xref: /freebsd/sbin/mount/mount.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
1 /*-
2  * Copyright (c) 1980, 1989, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1980, 1989, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)mount.c	8.25 (Berkeley) 5/8/95";
43 #endif
44 static const char rcsid[] =
45 	"$Id$";
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 #include <sys/mount.h>
50 #include <sys/stat.h>
51 #include <sys/wait.h>
52 
53 #include <err.h>
54 #include <errno.h>
55 #include <fstab.h>
56 #include <pwd.h>
57 #include <signal.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <unistd.h>
62 
63 #include "extern.h"
64 #include "pathnames.h"
65 
66 int debug, fstab_style, verbose;
67 
68 char   *catopt __P((char *, const char *));
69 struct statfs
70        *getmntpt __P((const char *));
71 int	hasopt __P((const char *, const char *));
72 int	ismounted __P((struct fstab *, struct statfs *, int));
73 int	isremountable __P((const char *));
74 void	mangle __P((char *, int *, const char **));
75 int	mountfs __P((const char *, const char *, const char *,
76 			int, const char *, const char *));
77 void	prmount __P((struct statfs *));
78 void	putfsent __P((const struct statfs *));
79 void	usage __P((void));
80 
81 /* Map from mount options to printable formats. */
82 static struct opt {
83 	int o_opt;
84 	const char *o_name;
85 } optnames[] = {
86 	{ MNT_ASYNC,		"asynchronous" },
87 	{ MNT_EXPORTED,		"NFS exported" },
88 	{ MNT_LOCAL,		"local" },
89 	{ MNT_NOATIME,		"noatime" },
90 	{ MNT_NODEV,		"nodev" },
91 	{ MNT_NOEXEC,		"noexec" },
92 	{ MNT_NOSUID,		"nosuid" },
93 	{ MNT_NOSYMFOLLOW,	"nosymfollow" },
94 	{ MNT_QUOTA,		"with quotas" },
95 	{ MNT_RDONLY,		"read-only" },
96 	{ MNT_SYNCHRONOUS,	"synchronous" },
97 	{ MNT_UNION,		"union" },
98 	{ MNT_NOCLUSTERR,	"noclusterr" },
99 	{ MNT_NOCLUSTERW,	"noclusterw" },
100 	{ MNT_SUIDDIR,		"suiddir" },
101 	{ MNT_SOFTDEP,		"soft-updates" },
102 	{ NULL }
103 };
104 
105 /*
106  * List of VFS types that can be remounted without becoming mounted on top
107  * of each other.
108  * XXX Is this list correct?
109  */
110 static const char *
111 remountable_fs_names[] = {
112 	"ufs", "ffs", "lfs", "ext2fs",
113 	0
114 };
115 
116 int
117 main(argc, argv)
118 	int argc;
119 	char * const argv[];
120 {
121 	const char *mntfromname, **vfslist, *vfstype;
122 	struct fstab *fs;
123 	struct statfs *mntbuf;
124 	FILE *mountdfp;
125 	pid_t pid;
126 	int all, ch, i, init_flags, mntsize, rval;
127 	char *options;
128 
129 	all = init_flags = 0;
130 	options = NULL;
131 	vfslist = NULL;
132 	vfstype = "ufs";
133 	while ((ch = getopt(argc, argv, "adfo:prwt:uv")) != -1)
134 		switch (ch) {
135 		case 'a':
136 			all = 1;
137 			break;
138 		case 'd':
139 			debug = 1;
140 			break;
141 		case 'f':
142 			init_flags |= MNT_FORCE;
143 			break;
144 		case 'o':
145 			if (*optarg)
146 				options = catopt(options, optarg);
147 			break;
148 		case 'p':
149 			fstab_style = 1;
150 			verbose = 1;
151 			break;
152 		case 'r':
153 			init_flags |= MNT_RDONLY;
154 			break;
155 		case 't':
156 			if (vfslist != NULL)
157 				errx(1, "only one -t option may be specified");
158 			vfslist = makevfslist(optarg);
159 			vfstype = optarg;
160 			break;
161 		case 'u':
162 			init_flags |= MNT_UPDATE;
163 			break;
164 		case 'v':
165 			verbose = 1;
166 			break;
167 		case 'w':
168 			init_flags &= ~MNT_RDONLY;
169 			break;
170 		case '?':
171 		default:
172 			usage();
173 			/* NOTREACHED */
174 		}
175 	argc -= optind;
176 	argv += optind;
177 
178 #define	BADTYPE(type)							\
179 	(strcmp(type, FSTAB_RO) &&					\
180 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
181 
182 	rval = 0;
183 	switch (argc) {
184 	case 0:
185 		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
186 			err(1, "getmntinfo");
187 		if (all) {
188 			while ((fs = getfsent()) != NULL) {
189 				if (BADTYPE(fs->fs_type))
190 					continue;
191 				if (checkvfsname(fs->fs_vfstype, vfslist))
192 					continue;
193 				if (hasopt(fs->fs_mntops, "noauto"))
194 					continue;
195 				if (ismounted(fs, mntbuf, mntsize))
196 					continue;
197 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
198 				    fs->fs_file, init_flags, options,
199 				    fs->fs_mntops))
200 					rval = 1;
201 			}
202 		} else if (fstab_style) {
203 			for (i = 0; i < mntsize; i++) {
204 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
205 					continue;
206 				putfsent(&mntbuf[i]);
207 			}
208 		} else {
209 			for (i = 0; i < mntsize; i++) {
210 				if (checkvfsname(mntbuf[i].f_fstypename,
211 				    vfslist))
212 					continue;
213 				prmount(&mntbuf[i]);
214 			}
215 		}
216 		exit(rval);
217 	case 1:
218 		if (vfslist != NULL)
219 			usage();
220 
221 		if (init_flags & MNT_UPDATE) {
222 			if ((mntbuf = getmntpt(*argv)) == NULL)
223 				errx(1,
224 				    "unknown special file or file system %s",
225 				    *argv);
226 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL)
227 				mntfromname = fs->fs_spec;
228 			else
229 				mntfromname = mntbuf->f_mntfromname;
230 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
231 			    mntbuf->f_mntonname, init_flags, options, 0);
232 			break;
233 		}
234 		if ((fs = getfsfile(*argv)) == NULL &&
235 		    (fs = getfsspec(*argv)) == NULL)
236 			errx(1, "%s: unknown special file or file system",
237 			    *argv);
238 		if (BADTYPE(fs->fs_type))
239 			errx(1, "%s has unknown file system type",
240 			    *argv);
241 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
242 		    init_flags, options, fs->fs_mntops);
243 		break;
244 	case 2:
245 		/*
246 		 * If -t flag has not been specified, and spec contains either
247 		 * a ':' or a '@' then assume that an NFS filesystem is being
248 		 * specified ala Sun.
249 		 */
250 		if (vfslist == NULL && strpbrk(argv[0], ":@") != NULL)
251 			vfstype = "nfs";
252 		rval = mountfs(vfstype,
253 		    argv[0], argv[1], init_flags, options, NULL);
254 		break;
255 	default:
256 		usage();
257 		/* NOTREACHED */
258 	}
259 
260 	/*
261 	 * If the mount was successfully, and done by root, tell mountd the
262 	 * good news.  Pid checks are probably unnecessary, but don't hurt.
263 	 */
264 	if (rval == 0 && getuid() == 0 &&
265 	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
266 		if (fscanf(mountdfp, "%d", &pid) == 1 &&
267 		     pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
268 			err(1, "signal mountd");
269 		(void)fclose(mountdfp);
270 	}
271 
272 	exit(rval);
273 }
274 
275 int
276 ismounted(fs, mntbuf, mntsize)
277 	struct fstab *fs;
278 	struct statfs *mntbuf;
279 	int mntsize;
280 {
281 	int i;
282 
283 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
284 		/* the root file system can always be remounted */
285 		return (0);
286 
287 	for (i = mntsize - 1; i >= 0; --i)
288 		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
289 		    (!isremountable(fs->fs_vfstype) ||
290 		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
291 			return (1);
292 	return (0);
293 }
294 
295 int
296 isremountable(vfsname)
297 	const char *vfsname;
298 {
299 	const char **cp;
300 
301 	for (cp = remountable_fs_names; *cp; cp++)
302 		if (strcmp(*cp, vfsname) == 0)
303 			return (1);
304 	return (0);
305 }
306 
307 int
308 hasopt(mntopts, option)
309 	const char *mntopts, *option;
310 {
311 	int negative, found;
312 	char *opt, *optbuf;
313 
314 	if (option[0] == 'n' && option[1] == 'o') {
315 		negative = 1;
316 		option += 2;
317 	} else
318 		negative = 0;
319 	optbuf = strdup(mntopts);
320 	found = 0;
321 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
322 		if (opt[0] == 'n' && opt[1] == 'o') {
323 			if (!strcasecmp(opt + 2, option))
324 				found = negative;
325 		} else if (!strcasecmp(opt, option))
326 			found = !negative;
327 	}
328 	free(optbuf);
329 	return (found);
330 }
331 
332 int
333 mountfs(vfstype, spec, name, flags, options, mntopts)
334 	const char *vfstype, *spec, *name, *options, *mntopts;
335 	int flags;
336 {
337 	/* List of directories containing mount_xxx subcommands. */
338 	static const char *edirs[] = {
339 		_PATH_SBIN,
340 		_PATH_USRSBIN,
341 		NULL
342 	};
343 	const char *argv[100], **edir;
344 	struct stat sb;
345 	struct statfs sf;
346 	pid_t pid;
347 	int argc, i, status;
348 	char *optbuf, execname[MAXPATHLEN + 1], mntpath[MAXPATHLEN];
349 
350 #if __GNUC__
351 	(void)&optbuf;
352 	(void)&name;
353 #endif
354 
355 	if (realpath(name, mntpath) != NULL && stat(mntpath, &sb) == 0) {
356 		if (!S_ISDIR(sb.st_mode)) {
357 			warnx("%s: not a directory", mntpath);
358 			return (1);
359 		}
360 	} else {
361 		warn("%s", mntpath);
362 		return (1);
363 	}
364 
365 	name = mntpath;
366 
367 	if (mntopts == NULL)
368 		mntopts = "";
369 	if (options == NULL) {
370 		if (*mntopts == '\0') {
371 			options = "rw";
372 		} else {
373 			options = mntopts;
374 			mntopts = "";
375 		}
376 	}
377 	optbuf = catopt(strdup(mntopts), options);
378 
379 	if (strcmp(name, "/") == 0)
380 		flags |= MNT_UPDATE;
381 	if (flags & MNT_FORCE)
382 		optbuf = catopt(optbuf, "force");
383 	if (flags & MNT_RDONLY)
384 		optbuf = catopt(optbuf, "ro");
385 	/*
386 	 * XXX
387 	 * The mount_mfs (newfs) command uses -o to select the
388 	 * optimization mode.  We don't pass the default "-o rw"
389 	 * for that reason.
390 	 */
391 	if (flags & MNT_UPDATE)
392 		optbuf = catopt(optbuf, "update");
393 
394 	argc = 0;
395 	argv[argc++] = vfstype;
396 	mangle(optbuf, &argc, argv);
397 	argv[argc++] = spec;
398 	argv[argc++] = name;
399 	argv[argc] = NULL;
400 
401 	if (debug) {
402 		(void)printf("exec: mount_%s", vfstype);
403 		for (i = 1; i < argc; i++)
404 			(void)printf(" %s", argv[i]);
405 		(void)printf("\n");
406 		return (0);
407 	}
408 
409 	switch (pid = fork()) {
410 	case -1:				/* Error. */
411 		warn("fork");
412 		free(optbuf);
413 		return (1);
414 	case 0:					/* Child. */
415 		if (strcmp(vfstype, "ufs") == 0)
416 			exit(mount_ufs(argc, (char * const *) argv));
417 
418 		/* Go find an executable. */
419 		for (edir = edirs; *edir; edir++) {
420 			(void)snprintf(execname,
421 			    sizeof(execname), "%s/mount_%s", *edir, vfstype);
422 			execv(execname, (char * const *)argv);
423 		}
424 		if (errno == ENOENT) {
425 			int len = 0;
426 			char *cp;
427 			for (edir = edirs; *edir; edir++)
428 				len += strlen(*edir) + 2;	/* ", " */
429 			if ((cp = malloc(len)) == NULL)
430 				errx(1, "malloc failed");
431 			cp[0] = '\0';
432 			for (edir = edirs; *edir; edir++) {
433 				strcat(cp, *edir);
434 				if (edir[1] != NULL)
435 					strcat(cp, ", ");
436 			}
437 			warn("exec mount_%s not found in %s", vfstype, cp);
438 		}
439 		exit(1);
440 		/* NOTREACHED */
441 	default:				/* Parent. */
442 		free(optbuf);
443 
444 		if (waitpid(pid, &status, 0) < 0) {
445 			warn("waitpid");
446 			return (1);
447 		}
448 
449 		if (WIFEXITED(status)) {
450 			if (WEXITSTATUS(status) != 0)
451 				return (WEXITSTATUS(status));
452 		} else if (WIFSIGNALED(status)) {
453 			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
454 			return (1);
455 		}
456 
457 		if (verbose) {
458 			if (statfs(name, &sf) < 0) {
459 				warn("statfs %s", name);
460 				return (1);
461 			}
462 			if (fstab_style)
463 				putfsent(&sf);
464 			else
465 				prmount(&sf);
466 		}
467 		break;
468 	}
469 
470 	return (0);
471 }
472 
473 void
474 prmount(sfp)
475 	struct statfs *sfp;
476 {
477 	int flags;
478 	struct opt *o;
479 	struct passwd *pw;
480 	int f;
481 
482 	(void)printf("%s on %s", sfp->f_mntfromname, sfp->f_mntonname);
483 
484 	flags = sfp->f_flags & MNT_VISFLAGMASK;
485 	for (f = 0, o = optnames; flags && o->o_opt; o++)
486 		if (flags & o->o_opt) {
487 			(void)printf("%s%s", !f++ ? " (" : ", ", o->o_name);
488 			flags &= ~o->o_opt;
489 		}
490 	if (sfp->f_owner) {
491 		(void)printf("%smounted by ", !f++ ? " (" : ", ");
492 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
493 			(void)printf("%s", pw->pw_name);
494 		else
495 			(void)printf("%d", sfp->f_owner);
496 	}
497 	if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
498 		(void)printf("%swrites: sync %ld async %ld",
499 		    !f++ ? " (" : ", ", sfp->f_syncwrites, sfp->f_asyncwrites);
500 	(void)printf("%s\n", f ? ")" : "");
501 }
502 
503 struct statfs *
504 getmntpt(name)
505 	const char *name;
506 {
507 	struct statfs *mntbuf;
508 	int i, mntsize;
509 
510 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
511 	for (i = 0; i < mntsize; i++)
512 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
513 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
514 			return (&mntbuf[i]);
515 	return (NULL);
516 }
517 
518 char *
519 catopt(s0, s1)
520 	char *s0;
521 	const char *s1;
522 {
523 	size_t i;
524 	char *cp;
525 
526 	if (s0 && *s0) {
527 		i = strlen(s0) + strlen(s1) + 1 + 1;
528 		if ((cp = malloc(i)) == NULL)
529 			errx(1, "malloc failed");
530 		(void)snprintf(cp, i, "%s,%s", s0, s1);
531 	} else
532 		cp = strdup(s1);
533 
534 	if (s0)
535 		free(s0);
536 	return (cp);
537 }
538 
539 void
540 mangle(options, argcp, argv)
541 	char *options;
542 	int *argcp;
543 	const char **argv;
544 {
545 	char *p, *s;
546 	int argc;
547 
548 	argc = *argcp;
549 	for (s = options; (p = strsep(&s, ",")) != NULL;)
550 		if (*p != '\0')
551 			if (*p == '-') {
552 				argv[argc++] = p;
553 				p = strchr(p, '=');
554 				if (p) {
555 					*p = '\0';
556 					argv[argc++] = p+1;
557 				}
558 			} else if (strcmp(p, "rw") != 0) {
559 				argv[argc++] = "-o";
560 				argv[argc++] = p;
561 			}
562 
563 	*argcp = argc;
564 }
565 
566 void
567 usage()
568 {
569 
570 	(void)fprintf(stderr, "%s\n%s\n%s\n",
571 "usage: mount [-dfpruvw] [-o options] [-t ufs | external_type] special node",
572 "       mount [-adfpruvw] [-t ufs | external_type]",
573 "       mount [-dfpruvw] special | node");
574 	exit(1);
575 }
576 
577 void
578 putfsent(ent)
579 	const struct statfs *ent;
580 {
581 	struct fstab *fst;
582 
583 	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
584 	    ent->f_fstypename, (ent->f_flags & MNT_RDONLY) ? "ro" : "rw");
585 
586 	/* XXX should use optnames[] - put shorter names in it. */
587 	if (ent->f_flags & MNT_SYNCHRONOUS)
588 		printf(",sync");
589 	if (ent->f_flags & MNT_NOEXEC)
590 		printf(",noexec");
591 	if (ent->f_flags & MNT_NOSUID)
592 		printf(",nosuid");
593 	if (ent->f_flags & MNT_NODEV)
594 		printf(",nodev");
595 	if (ent->f_flags & MNT_UNION)
596 		printf(",union");
597 	if (ent->f_flags & MNT_ASYNC)
598 		printf(",async");
599 	if (ent->f_flags & MNT_NOATIME)
600 		printf(",noatime");
601 	if (ent->f_flags & MNT_NOCLUSTERR)
602 		printf(",noclusterr");
603 	if (ent->f_flags & MNT_NOCLUSTERW)
604 		printf(",noclusterw");
605 	if (ent->f_flags & MNT_NOSYMFOLLOW)
606 		printf (",nosymfollow");
607 	if (ent->f_flags & MNT_SUIDDIR)
608 		printf(",suiddir");
609 
610 	if ((fst = getfsspec(ent->f_mntfromname)))
611 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
612 	else if ((fst = getfsfile(ent->f_mntonname)))
613 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
614 	else if (strcmp(ent->f_fstypename, "ufs") == 0)
615 		printf("\t1 1\n");
616 	else
617 		printf("\t0 0\n");
618 }
619