xref: /freebsd/sbin/mount/mount.c (revision f8ea072a542112d5e0e74a2d6ecf75d967c3054c)
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static const char copyright[] =
32 "@(#) Copyright (c) 1980, 1989, 1993, 1994\n\
33 	The Regents of the University of California.  All rights reserved.\n";
34 #if 0
35 static char sccsid[] = "@(#)mount.c	8.25 (Berkeley) 5/8/95";
36 #endif
37 #endif /* not lint */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include <sys/param.h>
43 #include <sys/mount.h>
44 #include <sys/stat.h>
45 #include <sys/wait.h>
46 
47 #include <ctype.h>
48 #include <err.h>
49 #include <errno.h>
50 #include <fstab.h>
51 #include <paths.h>
52 #include <pwd.h>
53 #include <signal.h>
54 #include <stdint.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 #include <libutil.h>
60 
61 #include "extern.h"
62 #include "mntopts.h"
63 #include "pathnames.h"
64 
65 /* `meta' options */
66 #define MOUNT_META_OPTION_FSTAB		"fstab"
67 #define MOUNT_META_OPTION_CURRENT	"current"
68 
69 static int debug, fstab_style, verbose;
70 
71 struct cpa {
72 	char	**a;
73 	ssize_t	sz;
74 	int	c;
75 };
76 
77 char   *catopt(char *, const char *);
78 struct statfs *getmntpt(const char *);
79 int	hasopt(const char *, const char *);
80 int	ismounted(struct fstab *, struct statfs *, int);
81 int	isremountable(const char *);
82 void	mangle(char *, struct cpa *);
83 char   *update_options(char *, char *, int);
84 int	mountfs(const char *, const char *, const char *,
85 			int, const char *, const char *);
86 void	remopt(char *, const char *);
87 void	prmount(struct statfs *);
88 void	putfsent(struct statfs *);
89 void	usage(void);
90 char   *flags2opts(int);
91 
92 /* Map from mount options to printable formats. */
93 static struct opt {
94 	uint64_t o_opt;
95 	const char *o_name;
96 } optnames[] = {
97 	{ MNT_ASYNC,		"asynchronous" },
98 	{ MNT_EXPORTED,		"NFS exported" },
99 	{ MNT_LOCAL,		"local" },
100 	{ MNT_NOATIME,		"noatime" },
101 	{ MNT_NOEXEC,		"noexec" },
102 	{ MNT_NOSUID,		"nosuid" },
103 	{ MNT_NOSYMFOLLOW,	"nosymfollow" },
104 	{ MNT_QUOTA,		"with quotas" },
105 	{ MNT_RDONLY,		"read-only" },
106 	{ MNT_SYNCHRONOUS,	"synchronous" },
107 	{ MNT_UNION,		"union" },
108 	{ MNT_NOCLUSTERR,	"noclusterr" },
109 	{ MNT_NOCLUSTERW,	"noclusterw" },
110 	{ MNT_SUIDDIR,		"suiddir" },
111 	{ MNT_SOFTDEP,		"soft-updates" },
112 	{ MNT_SUJ,		"journaled soft-updates" },
113 	{ MNT_MULTILABEL,	"multilabel" },
114 	{ MNT_ACLS,		"acls" },
115 	{ MNT_NFS4ACLS,		"nfsv4acls" },
116 	{ MNT_GJOURNAL,		"gjournal" },
117 	{ 0, NULL }
118 };
119 
120 /*
121  * List of VFS types that can be remounted without becoming mounted on top
122  * of each other.
123  * XXX Is this list correct?
124  */
125 static const char *
126 remountable_fs_names[] = {
127 	"ufs", "ffs", "ext2fs",
128 	0
129 };
130 
131 static const char userquotaeq[] = "userquota=";
132 static const char groupquotaeq[] = "groupquota=";
133 
134 static char *mountprog = NULL;
135 
136 static int
137 use_mountprog(const char *vfstype)
138 {
139 	/* XXX: We need to get away from implementing external mount
140 	 *      programs for every filesystem, and move towards having
141 	 *	each filesystem properly implement the nmount() system call.
142 	 */
143 	unsigned int i;
144 	const char *fs[] = {
145 	"cd9660", "mfs", "msdosfs", "nfs",
146 	"nullfs", "oldnfs", "smbfs", "udf", "unionfs",
147 	NULL
148 	};
149 
150 	if (mountprog != NULL)
151 		return (1);
152 
153 	for (i = 0; fs[i] != NULL; ++i) {
154 		if (strcmp(vfstype, fs[i]) == 0)
155 			return (1);
156 	}
157 
158 	return (0);
159 }
160 
161 static int
162 exec_mountprog(const char *name, const char *execname, char *const argv[])
163 {
164 	pid_t pid;
165 	int status;
166 
167 	switch (pid = fork()) {
168 	case -1:				/* Error. */
169 		warn("fork");
170 		exit (1);
171 	case 0:					/* Child. */
172 		/* Go find an executable. */
173 		execvP(execname, _PATH_SYSPATH, argv);
174 		if (errno == ENOENT) {
175 			warn("exec %s not found", execname);
176 			if (execname[0] != '/') {
177 				warnx("in path: %s", _PATH_SYSPATH);
178 			}
179 		}
180 		exit(1);
181 	default:				/* Parent. */
182 		if (waitpid(pid, &status, 0) < 0) {
183 			warn("waitpid");
184 			return (1);
185 		}
186 
187 		if (WIFEXITED(status)) {
188 			if (WEXITSTATUS(status) != 0)
189 				return (WEXITSTATUS(status));
190 		} else if (WIFSIGNALED(status)) {
191 			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
192 			return (1);
193 		}
194 		break;
195 	}
196 
197 	return (0);
198 }
199 
200 static int
201 specified_ro(const char *arg)
202 {
203 	char *optbuf, *opt;
204 	int ret = 0;
205 
206 	optbuf = strdup(arg);
207 	if (optbuf == NULL)
208 		 err(1, NULL);
209 
210 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
211 		if (strcmp(opt, "ro") == 0) {
212 			ret = 1;
213 			break;
214 		}
215 	}
216 	free(optbuf);
217 	return (ret);
218 }
219 
220 static void
221 restart_mountd(void)
222 {
223 	struct pidfh *pfh;
224 	pid_t mountdpid;
225 
226 	pfh = pidfile_open(_PATH_MOUNTDPID, 0600, &mountdpid);
227 	if (pfh != NULL) {
228 		/* Mountd is not running. */
229 		pidfile_remove(pfh);
230 		return;
231 	}
232 	if (errno != EEXIST) {
233 		/* Cannot open pidfile for some reason. */
234 		return;
235 	}
236 	/* We have mountd(8) PID in mountdpid varible, let's signal it. */
237 	if (kill(mountdpid, SIGHUP) == -1)
238 		err(1, "signal mountd");
239 }
240 
241 int
242 main(int argc, char *argv[])
243 {
244 	const char *mntfromname, **vfslist, *vfstype;
245 	struct fstab *fs;
246 	struct statfs *mntbuf;
247 	int all, ch, i, init_flags, late, failok, mntsize, rval, have_fstab, ro;
248 	int onlylate;
249 	char *cp, *ep, *options;
250 
251 	all = init_flags = late = onlylate = 0;
252 	ro = 0;
253 	options = NULL;
254 	vfslist = NULL;
255 	vfstype = "ufs";
256 	while ((ch = getopt(argc, argv, "adF:fLlo:prt:uvw")) != -1)
257 		switch (ch) {
258 		case 'a':
259 			all = 1;
260 			break;
261 		case 'd':
262 			debug = 1;
263 			break;
264 		case 'F':
265 			setfstab(optarg);
266 			break;
267 		case 'f':
268 			init_flags |= MNT_FORCE;
269 			break;
270 		case 'L':
271 			onlylate = 1;
272 			late = 1;
273 			break;
274 		case 'l':
275 			late = 1;
276 			break;
277 		case 'o':
278 			if (*optarg) {
279 				options = catopt(options, optarg);
280 				if (specified_ro(optarg))
281 					ro = 1;
282 			}
283 			break;
284 		case 'p':
285 			fstab_style = 1;
286 			verbose = 1;
287 			break;
288 		case 'r':
289 			options = catopt(options, "ro");
290 			ro = 1;
291 			break;
292 		case 't':
293 			if (vfslist != NULL)
294 				errx(1, "only one -t option may be specified");
295 			vfslist = makevfslist(optarg);
296 			vfstype = optarg;
297 			break;
298 		case 'u':
299 			init_flags |= MNT_UPDATE;
300 			break;
301 		case 'v':
302 			verbose = 1;
303 			break;
304 		case 'w':
305 			options = catopt(options, "noro");
306 			break;
307 		case '?':
308 		default:
309 			usage();
310 			/* NOTREACHED */
311 		}
312 	argc -= optind;
313 	argv += optind;
314 
315 #define	BADTYPE(type)							\
316 	(strcmp(type, FSTAB_RO) &&					\
317 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
318 
319 	if ((init_flags & MNT_UPDATE) && (ro == 0))
320 		options = catopt(options, "noro");
321 
322 	rval = 0;
323 	switch (argc) {
324 	case 0:
325 		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
326 			err(1, "getmntinfo");
327 		if (all) {
328 			while ((fs = getfsent()) != NULL) {
329 				if (BADTYPE(fs->fs_type))
330 					continue;
331 				if (checkvfsname(fs->fs_vfstype, vfslist))
332 					continue;
333 				if (hasopt(fs->fs_mntops, "noauto"))
334 					continue;
335 				if (!hasopt(fs->fs_mntops, "late") && onlylate)
336 					continue;
337 				if (hasopt(fs->fs_mntops, "late") && !late)
338 					continue;
339 				if (hasopt(fs->fs_mntops, "failok"))
340 					failok = 1;
341 				else
342 					failok = 0;
343 				if (!(init_flags & MNT_UPDATE) &&
344 				    ismounted(fs, mntbuf, mntsize))
345 					continue;
346 				options = update_options(options, fs->fs_mntops,
347 				    mntbuf->f_flags);
348 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
349 				    fs->fs_file, init_flags, options,
350 				    fs->fs_mntops) && !failok)
351 					rval = 1;
352 			}
353 		} else if (fstab_style) {
354 			for (i = 0; i < mntsize; i++) {
355 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
356 					continue;
357 				putfsent(&mntbuf[i]);
358 			}
359 		} else {
360 			for (i = 0; i < mntsize; i++) {
361 				if (checkvfsname(mntbuf[i].f_fstypename,
362 				    vfslist))
363 					continue;
364 				if (!verbose &&
365 				    (mntbuf[i].f_flags & MNT_IGNORE) != 0)
366 					continue;
367 				prmount(&mntbuf[i]);
368 			}
369 		}
370 		exit(rval);
371 	case 1:
372 		if (vfslist != NULL)
373 			usage();
374 
375 		rmslashes(*argv, *argv);
376 		if (init_flags & MNT_UPDATE) {
377 			mntfromname = NULL;
378 			have_fstab = 0;
379 			if ((mntbuf = getmntpt(*argv)) == NULL)
380 				errx(1, "not currently mounted %s", *argv);
381 			/*
382 			 * Only get the mntflags from fstab if both mntpoint
383 			 * and mntspec are identical. Also handle the special
384 			 * case where just '/' is mounted and 'spec' is not
385 			 * identical with the one from fstab ('/dev' is missing
386 			 * in the spec-string at boot-time).
387 			 */
388 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
389 				if (strcmp(fs->fs_spec,
390 				    mntbuf->f_mntfromname) == 0 &&
391 				    strcmp(fs->fs_file,
392 				    mntbuf->f_mntonname) == 0) {
393 					have_fstab = 1;
394 					mntfromname = mntbuf->f_mntfromname;
395 				} else if (argv[0][0] == '/' &&
396 				    argv[0][1] == '\0') {
397 					fs = getfsfile("/");
398 					have_fstab = 1;
399 					mntfromname = fs->fs_spec;
400 				}
401 			}
402 			if (have_fstab) {
403 				options = update_options(options, fs->fs_mntops,
404 				    mntbuf->f_flags);
405 			} else {
406 				mntfromname = mntbuf->f_mntfromname;
407 				options = update_options(options, NULL,
408 				    mntbuf->f_flags);
409 			}
410 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
411 			    mntbuf->f_mntonname, init_flags, options, 0);
412 			break;
413 		}
414 		if ((fs = getfsfile(*argv)) == NULL &&
415 		    (fs = getfsspec(*argv)) == NULL)
416 			errx(1, "%s: unknown special file or file system",
417 			    *argv);
418 		if (BADTYPE(fs->fs_type))
419 			errx(1, "%s has unknown file system type",
420 			    *argv);
421 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
422 		    init_flags, options, fs->fs_mntops);
423 		break;
424 	case 2:
425 		/*
426 		 * If -t flag has not been specified, the path cannot be
427 		 * found, spec contains either a ':' or a '@', then assume
428 		 * that an NFS file system is being specified ala Sun.
429 		 * Check if the hostname contains only allowed characters
430 		 * to reduce false positives.  IPv6 addresses containing
431 		 * ':' will be correctly parsed only if the separator is '@'.
432 		 * The definition of a valid hostname is taken from RFC 1034.
433 		 */
434 		if (vfslist == NULL && ((ep = strchr(argv[0], '@')) != NULL ||
435 		    (ep = strchr(argv[0], ':')) != NULL)) {
436 			if (*ep == '@') {
437 				cp = ep + 1;
438 				ep = cp + strlen(cp);
439 			} else
440 				cp = argv[0];
441 			while (cp != ep) {
442 				if (!isdigit(*cp) && !isalpha(*cp) &&
443 				    *cp != '.' && *cp != '-' && *cp != ':')
444 					break;
445 				cp++;
446 			}
447 			if (cp == ep)
448 				vfstype = "nfs";
449 		}
450 		rval = mountfs(vfstype,
451 		    argv[0], argv[1], init_flags, options, NULL);
452 		break;
453 	default:
454 		usage();
455 		/* NOTREACHED */
456 	}
457 
458 	/*
459 	 * If the mount was successfully, and done by root, tell mountd the
460 	 * good news.
461 	 */
462 	if (rval == 0 && getuid() == 0)
463 		restart_mountd();
464 
465 	exit(rval);
466 }
467 
468 int
469 ismounted(struct fstab *fs, struct statfs *mntbuf, int mntsize)
470 {
471 	char realfsfile[PATH_MAX];
472 	int i;
473 
474 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
475 		/* the root file system can always be remounted */
476 		return (0);
477 
478 	/* The user may have specified a symlink in fstab, resolve the path */
479 	if (realpath(fs->fs_file, realfsfile) == NULL) {
480 		/* Cannot resolve the path, use original one */
481 		strlcpy(realfsfile, fs->fs_file, sizeof(realfsfile));
482 	}
483 
484 	for (i = mntsize - 1; i >= 0; --i)
485 		if (strcmp(realfsfile, mntbuf[i].f_mntonname) == 0 &&
486 		    (!isremountable(fs->fs_vfstype) ||
487 		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
488 			return (1);
489 	return (0);
490 }
491 
492 int
493 isremountable(const char *vfsname)
494 {
495 	const char **cp;
496 
497 	for (cp = remountable_fs_names; *cp; cp++)
498 		if (strcmp(*cp, vfsname) == 0)
499 			return (1);
500 	return (0);
501 }
502 
503 int
504 hasopt(const char *mntopts, const char *option)
505 {
506 	int negative, found;
507 	char *opt, *optbuf;
508 
509 	if (option[0] == 'n' && option[1] == 'o') {
510 		negative = 1;
511 		option += 2;
512 	} else
513 		negative = 0;
514 	optbuf = strdup(mntopts);
515 	found = 0;
516 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
517 		if (opt[0] == 'n' && opt[1] == 'o') {
518 			if (!strcasecmp(opt + 2, option))
519 				found = negative;
520 		} else if (!strcasecmp(opt, option))
521 			found = !negative;
522 	}
523 	free(optbuf);
524 	return (found);
525 }
526 
527 static void
528 append_arg(struct cpa *sa, char *arg)
529 {
530 	if (sa->c + 1 == sa->sz) {
531 		sa->sz = sa->sz == 0 ? 8 : sa->sz * 2;
532 		sa->a = realloc(sa->a, sizeof(sa->a) * sa->sz);
533 		if (sa->a == NULL)
534 			errx(1, "realloc failed");
535 	}
536 	sa->a[++sa->c] = arg;
537 }
538 
539 int
540 mountfs(const char *vfstype, const char *spec, const char *name, int flags,
541 	const char *options, const char *mntopts)
542 {
543 	struct statfs sf;
544 	int i, ret;
545 	char *optbuf, execname[PATH_MAX], mntpath[PATH_MAX];
546 	static struct cpa mnt_argv;
547 
548 	/* resolve the mountpoint with realpath(3) */
549 	if (checkpath(name, mntpath) != 0) {
550 		warn("%s", mntpath);
551 		return (1);
552 	}
553 	name = mntpath;
554 
555 	if (mntopts == NULL)
556 		mntopts = "";
557 	optbuf = catopt(strdup(mntopts), options);
558 
559 	if (strcmp(name, "/") == 0)
560 		flags |= MNT_UPDATE;
561 	if (flags & MNT_FORCE)
562 		optbuf = catopt(optbuf, "force");
563 	if (flags & MNT_RDONLY)
564 		optbuf = catopt(optbuf, "ro");
565 	/*
566 	 * XXX
567 	 * The mount_mfs (newfs) command uses -o to select the
568 	 * optimization mode.  We don't pass the default "-o rw"
569 	 * for that reason.
570 	 */
571 	if (flags & MNT_UPDATE)
572 		optbuf = catopt(optbuf, "update");
573 
574 	/* Compatibility glue. */
575 	if (strcmp(vfstype, "msdos") == 0) {
576 		warnx(
577 		    "Using \"-t msdosfs\", since \"-t msdos\" is deprecated.");
578 		vfstype = "msdosfs";
579 	}
580 
581 	/* Construct the name of the appropriate mount command */
582 	(void)snprintf(execname, sizeof(execname), "mount_%s", vfstype);
583 
584 	mnt_argv.c = -1;
585 	append_arg(&mnt_argv, execname);
586 	mangle(optbuf, &mnt_argv);
587 	if (mountprog != NULL)
588 		strcpy(execname, mountprog);
589 
590 	append_arg(&mnt_argv, strdup(spec));
591 	append_arg(&mnt_argv, strdup(name));
592 	append_arg(&mnt_argv, NULL);
593 
594 	if (debug) {
595 		if (use_mountprog(vfstype))
596 			printf("exec: %s", execname);
597 		else
598 			printf("mount -t %s", vfstype);
599 		for (i = 1; i < mnt_argv.c; i++)
600 			(void)printf(" %s", mnt_argv.a[i]);
601 		(void)printf("\n");
602 		free(optbuf);
603 		free(mountprog);
604 		mountprog = NULL;
605 		return (0);
606 	}
607 
608 	if (use_mountprog(vfstype)) {
609 		ret = exec_mountprog(name, execname, mnt_argv.a);
610 	} else {
611 		ret = mount_fs(vfstype, mnt_argv.c, mnt_argv.a);
612 	}
613 
614 	free(optbuf);
615 	free(mountprog);
616 	mountprog = NULL;
617 
618 	if (verbose) {
619 		if (statfs(name, &sf) < 0) {
620 			warn("statfs %s", name);
621 			return (1);
622 		}
623 		if (fstab_style)
624 			putfsent(&sf);
625 		else
626 			prmount(&sf);
627 	}
628 
629 	return (ret);
630 }
631 
632 void
633 prmount(struct statfs *sfp)
634 {
635 	uint64_t flags;
636 	unsigned int i;
637 	struct opt *o;
638 	struct passwd *pw;
639 
640 	(void)printf("%s on %s (%s", sfp->f_mntfromname, sfp->f_mntonname,
641 	    sfp->f_fstypename);
642 
643 	flags = sfp->f_flags & MNT_VISFLAGMASK;
644 	for (o = optnames; flags != 0 && o->o_opt != 0; o++)
645 		if (flags & o->o_opt) {
646 			(void)printf(", %s", o->o_name);
647 			flags &= ~o->o_opt;
648 		}
649 	/*
650 	 * Inform when file system is mounted by an unprivileged user
651 	 * or privileged non-root user.
652 	 */
653 	if ((flags & MNT_USER) != 0 || sfp->f_owner != 0) {
654 		(void)printf(", mounted by ");
655 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
656 			(void)printf("%s", pw->pw_name);
657 		else
658 			(void)printf("%d", sfp->f_owner);
659 	}
660 	if (verbose) {
661 		if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
662 			(void)printf(", writes: sync %ju async %ju",
663 			    (uintmax_t)sfp->f_syncwrites,
664 			    (uintmax_t)sfp->f_asyncwrites);
665 		if (sfp->f_syncreads != 0 || sfp->f_asyncreads != 0)
666 			(void)printf(", reads: sync %ju async %ju",
667 			    (uintmax_t)sfp->f_syncreads,
668 			    (uintmax_t)sfp->f_asyncreads);
669 		if (sfp->f_fsid.val[0] != 0 || sfp->f_fsid.val[1] != 0) {
670 			printf(", fsid ");
671 			for (i = 0; i < sizeof(sfp->f_fsid); i++)
672 				printf("%02x", ((u_char *)&sfp->f_fsid)[i]);
673 		}
674 	}
675 	(void)printf(")\n");
676 }
677 
678 struct statfs *
679 getmntpt(const char *name)
680 {
681 	struct statfs *mntbuf;
682 	int i, mntsize;
683 
684 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
685 	for (i = mntsize - 1; i >= 0; i--) {
686 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
687 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
688 			return (&mntbuf[i]);
689 	}
690 	return (NULL);
691 }
692 
693 char *
694 catopt(char *s0, const char *s1)
695 {
696 	size_t i;
697 	char *cp;
698 
699 	if (s1 == NULL || *s1 == '\0')
700 		return (s0);
701 
702 	if (s0 && *s0) {
703 		i = strlen(s0) + strlen(s1) + 1 + 1;
704 		if ((cp = malloc(i)) == NULL)
705 			errx(1, "malloc failed");
706 		(void)snprintf(cp, i, "%s,%s", s0, s1);
707 	} else
708 		cp = strdup(s1);
709 
710 	if (s0)
711 		free(s0);
712 	return (cp);
713 }
714 
715 void
716 mangle(char *options, struct cpa *a)
717 {
718 	char *p, *s, *val;
719 
720 	for (s = options; (p = strsep(&s, ",")) != NULL;)
721 		if (*p != '\0') {
722 			if (strcmp(p, "noauto") == 0) {
723 				/*
724 				 * Do not pass noauto option to nmount().
725 				 * or external mount program.  noauto is
726 				 * only used to prevent mounting a filesystem
727 				 * when 'mount -a' is specified, and is
728 				 * not a real mount option.
729 				 */
730 				continue;
731 			} else if (strcmp(p, "late") == 0) {
732 				/*
733 				 * "late" is used to prevent certain file
734 				 * systems from being mounted before late
735 				 * in the boot cycle; for instance,
736 				 * loopback NFS mounts can't be mounted
737 				 * before mountd starts.
738 				 */
739 				continue;
740 			} else if (strcmp(p, "failok") == 0) {
741 				/*
742 				 * "failok" is used to prevent certain file
743 				 * systems from being causing the system to
744 				 * drop into single user mode in the boot
745 				 * cycle, and is not a real mount option.
746 				 */
747 				continue;
748 			} else if (strncmp(p, "mountprog", 9) == 0) {
749 				/*
750 				 * "mountprog" is used to force the use of
751 				 * userland mount programs.
752 				 */
753 				val = strchr(p, '=');
754                         	if (val != NULL) {
755                                 	++val;
756 					if (*val != '\0')
757 						mountprog = strdup(val);
758 				}
759 
760 				if (mountprog == NULL) {
761 					errx(1, "Need value for -o mountprog");
762 				}
763 				continue;
764 			} else if (strcmp(p, "userquota") == 0) {
765 				continue;
766 			} else if (strncmp(p, userquotaeq,
767 			    sizeof(userquotaeq) - 1) == 0) {
768 				continue;
769 			} else if (strcmp(p, "groupquota") == 0) {
770 				continue;
771 			} else if (strncmp(p, groupquotaeq,
772 			    sizeof(groupquotaeq) - 1) == 0) {
773 				continue;
774 			} else if (*p == '-') {
775 				append_arg(a, p);
776 				p = strchr(p, '=');
777 				if (p != NULL) {
778 					*p = '\0';
779 					append_arg(a, p + 1);
780 				}
781 			} else {
782 				append_arg(a, strdup("-o"));
783 				append_arg(a, p);
784 			}
785 		}
786 }
787 
788 
789 char *
790 update_options(char *opts, char *fstab, int curflags)
791 {
792 	char *o, *p;
793 	char *cur;
794 	char *expopt, *newopt, *tmpopt;
795 
796 	if (opts == NULL)
797 		return (strdup(""));
798 
799 	/* remove meta options from list */
800 	remopt(fstab, MOUNT_META_OPTION_FSTAB);
801 	remopt(fstab, MOUNT_META_OPTION_CURRENT);
802 	cur = flags2opts(curflags);
803 
804 	/*
805 	 * Expand all meta-options passed to us first.
806 	 */
807 	expopt = NULL;
808 	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
809 		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
810 			expopt = catopt(expopt, fstab);
811 		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
812 			expopt = catopt(expopt, cur);
813 		else
814 			expopt = catopt(expopt, o);
815 	}
816 	free(cur);
817 	free(opts);
818 
819 	/*
820 	 * Remove previous contradictory arguments. Given option "foo" we
821 	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
822 	 * and "foo" - so we can deal with possible options like "notice".
823 	 */
824 	newopt = NULL;
825 	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
826 		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
827 			errx(1, "malloc failed");
828 
829 		strcpy(tmpopt, "no");
830 		strcat(tmpopt, o);
831 		remopt(newopt, tmpopt);
832 		free(tmpopt);
833 
834 		if (strncmp("no", o, 2) == 0)
835 			remopt(newopt, o+2);
836 
837 		newopt = catopt(newopt, o);
838 	}
839 	free(expopt);
840 
841 	return (newopt);
842 }
843 
844 void
845 remopt(char *string, const char *opt)
846 {
847 	char *o, *p, *r;
848 
849 	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
850 		return;
851 
852 	r = string;
853 
854 	for (p = string; (o = strsep(&p, ",")) != NULL;) {
855 		if (strcmp(opt, o) != 0) {
856 			if (*r == ',' && *o != '\0')
857 				r++;
858 			while ((*r++ = *o++) != '\0')
859 			    ;
860 			*--r = ',';
861 		}
862 	}
863 	*r = '\0';
864 }
865 
866 void
867 usage(void)
868 {
869 
870 	(void)fprintf(stderr, "%s\n%s\n%s\n",
871 "usage: mount [-adflpruvw] [-F fstab] [-o options] [-t ufs | external_type]",
872 "       mount [-dfpruvw] special | node",
873 "       mount [-dfpruvw] [-o options] [-t ufs | external_type] special node");
874 	exit(1);
875 }
876 
877 void
878 putfsent(struct statfs *ent)
879 {
880 	struct fstab *fst;
881 	char *opts, *rw;
882 	int l;
883 
884 	opts = NULL;
885 	/* flags2opts() doesn't return the "rw" option. */
886 	if ((ent->f_flags & MNT_RDONLY) != 0)
887 		rw = NULL;
888 	else
889 		rw = catopt(NULL, "rw");
890 
891 	opts = flags2opts(ent->f_flags);
892 	opts = catopt(rw, opts);
893 
894 	if (strncmp(ent->f_mntfromname, "<below>", 7) == 0 ||
895 	    strncmp(ent->f_mntfromname, "<above>", 7) == 0) {
896 		strcpy(ent->f_mntfromname, (strnstr(ent->f_mntfromname, ":", 8)
897 		    +1));
898 	}
899 
900 	l = strlen(ent->f_mntfromname);
901 	printf("%s%s%s%s", ent->f_mntfromname,
902 	    l < 8 ? "\t" : "",
903 	    l < 16 ? "\t" : "",
904 	    l < 24 ? "\t" : " ");
905 	l = strlen(ent->f_mntonname);
906 	printf("%s%s%s%s", ent->f_mntonname,
907 	    l < 8 ? "\t" : "",
908 	    l < 16 ? "\t" : "",
909 	    l < 24 ? "\t" : " ");
910 	printf("%s\t", ent->f_fstypename);
911 	l = strlen(opts);
912 	printf("%s%s", opts,
913 	    l < 8 ? "\t" : " ");
914 	free(opts);
915 
916 	if ((fst = getfsspec(ent->f_mntfromname)))
917 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
918 	else if ((fst = getfsfile(ent->f_mntonname)))
919 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
920 	else if (strcmp(ent->f_fstypename, "ufs") == 0) {
921 		if (strcmp(ent->f_mntonname, "/") == 0)
922 			printf("\t1 1\n");
923 		else
924 			printf("\t2 2\n");
925 	} else
926 		printf("\t0 0\n");
927 }
928 
929 
930 char *
931 flags2opts(int flags)
932 {
933 	char *res;
934 
935 	res = NULL;
936 
937 	if (flags & MNT_RDONLY)		res = catopt(res, "ro");
938 	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
939 	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
940 	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
941 	if (flags & MNT_UNION)		res = catopt(res, "union");
942 	if (flags & MNT_ASYNC)		res = catopt(res, "async");
943 	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
944 	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
945 	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
946 	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
947 	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
948 	if (flags & MNT_MULTILABEL)	res = catopt(res, "multilabel");
949 	if (flags & MNT_ACLS)		res = catopt(res, "acls");
950 	if (flags & MNT_NFS4ACLS)	res = catopt(res, "nfsv4acls");
951 
952 	return (res);
953 }
954