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 <inttypes.h>
  26 #include <popt.h>
  27 #include <limits.h>
  28 #include <sys/stat.h>
  29
  30 #include "cryptsetup.h"
  31
  32 #define PACKAGE_VERITY "veritysetup"
  33
  34 static int use_superblock = 1;
  35
  36 static const char *hash_algorithm = NULL;
  37 static int hash_type = 1;
  38 static int data_block_size = DEFAULT_VERITY_DATA_BLOCK;
  39 static int hash_block_size = DEFAULT_VERITY_HASH_BLOCK;
  40 static uint64_t data_blocks = 0;
  41 static const char *salt_string = NULL;
  42 static uint64_t hash_start = 0;
  43 static const char *opt_uuid = NULL;
  44
  45 static int opt_verbose = 0;
  46 static int opt_debug = 0;
  47 static int opt_version_mode = 0;
  48
  49 static const char **action_argv;
  50 static int action_argc;
  51
  52 static size_t hex_to_bytes(const char *hex, char *result)
  53 {
  54         char buf[3] = "xx\0", *endp;
  55         size_t i, len;
  56
  57         len = strlen(hex) / 2;
  58         for (i = 0; i < len; i++) {
  59                 memcpy(buf, &hex[i * 2], 2);
  60                 result[i] = strtoul(buf, &endp, 16);
  61                 if (endp != &buf[2])
  62                         return -EINVAL;
  63         }
  64         return i;
  65 }
  66
  67 __attribute__((format(printf, 5, 6)))
  68 static void clogger(struct crypt_device *cd, int level, const char *file,
  69                    int line, const char *format, ...)
  70 {
  71         va_list argp;
  72         char *target = NULL;
  73
  74         va_start(argp, format);
  75
  76         if (vasprintf(&target, format, argp) > 0) {
  77                 if (level >= 0) {
  78                         crypt_log(cd, level, target);
  79 #ifdef CRYPT_DEBUG
  80                 } else if (opt_debug)
  81                         printf("# %s:%d %s\n", file ?: "?", line, target);
  82 #else
  83                 } else if (opt_debug)
  84                         printf("# %s\n", target);
  85 #endif
  86         }
  87
  88         va_end(argp);
  89         free(target);
  90 }
  91
  92 static void _log(int level, const char *msg, void *usrptr __attribute__((unused)))
  93 {
  94         switch(level) {
  95
  96         case CRYPT_LOG_NORMAL:
  97                 fputs(msg, stdout);
  98                 break;
  99         case CRYPT_LOG_VERBOSE:
 100                 if (opt_verbose)
 101                         fputs(msg, stdout);
 102                 break;
 103         case CRYPT_LOG_ERROR:
 104                 fputs(msg, stderr);
 105                 break;
 106         case CRYPT_LOG_DEBUG:
 107                 if (opt_debug)
 108                         printf("# %s\n", msg);
 109                 break;
 110         default:
 111                 fprintf(stderr, "Internal error on logging class for msg: %s", msg);
 112                 break;
 113         }
 114 }
 115
 116 static int _prepare_format(struct crypt_params_verity *params,
 117                            const char *data_device,
 118                            uint32_t flags)
 119 {
 120         static char salt_bytes[512];
 121
 122         params->hash_name = hash_algorithm ?: DEFAULT_VERITY_HASH;
 123         params->data_device = data_device;
 124
 125         if (salt_string && !strcmp(salt_string, "-")) {
 126                 params->salt_size = 0;
 127                 params->salt = NULL;
 128         } else if (salt_string) {
 129                 params->salt_size = strlen(salt_string) / 2;
 130                 if (hex_to_bytes(salt_string, salt_bytes) != params->salt_size)
 131                         return -EINVAL;
 132                 params->salt = salt_bytes;
 133         } else
 134                 params->salt_size = DEFAULT_VERITY_SALT_SIZE;
 135
 136         params->data_block_size = data_block_size;
 137         params->hash_block_size = hash_block_size;
 138         params->data_size = data_blocks;
 139         params->hash_area_offset = hash_start;
 140         params->hash_type = hash_type;
 141         params->flags = flags;
 142
 143         return 0;
 144 }
 145
 146 static int action_format(int arg)
 147 {
 148         struct crypt_device *cd = NULL;
 149         struct crypt_params_verity params = {};
 150         uint32_t flags = CRYPT_VERITY_CREATE_HASH;
 151         int r;
 152
 153         if ((r = crypt_init(&cd, action_argv[1])))
 154                 goto out;
 155
 156         if (!use_superblock)
 157                 flags |= CRYPT_VERITY_NO_HEADER;
 158
 159         r = _prepare_format(&params, action_argv[0], flags);
 160         if (r < 0)
 161                 goto out;
 162
 163         r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, opt_uuid, NULL, 0, &params);
 164         if (!r)
 165                 crypt_dump(cd);
 166 out:
 167         crypt_free(cd);
 168         return r;
 169 }
 170
 171 static int _activate(const char *dm_device,
 172                       const char *data_device,
 173                       const char *hash_device,
 174                       const char *root_hash,
 175                       uint32_t flags)
 176 {
 177         struct crypt_device *cd = NULL;
 178         struct crypt_params_verity params = {};
 179         uint32_t activate_flags = CRYPT_ACTIVATE_READONLY;
 180         char root_hash_bytes[128];
 181         size_t hash_size;
 182         int r;
 183
 184         if ((r = crypt_init(&cd, hash_device)))
 185                 goto out;
 186
 187         if (use_superblock) {
 188                 params.flags = flags;
 189                 params.hash_area_offset = hash_start;
 190                 r = crypt_load(cd, CRYPT_VERITY, &params);
 191         } else {
 192                 r = _prepare_format(&params, data_device, flags | CRYPT_VERITY_NO_HEADER);
 193                 if (r < 0)
 194                         goto out;
 195                 r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, NULL, NULL, 0, &params);
 196         }
 197         if (r < 0)
 198                 goto out;
 199         r = crypt_set_data_device(cd, data_device);
 200         if (r < 0)
 201                 goto out;
 202
 203         hash_size = crypt_get_volume_key_size(cd);
 204         if (hex_to_bytes(root_hash, root_hash_bytes) != hash_size) {
 205                 r = -EINVAL;
 206                 goto out;
 207         }
 208         r = crypt_activate_by_volume_key(cd, dm_device,
 209                                          root_hash_bytes,
 210                                          hash_size,
 211                                          activate_flags);
 212 out:
 213         crypt_free(cd);
 214         return r;
 215 }
 216
 217 static int action_create(int arg)
 218 {
 219         return _activate(action_argv[0],
 220                          action_argv[1],
 221                          action_argv[2],
 222                          action_argv[3], 0);
 223 }
 224
 225 static int action_verify(int arg)
 226 {
 227         return _activate(NULL,
 228                          action_argv[0],
 229                          action_argv[1],
 230                          action_argv[2],
 231                          CRYPT_VERITY_CHECK_HASH);
 232 }
 233
 234 static int action_remove(int arg)
 235 {
 236         struct crypt_device *cd = NULL;
 237         int r;
 238
 239         r = crypt_init_by_name(&cd, action_argv[0]);
 240         if (r == 0)
 241                 r = crypt_deactivate(cd, action_argv[0]);
 242
 243         crypt_free(cd);
 244         return r;
 245 }
 246
 247 static int action_status(int arg)
 248 {
 249         crypt_status_info ci;
 250         struct crypt_active_device cad;
 251         struct crypt_params_verity vp = {};
 252         struct crypt_device *cd = NULL;
 253         struct stat st;
 254         char *backing_file;
 255         unsigned i, path = 0;
 256         int r = 0;
 257
 258         /* perhaps a path, not a dm device name */
 259         if (strchr(action_argv[0], '/') && !stat(action_argv[0], &st))
 260                 path = 1;
 261
 262         ci = crypt_status(NULL, action_argv[0]);
 263         switch (ci) {
 264         case CRYPT_INVALID:
 265                 r = -EINVAL;
 266                 break;
 267         case CRYPT_INACTIVE:
 268                 if (path)
 269                         log_std("%s is inactive.\n", action_argv[0]);
 270                 else
 271                         log_std("%s/%s is inactive.\n", crypt_get_dir(), action_argv[0]);
 272                 r = -ENODEV;
 273                 break;
 274         case CRYPT_ACTIVE:
 275         case CRYPT_BUSY:
 276                 if (path)
 277                         log_std("%s is active%s.\n", action_argv[0],
 278                                 ci == CRYPT_BUSY ? " and is in use" : "");
 279                 else
 280                         log_std("%s/%s is active%s.\n", crypt_get_dir(), action_argv[0],
 281                                 ci == CRYPT_BUSY ? " and is in use" : "");
 282
 283                 r = crypt_init_by_name_and_header(&cd, action_argv[0], NULL);
 284                 if (r < 0 || !crypt_get_type(cd))
 285                         goto out;
 286
 287                 log_std("  type:        %s\n", crypt_get_type(cd));
 288
 289                 r = crypt_get_active_device(cd, action_argv[0], &cad);
 290                 if (r < 0)
 291                         goto out;
 292
 293                 log_std("  status:      %s\n",
 294                         cad.flags & CRYPT_ACTIVATE_CORRUPTED ? "corrupted" : "verified");
 295
 296                 r = crypt_get_verity_info(cd, &vp);
 297                 if (r < 0)
 298                         goto out;
 299
 300                 log_std("  hash type:   %u\n", vp.hash_type);
 301                 log_std("  data block:  %u\n", vp.data_block_size);
 302                 log_std("  hash block:  %u\n", vp.hash_block_size);
 303                 log_std("  hash name:   %s\n", vp.hash_name);
 304                 log_std("  salt:        ");
 305                 if (vp.salt_size)
 306                         for(i = 0; i < vp.salt_size; i++)
 307                                 log_std("%02hhx", (const char)vp.salt[i]);
 308                 else
 309                         log_std("-");
 310                 log_std("\n");
 311
 312                 log_std("  data device: %s\n", vp.data_device);
 313                 if (crypt_loop_device(vp.data_device)) {
 314                         backing_file = crypt_loop_backing_file(vp.data_device);
 315                         log_std("  data loop:   %s\n", backing_file);
 316                         free(backing_file);
 317                 }
 318                 log_std("  size:        %" PRIu64 " sectors\n", cad.size);
 319                 log_std("  mode:        %s\n", cad.flags & CRYPT_ACTIVATE_READONLY ?
 320                                            "readonly" : "read/write");
 321
 322                 log_std("  hash device: %s\n", vp.hash_device);
 323                 if (crypt_loop_device(vp.hash_device)) {
 324                         backing_file = crypt_loop_backing_file(vp.hash_device);
 325                         log_std("  hash loop:   %s\n", backing_file);
 326                         free(backing_file);
 327                 }
 328                 log_std("  hash offset: %" PRIu64 " sectors\n",
 329                         vp.hash_area_offset * vp.hash_block_size / 512);
 330         }
 331 out:
 332         crypt_free(cd);
 333         if (r == -ENOTSUP)
 334                 r = 0;
 335         return r;
 336 }
 337
 338 static int action_dump(int arg)
 339 {
 340         struct crypt_device *cd = NULL;
 341         struct crypt_params_verity params = {};
 342         int r;
 343
 344         if ((r = crypt_init(&cd, action_argv[0])))
 345                 return r;
 346
 347         params.hash_area_offset = hash_start;
 348         r = crypt_load(cd, CRYPT_VERITY, &params);
 349         if (!r)
 350                 crypt_dump(cd);
 351         crypt_free(cd);
 352         return r;
 353 }
 354
 355 static __attribute__ ((noreturn)) void usage(poptContext popt_context,
 356                                              int exitcode, const char *error,
 357                                              const char *more)
 358 {
 359         poptPrintUsage(popt_context, stderr, 0);
 360         if (error)
 361                 log_err("%s: %s\n", more, error);
 362         poptFreeContext(popt_context);
 363         exit(exitcode);
 364 }
 365
 366 static void _dbg_version_and_cmd(int argc, const char **argv)
 367 {
 368         int i;
 369
 370         log_std("# %s %s processing \"", PACKAGE_VERITY, PACKAGE_VERSION);
 371         for (i = 0; i < argc; i++) {
 372                 if (i)
 373                         log_std(" ");
 374                 log_std("%s", argv[i]);
 375         }
 376         log_std("\"\n");
 377 }
 378
 379 static struct action_type {
 380         const char *type;
 381         int (*handler)(int);
 382         int required_action_argc;
 383         const char *arg_desc;
 384         const char *desc;
 385 } action_types[] = {
 386         { "format",     action_format, 2, N_("<data_device> <hash_device>"),N_("format device") },
 387         { "verify",     action_verify, 3, N_("<data_device> <hash_device> <root_hash>"),N_("verify device") },
 388         { "create",     action_create, 4, N_("<name> <data_device> <hash_device> <root_hash>"),N_("create active device") },
 389         { "remove",     action_remove, 1, N_("<name>"),N_("remove (deactivate) device") },
 390         { "status",     action_status, 1, N_("<name>"),N_("show active device status") },
 391         { "dump",       action_dump,   1, N_("<hash_device>"),N_("show on-disk information") },
 392         { NULL, NULL, 0, NULL, NULL }
 393 };
 394
 395 static void help(poptContext popt_context,
 396                  enum poptCallbackReason reason __attribute__((unused)),
 397                  struct poptOption *key,
 398                  const char *arg __attribute__((unused)),
 399                  void *data __attribute__((unused)))
 400 {
 401         struct action_type *action;
 402
 403         if (key->shortName == '?') {
 404                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 405                 poptPrintHelp(popt_context, stdout, 0);
 406                 log_std(_("\n"
 407                          "<action> is one of:\n"));
 408                 for(action = action_types; action->type; action++)
 409                         log_std("\t%s %s - %s\n", action->type, _(action->arg_desc), _(action->desc));
 410                 log_std(_("\n"
 411                          "<name> is the device to create under %s\n"
 412                          "<data_device> is the data device\n"
 413                          "<hash_device> is the device containing verification data\n"
 414                          "<root_hash> hash of the root node on <hash_device>\n"),
 415                         crypt_get_dir());
 416
 417                 log_std(_("\nDefault compiled-in dm-verity parameters:\n"
 418                          "\tHash: %s, Data block (bytes): %u, "
 419                          "Hash block (bytes): %u, Salt size: %u, Hash format: %u\n"),
 420                         DEFAULT_VERITY_HASH, DEFAULT_VERITY_DATA_BLOCK,
 421                         DEFAULT_VERITY_HASH_BLOCK, DEFAULT_VERITY_SALT_SIZE,
 422                         1);
 423                 exit(EXIT_SUCCESS);
 424         } else
 425                 usage(popt_context, EXIT_SUCCESS, NULL, NULL);
 426 }
 427
 428 static void show_status(int errcode)
 429 {
 430         char error[256], *error_;
 431
 432         if(!opt_verbose)
 433                 return;
 434
 435         if(!errcode) {
 436                 log_std(_("Command successful.\n"));
 437                 return;
 438         }
 439
 440         crypt_get_error(error, sizeof(error));
 441
 442         if (!error[0]) {
 443                 error_ = strerror_r(-errcode, error, sizeof(error));
 444                 if (error_ != error) {
 445                         strncpy(error, error_, sizeof(error));
 446                         error[sizeof(error) - 1] = '\0';
 447                 }
 448         }
 449
 450         log_err(_("Command failed with code %i"), -errcode);
 451         if (*error)
 452                 log_err(": %s\n", error);
 453         else
 454                 log_err(".\n");
 455 }
 456
 457 static int run_action(struct action_type *action)
 458 {
 459         int r;
 460
 461         log_dbg("Running command %s.", action->type);
 462
 463         r = action->handler(0);
 464
 465         show_status(r);
 466
 467         /* Translate exit code to simple codes */
 468         switch (r) {
 469         case 0:         r = EXIT_SUCCESS; break;
 470         case -EEXIST:
 471         case -EBUSY:    r = 5; break;
 472         case -ENOTBLK:
 473         case -ENODEV:   r = 4; break;
 474         case -ENOMEM:   r = 3; break;
 475         case -EPERM:    r = 2; break;
 476         case -EINVAL:
 477         case -ENOENT:
 478         case -ENOSYS:
 479         default:        r = EXIT_FAILURE;
 480         }
 481         return r;
 482 }
 483
 484 int main(int argc, const char **argv)
 485 {
 486         static char *popt_tmp;
 487         static struct poptOption popt_help_options[] = {
 488                 { NULL,    '\0', POPT_ARG_CALLBACK, help, 0, NULL,                         NULL },
 489                 { "help",  '?',  POPT_ARG_NONE,     NULL, 0, N_("Show this help message"), NULL },
 490                 { "usage", '\0', POPT_ARG_NONE,     NULL, 0, N_("Display brief usage"),    NULL },
 491                 POPT_TABLEEND
 492         };
 493         static struct poptOption popt_options[] = {
 494                 { NULL,              '\0', POPT_ARG_INCLUDE_TABLE, popt_help_options, 0, N_("Help options:"), NULL },
 495                 { "version",         '\0', POPT_ARG_NONE, &opt_version_mode, 0, N_("Print package version"), NULL },
 496                 { "verbose",         'v',  POPT_ARG_NONE, &opt_verbose,      0, N_("Shows more detailed error messages"), NULL },
 497                 { "debug",           '\0', POPT_ARG_NONE, &opt_debug,        0, N_("Show debug messages"), NULL },
 498                 { "no-superblock",   0,    POPT_ARG_VAL,  &use_superblock,   0, N_("Do not use verity superblock"), NULL },
 499                 { "format",          0,    POPT_ARG_INT,  &hash_type,        0, N_("Format type (1 - normal, 0 - original Chrome OS)"), N_("number") },
 500                 { "data-block-size", 0,    POPT_ARG_INT,  &data_block_size,  0, N_("Block size on the data device"), N_("bytes") },
 501                 { "hash-block-size", 0,    POPT_ARG_INT,  &hash_block_size,  0, N_("Block size on the hash device"), N_("bytes") },
 502                 { "data-blocks",     0,    POPT_ARG_STRING, &popt_tmp,       1, N_("The number of blocks in the data file"), N_("blocks") },
 503                 { "hash-start",      0,    POPT_ARG_STRING, &popt_tmp,       2, N_("Starting block on the hash device"), N_("512-byte sectors") },
 504                 { "hash",            'h',  POPT_ARG_STRING, &hash_algorithm, 0, N_("Hash algorithm"), N_("string") },
 505                 { "salt",            's',  POPT_ARG_STRING, &salt_string,    0, N_("Salt"), N_("hex string") },
 506                 { "uuid",            '\0', POPT_ARG_STRING, &opt_uuid,       0, N_("UUID for device to use."), NULL },
 507                 POPT_TABLEEND
 508         };
 509
 510         poptContext popt_context;
 511         struct action_type *action;
 512         const char *aname, *null_action_argv[] = {NULL};
 513         int r;
 514
 515         crypt_set_log_callback(NULL, _log, NULL);
 516
 517         setlocale(LC_ALL, "");
 518         bindtextdomain(PACKAGE, LOCALEDIR);
 519         textdomain(PACKAGE);
 520
 521         popt_context = poptGetContext("verity", argc, argv, popt_options, 0);
 522         poptSetOtherOptionHelp(popt_context,
 523                                N_("[OPTION...] <action> <action-specific>"));
 524
 525         while((r = poptGetNextOpt(popt_context)) > 0) {
 526                 unsigned long long ull_value;
 527                 char *endp;
 528
 529                 errno = 0;
 530                 ull_value = strtoull(popt_tmp, &endp, 0);
 531                 if (*endp || !*popt_tmp ||
 532                     (errno == ERANGE && ull_value == ULLONG_MAX) ||
 533                     (errno != 0 && ull_value == 0))
 534                         r = POPT_ERROR_BADNUMBER;
 535
 536                 switch(r) {
 537                         case 1:
 538                                 data_blocks = ull_value;
 539                                 break;
 540                         case 2:
 541                                 hash_start = ull_value * 512;
 542                                 break;
 543                 }
 544
 545                 if (r < 0)
 546                         break;
 547         }
 548
 549         if (r < -1)
 550                 usage(popt_context, EXIT_FAILURE, poptStrerror(r),
 551                       poptBadOption(popt_context, POPT_BADOPTION_NOALIAS));
 552
 553         if (opt_version_mode) {
 554                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 555                 poptFreeContext(popt_context);
 556                 exit(EXIT_SUCCESS);
 557         }
 558
 559         if (!(aname = poptGetArg(popt_context)))
 560                 usage(popt_context, EXIT_FAILURE, _("Argument <action> missing."),
 561                       poptGetInvocationName(popt_context));
 562         for(action = action_types; action->type; action++)
 563                 if (strcmp(action->type, aname) == 0)
 564                         break;
 565         if (!action->type)
 566                 usage(popt_context, EXIT_FAILURE, _("Unknown action."),
 567                       poptGetInvocationName(popt_context));
 568
 569         action_argc = 0;
 570         action_argv = poptGetArgs(popt_context);
 571         /* Make return values of poptGetArgs more consistent in case of remaining argc = 0 */
 572         if(!action_argv)
 573                 action_argv = null_action_argv;
 574
 575         /* Count args, somewhat unnice, change? */
 576         while(action_argv[action_argc] != NULL)
 577                 action_argc++;
 578
 579         if(action_argc < action->required_action_argc) {
 580                 char buf[128];
 581                 snprintf(buf, 128,_("%s: requires %s as arguments"), action->type, action->arg_desc);
 582                 usage(popt_context, EXIT_FAILURE, buf,
 583                       poptGetInvocationName(popt_context));
 584         }
 585
 586         if (opt_debug) {
 587                 opt_verbose = 1;
 588                 crypt_set_debug_level(-1);
 589                 _dbg_version_and_cmd(argc, argv);
 590         }
 591
 592         r = run_action(action);
 593         poptFreeContext(popt_context);
 594         return r;
 595 }