xref: /netbsd/sbin/mount/mount.c (revision c4a72b64)
1 /*	$NetBSD: mount.c,v 1.64 2002/09/23 03:39:41 enami Exp $	*/
2 
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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 __COPYRIGHT("@(#) Copyright (c) 1980, 1989, 1993, 1994\n\
39 	The Regents of the University of California.  All rights reserved.\n");
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)mount.c	8.25 (Berkeley) 5/8/95";
45 #else
46 __RCSID("$NetBSD: mount.c,v 1.64 2002/09/23 03:39:41 enami Exp $");
47 #endif
48 #endif /* not lint */
49 
50 #include <sys/param.h>
51 #include <sys/mount.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 #define MOUNTNAMES
65 #include <fcntl.h>
66 #include <sys/disklabel.h>
67 #include <sys/ioctl.h>
68 
69 #include "pathnames.h"
70 #include "vfslist.h"
71 
72 static int	debug, verbose;
73 
74 static void	catopt __P((char **, const char *));
75 static const char *
76 		getfslab __P((const char *str));
77 static struct statfs *
78 		getmntpt __P((const char *));
79 static int 	getmntargs __P((struct statfs *, char *, size_t));
80 static int	hasopt __P((const char *, const char *));
81 static void	mangle __P((char *, int *, const char ***, int *));
82 static int	mountfs __P((const char *, const char *, const char *,
83 		    int, const char *, const char *, int, char *, size_t));
84 static void	prmount __P((struct statfs *));
85 static void	usage __P((void));
86 
87 #ifndef NO_MOUNT_PROGS
88 void	checkname __P((int, char *[]));
89 #endif
90 int	main __P((int, char *[]));
91 
92 /* Map from mount otions to printable formats. */
93 static const struct opt {
94 	int o_opt;
95 	int o_silent;
96 	const char *o_name;
97 } optnames[] = {
98 	__MNT_FLAGS
99 };
100 
101 static char ffs_fstype[] = "ffs";
102 
103 int
104 main(argc, argv)
105 	int argc;
106 	char *argv[];
107 {
108 	const char *mntfromname, *mntonname, **vfslist, *vfstype;
109 	struct fstab *fs;
110 	struct statfs *mntbuf;
111 	FILE *mountdfp;
112 	int all, ch, forceall, i, init_flags, mntsize, rval;
113 	char *options;
114 	const char *mountopts, *fstypename;
115 
116 #ifndef NO_MOUNT_PROGS
117 	/* if called as specific mount, call it's main mount routine */
118 	checkname(argc, argv);
119 #endif
120 
121 	/* started as "mount" */
122 	all = forceall = init_flags = 0;
123 	options = NULL;
124 	vfslist = NULL;
125 	vfstype = ffs_fstype;
126 	while ((ch = getopt(argc, argv, "Aadfo:rwt:uv")) != -1)
127 		switch (ch) {
128 		case 'A':
129 			all = forceall = 1;
130 			break;
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 				catopt(&options, optarg);
143 			break;
144 		case 'r':
145 			init_flags |= MNT_RDONLY;
146 			break;
147 		case 't':
148 			if (vfslist != NULL)
149 				errx(1,
150 				    "only one -t option may be specified.");
151 			vfslist = makevfslist(optarg);
152 			vfstype = optarg;
153 			break;
154 		case 'u':
155 			init_flags |= MNT_UPDATE;
156 			break;
157 		case 'v':
158 			verbose++;
159 			break;
160 		case 'w':
161 			init_flags &= ~MNT_RDONLY;
162 			break;
163 		case '?':
164 		default:
165 			usage();
166 			/* NOTREACHED */
167 		}
168 	argc -= optind;
169 	argv += optind;
170 
171 #define	BADTYPE(type)							\
172 	(strcmp(type, FSTAB_RO) &&					\
173 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
174 
175 	rval = 0;
176 	switch (argc) {
177 	case 0:
178 		if (all)
179 			while ((fs = getfsent()) != NULL) {
180 				if (BADTYPE(fs->fs_type))
181 					continue;
182 				if (checkvfsname(fs->fs_vfstype, vfslist))
183 					continue;
184 				if (hasopt(fs->fs_mntops, "noauto"))
185 					continue;
186 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
187 				    fs->fs_file, init_flags, options,
188 				    fs->fs_mntops, !forceall, NULL, 0))
189 					rval = 1;
190 			}
191 		else {
192 			if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
193 				err(1, "getmntinfo");
194 			for (i = 0; i < mntsize; i++) {
195 				if (checkvfsname(mntbuf[i].f_fstypename,
196 				    vfslist))
197 					continue;
198 				prmount(&mntbuf[i]);
199 			}
200 		}
201 		exit(rval);
202 		/* NOTREACHED */
203 	case 1:
204 		if (vfslist != NULL) {
205 			usage();
206 			/* NOTREACHED */
207 		}
208 
209 		if (init_flags & MNT_UPDATE) {
210 			if ((mntbuf = getmntpt(*argv)) == NULL)
211 				errx(1,
212 				    "unknown special file or file system %s.",
213 				    *argv);
214 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
215 				mntfromname = fs->fs_spec;
216 				/* ignore the fstab file options.  */
217 				fs->fs_mntops = NULL;
218 			} else
219 				mntfromname = mntbuf->f_mntfromname;
220 			mntonname  = mntbuf->f_mntonname;
221 			fstypename = mntbuf->f_fstypename;
222 			mountopts  = NULL;
223 		} else {
224 			if ((fs = getfsfile(*argv)) == NULL &&
225 			    (fs = getfsspec(*argv)) == NULL)
226 				errx(1,
227 				    "%s: unknown special file or file system.",
228 				    *argv);
229 			if (BADTYPE(fs->fs_type))
230 				errx(1, "%s has unknown file system type.",
231 				    *argv);
232 			mntfromname = fs->fs_spec;
233 			mntonname   = fs->fs_file;
234 			fstypename  = fs->fs_vfstype;
235 			mountopts   = fs->fs_mntops;
236 		}
237 		rval = mountfs(fstypename, mntfromname,
238 		    mntonname, init_flags, options, mountopts, 0, NULL, 0);
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) {
247 			if (strpbrk(argv[0], ":@") != NULL)
248 				vfstype = "nfs";
249 			else {
250 				vfstype = getfslab(argv[0]);
251 				if (vfstype == NULL)
252 					vfstype = ffs_fstype;
253 			}
254 		}
255 		rval = mountfs(vfstype,
256 		    argv[0], argv[1], init_flags, options, NULL, 0, NULL, 0);
257 		break;
258 	default:
259 		usage();
260 		/* NOTREACHED */
261 	}
262 
263 	/*
264 	 * If the mount was successfully, and done by root, tell mountd the
265 	 * good news.  Pid checks are probably unnecessary, but don't hurt.
266 	 */
267 	if (rval == 0 && getuid() == 0 &&
268 	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
269 		int pid;
270 
271 		if (fscanf(mountdfp, "%d", &pid) == 1 &&
272 		    pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
273 			err(1, "signal mountd");
274 		(void)fclose(mountdfp);
275 	}
276 
277 	exit(rval);
278 	/* NOTREACHED */
279 }
280 
281 int
282 hasopt(mntopts, option)
283 	const char *mntopts, *option;
284 {
285 	int negative, found;
286 	char *opt, *optbuf;
287 
288 	if (option[0] == 'n' && option[1] == 'o') {
289 		negative = 1;
290 		option += 2;
291 	} else
292 		negative = 0;
293 	optbuf = strdup(mntopts);
294 	found = 0;
295 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
296 		if (opt[0] == 'n' && opt[1] == 'o') {
297 			if (!strcasecmp(opt + 2, option))
298 				found = negative;
299 		} else if (!strcasecmp(opt, option))
300 			found = !negative;
301 	}
302 	free(optbuf);
303 	return (found);
304 }
305 
306 static int
307 mountfs(vfstype, spec, name, flags, options, mntopts, skipmounted, buf, buflen)
308 	const char *vfstype, *spec, *name, *options, *mntopts;
309 	int flags, skipmounted;
310 	char *buf;
311 	size_t buflen;
312 {
313 	/* List of directories containing mount_xxx subcommands. */
314 	static const char *edirs[] = {
315 #ifdef _PATH_RESCUE
316 		_PATH_RESCUE,
317 #endif
318 		_PATH_SBIN,
319 		_PATH_USRSBIN,
320 		NULL
321 	};
322 	const char **argv, **edir;
323 	struct statfs *sfp, sf;
324 	pid_t pid;
325 	int pfd[2];
326 	int argc, numfs, i, status, maxargc;
327 	char *optbuf, execname[MAXPATHLEN + 1], execbase[MAXPATHLEN],
328 	    mntpath[MAXPATHLEN];
329 
330 #ifdef __GNUC__
331 	(void) &name;
332 	(void) &optbuf;
333 	(void) &vfstype;
334 #endif
335 
336 	if (realpath(name, mntpath) == NULL) {
337 		warn("realpath %s", name);
338 		return (1);
339 	}
340 
341 	name = mntpath;
342 
343 	optbuf = NULL;
344 	if (mntopts)
345 		catopt(&optbuf, mntopts);
346 	if (options)
347 		catopt(&optbuf, options);
348 	if (!mntopts && !options)
349 		catopt(&optbuf, "rw");
350 
351 	if (!strcmp(name, "/"))
352 		flags |= MNT_UPDATE;
353 	else if (skipmounted) {
354 		if ((numfs = getmntinfo(&sfp, MNT_WAIT)) == 0) {
355 			warn("getmntinfo");
356 			return (1);
357 		}
358 		for(i = 0; i < numfs; i++) {
359 			/*
360 			 * XXX can't check f_mntfromname,
361 			 * thanks to mfs, union, etc.
362 			 */
363 			if (strncmp(name, sfp[i].f_mntonname, MNAMELEN) == 0 &&
364 			    strncmp(vfstype, sfp[i].f_fstypename,
365 				MFSNAMELEN) == 0) {
366 				if (verbose)
367 					(void)printf("%s on %s type %.*s: "
368 					    "%s\n",
369 					    sfp[i].f_mntfromname,
370 					    sfp[i].f_mntonname,
371 					    MFSNAMELEN,
372 					    sfp[i].f_fstypename,
373 					    "already mounted");
374 				return (0);
375 			}
376 		}
377 	}
378 	if (flags & MNT_FORCE)
379 		catopt(&optbuf, "force");
380 	if (flags & MNT_RDONLY)
381 		catopt(&optbuf, "ro");
382 
383 	if (flags & MNT_UPDATE) {
384 		catopt(&optbuf, "update");
385 		/* Figure out the fstype only if we defaulted to ffs */
386 		if (vfstype == ffs_fstype && statfs(name, &sf) != -1)
387 			vfstype = sf.f_fstypename;
388 	}
389 
390 	maxargc = 64;
391 	argv = malloc(sizeof(char *) * maxargc);
392 
393 	(void) snprintf(execbase, sizeof(execbase), "mount_%s", vfstype);
394 	argc = 0;
395 	argv[argc++] = execbase;
396 	if (optbuf)
397 		mangle(optbuf, &argc, &argv, &maxargc);
398 	argv[argc++] = spec;
399 	argv[argc++] = name;
400 	argv[argc] = NULL;
401 
402 	if (verbose && buf == NULL) {
403 		(void)printf("exec:");
404 		for (i = 0; i < argc; i++)
405 			(void)printf(" %s", argv[i]);
406 		(void)printf("\n");
407 	}
408 
409 	if (buf) {
410 		if (pipe(pfd) == -1)
411 			warn("Cannot create pipe");
412 	}
413 
414 	switch (pid = vfork()) {
415 	case -1:				/* Error. */
416 		warn("vfork");
417 		if (optbuf)
418 			free(optbuf);
419 		return (1);
420 
421 	case 0:					/* Child. */
422 		if (debug)
423 			_exit(0);
424 
425 		if (buf) {
426 			(void)close(pfd[0]);
427 			(void)close(STDOUT_FILENO);
428 			if (dup2(pfd[1], STDOUT_FILENO) == -1)
429 				warn("Cannot open fd to mount program");
430 		}
431 
432 		/* Go find an executable. */
433 		edir = edirs;
434 		do {
435 			(void)snprintf(execname,
436 			    sizeof(execname), "%s/%s", *edir, execbase);
437 			(void)execv(execname, (char * const *)argv);
438 			if (errno != ENOENT)
439 				warn("exec %s for %s", execname, name);
440 		} while (*++edir != NULL);
441 
442 		if (errno == ENOENT)
443 			warnx("%s not found for %s", execbase, name);
444 		_exit(1);
445 		/* NOTREACHED */
446 
447 	default:				/* Parent. */
448 		if (optbuf)
449 			free(optbuf);
450 
451 		if (buf || (options != NULL &&
452 		    strstr(options, "getargs") != NULL)) {
453 			char tbuf[1024], *ptr;
454 			int nread;
455 
456 			if (buf == NULL) {
457 				ptr = tbuf;
458 				buflen = sizeof(tbuf) - 1;
459 			} else {
460 				ptr = buf;
461 				buflen--;
462 			}
463 			(void)close(pfd[1]);
464 			(void)signal(SIGPIPE, SIG_IGN);
465 			while ((nread = read(pfd[0], ptr, buflen)) > 0) {
466 				buflen -= nread;
467 				ptr += nread;
468 			}
469 			*ptr = '\0';
470 			if (buflen == 0) {
471 				while (read(pfd[0], &nread, sizeof(nread)) > 0)
472 					continue;
473 			}
474 			if (buf == NULL)
475 				(void)fprintf(stdout, "%s", tbuf);
476 		}
477 
478 		if (waitpid(pid, &status, 0) < 0) {
479 			warn("waitpid");
480 			return (1);
481 		}
482 
483 		if (WIFEXITED(status)) {
484 			if (WEXITSTATUS(status) != 0)
485 				return (WEXITSTATUS(status));
486 		} else if (WIFSIGNALED(status)) {
487 			warnx("%s: %s", name, strsignal(WTERMSIG(status)));
488 			return (1);
489 		}
490 
491 		if (buf == NULL) {
492 			if (verbose) {
493 				if (statfs(name, &sf) < 0) {
494 					warn("statfs %s", name);
495 					return (1);
496 				}
497 				prmount(&sf);
498 			}
499 		}
500 		break;
501 	}
502 
503 	return (0);
504 }
505 
506 static void
507 prmount(sfp)
508 	struct statfs *sfp;
509 {
510 	int flags;
511 	const struct opt *o;
512 	struct passwd *pw;
513 	int f;
514 
515 	(void)printf("%s on %s type %.*s", sfp->f_mntfromname,
516 	    sfp->f_mntonname, MFSNAMELEN, sfp->f_fstypename);
517 
518 	flags = sfp->f_flags & MNT_VISFLAGMASK;
519 	for (f = 0, o = optnames; flags && o <
520 	    &optnames[sizeof(optnames)/sizeof(optnames[0])]; o++)
521 		if (flags & o->o_opt) {
522 			if (!o->o_silent || verbose)
523 				(void)printf("%s%s", !f++ ? " (" : ", ",
524 				    o->o_name);
525 			flags &= ~o->o_opt;
526 		}
527 	if (flags)
528 		(void)printf("%sunknown flag%s %#x", !f++ ? " (" : ", ",
529 		    flags & (flags - 1) ? "s" : "", flags);
530 	if (sfp->f_owner) {
531 		(void)printf("%smounted by ", !f++ ? " (" : ", ");
532 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
533 			(void)printf("%s", pw->pw_name);
534 		else
535 			(void)printf("%d", sfp->f_owner);
536 	}
537 	if (verbose) {
538 		(void)printf("%swrites: sync %ld async %ld",
539 		    !f++ ? " (" : ", ", sfp->f_syncwrites, sfp->f_asyncwrites);
540 		if (verbose > 1) {
541 			char buf[2048];
542 
543 			if (getmntargs(sfp, buf, sizeof(buf)))
544 				printf(", [%s: %s]", sfp->f_fstypename, buf);
545 		}
546 		printf(")\n");
547 	} else
548 		(void)printf("%s", f ? ")\n" : "\n");
549 }
550 
551 static int
552 getmntargs(sfs, buf, buflen)
553 	struct statfs *sfs;
554 	char *buf;
555 	size_t buflen;
556 {
557 
558 	if (mountfs(sfs->f_fstypename, sfs->f_mntfromname, sfs->f_mntonname, 0,
559 	    "getargs", NULL, 0, buf, buflen))
560 		return (0);
561 	else {
562 		if (*buf == '\0')
563 			return (0);
564 		if ((buf = strchr(buf, '\n')) != NULL)
565 			*buf = '\0';
566 		return (1);
567 	}
568 }
569 
570 static struct statfs *
571 getmntpt(name)
572 	const char *name;
573 {
574 	struct statfs *mntbuf;
575 	int i, mntsize;
576 
577 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
578 	for (i = 0; i < mntsize; i++)
579 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
580 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
581 			return (&mntbuf[i]);
582 	return (NULL);
583 }
584 
585 static void
586 catopt(sp, o)
587 	char **sp;
588 	const char *o;
589 {
590 	char *s;
591 	size_t i, j;
592 
593 	s = *sp;
594 	if (s) {
595 		i = strlen(s);
596 		j = i + 1 + strlen(o) + 1;
597 		s = realloc(s, j);
598 		(void)snprintf(s + i, j, ",%s", o);
599 	} else
600 		s = strdup(o);
601 	*sp = s;
602 }
603 
604 static void
605 mangle(options, argcp, argvp, maxargcp)
606 	char *options;
607 	int *argcp, *maxargcp;
608 	const char ***argvp;
609 {
610 	char *p, *s;
611 	int argc, maxargc;
612 	const char **argv;
613 
614 	argc = *argcp;
615 	argv = *argvp;
616 	maxargc = *maxargcp;
617 
618 	for (s = options; (p = strsep(&s, ",")) != NULL;) {
619 		/* Always leave space for one more argument and the NULL. */
620 		if (argc >= maxargc - 4) {
621 			maxargc <<= 1;
622 			argv = realloc(argv, maxargc * sizeof(char *));
623 		}
624 		if (*p != '\0') {
625 			if (*p == '-') {
626 				argv[argc++] = p;
627 				p = strchr(p, '=');
628 				if (p) {
629 					*p = '\0';
630 					argv[argc++] = p+1;
631 				}
632 			} else if (strcmp(p, "rw") != 0) {
633 				argv[argc++] = "-o";
634 				argv[argc++] = p;
635 			}
636 		}
637 	}
638 
639 	*argcp = argc;
640 	*argvp = argv;
641 	*maxargcp = maxargc;
642 }
643 
644 /* Deduce the filesystem type from the disk label. */
645 static const char *
646 getfslab(str)
647 	const char *str;
648 {
649 	struct disklabel dl;
650 	int fd;
651 	int part;
652 	const char *vfstype;
653 	u_char fstype;
654 	char buf[MAXPATHLEN + 1];
655 	char *sp, *ep;
656 
657 	if ((fd = open(str, O_RDONLY)) == -1) {
658 		/*
659 		 * Iff we get EBUSY try the raw device. Since mount always uses
660 		 * the block device we know we are never passed a raw device.
661 		 */
662 		if (errno != EBUSY)
663 			err(1, "cannot open `%s'", str);
664 		strlcpy(buf, str, MAXPATHLEN);
665 		if ((sp = strrchr(buf, '/')) != NULL)
666 			++sp;
667 		else
668 			sp = buf;
669 		for (ep = sp + strlen(sp) + 1;  ep > sp; ep--)
670 			*ep = *(ep - 1);
671 		*sp = 'r';
672 
673 		/* Silently fail here - mount call can display error */
674 		if ((fd = open(buf, O_RDONLY)) == -1)
675 			return (NULL);
676 	}
677 
678 	if (ioctl(fd, DIOCGDINFO, &dl) == -1) {
679 		(void) close(fd);
680 		return (NULL);
681 	}
682 
683 	(void) close(fd);
684 
685 	part = str[strlen(str) - 1] - 'a';
686 
687 	if (part < 0 || part >= dl.d_npartitions)
688 		return (NULL);
689 
690 	/* Return NULL for unknown types - caller can fall back to ffs */
691 	if ((fstype = dl.d_partitions[part].p_fstype) >= FSMAXMOUNTNAMES)
692 		vfstype = NULL;
693 	else
694 		vfstype = mountnames[fstype];
695 
696 	return (vfstype);
697 }
698 
699 static void
700 usage()
701 {
702 
703 	(void)fprintf(stderr,
704 	    "usage: mount %s\n       mount %s\n       mount %s\n",
705 	    "[-Aadfruvw] [-t type]",
706 	    "[-dfruvw] special | node",
707 	    "[-dfruvw] [-o options] [-t type] special node");
708 	exit(1);
709 	/* NOTREACHED */
710 }
711