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