aboutsummaryrefslogtreecommitdiff
path: root/util-linux/mount.c
blob: 3a241540e66d123a404bc7d0320b996bf5e355da (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
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
/* vi: set sw=4 ts=4: */
/*
 * Mini mount implementation for busybox
 *
 * Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * 3/21/1999	Charles P. Wright <cpwright@cpwright.com>
 *		searches through fstab when -a is passed
 *		will try mounting stuff with all fses when passed -t auto
 *
 * 1999-04-17	Dave Cinege...Rewrote -t auto. Fixed ro mtab.
 *
 * 1999-10-07	Erik Andersen <andersen@codepoet.org>.
 *              Rewrite of a lot of code. Removed mtab usage (I plan on
 *              putting it back as a compile-time option some time),
 *              major adjustments to option parsing, and some serious
 *              dieting all around.
 *
 * 1999-11-06	mtab suppport is back - andersee
 *
 * 2000-01-12   Ben Collins <bcollins@debian.org>, Borrowed utils-linux's
 *              mount to add loop support.
 *
 * 2000-04-30	Dave Cinege <dcinege@psychosis.com>
 *		Rewrote fstab while loop and lower mount section. Can now do
 *		single mounts from fstab. Can override fstab options for single
 *		mount. Common mount_one call for single mounts and 'all'. Fixed
 *		mtab updating and stale entries. Removed 'remount' default.
 *
 */

#include <limits.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <mntent.h>
#include <ctype.h>
#include "busybox.h"

#ifdef CONFIG_NFSMOUNT
#if defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
#error "You need to build uClibc with UCLIBC_HAS_RPC for busybox mount with NFS support to compile."
#endif
#endif

enum {
	MS_MGC_VAL = 0xc0ed0000,	/* Magic number indicatng "new" flags */
	MS_RDONLY = 1,		/* Mount read-only */
	MS_NOSUID = 2,		/* Ignore suid and sgid bits */
	MS_NODEV = 4,		/* Disallow access to device special files */
	MS_NOEXEC = 8,		/* Disallow program execution */
	MS_SYNCHRONOUS = 16,	/* Writes are synced at once */
	MS_REMOUNT = 32,	/* Alter flags of a mounted FS */
	MS_MANDLOCK = 64,	/* Allow mandatory locks on an FS */
	S_QUOTA = 128,		/* Quota initialized for file/directory/symlink */
	S_APPEND = 256,		/* Append-only file */
	S_IMMUTABLE = 512,	/* Immutable file */
	MS_NOATIME = 1024,	/* Do not update access times. */
	MS_NODIRATIME = 2048,	/* Do not update directory access times */
	MS_BIND = 4096,		/* Use the new linux 2.4.x "mount --bind" feature */
};


#if defined CONFIG_FEATURE_MOUNT_LOOP
#include <fcntl.h>
#include <sys/ioctl.h>
static int use_loop = FALSE;
#endif

extern int mount(__const char *__special_file, __const char *__dir,
				 __const char *__fstype, unsigned long int __rwflag,
				 __const void *__data);
extern int umount(__const char *__special_file);
extern int umount2(__const char *__special_file, int __flags);

extern int sysfs(int option, unsigned int fs_index, char *buf);

struct mount_options {
	const char *name;
	unsigned long and;
	unsigned long or;
};

static const struct mount_options mount_options[] = {
	{"async", ~MS_SYNCHRONOUS, 0},
	{"atime", ~0, ~MS_NOATIME},
	{"defaults", ~0, 0},
	{"noauto", ~0, 0},
	{"dev", ~MS_NODEV, 0},
	{"diratime", ~0, ~MS_NODIRATIME},
	{"exec", ~MS_NOEXEC, 0},
	{"noatime", ~0, MS_NOATIME},
	{"nodev", ~0, MS_NODEV},
	{"nodiratime", ~0, MS_NODIRATIME},
	{"noexec", ~0, MS_NOEXEC},
	{"nosuid", ~0, MS_NOSUID},
	{"remount", ~0, MS_REMOUNT},
	{"ro", ~0, MS_RDONLY},
	{"rw", ~MS_RDONLY, 0},
	{"suid", ~MS_NOSUID, 0},
	{"sync", ~0, MS_SYNCHRONOUS},
	{"bind", ~0, MS_BIND},
	{0, 0, 0}
};

static int
do_mount(char *specialfile, char *dir, char *filesystemtype, long flags,
		 void *string_flags, int useMtab, int fakeIt, char *mtab_opts,
		 int mount_all)
{
	int status = 0;

#if defined CONFIG_FEATURE_MOUNT_LOOP
	char *lofile = NULL;
#endif

	if (!fakeIt) {
#if defined CONFIG_FEATURE_MOUNT_LOOP
		if (use_loop == TRUE) {
			int loro = flags & MS_RDONLY;

			lofile = specialfile;

			specialfile = find_unused_loop_device();
			if (specialfile == NULL) {
				bb_error_msg_and_die("Could not find a spare loop device");
			}
			if (set_loop(specialfile, lofile, 0, &loro)) {
				bb_error_msg_and_die("Could not setup loop device");
			}
			if (!(flags & MS_RDONLY) && loro) {	/* loop is ro, but wanted rw */
				bb_error_msg("WARNING: loop device is read-only");
				flags |= MS_RDONLY;
			}
		}
#endif
		status = mount(specialfile, dir, filesystemtype, flags, string_flags);
		if (status < 0 && errno == EROFS) {
			bb_error_msg("%s is write-protected, mounting read-only",
					  specialfile);
			status = mount(specialfile, dir, filesystemtype, flags |=
						   MS_RDONLY, string_flags);
		}
		/* Don't whine about already mounted filesystems when mounting all. */
		if (status < 0 && errno == EBUSY && mount_all) {
			return TRUE;
		}
	}


	/* If the mount was sucessful, do anything needed, then return TRUE */
	if (status == 0 || fakeIt == TRUE) {

#if defined CONFIG_FEATURE_MTAB_SUPPORT
		if (useMtab) {
			erase_mtab(specialfile);	/* Clean any stale entries */
			write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
		}
#endif
		return (TRUE);
	}

	/* Bummer.  mount failed.  Clean up */
#if defined CONFIG_FEATURE_MOUNT_LOOP
	if (lofile != NULL) {
		del_loop(specialfile);
	}
#endif

	if (errno == EPERM) {
		bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
	}

	return (FALSE);
}


static void paste_str(char **s1, const char *s2)
{
	*s1 = xrealloc(*s1, strlen(*s1) + strlen(s2) + 1);
	strcat(*s1, s2);
}

/* Seperate standard mount options from the nonstandard string options */
static void parse_mount_options(char *options, int *flags, char **strflags)
{
	while (options) {
		int gotone = FALSE;
		char *comma = strchr(options, ',');
		const struct mount_options *f = mount_options;

		if (comma) {
			*comma = '\0';
		}

		while (f->name != 0) {
			if (strcasecmp(f->name, options) == 0) {

				*flags &= f->and;
				*flags |= f->or;
				gotone = TRUE;
				break;
			}
			f++;
		}
#if defined CONFIG_FEATURE_MOUNT_LOOP
		if (!strcasecmp("loop", options)) {	/* loop device support */
			use_loop = TRUE;
			gotone = TRUE;
		}
#endif
		if (!gotone) {
			if (**strflags) {
				/* have previous parsed options */
				paste_str(strflags, ",");
			}
			paste_str(strflags, options);
		}
		if (comma) {
			*comma = ',';
			options = ++comma;
		} else {
			break;
		}
	}
}

static int mount_one(char *blockDevice, char *directory, char *filesystemType,
					 unsigned long flags, char *string_flags, int useMtab,
					 int fakeIt, char *mtab_opts, int whineOnErrors,
					 int mount_all)
{
	int status = 0;
	if (strcmp(filesystemType, "auto") == 0) {
		char buf[255];
		FILE *f;
		int read_proc = 0;

		f = fopen("/etc/filesystems", "r");

		if (f) {
			while (fgets(buf, sizeof(buf), f)) {
				if (*buf == '*') {
					read_proc = 1;
				} else if (*buf == '#') {
					continue;
				} else {
					filesystemType = buf;

					/* Add NULL termination to each line */
					while (*filesystemType && !isspace(*filesystemType)) {
						filesystemType++;
					}
					*filesystemType = '\0';

					filesystemType = buf;

					if (bb_strlen(filesystemType)) {
						status = do_mount(blockDevice, directory, filesystemType,
									 flags | MS_MGC_VAL, string_flags,
									 useMtab, fakeIt, mtab_opts, mount_all);
						if (status) {
							break;
						}
					}

				}
			}
			fclose(f);
		} else {
			read_proc = 1;
		}

		if (read_proc && !status) {

			f = bb_xfopen("/proc/filesystems", "r");

			while (fgets(buf, sizeof(buf), f) != NULL) {
				filesystemType = buf;
				if (*filesystemType == '\t') {	/* Not a nodev filesystem */

					/* Add NULL termination to each line */
					while (*filesystemType && *filesystemType != '\n') {
						filesystemType++;
					}
					*filesystemType = '\0';

					filesystemType = buf;
					filesystemType++;	/* hop past tab */

					status = do_mount(blockDevice, directory, filesystemType,
								 flags | MS_MGC_VAL, string_flags, useMtab,
								 fakeIt, mtab_opts, mount_all);
					if (status) {
						break;
					}
				}
			}
			fclose(f);
		}
	} else {
		status = do_mount(blockDevice, directory, filesystemType,
					 flags | MS_MGC_VAL, string_flags, useMtab, fakeIt,
					 mtab_opts, mount_all);
	}

	if (!status) {
		if (whineOnErrors) {
			bb_perror_msg("Mounting %s on %s failed", blockDevice, directory);
		}
		return (FALSE);
	}
	return (TRUE);
}

static void show_mounts(char *onlytype)
{
	FILE *mountTable = setmntent(bb_path_mtab_file, "r");

	if (mountTable) {
		struct mntent *m;

		while ((m = getmntent(mountTable)) != 0) {
			char *blockDevice = m->mnt_fsname;

			if (strcmp(blockDevice, "rootfs") == 0) {
				continue;
			} else if (strcmp(blockDevice, "/dev/root") == 0) {
				blockDevice = find_real_root_device_name(blockDevice);
			}
			if (!onlytype || (strcmp(m->mnt_type, onlytype) == 0)) {
				printf("%s on %s type %s (%s)\n", blockDevice, m->mnt_dir,
					   m->mnt_type, m->mnt_opts);
			}
#ifdef CONFIG_FEATURE_CLEAN_UP
			if (blockDevice != m->mnt_fsname) {
				free(blockDevice);
			}
#endif
		}
		endmntent(mountTable);
	} else {
		bb_perror_msg_and_die(bb_path_mtab_file);
	}
	exit(EXIT_SUCCESS);
}

extern int mount_main(int argc, char **argv)
{
	struct stat statbuf;
	char *string_flags = bb_xstrdup("");
	char *extra_opts;
	int flags = 0;
	char *filesystemType = "auto";
	int got_filesystemType = 0;
	char *device = xmalloc(PATH_MAX);
	char *directory = xmalloc(PATH_MAX);
	struct mntent *m = NULL;
	int all = FALSE;
	int fakeIt = FALSE;
	int useMtab = TRUE;
	int rc = EXIT_FAILURE;
	FILE *f = 0;
	int opt;

	/* Parse options */
	while ((opt = getopt(argc, argv, "o:rt:wafnv")) > 0) {
		switch (opt) {
		case 'o':
			parse_mount_options(optarg, &flags, &string_flags);
			break;
		case 'r':
			flags |= MS_RDONLY;
			break;
		case 't':
			filesystemType = optarg;
			got_filesystemType = 1;
			break;
		case 'w':
			flags &= ~MS_RDONLY;
			break;
		case 'a':
			all = TRUE;
			break;
		case 'f':
			fakeIt = TRUE;
			break;
		case 'n':
#ifdef CONFIG_FEATURE_MTAB_SUPPORT
			useMtab = FALSE;
#endif
			break;
		case 'v':
			break;		/* ignore -v */
		}
	}

	if (!all && (optind == argc)) {
		show_mounts(got_filesystemType ? filesystemType : NULL);
	}

	if (optind < argc) {
		/* if device is a filename get its real path */
		if (stat(argv[optind], &statbuf) == 0) {
			char *tmp = bb_simplify_path(argv[optind]);

			safe_strncpy(device, tmp, PATH_MAX);
		} else {
			safe_strncpy(device, argv[optind], PATH_MAX);
		}
	}

	if (optind + 1 < argc)
		directory = bb_simplify_path(argv[optind + 1]);

	if (all || optind + 1 == argc) {
		f = setmntent("/etc/fstab", "r");

		if (f == NULL)
			bb_perror_msg_and_die("\nCannot read /etc/fstab");

		while ((m = getmntent(f)) != NULL) {
			if (!all && (optind + 1 == argc)
				&& ((strcmp(device, m->mnt_fsname) != 0)
					&& (strcmp(device, m->mnt_dir) != 0))) {
				continue;
			}

			if (all && (	/* If we're mounting 'all' */
						   (strstr(m->mnt_opts, "noauto")) ||	/* and the file system isn't noauto, */
						   (strstr(m->mnt_type, "swap")))) /* and isn't swap, then mount it */
			{
				continue;
			}

			if (all || flags == 0) {	/* Allow single mount to override fstab flags */
				flags = 0;
				string_flags[0] = 0;
				parse_mount_options(m->mnt_opts, &flags, &string_flags);
			}

			strcpy(device, m->mnt_fsname);
			strcpy(directory, m->mnt_dir);
			filesystemType = bb_xstrdup(m->mnt_type);
		  singlemount:
			extra_opts = string_flags;
			rc = EXIT_SUCCESS;
#ifdef CONFIG_NFSMOUNT
			if (strchr(device, ':') != NULL) {
				filesystemType = "nfs";
				if (nfsmount
					(device, directory, &flags, &extra_opts, &string_flags,
					 1)) {
					bb_perror_msg("nfsmount failed");
					rc = EXIT_FAILURE;
				}
			}
#endif
			if (!mount_one
				(device, directory, filesystemType, flags, string_flags,
				 useMtab, fakeIt, extra_opts, TRUE, all)) {
				rc = EXIT_FAILURE;
			}
			if (!all) {
				break;
			}
		}
		if (f) {
			endmntent(f);
		}
		if (!all && f && m == NULL) {
			fprintf(stderr, "Can't find %s in /etc/fstab\n", device);
		}
		return rc;
	}

	goto singlemount;
}