probe.c revision 30dd2622353b9fde462c9112fb0c863620a3bf91
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 <sys/types.h>
22#ifdef HAVE_SYS_STAT_H
23#include <sys/stat.h>
24#endif
25#ifdef HAVE_SYS_MKDEV_H
26#include <sys/mkdev.h>
27#endif
28#ifdef HAVE_ERRNO_H
29#include <errno.h>
30#endif
31#include "blkidP.h"
32#include "uuid/uuid.h"
33#include "probe.h"
34
35static int figure_label_len(const unsigned char *label, int len)
36{
37	const unsigned char *end = label + len - 1;
38
39	while ((*end == ' ' || *end == 0) && end >= label)
40		--end;
41	if (end >= label) {
42		label = label;
43		return end - label + 1;
44	}
45	return 0;
46}
47
48static unsigned char *get_buffer(struct blkid_probe *pr,
49			  blkid_loff_t off, size_t len)
50{
51	ssize_t		ret_read;
52	unsigned char	*newbuf;
53
54	if (off + len <= SB_BUFFER_SIZE) {
55		if (!pr->sbbuf) {
56			pr->sbbuf = malloc(SB_BUFFER_SIZE);
57			if (!pr->sbbuf)
58				return NULL;
59			if (lseek(pr->fd, 0, SEEK_SET) < 0)
60				return NULL;
61			ret_read = read(pr->fd, pr->sbbuf, SB_BUFFER_SIZE);
62			if (ret_read < 0)
63				ret_read = 0;
64			pr->sb_valid = ret_read;
65		}
66		if (off+len > pr->sb_valid)
67			return NULL;
68		return pr->sbbuf + off;
69	} else {
70		if (len > pr->buf_max) {
71			newbuf = realloc(pr->buf, len);
72			if (newbuf == NULL)
73				return NULL;
74			pr->buf = newbuf;
75			pr->buf_max = len;
76		}
77		if (blkid_llseek(pr->fd, off, SEEK_SET) < 0)
78			return NULL;
79		ret_read = read(pr->fd, pr->buf, len);
80		if (ret_read != (ssize_t) len)
81			return NULL;
82		return pr->buf;
83	}
84}
85
86
87/*
88 * This is a special case code to check for an MDRAID device.  We do
89 * this special since it requires checking for a superblock at the end
90 * of the device.
91 */
92static int check_mdraid(int fd, unsigned char *ret_uuid)
93{
94	struct mdp_superblock_s *md;
95	blkid_loff_t		offset;
96	char			buf[4096];
97
98	if (fd < 0)
99		return -BLKID_ERR_PARAM;
100
101	offset = (blkid_get_dev_size(fd) & ~((blkid_loff_t)65535)) - 65536;
102
103	if (blkid_llseek(fd, offset, 0) < 0 ||
104	    read(fd, buf, 4096) != 4096)
105		return -BLKID_ERR_IO;
106
107	/* Check for magic number */
108	if (memcmp("\251+N\374", buf, 4) && memcmp("\374N+\251", buf, 4))
109		return -BLKID_ERR_PARAM;
110
111	if (!ret_uuid)
112		return 0;
113	*ret_uuid = 0;
114
115	/* The MD UUID is not contiguous in the superblock, make it so */
116	md = (struct mdp_superblock_s *)buf;
117	if (md->set_uuid0 || md->set_uuid1 || md->set_uuid2 || md->set_uuid3) {
118		memcpy(ret_uuid, &md->set_uuid0, 4);
119		memcpy(ret_uuid + 4, &md->set_uuid1, 12);
120	}
121	return 0;
122}
123
124static void set_uuid(blkid_dev dev, uuid_t uuid, char *tag)
125{
126	char	str[37];
127
128	if (!uuid_is_null(uuid)) {
129		uuid_unparse(uuid, str);
130		blkid_set_tag(dev, tag ? tag : "UUID", str, sizeof(str));
131	}
132}
133
134static void get_ext2_info(blkid_dev dev, unsigned char *buf)
135{
136	struct ext2_super_block *es = (struct ext2_super_block *) buf;
137	const char *label = 0;
138
139	DBG(DEBUG_PROBE, printf("ext2_sb.compat = %08X:%08X:%08X\n",
140		   blkid_le32(es->s_feature_compat),
141		   blkid_le32(es->s_feature_incompat),
142		   blkid_le32(es->s_feature_ro_compat)));
143
144	if (strlen(es->s_volume_name))
145		label = es->s_volume_name;
146	blkid_set_tag(dev, "LABEL", label, sizeof(es->s_volume_name));
147
148	set_uuid(dev, es->s_uuid, 0);
149}
150
151static int probe_ext3(struct blkid_probe *probe,
152		      struct blkid_magic *id __BLKID_ATTR((unused)),
153		      unsigned char *buf)
154{
155	struct ext2_super_block *es;
156	es = (struct ext2_super_block *)buf;
157
158	/* Distinguish between jbd and ext2/3 fs */
159	if (blkid_le32(es->s_feature_incompat) &
160	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
161		return -BLKID_ERR_PARAM;
162
163	/* Distinguish between ext3 and ext2 */
164	if (!(blkid_le32(es->s_feature_compat) &
165	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
166		return -BLKID_ERR_PARAM;
167
168	get_ext2_info(probe->dev, buf);
169
170	if ((es->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL) &&
171	    !uuid_is_null(es->s_journal_uuid))
172		set_uuid(probe->dev, es->s_journal_uuid, "EXT_JOURNAL");
173
174	blkid_set_tag(probe->dev, "SEC_TYPE", "ext2", sizeof("ext2"));
175
176	return 0;
177}
178
179static int probe_ext2(struct blkid_probe *probe,
180		      struct blkid_magic *id __BLKID_ATTR((unused)),
181		      unsigned char *buf)
182{
183	struct ext2_super_block *es;
184
185	es = (struct ext2_super_block *)buf;
186
187	/* Distinguish between jbd and ext2/3 fs */
188	if (blkid_le32(es->s_feature_incompat) &
189	    EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)
190		return -BLKID_ERR_PARAM;
191
192	/* Distinguish between ext3 and ext2 */
193	if ((blkid_le32(es->s_feature_compat) &
194	      EXT3_FEATURE_COMPAT_HAS_JOURNAL))
195		return -BLKID_ERR_PARAM;
196
197	get_ext2_info(probe->dev, buf);
198
199	return 0;
200}
201
202static int probe_jbd(struct blkid_probe *probe,
203		     struct blkid_magic *id __BLKID_ATTR((unused)),
204		     unsigned char *buf)
205{
206	struct ext2_super_block *es = (struct ext2_super_block *) buf;
207
208	if (!(blkid_le32(es->s_feature_incompat) &
209	      EXT3_FEATURE_INCOMPAT_JOURNAL_DEV))
210		return -BLKID_ERR_PARAM;
211
212	get_ext2_info(probe->dev, buf);
213
214	return 0;
215}
216
217#define FAT_ATTR_VOLUME_ID		0x08
218#define FAT_ATTR_DIR			0x10
219#define FAT_ATTR_LONG_NAME		0x0f
220#define FAT_ATTR_MASK			0x3f
221#define FAT_ENTRY_FREE			0xe5
222
223static char *no_name = "NO NAME    ";
224
225static unsigned char *search_fat_label(struct vfat_dir_entry *dir, int count)
226{
227	int i;
228
229	for (i = 0; i < count; i++) {
230		if (dir[i].name[0] == 0x00)
231			break;
232
233		if ((dir[i].name[0] == FAT_ENTRY_FREE) ||
234		    (dir[i].cluster_high != 0 || dir[i].cluster_low != 0) ||
235		    ((dir[i].attr & FAT_ATTR_MASK) == FAT_ATTR_LONG_NAME))
236			continue;
237
238		if ((dir[i].attr & (FAT_ATTR_VOLUME_ID | FAT_ATTR_DIR)) ==
239		    FAT_ATTR_VOLUME_ID) {
240			return dir[i].name;
241		}
242	}
243	return 0;
244}
245
246/* FAT label extraction from the root directory taken from Kay
247 * Sievers's volume_id library */
248static int probe_fat(struct blkid_probe *probe,
249		      struct blkid_magic *id __BLKID_ATTR((unused)),
250		      unsigned char *buf)
251{
252	struct vfat_super_block *vs = (struct vfat_super_block *) buf;
253	struct msdos_super_block *ms = (struct msdos_super_block *) buf;
254	struct vfat_dir_entry *dir;
255	char serno[10];
256	const unsigned char *label = 0, *vol_label = 0, *tmp;
257	unsigned char	*vol_serno;
258	int label_len = 0, maxloop = 100;
259	__u16 sector_size, dir_entries, reserved;
260	__u32 sect_count, fat_size, dir_size, cluster_count, fat_length;
261	__u32 buf_size, start_data_sect, next, root_start, root_dir_entries;
262
263	/* sector size check */
264	tmp = (unsigned char *)&ms->ms_sector_size;
265	sector_size = tmp[0] + (tmp[1] << 8);
266	if (sector_size != 0x200 && sector_size != 0x400 &&
267	    sector_size != 0x800 && sector_size != 0x1000)
268		return 1;
269
270	tmp = (unsigned char *)&ms->ms_dir_entries;
271	dir_entries = tmp[0] + (tmp[1] << 8);
272	reserved =  blkid_le16(ms->ms_reserved);
273	tmp = (unsigned char *)&ms->ms_sectors;
274	sect_count = tmp[0] + (tmp[1] << 8);
275	if (sect_count == 0)
276		sect_count = blkid_le32(ms->ms_total_sect);
277
278	fat_length = blkid_le16(ms->ms_fat_length);
279	if (fat_length == 0)
280		fat_length = blkid_le32(vs->vs_fat32_length);
281
282	fat_size = fat_length * ms->ms_fats;
283	dir_size = ((dir_entries * sizeof(struct vfat_dir_entry)) +
284			(sector_size-1)) / sector_size;
285
286	cluster_count = sect_count - (reserved + fat_size + dir_size);
287	cluster_count /= ms->ms_cluster_size;
288
289	if (cluster_count > FAT32_MAX)
290		return 1;
291
292	if (ms->ms_fat_length) {
293		/* the label may be an attribute in the root directory */
294		root_start = (reserved + fat_size) * sector_size;
295		root_dir_entries = vs->vs_dir_entries[0] +
296			(vs->vs_dir_entries[1] << 8);
297
298		buf_size = root_dir_entries * sizeof(struct vfat_dir_entry);
299		dir = (struct vfat_dir_entry *) get_buffer(probe, root_start,
300							   buf_size);
301		if (dir)
302			vol_label = search_fat_label(dir, root_dir_entries);
303
304		if (!vol_label || !memcmp(vol_label, no_name, 11))
305			vol_label = ms->ms_label;
306		vol_serno = ms->ms_serno;
307
308		blkid_set_tag(probe->dev, "SEC_TYPE", "msdos",
309			      sizeof("msdos"));
310	} else {
311		/* Search the FAT32 root dir for the label attribute */
312		buf_size = vs->vs_cluster_size * sector_size;
313		start_data_sect = reserved + fat_size;
314
315		next = blkid_le32(vs->vs_root_cluster);
316		while (next && --maxloop) {
317			__u32 next_sect_off;
318			__u64 next_off, fat_entry_off;
319			int count;
320
321			next_sect_off = (next - 2) * vs->vs_cluster_size;
322			next_off = (start_data_sect + next_sect_off) *
323				sector_size;
324
325			dir = (struct vfat_dir_entry *)
326				get_buffer(probe, next_off, buf_size);
327			if (dir == NULL)
328				break;
329
330			count = buf_size / sizeof(struct vfat_dir_entry);
331
332			vol_label = search_fat_label(dir, count);
333			if (vol_label)
334				break;
335
336			/* get FAT entry */
337			fat_entry_off = (reserved * sector_size) +
338				(next * sizeof(__u32));
339			buf = get_buffer(probe, fat_entry_off, buf_size);
340			if (buf == NULL)
341				break;
342
343			/* set next cluster */
344			next = blkid_le32(*((__u32 *) buf) & 0x0fffffff);
345		}
346
347		if (!vol_label || !memcmp(vol_label, no_name, 11))
348			vol_label = vs->vs_label;
349		vol_serno = vs->vs_serno;
350	}
351
352	if (vol_label && memcmp(vol_label, no_name, 11)) {
353		if ((label_len = figure_label_len(vol_label, 11)))
354			label = vol_label;
355	}
356
357	/* We can't just print them as %04X, because they are unaligned */
358	sprintf(serno, "%02X%02X-%02X%02X", vol_serno[3], vol_serno[2],
359		vol_serno[1], vol_serno[0]);
360
361	blkid_set_tag(probe->dev, "LABEL", (const char *) label, label_len);
362	blkid_set_tag(probe->dev, "UUID", serno, sizeof(serno)-1);
363
364	return 0;
365}
366
367/*
368 * The FAT filesystem could be without a magic string in superblock
369 * (e.g. old floppies).  This heuristic for FAT detection is inspired
370 * by http://vrfy.org/projects/volume_id/ and Linux kernel.
371 * [7-Jul-2005, Karel Zak <kzak@redhat.com>]
372 */
373static int probe_fat_nomagic(struct blkid_probe *probe,
374			     struct blkid_magic *id __BLKID_ATTR((unused)),
375			     unsigned char *buf)
376{
377	struct vfat_super_block *vs;
378
379	vs = (struct vfat_super_block *)buf;
380
381	/* heads check */
382	if (vs->vs_heads == 0)
383		return 1;
384
385	/* cluster size check*/
386	if (vs->vs_cluster_size == 0 ||
387	    (vs->vs_cluster_size & (vs->vs_cluster_size-1)))
388		return 1;
389
390	/* media check */
391	if (vs->vs_media < 0xf8 && vs->vs_media != 0xf0)
392		return 1;
393
394	/* fat counts(Linux kernel expects at least 1 FAT table) */
395	if (!vs->vs_fats)
396		return 1;
397
398	return probe_fat(probe, id, buf);
399}
400
401static int probe_ntfs(struct blkid_probe *probe,
402		      struct blkid_magic *id __BLKID_ATTR((unused)),
403		      unsigned char *buf)
404{
405	struct ntfs_super_block *ns;
406	struct master_file_table_record *mft;
407	struct file_attribute *attr;
408	char		uuid_str[17], label_str[129], *cp;
409	int		bytes_per_sector, sectors_per_cluster;
410	int		mft_record_size, attr_off, attr_len;
411	unsigned int	i, attr_type, val_len;
412	int		val_off;
413	__u64		nr_clusters;
414	blkid_loff_t off;
415	unsigned char *buf_mft, *val;
416
417	ns = (struct ntfs_super_block *) buf;
418
419	bytes_per_sector = ns->bios_parameter_block[0] +
420		(ns->bios_parameter_block[1]  << 8);
421	sectors_per_cluster = ns->bios_parameter_block[2];
422
423	if ((bytes_per_sector < 512) || (sectors_per_cluster == 0))
424		return 1;
425
426	if (ns->cluster_per_mft_record < 0)
427		mft_record_size = 1 << (0-ns->cluster_per_mft_record);
428	else
429		mft_record_size = ns->cluster_per_mft_record *
430			sectors_per_cluster * bytes_per_sector;
431	nr_clusters = blkid_le64(ns->number_of_sectors) / sectors_per_cluster;
432
433	if ((blkid_le64(ns->mft_cluster_location) > nr_clusters) ||
434	    (blkid_le64(ns->mft_mirror_cluster_location) > nr_clusters))
435		return 1;
436
437	off = blkid_le64(ns->mft_mirror_cluster_location) *
438		bytes_per_sector * sectors_per_cluster;
439
440	buf_mft = get_buffer(probe, off, mft_record_size);
441	if (!buf_mft)
442		return 1;
443
444	if (memcmp(buf_mft, "FILE", 4))
445		return 1;
446
447	off = blkid_le64(ns->mft_cluster_location) * bytes_per_sector *
448		sectors_per_cluster;
449
450	buf_mft = get_buffer(probe, off, mft_record_size);
451	if (!buf_mft)
452		return 1;
453
454	if (memcmp(buf_mft, "FILE", 4))
455		return 1;
456
457	off += MFT_RECORD_VOLUME * mft_record_size;
458
459	buf_mft = get_buffer(probe, off, mft_record_size);
460	if (!buf_mft)
461		return 1;
462
463	if (memcmp(buf_mft, "FILE", 4))
464		return 1;
465
466	mft = (struct master_file_table_record *) buf_mft;
467
468	attr_off = blkid_le16(mft->attrs_offset);
469	label_str[0] = 0;
470
471	while (1) {
472		attr = (struct file_attribute *) (buf_mft + attr_off);
473		attr_len = blkid_le16(attr->len);
474		attr_type = blkid_le32(attr->type);
475		val_off = blkid_le16(attr->value_offset);
476		val_len = blkid_le32(attr->value_len);
477
478		attr_off += attr_len;
479
480		if ((attr_off > mft_record_size) ||
481		    (attr_len == 0))
482			break;
483
484		if (attr_type == MFT_RECORD_ATTR_END)
485			break;
486
487		if (attr_type == MFT_RECORD_ATTR_VOLUME_NAME) {
488			if (val_len > sizeof(label_str))
489				val_len = sizeof(label_str)-1;
490
491			for (i=0, cp=label_str; i < val_len; i+=2,cp++) {
492				val = ((__u8 *) attr) + val_off + i;
493				*cp = val[0];
494				if (val[1])
495					*cp = '?';
496			}
497			*cp = 0;
498		}
499	}
500
501	sprintf(uuid_str, "%llX", blkid_le64(ns->volume_serial));
502	blkid_set_tag(probe->dev, "UUID", uuid_str, 0);
503	if (label_str[0])
504		blkid_set_tag(probe->dev, "LABEL", label_str, 0);
505	return 0;
506}
507
508
509static int probe_xfs(struct blkid_probe *probe,
510		     struct blkid_magic *id __BLKID_ATTR((unused)),
511		     unsigned char *buf)
512{
513	struct xfs_super_block *xs;
514	const char *label = 0;
515
516	xs = (struct xfs_super_block *)buf;
517
518	if (strlen(xs->xs_fname))
519		label = xs->xs_fname;
520	blkid_set_tag(probe->dev, "LABEL", label, sizeof(xs->xs_fname));
521	set_uuid(probe->dev, xs->xs_uuid, 0);
522	return 0;
523}
524
525static int probe_reiserfs(struct blkid_probe *probe,
526			  struct blkid_magic *id, unsigned char *buf)
527{
528	struct reiserfs_super_block *rs = (struct reiserfs_super_block *) buf;
529	unsigned int blocksize;
530	const char *label = 0;
531
532	blocksize = blkid_le16(rs->rs_blocksize);
533
534	/* If the superblock is inside the journal, we have the wrong one */
535	if (id->bim_kboff/(blocksize>>10) > blkid_le32(rs->rs_journal_block))
536		return -BLKID_ERR_BIG;
537
538	/* LABEL/UUID are only valid for later versions of Reiserfs v3.6. */
539	if (id->bim_magic[6] == '2' || id->bim_magic[6] == '3') {
540		if (strlen(rs->rs_label))
541			label = rs->rs_label;
542		set_uuid(probe->dev, rs->rs_uuid, 0);
543	}
544	blkid_set_tag(probe->dev, "LABEL", label, sizeof(rs->rs_label));
545
546	return 0;
547}
548
549static int probe_reiserfs4(struct blkid_probe *probe,
550			   struct blkid_magic *id __BLKID_ATTR((unused)),
551			   unsigned char *buf)
552{
553	struct reiser4_super_block *rs4 = (struct reiser4_super_block *) buf;
554	const unsigned char *label = 0;
555
556	if (strlen((char *) rs4->rs4_label))
557		label = rs4->rs4_label;
558	set_uuid(probe->dev, rs4->rs4_uuid, 0);
559	blkid_set_tag(probe->dev, "LABEL", (const char *) label,
560		      sizeof(rs4->rs4_label));
561
562	return 0;
563}
564
565static int probe_jfs(struct blkid_probe *probe,
566		     struct blkid_magic *id __BLKID_ATTR((unused)),
567		     unsigned char *buf)
568{
569	struct jfs_super_block *js;
570	const char *label = 0;
571
572	js = (struct jfs_super_block *)buf;
573
574	if (strlen((char *) js->js_label))
575		label = (char *) js->js_label;
576	blkid_set_tag(probe->dev, "LABEL", label, sizeof(js->js_label));
577	set_uuid(probe->dev, js->js_uuid, 0);
578	return 0;
579}
580
581static int probe_luks(struct blkid_probe *probe,
582		       struct blkid_magic *id __BLKID_ATTR((unused)),
583		       unsigned char *buf)
584{
585	unsigned char uuid[40];
586	/* 168 is the offset to the 40 character uuid:
587	 * http://luks.endorphin.org/LUKS-on-disk-format.pdf */
588	strncpy(uuid, buf+168, 40);
589	blkid_set_tag(probe->dev, "UUID", uuid, sizeof(uuid));
590	return 0;
591}
592
593static int probe_romfs(struct blkid_probe *probe,
594		       struct blkid_magic *id __BLKID_ATTR((unused)),
595		       unsigned char *buf)
596{
597	struct romfs_super_block *ros;
598	const char *label = 0;
599
600	ros = (struct romfs_super_block *)buf;
601
602	if (strlen((char *) ros->ros_volume))
603		label = (char *) ros->ros_volume;
604	blkid_set_tag(probe->dev, "LABEL", label, 0);
605	return 0;
606}
607
608static int probe_cramfs(struct blkid_probe *probe,
609			struct blkid_magic *id __BLKID_ATTR((unused)),
610			unsigned char *buf)
611{
612	struct cramfs_super_block *csb;
613	const char *label = 0;
614
615	csb = (struct cramfs_super_block *)buf;
616
617	if (strlen((char *) csb->name))
618		label = (char *) csb->name;
619	blkid_set_tag(probe->dev, "LABEL", label, 0);
620	return 0;
621}
622
623static int probe_swap0(struct blkid_probe *probe,
624		       struct blkid_magic *id __BLKID_ATTR((unused)),
625		       unsigned char *buf __BLKID_ATTR((unused)))
626{
627	blkid_set_tag(probe->dev, "UUID", 0, 0);
628	blkid_set_tag(probe->dev, "LABEL", 0, 0);
629	return 0;
630}
631
632static int probe_swap1(struct blkid_probe *probe,
633		       struct blkid_magic *id __BLKID_ATTR((unused)),
634		       unsigned char *buf __BLKID_ATTR((unused)))
635{
636	struct swap_id_block *sws;
637
638	probe_swap0(probe, id, buf);
639	/*
640	 * Version 1 swap headers are always located at offset of 1024
641	 * bytes, although the swap signature itself is located at the
642	 * end of the page (which may vary depending on hardware
643	 * pagesize).
644	 */
645	sws = (struct swap_id_block *) get_buffer(probe, 1024, 1024);
646	if (!sws)
647		return 1;
648
649	/* arbitrary sanity check.. is there any garbage down there? */
650	if (sws->sws_pad[32] == 0 && sws->sws_pad[33] == 0)  {
651		if (sws->sws_volume[0])
652			blkid_set_tag(probe->dev, "LABEL", sws->sws_volume,
653				      sizeof(sws->sws_volume));
654		if (sws->sws_uuid[0])
655			set_uuid(probe->dev, sws->sws_uuid, 0);
656	}
657	return 0;
658}
659
660static int probe_iso9660(struct blkid_probe *probe,
661			 struct blkid_magic *id __BLKID_ATTR((unused)),
662			 unsigned char *buf)
663{
664	struct iso_volume_descriptor *iso;
665	const unsigned char *label;
666
667	iso = (struct iso_volume_descriptor *) buf;
668	label = iso->volume_id;
669
670	blkid_set_tag(probe->dev, "LABEL", (const char *) label,
671		      figure_label_len(label, 32));
672	return 0;
673}
674
675
676static const char
677*udf_magic[] = { "BEA01", "BOOT2", "CD001", "CDW02", "NSR02",
678		 "NSR03", "TEA01", 0 };
679
680static int probe_udf(struct blkid_probe *probe,
681		     struct blkid_magic *id __BLKID_ATTR((unused)),
682		     unsigned char *buf __BLKID_ATTR((unused)))
683{
684	int j, bs;
685	struct iso_volume_descriptor *isosb;
686	const char ** m;
687
688	/* determine the block size by scanning in 2K increments
689	   (block sizes larger than 2K will be null padded) */
690	for (bs = 1; bs < 16; bs++) {
691		isosb = (struct iso_volume_descriptor *)
692			get_buffer(probe, bs*2048+32768, sizeof(isosb));
693		if (!isosb)
694			return 1;
695		if (isosb->vd_id[0])
696			break;
697	}
698
699	/* Scan up to another 64 blocks looking for additional VSD's */
700	for (j = 1; j < 64; j++) {
701		if (j > 1) {
702			isosb = (struct iso_volume_descriptor *)
703				get_buffer(probe, j*bs*2048+32768,
704					   sizeof(isosb));
705			if (!isosb)
706				return 1;
707		}
708		/* If we find NSR0x then call it udf:
709		   NSR01 for UDF 1.00
710		   NSR02 for UDF 1.50
711		   NSR03 for UDF 2.00 */
712		if (!memcmp(isosb->vd_id, "NSR0", 4))
713			return 0;
714		for (m = udf_magic; *m; m++)
715			if (!memcmp(*m, isosb->vd_id, 5))
716				break;
717		if (*m == 0)
718			return 1;
719	}
720	return 1;
721}
722
723static int probe_ocfs(struct blkid_probe *probe,
724		      struct blkid_magic *id __BLKID_ATTR((unused)),
725		      unsigned char *buf)
726{
727	struct ocfs_volume_header ovh;
728	struct ocfs_volume_label ovl;
729	__u32 major;
730
731	memcpy(&ovh, buf, sizeof(ovh));
732	memcpy(&ovl, buf+512, sizeof(ovl));
733
734	major = ocfsmajor(ovh);
735	if (major == 1)
736		blkid_set_tag(probe->dev,"SEC_TYPE","ocfs1",sizeof("ocfs1"));
737	else if (major >= 9)
738		blkid_set_tag(probe->dev,"SEC_TYPE","ntocfs",sizeof("ntocfs"));
739
740	blkid_set_tag(probe->dev, "LABEL", ovl.label, ocfslabellen(ovl));
741	blkid_set_tag(probe->dev, "MOUNT", ovh.mount, ocfsmountlen(ovh));
742	set_uuid(probe->dev, ovl.vol_id, 0);
743	return 0;
744}
745
746static int probe_ocfs2(struct blkid_probe *probe,
747		       struct blkid_magic *id __BLKID_ATTR((unused)),
748		       unsigned char *buf)
749{
750	struct ocfs2_super_block *osb;
751
752	osb = (struct ocfs2_super_block *)buf;
753
754	blkid_set_tag(probe->dev, "LABEL", osb->s_label, sizeof(osb->s_label));
755	set_uuid(probe->dev, osb->s_uuid, 0);
756	return 0;
757}
758
759static int probe_oracleasm(struct blkid_probe *probe,
760			   struct blkid_magic *id __BLKID_ATTR((unused)),
761			   unsigned char *buf)
762{
763	struct oracle_asm_disk_label *dl;
764
765	dl = (struct oracle_asm_disk_label *)buf;
766
767	blkid_set_tag(probe->dev, "LABEL", dl->dl_id, sizeof(dl->dl_id));
768	return 0;
769}
770
771static int probe_gfs(struct blkid_probe *probe,
772		     struct blkid_magic *id __BLKID_ATTR((unused)),
773		     unsigned char *buf)
774{
775	struct gfs2_sb *sbd;
776	const char *label = 0;
777
778	sbd = (struct gfs2_sb *)buf;
779
780	if (blkid_be32(sbd->sb_fs_format) == GFS_FORMAT_FS &&
781	    blkid_be32(sbd->sb_multihost_format) == GFS_FORMAT_MULTI)
782	{
783		blkid_set_tag(probe->dev, "UUID", 0, 0);
784
785		if (strlen(sbd->sb_locktable))
786			label = sbd->sb_locktable;
787		blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
788		return 0;
789	}
790	return 1;
791}
792
793static int probe_gfs2(struct blkid_probe *probe,
794		     struct blkid_magic *id __BLKID_ATTR((unused)),
795		     unsigned char *buf)
796{
797	struct gfs2_sb *sbd;
798	const char *label = 0;
799
800	sbd = (struct gfs2_sb *)buf;
801
802	if (blkid_be32(sbd->sb_fs_format) == GFS2_FORMAT_FS &&
803	    blkid_be32(sbd->sb_multihost_format) == GFS2_FORMAT_MULTI)
804	{
805		blkid_set_tag(probe->dev, "UUID", 0, 0);
806
807		if (strlen(sbd->sb_locktable))
808			label = sbd->sb_locktable;
809		blkid_set_tag(probe->dev, "LABEL", label, sizeof(sbd->sb_locktable));
810		return 0;
811	}
812	return 1;
813}
814
815/*
816 * BLKID_BLK_OFFS is at least as large as the highest bim_kboff defined
817 * in the type_array table below + bim_kbalign.
818 *
819 * When probing for a lot of magics, we handle everything in 1kB buffers so
820 * that we don't have to worry about reading each combination of block sizes.
821 */
822#define BLKID_BLK_OFFS	64	/* currently reiserfs */
823
824/*
825 * Various filesystem magics that we can check for.  Note that kboff and
826 * sboff are in kilobytes and bytes respectively.  All magics are in
827 * byte strings so we don't worry about endian issues.
828 */
829static struct blkid_magic type_array[] = {
830/*  type     kboff   sboff len  magic			probe */
831  { "oracleasm", 0,	32,  8, "ORCLDISK",		probe_oracleasm },
832  { "ntfs",	 0,	 3,  8, "NTFS    ",		probe_ntfs },
833  { "jbd",	 1,   0x38,  2, "\123\357",		probe_jbd },
834  { "ext3",	 1,   0x38,  2, "\123\357",		probe_ext3 },
835  { "ext2",	 1,   0x38,  2, "\123\357",		probe_ext2 },
836  { "reiserfs",	 8,   0x34,  8, "ReIsErFs",		probe_reiserfs },
837  { "reiserfs", 64,   0x34,  9, "ReIsEr2Fs",		probe_reiserfs },
838  { "reiserfs", 64,   0x34,  9, "ReIsEr3Fs",		probe_reiserfs },
839  { "reiserfs", 64,   0x34,  8, "ReIsErFs",		probe_reiserfs },
840  { "reiserfs",	 8,	20,  8, "ReIsErFs",		probe_reiserfs },
841  { "reiser4",  64,	 0,  7, "ReIsEr4",		probe_reiserfs4 },
842  { "gfs2",     64,      0,  4, "\x01\x16\x19\x70",     probe_gfs2 },
843  { "gfs",      64,      0,  4, "\x01\x16\x19\x70",     probe_gfs },
844  { "vfat",      0,   0x52,  5, "MSWIN",                probe_fat },
845  { "vfat",      0,   0x52,  8, "FAT32   ",             probe_fat },
846  { "vfat",      0,   0x36,  5, "MSDOS",                probe_fat },
847  { "vfat",      0,   0x36,  8, "FAT16   ",             probe_fat },
848  { "vfat",      0,   0x36,  8, "FAT12   ",             probe_fat },
849  { "vfat",      0,      0,  2, "\353\220",             probe_fat_nomagic },
850  { "vfat",      0,      0,  1, "\351",                 probe_fat_nomagic },
851  { "minix",     1,   0x10,  2, "\177\023",             0 },
852  { "minix",     1,   0x10,  2, "\217\023",             0 },
853  { "minix",	 1,   0x10,  2, "\150\044",		0 },
854  { "minix",	 1,   0x10,  2, "\170\044",		0 },
855  { "vxfs",	 1,	 0,  4, "\365\374\001\245",	0 },
856  { "xfs",	 0,	 0,  4, "XFSB",			probe_xfs },
857  { "romfs",	 0,	 0,  8, "-rom1fs-",		probe_romfs },
858  { "bfs",	 0,	 0,  4, "\316\372\173\033",	0 },
859  { "cramfs",	 0,	 0,  4, "E=\315\050",		probe_cramfs },
860  { "qnx4",	 0,	 4,  6, "QNX4FS",		0 },
861  { "udf",	32,	 1,  5, "BEA01",		probe_udf },
862  { "udf",	32,	 1,  5, "BOOT2",		probe_udf },
863  { "udf",	32,	 1,  5, "CD001",		probe_udf },
864  { "udf",	32,	 1,  5, "CDW02",		probe_udf },
865  { "udf",	32,	 1,  5, "NSR02",		probe_udf },
866  { "udf",	32,	 1,  5, "NSR03",		probe_udf },
867  { "udf",	32,	 1,  5, "TEA01",		probe_udf },
868  { "iso9660",	32,	 1,  5, "CD001",		probe_iso9660 },
869  { "iso9660",	32,	 9,  5, "CDROM",		probe_iso9660 },
870  { "jfs",	32,	 0,  4, "JFS1",			probe_jfs },
871  { "hfs",	 1,	 0,  2, "BD",			0 },
872  { "ufs",	 8,  0x55c,  4, "T\031\001\000",	0 },
873  { "hpfs",	 8,	 0,  4, "I\350\225\371",	0 },
874  { "sysv",	 0,  0x3f8,  4, "\020~\030\375",	0 },
875  { "swap",	 0,  0xff6, 10, "SWAP-SPACE",		probe_swap0 },
876  { "swap",	 0,  0xff6, 10, "SWAPSPACE2",		probe_swap1 },
877  { "swsuspend", 0,  0xff6,  9, "S1SUSPEND",		probe_swap1 },
878  { "swsuspend", 0,  0xff6,  9, "S2SUSPEND",		probe_swap1 },
879  { "swap",	 0, 0x1ff6, 10, "SWAP-SPACE",		probe_swap0 },
880  { "swap",	 0, 0x1ff6, 10, "SWAPSPACE2",		probe_swap1 },
881  { "swsuspend", 0, 0x1ff6,  9, "S1SUSPEND",		probe_swap1 },
882  { "swsuspend", 0, 0x1ff6,  9, "S2SUSPEND",		probe_swap1 },
883  { "swap",	 0, 0x3ff6, 10, "SWAP-SPACE",		probe_swap0 },
884  { "swap",	 0, 0x3ff6, 10, "SWAPSPACE2",		probe_swap1 },
885  { "swsuspend", 0, 0x3ff6,  9, "S1SUSPEND",		probe_swap1 },
886  { "swsuspend", 0, 0x3ff6,  9, "S2SUSPEND",		probe_swap1 },
887  { "swap",	 0, 0x7ff6, 10, "SWAP-SPACE",		probe_swap0 },
888  { "swap",	 0, 0x7ff6, 10, "SWAPSPACE2",		probe_swap1 },
889  { "swsuspend", 0, 0x7ff6,  9, "S1SUSPEND",		probe_swap1 },
890  { "swsuspend", 0, 0x7ff6,  9, "S2SUSPEND",		probe_swap1 },
891  { "swap",	 0, 0xfff6, 10, "SWAP-SPACE",		probe_swap0 },
892  { "swap",	 0, 0xfff6, 10, "SWAPSPACE2",		probe_swap1 },
893  { "swsuspend", 0, 0xfff6,  9, "S1SUSPEND",		probe_swap1 },
894  { "swsuspend", 0, 0xfff6,  9, "S2SUSPEND",		probe_swap1 },
895  { "ocfs",	 0,	 8,  9,	"OracleCFS",		probe_ocfs },
896  { "ocfs2",	 1,	 0,  6,	"OCFSV2",		probe_ocfs2 },
897  { "ocfs2",	 2,	 0,  6,	"OCFSV2",		probe_ocfs2 },
898  { "ocfs2",	 4,	 0,  6,	"OCFSV2",		probe_ocfs2 },
899  { "ocfs2",	 8,	 0,  6,	"OCFSV2",		probe_ocfs2 },
900  { "crypt_LUKS", 0,	 0,  6,	"LUKS\xba\xbe",		probe_luks },
901  {   NULL,	 0,	 0,  0, NULL,			NULL }
902};
903
904/*
905 * Verify that the data in dev is consistent with what is on the actual
906 * block device (using the devname field only).  Normally this will be
907 * called when finding items in the cache, but for long running processes
908 * is also desirable to revalidate an item before use.
909 *
910 * If we are unable to revalidate the data, we return the old data and
911 * do not set the BLKID_BID_FL_VERIFIED flag on it.
912 */
913blkid_dev blkid_verify(blkid_cache cache, blkid_dev dev)
914{
915	struct blkid_magic *id;
916	struct blkid_probe probe;
917	blkid_tag_iterate iter;
918	unsigned char *buf;
919	const char *type, *value;
920	struct stat st;
921	time_t diff, now;
922	int idx;
923
924	if (!dev)
925		return NULL;
926
927	now = time(0);
928	diff = now - dev->bid_time;
929
930	if ((now > dev->bid_time) && (diff > 0) &&
931	    ((diff < BLKID_PROBE_MIN) ||
932	     (dev->bid_flags & BLKID_BID_FL_VERIFIED &&
933	      diff < BLKID_PROBE_INTERVAL)))
934		return dev;
935
936	DBG(DEBUG_PROBE,
937	    printf("need to revalidate %s (time since last check %llu)\n",
938		   dev->bid_name, (unsigned long long)diff));
939
940	if (((probe.fd = open(dev->bid_name, O_RDONLY)) < 0) ||
941	    (fstat(probe.fd, &st) < 0)) {
942		if (probe.fd >= 0) close(probe.fd);
943		if (errno == ENXIO || errno == ENODEV || errno == ENOENT) {
944			blkid_free_dev(dev);
945			return NULL;
946		}
947		/* We don't have read permission, just return cache data. */
948		DBG(DEBUG_PROBE,
949		    printf("returning unverified data for %s\n",
950			   dev->bid_name));
951		return dev;
952	}
953
954	probe.cache = cache;
955	probe.dev = dev;
956	probe.sbbuf = 0;
957	probe.buf = 0;
958	probe.buf_max = 0;
959
960	/*
961	 * Iterate over the type array.  If we already know the type,
962	 * then try that first.  If it doesn't work, then blow away
963	 * the type information, and try again.
964	 *
965	 */
966try_again:
967	type = 0;
968	if (!dev->bid_type || !strcmp(dev->bid_type, "mdraid")) {
969		uuid_t	uuid;
970
971		if (check_mdraid(probe.fd, uuid) == 0) {
972			set_uuid(dev, uuid, 0);
973			type = "mdraid";
974			goto found_type;
975		}
976	}
977	for (id = type_array; id->bim_type; id++) {
978		if (dev->bid_type &&
979		    strcmp(id->bim_type, dev->bid_type))
980			continue;
981
982		idx = id->bim_kboff + (id->bim_sboff >> 10);
983		buf = get_buffer(&probe, idx << 10, 1024);
984		if (!buf)
985			continue;
986
987		if (memcmp(id->bim_magic, buf + (id->bim_sboff&0x3ff),
988			   id->bim_len))
989			continue;
990
991		if ((id->bim_probe == NULL) ||
992		    (id->bim_probe(&probe, id, buf) == 0)) {
993			type = id->bim_type;
994			goto found_type;
995		}
996	}
997
998	if (!id->bim_type && dev->bid_type) {
999		/*
1000		 * Zap the device filesystem information and try again
1001		 */
1002		iter = blkid_tag_iterate_begin(dev);
1003		while (blkid_tag_next(iter, &type, &value) == 0)
1004			blkid_set_tag(dev, type, 0, 0);
1005		blkid_tag_iterate_end(iter);
1006		goto try_again;
1007	}
1008
1009	if (!dev->bid_type) {
1010		blkid_free_dev(dev);
1011		dev = 0;
1012		goto found_type;
1013	}
1014
1015found_type:
1016	if (dev && type) {
1017		dev->bid_devno = st.st_rdev;
1018		dev->bid_time = time(0);
1019		dev->bid_flags |= BLKID_BID_FL_VERIFIED;
1020		cache->bic_flags |= BLKID_BIC_FL_CHANGED;
1021
1022		blkid_set_tag(dev, "TYPE", type, 0);
1023
1024		DBG(DEBUG_PROBE, printf("%s: devno 0x%04llx, type %s\n",
1025			   dev->bid_name, (long long)st.st_rdev, type));
1026	}
1027
1028	if (probe.sbbuf)
1029		free(probe.sbbuf);
1030	if (probe.buf)
1031		free(probe.buf);
1032	if (probe.fd >= 0)
1033		close(probe.fd);
1034
1035	return dev;
1036}
1037
1038int blkid_known_fstype(const char *fstype)
1039{
1040	struct blkid_magic *id;
1041
1042	for (id = type_array; id->bim_type; id++) {
1043		if (strcmp(fstype, id->bim_type) == 0)
1044			return 1;
1045	}
1046	return 0;
1047}
1048
1049#ifdef TEST_PROGRAM
1050int main(int argc, char **argv)
1051{
1052	blkid_dev dev;
1053	blkid_cache cache;
1054	int ret;
1055
1056	if (argc != 2) {
1057		fprintf(stderr, "Usage: %s device\n"
1058			"Probe a single device to determine type\n", argv[0]);
1059		exit(1);
1060	}
1061	if ((ret = blkid_get_cache(&cache, "/dev/null")) != 0) {
1062		fprintf(stderr, "%s: error creating cache (%d)\n",
1063			argv[0], ret);
1064		exit(1);
1065	}
1066	dev = blkid_get_dev(cache, argv[1], BLKID_DEV_NORMAL);
1067	if (!dev) {
1068		printf("%s: %s has an unsupported type\n", argv[0], argv[1]);
1069		return (1);
1070	}
1071	printf("TYPE='%s'\n", dev->bid_type ? dev->bid_type : "(null)");
1072	if (dev->bid_label)
1073		printf("LABEL='%s'\n", dev->bid_label);
1074	if (dev->bid_uuid)
1075		printf("UUID='%s'\n", dev->bid_uuid);
1076
1077	blkid_free_dev(dev);
1078	return (0);
1079}
1080#endif
1081