1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29
30 /*
31 * University Copyright- Copyright (c) 1982, 1986, 1988
32 * The Regents of the University of California
33 * All Rights Reserved
34 *
35 * University Acknowledgment- Portions of this document are derived from
36 * software developed by the University of California, Berkeley, and its
37 * contributors.
38 */
39
40 #pragma ident "%Z%%M% %I% %E% SMI"
41
42 /*
43 * nfs umount
44 */
45
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <stdarg.h>
50 #include <signal.h>
51 #include <unistd.h>
52 #include <kstat.h>
53 #include <rpc/rpc.h>
54 #include <sys/mnttab.h>
55 #include <sys/mount.h>
56 #include <sys/mntent.h>
57 #include <nfs/nfs.h>
58 #include <nfs/nfs_clnt.h>
59 #include <rpcsvc/mount.h>
60 #include <errno.h>
61 #include <locale.h>
62 #include <fslib.h>
63 #include <priv.h>
64 #include <tsol/label.h>
65 #include "replica.h"
66
67 #define RET_OK 0
68 #define RET_ERR 32
69
70 #ifdef __STDC__
71 static void pr_err(const char *fmt, ...);
72 #else
73 static void pr_err(char *fmt, va_dcl);
74 #endif
75 static void usage();
76 static int nfs_unmount(char *, int);
77 static void inform_server(char *, char *, bool_t);
78 static struct extmnttab *mnttab_find();
79 extern int __clnt_bindresvport(CLIENT *);
80
81 static int is_v4_mount(struct extmnttab *);
82
83 static char *myname;
84 static char typename[64];
85
86 int
main(int argc,char * argv[])87 main(int argc, char *argv[])
88 {
89 extern int optind;
90 int c;
91 int umnt_flag = 0;
92
93 (void) setlocale(LC_ALL, "");
94
95 #if !defined(TEXT_DOMAIN)
96 #define TEXT_DOMAIN "SYS_TEST"
97 #endif
98 (void) textdomain(TEXT_DOMAIN);
99
100 myname = strrchr(argv[0], '/');
101 myname = myname ? myname+1 : argv[0];
102 (void) snprintf(typename, sizeof (typename), "nfs %s", myname);
103 argv[0] = typename;
104
105 /*
106 * Set options
107 */
108 while ((c = getopt(argc, argv, "f")) != EOF) {
109 switch (c) {
110 case 'f':
111 umnt_flag |= MS_FORCE; /* forced unmount is desired */
112 break;
113 default:
114 usage();
115 exit(RET_ERR);
116 }
117 }
118 if (argc - optind != 1) {
119 usage();
120 exit(RET_ERR);
121 }
122
123 if (!priv_ineffect(PRIV_SYS_MOUNT) ||
124 !priv_ineffect(PRIV_NET_PRIVADDR)) {
125 pr_err(gettext("insufficient privileges\n"));
126 exit(RET_ERR);
127 }
128
129 /*
130 * On a labeled system, a MAC flag may be needed if the mount is
131 * read-down, so attempt to assert it but ignore errors in any case.
132 */
133 if (is_system_labeled())
134 (void) setpflags(NET_MAC_AWARE, 1);
135
136 /*
137 * exit, really
138 */
139 return (nfs_unmount(argv[optind], umnt_flag));
140 }
141
142 static void
pr_err(const char * fmt,...)143 pr_err(const char *fmt, ...)
144 {
145 va_list ap;
146
147 va_start(ap, fmt);
148 (void) fprintf(stderr, "%s: ", typename);
149 (void) vfprintf(stderr, fmt, ap);
150 (void) fflush(stderr);
151 va_end(ap);
152 }
153
154 static void
usage()155 usage()
156 {
157 (void) fprintf(stderr,
158 gettext("Usage: nfs umount [-f] {server:path | dir}\n"));
159 exit(RET_ERR);
160 }
161
162 static int
nfs_unmount(char * pathname,int umnt_flag)163 nfs_unmount(char *pathname, int umnt_flag)
164 {
165 struct extmnttab *mntp;
166 bool_t quick = FALSE;
167 int is_v4 = FALSE;
168
169 mntp = mnttab_find(pathname);
170 if (mntp) {
171 pathname = mntp->mnt_mountp;
172 }
173
174 if (mntp)
175 is_v4 = is_v4_mount(mntp);
176
177 /* Forced unmount will almost always be successful */
178 if (umount2(pathname, umnt_flag) < 0) {
179 if (errno == EBUSY) {
180 pr_err(gettext("%s: is busy\n"), pathname);
181 } else {
182 pr_err(gettext("%s: not mounted\n"), pathname);
183 }
184 return (RET_ERR);
185 }
186
187 /* All done if it's v4 */
188 if (is_v4 == TRUE)
189 return (RET_OK);
190
191 /* Inform server quickly in case of forced unmount */
192 if (umnt_flag & MS_FORCE)
193 quick = TRUE;
194
195 if (mntp) {
196 inform_server(mntp->mnt_special, mntp->mnt_mntopts, quick);
197 }
198
199 return (RET_OK);
200 }
201
202 /*
203 * Find the mnttab entry that corresponds to "name".
204 * We're not sure what the name represents: either
205 * a mountpoint name, or a special name (server:/path).
206 * Return the last entry in the file that matches.
207 */
208 static struct extmnttab *
mnttab_find(dirname)209 mnttab_find(dirname)
210 char *dirname;
211 {
212 FILE *fp;
213 struct extmnttab mnt;
214 struct extmnttab *res = NULL;
215
216 fp = fopen(MNTTAB, "r");
217 if (fp == NULL) {
218 pr_err("%s: %s\n", MNTTAB, strerror(errno));
219 return (NULL);
220 }
221 while (getextmntent(fp, &mnt, sizeof (struct extmnttab)) == 0) {
222 if (strcmp(mnt.mnt_mountp, dirname) == 0 ||
223 strcmp(mnt.mnt_special, dirname) == 0) {
224 if (res)
225 fsfreemnttab(res);
226 res = fsdupmnttab(&mnt);
227 }
228 }
229
230 (void) fclose(fp);
231 return (res);
232 }
233
234 /*
235 * If quick is TRUE, it will try to inform server quickly
236 * as possible.
237 */
238 static void
inform_server(char * string,char * opts,bool_t quick)239 inform_server(char *string, char *opts, bool_t quick)
240 {
241 struct timeval timeout;
242 CLIENT *cl;
243 enum clnt_stat rpc_stat;
244 struct replica *list;
245 int i, n;
246 char *p = NULL;
247 static struct timeval create_timeout = {5, 0};
248 static struct timeval *timep;
249
250 list = parse_replica(string, &n);
251
252 if (list == NULL) {
253 if (n < 0)
254 pr_err(gettext("%s is not hostname:path format\n"),
255 string);
256 else
257 pr_err(gettext("no memory\n"));
258 return;
259 }
260
261 /*
262 * If mounted with -o public, then no need to contact server
263 * because mount protocol was not used.
264 */
265 if (opts != NULL)
266 p = strstr(opts, MNTOPT_PUBLIC);
267
268 if (p != NULL) {
269 i = strlen(MNTOPT_PUBLIC);
270 /*
271 * Now make sure the match of "public" isn't a substring
272 * of another option.
273 */
274 if (((p == opts) || (*(p-1) == ',')) &&
275 ((p[i] == ',') || (p[i] == '\0')))
276 return;
277 }
278
279 for (i = 0; i < n; i++) {
280 int vers;
281
282 /*
283 * Skip file systems mounted using WebNFS, because mount
284 * protocol was not used.
285 */
286 if (strcmp(list[i].host, "nfs") == 0 && strncmp(list[i].path,
287 "//", 2) == 0)
288 continue;
289
290 vers = MOUNTVERS;
291 retry:
292 /*
293 * Use 5 sec. timeout if file system is forced unmounted,
294 * otherwise use default timeout to create a client handle.
295 * This would minimize the time to force unmount a file
296 * system reside on a server that is down.
297 */
298 timep = (quick ? &create_timeout : NULL);
299 cl = clnt_create_timed(list[i].host, MOUNTPROG, vers,
300 "datagram_n", timep);
301 /*
302 * Do not print any error messages in case of forced
303 * unmount.
304 */
305 if (cl == NULL) {
306 if (!quick)
307 pr_err("%s:%s %s\n", list[i].host, list[i].path,
308 clnt_spcreateerror(
309 "server not responding"));
310 continue;
311 }
312 /*
313 * Now it is most likely that the NFS client will be able
314 * to contact the server since rpcbind is running on
315 * the server. There is still a small window in which
316 * server can be unreachable.
317 */
318
319 if (__clnt_bindresvport(cl) < 0) {
320 if (!quick)
321 pr_err(gettext(
322 "couldn't bind to reserved port\n"));
323 clnt_destroy(cl);
324 return;
325 }
326 if ((cl->cl_auth = authsys_create_default()) == NULL) {
327 if (!quick)
328 pr_err(gettext(
329 "couldn't create authsys structure\n"));
330 clnt_destroy(cl);
331 return;
332 }
333 timeout.tv_usec = 0;
334 timeout.tv_sec = 5;
335 clnt_control(cl, CLSET_RETRY_TIMEOUT, (char *)&timeout);
336 timeout.tv_sec = 25;
337 rpc_stat = clnt_call(cl, MOUNTPROC_UMNT, xdr_dirpath,
338 (char *)&list[i].path, xdr_void, (char *)NULL,
339 timeout);
340 AUTH_DESTROY(cl->cl_auth);
341 clnt_destroy(cl);
342 if (rpc_stat == RPC_PROGVERSMISMATCH && vers == MOUNTVERS) {
343 /*
344 * The rare case of a v3-only server
345 */
346 vers = MOUNTVERS3;
347 goto retry;
348 }
349 if (rpc_stat != RPC_SUCCESS)
350 pr_err("%s\n", clnt_sperror(cl, "unmount"));
351 }
352
353 free_replica(list, n);
354 }
355
356 /*
357 * This function's behavior is taken from nfsstat.
358 * Trying to determine what NFS version was used for the mount.
359 */
360 int
is_v4_mount(struct extmnttab * mntp)361 is_v4_mount(struct extmnttab *mntp)
362 {
363 kstat_ctl_t *kc = NULL; /* libkstat cookie */
364 kstat_t *ksp;
365 struct mntinfo_kstat mik;
366
367 if (mntp == NULL)
368 return (FALSE);
369
370 if ((kc = kstat_open()) == NULL)
371 return (FALSE);
372
373 for (ksp = kc->kc_chain; ksp; ksp = ksp->ks_next) {
374 if (ksp->ks_type != KSTAT_TYPE_RAW)
375 continue;
376 if (strcmp(ksp->ks_module, "nfs") != 0)
377 continue;
378 if (strcmp(ksp->ks_name, "mntinfo") != 0)
379 continue;
380 if (mntp->mnt_minor != ksp->ks_instance)
381 continue;
382
383 if (kstat_read(kc, ksp, &mik) == -1)
384 continue;
385
386 if (mik.mik_vers == 4)
387 return (TRUE);
388 else
389 return (FALSE);
390 }
391 return (FALSE);
392 }
393