1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1980, 1988, 1993
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __SCCSID("@(#)fstab.c 8.1 (Berkeley) 6/4/93");
34 __FBSDID("$FreeBSD: stable/12/lib/libc/gen/fstab.c 335898 2018-07-03 17:31:45Z jhb $");
35
36 #include "namespace.h"
37 #include <sys/param.h>
38 #include <sys/mount.h>
39 #include <sys/stat.h>
40
41 #include <errno.h>
42 #include <fstab.h>
43 #include <paths.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 #include <vis.h>
49 #include "un-namespace.h"
50
51 static FILE *_fs_fp;
52 static struct fstab _fs_fstab;
53 static int LineNo = 0;
54 static char *path_fstab;
55 static char fstab_path[PATH_MAX];
56 static int fsp_set = 0;
57
58 static void error(int);
59 static void fixfsfile(void);
60 static int fstabscan(void);
61
62 void
setfstab(const char * file)63 setfstab(const char *file)
64 {
65
66 if (file == NULL) {
67 path_fstab = _PATH_FSTAB;
68 } else {
69 strncpy(fstab_path, file, PATH_MAX);
70 fstab_path[PATH_MAX - 1] = '\0';
71 path_fstab = fstab_path;
72 }
73 fsp_set = 1;
74
75 return;
76 }
77
78 const char *
getfstab(void)79 getfstab(void)
80 {
81
82 if (fsp_set)
83 return (path_fstab);
84 else
85 return (_PATH_FSTAB);
86 }
87
88 static void
fixfsfile(void)89 fixfsfile(void)
90 {
91 static char buf[sizeof(_PATH_DEV) + MNAMELEN];
92 struct stat sb;
93 struct statfs sf;
94
95 if (_fs_fstab.fs_file != NULL && strcmp(_fs_fstab.fs_file, "/") != 0)
96 return;
97 if (statfs("/", &sf) != 0)
98 return;
99 if (sf.f_mntfromname[0] == '/')
100 buf[0] = '\0';
101 else
102 strcpy(buf, _PATH_DEV);
103 strcat(buf, sf.f_mntfromname);
104 if (stat(buf, &sb) != 0 ||
105 (!S_ISBLK(sb.st_mode) && !S_ISCHR(sb.st_mode)))
106 return;
107 _fs_fstab.fs_spec = buf;
108 }
109
110 static int
fstabscan(void)111 fstabscan(void)
112 {
113 char *cp, *p;
114 #define MAXLINELENGTH 1024
115 static char line[MAXLINELENGTH];
116 char subline[MAXLINELENGTH];
117 int typexx;
118
119 for (;;) {
120
121 if (!(p = fgets(line, sizeof(line), _fs_fp)))
122 return (0);
123 /* OLD_STYLE_FSTAB */
124 ++LineNo;
125 if (*line == '#' || *line == '\n')
126 continue;
127 if (!strpbrk(p, " \t")) {
128 _fs_fstab.fs_spec = strsep(&p, ":\n");
129 _fs_fstab.fs_file = strsep(&p, ":\n");
130 fixfsfile();
131 _fs_fstab.fs_type = strsep(&p, ":\n");
132 if (_fs_fstab.fs_type) {
133 if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
134 continue;
135 _fs_fstab.fs_mntops = _fs_fstab.fs_type;
136 _fs_fstab.fs_vfstype =
137 strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
138 "ufs" : "swap";
139 if ((cp = strsep(&p, ":\n")) != NULL) {
140 _fs_fstab.fs_freq = atoi(cp);
141 if ((cp = strsep(&p, ":\n")) != NULL) {
142 _fs_fstab.fs_passno = atoi(cp);
143 return (1);
144 }
145 }
146 }
147 goto bad;
148 }
149 /* OLD_STYLE_FSTAB */
150 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
151 ;
152 _fs_fstab.fs_spec = cp;
153 if (_fs_fstab.fs_spec == NULL || *_fs_fstab.fs_spec == '#')
154 continue;
155 if (strunvis(_fs_fstab.fs_spec, _fs_fstab.fs_spec) < 0)
156 goto bad;
157 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
158 ;
159 _fs_fstab.fs_file = cp;
160 if (_fs_fstab.fs_file == NULL)
161 goto bad;
162 if (strunvis(_fs_fstab.fs_file, _fs_fstab.fs_file) < 0)
163 goto bad;
164 fixfsfile();
165 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
166 ;
167 _fs_fstab.fs_vfstype = cp;
168 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
169 ;
170 _fs_fstab.fs_mntops = cp;
171 if (_fs_fstab.fs_mntops == NULL)
172 goto bad;
173 _fs_fstab.fs_freq = 0;
174 _fs_fstab.fs_passno = 0;
175 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
176 ;
177 if (cp != NULL) {
178 _fs_fstab.fs_freq = atoi(cp);
179 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
180 ;
181 if (cp != NULL)
182 _fs_fstab.fs_passno = atoi(cp);
183 }
184 (void)strlcpy(subline, _fs_fstab.fs_mntops, sizeof(subline));
185 p = subline;
186 for (typexx = 0, cp = strsep(&p, ","); cp;
187 cp = strsep(&p, ",")) {
188 if (strlen(cp) != 2)
189 continue;
190 if (!strcmp(cp, FSTAB_RW)) {
191 _fs_fstab.fs_type = FSTAB_RW;
192 break;
193 }
194 if (!strcmp(cp, FSTAB_RQ)) {
195 _fs_fstab.fs_type = FSTAB_RQ;
196 break;
197 }
198 if (!strcmp(cp, FSTAB_RO)) {
199 _fs_fstab.fs_type = FSTAB_RO;
200 break;
201 }
202 if (!strcmp(cp, FSTAB_SW)) {
203 _fs_fstab.fs_type = FSTAB_SW;
204 break;
205 }
206 if (!strcmp(cp, FSTAB_XX)) {
207 _fs_fstab.fs_type = FSTAB_XX;
208 typexx++;
209 break;
210 }
211 }
212 if (typexx)
213 continue;
214 if (cp != NULL)
215 return (1);
216
217 bad: /* no way to distinguish between EOF and syntax error */
218 error(EFTYPE);
219 }
220 /* NOTREACHED */
221 }
222
223 struct fstab *
getfsent(void)224 getfsent(void)
225 {
226
227 if ((!_fs_fp && !setfsent()) || !fstabscan())
228 return (NULL);
229 return (&_fs_fstab);
230 }
231
232 struct fstab *
getfsspec(const char * name)233 getfsspec(const char *name)
234 {
235
236 if (setfsent())
237 while (fstabscan())
238 if (!strcmp(_fs_fstab.fs_spec, name))
239 return (&_fs_fstab);
240 return (NULL);
241 }
242
243 struct fstab *
getfsfile(const char * name)244 getfsfile(const char *name)
245 {
246
247 if (setfsent())
248 while (fstabscan())
249 if (!strcmp(_fs_fstab.fs_file, name))
250 return (&_fs_fstab);
251 return (NULL);
252 }
253
254 int
setfsent(void)255 setfsent(void)
256 {
257 if (_fs_fp) {
258 rewind(_fs_fp);
259 LineNo = 0;
260 return (1);
261 }
262 if (fsp_set == 0) {
263 if (issetugid())
264 setfstab(NULL);
265 else
266 setfstab(getenv("PATH_FSTAB"));
267 }
268 if ((_fs_fp = fopen(path_fstab, "re")) != NULL) {
269 LineNo = 0;
270 return (1);
271 }
272 error(errno);
273 return (0);
274 }
275
276 void
endfsent(void)277 endfsent(void)
278 {
279
280 if (_fs_fp) {
281 (void)fclose(_fs_fp);
282 _fs_fp = NULL;
283 }
284
285 fsp_set = 0;
286 }
287
288 static void
error(int err)289 error(int err)
290 {
291 char *p;
292 char num[30];
293
294 (void)_write(STDERR_FILENO, "fstab: ", 7);
295 (void)_write(STDERR_FILENO, path_fstab, strlen(path_fstab));
296 (void)_write(STDERR_FILENO, ":", 1);
297 sprintf(num, "%d: ", LineNo);
298 (void)_write(STDERR_FILENO, num, strlen(num));
299 p = strerror(err);
300 (void)_write(STDERR_FILENO, p, strlen(p));
301 (void)_write(STDERR_FILENO, "\n", 1);
302 }
303