xref: /openbsd/sbin/umount/umount.c (revision 6f40fd34)
1 /*	$OpenBSD: umount.c,v 1.27 2016/12/16 17:44:59 krw Exp $	*/
2 /*	$NetBSD: umount.c,v 1.16 1996/05/11 14:13:55 mycroft Exp $	*/
3 
4 /*-
5  * Copyright (c) 1980, 1989, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/stat.h>
34 #include <sys/mount.h>
35 #include <sys/time.h>
36 #include <sys/socket.h>
37 #include <sys/socketvar.h>
38 
39 #include <netdb.h>
40 #include <rpc/rpc.h>
41 #include <rpc/pmap_clnt.h>
42 #include <rpc/pmap_prot.h>
43 #include <nfs/rpcv2.h>
44 
45 #include <err.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <limits.h>
51 #include <util.h>
52 
53 typedef enum { MNTON, MNTFROM } mntwhat;
54 
55 int	fflag, verbose;
56 char	**typelist = NULL;
57 char	*nfshost;
58 
59 char	*getmntname(char *, mntwhat, char *);
60 void	 maketypelist(char *);
61 int	 selected(const char *);
62 int	 namematch(struct hostent *);
63 int	 umountall(void);
64 int	 umountfs(char *);
65 void	 usage(void);
66 int	 xdr_dir(XDR *, char *);
67 
68 int
69 main(int argc, char *argv[])
70 {
71 	int all, ch, errs;
72 
73 	/* Start disks transferring immediately. */
74 	sync();
75 
76 	all = 0;
77 	while ((ch = getopt(argc, argv, "afh:t:v")) != -1)
78 		switch (ch) {
79 		case 'a':
80 			all = 1;
81 			break;
82 		case 'f':
83 			fflag = MNT_FORCE;
84 			break;
85 		case 'h':	/* -h implies -a. */
86 			all = 1;
87 			nfshost = optarg;
88 			break;
89 		case 't':
90 			if (typelist != NULL)
91 				errx(1, "only one -t option may be specified.");
92 			maketypelist(optarg);
93 			break;
94 		case 'v':
95 			verbose = 1;
96 			break;
97 		default:
98 			usage();
99 			/* NOTREACHED */
100 		}
101 	argc -= optind;
102 	argv += optind;
103 
104 	if ((argc == 0 && !all) || (argc != 0 && all))
105 		usage();
106 
107 	/* -h implies "-t nfs" if no -t flag. */
108 	if ((nfshost != NULL) && (typelist == NULL))
109 		maketypelist(MOUNT_NFS);
110 
111 	if (all)
112 		errs = umountall();
113 	else
114 		for (errs = 0; *argv != NULL; ++argv)
115 			if (umountfs(*argv) != 0)
116 				errs = 1;
117 	return (errs);
118 }
119 
120 int
121 umountall(void)
122 {
123 	struct statfs *fs;
124 	int n;
125 	int rval;
126 
127 	n = getmntinfo(&fs, MNT_NOWAIT);
128 	if (n == 0)
129 		err(1, NULL);
130 
131 	rval = 0;
132 	while (--n >= 0) {
133 		/* Ignore the root. */
134 		if (strncmp(fs[n].f_mntonname, "/", MNAMELEN) == 0)
135 			continue;
136 		if (!selected(fs[n].f_fstypename))
137 			continue;
138 		if (umountfs(fs[n].f_mntonname))
139 			rval = 1;
140 	}
141 	return (rval);
142 }
143 
144 int
145 umountfs(char *oname)
146 {
147 	struct hostent *hp;
148 #ifndef NO_NFS
149 	struct sockaddr_in saddr;
150 	struct timeval pertry, try;
151 	CLIENT *clp;
152 	int so;
153 #endif
154 	struct stat sb;
155 	char *delimp, *hostp, *mntpt;
156 	char *name, *newname, rname[PATH_MAX], type[MFSNAMELEN];
157 
158 	if (isduid(oname, 0) || realpath(oname, rname) == NULL)
159 		mntpt = name = oname;
160 	else
161 		mntpt = name = rname;
162 	newname = NULL;
163 
164 	/* If we can stat the file, check to see if it is a device or non-dir */
165 	if (stat(name, &sb) == 0) {
166 	    if (S_ISBLK(sb.st_mode)) {
167 		if ((mntpt = getmntname(name, MNTON, type)) == NULL) {
168 			warnx("%s: not currently mounted", name);
169 			return (1);
170 		}
171 	    } else if (!S_ISDIR(sb.st_mode)) {
172 		warnx("%s: not a directory or special device", name);
173 		return (1);
174 	    }
175 	}
176 
177 	/*
178 	 * Look up the name in the mount table.
179 	 * 99.9% of the time the path in the kernel is the one
180 	 * realpath() returns but check the original just in case...
181 	 */
182 	if (!(newname = getmntname(name, MNTFROM, type)) &&
183 	    !(mntpt = getmntname(name, MNTON, type)) ) {
184 		mntpt = oname;
185 		if (!(newname = getmntname(oname, MNTFROM, type)) &&
186 		    !(mntpt = getmntname(oname, MNTON, type))) {
187 			warnx("%s: not currently mounted", oname);
188 			return (1);
189 		}
190 	}
191 	if (newname)
192 		name = newname;
193 
194 	if (!selected(type))
195 		return (1);
196 
197 	if (!strncmp(type, MOUNT_NFS, MFSNAMELEN)) {
198 		if ((delimp = strchr(name, '@')) != NULL) {
199 			hostp = delimp + 1;
200 			*delimp = '\0';
201 			hp = gethostbyname(hostp);
202 			*delimp = '@';
203 		} else if ((delimp = strchr(name, ':')) != NULL) {
204 			*delimp = '\0';
205 			hostp = name;
206 			hp = gethostbyname(hostp);
207 			name = delimp + 1;
208 			*delimp = ':';
209 		} else
210 			hp = NULL;
211 		if (!namematch(hp))
212 			return (1);
213 	}
214 
215 	if (verbose)
216 		printf("%s: unmount from %s\n", name, mntpt);
217 
218 	if (unmount(mntpt, fflag) < 0) {
219 		warn("%s", mntpt);
220 		return (1);
221 	}
222 
223 #ifndef NO_NFS
224 	if (!strncmp(type, MOUNT_NFS, MFSNAMELEN) &&
225 	    (hp != NULL) && !(fflag & MNT_FORCE)) {
226 		enum clnt_stat clnt_stat;
227 
228 		*delimp = '\0';
229 		memset(&saddr, 0, sizeof(saddr));
230 		saddr.sin_family = AF_INET;
231 		saddr.sin_port = 0;
232 		memmove(&saddr.sin_addr, hp->h_addr, hp->h_length);
233 		pertry.tv_sec = 3;
234 		pertry.tv_usec = 0;
235 		so = RPC_ANYSOCK;
236 		if ((clp = clntudp_create(&saddr,
237 		    RPCPROG_MNT, RPCMNT_VER1, pertry, &so)) == NULL) {
238 			clnt_pcreateerror("Cannot MNT RPC");
239 			return (1);
240 		}
241 		clp->cl_auth = authunix_create_default();
242 		try.tv_sec = 20;
243 		try.tv_usec = 0;
244 		clnt_stat = clnt_call(clp,
245 		    RPCMNT_UMOUNT, xdr_dir, name, xdr_void, (caddr_t)0, try);
246 		if (clnt_stat != RPC_SUCCESS) {
247 			clnt_perror(clp, "Bad MNT RPC");
248 			return (1);
249 		}
250 		auth_destroy(clp->cl_auth);
251 		clnt_destroy(clp);
252 	}
253 #endif
254 	return (0);
255 }
256 
257 char *
258 getmntname(char *name, mntwhat what, char *type)
259 {
260 	struct statfs *mntbuf;
261 	int n;
262 
263 	if ((n = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0) {
264 		warn("getmntinfo");
265 		return (NULL);
266 	}
267 	while (--n >= 0) {
268 		if ((what == MNTON) &&
269 		    (strncmp(mntbuf[n].f_mntfromname, name, MNAMELEN) == 0 ||
270 		     strncmp(mntbuf[n].f_mntfromspec, name, MNAMELEN) == 0)) {
271 			if (type)
272 				memcpy(type, mntbuf[n].f_fstypename,
273 				    sizeof(mntbuf[n].f_fstypename));
274 			return (mntbuf[n].f_mntonname);
275 		}
276 		if ((what == MNTFROM) &&
277 		    (strncmp(mntbuf[n].f_mntonname, name, MNAMELEN) == 0)) {
278 			if (type)
279 				memcpy(type, mntbuf[n].f_fstypename,
280 				    sizeof(mntbuf[n].f_fstypename));
281 			return (mntbuf[n].f_mntfromname);
282 		}
283 	}
284 	return (NULL);
285 }
286 
287 static enum { IN_LIST, NOT_IN_LIST } which;
288 
289 int
290 selected(const char *type)
291 {
292 	char **av;
293 
294 	/* If no type specified, it's always selected. */
295 	if (typelist == NULL)
296 		return (1);
297 	for (av = typelist; *av != NULL; ++av)
298 		if (!strncmp(type, *av, MFSNAMELEN))
299 			return (which == IN_LIST ? 1 : 0);
300 	return (which == IN_LIST ? 0 : 1);
301 }
302 
303 void
304 maketypelist(char *fslist)
305 {
306 	int i;
307 	char *nextcp, **av;
308 
309 	if ((fslist == NULL) || (fslist[0] == '\0'))
310 		errx(1, "empty type list");
311 
312 	/*
313 	 * XXX
314 	 * Note: the syntax is "noxxx,yyy" for no xxx's and
315 	 * no yyy's, not the more intuitive "noxxx,noyyy".
316 	 */
317 	if (fslist[0] == 'n' && fslist[1] == 'o') {
318 		fslist += 2;
319 		which = NOT_IN_LIST;
320 	} else
321 		which = IN_LIST;
322 
323 	/* Count the number of types. */
324 	for (i = 1, nextcp = fslist; (nextcp = strchr(nextcp, ',')); i++)
325 		++nextcp;
326 
327 	/* Build an array of that many types. */
328 	if ((av = typelist = calloc(i + 1, sizeof(char *))) == NULL)
329 		err(1, NULL);
330 	av[0] = fslist;
331 	for (i = 1, nextcp = fslist; (nextcp = strchr(nextcp, ',')); i++) {
332 		*nextcp = '\0';
333 		av[i] = ++nextcp;
334 	}
335 	/* Terminate the array. */
336 	av[i] = NULL;
337 }
338 
339 int
340 namematch(struct hostent *hp)
341 {
342 	char *cp, **np;
343 
344 	if ((hp == NULL) || (nfshost == NULL))
345 		return (1);
346 
347 	if (strcasecmp(nfshost, hp->h_name) == 0)
348 		return (1);
349 
350 	if ((cp = strchr(hp->h_name, '.')) != NULL) {
351 		*cp = '\0';
352 		if (strcasecmp(nfshost, hp->h_name) == 0)
353 			return (1);
354 	}
355 	for (np = hp->h_aliases; *np; np++) {
356 		if (strcasecmp(nfshost, *np) == 0)
357 			return (1);
358 		if ((cp = strchr(*np, '.')) != NULL) {
359 			*cp = '\0';
360 			if (strcasecmp(nfshost, *np) == 0)
361 				return (1);
362 		}
363 	}
364 	return (0);
365 }
366 
367 #ifndef NO_NFS
368 /*
369  * xdr routines for mount rpc's
370  */
371 int
372 xdr_dir(XDR *xdrsp, char *dirp)
373 {
374 	return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
375 }
376 #endif
377 
378 void
379 usage(void)
380 {
381 	fprintf(stderr,
382 	    "usage: %s\n       %s\n",
383 	    "umount [-fv] special | node",
384 	    "umount -a [-fv] [-h host] [-t type]");
385 	exit(1);
386 }
387