1 /* $OpenBSD: mount_tmpfs.c,v 1.7 2018/07/11 07:03:03 martijn Exp $ */ 2 /* $NetBSD: mount_tmpfs.c,v 1.24 2008/08/05 20:57:45 pooka Exp $ */ 3 4 /* 5 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code 10 * 2005 program. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/types.h> 35 #include <sys/mount.h> 36 #include <sys/stat.h> 37 38 #include <ctype.h> 39 #include <err.h> 40 #include <errno.h> 41 #include <grp.h> 42 #include <mntopts.h> 43 #include <pwd.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <unistd.h> 48 #include <limits.h> 49 #include <util.h> 50 51 #include "mount_tmpfs.h" 52 53 /* --------------------------------------------------------------------- */ 54 55 static const struct mntopt mopts[] = { 56 MOPT_STDOPTS, 57 MOPT_WXALLOWED, 58 MOPT_UPDATE, 59 { NULL }, 60 }; 61 62 /* --------------------------------------------------------------------- */ 63 64 static void usage(void) __dead; 65 static uid_t a_uid(const char *); 66 static gid_t a_gid(const char *); 67 static uid_t a_gid(const char *); 68 static int a_num(const char *, const char *); 69 static mode_t a_mask(const char *); 70 static void pathadj(const char *, char *); 71 72 /* --------------------------------------------------------------------- */ 73 74 void 75 mount_tmpfs_parseargs(int argc, char *argv[], 76 struct tmpfs_args *args, int *mntflags, 77 char *canon_dev, char *canon_dir) 78 { 79 int gidset, modeset, uidset; /* Ought to be 'bool'. */ 80 int ch; 81 gid_t gid; 82 uid_t uid; 83 mode_t mode; 84 int64_t tmpnumber; 85 struct stat sb; 86 87 /* Set default values for mount point arguments. */ 88 memset(args, 0, sizeof(*args)); 89 args->ta_version = TMPFS_ARGS_VERSION; 90 args->ta_size_max = 0; 91 args->ta_nodes_max = 0; 92 *mntflags = 0; 93 94 gidset = 0; gid = 0; 95 uidset = 0; uid = 0; 96 modeset = 0; mode = 0; 97 98 optind = optreset = 1; 99 while ((ch = getopt(argc, argv, "g:m:n:o:s:u:")) != -1 ) { 100 switch (ch) { 101 case 'g': 102 gid = a_gid(optarg); 103 gidset = 1; 104 break; 105 106 case 'm': 107 mode = a_mask(optarg); 108 modeset = 1; 109 break; 110 111 case 'n': 112 113 if (scan_scaled(optarg, &tmpnumber) == -1) 114 err(EXIT_FAILURE, "failed to parse nodes `%s'", 115 optarg); 116 args->ta_nodes_max = tmpnumber; 117 break; 118 119 case 'o': 120 getmntopts(optarg, mopts, mntflags); 121 break; 122 123 case 's': 124 if (scan_scaled(optarg, &tmpnumber) == -1) 125 err(EXIT_FAILURE, "failed to parse size `%s'", 126 optarg); 127 args->ta_size_max = tmpnumber; 128 break; 129 130 case 'u': 131 uid = a_uid(optarg); 132 uidset = 1; 133 break; 134 135 case '?': 136 default: 137 usage(); 138 } 139 } 140 argc -= optind; 141 argv += optind; 142 143 if (argc != 2) 144 usage(); 145 146 strlcpy(canon_dev, argv[0], PATH_MAX); 147 pathadj(argv[1], canon_dir); 148 149 if (stat(canon_dir, &sb) == -1) 150 err(EXIT_FAILURE, "cannot stat `%s'", canon_dir); 151 152 args->ta_root_uid = uidset ? uid : sb.st_uid; 153 args->ta_root_gid = gidset ? gid : sb.st_gid; 154 args->ta_root_mode = modeset ? mode : sb.st_mode; 155 } 156 157 /* --------------------------------------------------------------------- */ 158 159 static void 160 usage(void) 161 { 162 extern char *__progname; 163 (void)fprintf(stderr, 164 "usage: %s [-g group] [-m mode] [-n nodes] [-o options] [-s size]\n" 165 " [-u user] tmpfs mount_point\n", __progname); 166 exit(1); 167 } 168 169 /* --------------------------------------------------------------------- */ 170 171 int 172 mount_tmpfs(int argc, char *argv[]) 173 { 174 struct tmpfs_args args; 175 char canon_dev[PATH_MAX], canon_dir[PATH_MAX]; 176 int mntflags; 177 178 mount_tmpfs_parseargs(argc, argv, &args, &mntflags, 179 canon_dev, canon_dir); 180 181 if (mount(MOUNT_TMPFS, canon_dir, mntflags, &args) == -1) 182 err(EXIT_FAILURE, "tmpfs on %s", canon_dir); 183 184 return EXIT_SUCCESS; 185 } 186 187 int 188 main(int argc, char *argv[]) 189 { 190 191 /* setprogname(argv[0]); */ 192 return mount_tmpfs(argc, argv); 193 } 194 195 static uid_t 196 a_uid(const char *s) 197 { 198 struct passwd *pw; 199 200 if ((pw = getpwnam(s)) != NULL) 201 return pw->pw_uid; 202 return a_num(s, "user"); 203 } 204 205 static gid_t 206 a_gid(const char *s) 207 { 208 struct group *gr; 209 210 if ((gr = getgrnam(s)) != NULL) 211 return gr->gr_gid; 212 return a_num(s, "group"); 213 } 214 215 static int 216 a_num(const char *s, const char *id_type) 217 { 218 int id; 219 char *ep; 220 221 id = strtol(s, &ep, 0); 222 if (*ep || s == ep || id < 0) 223 errx(1, "unknown %s id: %s", id_type, s); 224 return id; 225 } 226 227 static mode_t 228 a_mask(const char *s) 229 { 230 int rv; 231 char *ep; 232 233 rv = strtol(s, &ep, 8); 234 if (s == ep || *ep || rv < 0) 235 errx(1, "invalid file mode: %s", s); 236 return rv; 237 } 238 239 static void 240 pathadj(const char *input, char *adjusted) 241 { 242 243 if (realpath(input, adjusted) == NULL) 244 err(1, "realpath %s", input); 245 if (strncmp(input, adjusted, PATH_MAX)) { 246 warnx("\"%s\" is a relative path.", input); 247 warnx("using \"%s\" instead.", adjusted); 248 } 249 } 250