xref: /freebsd/sbin/mount/mount.c (revision 0de89efe5c443f213c7ea28773ef2dc6cf3af2ed)
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 #else
44 static const char rcsid[] =
45 	"$Id: mount.c,v 1.19 1997/08/24 21:02:49 steve Exp $";
46 #endif
47 #endif /* not lint */
48 
49 #include <sys/param.h>
50 #include <sys/mount.h>
51 #include <sys/stat.h>
52 #include <sys/wait.h>
53 
54 #include <err.h>
55 #include <errno.h>
56 #include <fstab.h>
57 #include <pwd.h>
58 #include <signal.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <unistd.h>
63 
64 #include "extern.h"
65 #include "pathnames.h"
66 
67 int debug, fstab_style, verbose;
68 
69 char   *catopt __P((char *, const char *));
70 struct statfs
71        *getmntpt __P((const char *));
72 int	hasopt __P((const char *, const char *));
73 int	ismounted __P((struct fstab *, struct statfs *, int));
74 int	isremountable __P((const char *));
75 void	mangle __P((char *, int *, const char **));
76 int	mountfs __P((const char *, const char *, const char *,
77 			int, const char *, const char *));
78 void	prmount __P((struct statfs *));
79 void	putfsent __P((const struct statfs *));
80 void	usage __P((void));
81 
82 /* Map from mount otions to printable formats. */
83 static struct opt {
84 	int o_opt;
85 	const char *o_name;
86 } optnames[] = {
87 	{ MNT_ASYNC,		"asynchronous" },
88 	{ MNT_EXPORTED,		"NFS exported" },
89 	{ MNT_LOCAL,		"local" },
90 	{ MNT_NOATIME,		"noatime" },
91 	{ MNT_NODEV,		"nodev" },
92 	{ MNT_NOEXEC,		"noexec" },
93 	{ MNT_NOSUID,		"nosuid" },
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 	{ NULL }
101 };
102 
103 /*
104  * List of VFS types that can be remounted without becoming mounted on top
105  * of each other.
106  * XXX Is this list correct?
107  */
108 static const char *
109 remountable_fs_names[] = {
110 	"ufs", "ffs", "lfs", "ext2fs",
111 	0
112 };
113 
114 int
115 main(argc, argv)
116 	int argc;
117 	char * const argv[];
118 {
119 	const char *mntfromname, **vfslist, *vfstype;
120 	struct fstab *fs;
121 	struct statfs *mntbuf;
122 	FILE *mountdfp;
123 	pid_t pid;
124 	int all, ch, i, init_flags, mntsize, rval;
125 	char *options;
126 
127 	all = init_flags = 0;
128 	options = NULL;
129 	vfslist = NULL;
130 	vfstype = "ufs";
131 	while ((ch = getopt(argc, argv, "adfo:prwt:uv")) != -1)
132 		switch (ch) {
133 		case 'a':
134 			all = 1;
135 			break;
136 		case 'd':
137 			debug = 1;
138 			break;
139 		case 'f':
140 			init_flags |= MNT_FORCE;
141 			break;
142 		case 'o':
143 			if (*optarg)
144 				options = catopt(options, optarg);
145 			break;
146 		case 'p':
147 			fstab_style = 1;
148 			verbose = 1;
149 			break;
150 		case 'r':
151 			init_flags |= MNT_RDONLY;
152 			break;
153 		case 't':
154 			if (vfslist != NULL)
155 				errx(1, "only one -t option may be specified.");
156 			vfslist = makevfslist(optarg);
157 			vfstype = optarg;
158 			break;
159 		case 'u':
160 			init_flags |= MNT_UPDATE;
161 			break;
162 		case 'v':
163 			verbose = 1;
164 			break;
165 		case 'w':
166 			init_flags &= ~MNT_RDONLY;
167 			break;
168 		case '?':
169 		default:
170 			usage();
171 			/* NOTREACHED */
172 		}
173 	argc -= optind;
174 	argv += optind;
175 
176 #define	BADTYPE(type)							\
177 	(strcmp(type, FSTAB_RO) &&					\
178 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
179 
180 	rval = 0;
181 	switch (argc) {
182 	case 0:
183 		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
184 			err(1, "getmntinfo");
185 		if (all) {
186 			while ((fs = getfsent()) != NULL) {
187 				if (BADTYPE(fs->fs_type))
188 					continue;
189 				if (checkvfsname(fs->fs_vfstype, vfslist))
190 					continue;
191 				if (hasopt(fs->fs_mntops, "noauto"))
192 					continue;
193 				if (ismounted(fs, mntbuf, mntsize))
194 					continue;
195 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
196 				    fs->fs_file, init_flags, options,
197 				    fs->fs_mntops))
198 					rval = 1;
199 			}
200 		} else if (fstab_style) {
201 			for (i = 0; i < mntsize; i++) {
202 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
203 					continue;
204 				putfsent(&mntbuf[i]);
205 			}
206 		} else {
207 			for (i = 0; i < mntsize; i++) {
208 				if (checkvfsname(mntbuf[i].f_fstypename,
209 				    vfslist))
210 					continue;
211 				prmount(&mntbuf[i]);
212 			}
213 		}
214 		exit(rval);
215 	case 1:
216 		if (vfslist != NULL)
217 			usage();
218 
219 		if (init_flags & MNT_UPDATE) {
220 			if ((mntbuf = getmntpt(*argv)) == NULL)
221 				errx(1,
222 				    "unknown special file or file system %s.",
223 				    *argv);
224 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL)
225 				mntfromname = fs->fs_spec;
226 			else
227 				mntfromname = mntbuf->f_mntfromname;
228 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
229 			    mntbuf->f_mntonname, init_flags, options, 0);
230 			break;
231 		}
232 		if ((fs = getfsfile(*argv)) == NULL &&
233 		    (fs = getfsspec(*argv)) == NULL)
234 			errx(1, "%s: unknown special file or file system.",
235 			    *argv);
236 		if (BADTYPE(fs->fs_type))
237 			errx(1, "%s has unknown file system type.",
238 			    *argv);
239 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
240 		    init_flags, options, fs->fs_mntops);
241 		break;
242 	case 2:
243 		/*
244 		 * If -t flag has not been specified, and spec contains either
245 		 * a ':' or a '@' then assume that an NFS filesystem is being
246 		 * specified ala Sun.
247 		 */
248 		if (vfslist == NULL && strpbrk(argv[0], ":@") != NULL)
249 			vfstype = "nfs";
250 		rval = mountfs(vfstype,
251 		    argv[0], argv[1], init_flags, options, NULL);
252 		break;
253 	default:
254 		usage();
255 		/* NOTREACHED */
256 	}
257 
258 	/*
259 	 * If the mount was successfully, and done by root, tell mountd the
260 	 * good news.  Pid checks are probably unnecessary, but don't hurt.
261 	 */
262 	if (rval == 0 && getuid() == 0 &&
263 	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
264 		if (fscanf(mountdfp, "%d", &pid) == 1 &&
265 		     pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
266 			err(1, "signal mountd");
267 		(void)fclose(mountdfp);
268 	}
269 
270 	exit(rval);
271 }
272 
273 int
274 ismounted(fs, mntbuf, mntsize)
275 	struct fstab *fs;
276 	struct statfs *mntbuf;
277 	int mntsize;
278 {
279 	int i;
280 
281 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
282 		/* the root file system can always be remounted */
283 		return (0);
284 
285 	for (i = mntsize - 1; i >= 0; --i)
286 		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
287 		    (!isremountable(fs->fs_vfstype) ||
288 		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
289 			return (1);
290 	return (0);
291 }
292 
293 int
294 isremountable(vfsname)
295 	const char *vfsname;
296 {
297 	const char **cp;
298 
299 	for (cp = remountable_fs_names; *cp; cp++)
300 		if (strcmp(*cp, vfsname) == 0)
301 			return (1);
302 	return (0);
303 }
304 
305 int
306 hasopt(mntopts, option)
307 	const char *mntopts, *option;
308 {
309 	int negative, found;
310 	char *opt, *optbuf;
311 
312 	if (option[0] == 'n' && option[1] == 'o') {
313 		negative = 1;
314 		option += 2;
315 	} else
316 		negative = 0;
317 	optbuf = strdup(mntopts);
318 	found = 0;
319 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
320 		if (opt[0] == 'n' && opt[1] == 'o') {
321 			if (!strcasecmp(opt + 2, option))
322 				found = negative;
323 		} else if (!strcasecmp(opt, option))
324 			found = !negative;
325 	}
326 	free(optbuf);
327 	return (found);
328 }
329 
330 int
331 mountfs(vfstype, spec, name, flags, options, mntopts)
332 	const char *vfstype, *spec, *name, *options, *mntopts;
333 	int flags;
334 {
335 	/* List of directories containing mount_xxx subcommands. */
336 	static const char *edirs[] = {
337 		_PATH_SBIN,
338 		_PATH_USRSBIN,
339 		NULL
340 	};
341 	const char *argv[100], **edir;
342 	struct stat sb;
343 	struct statfs sf;
344 	pid_t pid;
345 	int argc, i, status;
346 	char *optbuf, execname[MAXPATHLEN + 1], mntpath[MAXPATHLEN];
347 
348 #if __GNUC__
349 	(void)&optbuf;
350 	(void)&name;
351 #endif
352 
353 	if (realpath(name, mntpath) != NULL && stat(mntpath, &sb) == 0) {
354 		if (!S_ISDIR(sb.st_mode)) {
355 			warnx("%s: Not a directory", mntpath);
356 			return (1);
357 		}
358 	} else {
359 		warn("%s", mntpath);
360 		return (1);
361 	}
362 
363 	name = mntpath;
364 
365 	if (mntopts == NULL)
366 		mntopts = "";
367 	if (options == NULL) {
368 		if (*mntopts == '\0') {
369 			options = "rw";
370 		} else {
371 			options = mntopts;
372 			mntopts = "";
373 		}
374 	}
375 	optbuf = catopt(strdup(mntopts), options);
376 
377 	if (strcmp(name, "/") == 0)
378 		flags |= MNT_UPDATE;
379 	if (flags & MNT_FORCE)
380 		optbuf = catopt(optbuf, "force");
381 	if (flags & MNT_RDONLY)
382 		optbuf = catopt(optbuf, "ro");
383 	/*
384 	 * XXX
385 	 * The mount_mfs (newfs) command uses -o to select the
386 	 * optimisation mode.  We don't pass the default "-o rw"
387 	 * for that reason.
388 	 */
389 	if (flags & MNT_UPDATE)
390 		optbuf = catopt(optbuf, "update");
391 
392 	argc = 0;
393 	argv[argc++] = vfstype;
394 	mangle(optbuf, &argc, argv);
395 	argv[argc++] = spec;
396 	argv[argc++] = name;
397 	argv[argc] = NULL;
398 
399 	if (debug) {
400 		(void)printf("exec: mount_%s", vfstype);
401 		for (i = 1; i < argc; i++)
402 			(void)printf(" %s", argv[i]);
403 		(void)printf("\n");
404 		return (0);
405 	}
406 
407 	switch (pid = fork()) {
408 	case -1:				/* Error. */
409 		warn("fork");
410 		free(optbuf);
411 		return (1);
412 	case 0:					/* Child. */
413 		if (strcmp(vfstype, "ufs") == 0)
414 			exit(mount_ufs(argc, (char * const *) argv));
415 
416 		/* Go find an executable. */
417 		for (edir = edirs; *edir; edir++) {
418 			(void)snprintf(execname,
419 			    sizeof(execname), "%s/mount_%s", *edir, vfstype);
420 			execv(execname, (char * const *)argv);
421 		}
422 		if (errno == ENOENT) {
423 			int len = 0;
424 			char *cp;
425 			for (edir = edirs; *edir; edir++)
426 				len += strlen(*edir) + 2;	/* ", " */
427 			if ((cp = malloc(len)) == NULL) {
428 				warn(NULL);
429 				exit(1);
430 			}
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 	(void)printf(f ? ")\n" : "\n");
498 }
499 
500 struct statfs *
501 getmntpt(name)
502 	const char *name;
503 {
504 	struct statfs *mntbuf;
505 	int i, mntsize;
506 
507 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
508 	for (i = 0; i < mntsize; i++)
509 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
510 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
511 			return (&mntbuf[i]);
512 	return (NULL);
513 }
514 
515 char *
516 catopt(s0, s1)
517 	char *s0;
518 	const char *s1;
519 {
520 	size_t i;
521 	char *cp;
522 
523 	if (s0 && *s0) {
524 		i = strlen(s0) + strlen(s1) + 1 + 1;
525 		if ((cp = malloc(i)) == NULL)
526 			err(1, NULL);
527 		(void)snprintf(cp, i, "%s,%s", s0, s1);
528 	} else
529 		cp = strdup(s1);
530 
531 	if (s0)
532 		free(s0);
533 	return (cp);
534 }
535 
536 void
537 mangle(options, argcp, argv)
538 	char *options;
539 	int *argcp;
540 	const char **argv;
541 {
542 	char *p, *s;
543 	int argc;
544 
545 	argc = *argcp;
546 	for (s = options; (p = strsep(&s, ",")) != NULL;)
547 		if (*p != '\0')
548 			if (*p == '-') {
549 				argv[argc++] = p;
550 				p = strchr(p, '=');
551 				if (p) {
552 					*p = '\0';
553 					argv[argc++] = p+1;
554 				}
555 			} else if (strcmp(p, "rw") != 0) {
556 				argv[argc++] = "-o";
557 				argv[argc++] = p;
558 			}
559 
560 	*argcp = argc;
561 }
562 
563 void
564 usage()
565 {
566 
567 	(void)fprintf(stderr,
568 		"usage: mount %s %s\n       mount %s\n       mount %s\n",
569 		"[-dfpruvw] [-o options] [-t ufs | external_type]",
570 			"special node",
571 		"[-adfpruvw] [-t ufs | external_type]",
572 		"[-dfpruvw] special | node");
573 	exit(1);
574 }
575 
576 void
577 putfsent(ent)
578 	const struct statfs *ent;
579 {
580 	struct fstab *fst;
581 
582 	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
583 	    ent->f_fstypename, (ent->f_flags & MNT_RDONLY) ? "ro" : "rw");
584 
585 	/* XXX should use optnames[] - put shorter names in it. */
586 	if (ent->f_flags & MNT_SYNCHRONOUS)
587 		printf(",sync");
588 	if (ent->f_flags & MNT_NOEXEC)
589 		printf(",noexec");
590 	if (ent->f_flags & MNT_NOSUID)
591 		printf(",nosuid");
592 	if (ent->f_flags & MNT_NODEV)
593 		printf(",nodev");
594 	if (ent->f_flags & MNT_UNION)
595 		printf(",union");
596 	if (ent->f_flags & MNT_ASYNC)
597 		printf(",async");
598 	if (ent->f_flags & MNT_NOATIME)
599 		printf(",noatime");
600 	if (ent->f_flags & MNT_NOCLUSTERR)
601 		printf(",noclusterr");
602 	if (ent->f_flags & MNT_NOCLUSTERW)
603 		printf(",noclusterw");
604 
605 	if ((fst = getfsspec(ent->f_mntfromname)))
606 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
607 	else if ((fst = getfsfile(ent->f_mntonname)))
608 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
609 	else if (ent->f_type == MOUNT_UFS)
610 		printf("\t1 1\n");
611 	else
612 		printf("\t0 0\n");
613 }
614