st_rdev;
1621		dev->bid_time = time(0);
1622		dev->bid_flags |= BLKID_BID_FL_VERIFIED;
1623		cache->bic_flags |= BLKID_BIC_FL_CHANGED;
1624
1625		blkid_set_tag(dev, "TYPE", type, 0);
1626
1627		DBG(DEBUG_PROBE, printf("%s: devno 0x%04llx, type %s\n",
1628			   dev->bid_name, (long long)st.st_rdev, type));
1629	}
1630
1631	free(probe.sbbuf);
1632	free(probe.buf);
1633	if (probe.fd >= 0)
1634		close(probe.fd);
1635
1636	return dev;
1637}
1638
1639int blkid_known_fstype(const char *fstype)
1640{
1641	struct blkid_magic *id;
1642
1643	for (id = type_array; id->bim_type; id++) {
1644		if (strcmp(fstype, id->bim_type) == 0)
1645			return 1;
1646	}
1647	return 0;
1648}
1649
1650#ifdef TEST_PROGRAM
1651int main(int argc, char **argv)
1652{
1653	blkid_dev dev;
1654	blkid_cache cache;
1655	int ret;
1656
1657	if (argc != 2) {
1658		fprintf(stderr, "Usage: %s device\n"
1659			"Probe a single device to determine type\n", argv[0]);
1660		exit(1);
1661	}
1662	if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
1663		fprintf(stderr, "%s: error creating cache (%d)\n",
1664			argv[0], ret);
1665		exit(1);
1666	}
1667	dev = blkid_get_dev(cache, argv[1], BLKID_DEV_NORMAL);
1668	if (!dev) {
1669		printf("%s: %s has an unsupported type\n", argv[0], argv[1]);
1670		return (1);
1671	}
1672	printf("TYPE='%s'\n", dev->bid_type ? dev->bid_type : "(null)");
1673	if (dev->bid_label)
1674		printf("LABEL='%s'\n", dev->bid_label);
1675	if (dev->bid_uuid)
1676		printf("UUID='%s'\n", dev->bid_uuid);
1677
1678	blkid_free_dev(dev);
1679	return (0);
1680}
1681#endif
1682