src/veritysetup.c

   1 /*
   2  * veritysetup - setup cryptographic volumes for dm-verity
   3  *
   4  * Copyright (C) 2012, Red Hat, Inc. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #include "cryptsetup.h"
  21
  22 #define PACKAGE_VERITY "veritysetup"
  23
  24 static int use_superblock = 1;
  25
  26 static const char *hash_algorithm = NULL;
  27 static int hash_type = 1;
  28 static int data_block_size = DEFAULT_VERITY_DATA_BLOCK;
  29 static int hash_block_size = DEFAULT_VERITY_HASH_BLOCK;
  30 static uint64_t data_blocks = 0;
  31 static const char *salt_string = NULL;
  32 static uint64_t hash_offset = 0;
  33 static const char *opt_uuid = NULL;
  34
  35 static int opt_version_mode = 0;
  36
  37 static const char **action_argv;
  38 static int action_argc;
  39
  40 static int _prepare_format(struct crypt_params_verity *params,
  41                            const char *data_device,
  42                            uint32_t flags)
  43 {
  44         char *salt = NULL;
  45         int len;
  46
  47         params->hash_name = hash_algorithm ?: DEFAULT_VERITY_HASH;
  48         params->data_device = data_device;
  49
  50         if (salt_string && !strcmp(salt_string, "-")) {
  51                 params->salt_size = 0;
  52                 params->salt = NULL;
  53         } else if (salt_string) {
  54                 len = crypt_hex_to_bytes(salt_string, &salt, 0);
  55                 if (len < 0) {
  56                         log_err(_("Invalid salt string specified.\n"));
  57                         return -EINVAL;
  58                 }
  59                 params->salt_size = len;
  60                 params->salt = salt;
  61         } else {
  62                 params->salt_size = DEFAULT_VERITY_SALT_SIZE;
  63                 params->salt = NULL;
  64         }
  65
  66         params->data_block_size = data_block_size;
  67         params->hash_block_size = hash_block_size;
  68         params->data_size = data_blocks;
  69         params->hash_area_offset = hash_offset;
  70         params->hash_type = hash_type;
  71         params->flags = flags;
  72
  73         return 0;
  74 }
  75
  76 static int action_format(int arg)
  77 {
  78         struct crypt_device *cd = NULL;
  79         struct crypt_params_verity params = {};
  80         uint32_t flags = CRYPT_VERITY_CREATE_HASH;
  81         int r;
  82
  83         /* Try to create hash image if doesn't exist */
  84         r = open(action_argv[1], O_WRONLY | O_EXCL | O_CREAT, S_IRUSR | S_IWUSR);
  85         if (r < 0 && errno != EEXIST) {
  86                 log_err(_("Cannot create hash image %s for writing.\n"), action_argv[1]);
  87                 return -EINVAL;
  88         } else if (r >= 0) {
  89                 log_dbg("Created hash image %s.", action_argv[1]);
  90                 close(r);
  91         }
  92
  93         if ((r = crypt_init(&cd, action_argv[1])))
  94                 goto out;
  95
  96         if (!use_superblock)
  97                 flags |= CRYPT_VERITY_NO_HEADER;
  98
  99         r = _prepare_format(&params, action_argv[0], flags);
 100         if (r < 0)
 101                 goto out;
 102
 103         r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, opt_uuid, NULL, 0, &params);
 104         if (!r)
 105                 crypt_dump(cd);
 106 out:
 107         crypt_free(cd);
 108         free(CONST_CAST(char*)params.salt);
 109         return r;
 110 }
 111
 112 static int _activate(const char *dm_device,
 113                       const char *data_device,
 114                       const char *hash_device,
 115                       const char *root_hash,
 116                       uint32_t flags)
 117 {
 118         struct crypt_device *cd = NULL;
 119         struct crypt_params_verity params = {};
 120         uint32_t activate_flags = CRYPT_ACTIVATE_READONLY;
 121         char *root_hash_bytes = NULL;
 122         ssize_t hash_size;
 123         int r;
 124
 125         if ((r = crypt_init(&cd, hash_device)))
 126                 goto out;
 127
 128         if (use_superblock) {
 129                 params.flags = flags;
 130                 params.hash_area_offset = hash_offset;
 131                 r = crypt_load(cd, CRYPT_VERITY, &params);
 132         } else {
 133                 r = _prepare_format(&params, data_device, flags | CRYPT_VERITY_NO_HEADER);
 134                 if (r < 0)
 135                         goto out;
 136                 r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, NULL, NULL, 0, &params);
 137         }
 138         if (r < 0)
 139                 goto out;
 140         r = crypt_set_data_device(cd, data_device);
 141         if (r < 0)
 142                 goto out;
 143
 144         hash_size = crypt_get_volume_key_size(cd);
 145         if (crypt_hex_to_bytes(root_hash, &root_hash_bytes, 0) != hash_size) {
 146                 log_err(_("Invalid root hash string specified.\n"));
 147                 r = -EINVAL;
 148                 goto out;
 149         }
 150         r = crypt_activate_by_volume_key(cd, dm_device,
 151                                          root_hash_bytes,
 152                                          hash_size,
 153                                          activate_flags);
 154 out:
 155         crypt_free(cd);
 156         free(root_hash_bytes);
 157         free(CONST_CAST(char*)params.salt);
 158         return r;
 159 }
 160
 161 static int action_create(int arg)
 162 {
 163         return _activate(action_argv[0],
 164                          action_argv[1],
 165                          action_argv[2],
 166                          action_argv[3], 0);
 167 }
 168
 169 static int action_verify(int arg)
 170 {
 171         return _activate(NULL,
 172                          action_argv[0],
 173                          action_argv[1],
 174                          action_argv[2],
 175                          CRYPT_VERITY_CHECK_HASH);
 176 }
 177
 178 static int action_remove(int arg)
 179 {
 180         struct crypt_device *cd = NULL;
 181         int r;
 182
 183         r = crypt_init_by_name(&cd, action_argv[0]);
 184         if (r == 0)
 185                 r = crypt_deactivate(cd, action_argv[0]);
 186
 187         crypt_free(cd);
 188         return r;
 189 }
 190
 191 static int action_status(int arg)
 192 {
 193         crypt_status_info ci;
 194         struct crypt_active_device cad;
 195         struct crypt_params_verity vp = {};
 196         struct crypt_device *cd = NULL;
 197         struct stat st;
 198         char *backing_file;
 199         unsigned i, path = 0;
 200         int r = 0;
 201
 202         /* perhaps a path, not a dm device name */
 203         if (strchr(action_argv[0], '/') && !stat(action_argv[0], &st))
 204                 path = 1;
 205
 206         ci = crypt_status(NULL, action_argv[0]);
 207         switch (ci) {
 208         case CRYPT_INVALID:
 209                 r = -EINVAL;
 210                 break;
 211         case CRYPT_INACTIVE:
 212                 if (path)
 213                         log_std("%s is inactive.\n", action_argv[0]);
 214                 else
 215                         log_std("%s/%s is inactive.\n", crypt_get_dir(), action_argv[0]);
 216                 r = -ENODEV;
 217                 break;
 218         case CRYPT_ACTIVE:
 219         case CRYPT_BUSY:
 220                 if (path)
 221                         log_std("%s is active%s.\n", action_argv[0],
 222                                 ci == CRYPT_BUSY ? " and is in use" : "");
 223                 else
 224                         log_std("%s/%s is active%s.\n", crypt_get_dir(), action_argv[0],
 225                                 ci == CRYPT_BUSY ? " and is in use" : "");
 226
 227                 r = crypt_init_by_name_and_header(&cd, action_argv[0], NULL);
 228                 if (r < 0 || !crypt_get_type(cd))
 229                         goto out;
 230
 231                 log_std("  type:        %s\n", crypt_get_type(cd));
 232
 233                 r = crypt_get_active_device(cd, action_argv[0], &cad);
 234                 if (r < 0)
 235                         goto out;
 236
 237                 log_std("  status:      %s\n",
 238                         cad.flags & CRYPT_ACTIVATE_CORRUPTED ? "corrupted" : "verified");
 239
 240                 r = crypt_get_verity_info(cd, &vp);
 241                 if (r < 0)
 242                         goto out;
 243
 244                 log_std("  hash type:   %u\n", vp.hash_type);
 245                 log_std("  data block:  %u\n", vp.data_block_size);
 246                 log_std("  hash block:  %u\n", vp.hash_block_size);
 247                 log_std("  hash name:   %s\n", vp.hash_name);
 248                 log_std("  salt:        ");
 249                 if (vp.salt_size)
 250                         for(i = 0; i < vp.salt_size; i++)
 251                                 log_std("%02hhx", (const char)vp.salt[i]);
 252                 else
 253                         log_std("-");
 254                 log_std("\n");
 255
 256                 log_std("  data device: %s\n", vp.data_device);
 257                 if (crypt_loop_device(vp.data_device)) {
 258                         backing_file = crypt_loop_backing_file(vp.data_device);
 259                         log_std("  data loop:   %s\n", backing_file);
 260                         free(backing_file);
 261                 }
 262                 log_std("  size:        %" PRIu64 " sectors\n", cad.size);
 263                 log_std("  mode:        %s\n", cad.flags & CRYPT_ACTIVATE_READONLY ?
 264                                            "readonly" : "read/write");
 265
 266                 log_std("  hash device: %s\n", vp.hash_device);
 267                 if (crypt_loop_device(vp.hash_device)) {
 268                         backing_file = crypt_loop_backing_file(vp.hash_device);
 269                         log_std("  hash loop:   %s\n", backing_file);
 270                         free(backing_file);
 271                 }
 272                 log_std("  hash offset: %" PRIu64 " sectors\n",
 273                         vp.hash_area_offset * vp.hash_block_size / 512);
 274         }
 275 out:
 276         crypt_free(cd);
 277         if (r == -ENOTSUP)
 278                 r = 0;
 279         return r;
 280 }
 281
 282 static int action_dump(int arg)
 283 {
 284         struct crypt_device *cd = NULL;
 285         struct crypt_params_verity params = {};
 286         int r;
 287
 288         if ((r = crypt_init(&cd, action_argv[0])))
 289                 return r;
 290
 291         params.hash_area_offset = hash_offset;
 292         r = crypt_load(cd, CRYPT_VERITY, &params);
 293         if (!r)
 294                 crypt_dump(cd);
 295         crypt_free(cd);
 296         return r;
 297 }
 298
 299 static struct action_type {
 300         const char *type;
 301         int (*handler)(int);
 302         int required_action_argc;
 303         const char *arg_desc;
 304         const char *desc;
 305 } action_types[] = {
 306         { "format",     action_format, 2, N_("<data_device> <hash_device>"),N_("format device") },
 307         { "verify",     action_verify, 3, N_("<data_device> <hash_device> <root_hash>"),N_("verify device") },
 308         { "create",     action_create, 4, N_("<name> <data_device> <hash_device> <root_hash>"),N_("create active device") },
 309         { "remove",     action_remove, 1, N_("<name>"),N_("remove (deactivate) device") },
 310         { "status",     action_status, 1, N_("<name>"),N_("show active device status") },
 311         { "dump",       action_dump,   1, N_("<hash_device>"),N_("show on-disk information") },
 312         { NULL, NULL, 0, NULL, NULL }
 313 };
 314
 315 static void help(poptContext popt_context,
 316                  enum poptCallbackReason reason __attribute__((unused)),
 317                  struct poptOption *key,
 318                  const char *arg __attribute__((unused)),
 319                  void *data __attribute__((unused)))
 320 {
 321         struct action_type *action;
 322
 323         if (key->shortName == '?') {
 324                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 325                 poptPrintHelp(popt_context, stdout, 0);
 326                 log_std(_("\n"
 327                          "<action> is one of:\n"));
 328                 for(action = action_types; action->type; action++)
 329                         log_std("\t%s %s - %s\n", action->type, _(action->arg_desc), _(action->desc));
 330                 log_std(_("\n"
 331                          "<name> is the device to create under %s\n"
 332                          "<data_device> is the data device\n"
 333                          "<hash_device> is the device containing verification data\n"
 334                          "<root_hash> hash of the root node on <hash_device>\n"),
 335                         crypt_get_dir());
 336
 337                 log_std(_("\nDefault compiled-in dm-verity parameters:\n"
 338                          "\tHash: %s, Data block (bytes): %u, "
 339                          "Hash block (bytes): %u, Salt size: %u, Hash format: %u\n"),
 340                         DEFAULT_VERITY_HASH, DEFAULT_VERITY_DATA_BLOCK,
 341                         DEFAULT_VERITY_HASH_BLOCK, DEFAULT_VERITY_SALT_SIZE,
 342                         1);
 343                 exit(EXIT_SUCCESS);
 344         } else
 345                 usage(popt_context, EXIT_SUCCESS, NULL, NULL);
 346 }
 347
 348 static int run_action(struct action_type *action)
 349 {
 350         int r;
 351
 352         log_dbg("Running command %s.", action->type);
 353
 354         r = action->handler(0);
 355
 356         show_status(r);
 357         return translate_errno(r);
 358 }
 359
 360 int main(int argc, const char **argv)
 361 {
 362         static char *popt_tmp;
 363         static const char *null_action_argv[] = {NULL};
 364         static struct poptOption popt_help_options[] = {
 365                 { NULL,    '\0', POPT_ARG_CALLBACK, help, 0, NULL,                         NULL },
 366                 { "help",  '?',  POPT_ARG_NONE,     NULL, 0, N_("Show this help message"), NULL },
 367                 { "usage", '\0', POPT_ARG_NONE,     NULL, 0, N_("Display brief usage"),    NULL },
 368                 POPT_TABLEEND
 369         };
 370         static struct poptOption popt_options[] = {
 371                 { NULL,              '\0', POPT_ARG_INCLUDE_TABLE, popt_help_options, 0, N_("Help options:"), NULL },
 372                 { "version",         '\0', POPT_ARG_NONE, &opt_version_mode, 0, N_("Print package version"), NULL },
 373                 { "verbose",         'v',  POPT_ARG_NONE, &opt_verbose,      0, N_("Shows more detailed error messages"), NULL },
 374                 { "debug",           '\0', POPT_ARG_NONE, &opt_debug,        0, N_("Show debug messages"), NULL },
 375                 { "no-superblock",   0,    POPT_ARG_VAL,  &use_superblock,   0, N_("Do not use verity superblock"), NULL },
 376                 { "format",          0,    POPT_ARG_INT,  &hash_type,        0, N_("Format type (1 - normal, 0 - original Chrome OS)"), N_("number") },
 377                 { "data-block-size", 0,    POPT_ARG_INT,  &data_block_size,  0, N_("Block size on the data device"), N_("bytes") },
 378                 { "hash-block-size", 0,    POPT_ARG_INT,  &hash_block_size,  0, N_("Block size on the hash device"), N_("bytes") },
 379                 { "data-blocks",     0,    POPT_ARG_STRING, &popt_tmp,       1, N_("The number of blocks in the data file"), N_("blocks") },
 380                 { "hash-offset",     0,    POPT_ARG_STRING, &popt_tmp,       2, N_("Starting offset on the hash device"), N_("bytes") },
 381                 { "hash",            'h',  POPT_ARG_STRING, &hash_algorithm, 0, N_("Hash algorithm"), N_("string") },
 382                 { "salt",            's',  POPT_ARG_STRING, &salt_string,    0, N_("Salt"), N_("hex string") },
 383                 { "uuid",            '\0', POPT_ARG_STRING, &opt_uuid,       0, N_("UUID for device to use."), NULL },
 384                 POPT_TABLEEND
 385         };
 386
 387         poptContext popt_context;
 388         struct action_type *action;
 389         const char *aname;
 390         int r;
 391
 392         crypt_set_log_callback(NULL, tool_log, NULL);
 393
 394         setlocale(LC_ALL, "");
 395         bindtextdomain(PACKAGE, LOCALEDIR);
 396         textdomain(PACKAGE);
 397
 398         popt_context = poptGetContext("verity", argc, argv, popt_options, 0);
 399         poptSetOtherOptionHelp(popt_context,
 400                                _("[OPTION...] <action> <action-specific>"));
 401
 402         while((r = poptGetNextOpt(popt_context)) > 0) {
 403                 unsigned long long ull_value;
 404                 char *endp;
 405
 406                 errno = 0;
 407                 ull_value = strtoull(popt_tmp, &endp, 10);
 408                 if (*endp || !*popt_tmp || !isdigit(*popt_tmp) ||
 409                     (errno == ERANGE && ull_value == ULLONG_MAX) ||
 410                     (errno != 0 && ull_value == 0))
 411                         r = POPT_ERROR_BADNUMBER;
 412
 413                 switch(r) {
 414                         case 1:
 415                                 data_blocks = ull_value;
 416                                 break;
 417                         case 2:
 418                                 hash_offset = ull_value;
 419                                 break;
 420                 }
 421
 422                 if (r < 0)
 423                         break;
 424         }
 425
 426         if (r < -1)
 427                 usage(popt_context, EXIT_FAILURE, poptStrerror(r),
 428                       poptBadOption(popt_context, POPT_BADOPTION_NOALIAS));
 429
 430         if (opt_version_mode) {
 431                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 432                 poptFreeContext(popt_context);
 433                 exit(EXIT_SUCCESS);
 434         }
 435
 436         if (!(aname = poptGetArg(popt_context)))
 437                 usage(popt_context, EXIT_FAILURE, _("Argument <action> missing."),
 438                       poptGetInvocationName(popt_context));
 439         for(action = action_types; action->type; action++)
 440                 if (strcmp(action->type, aname) == 0)
 441                         break;
 442         if (!action->type)
 443                 usage(popt_context, EXIT_FAILURE, _("Unknown action."),
 444                       poptGetInvocationName(popt_context));
 445
 446         action_argc = 0;
 447         action_argv = poptGetArgs(popt_context);
 448         /* Make return values of poptGetArgs more consistent in case of remaining argc = 0 */
 449         if(!action_argv)
 450                 action_argv = null_action_argv;
 451
 452         /* Count args, somewhat unnice, change? */
 453         while(action_argv[action_argc] != NULL)
 454                 action_argc++;
 455
 456         if(action_argc < action->required_action_argc) {
 457                 char buf[128];
 458                 snprintf(buf, 128,_("%s: requires %s as arguments"), action->type, action->arg_desc);
 459                 usage(popt_context, EXIT_FAILURE, buf,
 460                       poptGetInvocationName(popt_context));
 461         }
 462
 463         if (data_block_size < 0 || hash_block_size < 0 || hash_type < 0) {
 464                 usage(popt_context, EXIT_FAILURE,
 465                       _("Negative number for option not permitted."),
 466                       poptGetInvocationName(popt_context));
 467         }
 468
 469         if (opt_debug) {
 470                 opt_verbose = 1;
 471                 crypt_set_debug_level(-1);
 472                 dbg_version_and_cmd(argc, argv);
 473         }
 474
 475         r = run_action(action);
 476         poptFreeContext(popt_context);
 477         return r;
 478 }