xref: /netbsd-src/sbin/mount_tmpfs/mount_tmpfs.c (revision 2980e352a13e8f0b545a366830c411e7a542ada8)
1 /*	$NetBSD: mount_tmpfs.c,v 1.23 2008/07/28 12:42:12 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Julio M. Merino Vidal, developed as part of Google's Summer of Code
9  * 2005 program.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 #ifndef lint
35 __RCSID("$NetBSD: mount_tmpfs.c,v 1.23 2008/07/28 12:42:12 pooka Exp $");
36 #endif /* not lint */
37 
38 #include <sys/param.h>
39 #include <sys/mount.h>
40 #include <sys/stat.h>
41 
42 #include <fs/tmpfs/tmpfs_args.h>
43 
44 #include <ctype.h>
45 #include <err.h>
46 #include <errno.h>
47 #include <grp.h>
48 #include <mntopts.h>
49 #include <pwd.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54 #include "fattr.h"
55 
56 /* --------------------------------------------------------------------- */
57 
58 static const struct mntopt mopts[] = {
59 	MOPT_STDOPTS,
60 	MOPT_GETARGS,
61 	MOPT_NULL,
62 };
63 
64 /* --------------------------------------------------------------------- */
65 
66 static int	mount_tmpfs(int argc, char **argv);
67 static void	usage(void) __dead;
68 
69 /* --------------------------------------------------------------------- */
70 
71 int
72 mount_tmpfs(int argc, char *argv[])
73 {
74 	char canon_dir[MAXPATHLEN];
75 	int gidset, modeset, uidset; /* Ought to be 'bool'. */
76 	int ch, mntflags;
77 	gid_t gid;
78 	uid_t uid;
79 	mode_t mode;
80 	int64_t tmpnumber;
81 	mntoptparse_t mp;
82 	struct tmpfs_args args;
83 	struct stat sb;
84 
85 	setprogname(argv[0]);
86 
87 	/* Set default values for mount point arguments. */
88 	args.ta_version = TMPFS_ARGS_VERSION;
89 	args.ta_size_max = 0;
90 	args.ta_nodes_max = 0;
91 	mntflags = 0;
92 
93 	gidset = 0; gid = 0;
94 	uidset = 0; uid = 0;
95 	modeset = 0; mode = 0;
96 
97 	optind = optreset = 1;
98 	while ((ch = getopt(argc, argv, "g:m:n:o:s:u:")) != -1 ) {
99 		switch (ch) {
100 		case 'g':
101 			gid = a_gid(optarg);
102 			gidset = 1;
103 			break;
104 
105 		case 'm':
106 			mode = a_mask(optarg);
107 			modeset = 1;
108 			break;
109 
110 		case 'n':
111 			if (dehumanize_number(optarg, &tmpnumber) == -1)
112 				err(EXIT_FAILURE, "failed to parse nodes `%s'",
113 				    optarg);
114 			args.ta_nodes_max = tmpnumber;
115 			break;
116 
117 		case 'o':
118 			mp = getmntopts(optarg, mopts, &mntflags, 0);
119 			if (mp == NULL)
120 				err(EXIT_FAILURE, "getmntopts");
121 			freemntopts(mp);
122 			break;
123 
124 		case 's':
125 			if (dehumanize_number(optarg, &tmpnumber) == -1)
126 				err(EXIT_FAILURE, "failed to parse size `%s'",
127 				    optarg);
128 			args.ta_size_max = tmpnumber;
129 			break;
130 
131 		case 'u':
132 			uid = a_uid(optarg);
133 			uidset = 1;
134 			break;
135 
136 		case '?':
137 		default:
138 			usage();
139 		}
140 	}
141 	argc -= optind;
142 	argv += optind;
143 
144 	if (argc != 2)
145 		usage();
146 
147 	if (realpath(argv[1], canon_dir) == NULL)
148 		err(EXIT_FAILURE, "realpath %s", argv[1]);
149 
150 	if (strncmp(argv[1], canon_dir, MAXPATHLEN) != 0) {
151 		warnx("\"%s\" is a relative path", argv[1]);
152 		warnx("using \"%s\" instead", canon_dir);
153 	}
154 
155 	if (stat(canon_dir, &sb) == -1)
156 		err(EXIT_FAILURE, "cannot stat `%s'", canon_dir);
157 
158 	args.ta_root_uid = uidset ? uid : sb.st_uid;
159 	args.ta_root_gid = gidset ? gid : sb.st_gid;
160 	args.ta_root_mode = modeset ? mode : sb.st_mode;
161 
162 	if (mount(MOUNT_TMPFS, canon_dir, mntflags, &args, sizeof args) == -1)
163 		err(EXIT_FAILURE, "tmpfs on %s", canon_dir);
164 
165 	if (mntflags & MNT_GETARGS) {
166 		struct passwd *pw;
167 		struct group *gr;
168 
169 		(void)printf("version=%d, ", args.ta_version);
170 		(void)printf("size_max=%" PRIuMAX ", ",
171 		    (uintmax_t)args.ta_size_max);
172 		(void)printf("nodes_max=%" PRIuMAX ", ",
173 		    (uintmax_t)args.ta_nodes_max);
174 
175 		pw = getpwuid(args.ta_root_uid);
176 		if (pw == NULL)
177 			(void)printf("root_uid=%" PRIuMAX ", ",
178 			    (uintmax_t)args.ta_root_uid);
179 		else
180 			(void)printf("root_uid=%s, ", pw->pw_name);
181 
182 		gr = getgrgid(args.ta_root_gid);
183 		if (gr == NULL)
184 			(void)printf("root_gid=%" PRIuMAX ", ",
185 			    (uintmax_t)args.ta_root_gid);
186 		else
187 			(void)printf("root_gid=%s, ", gr->gr_name);
188 
189 		(void)printf("root_mode=%o\n", args.ta_root_mode);
190 	}
191 
192 	return EXIT_SUCCESS;
193 }
194 
195 /* --------------------------------------------------------------------- */
196 
197 static void
198 usage(void)
199 {
200 	(void)fprintf(stderr,
201 	    "Usage: %s [-g group] [-m mode] [-n nodes] [-o options] [-s size]\n"
202 	    "           [-u user] tmpfs mountpoint\n", getprogname());
203 	exit(1);
204 }
205 
206 /* --------------------------------------------------------------------- */
207 
208 #ifndef MOUNT_NOMAIN
209 int
210 main(int argc, char *argv[])
211 {
212 
213 	return mount_tmpfs(argc, argv);
214 }
215 #endif
216