mount.c revision 28671 
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#else
44static const char rcsid[] =
45	"$Id$";
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
67int debug, fstab_style, verbose;
68
69char   *catopt __P((char *, const char *));
70struct statfs
71       *getmntpt __P((const char *));
72int	hasopt __P((const char *, const char *));
73int	ismounted __P((struct fstab *, struct statfs *, int));
74int	isremountable __P((const char *));
75void	mangle __P((char *, int *, const char **));
76int	mountfs __P((const char *, const char *, const char *,
77			int, const char *, const char *));
78void	prmount __P((struct statfs *));
79void	putfsent __P((const struct statfs *));
80void	usage __P((void));
81
82/* Map from mount otions to printable formats. */
83static 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	{ NULL }
99};
100
101/*
102 * List of VFS types that can be remounted without becoming mounted on top
103 * of each other.
104 * XXX Is this list correct?
105 */
106static const char *
107remountable_fs_names[] = {
108	"ufs", "ffs", "lfs", "ext2fs",
109	0
110};
111
112int
113main(argc, argv)
114	int argc;
115	char * const argv[];
116{
117	const char *mntfromname, **vfslist, *vfstype;
118	struct fstab *fs;
119	struct statfs *mntbuf;
120	FILE *mountdfp;
121	pid_t pid;
122	int all, ch, i, init_flags, mntsize, rval;
123	char *options;
124
125	all = init_flags = 0;
126	options = NULL;
127	vfslist = NULL;
128	vfstype = "ufs";
129	while ((ch = getopt(argc, argv, "adfo:prwt:uv")) != -1)
130		switch (ch) {
131		case 'a':
132			all = 1;
133			break;
134		case 'd':
135			debug = 1;
136			break;
137		case 'f':
138			init_flags |= MNT_FORCE;
139			break;
140		case 'o':
141			if (*optarg)
142				options = catopt(options, optarg);
143			break;
144		case 'p':
145			fstab_style = 1;
146			verbose = 1;
147			break;
148		case 'r':
149			init_flags |= MNT_RDONLY;
150			break;
151		case 't':
152			if (vfslist != NULL)
153				errx(1, "only one -t option may be specified.");
154			vfslist = makevfslist(optarg);
155			vfstype = optarg;
156			break;
157		case 'u':
158			init_flags |= MNT_UPDATE;
159			break;
160		case 'v':
161			verbose = 1;
162			break;
163		case 'w':
164			init_flags &= ~MNT_RDONLY;
165			break;
166		case '?':
167		default:
168			usage();
169			/* NOTREACHED */
170		}
171	argc -= optind;
172	argv += optind;
173
174#define	BADTYPE(type)							\
175	(strcmp(type, FSTAB_RO) &&					\
176	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
177
178	rval = 0;
179	switch (argc) {
180	case 0:
181		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
182			err(1, "getmntinfo");
183		if (all) {
184			while ((fs = getfsent()) != NULL) {
185				if (BADTYPE(fs->fs_type))
186					continue;
187				if (checkvfsname(fs->fs_vfstype, vfslist))
188					continue;
189				if (hasopt(fs->fs_mntops, "noauto"))
190					continue;
191				if (ismounted(fs, mntbuf, mntsize))
192					continue;
193				if (mountfs(fs->fs_vfstype, fs->fs_spec,
194				    fs->fs_file, init_flags, options,
195				    fs->fs_mntops))
196					rval = 1;
197			}
198		} else if (fstab_style) {
199			for (i = 0; i < mntsize; i++) {
200				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
201					continue;
202				putfsent(&mntbuf[i]);
203			}
204		} else {
205			for (i = 0; i < mntsize; i++) {
206				if (checkvfsname(mntbuf[i].f_fstypename,
207				    vfslist))
208					continue;
209				prmount(&mntbuf[i]);
210			}
211		}
212		exit(rval);
213	case 1:
214		if (vfslist != NULL)
215			usage();
216
217		if (init_flags & MNT_UPDATE) {
218			if ((mntbuf = getmntpt(*argv)) == NULL)
219				errx(1,
220				    "unknown special file or file system %s.",
221				    *argv);
222			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL)
223				mntfromname = fs->fs_spec;
224			else
225				mntfromname = mntbuf->f_mntfromname;
226			rval = mountfs(mntbuf->f_fstypename, mntfromname,
227			    mntbuf->f_mntonname, init_flags, options, 0);
228			break;
229		}
230		if ((fs = getfsfile(*argv)) == NULL &&
231		    (fs = getfsspec(*argv)) == NULL)
232			errx(1, "%s: unknown special file or file system.",
233			    *argv);
234		if (BADTYPE(fs->fs_type))
235			errx(1, "%s has unknown file system type.",
236			    *argv);
237		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
238		    init_flags, options, fs->fs_mntops);
239		break;
240	case 2:
241		/*
242		 * If -t flag has not been specified, and spec contains either
243		 * a ':' or a '@' then assume that an NFS filesystem is being
244		 * specified ala Sun.
245		 */
246		if (vfslist == NULL && strpbrk(argv[0], ":@") != NULL)
247			vfstype = "nfs";
248		rval = mountfs(vfstype,
249		    argv[0], argv[1], init_flags, options, NULL);
250		break;
251	default:
252		usage();
253		/* NOTREACHED */
254	}
255
256	/*
257	 * If the mount was successfully, and done by root, tell mountd the
258	 * good news.  Pid checks are probably unnecessary, but don't hurt.
259	 */
260	if (rval == 0 && getuid() == 0 &&
261	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
262		if (fscanf(mountdfp, "%d", &pid) == 1 &&
263		     pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
264			err(1, "signal mountd");
265		(void)fclose(mountdfp);
266	}
267
268	exit(rval);
269}
270
271int
272ismounted(fs, mntbuf, mntsize)
273	struct fstab *fs;
274	struct statfs *mntbuf;
275	int mntsize;
276{
277	int i;
278
279	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
280		/* the root file system can always be remounted */
281		return (0);
282
283	for (i = mntsize - 1; i >= 0; --i)
284		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
285		    (!isremountable(fs->fs_vfstype) ||
286		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
287			return (1);
288	return (0);
289}
290
291int
292isremountable(vfsname)
293	const char *vfsname;
294{
295	const char **cp;
296
297	for (cp = remountable_fs_names; *cp; cp++)
298		if (strcmp(*cp, vfsname) == 0)
299			return (1);
300	return (0);
301}
302
303int
304hasopt(mntopts, option)
305	const char *mntopts, *option;
306{
307	int negative, found;
308	char *opt, *optbuf;
309
310	if (option[0] == 'n' && option[1] == 'o') {
311		negative = 1;
312		option += 2;
313	} else
314		negative = 0;
315	optbuf = strdup(mntopts);
316	found = 0;
317	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
318		if (opt[0] == 'n' && opt[1] == 'o') {
319			if (!strcasecmp(opt + 2, option))
320				found = negative;
321		} else if (!strcasecmp(opt, option))
322			found = !negative;
323	}
324	free(optbuf);
325	return (found);
326}
327
328int
329mountfs(vfstype, spec, name, flags, options, mntopts)
330	const char *vfstype, *spec, *name, *options, *mntopts;
331	int flags;
332{
333	/* List of directories containing mount_xxx subcommands. */
334	static const char *edirs[] = {
335		_PATH_SBIN,
336		_PATH_USRSBIN,
337		NULL
338	};
339	const char *argv[100], **edir;
340	struct stat sb;
341	struct statfs sf;
342	pid_t pid;
343	int argc, i, status;
344	char *optbuf, execname[MAXPATHLEN + 1], mntpath[MAXPATHLEN];
345
346#if __GNUC__
347	(void)&optbuf;
348	(void)&name;
349#endif
350
351	if (realpath(name, mntpath) != NULL && stat(mntpath, &sb) == 0) {
352		if (!S_ISDIR(sb.st_mode)) {
353			warnx("%s: Not a directory", mntpath);
354			return (1);
355		}
356	} else {
357		warn("%s", mntpath);
358		return (1);
359	}
360
361	name = mntpath;
362
363	if (mntopts == NULL)
364		mntopts = "";
365	if (options == NULL) {
366		if (*mntopts == '\0') {
367			options = "rw";
368		} else {
369			options = mntopts;
370			mntopts = "";
371		}
372	}
373	optbuf = catopt(strdup(mntopts), options);
374
375	if (strcmp(name, "/") == 0)
376		flags |= MNT_UPDATE;
377	if (flags & MNT_FORCE)
378		optbuf = catopt(optbuf, "force");
379	if (flags & MNT_RDONLY)
380		optbuf = catopt(optbuf, "ro");
381	/*
382	 * XXX
383	 * The mount_mfs (newfs) command uses -o to select the
384	 * optimisation mode.  We don't pass the default "-o rw"
385	 * for that reason.
386	 */
387	if (flags & MNT_UPDATE)
388		optbuf = catopt(optbuf, "update");
389
390	argc = 0;
391	argv[argc++] = vfstype;
392	mangle(optbuf, &argc, argv);
393	argv[argc++] = spec;
394	argv[argc++] = name;
395	argv[argc] = NULL;
396
397	if (debug) {
398		(void)printf("exec: mount_%s", vfstype);
399		for (i = 1; i < argc; i++)
400			(void)printf(" %s", argv[i]);
401		(void)printf("\n");
402		return (0);
403	}
404
405	switch (pid = fork()) {
406	case -1:				/* Error. */
407		warn("fork");
408		free(optbuf);
409		return (1);
410	case 0:					/* Child. */
411		if (strcmp(vfstype, "ufs") == 0)
412			exit(mount_ufs(argc, (char * const *) argv));
413
414		/* Go find an executable. */
415		for (edir = edirs; *edir; edir++) {
416			(void)snprintf(execname,
417			    sizeof(execname), "%s/mount_%s", *edir, vfstype);
418			execv(execname, (char * const *)argv);
419		}
420		if (errno == ENOENT) {
421			int len = 0;
422			char *cp;
423			for (edir = edirs; *edir; edir++)
424				len += strlen(*edir) + 2;	/* ", " */
425			if ((cp = malloc(len)) == NULL) {
426				warn(NULL);
427				exit(1);
428			}
429			cp[0] = '\0';
430			for (edir = edirs; *edir; edir++) {
431				strcat(cp, *edir);
432				if (edir[1] != NULL)
433					strcat(cp, ", ");
434			}
435			warn("exec mount_%s not found in %s", vfstype, cp);
436		}
437		exit(1);
438		/* NOTREACHED */
439	default:				/* Parent. */
440		free(optbuf);
441
442		if (waitpid(pid, &status, 0) < 0) {
443			warn("waitpid");
444			return (1);
445		}
446
447		if (WIFEXITED(status)) {
448			if (WEXITSTATUS(status) != 0)
449				return (WEXITSTATUS(status));
450		} else if (WIFSIGNALED(status)) {
451			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
452			return (1);
453		}
454
455		if (verbose) {
456			if (statfs(name, &sf) < 0) {
457				warn("statfs %s", name);
458				return (1);
459			}
460			if (fstab_style)
461				putfsent(&sf);
462			else
463				prmount(&sf);
464		}
465		break;
466	}
467
468	return (0);
469}
470
471void
472prmount(sfp)
473	struct statfs *sfp;
474{
475	int flags;
476	struct opt *o;
477	struct passwd *pw;
478	int f;
479
480	(void)printf("%s on %s", sfp->f_mntfromname, sfp->f_mntonname);
481
482	flags = sfp->f_flags & MNT_VISFLAGMASK;
483	for (f = 0, o = optnames; flags && o->o_opt; o++)
484		if (flags & o->o_opt) {
485			(void)printf("%s%s", !f++ ? " (" : ", ", o->o_name);
486			flags &= ~o->o_opt;
487		}
488	if (sfp->f_owner) {
489		(void)printf("%smounted by ", !f++ ? " (" : ", ");
490		if ((pw = getpwuid(sfp->f_owner)) != NULL)
491			(void)printf("%s", pw->pw_name);
492		else
493			(void)printf("%d", sfp->f_owner);
494	}
495	(void)printf(f ? ")\n" : "\n");
496}
497
498struct statfs *
499getmntpt(name)
500	const char *name;
501{
502	struct statfs *mntbuf;
503	int i, mntsize;
504
505	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
506	for (i = 0; i < mntsize; i++)
507		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
508		    strcmp(mntbuf[i].f_mntonname, name) == 0)
509			return (&mntbuf[i]);
510	return (NULL);
511}
512
513char *
514catopt(s0, s1)
515	char *s0;
516	const char *s1;
517{
518	size_t i;
519	char *cp;
520
521	if (s0 && *s0) {
522		i = strlen(s0) + strlen(s1) + 1 + 1;
523		if ((cp = malloc(i)) == NULL)
524			err(1, NULL);
525		(void)snprintf(cp, i, "%s,%s", s0, s1);
526	} else
527		cp = strdup(s1);
528
529	if (s0)
530		free(s0);
531	return (cp);
532}
533
534void
535mangle(options, argcp, argv)
536	char *options;
537	int *argcp;
538	const char **argv;
539{
540	char *p, *s;
541	int argc;
542
543	argc = *argcp;
544	for (s = options; (p = strsep(&s, ",")) != NULL;)
545		if (*p != '\0')
546			if (*p == '-') {
547				argv[argc++] = p;
548				p = strchr(p, '=');
549				if (p) {
550					*p = '\0';
551					argv[argc++] = p+1;
552				}
553			} else if (strcmp(p, "rw") != 0) {
554				argv[argc++] = "-o";
555				argv[argc++] = p;
556			}
557
558	*argcp = argc;
559}
560
561void
562usage()
563{
564
565	(void)fprintf(stderr,
566		"usage: mount %s %s\n       mount %s\n       mount %s\n",
567		"[-dfpruvw] [-o options] [-t ufs | external_type]",
568			"special node",
569		"[-adfpruvw] [-t ufs | external_type]",
570		"[-dfpruvw] special | node");
571	exit(1);
572}
573
574void
575putfsent(ent)
576	const struct statfs *ent;
577{
578	struct fstab *fst;
579
580	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
581	    ent->f_fstypename, (ent->f_flags & MNT_RDONLY) ? "ro" : "rw");
582
583	/* XXX should use optnames[] - put shorter names in it. */
584	if (ent->f_flags & MNT_SYNCHRONOUS)
585		printf(",sync");
586	if (ent->f_flags & MNT_NOEXEC)
587		printf(",noexec");
588	if (ent->f_flags & MNT_NOSUID)
589		printf(",nosuid");
590	if (ent->f_flags & MNT_NODEV)
591		printf(",nodev");
592	if (ent->f_flags & MNT_UNION)
593		printf(",union");
594	if (ent->f_flags & MNT_ASYNC)
595		printf(",async");
596	if (ent->f_flags & MNT_NOATIME)
597		printf(",noatime");
598
599	if ((fst = getfsspec(ent->f_mntfromname)))
600		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
601	else if ((fst = getfsfile(ent->f_mntonname)))
602		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
603	else if (ent->f_type == MOUNT_UFS)
604		printf("\t1 1\n");
605	else
606		printf("\t0 0\n");
607}
608