mount.c revision 52095 
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 52095 1999-10-10 15:52:21Z green $";
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 '@', and the spec is not a file with those
262		 * characters, then assume that an NFS filesystem is being
263		 * specified ala Sun.
264		 */
265		if (vfslist == NULL && strpbrk(argv[0], ":@") != NULL &&
266		    access(argv[0], 0) == -1)
267			vfstype = "nfs";
268		rval = mountfs(vfstype,
269		    argv[0], argv[1], init_flags, options, NULL);
270		break;
271	default:
272		usage();
273		/* NOTREACHED */
274	}
275
276	/*
277	 * If the mount was successfully, and done by root, tell mountd the
278	 * good news.  Pid checks are probably unnecessary, but don't hurt.
279	 */
280	if (rval == 0 && getuid() == 0 &&
281	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
282		if (fscanf(mountdfp, "%d", &pid) == 1 &&
283		     pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
284			err(1, "signal mountd");
285		(void)fclose(mountdfp);
286	}
287
288	exit(rval);
289}
290
291int
292ismounted(fs, mntbuf, mntsize)
293	struct fstab *fs;
294	struct statfs *mntbuf;
295	int mntsize;
296{
297	int i;
298
299	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
300		/* the root file system can always be remounted */
301		return (0);
302
303	for (i = mntsize - 1; i >= 0; --i)
304		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
305		    (!isremountable(fs->fs_vfstype) ||
306		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
307			return (1);
308	return (0);
309}
310
311int
312isremountable(vfsname)
313	const char *vfsname;
314{
315	const char **cp;
316
317	for (cp = remountable_fs_names; *cp; cp++)
318		if (strcmp(*cp, vfsname) == 0)
319			return (1);
320	return (0);
321}
322
323int
324hasopt(mntopts, option)
325	const char *mntopts, *option;
326{
327	int negative, found;
328	char *opt, *optbuf;
329
330	if (option[0] == 'n' && option[1] == 'o') {
331		negative = 1;
332		option += 2;
333	} else
334		negative = 0;
335	optbuf = strdup(mntopts);
336	found = 0;
337	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
338		if (opt[0] == 'n' && opt[1] == 'o') {
339			if (!strcasecmp(opt + 2, option))
340				found = negative;
341		} else if (!strcasecmp(opt, option))
342			found = !negative;
343	}
344	free(optbuf);
345	return (found);
346}
347
348int
349mountfs(vfstype, spec, name, flags, options, mntopts)
350	const char *vfstype, *spec, *name, *options, *mntopts;
351	int flags;
352{
353	/* List of directories containing mount_xxx subcommands. */
354	static const char *edirs[] = {
355		_PATH_SBIN,
356		_PATH_USRSBIN,
357		NULL
358	};
359	const char *argv[100], **edir;
360	struct statfs sf;
361	pid_t pid;
362	int argc, i, status;
363	char *optbuf, execname[MAXPATHLEN + 1], mntpath[MAXPATHLEN];
364
365#if __GNUC__
366	(void)&optbuf;
367	(void)&name;
368#endif
369
370	/* resolve the mountpoint with realpath(3) */
371	(void)checkpath(name, mntpath);
372	name = mntpath;
373
374	if (mntopts == NULL)
375		mntopts = "";
376	if (options == NULL) {
377		if (*mntopts == '\0') {
378			options = "rw";
379		} else {
380			options = mntopts;
381			mntopts = "";
382		}
383	}
384	optbuf = catopt(strdup(mntopts), options);
385
386	if (strcmp(name, "/") == 0)
387		flags |= MNT_UPDATE;
388	if (flags & MNT_FORCE)
389		optbuf = catopt(optbuf, "force");
390	if (flags & MNT_RDONLY)
391		optbuf = catopt(optbuf, "ro");
392	/*
393	 * XXX
394	 * The mount_mfs (newfs) command uses -o to select the
395	 * optimization mode.  We don't pass the default "-o rw"
396	 * for that reason.
397	 */
398	if (flags & MNT_UPDATE)
399		optbuf = catopt(optbuf, "update");
400
401	argc = 0;
402	argv[argc++] = vfstype;
403	mangle(optbuf, &argc, argv);
404	argv[argc++] = spec;
405	argv[argc++] = name;
406	argv[argc] = NULL;
407
408	if (debug) {
409		(void)printf("exec: mount_%s", vfstype);
410		for (i = 1; i < argc; i++)
411			(void)printf(" %s", argv[i]);
412		(void)printf("\n");
413		return (0);
414	}
415
416	switch (pid = fork()) {
417	case -1:				/* Error. */
418		warn("fork");
419		free(optbuf);
420		return (1);
421	case 0:					/* Child. */
422		if (strcmp(vfstype, "ufs") == 0)
423			exit(mount_ufs(argc, (char * const *) argv));
424
425		/* Go find an executable. */
426		for (edir = edirs; *edir; edir++) {
427			(void)snprintf(execname,
428			    sizeof(execname), "%s/mount_%s", *edir, vfstype);
429			execv(execname, (char * const *)argv);
430		}
431		if (errno == ENOENT) {
432			int len = 0;
433			char *cp;
434			for (edir = edirs; *edir; edir++)
435				len += strlen(*edir) + 2;	/* ", " */
436			if ((cp = malloc(len)) == NULL)
437				errx(1, "malloc failed");
438			cp[0] = '\0';
439			for (edir = edirs; *edir; edir++) {
440				strcat(cp, *edir);
441				if (edir[1] != NULL)
442					strcat(cp, ", ");
443			}
444			warn("exec mount_%s not found in %s", vfstype, cp);
445		}
446		exit(1);
447		/* NOTREACHED */
448	default:				/* Parent. */
449		free(optbuf);
450
451		if (waitpid(pid, &status, 0) < 0) {
452			warn("waitpid");
453			return (1);
454		}
455
456		if (WIFEXITED(status)) {
457			if (WEXITSTATUS(status) != 0)
458				return (WEXITSTATUS(status));
459		} else if (WIFSIGNALED(status)) {
460			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
461			return (1);
462		}
463
464		if (verbose) {
465			if (statfs(name, &sf) < 0) {
466				warn("statfs %s", name);
467				return (1);
468			}
469			if (fstab_style)
470				putfsent(&sf);
471			else
472				prmount(&sf);
473		}
474		break;
475	}
476
477	return (0);
478}
479
480void
481prmount(sfp)
482	struct statfs *sfp;
483{
484	int flags;
485	struct opt *o;
486	struct passwd *pw;
487
488	(void)printf("%s on %s (%s", sfp->f_mntfromname, sfp->f_mntonname,
489	    sfp->f_fstypename);
490
491	flags = sfp->f_flags & MNT_VISFLAGMASK;
492	for (o = optnames; flags && o->o_opt; o++)
493		if (flags & o->o_opt) {
494			(void)printf(", %s", o->o_name);
495			flags &= ~o->o_opt;
496		}
497	if (sfp->f_owner) {
498		(void)printf(", mounted by ");
499		if ((pw = getpwuid(sfp->f_owner)) != NULL)
500			(void)printf("%s", pw->pw_name);
501		else
502			(void)printf("%d", sfp->f_owner);
503	}
504	if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
505		(void)printf(", writes: sync %ld async %ld",
506		    sfp->f_syncwrites, sfp->f_asyncwrites);
507	(void)printf(")\n");
508}
509
510struct statfs *
511getmntpt(name)
512	const char *name;
513{
514	struct statfs *mntbuf;
515	int i, mntsize;
516
517	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
518	for (i = 0; i < mntsize; i++)
519		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
520		    strcmp(mntbuf[i].f_mntonname, name) == 0)
521			return (&mntbuf[i]);
522	return (NULL);
523}
524
525char *
526catopt(s0, s1)
527	char *s0;
528	const char *s1;
529{
530	size_t i;
531	char *cp;
532
533	if (s1 == NULL || *s1 == '\0')
534		return s0;
535
536	if (s0 && *s0) {
537		i = strlen(s0) + strlen(s1) + 1 + 1;
538		if ((cp = malloc(i)) == NULL)
539			errx(1, "malloc failed");
540		(void)snprintf(cp, i, "%s,%s", s0, s1);
541	} else
542		cp = strdup(s1);
543
544	if (s0)
545		free(s0);
546	return (cp);
547}
548
549void
550mangle(options, argcp, argv)
551	char *options;
552	int *argcp;
553	const char **argv;
554{
555	char *p, *s;
556	int argc;
557
558	argc = *argcp;
559	for (s = options; (p = strsep(&s, ",")) != NULL;)
560		if (*p != '\0') {
561			if (*p == '-') {
562				argv[argc++] = p;
563				p = strchr(p, '=');
564				if (p) {
565					*p = '\0';
566					argv[argc++] = p+1;
567				}
568			} else if (strcmp(p, "rw") != 0) {
569				argv[argc++] = "-o";
570				argv[argc++] = p;
571			}
572		}
573
574	*argcp = argc;
575}
576
577
578char *
579update_options(opts, fstab, curflags)
580	char *opts;
581	char *fstab;
582	int curflags;
583{
584	char *o, *p;
585	char *cur;
586	char *expopt, *newopt, *tmpopt;
587
588	if (opts == NULL)
589		return strdup("");
590
591	if (fstab == NULL)
592		fstab = strdup("");
593
594	/* remove meta options from list */
595	remopt(fstab, MOUNT_META_OPTION_FSTAB);
596	remopt(fstab, MOUNT_META_OPTION_CURRENT);
597	cur = flags2opts(curflags);
598
599	/*
600	 * Expand all meta-options passed to us first.
601	 */
602	expopt = NULL;
603	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
604		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
605			expopt = catopt(expopt, fstab);
606		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
607			expopt = catopt(expopt, cur);
608		else
609			expopt = catopt(expopt, o);
610	}
611	if (fstab == "")
612		free(fstab);
613	free(cur);
614	free(opts);
615
616	/*
617	 * Remove previous contradictory arguments. Given option "foo" we
618	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
619	 * and "foo" - so we can deal with possible options like "notice".
620	 */
621	newopt = NULL;
622	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
623		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
624			errx(1, "malloc failed");
625
626		strcpy(tmpopt, "no");
627		strcat(tmpopt, o);
628		remopt(newopt, tmpopt);
629		free(tmpopt);
630
631		if (strncmp("no", o, 2) == 0)
632			remopt(newopt, o+2);
633
634		newopt = catopt(newopt, o);
635	}
636	free(expopt);
637
638	return newopt;
639}
640
641void
642remopt(string, opt)
643	char *string;
644 	const char *opt;
645{
646	char *o, *p, *r;
647
648	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
649		return;
650
651	r = string;
652
653	for (p = string; (o = strsep(&p, ",")) != NULL;) {
654		if (strcmp(opt, o) != 0) {
655			if (*r == ',' && *o != '\0')
656				r++;
657			while ((*r++ = *o++) != '\0')
658			    ;
659			*--r = ',';
660		}
661	}
662	*r = '\0';
663}
664
665void
666usage()
667{
668
669	(void)fprintf(stderr, "%s\n%s\n%s\n",
670"usage: mount [-dfpruvw] [-o options] [-t ufs | external_type] special node",
671"       mount [-adfpruvw] [-t ufs | external_type]",
672"       mount [-dfpruvw] special | node");
673	exit(1);
674}
675
676void
677putfsent(ent)
678	const struct statfs *ent;
679{
680	struct fstab *fst;
681	char *opts;
682
683	opts = flags2opts(ent->f_flags);
684	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
685	    ent->f_fstypename, opts);
686	free(opts);
687
688	if ((fst = getfsspec(ent->f_mntfromname)))
689		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
690	else if ((fst = getfsfile(ent->f_mntonname)))
691		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
692	else if (strcmp(ent->f_fstypename, "ufs") == 0)
693		printf("\t1 1\n");
694	else
695		printf("\t0 0\n");
696}
697
698
699char *
700flags2opts(flags)
701	int flags;
702{
703	char *res;
704
705	res = NULL;
706
707	res = catopt(res, (flags & MNT_RDONLY) ? "ro" : "rw");
708
709	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
710	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
711	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
712	if (flags & MNT_NODEV)		res = catopt(res, "nodev");
713	if (flags & MNT_UNION)		res = catopt(res, "union");
714	if (flags & MNT_ASYNC)		res = catopt(res, "async");
715	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
716	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
717	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
718	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
719	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
720
721	return res;
722}
723