summaryrefslogtreecommitdiff
path: root/extras/volume_id/vol_id.c
blob: d8302bc22923ede0a52d345107b5682a66a1955e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
/*
 * vol_id - read filesystem label and uuid
 *
 * Copyright (C) 2005-2008 Kay Sievers <kay.sievers@vrfy.org>
 *
 *	This program is free software; you can redistribute it and/or modify it
 *	under the terms of the GNU General Public License as published by the
 *	Free Software Foundation version 2 of the License.
 * 
 *	This program is distributed in the hope that it will be useful, but
 *	WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *	General Public License for more details.
 * 
 *	You should have received a copy of the GNU General Public License along
 *	with this program; if not, write to the Free Software Foundation, Inc.,
 *	675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#ifndef _GNU_SOURCE
#define _GNU_SOURCE 1
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <pwd.h>
#include <grp.h>
#include <getopt.h>
#include <fcntl.h>
#include <sys/ioctl.h>

#include "../../udev/udev.h"
#include "lib/libvolume_id.h"

#define BLKGETSIZE64 _IOR(0x12,114,size_t)

static int debug;

static void log_fn(struct udev *udev, int priority,
		   const char *file, int line, const char *fn,
		   const char *format, va_list args)
{
	if (debug) {
		fprintf(stderr, "%s: ", fn != NULL ? fn : file);
		vfprintf(stderr, format, args);
	} else {
		vsyslog(priority, format, args);
	}
}

static void vid_log(int priority, const char *file, int line, const char *format, ...)
{
	va_list args;

	va_start(args, format);
	log_fn(NULL, priority, file, line, NULL, format, args);
	va_end(args);
	return;
}

static void set_str(char *to, const char *from, size_t count)
{
	size_t i, j, len;

	/* strip trailing whitespace */
	len = strnlen(from, count);
	while (len && isspace(from[len-1]))
		len--;

	/* strip leading whitespace */
	i = 0;
	while (isspace(from[i]) && (i < len))
		i++;

	j = 0;
	while (i < len) {
		/* substitute multiple whitespace */
		if (isspace(from[i])) {
			while (isspace(from[i]))
				i++;
			to[j++] = '_';
		}
		/* skip chars */
		if (from[i] == '/') {
			i++;
			continue;
		}
		to[j++] = from[i++];
	}
	to[j] = '\0';
}

static int all_probers(volume_id_probe_fn_t probe_fn,
		       struct volume_id *id, uint64_t off, uint64_t size,
		       void *data)
{
	const char *type;

	if (probe_fn(id, off, size) == 0)
		if (volume_id_get_type(id, &type))
			printf("%s\n", type);

	return 0;
}

int main(int argc, char *argv[])
{
	struct udev *udev;
	static const struct option options[] = {
		{ "label", 0, NULL, 'l' },
		{ "label-raw", 0, NULL, 'L' },
		{ "uuid", 0, NULL, 'u' },
		{ "type", 0, NULL, 't' },
		{ "export", 0, NULL, 'x' },
		{ "skip-raid", 0, NULL, 's' },
		{ "probe-all", 0, NULL, 'a' },
		{ "offset", 2, NULL, 'o' },
		{ "debug", 0, NULL, 'd' },
		{ "help", 0, NULL, 'h' },
		{}
	};

	enum print_type {
		PRINT_EXPORT,
		PRINT_TYPE,
		PRINT_LABEL,
		PRINT_UUID,
		PRINT_LABEL_RAW,
	} print = PRINT_EXPORT;

	struct volume_id *vid = NULL;
	char label_safe[256];
	char label_enc[256];
	char uuid_enc[256];
	uint64_t size;
	int skip_raid = 0;
	int probe_all = 0;
	uint64_t offset = 0;
	const char *node;
	int fd;
	const char *label, *uuid, *type, *type_version, *usage;
	int retval;
	int rc = 0;

	udev = udev_new();
	if (udev == NULL)
		goto exit;
	logging_init("vol_id");
	udev_set_log_fn(udev, log_fn);

	/* hook in our debug into libvolume_id */
	volume_id_log_fn = vid_log;

	while (1) {
		int option;

		option = getopt_long(argc, argv, "lLutxsaodh", options, NULL);
		if (option == -1)
			break;

		switch (option) {
		case 'd':
			debug = 1;
			if (udev_get_log_priority(udev) < LOG_INFO)
				udev_set_log_priority(udev, LOG_INFO);
			break;
		case 'l':
			print = PRINT_LABEL;
			break;
		case 'L':
			print = PRINT_LABEL_RAW;
			break;
		case 'u':
			print = PRINT_UUID;
			break;
		case 't':
			print = PRINT_TYPE;
			break;
		case 'x':
			print = PRINT_EXPORT;
			break;
		case 's':
			skip_raid = 1;
			break;
		case 'a':
			probe_all = 1;
			break;
		case 'o':
			if (optarg[0] != '\0')
				offset = strtoull(optarg, NULL, 0);
			break;
		case 'h':
			printf("Usage: vol_id [options] <device>\n"
			    " --export         export key/value pairs\n"
			    " --type           filesystem type\n"
			    " --label          filesystem label\n"
			    " --label-raw      raw label\n"
			    " --uuid           filesystem uuid\n"
			    " --skip-raid      don't probe for raid\n"
			    " --probe-all      find possibly conflicting signatures\n"
			    " --offset=<bytes> probe at the given offset\n"
			    " --debug          print debug output to stderr\n"
			    " --help\n\n");
			goto exit;
		default:
			retval = 1;
			goto exit;
		}
	}

	node = argv[optind];
	if (!node) {
		err(udev, "no device\n");
		fprintf(stderr, "no device\n");
		rc = 1;
		goto exit;
	}

	fd = open(node, O_RDONLY);
	if (fd < 0) {
		fprintf(stderr, "%s: error opening volume\n", node);
		rc = 2;
		goto exit;
	}

	vid = volume_id_open_fd(fd);
	if (vid == NULL) {
		rc = 2;
		goto exit;
	}

	if (ioctl(fd, BLKGETSIZE64, &size) != 0)
		size = 0;
	info(udev, "BLKGETSIZE64=%llu (%lluGB)\n", (unsigned long long)size, (unsigned long long)size >> 30);

	/* try to drop all privileges before reading disk content */
	if (getuid() == 0) {
		struct passwd *pw;

		pw = getpwnam("nobody");
		if (pw != NULL && pw->pw_uid > 0 && pw->pw_gid > 0) {
			if (setgroups(0, NULL) != 0 ||
			    setgid(pw->pw_gid) != 0 ||
			    setuid(pw->pw_uid) != 0)
				info(udev, "unable to drop privileges: %s\n\n", strerror(errno));
		}
	}

	if (probe_all) {
		volume_id_all_probers(all_probers, vid, offset, size, NULL);
		goto exit;
	}

	if (skip_raid)
		retval = volume_id_probe_filesystem(vid, offset, size);
	else
		retval = volume_id_probe_all(vid, offset, size);
	if (retval != 0) {
		fprintf(stderr, "%s: unknown volume type\n", node);
		rc = 4;
		goto exit;
	}

	if (!volume_id_get_label(vid, &label) ||
	    !volume_id_get_usage(vid, &usage) ||
	    !volume_id_get_type(vid, &type) ||
	    !volume_id_get_type_version(vid, &type_version) ||
	    !volume_id_get_uuid(vid, &uuid)) {
		rc = 4;
		goto exit;
	}

	set_str(label_safe, label, sizeof(label_safe));
	replace_chars(label_safe, ALLOWED_CHARS_INPUT);

	volume_id_encode_string(label, label_enc, sizeof(label_enc));
	volume_id_encode_string(uuid, uuid_enc, sizeof(uuid_enc));

	switch (print) {
	case PRINT_EXPORT:
		printf("ID_FS_USAGE=%s\n", usage);
		printf("ID_FS_TYPE=%s\n", type);
		printf("ID_FS_VERSION=%s\n", type_version);
		printf("ID_FS_UUID=%s\n", uuid);
		printf("ID_FS_UUID_ENC=%s\n", uuid_enc);
		printf("ID_FS_LABEL=%s\n", label);
		printf("ID_FS_LABEL_ENC=%s\n", label_enc);
		printf("ID_FS_LABEL_SAFE=%s\n", label_safe);
		break;
	case PRINT_TYPE:
		printf("%s\n", type);
		break;
	case PRINT_LABEL:
		if (label_safe[0] == '\0' || strcmp(usage, "raid") == 0) {
			rc = 3;
			goto exit;
		}
		printf("%s\n", label_safe);
		break;
	case PRINT_UUID:
		if (uuid_enc[0] == '\0' || strcmp(usage, "raid") == 0) {
			rc = 4;
			goto exit;
		}
		printf("%s\n", uuid_enc);
		break;
	case PRINT_LABEL_RAW:
		if (label[0] == '\0' || strcmp(usage, "raid") == 0) {
			rc = 3;
			goto exit;
		}
		printf("%s\n", label);
		break;
	}

exit:
	if (vid != NULL)
		volume_id_close(vid);
	udev_unref(udev);
	logging_close();
	return rc;
}