1 /* $NetBSD: checkmount_default.c,v 1.1.1.3 2015/01/17 16:34:16 christos Exp $ */
2
3 /*
4 * Copyright (c) 1997-2014 Erez Zadok
5 * Copyright (c) 1990 Jan-Simon Pendry
6 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
7 * Copyright (c) 1990 The Regents of the University of California.
8 * All rights reserved.
9 *
10 * This code is derived from software contributed to Berkeley by
11 * Jan-Simon Pendry at Imperial College, London.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 *
38 * File: am-utils/conf/checkmount/checkmount_default.c
39 *
40 */
41
42 #ifdef HAVE_CONFIG_H
43 # include <config.h>
44 #endif /* HAVE_CONFIG_H */
45 #include <am_defs.h>
46
47 #ifndef _PATH_MTAB
48 #define _PATH_MTAB "/etc/mtab"
49 #endif /* not _PATH_MTAB */
50
51 extern int is_same_host(char *name1, char *name2, struct in_addr addr2);
52
53
54 int
fixmount_check_mount(char * host,struct in_addr hostaddr,char * path)55 fixmount_check_mount(char *host, struct in_addr hostaddr, char *path)
56 {
57 FILE *mtab;
58 mntent_t *ment;
59 int found = 0;
60
61 /* scan mtab for path */
62 if (!(mtab = setmntent(_PATH_MTAB, "r"))) {
63 perror(_PATH_MTAB);
64 exit(1);
65 }
66
67 /*
68 * setmntent() doesn't do locking in read-only mode. Too bad -- it seems to
69 * rely on mount() and friends to do atomic updates by renaming the file.
70 * Well, our patched amd rewrites mtab in place to avoid NFS lossage, so
71 * better do the locking ourselves.
72 */
73 #ifdef HAVE_FLOCK
74 if (flock(fileno(mtab), LOCK_SH) < 0) {
75 #else /* not HAVE_FLOCK */
76 if (lockf(fileno(mtab), F_LOCK, 0) < 0) {
77 #endif /* not HAVE_FLOCK */
78 perror(_PATH_MTAB);
79 exit(1);
80 }
81
82 while (!found && (ment = getmntent(mtab))) {
83 char *colon;
84
85 if ((colon = strchr(ment->mnt_fsname, ':'))) {
86 *colon = '\0';
87 if ((STREQ(colon + 1, path) ||
88 STREQ(ment->mnt_dir, path)) &&
89 is_same_host(ment->mnt_fsname, host, hostaddr))
90 found = 1;
91 }
92 }
93
94 (void) endmntent(mtab);
95
96 if (!found) {
97 char *swap;
98
99 /* swap files never show up in mtab, only root fs */
100 if ((swap = strstr(path, "swap"))) {
101 strncpy(swap, "root", 4); /* this should NOT use xstrlcpy */
102 found = fixmount_check_mount(host, hostaddr, path);
103 strncpy(swap, "swap", 4); /* this should NOT use xstrlcpy */
104 }
105 }
106 return found;
107 }
108