xref: /freebsd/sbin/mount/mount.c (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1989, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/param.h>
33 #define _WANT_MNTOPTNAMES
34 #include <sys/mount.h>
35 #include <sys/stat.h>
36 #include <sys/wait.h>
37 
38 #include <ctype.h>
39 #include <err.h>
40 #include <errno.h>
41 #include <fstab.h>
42 #include <paths.h>
43 #include <pwd.h>
44 #include <signal.h>
45 #include <stdint.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <libutil.h>
51 #include <libxo/xo.h>
52 
53 #include "extern.h"
54 #include "mntopts.h"
55 #include "pathnames.h"
56 
57 #define EXIT(a) {			\
58 	xo_close_container("mount");	\
59 	xo_finish();			\
60 	exit(a);			\
61 	}
62 
63 /* `meta' options */
64 #define MOUNT_META_OPTION_FSTAB		"fstab"
65 #define MOUNT_META_OPTION_CURRENT	"current"
66 
67 static int debug, fstab_style, verbose;
68 
69 struct cpa {
70 	char	**a;
71 	ssize_t	sz;
72 	int	c;
73 };
74 
75 char   *catopt(char *, const char *);
76 int	hasopt(const char *, const char *);
77 int	ismounted(struct fstab *, struct statfs *, int);
78 int	isremountable(const char *);
79 int	allow_file_mount(const char *);
80 void	mangle(char *, struct cpa *);
81 char   *update_options(char *, char *, int);
82 int	mountfs(const char *, const char *, const char *,
83 			int, const char *, const char *);
84 void	remopt(char *, const char *);
85 void	prmount(struct statfs *);
86 void	putfsent(struct statfs *);
87 void	usage(void);
88 char   *flags2opts(int);
89 
90 /* Map from mount options to printable formats. */
91 static struct mntoptnames optnames[] = {
92 	MNTOPT_NAMES
93 };
94 
95 /*
96  * List of VFS types that can be remounted without becoming mounted on top
97  * of each other.
98  * XXX Is this list correct?
99  */
100 static const char *
101 remountable_fs_names[] = {
102 	"ufs", "ffs", "ext2fs",
103 	0
104 };
105 
106 static const char userquotaeq[] = "userquota=";
107 static const char groupquotaeq[] = "groupquota=";
108 
109 static char *mountprog = NULL;
110 
111 static int
112 use_mountprog(const char *vfstype)
113 {
114 	/* XXX: We need to get away from implementing external mount
115 	 *      programs for every filesystem, and move towards having
116 	 *	each filesystem properly implement the nmount() system call.
117 	 */
118 	unsigned int i;
119 	const char *fs[] = {
120 	"cd9660", "mfs", "msdosfs", "nfs",
121 	"nullfs", "smbfs", "udf", "unionfs",
122 	NULL
123 	};
124 
125 	if (mountprog != NULL)
126 		return (1);
127 
128 	for (i = 0; fs[i] != NULL; ++i) {
129 		if (strcmp(vfstype, fs[i]) == 0)
130 			return (1);
131 	}
132 
133 	return (0);
134 }
135 
136 static int
137 exec_mountprog(const char *name, const char *execname, char *const argv[])
138 {
139 	pid_t pid;
140 	int status;
141 
142 	switch (pid = fork()) {
143 	case -1:				/* Error. */
144 		xo_warn("fork");
145 		EXIT(1);
146 	case 0:					/* Child. */
147 		/* Go find an executable. */
148 		execvP(execname, _PATH_SYSPATH, argv);
149 		if (errno == ENOENT) {
150 			xo_warn("exec %s not found", execname);
151 			if (execname[0] != '/') {
152 				xo_warnx("in path: %s", _PATH_SYSPATH);
153 			}
154 		}
155 		EXIT(1);
156 	default:				/* Parent. */
157 		if (waitpid(pid, &status, 0) < 0) {
158 			xo_warn("waitpid");
159 			return (1);
160 		}
161 
162 		if (WIFEXITED(status)) {
163 			if (WEXITSTATUS(status) != 0)
164 				return (WEXITSTATUS(status));
165 		} else if (WIFSIGNALED(status)) {
166 			xo_warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
167 			return (1);
168 		}
169 		break;
170 	}
171 
172 	return (0);
173 }
174 
175 static int
176 specified_ro(const char *arg)
177 {
178 	char *optbuf, *opt;
179 	int ret = 0;
180 
181 	optbuf = strdup(arg);
182 	if (optbuf == NULL)
183 		 xo_err(1, "strdup failed");
184 
185 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
186 		if (strcmp(opt, "ro") == 0) {
187 			ret = 1;
188 			break;
189 		}
190 	}
191 	free(optbuf);
192 	return (ret);
193 }
194 
195 static void
196 restart_mountd(void)
197 {
198 
199 	pidfile_signal(_PATH_MOUNTDPID, SIGHUP, NULL);
200 }
201 
202 int
203 main(int argc, char *argv[])
204 {
205 	const char *mntfromname, **vfslist, *vfstype;
206 	struct fstab *fs;
207 	struct statfs *mntbuf;
208 	int all, ch, i, init_flags, late, failok, mntsize, rval, have_fstab, ro;
209 	int onlylate;
210 	char *cp, *ep, *options;
211 
212 	all = init_flags = late = onlylate = 0;
213 	ro = 0;
214 	options = NULL;
215 	vfslist = NULL;
216 	vfstype = "ufs";
217 
218 	argc = xo_parse_args(argc, argv);
219 	if (argc < 0)
220 		exit(1);
221 	xo_open_container("mount");
222 
223 	while ((ch = getopt(argc, argv, "adF:fLlno:prt:uvw")) != -1)
224 		switch (ch) {
225 		case 'a':
226 			all = 1;
227 			break;
228 		case 'd':
229 			debug = 1;
230 			break;
231 		case 'F':
232 			setfstab(optarg);
233 			break;
234 		case 'f':
235 			init_flags |= MNT_FORCE;
236 			break;
237 		case 'L':
238 			onlylate = 1;
239 			late = 1;
240 			break;
241 		case 'l':
242 			late = 1;
243 			break;
244 		case 'n':
245 			/* For compatibility with the Linux version of mount. */
246 			break;
247 		case 'o':
248 			if (*optarg) {
249 				options = catopt(options, optarg);
250 				if (specified_ro(optarg))
251 					ro = 1;
252 			}
253 			break;
254 		case 'p':
255 			fstab_style = 1;
256 			verbose = 1;
257 			break;
258 		case 'r':
259 			options = catopt(options, "ro");
260 			ro = 1;
261 			break;
262 		case 't':
263 			if (vfslist != NULL)
264 				xo_errx(1, "only one -t option may be specified");
265 			vfslist = makevfslist(optarg);
266 			vfstype = optarg;
267 			break;
268 		case 'u':
269 			init_flags |= MNT_UPDATE;
270 			break;
271 		case 'v':
272 			verbose = 1;
273 			break;
274 		case 'w':
275 			options = catopt(options, "noro");
276 			break;
277 		case '?':
278 		default:
279 			usage();
280 			/* NOTREACHED */
281 		}
282 	argc -= optind;
283 	argv += optind;
284 
285 #define	BADTYPE(type)							\
286 	(strcmp(type, FSTAB_RO) &&					\
287 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
288 
289 	if ((init_flags & MNT_UPDATE) && (ro == 0))
290 		options = catopt(options, "noro");
291 
292 	rval = 0;
293 	switch (argc) {
294 	case 0:
295 		if ((mntsize = getmntinfo(&mntbuf,
296 		     verbose ? MNT_WAIT : MNT_NOWAIT)) == 0)
297 			xo_err(1, "getmntinfo");
298 		if (all) {
299 			while ((fs = getfsent()) != NULL) {
300 				if (BADTYPE(fs->fs_type))
301 					continue;
302 				if (checkvfsname(fs->fs_vfstype, vfslist))
303 					continue;
304 				if (hasopt(fs->fs_mntops, "noauto"))
305 					continue;
306 				if (!hasopt(fs->fs_mntops, "late") && onlylate)
307 					continue;
308 				if (hasopt(fs->fs_mntops, "late") && !late)
309 					continue;
310 				if (hasopt(fs->fs_mntops, "failok"))
311 					failok = 1;
312 				else
313 					failok = 0;
314 				if (!(init_flags & MNT_UPDATE) &&
315 				    !hasopt(fs->fs_mntops, "update") &&
316 				    ismounted(fs, mntbuf, mntsize))
317 					continue;
318 				options = update_options(options, fs->fs_mntops,
319 				    mntbuf->f_flags);
320 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
321 				    fs->fs_file, init_flags, options,
322 				    fs->fs_mntops) && !failok)
323 					rval = 1;
324 			}
325 		} else if (fstab_style) {
326 			xo_open_list("fstab");
327 			for (i = 0; i < mntsize; i++) {
328 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
329 					continue;
330 				xo_open_instance("fstab");
331 				putfsent(&mntbuf[i]);
332 				xo_close_instance("fstab");
333 			}
334 			xo_close_list("fstab");
335 		} else {
336 			xo_open_list("mounted");
337 			for (i = 0; i < mntsize; i++) {
338 				if (checkvfsname(mntbuf[i].f_fstypename,
339 				    vfslist))
340 					continue;
341 				if (!verbose &&
342 				    (mntbuf[i].f_flags & MNT_IGNORE) != 0)
343 					continue;
344 				xo_open_instance("mounted");
345 				prmount(&mntbuf[i]);
346 				xo_close_instance("mounted");
347 			}
348 			xo_close_list("mounted");
349 		}
350 		EXIT(rval);
351 	case 1:
352 		if (vfslist != NULL)
353 			usage();
354 
355 		rmslashes(*argv, *argv);
356 		if (init_flags & MNT_UPDATE) {
357 			mntfromname = NULL;
358 			have_fstab = 0;
359 			if ((mntbuf = getmntpoint(*argv)) == NULL)
360 				xo_errx(1, "not currently mounted %s", *argv);
361 			/*
362 			 * Only get the mntflags from fstab if both mntpoint
363 			 * and mntspec are identical. Also handle the special
364 			 * case where just '/' is mounted and 'spec' is not
365 			 * identical with the one from fstab ('/dev' is missing
366 			 * in the spec-string at boot-time).
367 			 */
368 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
369 				if (strcmp(fs->fs_spec,
370 				    mntbuf->f_mntfromname) == 0 &&
371 				    strcmp(fs->fs_file,
372 				    mntbuf->f_mntonname) == 0) {
373 					have_fstab = 1;
374 					mntfromname = mntbuf->f_mntfromname;
375 				} else if (argv[0][0] == '/' &&
376 				    argv[0][1] == '\0' &&
377 				    strcmp(fs->fs_vfstype,
378 				    mntbuf->f_fstypename) == 0) {
379 					fs = getfsfile("/");
380 					have_fstab = 1;
381 					mntfromname = fs->fs_spec;
382 				}
383 			}
384 			if (have_fstab) {
385 				options = update_options(options, fs->fs_mntops,
386 				    mntbuf->f_flags);
387 			} else {
388 				mntfromname = mntbuf->f_mntfromname;
389 				options = update_options(options, NULL,
390 				    mntbuf->f_flags);
391 			}
392 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
393 			    mntbuf->f_mntonname, init_flags, options, 0);
394 			break;
395 		}
396 		if ((fs = getfsfile(*argv)) == NULL &&
397 		    (fs = getfsspec(*argv)) == NULL)
398 			xo_errx(1, "%s: unknown special file or file system",
399 			    *argv);
400 		if (BADTYPE(fs->fs_type))
401 			xo_errx(1, "%s has unknown file system type",
402 			    *argv);
403 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
404 		    init_flags, options, fs->fs_mntops);
405 		break;
406 	case 2:
407 		/*
408 		 * If -t flag has not been specified, the path cannot be
409 		 * found, spec contains either a ':' or a '@', then assume
410 		 * that an NFS file system is being specified ala Sun.
411 		 * Check if the hostname contains only allowed characters
412 		 * to reduce false positives.  IPv6 addresses containing
413 		 * ':' will be correctly parsed only if the separator is '@'.
414 		 * The definition of a valid hostname is taken from RFC 1034.
415 		 */
416 		if (vfslist == NULL && ((ep = strchr(argv[0], '@')) != NULL ||
417 		    (ep = strchr(argv[0], ':')) != NULL)) {
418 			if (*ep == '@') {
419 				cp = ep + 1;
420 				ep = cp + strlen(cp);
421 			} else
422 				cp = argv[0];
423 			while (cp != ep) {
424 				if (!isdigit(*cp) && !isalpha(*cp) &&
425 				    *cp != '.' && *cp != '-' && *cp != ':')
426 					break;
427 				cp++;
428 			}
429 			if (cp == ep)
430 				vfstype = "nfs";
431 		}
432 		rval = mountfs(vfstype,
433 		    argv[0], argv[1], init_flags, options, NULL);
434 		break;
435 	default:
436 		usage();
437 		/* NOTREACHED */
438 	}
439 
440 	/*
441 	 * If the mount was successfully, and done by root, tell mountd the
442 	 * good news.
443 	 */
444 	if (rval == 0 && getuid() == 0)
445 		restart_mountd();
446 
447 	EXIT(rval);
448 }
449 
450 int
451 ismounted(struct fstab *fs, struct statfs *mntbuf, int mntsize)
452 {
453 	char realfsfile[PATH_MAX];
454 	int i;
455 
456 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
457 		/* the root file system can always be remounted */
458 		return (0);
459 
460 	/* The user may have specified a symlink in fstab, resolve the path */
461 	if (realpath(fs->fs_file, realfsfile) == NULL) {
462 		/* Cannot resolve the path, use original one */
463 		strlcpy(realfsfile, fs->fs_file, sizeof(realfsfile));
464 	}
465 
466 	/*
467 	 * Consider the filesystem to be mounted if:
468 	 * It has the same mountpoint as a mounted filesystem, and
469 	 * It has the same type as that same mounted filesystem, and
470 	 * It has the same device name as that same mounted filesystem, OR
471 	 *     It is a nonremountable filesystem
472 	 */
473 	for (i = mntsize - 1; i >= 0; --i)
474 		if (strcmp(realfsfile, mntbuf[i].f_mntonname) == 0 &&
475 		    strcmp(fs->fs_vfstype, mntbuf[i].f_fstypename) == 0 &&
476 		    (!isremountable(fs->fs_vfstype) ||
477 		     (strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0)))
478 			return (1);
479 	return (0);
480 }
481 
482 int
483 isremountable(const char *vfsname)
484 {
485 	const char **cp;
486 
487 	for (cp = remountable_fs_names; *cp; cp++)
488 		if (strcmp(*cp, vfsname) == 0)
489 			return (1);
490 	return (0);
491 }
492 
493 int
494 allow_file_mount(const char *vfsname)
495 {
496 
497 	if (strcmp(vfsname, "nullfs") == 0)
498 		return (1);
499 	return (0);
500 }
501 
502 int
503 hasopt(const char *mntopts, const char *option)
504 {
505 	int negative, found;
506 	char *opt, *optbuf;
507 
508 	if (option[0] == 'n' && option[1] == 'o') {
509 		negative = 1;
510 		option += 2;
511 	} else
512 		negative = 0;
513 	optbuf = strdup(mntopts);
514 	found = 0;
515 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
516 		if (opt[0] == 'n' && opt[1] == 'o') {
517 			if (!strcasecmp(opt + 2, option))
518 				found = negative;
519 		} else if (!strcasecmp(opt, option))
520 			found = !negative;
521 	}
522 	free(optbuf);
523 	return (found);
524 }
525 
526 static void
527 append_arg(struct cpa *sa, char *arg)
528 {
529 	if (sa->c + 1 == sa->sz) {
530 		sa->sz = sa->sz == 0 ? 8 : sa->sz * 2;
531 		sa->a = realloc(sa->a, sizeof(*sa->a) * sa->sz);
532 		if (sa->a == NULL)
533 			xo_errx(1, "realloc failed");
534 	}
535 	sa->a[++sa->c] = arg;
536 }
537 
538 int
539 mountfs(const char *vfstype, const char *spec, const char *name, int flags,
540 	const char *options, const char *mntopts)
541 {
542 	struct statfs sf;
543 	int i, ret;
544 	char *optbuf, execname[PATH_MAX], mntpath[PATH_MAX];
545 	static struct cpa mnt_argv;
546 
547 	/* resolve the mountpoint with realpath(3) */
548 	if (allow_file_mount(vfstype)) {
549 		if (checkpath_allow_file(name, mntpath) != 0) {
550 			xo_warn("%s", mntpath);
551 			return (1);
552 		}
553 	} else {
554 		if (checkpath(name, mntpath) != 0) {
555 			xo_warn("%s", mntpath);
556 			return (1);
557 		}
558 	}
559 	name = mntpath;
560 
561 	if (mntopts == NULL)
562 		mntopts = "";
563 	optbuf = catopt(strdup(mntopts), options);
564 
565 	if (strcmp(name, "/") == 0)
566 		flags |= MNT_UPDATE;
567 	if (flags & MNT_FORCE)
568 		optbuf = catopt(optbuf, "force");
569 	if (flags & MNT_RDONLY)
570 		optbuf = catopt(optbuf, "ro");
571 	/*
572 	 * XXX
573 	 * The mount_mfs (newfs) command uses -o to select the
574 	 * optimization mode.  We don't pass the default "-o rw"
575 	 * for that reason.
576 	 */
577 	if (flags & MNT_UPDATE)
578 		optbuf = catopt(optbuf, "update");
579 
580 	/* Compatibility glue. */
581 	if (strcmp(vfstype, "msdos") == 0)
582 		vfstype = "msdosfs";
583 
584 	/* Construct the name of the appropriate mount command */
585 	(void)snprintf(execname, sizeof(execname), "mount_%s", vfstype);
586 
587 	mnt_argv.c = -1;
588 	append_arg(&mnt_argv, execname);
589 	mangle(optbuf, &mnt_argv);
590 	if (mountprog != NULL)
591 		strlcpy(execname, mountprog, sizeof(execname));
592 
593 	append_arg(&mnt_argv, strdup(spec));
594 	append_arg(&mnt_argv, strdup(name));
595 	append_arg(&mnt_argv, NULL);
596 
597 	if (debug) {
598 		if (use_mountprog(vfstype))
599 			xo_emit("{Lwc:exec}{:execname/%s}", execname);
600 		else
601 			xo_emit("{:execname/mount}{P: }{l:opts/-t}{P: }{l:opts/%s}", vfstype);
602 		for (i = 1; i < mnt_argv.c; i++)
603 			xo_emit("{P: }{l:opts}", mnt_argv.a[i]);
604 		xo_emit("\n");
605 		free(optbuf);
606 		free(mountprog);
607 		mountprog = NULL;
608 		return (0);
609 	}
610 
611 	if (use_mountprog(vfstype)) {
612 		ret = exec_mountprog(name, execname, mnt_argv.a);
613 	} else {
614 		ret = mount_fs(vfstype, mnt_argv.c, mnt_argv.a);
615 	}
616 
617 	free(optbuf);
618 	free(mountprog);
619 	mountprog = NULL;
620 
621 	if (verbose) {
622 		if (statfs(name, &sf) < 0) {
623 			xo_warn("statfs %s", name);
624 			return (1);
625 		}
626 		if (fstab_style) {
627 			xo_open_list("fstab");
628 			xo_open_instance("fstab");
629 			putfsent(&sf);
630 			xo_close_instance("fstab");
631 			xo_close_list("fstab");
632 		} else {
633 			xo_open_list("mounted");
634 			xo_open_instance("mounted");
635 			prmount(&sf);
636 			xo_close_instance("mounted");
637 			xo_close_list("mounted");
638 		}
639 	}
640 
641 	return (ret);
642 }
643 
644 void
645 prmount(struct statfs *sfp)
646 {
647 	uint64_t flags;
648 	unsigned int i;
649 	struct mntoptnames *o;
650 	struct passwd *pw;
651 	char *fsidbuf;
652 
653 	xo_emit("{:special/%hs}{L: on }{:node/%hs}{L: (}{:fstype}", sfp->f_mntfromname,
654 	    sfp->f_mntonname, sfp->f_fstypename);
655 
656 	flags = sfp->f_flags & MNT_VISFLAGMASK;
657 	for (o = optnames; flags != 0 && o->o_opt != 0; o++)
658 		if (flags & o->o_opt) {
659 			xo_emit("{D:, }{l:opts}", o->o_name);
660 			flags &= ~o->o_opt;
661 		}
662 	/*
663 	 * Inform when file system is mounted by an unprivileged user
664 	 * or privileged non-root user.
665 	 */
666 	if ((flags & MNT_USER) != 0 || sfp->f_owner != 0) {
667 		xo_emit("{D:, }{L:mounted by }");
668 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
669 			xo_emit("{:mounter/%hs}", pw->pw_name);
670 		else
671 			xo_emit("{:mounter/%hs}", sfp->f_owner);
672 	}
673 	if (verbose) {
674 		if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0) {
675 			xo_open_container("writes");
676 			xo_emit("{D:, }{Lwc:writes}{Lw:sync}{w:sync/%ju}{Lw:async}{:async/%ju}",
677 			    (uintmax_t)sfp->f_syncwrites,
678 			    (uintmax_t)sfp->f_asyncwrites);
679 			xo_close_container("writes");
680 		}
681 		if (sfp->f_syncreads != 0 || sfp->f_asyncreads != 0) {
682 			xo_open_container("reads");
683 			xo_emit("{D:, }{Lwc:reads}{Lw:sync}{w:sync/%ju}{Lw:async}{:async/%ju}",
684 			    (uintmax_t)sfp->f_syncreads,
685 			    (uintmax_t)sfp->f_asyncreads);
686 			xo_close_container("reads");
687 		}
688 		if (sfp->f_fsid.val[0] != 0 || sfp->f_fsid.val[1] != 0) {
689 			fsidbuf = malloc(sizeof(sfp->f_fsid) * 2 + 1);
690 			if (fsidbuf == NULL)
691 				xo_errx(1, "malloc failed");
692 			for (i = 0; i < sizeof(sfp->f_fsid); i++)
693 				sprintf(&fsidbuf[i * 2], "%02x",
694 				    ((u_char *)&sfp->f_fsid)[i]);
695 			fsidbuf[i * 2] = '\0';
696 			xo_emit("{D:, }{Lw:fsid}{:fsid}", fsidbuf);
697 			free(fsidbuf);
698 		}
699 		if (sfp->f_nvnodelistsize != 0) {
700 			xo_open_container("vnodes");
701 			xo_emit("{D:, }{Lwc:vnodes}{Lw:count}{w:count/%ju}",
702 			    (uintmax_t)sfp->f_nvnodelistsize);
703 			xo_close_container("vnodes");
704 		}
705 	}
706 	xo_emit("{D:)}\n");
707 }
708 
709 char *
710 catopt(char *s0, const char *s1)
711 {
712 	char *cp;
713 
714 	if (s1 == NULL || *s1 == '\0')
715 		return (s0);
716 
717 	if (s0 && *s0) {
718 		if (asprintf(&cp, "%s,%s", s0, s1) == -1)
719 			xo_errx(1, "asprintf failed");
720 	} else
721 		cp = strdup(s1);
722 
723 	if (s0)
724 		free(s0);
725 	return (cp);
726 }
727 
728 void
729 mangle(char *options, struct cpa *a)
730 {
731 	char *p, *s, *val;
732 
733 	for (s = options; (p = strsep(&s, ",")) != NULL;)
734 		if (*p != '\0') {
735 			if (strcmp(p, "noauto") == 0) {
736 				/*
737 				 * Do not pass noauto option to nmount().
738 				 * or external mount program.  noauto is
739 				 * only used to prevent mounting a filesystem
740 				 * when 'mount -a' is specified, and is
741 				 * not a real mount option.
742 				 */
743 				continue;
744 			} else if (strcmp(p, "late") == 0) {
745 				/*
746 				 * "late" is used to prevent certain file
747 				 * systems from being mounted before late
748 				 * in the boot cycle; for instance,
749 				 * loopback NFS mounts can't be mounted
750 				 * before mountd starts.
751 				 */
752 				continue;
753 			} else if (strcmp(p, "failok") == 0) {
754 				/*
755 				 * "failok" is used to prevent certain file
756 				 * systems from being causing the system to
757 				 * drop into single user mode in the boot
758 				 * cycle, and is not a real mount option.
759 				 */
760 				continue;
761 			} else if (strncmp(p, "mountprog", 9) == 0) {
762 				/*
763 				 * "mountprog" is used to force the use of
764 				 * userland mount programs.
765 				 */
766 				val = strchr(p, '=');
767                         	if (val != NULL) {
768                                 	++val;
769 					if (*val != '\0')
770 						mountprog = strdup(val);
771 				}
772 
773 				if (mountprog == NULL) {
774 					xo_errx(1, "Need value for -o mountprog");
775 				}
776 				continue;
777 			} else if (strcmp(p, "userquota") == 0) {
778 				continue;
779 			} else if (strncmp(p, userquotaeq,
780 			    sizeof(userquotaeq) - 1) == 0) {
781 				continue;
782 			} else if (strcmp(p, "groupquota") == 0) {
783 				continue;
784 			} else if (strncmp(p, groupquotaeq,
785 			    sizeof(groupquotaeq) - 1) == 0) {
786 				continue;
787 			} else if (*p == '-') {
788 				append_arg(a, p);
789 				p = strchr(p, '=');
790 				if (p != NULL) {
791 					*p = '\0';
792 					append_arg(a, p + 1);
793 				}
794 			} else {
795 				append_arg(a, strdup("-o"));
796 				append_arg(a, p);
797 			}
798 		}
799 }
800 
801 
802 char *
803 update_options(char *opts, char *fstab, int curflags)
804 {
805 	char *o, *p;
806 	char *cur;
807 	char *expopt, *newopt, *tmpopt;
808 
809 	if (opts == NULL)
810 		return (strdup(""));
811 
812 	/* remove meta options from list */
813 	remopt(fstab, MOUNT_META_OPTION_FSTAB);
814 	remopt(fstab, MOUNT_META_OPTION_CURRENT);
815 	cur = flags2opts(curflags);
816 
817 	/*
818 	 * Expand all meta-options passed to us first.
819 	 */
820 	expopt = NULL;
821 	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
822 		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
823 			expopt = catopt(expopt, fstab);
824 		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
825 			expopt = catopt(expopt, cur);
826 		else
827 			expopt = catopt(expopt, o);
828 	}
829 	free(cur);
830 	free(opts);
831 
832 	/*
833 	 * Remove previous contradictory arguments. Given option "foo" we
834 	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
835 	 * and "foo" - so we can deal with possible options like "notice".
836 	 */
837 	newopt = NULL;
838 	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
839 		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
840 			xo_errx(1, "malloc failed");
841 
842 		strcpy(tmpopt, "no");
843 		strcat(tmpopt, o);
844 		remopt(newopt, tmpopt);
845 		free(tmpopt);
846 
847 		if (strncmp("no", o, 2) == 0)
848 			remopt(newopt, o+2);
849 
850 		newopt = catopt(newopt, o);
851 	}
852 	free(expopt);
853 
854 	return (newopt);
855 }
856 
857 void
858 remopt(char *string, const char *opt)
859 {
860 	char *o, *p, *r;
861 
862 	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
863 		return;
864 
865 	r = string;
866 
867 	for (p = string; (o = strsep(&p, ",")) != NULL;) {
868 		if (strcmp(opt, o) != 0) {
869 			if (*r == ',' && *o != '\0')
870 				r++;
871 			while ((*r++ = *o++) != '\0')
872 			    ;
873 			*--r = ',';
874 		}
875 	}
876 	*r = '\0';
877 }
878 
879 void
880 usage(void)
881 {
882 
883 	xo_error("%s\n%s\n%s\n",
884 "usage: mount [-adflpruvw] [-F fstab] [-o options] [-t ufs | external_type]",
885 "       mount [-dfpruvw] special | node",
886 "       mount [-dfpruvw] [-o options] [-t ufs | external_type] special node");
887 	EXIT(1);
888 }
889 
890 void
891 putfsent(struct statfs *ent)
892 {
893 	struct fstab *fst;
894 	char *opts, *rw;
895 	int l;
896 
897 	opts = NULL;
898 	/* flags2opts() doesn't return the "rw" option. */
899 	if ((ent->f_flags & MNT_RDONLY) != 0)
900 		rw = NULL;
901 	else
902 		rw = catopt(NULL, "rw");
903 
904 	opts = flags2opts(ent->f_flags);
905 	opts = catopt(rw, opts);
906 
907 	if (strncmp(ent->f_mntfromname, "<below>", 7) == 0 ||
908 	    strncmp(ent->f_mntfromname, "<above>", 7) == 0) {
909 		strlcpy(ent->f_mntfromname,
910 		    (strnstr(ent->f_mntfromname, ":", 8) +1),
911 		    sizeof(ent->f_mntfromname));
912 	}
913 
914 	l = strlen(ent->f_mntfromname);
915 	xo_emit("{:device}{P:/%s}{P:/%s}{P:/%s}",
916 	    ent->f_mntfromname,
917 	    l < 8 ? "\t" : "",
918 	    l < 16 ? "\t" : "",
919 	    l < 24 ? "\t" : " ");
920 	l = strlen(ent->f_mntonname);
921 	xo_emit("{:mntpoint}{P:/%s}{P:/%s}{P:/%s}",
922 	    ent->f_mntonname,
923 	    l < 8 ? "\t" : "",
924 	    l < 16 ? "\t" : "",
925 	    l < 24 ? "\t" : " ");
926 	xo_emit("{:fstype}{P:\t}", ent->f_fstypename);
927 	l = strlen(opts);
928 	xo_emit("{:opts}{P:/%s}", opts,
929 	    l < 8 ? "\t" : " ");
930 	free(opts);
931 
932 	if ((fst = getfsspec(ent->f_mntfromname)))
933 		xo_emit("{P:\t}{n:dump/%u}{P: }{n:pass/%u}\n",
934 		    fst->fs_freq, fst->fs_passno);
935 	else if ((fst = getfsfile(ent->f_mntonname)))
936 		xo_emit("{P:\t}{n:dump/%u}{P: }{n:pass/%u}\n",
937 		    fst->fs_freq, fst->fs_passno);
938 	else if (strcmp(ent->f_fstypename, "ufs") == 0) {
939 		if (strcmp(ent->f_mntonname, "/") == 0)
940 			xo_emit("{P:\t}{n:dump/1}{P: }{n:pass/1}\n");
941 		else
942 			xo_emit("{P:\t}{n:dump/2}{P: }{n:pass/2}\n");
943 	} else
944 		xo_emit("{P:\t}{n:dump/0}{P: }{n:pass/0}\n");
945 }
946 
947 
948 char *
949 flags2opts(int flags)
950 {
951 	char *res;
952 
953 	res = NULL;
954 
955 	if (flags & MNT_RDONLY)		res = catopt(res, "ro");
956 	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
957 	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
958 	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
959 	if (flags & MNT_UNION)		res = catopt(res, "union");
960 	if (flags & MNT_ASYNC)		res = catopt(res, "async");
961 	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
962 	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
963 	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
964 	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
965 	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
966 	if (flags & MNT_MULTILABEL)	res = catopt(res, "multilabel");
967 	if (flags & MNT_ACLS)		res = catopt(res, "acls");
968 	if (flags & MNT_NFS4ACLS)	res = catopt(res, "nfsv4acls");
969 	if (flags & MNT_UNTRUSTED)	res = catopt(res, "untrusted");
970 	if (flags & MNT_NOCOVER)	res = catopt(res, "nocover");
971 	if (flags & MNT_EMPTYDIR)	res = catopt(res, "emptydir");
972 
973 	return (res);
974 }
975