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 <stdio.h>
  21 #include <stdlib.h>
  22 #include <stdarg.h>
  23 #include <errno.h>
  24 #include <string.h>
  25 #include <ctype.h>
  26 #include <inttypes.h>
  27 #include <popt.h>
  28 #include <limits.h>
  29 #include <sys/types.h>
  30 #include <sys/stat.h>
  31 #include <fcntl.h>
  32
  33 #include "cryptsetup.h"
  34
  35 #define PACKAGE_VERITY "veritysetup"
  36
  37 static int use_superblock = 1;
  38
  39 static const char *hash_algorithm = NULL;
  40 static int hash_type = 1;
  41 static int data_block_size = DEFAULT_VERITY_DATA_BLOCK;
  42 static int hash_block_size = DEFAULT_VERITY_HASH_BLOCK;
  43 static uint64_t data_blocks = 0;
  44 static const char *salt_string = NULL;
  45 static uint64_t hash_offset = 0;
  46 static const char *opt_uuid = NULL;
  47
  48 static int opt_verbose = 0;
  49 static int opt_debug = 0;
  50 static int opt_version_mode = 0;
  51
  52 static const char **action_argv;
  53 static int action_argc;
  54
  55 __attribute__((format(printf, 5, 6)))
  56 static void clogger(struct crypt_device *cd, int level, const char *file,
  57                    int line, const char *format, ...)
  58 {
  59         va_list argp;
  60         char *target = NULL;
  61
  62         va_start(argp, format);
  63
  64         if (vasprintf(&target, format, argp) > 0) {
  65                 if (level >= 0) {
  66                         crypt_log(cd, level, target);
  67 #ifdef CRYPT_DEBUG
  68                 } else if (opt_debug)
  69                         printf("# %s:%d %s\n", file ?: "?", line, target);
  70 #else
  71                 } else if (opt_debug)
  72                         printf("# %s\n", target);
  73 #endif
  74         }
  75
  76         va_end(argp);
  77         free(target);
  78 }
  79
  80 static void _log(int level, const char *msg, void *usrptr __attribute__((unused)))
  81 {
  82         switch(level) {
  83
  84         case CRYPT_LOG_NORMAL:
  85                 fputs(msg, stdout);
  86                 break;
  87         case CRYPT_LOG_VERBOSE:
  88                 if (opt_verbose)
  89                         fputs(msg, stdout);
  90                 break;
  91         case CRYPT_LOG_ERROR:
  92                 fputs(msg, stderr);
  93                 break;
  94         case CRYPT_LOG_DEBUG:
  95                 if (opt_debug)
  96                         printf("# %s\n", msg);
  97                 break;
  98         default:
  99                 fprintf(stderr, "Internal error on logging class for msg: %s", msg);
 100                 break;
 101         }
 102 }
 103
 104 static int _prepare_format(struct crypt_params_verity *params,
 105                            const char *data_device,
 106                            uint32_t flags)
 107 {
 108         char *salt = NULL;
 109         int len;
 110
 111         params->hash_name = hash_algorithm ?: DEFAULT_VERITY_HASH;
 112         params->data_device = data_device;
 113
 114         if (salt_string && !strcmp(salt_string, "-")) {
 115                 params->salt_size = 0;
 116                 params->salt = NULL;
 117         } else if (salt_string) {
 118                 len = crypt_hex_to_bytes(salt_string, &salt, 0);
 119                 if (len < 0) {
 120                         log_err(_("Invalid salt string specified.\n"));
 121                         return -EINVAL;
 122                 }
 123                 params->salt_size = len;
 124                 params->salt = salt;
 125         } else {
 126                 params->salt_size = DEFAULT_VERITY_SALT_SIZE;
 127                 params->salt = NULL;
 128         }
 129
 130         params->data_block_size = data_block_size;
 131         params->hash_block_size = hash_block_size;
 132         params->data_size = data_blocks;
 133         params->hash_area_offset = hash_offset;
 134         params->hash_type = hash_type;
 135         params->flags = flags;
 136
 137         return 0;
 138 }
 139
 140 static int action_format(int arg)
 141 {
 142         struct crypt_device *cd = NULL;
 143         struct crypt_params_verity params = {};
 144         uint32_t flags = CRYPT_VERITY_CREATE_HASH;
 145         struct stat st;
 146         int r;
 147
 148         /* Try to create hash image if doesn't exist */
 149         if (stat(action_argv[1], &st) < 0) {
 150                 log_dbg("Creating hash image %s.", action_argv[1]);
 151                 r = open(action_argv[1], O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
 152                 if (r < 0) {
 153                         log_err(_("Cannot create hash image %s for writing.\n"), action_argv[1]);
 154                         return -EINVAL;
 155                 }
 156                 close(r);
 157         }
 158
 159         if ((r = crypt_init(&cd, action_argv[1])))
 160                 goto out;
 161
 162         if (!use_superblock)
 163                 flags |= CRYPT_VERITY_NO_HEADER;
 164
 165         r = _prepare_format(&params, action_argv[0], flags);
 166         if (r < 0)
 167                 goto out;
 168
 169         r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, opt_uuid, NULL, 0, &params);
 170         if (!r)
 171                 crypt_dump(cd);
 172 out:
 173         crypt_free(cd);
 174         free(CONST_CAST(char*)params.salt);
 175         return r;
 176 }
 177
 178 static int _activate(const char *dm_device,
 179                       const char *data_device,
 180                       const char *hash_device,
 181                       const char *root_hash,
 182                       uint32_t flags)
 183 {
 184         struct crypt_device *cd = NULL;
 185         struct crypt_params_verity params = {};
 186         uint32_t activate_flags = CRYPT_ACTIVATE_READONLY;
 187         char *root_hash_bytes = NULL;
 188         ssize_t hash_size;
 189         int r;
 190
 191         if ((r = crypt_init(&cd, hash_device)))
 192                 goto out;
 193
 194         if (use_superblock) {
 195                 params.flags = flags;
 196                 params.hash_area_offset = hash_offset;
 197                 r = crypt_load(cd, CRYPT_VERITY, &params);
 198         } else {
 199                 r = _prepare_format(&params, data_device, flags | CRYPT_VERITY_NO_HEADER);
 200                 if (r < 0)
 201                         goto out;
 202                 r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, NULL, NULL, 0, &params);
 203         }
 204         if (r < 0)
 205                 goto out;
 206         r = crypt_set_data_device(cd, data_device);
 207         if (r < 0)
 208                 goto out;
 209
 210         hash_size = crypt_get_volume_key_size(cd);
 211         if (crypt_hex_to_bytes(root_hash, &root_hash_bytes, 0) != hash_size) {
 212                 log_err(_("Invalid root hash string specified.\n"));
 213                 r = -EINVAL;
 214                 goto out;
 215         }
 216         r = crypt_activate_by_volume_key(cd, dm_device,
 217                                          root_hash_bytes,
 218                                          hash_size,
 219                                          activate_flags);
 220 out:
 221         crypt_free(cd);
 222         free(root_hash_bytes);
 223         free(CONST_CAST(char*)params.salt);
 224         return r;
 225 }
 226
 227 static int action_create(int arg)
 228 {
 229         return _activate(action_argv[0],
 230                          action_argv[1],
 231                          action_argv[2],
 232                          action_argv[3], 0);
 233 }
 234
 235 static int action_verify(int arg)
 236 {
 237         return _activate(NULL,
 238                          action_argv[0],
 239                          action_argv[1],
 240                          action_argv[2],
 241                          CRYPT_VERITY_CHECK_HASH);
 242 }
 243
 244 static int action_remove(int arg)
 245 {
 246         struct crypt_device *cd = NULL;
 247         int r;
 248
 249         r = crypt_init_by_name(&cd, action_argv[0]);
 250         if (r == 0)
 251                 r = crypt_deactivate(cd, action_argv[0]);
 252
 253         crypt_free(cd);
 254         return r;
 255 }
 256
 257 static int action_status(int arg)
 258 {
 259         crypt_status_info ci;
 260         struct crypt_active_device cad;
 261         struct crypt_params_verity vp = {};
 262         struct crypt_device *cd = NULL;
 263         struct stat st;
 264         char *backing_file;
 265         unsigned i, path = 0;
 266         int r = 0;
 267
 268         /* perhaps a path, not a dm device name */
 269         if (strchr(action_argv[0], '/') && !stat(action_argv[0], &st))
 270                 path = 1;
 271
 272         ci = crypt_status(NULL, action_argv[0]);
 273         switch (ci) {
 274         case CRYPT_INVALID:
 275                 r = -EINVAL;
 276                 break;
 277         case CRYPT_INACTIVE:
 278                 if (path)
 279                         log_std("%s is inactive.\n", action_argv[0]);
 280                 else
 281                         log_std("%s/%s is inactive.\n", crypt_get_dir(), action_argv[0]);
 282                 r = -ENODEV;
 283                 break;
 284         case CRYPT_ACTIVE:
 285         case CRYPT_BUSY:
 286                 if (path)
 287                         log_std("%s is active%s.\n", action_argv[0],
 288                                 ci == CRYPT_BUSY ? " and is in use" : "");
 289                 else
 290                         log_std("%s/%s is active%s.\n", crypt_get_dir(), action_argv[0],
 291                                 ci == CRYPT_BUSY ? " and is in use" : "");
 292
 293                 r = crypt_init_by_name_and_header(&cd, action_argv[0], NULL);
 294                 if (r < 0 || !crypt_get_type(cd))
 295                         goto out;
 296
 297                 log_std("  type:        %s\n", crypt_get_type(cd));
 298
 299                 r = crypt_get_active_device(cd, action_argv[0], &cad);
 300                 if (r < 0)
 301                         goto out;
 302
 303                 log_std("  status:      %s\n",
 304                         cad.flags & CRYPT_ACTIVATE_CORRUPTED ? "corrupted" : "verified");
 305
 306                 r = crypt_get_verity_info(cd, &vp);
 307                 if (r < 0)
 308                         goto out;
 309
 310                 log_std("  hash type:   %u\n", vp.hash_type);
 311                 log_std("  data block:  %u\n", vp.data_block_size);
 312                 log_std("  hash block:  %u\n", vp.hash_block_size);
 313                 log_std("  hash name:   %s\n", vp.hash_name);
 314                 log_std("  salt:        ");
 315                 if (vp.salt_size)
 316                         for(i = 0; i < vp.salt_size; i++)
 317                                 log_std("%02hhx", (const char)vp.salt[i]);
 318                 else
 319                         log_std("-");
 320                 log_std("\n");
 321
 322                 log_std("  data device: %s\n", vp.data_device);
 323                 if (crypt_loop_device(vp.data_device)) {
 324                         backing_file = crypt_loop_backing_file(vp.data_device);
 325                         log_std("  data loop:   %s\n", backing_file);
 326                         free(backing_file);
 327                 }
 328                 log_std("  size:        %" PRIu64 " sectors\n", cad.size);
 329                 log_std("  mode:        %s\n", cad.flags & CRYPT_ACTIVATE_READONLY ?
 330                                            "readonly" : "read/write");
 331
 332                 log_std("  hash device: %s\n", vp.hash_device);
 333                 if (crypt_loop_device(vp.hash_device)) {
 334                         backing_file = crypt_loop_backing_file(vp.hash_device);
 335                         log_std("  hash loop:   %s\n", backing_file);
 336                         free(backing_file);
 337                 }
 338                 log_std("  hash offset: %" PRIu64 " sectors\n",
 339                         vp.hash_area_offset * vp.hash_block_size / 512);
 340         }
 341 out:
 342         crypt_free(cd);
 343         if (r == -ENOTSUP)
 344                 r = 0;
 345         return r;
 346 }
 347
 348 static int action_dump(int arg)
 349 {
 350         struct crypt_device *cd = NULL;
 351         struct crypt_params_verity params = {};
 352         int r;
 353
 354         if ((r = crypt_init(&cd, action_argv[0])))
 355                 return r;
 356
 357         params.hash_area_offset = hash_offset;
 358         r = crypt_load(cd, CRYPT_VERITY, &params);
 359         if (!r)
 360                 crypt_dump(cd);
 361         crypt_free(cd);
 362         return r;
 363 }
 364
 365 static __attribute__ ((noreturn)) void usage(poptContext popt_context,
 366                                              int exitcode, const char *error,
 367                                              const char *more)
 368 {
 369         poptPrintUsage(popt_context, stderr, 0);
 370         if (error)
 371                 log_err("%s: %s\n", more, error);
 372         poptFreeContext(popt_context);
 373         exit(exitcode);
 374 }
 375
 376 static void _dbg_version_and_cmd(int argc, const char **argv)
 377 {
 378         int i;
 379
 380         log_std("# %s %s processing \"", PACKAGE_VERITY, PACKAGE_VERSION);
 381         for (i = 0; i < argc; i++) {
 382                 if (i)
 383                         log_std(" ");
 384                 log_std("%s", argv[i]);
 385         }
 386         log_std("\"\n");
 387 }
 388
 389 static struct action_type {
 390         const char *type;
 391         int (*handler)(int);
 392         int required_action_argc;
 393         const char *arg_desc;
 394         const char *desc;
 395 } action_types[] = {
 396         { "format",     action_format, 2, N_("<data_device> <hash_device>"),N_("format device") },
 397         { "verify",     action_verify, 3, N_("<data_device> <hash_device> <root_hash>"),N_("verify device") },
 398         { "create",     action_create, 4, N_("<name> <data_device> <hash_device> <root_hash>"),N_("create active device") },
 399         { "remove",     action_remove, 1, N_("<name>"),N_("remove (deactivate) device") },
 400         { "status",     action_status, 1, N_("<name>"),N_("show active device status") },
 401         { "dump",       action_dump,   1, N_("<hash_device>"),N_("show on-disk information") },
 402         { NULL, NULL, 0, NULL, NULL }
 403 };
 404
 405 static void help(poptContext popt_context,
 406                  enum poptCallbackReason reason __attribute__((unused)),
 407                  struct poptOption *key,
 408                  const char *arg __attribute__((unused)),
 409                  void *data __attribute__((unused)))
 410 {
 411         struct action_type *action;
 412
 413         if (key->shortName == '?') {
 414                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 415                 poptPrintHelp(popt_context, stdout, 0);
 416                 log_std(_("\n"
 417                          "<action> is one of:\n"));
 418                 for(action = action_types; action->type; action++)
 419                         log_std("\t%s %s - %s\n", action->type, _(action->arg_desc), _(action->desc));
 420                 log_std(_("\n"
 421                          "<name> is the device to create under %s\n"
 422                          "<data_device> is the data device\n"
 423                          "<hash_device> is the device containing verification data\n"
 424                          "<root_hash> hash of the root node on <hash_device>\n"),
 425                         crypt_get_dir());
 426
 427                 log_std(_("\nDefault compiled-in dm-verity parameters:\n"
 428                          "\tHash: %s, Data block (bytes): %u, "
 429                          "Hash block (bytes): %u, Salt size: %u, Hash format: %u\n"),
 430                         DEFAULT_VERITY_HASH, DEFAULT_VERITY_DATA_BLOCK,
 431                         DEFAULT_VERITY_HASH_BLOCK, DEFAULT_VERITY_SALT_SIZE,
 432                         1);
 433                 exit(EXIT_SUCCESS);
 434         } else
 435                 usage(popt_context, EXIT_SUCCESS, NULL, NULL);
 436 }
 437
 438 static void show_status(int errcode)
 439 {
 440         char error[256], *error_;
 441
 442         if(!opt_verbose)
 443                 return;
 444
 445         if(!errcode) {
 446                 log_std(_("Command successful.\n"));
 447                 return;
 448         }
 449
 450         crypt_get_error(error, sizeof(error));
 451
 452         if (!error[0]) {
 453                 error_ = strerror_r(-errcode, error, sizeof(error));
 454                 if (error_ != error) {
 455                         strncpy(error, error_, sizeof(error));
 456                         error[sizeof(error) - 1] = '\0';
 457                 }
 458         }
 459
 460         log_err(_("Command failed with code %i"), -errcode);
 461         if (*error)
 462                 log_err(": %s\n", error);
 463         else
 464                 log_err(".\n");
 465 }
 466
 467 static int run_action(struct action_type *action)
 468 {
 469         int r;
 470
 471         log_dbg("Running command %s.", action->type);
 472
 473         r = action->handler(0);
 474
 475         show_status(r);
 476
 477         /* Translate exit code to simple codes */
 478         switch (r) {
 479         case 0:         r = EXIT_SUCCESS; break;
 480         case -EEXIST:
 481         case -EBUSY:    r = 5; break;
 482         case -ENOTBLK:
 483         case -ENODEV:   r = 4; break;
 484         case -ENOMEM:   r = 3; break;
 485         case -EPERM:    r = 2; break;
 486         case -EINVAL:
 487         case -ENOENT:
 488         case -ENOSYS:
 489         default:        r = EXIT_FAILURE;
 490         }
 491         return r;
 492 }
 493
 494 int main(int argc, const char **argv)
 495 {
 496         static char *popt_tmp;
 497         static const char *null_action_argv[] = {NULL};
 498         static struct poptOption popt_help_options[] = {
 499                 { NULL,    '\0', POPT_ARG_CALLBACK, help, 0, NULL,                         NULL },
 500                 { "help",  '?',  POPT_ARG_NONE,     NULL, 0, N_("Show this help message"), NULL },
 501                 { "usage", '\0', POPT_ARG_NONE,     NULL, 0, N_("Display brief usage"),    NULL },
 502                 POPT_TABLEEND
 503         };
 504         static struct poptOption popt_options[] = {
 505                 { NULL,              '\0', POPT_ARG_INCLUDE_TABLE, popt_help_options, 0, N_("Help options:"), NULL },
 506                 { "version",         '\0', POPT_ARG_NONE, &opt_version_mode, 0, N_("Print package version"), NULL },
 507                 { "verbose",         'v',  POPT_ARG_NONE, &opt_verbose,      0, N_("Shows more detailed error messages"), NULL },
 508                 { "debug",           '\0', POPT_ARG_NONE, &opt_debug,        0, N_("Show debug messages"), NULL },
 509                 { "no-superblock",   0,    POPT_ARG_VAL,  &use_superblock,   0, N_("Do not use verity superblock"), NULL },
 510                 { "format",          0,    POPT_ARG_INT,  &hash_type,        0, N_("Format type (1 - normal, 0 - original Chrome OS)"), N_("number") },
 511                 { "data-block-size", 0,    POPT_ARG_INT,  &data_block_size,  0, N_("Block size on the data device"), N_("bytes") },
 512                 { "hash-block-size", 0,    POPT_ARG_INT,  &hash_block_size,  0, N_("Block size on the hash device"), N_("bytes") },
 513                 { "data-blocks",     0,    POPT_ARG_STRING, &popt_tmp,       1, N_("The number of blocks in the data file"), N_("blocks") },
 514                 { "hash-offset",     0,    POPT_ARG_STRING, &popt_tmp,       2, N_("Starting offset on the hash device"), N_("bytes") },
 515                 { "hash",            'h',  POPT_ARG_STRING, &hash_algorithm, 0, N_("Hash algorithm"), N_("string") },
 516                 { "salt",            's',  POPT_ARG_STRING, &salt_string,    0, N_("Salt"), N_("hex string") },
 517                 { "uuid",            '\0', POPT_ARG_STRING, &opt_uuid,       0, N_("UUID for device to use."), NULL },
 518                 POPT_TABLEEND
 519         };
 520
 521         poptContext popt_context;
 522         struct action_type *action;
 523         const char *aname;
 524         int r;
 525
 526         crypt_set_log_callback(NULL, _log, NULL);
 527
 528         setlocale(LC_ALL, "");
 529         bindtextdomain(PACKAGE, LOCALEDIR);
 530         textdomain(PACKAGE);
 531
 532         popt_context = poptGetContext("verity", argc, argv, popt_options, 0);
 533         poptSetOtherOptionHelp(popt_context,
 534                                _("[OPTION...] <action> <action-specific>"));
 535
 536         while((r = poptGetNextOpt(popt_context)) > 0) {
 537                 unsigned long long ull_value;
 538                 char *endp;
 539
 540                 errno = 0;
 541                 ull_value = strtoull(popt_tmp, &endp, 10);
 542                 if (*endp || !*popt_tmp || !isdigit(*popt_tmp) ||
 543                     (errno == ERANGE && ull_value == ULLONG_MAX) ||
 544                     (errno != 0 && ull_value == 0))
 545                         r = POPT_ERROR_BADNUMBER;
 546
 547                 switch(r) {
 548                         case 1:
 549                                 data_blocks = ull_value;
 550                                 break;
 551                         case 2:
 552                                 hash_offset = ull_value;
 553                                 break;
 554                 }
 555
 556                 if (r < 0)
 557                         break;
 558         }
 559
 560         if (r < -1)
 561                 usage(popt_context, EXIT_FAILURE, poptStrerror(r),
 562                       poptBadOption(popt_context, POPT_BADOPTION_NOALIAS));
 563
 564         if (opt_version_mode) {
 565                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 566                 poptFreeContext(popt_context);
 567                 exit(EXIT_SUCCESS);
 568         }
 569
 570         if (!(aname = poptGetArg(popt_context)))
 571                 usage(popt_context, EXIT_FAILURE, _("Argument <action> missing."),
 572                       poptGetInvocationName(popt_context));
 573         for(action = action_types; action->type; action++)
 574                 if (strcmp(action->type, aname) == 0)
 575                         break;
 576         if (!action->type)
 577                 usage(popt_context, EXIT_FAILURE, _("Unknown action."),
 578                       poptGetInvocationName(popt_context));
 579
 580         action_argc = 0;
 581         action_argv = poptGetArgs(popt_context);
 582         /* Make return values of poptGetArgs more consistent in case of remaining argc = 0 */
 583         if(!action_argv)
 584                 action_argv = null_action_argv;
 585
 586         /* Count args, somewhat unnice, change? */
 587         while(action_argv[action_argc] != NULL)
 588                 action_argc++;
 589
 590         if(action_argc < action->required_action_argc) {
 591                 char buf[128];
 592                 snprintf(buf, 128,_("%s: requires %s as arguments"), action->type, action->arg_desc);
 593                 usage(popt_context, EXIT_FAILURE, buf,
 594                       poptGetInvocationName(popt_context));
 595         }
 596
 597         if (data_block_size < 0 || hash_block_size < 0 || hash_type < 0) {
 598                 usage(popt_context, EXIT_FAILURE,
 599                       _("Negative number for option not permitted."),
 600                       poptGetInvocationName(popt_context));
 601         }
 602
 603         if (opt_debug) {
 604                 opt_verbose = 1;
 605                 crypt_set_debug_level(-1);
 606                 _dbg_version_and_cmd(argc, argv);
 607         }
 608
 609         r = run_action(action);
 610         poptFreeContext(popt_context);
 611         return r;
 612 }