util/grub-mount.c

   1 /* grub-mount.c - FUSE driver for filesystems that GRUB understands */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2008,2009,2010 Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #define FUSE_USE_VERSION 26
  20 #include <config.h>
  21 #include <grub/types.h>
  22 #include <grub/emu/misc.h>
  23 #include <grub/util/misc.h>
  24 #include <grub/misc.h>
  25 #include <grub/device.h>
  26 #include <grub/disk.h>
  27 #include <grub/file.h>
  28 #include <grub/fs.h>
  29 #include <grub/env.h>
  30 #include <grub/term.h>
  31 #include <grub/mm.h>
  32 #include <grub/lib/hexdump.h>
  33 #include <grub/crypto.h>
  34 #include <grub/command.h>
  35 #include <grub/zfs/zfs.h>
  36 #include <grub/i18n.h>
  37 #include <fuse/fuse.h>
  38
  39 #include <stdio.h>
  40 #include <unistd.h>
  41 #include <string.h>
  42 #include <stdlib.h>
  43
  44 #pragma GCC diagnostic ignored "-Wmissing-prototypes"
  45 #pragma GCC diagnostic ignored "-Wmissing-declarations"
  46 #include <argp.h>
  47 #pragma GCC diagnostic error "-Wmissing-prototypes"
  48 #pragma GCC diagnostic error "-Wmissing-declarations"
  49
  50 #include "progname.h"
  51
  52 static const char *root = NULL;
  53 grub_device_t dev = NULL;
  54 grub_fs_t fs = NULL;
  55 static char **images = NULL;
  56 static char *debug_str = NULL;
  57 static char **fuse_args = NULL;
  58 static int fuse_argc = 0;
  59 static int num_disks = 0;
  60 static int mount_crypt = 0;
  61
  62 static grub_err_t
  63 execute_command (const char *name, int n, char **args)
  64 {
  65   grub_command_t cmd;
  66
  67   cmd = grub_command_find (name);
  68   if (! cmd)
  69     grub_util_error (_("can't find command `%s'"), name);
  70
  71   return (cmd->func) (cmd, n, args);
  72 }
  73
  74 /* Translate GRUB error numbers into OS error numbers.  Print any unexpected
  75    errors.  */
  76 static int
  77 translate_error (void)
  78 {
  79   int ret;
  80
  81   switch (grub_errno)
  82     {
  83       case GRUB_ERR_NONE:
  84         ret = 0;
  85         break;
  86
  87       case GRUB_ERR_OUT_OF_MEMORY:
  88         grub_print_error ();
  89         ret = -ENOMEM;
  90         break;
  91
  92       case GRUB_ERR_BAD_FILE_TYPE:
  93         /* This could also be EISDIR.  Take a guess.  */
  94         ret = -ENOTDIR;
  95         break;
  96
  97       case GRUB_ERR_FILE_NOT_FOUND:
  98         ret = -ENOENT;
  99         break;
 100
 101       case GRUB_ERR_FILE_READ_ERROR:
 102       case GRUB_ERR_READ_ERROR:
 103       case GRUB_ERR_IO:
 104         grub_print_error ();
 105         ret = -EIO;
 106         break;
 107
 108       case GRUB_ERR_SYMLINK_LOOP:
 109         ret = -ELOOP;
 110         break;
 111
 112       default:
 113         grub_print_error ();
 114         ret = -EINVAL;
 115         break;
 116     }
 117
 118   /* Any previous errors were handled.  */
 119   grub_errno = GRUB_ERR_NONE;
 120
 121   return ret;
 122 }
 123
 124 /* Context for fuse_getattr.  */
 125 struct fuse_getattr_ctx
 126 {
 127   char *filename;
 128   struct grub_dirhook_info file_info;
 129   int file_exists;
 130 };
 131
 132 /* A hook for iterating directories. */
 133 static int
 134 fuse_getattr_find_file (const char *cur_filename,
 135                         const struct grub_dirhook_info *info, void *data)
 136 {
 137   struct fuse_getattr_ctx *ctx = data;
 138
 139   if ((info->case_insensitive ? grub_strcasecmp (cur_filename, ctx->filename)
 140        : grub_strcmp (cur_filename, ctx->filename)) == 0)
 141     {
 142       ctx->file_info = *info;
 143       ctx->file_exists = 1;
 144       return 1;
 145     }
 146   return 0;
 147 }
 148
 149 static int
 150 fuse_getattr (const char *path, struct stat *st)
 151 {
 152   struct fuse_getattr_ctx ctx;
 153   char *pathname, *path2;
 154
 155   if (path[0] == '/' && path[1] == 0)
 156     {
 157       st->st_dev = 0;
 158       st->st_ino = 0;
 159       st->st_mode = 0555 | S_IFDIR;
 160       st->st_uid = 0;
 161       st->st_gid = 0;
 162       st->st_rdev = 0;
 163       st->st_size = 0;
 164       st->st_blksize = 512;
 165       st->st_blocks = (st->st_blksize + 511) >> 9;
 166       st->st_atime = st->st_mtime = st->st_ctime = 0;
 167       return 0;
 168     }
 169
 170   ctx.file_exists = 0;
 171
 172   pathname = xstrdup (path);
 173
 174   /* Remove trailing '/'. */
 175   while (*pathname && pathname[grub_strlen (pathname) - 1] == '/')
 176     pathname[grub_strlen (pathname) - 1] = 0;
 177
 178   /* Split into path and filename. */
 179   ctx.filename = grub_strrchr (pathname, '/');
 180   if (! ctx.filename)
 181     {
 182       path2 = grub_strdup ("/");
 183       ctx.filename = pathname;
 184     }
 185   else
 186     {
 187       ctx.filename++;
 188       path2 = grub_strdup (pathname);
 189       path2[ctx.filename - pathname] = 0;
 190     }
 191
 192   /* It's the whole device. */
 193   (fs->fs_dir) (dev, path2, fuse_getattr_find_file, &ctx);
 194
 195   grub_free (path2);
 196   if (!ctx.file_exists)
 197     {
 198       grub_errno = GRUB_ERR_NONE;
 199       return -ENOENT;
 200     }
 201   st->st_dev = 0;
 202   st->st_ino = 0;
 203   st->st_mode = ctx.file_info.dir ? (0555 | S_IFDIR) : (0444 | S_IFREG);
 204   st->st_uid = 0;
 205   st->st_gid = 0;
 206   st->st_rdev = 0;
 207   st->st_size = 0;
 208   if (!ctx.file_info.dir)
 209     {
 210       grub_file_t file;
 211       file = grub_file_open (path, GRUB_FILE_TYPE_GET_SIZE);
 212       if (! file && grub_errno == GRUB_ERR_BAD_FILE_TYPE)
 213         {
 214           grub_errno = GRUB_ERR_NONE;
 215           st->st_mode = (0555 | S_IFDIR);
 216         }
 217       else if (! file)
 218         return translate_error ();
 219       else
 220         {
 221           st->st_size = file->size;
 222           grub_file_close (file);
 223         }
 224     }
 225   st->st_blksize = 512;
 226   st->st_blocks = (st->st_size + 511) >> 9;
 227   st->st_atime = st->st_mtime = st->st_ctime = ctx.file_info.mtimeset
 228     ? ctx.file_info.mtime : 0;
 229   grub_errno = GRUB_ERR_NONE;
 230   return 0;
 231 }
 232
 233 static int
 234 fuse_opendir (const char *path, struct fuse_file_info *fi)
 235 {
 236   return 0;
 237 }
 238
 239 /* FIXME */
 240 static grub_file_t files[65536];
 241 static int first_fd = 1;
 242
 243 static int
 244 fuse_open (const char *path, struct fuse_file_info *fi __attribute__ ((unused)))
 245 {
 246   grub_file_t file;
 247   file = grub_file_open (path, GRUB_FILE_TYPE_MOUNT);
 248   if (! file)
 249     return translate_error ();
 250   files[first_fd++] = file;
 251   fi->fh = first_fd;
 252   files[first_fd++] = file;
 253   grub_errno = GRUB_ERR_NONE;
 254   return 0;
 255 }
 256
 257 static int
 258 fuse_read (const char *path, char *buf, size_t sz, off_t off,
 259            struct fuse_file_info *fi)
 260 {
 261   grub_file_t file = files[fi->fh];
 262   grub_ssize_t size;
 263
 264   if (off > file->size)
 265     return -EINVAL;
 266
 267   file->offset = off;
 268
 269   size = grub_file_read (file, buf, sz);
 270   if (size < 0)
 271     return translate_error ();
 272   else
 273     {
 274       grub_errno = GRUB_ERR_NONE;
 275       return size;
 276     }
 277 }
 278
 279 static int
 280 fuse_release (const char *path, struct fuse_file_info *fi)
 281 {
 282   grub_file_close (files[fi->fh]);
 283   files[fi->fh] = NULL;
 284   grub_errno = GRUB_ERR_NONE;
 285   return 0;
 286 }
 287
 288 /* Context for fuse_readdir.  */
 289 struct fuse_readdir_ctx
 290 {
 291   const char *path;
 292   void *buf;
 293   fuse_fill_dir_t fill;
 294 };
 295
 296 /* Helper for fuse_readdir.  */
 297 static int
 298 fuse_readdir_call_fill (const char *filename,
 299                         const struct grub_dirhook_info *info, void *data)
 300 {
 301   struct fuse_readdir_ctx *ctx = data;
 302   struct stat st;
 303
 304   grub_memset (&st, 0, sizeof (st));
 305   st.st_mode = info->dir ? (0555 | S_IFDIR) : (0444 | S_IFREG);
 306   if (!info->dir)
 307     {
 308       grub_file_t file;
 309       char *tmp;
 310       tmp = xasprintf ("%s/%s", ctx->path, filename);
 311       file = grub_file_open (tmp, GRUB_FILE_TYPE_GET_SIZE);
 312       free (tmp);
 313       /* Symlink to directory.  */
 314       if (! file && grub_errno == GRUB_ERR_BAD_FILE_TYPE)
 315         {
 316           grub_errno = GRUB_ERR_NONE;
 317           st.st_mode = (0555 | S_IFDIR);
 318         }
 319       else if (!file)
 320         {
 321           grub_errno = GRUB_ERR_NONE;
 322         }
 323       else
 324         {
 325           st.st_size = file->size;
 326           grub_file_close (file);
 327         }
 328     }
 329   st.st_blksize = 512;
 330   st.st_blocks = (st.st_size + 511) >> 9;
 331   st.st_atime = st.st_mtime = st.st_ctime
 332     = info->mtimeset ? info->mtime : 0;
 333   ctx->fill (ctx->buf, filename, &st, 0);
 334   return 0;
 335 }
 336
 337 static int
 338 fuse_readdir (const char *path, void *buf,
 339               fuse_fill_dir_t fill, off_t off, struct fuse_file_info *fi)
 340 {
 341   struct fuse_readdir_ctx ctx = {
 342     .path = path,
 343     .buf = buf,
 344     .fill = fill
 345   };
 346   char *pathname;
 347
 348   pathname = xstrdup (path);
 349
 350   /* Remove trailing '/'. */
 351   while (pathname [0] && pathname[1]
 352          && pathname[grub_strlen (pathname) - 1] == '/')
 353     pathname[grub_strlen (pathname) - 1] = 0;
 354
 355   (fs->fs_dir) (dev, pathname, fuse_readdir_call_fill, &ctx);
 356   free (pathname);
 357   grub_errno = GRUB_ERR_NONE;
 358   return 0;
 359 }
 360
 361 struct fuse_operations grub_opers = {
 362   .getattr = fuse_getattr,
 363   .open = fuse_open,
 364   .release = fuse_release,
 365   .opendir = fuse_opendir,
 366   .readdir = fuse_readdir,
 367   .read = fuse_read
 368 };
 369
 370 static grub_err_t
 371 fuse_init (void)
 372 {
 373   int i;
 374
 375   for (i = 0; i < num_disks; i++)
 376     {
 377       char *argv[2];
 378       char *host_file;
 379       char *loop_name;
 380       loop_name = grub_xasprintf ("loop%d", i);
 381       if (!loop_name)
 382         grub_util_error ("%s", grub_errmsg);
 383
 384       host_file = grub_xasprintf ("(host)%s", images[i]);
 385       if (!host_file)
 386         grub_util_error ("%s", grub_errmsg);
 387
 388       argv[0] = loop_name;
 389       argv[1] = host_file;
 390
 391       if (execute_command ("loopback", 2, argv))
 392         grub_util_error (_("`loopback' command fails: %s"), grub_errmsg);
 393
 394       grub_free (loop_name);
 395       grub_free (host_file);
 396     }
 397
 398   if (mount_crypt)
 399     {
 400       char *argv[2] = { xstrdup ("-a"), NULL};
 401       if (execute_command ("cryptomount", 1, argv))
 402           grub_util_error (_("`cryptomount' command fails: %s"),
 403                            grub_errmsg);
 404       free (argv[0]);
 405     }
 406
 407   grub_lvm_fini ();
 408   grub_mdraid09_fini ();
 409   grub_mdraid1x_fini ();
 410   grub_diskfilter_fini ();
 411   grub_diskfilter_init ();
 412   grub_mdraid09_init ();
 413   grub_mdraid1x_init ();
 414   grub_lvm_init ();
 415
 416   dev = grub_device_open (0);
 417   if (! dev)
 418     return grub_errno;
 419
 420   fs = grub_fs_probe (dev);
 421   if (! fs)
 422     {
 423       grub_device_close (dev);
 424       return grub_errno;
 425     }
 426
 427   if (fuse_main (fuse_argc, fuse_args, &grub_opers, NULL))
 428     grub_error (GRUB_ERR_IO, "fuse_main failed");
 429
 430   for (i = 0; i < num_disks; i++)
 431     {
 432       char *argv[2];
 433       char *loop_name;
 434
 435       loop_name = grub_xasprintf ("loop%d", i);
 436       if (!loop_name)
 437         grub_util_error ("%s", grub_errmsg);
 438
 439       argv[0] = xstrdup ("-d");
 440       argv[1] = loop_name;
 441
 442       execute_command ("loopback", 2, argv);
 443
 444       grub_free (argv[0]);
 445       grub_free (loop_name);
 446     }
 447
 448   return grub_errno;
 449 }
 450
 451 static struct argp_option options[] = {
 452   {"root",      'r', N_("DEVICE_NAME"), 0, N_("Set root device."),                 2},
 453   {"debug",     'd', N_("STRING"),           0, N_("Set debug environment variable."),  2},
 454   {"crypto",   'C', NULL, 0, N_("Mount crypto devices."), 2},
 455   {"zfs-key",      'K',
 456    /* TRANSLATORS: "prompt" is a keyword.  */
 457    N_("FILE|prompt"), 0, N_("Load zfs crypto key."),                 2},
 458   {"verbose",   'v', NULL, 0, N_("print verbose messages."), 2},
 459   {0, 0, 0, 0, 0, 0}
 460 };
 461
 462 /* Print the version information.  */
 463 static void
 464 print_version (FILE *stream, struct argp_state *state)
 465 {
 466   fprintf (stream, "%s (%s) %s\n", program_name, PACKAGE_NAME, PACKAGE_VERSION);
 467 }
 468 void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
 469
 470 static error_t
 471 argp_parser (int key, char *arg, struct argp_state *state)
 472 {
 473   switch (key)
 474     {
 475     case 'r':
 476       root = arg;
 477       return 0;
 478
 479     case 'K':
 480       if (strcmp (arg, "prompt") == 0)
 481         {
 482           char buf[1024];
 483           grub_printf ("%s", _("Enter ZFS password: "));
 484           if (grub_password_get (buf, 1023))
 485             {
 486               grub_zfs_add_key ((grub_uint8_t *) buf, grub_strlen (buf), 1);
 487             }
 488         }
 489       else
 490         {
 491           FILE *f;
 492           ssize_t real_size;
 493           grub_uint8_t buf[1024];
 494           f = grub_util_fopen (arg, "rb");
 495           if (!f)
 496             {
 497               printf (_("%s: error:"), program_name);
 498               printf (_("cannot open `%s': %s"), arg, strerror (errno));
 499               printf ("\n");
 500               return 0;
 501             }
 502           real_size = fread (buf, 1, 1024, f);
 503           if (real_size < 0)
 504             {
 505               printf (_("%s: error:"), program_name);
 506               printf (_("cannot read `%s': %s"), arg,
 507                       strerror (errno));
 508               printf ("\n");
 509               fclose (f);
 510               return 0;
 511             }
 512           grub_zfs_add_key (buf, real_size, 0);
 513           fclose (f);
 514         }
 515       return 0;
 516
 517     case 'C':
 518       mount_crypt = 1;
 519       return 0;
 520
 521     case 'd':
 522       debug_str = arg;
 523       return 0;
 524
 525     case 'v':
 526       verbosity++;
 527       return 0;
 528
 529     case ARGP_KEY_ARG:
 530       if (arg[0] != '-')
 531         break;
 532
 533     /* FALLTHROUGH */
 534     default:
 535       if (!arg)
 536         return 0;
 537
 538       fuse_args = xrealloc (fuse_args, (fuse_argc + 1) * sizeof (fuse_args[0]));
 539       fuse_args[fuse_argc] = xstrdup (arg);
 540       fuse_argc++;
 541       return 0;
 542     }
 543
 544   images = xrealloc (images, (num_disks + 1) * sizeof (images[0]));
 545   images[num_disks] = grub_canonicalize_file_name (arg);
 546   num_disks++;
 547
 548   return 0;
 549 }
 550
 551 struct argp argp = {
 552   options, argp_parser, N_("IMAGE1 [IMAGE2 ...] MOUNTPOINT"),
 553   N_("Debug tool for filesystem driver."),
 554   NULL, NULL, NULL
 555 };
 556
 557 int
 558 main (int argc, char *argv[])
 559 {
 560   const char *default_root;
 561   char *alloc_root;
 562
 563   grub_util_host_init (&argc, &argv);
 564
 565   fuse_args = xrealloc (fuse_args, (fuse_argc + 2) * sizeof (fuse_args[0]));
 566   fuse_args[fuse_argc] = xstrdup (argv[0]);
 567   fuse_argc++;
 568   /* Run single-threaded.  */
 569   fuse_args[fuse_argc] = xstrdup ("-s");
 570   fuse_argc++;
 571
 572   argp_parse (&argp, argc, argv, 0, 0, 0);
 573
 574   if (num_disks < 2)
 575     grub_util_error ("%s", _("need an image and mountpoint"));
 576   fuse_args = xrealloc (fuse_args, (fuse_argc + 2) * sizeof (fuse_args[0]));
 577   fuse_args[fuse_argc] = images[num_disks - 1];
 578   fuse_argc++;
 579   num_disks--;
 580   fuse_args[fuse_argc] = NULL;
 581
 582   /* Initialize all modules. */
 583   grub_init_all ();
 584
 585   if (debug_str)
 586     grub_env_set ("debug", debug_str);
 587
 588   default_root = (num_disks == 1) ? "loop0" : "md0";
 589   alloc_root = 0;
 590   if (root)
 591     {
 592       if ((*root >= '0') && (*root <= '9'))
 593         {
 594           alloc_root = xmalloc (strlen (default_root) + strlen (root) + 2);
 595
 596           sprintf (alloc_root, "%s,%s", default_root, root);
 597           root = alloc_root;
 598         }
 599     }
 600   else
 601     root = default_root;
 602
 603   grub_env_set ("root", root);
 604
 605   if (alloc_root)
 606     free (alloc_root);
 607
 608   /* Do it.  */
 609   fuse_init ();
 610   if (grub_errno)
 611     {
 612       grub_print_error ();
 613       return 1;
 614     }
 615
 616   /* Free resources.  */
 617   grub_fini_all ();
 618
 619   return 0;
 620 }