summaryrefslogtreecommitdiff
path: root/util-linux/mount.c
blob: 010757d1ec5dabb6b1447010ee4a0e7a0de7dbbd (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
/*
   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.
*/

#include "internal.h"
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <mntent.h>
#include <sys/mount.h>
#include <ctype.h>

const char	mount_usage[] = "mount\n"
"\t\tmount [flags] special-device directory\n"
"\n"
"Flags:\n"
"\t-a:\tMount all file systems in fstab.\n"
"\t-f:\t\"Fake\" mount. Add entry to mount table but don't mount it.\n"
"\t-n:\tDon't write a mount table entry.\n"
"\t-o option:\tOne of many filesystem options, listed below.\n"
"\t-r:\tMount the filesystem read-only.\n"
"\t-t filesystem-type:\tSpecify the filesystem type.\n"
"\t-w:\tMount for reading and writing (default).\n"
"\n"
"Options for use with the \"-o\" flag:\n"
"\tasync / sync:\tWrites are asynchronous / synchronous.\n"
"\tdev / nodev:\tAllow use of special device files / disallow them.\n"
"\texec / noexec:\tAllow use of executable files / disallow them.\n"
"\tsuid / nosuid:\tAllow set-user-id-root programs / disallow them.\n"
"\tremount: Re-mount a currently-mounted filesystem, changing its flags.\n"
"\tro / rw: Mount for read-only / read-write.\n"
"\t"
"There are EVEN MORE flags that are specific to each filesystem.\n"
"You'll have to see the written documentation for those.\n";

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

static const struct mount_options	mount_options[] = {
	{	"async",	~MS_SYNCHRONOUS,0		},
	{	"defaults",	~0,		0		},
	{	"dev",		~MS_NODEV,	0		},
	{	"exec",		~MS_NOEXEC,	0		},
	{	"nodev",	~0,		MS_NODEV	},
	{	"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	},
	{	0,		0,		0		}
};

static void
show_flags(unsigned long flags, char * buffer)
{
	const struct mount_options *	f = mount_options;
	while ( f->name ) {
		if ( flags & f->and ) {
			int	length = strlen(f->name);
			memcpy(buffer, f->name, length);
			buffer += length;
			*buffer++ = ',';
			*buffer = '\0';
		}
		f++;
	}
}

static void
one_option(
 char *			option
,unsigned long *	flags
,char *			data)
{
	const struct mount_options *	f = mount_options;

	while ( f->name != 0 ) {
		if ( strcasecmp(f->name, option) == 0 ) {
			*flags &= f->and;
			*flags |= f->or;
			return;
		}
		f++;
	}
	if ( *data ) {
		data += strlen(data);
		*data++ = ',';
	}
	strcpy(data, option);
}

static void
parse_mount_options(
 char *			options
,unsigned long *	flags
,char *			data)
{
	while ( *options ) {
		char * comma = strchr(options, ',');
		if ( comma )
			*comma = '\0';
		one_option(options, flags, data);
		if ( comma ) {
			*comma = ',';
			options = ++comma;
		}
		else
			break;
	}
}

int
mount_one(
 char *		blockDevice
,char *		directory
,char *		filesystemType
,unsigned long	flags
,char *		string_flags
,int		noMtab
,int		fake)
{
	int	error = 0;
	int 	status = 0;

	char	buf[255];
		
	if (!fake) {
		if (*filesystemType == 'a') { 			//Will fail on real FS starting with 'a'

			FILE	*f = fopen("/proc/filesystems", "r");

			if (f == NULL)	return 1;

			while (fgets(buf, sizeof(buf), f) != NULL) {
				filesystemType = buf;
				if (*filesystemType == '\t') {  // Not a nodev filesystem
					
					while (*filesystemType && *filesystemType != '\n')	filesystemType++;
					*filesystemType = '\0';
						
					filesystemType = buf;
					filesystemType++;	//hop past tab
					
					status = mount(blockDevice, directory, filesystemType,
							flags|MS_MGC_VAL ,string_flags);
					error = errno;

					if (status == 0) break;
				}
			}
			fclose(f);
		} else {	

			status = mount( blockDevice, directory, filesystemType,
					flags|MS_MGC_VAL ,string_flags);
			error = errno;
		}
	}

	if ( status == 0 ) {
		char *	s = &string_flags[strlen(string_flags)];
		FILE *	mountTable;
		if ( s != string_flags ) {
			*s++ = ',';
			show_flags(flags, s);
		}
		if ( !noMtab && (mountTable = setmntent("/etc/mtab", "a+")) ) {
			int	length = strlen(directory);
			struct mntent	m;

			if ( length > 1 && directory[length - 1] == '/' )
				directory[length - 1] = '\0';

			if ( filesystemType == 0 ) {
				struct mntent *	p
				 = findMountPoint(blockDevice, "/proc/mounts");

				if ( p && p->mnt_type )
					filesystemType = p->mnt_type;
			}
			m.mnt_fsname = blockDevice;
			m.mnt_dir = directory;
			m.mnt_type = filesystemType ? filesystemType : "default";
			
			if (*string_flags) {
				m.mnt_opts = string_flags;
			} else {
				if ( (flags | MS_RDONLY) == flags )
					m.mnt_opts = "ro";
				else	
					m.mnt_opts = "rw";
			}
			
			m.mnt_freq = 0;
			m.mnt_passno = 0;
			addmntent(mountTable, &m);
			endmntent(mountTable);
		}
		return 0;
	} else {
		fprintf(stderr, "Mount %s", blockDevice);
		if ( filesystemType && *filesystemType )
			fprintf(stderr, " (type %s)", filesystemType);

		fprintf(
		 stderr
		," on %s: "
		,directory);

		switch ( error ) {
		case EPERM:
			if (geteuid() == 0)
				fprintf(
				 stderr
				,"mount point %s is not a directory"
				,blockDevice);
			else
				fprintf(
				 stderr
				,"must be superuser to use mount");
			break;
		case EBUSY:
			fprintf(
			 stderr
			,"%s already mounted or %s busy"
			,blockDevice
			,directory);
			break;
		case ENOENT:
		{
			struct stat statbuf;
			if ( stat(directory, &statbuf) != 0 )
				fprintf(
				 stderr
				,"directory %s does not exist"
				,directory);
			else if ( stat(blockDevice, &statbuf) != 0 )
				fprintf(
				 stderr
				,"block device %s does not exist"
				,blockDevice);
			else
				fprintf(
				 stderr
				,"%s is not mounted on %s, but the mount table says it is."
				,blockDevice
				,directory);
			break;
		}
		case ENOTDIR:
			fprintf(
			 stderr
			,"%s is not a directory"
			,directory);
			break;
		case EINVAL:
			fprintf(
			 stderr
			,"wrong filesystem type, or bad superblock on %s"
			,blockDevice);
			break;
		case EMFILE:
			fprintf(stderr, "mount table full");
			break;
		case EIO:
			fprintf(
			 stderr
			,"I/O error reading %s"
			,blockDevice);
			break;
		case ENODEV:
		{
			FILE *	f = fopen("/proc/filesystems", "r");

			fprintf(
			 stderr
			,"filesystem type %s not in kernel.\n"
			,filesystemType);
			fprintf(stderr, "Do you need to load a module?\n");
			if ( f ) {
				char	buf[100];

				fprintf(
				 stderr
				,"Here are the filesystem types the kernel"
				 " can mount:\n");
				while ( fgets(buf, sizeof(buf), f) != 0 )
					fprintf(stderr, "\t%s", buf);
				fclose(f);
			}
			break;
		}
		case ENOTBLK:
			fprintf(
			 stderr
			,"%s is not a block device"
			,blockDevice);
			break;
		case ENXIO:
			fprintf(
			 stderr
			,"%s is not a valid block device"
			,blockDevice);
			break;
		default:
			fputs(strerror(errno), stderr);
		}
		putc('\n', stderr);
		return -1;
	}
}

extern int
mount_main(struct FileInfo * i, int argc, char * * argv)
{
	char	string_flags[1024];
	unsigned long	flags = 0;
	char *	filesystemType = "auto";
	int		fake = 0;
	int		noMtab = 0;
	int 		all = 0;
	
	*string_flags = '\0';

	if ( argc == 1 ) {
		FILE *	mountTable;
		if ( (mountTable = setmntent("/etc/mtab", "r")) ) {
			struct mntent * m;
			while ( (m = getmntent(mountTable)) != 0 ) {
				printf(
				 "%s on %s type %s (%s)\n"
				,m->mnt_fsname
				,m->mnt_dir
				,m->mnt_type
				,m->mnt_opts);
			}
			endmntent(mountTable);
		}
		return 0;
	}

	while ( argc >= 2 && argv[1][0] == '-' ) {
		switch ( argv[1][1] ) {
		case 'f':
			fake = 1;
			break;
		case 'n':
			noMtab = 1;
			break;
		case 'o':
			if ( argc < 3 ) {
				usage(mount_usage);
				return 1;
			}
			parse_mount_options(argv[2], &flags, string_flags);
			argc--;
			argv++;
			break;
		case 'r':
			flags |= MS_RDONLY;
			break;
		case 't':
			if ( argc < 3 ) {
				usage(mount_usage);
				return 1;
			}
			filesystemType = argv[2];
			argc--;
			argv++;
			break;
		case 'v':
			break;
		case 'w':
			flags &= ~MS_RDONLY;
			break;
		case 'a':
			all = 1;
			break;
		default:
			usage(mount_usage);
			return 1;
		}
		argc--;
		argv++;
	}

	if (all == 1) {
		struct 	mntent *m;
		FILE	*f = setmntent("/etc/fstab", "r");

		if (f == NULL)	{
			return 1;
		}

		// FIXME: Combine read routine (make new function) with unmount_all to save space.

		while ((m = getmntent(f)) != NULL) {	
			// If the file system isn't noauto, and isn't mounted on /, mount it
			if ((!strstr(m->mnt_opts, "noauto")) && (m->mnt_dir[1] != '\0') 
				&& !((m->mnt_type[0] == 's') && (m->mnt_type[1] == 'w')) 
				&& !((m->mnt_type[0] == 'n') && (m->mnt_type[1] == 'f'))) {
				mount_one(m->mnt_fsname, m->mnt_dir, m->mnt_type, flags, m->mnt_opts, noMtab, fake);	
			}
		}

		endmntent(f);
	} else {
		if ( argc >= 3 ) {
			if ( mount_one( argv[1], argv[2], filesystemType, flags, string_flags, noMtab, fake) == 0 )
				return 0;
			else
				return 1;
		} else {
			usage(mount_usage);
			return 1;
		}
	}
	return 0;
}