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