sbin/mount_tmpfs/mount_tmpfs.c

   1 /*      $NetBSD: mount_tmpfs.c,v 1.24 2008/08/05 20:57:45 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/param.h>
  34 #include <sys/mount.h>
  35 #include <sys/stat.h>
  36
  37 #include <vfs/tmpfs/tmpfs_mount.h>
  38
  39 #include <ctype.h>
  40 #include <err.h>
  41 #include <errno.h>
  42 #include <grp.h>
  43 #include <mntopts.h>
  44 #include <pwd.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <sysexits.h>
  49 #include <unistd.h>
  50 #include <inttypes.h>
  51 #include <libutil.h>
  52
  53 #include "defs.h"
  54 #include "mount_tmpfs.h"
  55
  56 /* --------------------------------------------------------------------- */
  57
  58 #define MOPT_TMPFSOPTS  \
  59         { "gid=",       0,      MNT_GID, 1},    \
  60         { "uid=",       0,      MNT_UID, 1},    \
  61         { "mode=",      0,      MNT_MODE, 1},   \
  62         { "inodes=",    0,      MNT_INODES, 1}, \
  63         { "size=",      0,      MNT_SIZE, 1},   \
  64         { "maxfilesize=",       0,      MNT_MAXFSIZE, 1}
  65
  66
  67 static const struct mntopt mopts[] = {
  68         MOPT_STDOPTS,
  69         MOPT_TMPFSOPTS,
  70         MOPT_NULL
  71 };
  72
  73 static int Cflag;
  74
  75 /* --------------------------------------------------------------------- */
  76
  77 static gid_t    a_gid(char *);
  78 static uid_t    a_uid(char *);
  79 static mode_t   a_mask(char *);
  80 static int64_t a_number(char *s);
  81 static void     usage(void) __dead2;
  82
  83 /* --------------------------------------------------------------------- */
  84
  85 void
  86 mount_tmpfs_parseargs(int argc, char *argv[],
  87         struct tmpfs_mount_info *args, int *mntflags,
  88         char *canon_dev, char *canon_dir)
  89 {
  90         int gidset, modeset, uidset; /* Ought to be 'bool'. */
  91         int ch;
  92         gid_t gid;
  93         uid_t uid;
  94         mode_t mode;
  95         struct stat sb;
  96         int extend_flags = 0;
  97         char *ptr, *delim;
  98
  99         /* Set default values for mount point arguments. */
 100         memset(args, 0, sizeof(*args));
 101         args->ta_version = TMPFS_ARGS_VERSION;
 102         args->ta_size_max = 0;
 103         args->ta_nodes_max = 0;
 104         args->ta_maxfsize_max = 0;
 105         *mntflags = 0;
 106
 107         gidset = 0; gid = 0;
 108         uidset = 0; uid = 0;
 109         modeset = 0; mode = 0;
 110
 111         optind = optreset = 1;
 112         while ((ch = getopt(argc, argv, "Cf:g:m:n:o:s:u:")) != -1 ) {
 113                 switch (ch) {
 114                 case 'C':
 115                         Cflag = 1;
 116                         break;
 117                 case 'f':
 118                         args->ta_maxfsize_max = a_number(optarg);
 119                         break;
 120
 121                 case 'g':
 122                         gid = a_gid(optarg);
 123                         gidset = 1;
 124                         break;
 125
 126                 case 'm':
 127                         mode = a_mask(optarg);
 128                         modeset = 1;
 129                         break;
 130
 131                 case 'n':
 132                         args->ta_nodes_max = a_number(optarg);
 133                         break;
 134
 135                 case 'o':
 136                         getmntopts(optarg, mopts, mntflags, &extend_flags);
 137                         if (extend_flags & MNT_GID) {
 138                                 ptr = strstr(optarg, "gid=");
 139                                 if(ptr) {
 140                                         delim = strstr(ptr, ",");
 141                                         if (delim) {
 142                                                 *delim = '\0';
 143                                                 gid = a_gid(ptr + 4);
 144                                                 *delim = ',';
 145                                         } else
 146                                                 gid = a_gid(ptr + 4);
 147                                         gidset = 1;
 148                                 }
 149                                 extend_flags ^= MNT_GID;
 150                         }
 151                         if (extend_flags & MNT_UID) {
 152                                 ptr = strstr(optarg, "uid=");
 153                                 if(ptr) {
 154                                         delim = strstr(ptr, ",");
 155                                         if (delim) {
 156                                                 *delim = '\0';
 157                                                 uid = a_uid(ptr + 4);
 158                                                 *delim = ',';
 159                                         } else
 160                                                 uid = a_uid(ptr + 4);
 161                                         uidset = 1;
 162                                 }
 163                                 extend_flags ^= MNT_UID;
 164                         }
 165                         if (extend_flags & MNT_MODE) {
 166                                 ptr = strstr(optarg, "mode=");
 167                                 if(ptr) {
 168                                         delim = strstr(ptr, ",");
 169                                         if (delim) {
 170                                                 *delim = '\0';
 171                                                 mode = a_mask(ptr + 5);
 172                                                 *delim = ',';
 173                                         } else
 174                                                 mode = a_mask(ptr + 5);
 175                                         modeset = 1;
 176                                 }
 177                                 extend_flags ^= MNT_MODE;
 178                         }
 179                         if (extend_flags & MNT_INODES) {
 180                                 ptr = strstr(optarg, "inodes=");
 181                                 if(ptr) {
 182                                         delim = strstr(ptr, ",");
 183                                         if (delim) {
 184                                                 *delim = '\0';
 185                                                 args->ta_nodes_max = a_number(ptr + 7);
 186                                                 *delim = ',';
 187                                         } else
 188                                                 args->ta_nodes_max = a_number(ptr + 7);
 189                                 }
 190                                 extend_flags ^= MNT_INODES;
 191                         }
 192                         if (extend_flags & MNT_SIZE) {
 193                                 ptr = strstr(optarg, "size=");
 194                                 if(ptr) {
 195                                         delim = strstr(ptr, ",");
 196                                         if (delim) {
 197                                                 *delim = '\0';
 198                                                 args->ta_size_max = a_number(ptr + 5);
 199                                                 *delim = ',';
 200                                         } else
 201                                                 args->ta_size_max = a_number(ptr + 5);
 202                                 }
 203                                 extend_flags ^= MNT_SIZE;
 204                         }
 205                         if (extend_flags & MNT_MAXFSIZE) {
 206                                 ptr = strstr(optarg, "maxfilesize=");
 207                                 if(ptr) {
 208                                         delim = strstr(ptr, ",");
 209                                         if (delim) {
 210                                                 *delim = '\0';
 211                                                 args->ta_maxfsize_max = a_number(ptr + 12);
 212                                                 *delim = ',';
 213                                         } else
 214                                                 args->ta_maxfsize_max = a_number(ptr + 12);
 215                                 }
 216                                 extend_flags ^= MNT_MAXFSIZE;
 217                         }
 218                         break;
 219
 220                 case 's':
 221                         args->ta_size_max = a_number(optarg);
 222                         break;
 223
 224                 case 'u':
 225                         uid = a_uid(optarg);
 226                         uidset = 1;
 227                         break;
 228
 229                 case '?':
 230                 default:
 231                         usage();
 232                 }
 233         }
 234         argc -= optind;
 235         argv += optind;
 236
 237         if (argc != 2)
 238                 usage();
 239
 240         strlcpy(canon_dev, argv[0], MAXPATHLEN);
 241         strlcpy(canon_dir, argv[1], MAXPATHLEN);
 242
 243         if (stat(canon_dir, &sb) == -1)
 244                 err(EXIT_FAILURE, "cannot stat `%s'", canon_dir);
 245
 246         args->ta_root_uid = uidset ? uid : sb.st_uid;
 247         args->ta_root_gid = gidset ? gid : sb.st_gid;
 248         args->ta_root_mode = modeset ? mode : sb.st_mode;
 249 }
 250
 251 /* --------------------------------------------------------------------- */
 252
 253 static gid_t
 254 a_gid(char *s)
 255 {
 256         struct group *gr;
 257         char *gname;
 258         gid_t gid;
 259
 260         if ((gr = getgrnam(s)) != NULL)
 261                 gid = gr->gr_gid;
 262         else {
 263                 for (gname = s; *s && isdigit(*s); ++s);
 264                 if (!*s)
 265                         gid = atoi(gname);
 266                 else
 267                         errx(EX_NOUSER, "unknown group id: %s", gname);
 268         }
 269         return (gid);
 270 }
 271
 272 static uid_t
 273 a_uid(char *s)
 274 {
 275         struct passwd *pw;
 276         char *uname;
 277         uid_t uid;
 278
 279         if ((pw = getpwnam(s)) != NULL)
 280                 uid = pw->pw_uid;
 281         else {
 282                 for (uname = s; *s && isdigit(*s); ++s);
 283                 if (!*s)
 284                         uid = atoi(uname);
 285                 else
 286                         errx(EX_NOUSER, "unknown user id: %s", uname);
 287         }
 288         return (uid);
 289 }
 290
 291 static mode_t
 292 a_mask(char *s)
 293 {
 294         int done, rv = 0;
 295         char *ep;
 296
 297         done = 0;
 298         if (*s >= '0' && *s <= '7') {
 299                 done = 1;
 300                 rv = strtol(s, &ep, 8);
 301         }
 302         if (!done || rv < 0 || *ep)
 303                 errx(EX_USAGE, "invalid file mode: %s", s);
 304         return (rv);
 305 }
 306
 307 static int64_t
 308 a_number(char *s)
 309 {
 310         int64_t rv = 0;
 311
 312         if (dehumanize_number(s, &rv) < 0 || rv < 0)
 313                 errx(EX_USAGE, "bad number for option: %s", s);
 314         return (rv);
 315 }
 316
 317 static void
 318 usage(void)
 319 {
 320         fprintf(stderr,
 321             "Usage: %s [-C] [-g group] [-m mode] [-n nodes] [-o options] [-s size]\n"
 322             "           [-u user] [-f maxfilesize] tmpfs mountpoint\n", getprogname());
 323         exit(1);
 324 }
 325
 326 /* --------------------------------------------------------------------- */
 327
 328 int
 329 mount_tmpfs(int argc, char *argv[])
 330 {
 331         struct tmpfs_mount_info args;
 332         char canon_dev[MAXPATHLEN], canon_dir[MAXPATHLEN];
 333         int mntflags;
 334         struct vfsconf vfc;
 335         int error;
 336         fsnode_t copyroot = NULL;
 337         fsnode_t copyhlinks = NULL;
 338
 339         mount_tmpfs_parseargs(argc, argv, &args, &mntflags,
 340             canon_dev, canon_dir);
 341
 342         error = getvfsbyname("tmpfs", &vfc);
 343         if (error && vfsisloadable("tmpfs")) {
 344                 if(vfsload("tmpfs"))
 345                         err(EX_OSERR, "vfsload(%s)", "tmpfs");
 346                 endvfsent();
 347                 error = getvfsbyname("tmpfs", &vfc);
 348         }
 349         if (error)
 350                 errx(EX_OSERR, "%s filesystem not available", "tmpfs");
 351
 352         if (Cflag)
 353                 copyroot = FSCopy(&copyhlinks, canon_dir);
 354
 355         if (mount(vfc.vfc_name, canon_dir, mntflags, &args) == -1)
 356                 err(EXIT_FAILURE, "tmpfs on %s", canon_dir);
 357
 358         if (Cflag)
 359                 FSPaste(canon_dir, copyroot, copyhlinks);
 360
 361         return EXIT_SUCCESS;
 362 }
 363
 364 #ifndef MOUNT_NOMAIN
 365 int
 366 main(int argc, char *argv[])
 367 {
 368         setprogname(argv[0]);
 369         return mount_tmpfs(argc, argv);
 370 }
 371 #endif