mount.c revision 52055 
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
35static 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
42static char sccsid[] = "@(#)mount.c	8.25 (Berkeley) 5/8/95";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/sbin/mount/mount.c 52055 1999-10-09 11:54:14Z phk $";
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 "mntopts.h"
65#include "pathnames.h"
66
67/* `meta' options */
68#define MOUNT_META_OPTION_FSTAB		"fstab"
69#define MOUNT_META_OPTION_CURRENT	"current"
70
71int debug, fstab_style, verbose;
72
73char   *catopt __P((char *, const char *));
74struct statfs
75       *getmntpt __P((const char *));
76int	hasopt __P((const char *, const char *));
77int	ismounted __P((struct fstab *, struct statfs *, int));
78int	isremountable __P((const char *));
79void	mangle __P((char *, int *, const char **));
80char   *update_options __P((char *, char *, int));
81int	mountfs __P((const char *, const char *, const char *,
82			int, const char *, const char *));
83void	remopt __P((char *, const char *));
84void	prmount __P((struct statfs *));
85void	putfsent __P((const struct statfs *));
86void	usage __P((void));
87char   *flags2opts __P((int));
88
89/* Map from mount options to printable formats. */
90static struct opt {
91	int o_opt;
92	const char *o_name;
93} optnames[] = {
94	{ MNT_ASYNC,		"asynchronous" },
95	{ MNT_EXPORTED,		"NFS exported" },
96	{ MNT_LOCAL,		"local" },
97	{ MNT_NOATIME,		"noatime" },
98	{ MNT_NODEV,		"nodev" },
99	{ MNT_NOEXEC,		"noexec" },
100	{ MNT_NOSUID,		"nosuid" },
101	{ MNT_NOSYMFOLLOW,	"nosymfollow" },
102	{ MNT_QUOTA,		"with quotas" },
103	{ MNT_RDONLY,		"read-only" },
104	{ MNT_SYNCHRONOUS,	"synchronous" },
105	{ MNT_UNION,		"union" },
106	{ MNT_NOCLUSTERR,	"noclusterr" },
107	{ MNT_NOCLUSTERW,	"noclusterw" },
108	{ MNT_SUIDDIR,		"suiddir" },
109	{ MNT_SOFTDEP,		"soft-updates" },
110	{ 0, NULL }
111};
112
113/*
114 * List of VFS types that can be remounted without becoming mounted on top
115 * of each other.
116 * XXX Is this list correct?
117 */
118static const char *
119remountable_fs_names[] = {
120	"ufs", "ffs", "lfs", "ext2fs",
121	0
122};
123
124int
125main(argc, argv)
126	int argc;
127	char * const argv[];
128{
129	const char *mntfromname, **vfslist, *vfstype;
130	struct fstab *fs;
131	struct statfs *mntbuf;
132	FILE *mountdfp;
133	pid_t pid;
134	int all, ch, i, init_flags, mntsize, rval;
135	char *options;
136
137	all = init_flags = 0;
138	options = NULL;
139	vfslist = NULL;
140	vfstype = "ufs";
141	while ((ch = getopt(argc, argv, "adfo:prwt:uv")) != -1)
142		switch (ch) {
143		case 'a':
144			all = 1;
145			break;
146		case 'd':
147			debug = 1;
148			break;
149		case 'f':
150			init_flags |= MNT_FORCE;
151			break;
152		case 'o':
153			if (*optarg)
154				options = catopt(options, optarg);
155			break;
156		case 'p':
157			fstab_style = 1;
158			verbose = 1;
159			break;
160		case 'r':
161			init_flags |= MNT_RDONLY;
162			break;
163		case 't':
164			if (vfslist != NULL)
165				errx(1, "only one -t option may be specified");
166			vfslist = makevfslist(optarg);
167			vfstype = optarg;
168			break;
169		case 'u':
170			init_flags |= MNT_UPDATE;
171			break;
172		case 'v':
173			verbose = 1;
174			break;
175		case 'w':
176			init_flags &= ~MNT_RDONLY;
177			break;
178		case '?':
179		default:
180			usage();
181			/* NOTREACHED */
182		}
183	argc -= optind;
184	argv += optind;
185
186#define	BADTYPE(type)							\
187	(strcmp(type, FSTAB_RO) &&					\
188	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
189
190	rval = 0;
191	switch (argc) {
192	case 0:
193		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
194			err(1, "getmntinfo");
195		if (all) {
196			while ((fs = getfsent()) != NULL) {
197				if (BADTYPE(fs->fs_type))
198					continue;
199				if (checkvfsname(fs->fs_vfstype, vfslist))
200					continue;
201				if (hasopt(fs->fs_mntops, "noauto"))
202					continue;
203				if (!(init_flags & MNT_UPDATE) &&
204				    ismounted(fs, mntbuf, mntsize))
205					continue;
206				if (mountfs(fs->fs_vfstype, fs->fs_spec,
207				    fs->fs_file, init_flags, options,
208				    fs->fs_mntops))
209					rval = 1;
210			}
211		} else if (fstab_style) {
212			for (i = 0; i < mntsize; i++) {
213				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
214					continue;
215				putfsent(&mntbuf[i]);
216			}
217		} else {
218			for (i = 0; i < mntsize; i++) {
219				if (checkvfsname(mntbuf[i].f_fstypename,
220				    vfslist))
221					continue;
222				prmount(&mntbuf[i]);
223			}
224		}
225		exit(rval);
226	case 1:
227		if (vfslist != NULL)
228			usage();
229
230		if (init_flags & MNT_UPDATE) {
231			if ((mntbuf = getmntpt(*argv)) == NULL)
232				errx(1,
233				    "unknown special file or file system %s",
234				    *argv);
235			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
236				mntfromname = fs->fs_spec;
237				options = update_options(options, fs->fs_mntops,
238				    mntbuf->f_flags);
239			} else {
240				mntfromname = mntbuf->f_mntfromname;
241				options = update_options(options, NULL,
242				    mntbuf->f_flags);
243			}
244			rval = mountfs(mntbuf->f_fstypename, mntfromname,
245			    mntbuf->f_mntonname, init_flags, options, 0);
246			break;
247		}
248		if ((fs = getfsfile(*argv)) == NULL &&
249		    (fs = getfsspec(*argv)) == NULL)
250			errx(1, "%s: unknown special file or file system",
251			    *argv);
252		if (BADTYPE(fs->fs_type))
253			errx(1, "%s has unknown file system type",
254			    *argv);
255		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
256		    init_flags, options, fs->fs_mntops);
257		break;
258	case 2:
259		/*
260		 * If -t flag has not been specified, and spec contains either
261		 * a ':' or a '@' then assume that an NFS filesystem is being
262		 * specified ala Sun.
263		 */
264		if (vfslist == NULL && strpbrk(argv[0], ":@") != NULL)
265			vfstype = "nfs";
266		rval = mountfs(vfstype,
267		    argv[0], argv[1], init_flags, options, NULL);
268		break;
269	default:
270		usage();
271		/* NOTREACHED */
272	}
273
274	/*
275	 * If the mount was successfully, and done by root, tell mountd the
276	 * good news.  Pid checks are probably unnecessary, but don't hurt.
277	 */
278	if (rval == 0 && getuid() == 0 &&
279	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
280		if (fscanf(mountdfp, "%d", &pid) == 1 &&
281		     pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
282			err(1, "signal mountd");
283		(void)fclose(mountdfp);
284	}
285
286	exit(rval);
287}
288
289int
290ismounted(fs, mntbuf, mntsize)
291	struct fstab *fs;
292	struct statfs *mntbuf;
293	int mntsize;
294{
295	int i;
296
297	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
298		/* the root file system can always be remounted */
299		return (0);
300
301	for (i = mntsize - 1; i >= 0; --i)
302		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
303		    (!isremountable(fs->fs_vfstype) ||
304		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
305			return (1);
306	return (0);
307}
308
309int
310isremountable(vfsname)
311	const char *vfsname;
312{
313	const char **cp;
314
315	for (cp = remountable_fs_names; *cp; cp++)
316		if (strcmp(*cp, vfsname) == 0)
317			return (1);
318	return (0);
319}
320
321int
322hasopt(mntopts, option)
323	const char *mntopts, *option;
324{
325	int negative, found;
326	char *opt, *optbuf;
327
328	if (option[0] == 'n' && option[1] == 'o') {
329		negative = 1;
330		option += 2;
331	} else
332		negative = 0;
333	optbuf = strdup(mntopts);
334	found = 0;
335	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
336		if (opt[0] == 'n' && opt[1] == 'o') {
337			if (!strcasecmp(opt + 2, option))
338				found = negative;
339		} else if (!strcasecmp(opt, option))
340			found = !negative;
341	}
342	free(optbuf);
343	return (found);
344}
345
346int
347mountfs(vfstype, spec, name, flags, options, mntopts)
348	const char *vfstype, *spec, *name, *options, *mntopts;
349	int flags;
350{
351	/* List of directories containing mount_xxx subcommands. */
352	static const char *edirs[] = {
353		_PATH_SBIN,
354		_PATH_USRSBIN,
355		NULL
356	};
357	const char *argv[100], **edir;
358	struct statfs sf;
359	pid_t pid;
360	int argc, i, status;
361	char *optbuf, execname[MAXPATHLEN + 1], mntpath[MAXPATHLEN];
362
363#if __GNUC__
364	(void)&optbuf;
365	(void)&name;
366#endif
367
368	/* resolve the mountpoint with realpath(3) */
369	(void)checkpath(name, mntpath);
370	name = mntpath;
371
372	if (mntopts == NULL)
373		mntopts = "";
374	if (options == NULL) {
375		if (*mntopts == '\0') {
376			options = "rw";
377		} else {
378			options = mntopts;
379			mntopts = "";
380		}
381	}
382	optbuf = catopt(strdup(mntopts), options);
383
384	if (strcmp(name, "/") == 0)
385		flags |= MNT_UPDATE;
386	if (flags & MNT_FORCE)
387		optbuf = catopt(optbuf, "force");
388	if (flags & MNT_RDONLY)
389		optbuf = catopt(optbuf, "ro");
390	/*
391	 * XXX
392	 * The mount_mfs (newfs) command uses -o to select the
393	 * optimization mode.  We don't pass the default "-o rw"
394	 * for that reason.
395	 */
396	if (flags & MNT_UPDATE)
397		optbuf = catopt(optbuf, "update");
398
399	argc = 0;
400	argv[argc++] = vfstype;
401	mangle(optbuf, &argc, argv);
402	argv[argc++] = spec;
403	argv[argc++] = name;
404	argv[argc] = NULL;
405
406	if (debug) {
407		(void)printf("exec: mount_%s", vfstype);
408		for (i = 1; i < argc; i++)
409			(void)printf(" %s", argv[i]);
410		(void)printf("\n");
411		return (0);
412	}
413
414	switch (pid = fork()) {
415	case -1:				/* Error. */
416		warn("fork");
417		free(optbuf);
418		return (1);
419	case 0:					/* Child. */
420		if (strcmp(vfstype, "ufs") == 0)
421			exit(mount_ufs(argc, (char * const *) argv));
422
423		/* Go find an executable. */
424		for (edir = edirs; *edir; edir++) {
425			(void)snprintf(execname,
426			    sizeof(execname), "%s/mount_%s", *edir, vfstype);
427			execv(execname, (char * const *)argv);
428		}
429		if (errno == ENOENT) {
430			int len = 0;
431			char *cp;
432			for (edir = edirs; *edir; edir++)
433				len += strlen(*edir) + 2;	/* ", " */
434			if ((cp = malloc(len)) == NULL)
435				errx(1, "malloc failed");
436			cp[0] = '\0';
437			for (edir = edirs; *edir; edir++) {
438				strcat(cp, *edir);
439				if (edir[1] != NULL)
440					strcat(cp, ", ");
441			}
442			warn("exec mount_%s not found in %s", vfstype, cp);
443		}
444		exit(1);
445		/* NOTREACHED */
446	default:				/* Parent. */
447		free(optbuf);
448
449		if (waitpid(pid, &status, 0) < 0) {
450			warn("waitpid");
451			return (1);
452		}
453
454		if (WIFEXITED(status)) {
455			if (WEXITSTATUS(status) != 0)
456				return (WEXITSTATUS(status));
457		} else if (WIFSIGNALED(status)) {
458			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
459			return (1);
460		}
461
462		if (verbose) {
463			if (statfs(name, &sf) < 0) {
464				warn("statfs %s", name);
465				return (1);
466			}
467			if (fstab_style)
468				putfsent(&sf);
469			else
470				prmount(&sf);
471		}
472		break;
473	}
474
475	return (0);
476}
477
478void
479prmount(sfp)
480	struct statfs *sfp;
481{
482	int flags;
483	struct opt *o;
484	struct passwd *pw;
485
486	(void)printf("%s on %s (%s", sfp->f_mntfromname, sfp->f_mntonname,
487	    sfp->f_fstypename);
488
489	flags = sfp->f_flags & MNT_VISFLAGMASK;
490	for (o = optnames; flags && o->o_opt; o++)
491		if (flags & o->o_opt) {
492			(void)printf(", %s", o->o_name);
493			flags &= ~o->o_opt;
494		}
495	if (sfp->f_owner) {
496		(void)printf(", mounted by ");
497		if ((pw = getpwuid(sfp->f_owner)) != NULL)
498			(void)printf("%s", pw->pw_name);
499		else
500			(void)printf("%d", sfp->f_owner);
501	}
502	if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
503		(void)printf(", writes: sync %ld async %ld",
504		    sfp->f_syncwrites, sfp->f_asyncwrites);
505	(void)printf(")\n");
506}
507
508struct statfs *
509getmntpt(name)
510	const char *name;
511{
512	struct statfs *mntbuf;
513	int i, mntsize;
514
515	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
516	for (i = 0; i < mntsize; i++)
517		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
518		    strcmp(mntbuf[i].f_mntonname, name) == 0)
519			return (&mntbuf[i]);
520	return (NULL);
521}
522
523char *
524catopt(s0, s1)
525	char *s0;
526	const char *s1;
527{
528	size_t i;
529	char *cp;
530
531	if (s1 == NULL || *s1 == '\0')
532		return s0;
533
534	if (s0 && *s0) {
535		i = strlen(s0) + strlen(s1) + 1 + 1;
536		if ((cp = malloc(i)) == NULL)
537			errx(1, "malloc failed");
538		(void)snprintf(cp, i, "%s,%s", s0, s1);
539	} else
540		cp = strdup(s1);
541
542	if (s0)
543		free(s0);
544	return (cp);
545}
546
547void
548mangle(options, argcp, argv)
549	char *options;
550	int *argcp;
551	const char **argv;
552{
553	char *p, *s;
554	int argc;
555
556	argc = *argcp;
557	for (s = options; (p = strsep(&s, ",")) != NULL;)
558		if (*p != '\0') {
559			if (*p == '-') {
560				argv[argc++] = p;
561				p = strchr(p, '=');
562				if (p) {
563					*p = '\0';
564					argv[argc++] = p+1;
565				}
566			} else if (strcmp(p, "rw") != 0) {
567				argv[argc++] = "-o";
568				argv[argc++] = p;
569			}
570		}
571
572	*argcp = argc;
573}
574
575
576char *
577update_options(opts, fstab, curflags)
578	char *opts;
579	char *fstab;
580	int curflags;
581{
582	char *o, *p;
583	char *cur;
584	char *expopt, *newopt, *tmpopt;
585
586	if (opts == NULL)
587		return strdup("");
588
589	if (fstab == NULL)
590		fstab = strdup("");
591
592	/* remove meta options from list */
593	remopt(fstab, MOUNT_META_OPTION_FSTAB);
594	remopt(fstab, MOUNT_META_OPTION_CURRENT);
595	cur = flags2opts(curflags);
596
597	/*
598	 * Expand all meta-options passed to us first.
599	 */
600	expopt = NULL;
601	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
602		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
603			expopt = catopt(expopt, fstab);
604		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
605			expopt = catopt(expopt, cur);
606		else
607			expopt = catopt(expopt, o);
608	}
609	if (fstab == "")
610		free(fstab);
611	free(cur);
612	free(opts);
613
614	/*
615	 * Remove previous contradictory arguments. Given option "foo" we
616	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
617	 * and "foo" - so we can deal with possible options like "notice".
618	 */
619	newopt = NULL;
620	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
621		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
622			errx(1, "malloc failed");
623
624		strcpy(tmpopt, "no");
625		strcat(tmpopt, o);
626		remopt(newopt, tmpopt);
627		free(tmpopt);
628
629		if (strncmp("no", o, 2) == 0)
630			remopt(newopt, o+2);
631
632		newopt = catopt(newopt, o);
633	}
634	free(expopt);
635
636	return newopt;
637}
638
639void
640remopt(string, opt)
641	char *string;
642 	const char *opt;
643{
644	char *o, *p, *r;
645
646	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
647		return;
648
649	r = string;
650
651	for (p = string; (o = strsep(&p, ",")) != NULL;) {
652		if (strcmp(opt, o) != 0) {
653			if (*r == ',' && *o != '\0')
654				r++;
655			while ((*r++ = *o++) != '\0')
656			    ;
657			*--r = ',';
658		}
659	}
660	*r = '\0';
661}
662
663void
664usage()
665{
666
667	(void)fprintf(stderr, "%s\n%s\n%s\n",
668"usage: mount [-dfpruvw] [-o options] [-t ufs | external_type] special node",
669"       mount [-adfpruvw] [-t ufs | external_type]",
670"       mount [-dfpruvw] special | node");
671	exit(1);
672}
673
674void
675putfsent(ent)
676	const struct statfs *ent;
677{
678	struct fstab *fst;
679	char *opts;
680
681	opts = flags2opts(ent->f_flags);
682	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
683	    ent->f_fstypename, opts);
684	free(opts);
685
686	if ((fst = getfsspec(ent->f_mntfromname)))
687		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
688	else if ((fst = getfsfile(ent->f_mntonname)))
689		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
690	else if (strcmp(ent->f_fstypename, "ufs") == 0)
691		printf("\t1 1\n");
692	else
693		printf("\t0 0\n");
694}
695
696
697char *
698flags2opts(flags)
699	int flags;
700{
701	char *res;
702
703	res = NULL;
704
705	res = catopt(res, (flags & MNT_RDONLY) ? "ro" : "rw");
706
707	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
708	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
709	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
710	if (flags & MNT_NODEV)		res = catopt(res, "nodev");
711	if (flags & MNT_UNION)		res = catopt(res, "union");
712	if (flags & MNT_ASYNC)		res = catopt(res, "async");
713	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
714	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
715	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
716	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
717	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
718
719	return res;
720}
721