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 static size_t hex_to_bytes(const char *hex, char **result)
  54 {
  55         char buf[3] = "xx\0", *endp, *bytes;
  56         size_t i, len;
  57
  58         len = strlen(hex);
  59         if (len % 2)
  60                 return -EINVAL;
  61         len /= 2;
  62
  63         if (!(bytes = malloc(len)))
  64                 return -ENOMEM;
  65
  66         for (i = 0; i < len; i++) {
  67                 memcpy(buf, &hex[i * 2], 2);
  68                 bytes[i] = strtoul(buf, &endp, 16);
  69                 if (endp != &buf[2]) {
  70                         free(bytes);
  71                         return -EINVAL;
  72                 }
  73         }
  74         *result = bytes;
  75         return i;
  76 }
  77
  78 __attribute__((format(printf, 5, 6)))
  79 static void clogger(struct crypt_device *cd, int level, const char *file,
  80                    int line, const char *format, ...)
  81 {
  82         va_list argp;
  83         char *target = NULL;
  84
  85         va_start(argp, format);
  86
  87         if (vasprintf(&target, format, argp) > 0) {
  88                 if (level >= 0) {
  89                         crypt_log(cd, level, target);
  90 #ifdef CRYPT_DEBUG
  91                 } else if (opt_debug)
  92                         printf("# %s:%d %s\n", file ?: "?", line, target);
  93 #else
  94                 } else if (opt_debug)
  95                         printf("# %s\n", target);
  96 #endif
  97         }
  98
  99         va_end(argp);
 100         free(target);
 101 }
 102
 103 static void _log(int level, const char *msg, void *usrptr __attribute__((unused)))
 104 {
 105         switch(level) {
 106
 107         case CRYPT_LOG_NORMAL:
 108                 fputs(msg, stdout);
 109                 break;
 110         case CRYPT_LOG_VERBOSE:
 111                 if (opt_verbose)
 112                         fputs(msg, stdout);
 113                 break;
 114         case CRYPT_LOG_ERROR:
 115                 fputs(msg, stderr);
 116                 break;
 117         case CRYPT_LOG_DEBUG:
 118                 if (opt_debug)
 119                         printf("# %s\n", msg);
 120                 break;
 121         default:
 122                 fprintf(stderr, "Internal error on logging class for msg: %s", msg);
 123                 break;
 124         }
 125 }
 126
 127 static int _prepare_format(struct crypt_params_verity *params,
 128                            const char *data_device,
 129                            uint32_t flags)
 130 {
 131         char *salt = NULL;
 132         int len;
 133
 134         params->hash_name = hash_algorithm ?: DEFAULT_VERITY_HASH;
 135         params->data_device = data_device;
 136
 137         if (salt_string && !strcmp(salt_string, "-")) {
 138                 params->salt_size = 0;
 139                 params->salt = NULL;
 140         } else if (salt_string) {
 141                 len = hex_to_bytes(salt_string, &salt);
 142                 if (len < 0) {
 143                         log_err(_("Invalid salt string specified.\n"));
 144                         return -EINVAL;
 145                 }
 146                 params->salt_size = len;
 147                 params->salt = salt;
 148         } else {
 149                 params->salt_size = DEFAULT_VERITY_SALT_SIZE;
 150                 params->salt = NULL;
 151         }
 152
 153         params->data_block_size = data_block_size;
 154         params->hash_block_size = hash_block_size;
 155         params->data_size = data_blocks;
 156         params->hash_area_offset = hash_offset;
 157         params->hash_type = hash_type;
 158         params->flags = flags;
 159
 160         return 0;
 161 }
 162
 163 static int action_format(int arg)
 164 {
 165         struct crypt_device *cd = NULL;
 166         struct crypt_params_verity params = {};
 167         uint32_t flags = CRYPT_VERITY_CREATE_HASH;
 168         int r;
 169
 170         if ((r = crypt_init(&cd, action_argv[1])))
 171                 goto out;
 172
 173         if (!use_superblock)
 174                 flags |= CRYPT_VERITY_NO_HEADER;
 175
 176         r = _prepare_format(&params, action_argv[0], flags);
 177         if (r < 0)
 178                 goto out;
 179
 180         r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, opt_uuid, NULL, 0, &params);
 181         if (!r)
 182                 crypt_dump(cd);
 183 out:
 184         crypt_free(cd);
 185         free((char*)params.salt);
 186         return r;
 187 }
 188
 189 static int _activate(const char *dm_device,
 190                       const char *data_device,
 191                       const char *hash_device,
 192                       const char *root_hash,
 193                       uint32_t flags)
 194 {
 195         struct crypt_device *cd = NULL;
 196         struct crypt_params_verity params = {};
 197         uint32_t activate_flags = CRYPT_ACTIVATE_READONLY;
 198         char *root_hash_bytes = NULL;
 199         size_t hash_size;
 200         int r;
 201
 202         if ((r = crypt_init(&cd, hash_device)))
 203                 goto out;
 204
 205         if (use_superblock) {
 206                 params.flags = flags;
 207                 params.hash_area_offset = hash_offset;
 208                 r = crypt_load(cd, CRYPT_VERITY, &params);
 209         } else {
 210                 r = _prepare_format(&params, data_device, flags | CRYPT_VERITY_NO_HEADER);
 211                 if (r < 0)
 212                         goto out;
 213                 r = crypt_format(cd, CRYPT_VERITY, NULL, NULL, NULL, NULL, 0, &params);
 214         }
 215         if (r < 0)
 216                 goto out;
 217         r = crypt_set_data_device(cd, data_device);
 218         if (r < 0)
 219                 goto out;
 220
 221         hash_size = crypt_get_volume_key_size(cd);
 222         if (hex_to_bytes(root_hash, &root_hash_bytes) != hash_size) {
 223                 log_err(_("Invalid root hash string specified.\n"));
 224                 r = -EINVAL;
 225                 goto out;
 226         }
 227         r = crypt_activate_by_volume_key(cd, dm_device,
 228                                          root_hash_bytes,
 229                                          hash_size,
 230                                          activate_flags);
 231 out:
 232         crypt_free(cd);
 233         free(root_hash_bytes);
 234         free((char*)params.salt);
 235         return r;
 236 }
 237
 238 static int action_create(int arg)
 239 {
 240         return _activate(action_argv[0],
 241                          action_argv[1],
 242                          action_argv[2],
 243                          action_argv[3], 0);
 244 }
 245
 246 static int action_verify(int arg)
 247 {
 248         return _activate(NULL,
 249                          action_argv[0],
 250                          action_argv[1],
 251                          action_argv[2],
 252                          CRYPT_VERITY_CHECK_HASH);
 253 }
 254
 255 static int action_remove(int arg)
 256 {
 257         struct crypt_device *cd = NULL;
 258         int r;
 259
 260         r = crypt_init_by_name(&cd, action_argv[0]);
 261         if (r == 0)
 262                 r = crypt_deactivate(cd, action_argv[0]);
 263
 264         crypt_free(cd);
 265         return r;
 266 }
 267
 268 static int action_status(int arg)
 269 {
 270         crypt_status_info ci;
 271         struct crypt_active_device cad;
 272         struct crypt_params_verity vp = {};
 273         struct crypt_device *cd = NULL;
 274         struct stat st;
 275         char *backing_file;
 276         unsigned i, path = 0;
 277         int r = 0;
 278
 279         /* perhaps a path, not a dm device name */
 280         if (strchr(action_argv[0], '/') && !stat(action_argv[0], &st))
 281                 path = 1;
 282
 283         ci = crypt_status(NULL, action_argv[0]);
 284         switch (ci) {
 285         case CRYPT_INVALID:
 286                 r = -EINVAL;
 287                 break;
 288         case CRYPT_INACTIVE:
 289                 if (path)
 290                         log_std("%s is inactive.\n", action_argv[0]);
 291                 else
 292                         log_std("%s/%s is inactive.\n", crypt_get_dir(), action_argv[0]);
 293                 r = -ENODEV;
 294                 break;
 295         case CRYPT_ACTIVE:
 296         case CRYPT_BUSY:
 297                 if (path)
 298                         log_std("%s is active%s.\n", action_argv[0],
 299                                 ci == CRYPT_BUSY ? " and is in use" : "");
 300                 else
 301                         log_std("%s/%s is active%s.\n", crypt_get_dir(), action_argv[0],
 302                                 ci == CRYPT_BUSY ? " and is in use" : "");
 303
 304                 r = crypt_init_by_name_and_header(&cd, action_argv[0], NULL);
 305                 if (r < 0 || !crypt_get_type(cd))
 306                         goto out;
 307
 308                 log_std("  type:        %s\n", crypt_get_type(cd));
 309
 310                 r = crypt_get_active_device(cd, action_argv[0], &cad);
 311                 if (r < 0)
 312                         goto out;
 313
 314                 log_std("  status:      %s\n",
 315                         cad.flags & CRYPT_ACTIVATE_CORRUPTED ? "corrupted" : "verified");
 316
 317                 r = crypt_get_verity_info(cd, &vp);
 318                 if (r < 0)
 319                         goto out;
 320
 321                 log_std("  hash type:   %u\n", vp.hash_type);
 322                 log_std("  data block:  %u\n", vp.data_block_size);
 323                 log_std("  hash block:  %u\n", vp.hash_block_size);
 324                 log_std("  hash name:   %s\n", vp.hash_name);
 325                 log_std("  salt:        ");
 326                 if (vp.salt_size)
 327                         for(i = 0; i < vp.salt_size; i++)
 328                                 log_std("%02hhx", (const char)vp.salt[i]);
 329                 else
 330                         log_std("-");
 331                 log_std("\n");
 332
 333                 log_std("  data device: %s\n", vp.data_device);
 334                 if (crypt_loop_device(vp.data_device)) {
 335                         backing_file = crypt_loop_backing_file(vp.data_device);
 336                         log_std("  data loop:   %s\n", backing_file);
 337                         free(backing_file);
 338                 }
 339                 log_std("  size:        %" PRIu64 " sectors\n", cad.size);
 340                 log_std("  mode:        %s\n", cad.flags & CRYPT_ACTIVATE_READONLY ?
 341                                            "readonly" : "read/write");
 342
 343                 log_std("  hash device: %s\n", vp.hash_device);
 344                 if (crypt_loop_device(vp.hash_device)) {
 345                         backing_file = crypt_loop_backing_file(vp.hash_device);
 346                         log_std("  hash loop:   %s\n", backing_file);
 347                         free(backing_file);
 348                 }
 349                 log_std("  hash offset: %" PRIu64 " sectors\n",
 350                         vp.hash_area_offset * vp.hash_block_size / 512);
 351         }
 352 out:
 353         crypt_free(cd);
 354         if (r == -ENOTSUP)
 355                 r = 0;
 356         return r;
 357 }
 358
 359 static int action_dump(int arg)
 360 {
 361         struct crypt_device *cd = NULL;
 362         struct crypt_params_verity params = {};
 363         int r;
 364
 365         if ((r = crypt_init(&cd, action_argv[0])))
 366                 return r;
 367
 368         params.hash_area_offset = hash_offset;
 369         r = crypt_load(cd, CRYPT_VERITY, &params);
 370         if (!r)
 371                 crypt_dump(cd);
 372         crypt_free(cd);
 373         return r;
 374 }
 375
 376 static __attribute__ ((noreturn)) void usage(poptContext popt_context,
 377                                              int exitcode, const char *error,
 378                                              const char *more)
 379 {
 380         poptPrintUsage(popt_context, stderr, 0);
 381         if (error)
 382                 log_err("%s: %s\n", more, error);
 383         poptFreeContext(popt_context);
 384         exit(exitcode);
 385 }
 386
 387 static void _dbg_version_and_cmd(int argc, const char **argv)
 388 {
 389         int i;
 390
 391         log_std("# %s %s processing \"", PACKAGE_VERITY, PACKAGE_VERSION);
 392         for (i = 0; i < argc; i++) {
 393                 if (i)
 394                         log_std(" ");
 395                 log_std("%s", argv[i]);
 396         }
 397         log_std("\"\n");
 398 }
 399
 400 static struct action_type {
 401         const char *type;
 402         int (*handler)(int);
 403         int required_action_argc;
 404         const char *arg_desc;
 405         const char *desc;
 406 } action_types[] = {
 407         { "format",     action_format, 2, N_("<data_device> <hash_device>"),N_("format device") },
 408         { "verify",     action_verify, 3, N_("<data_device> <hash_device> <root_hash>"),N_("verify device") },
 409         { "create",     action_create, 4, N_("<name> <data_device> <hash_device> <root_hash>"),N_("create active device") },
 410         { "remove",     action_remove, 1, N_("<name>"),N_("remove (deactivate) device") },
 411         { "status",     action_status, 1, N_("<name>"),N_("show active device status") },
 412         { "dump",       action_dump,   1, N_("<hash_device>"),N_("show on-disk information") },
 413         { NULL, NULL, 0, NULL, NULL }
 414 };
 415
 416 static void help(poptContext popt_context,
 417                  enum poptCallbackReason reason __attribute__((unused)),
 418                  struct poptOption *key,
 419                  const char *arg __attribute__((unused)),
 420                  void *data __attribute__((unused)))
 421 {
 422         struct action_type *action;
 423
 424         if (key->shortName == '?') {
 425                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 426                 poptPrintHelp(popt_context, stdout, 0);
 427                 log_std(_("\n"
 428                          "<action> is one of:\n"));
 429                 for(action = action_types; action->type; action++)
 430                         log_std("\t%s %s - %s\n", action->type, _(action->arg_desc), _(action->desc));
 431                 log_std(_("\n"
 432                          "<name> is the device to create under %s\n"
 433                          "<data_device> is the data device\n"
 434                          "<hash_device> is the device containing verification data\n"
 435                          "<root_hash> hash of the root node on <hash_device>\n"),
 436                         crypt_get_dir());
 437
 438                 log_std(_("\nDefault compiled-in dm-verity parameters:\n"
 439                          "\tHash: %s, Data block (bytes): %u, "
 440                          "Hash block (bytes): %u, Salt size: %u, Hash format: %u\n"),
 441                         DEFAULT_VERITY_HASH, DEFAULT_VERITY_DATA_BLOCK,
 442                         DEFAULT_VERITY_HASH_BLOCK, DEFAULT_VERITY_SALT_SIZE,
 443                         1);
 444                 exit(EXIT_SUCCESS);
 445         } else
 446                 usage(popt_context, EXIT_SUCCESS, NULL, NULL);
 447 }
 448
 449 static void show_status(int errcode)
 450 {
 451         char error[256], *error_;
 452
 453         if(!opt_verbose)
 454                 return;
 455
 456         if(!errcode) {
 457                 log_std(_("Command successful.\n"));
 458                 return;
 459         }
 460
 461         crypt_get_error(error, sizeof(error));
 462
 463         if (!error[0]) {
 464                 error_ = strerror_r(-errcode, error, sizeof(error));
 465                 if (error_ != error) {
 466                         strncpy(error, error_, sizeof(error));
 467                         error[sizeof(error) - 1] = '\0';
 468                 }
 469         }
 470
 471         log_err(_("Command failed with code %i"), -errcode);
 472         if (*error)
 473                 log_err(": %s\n", error);
 474         else
 475                 log_err(".\n");
 476 }
 477
 478 static int run_action(struct action_type *action)
 479 {
 480         int r;
 481
 482         log_dbg("Running command %s.", action->type);
 483
 484         r = action->handler(0);
 485
 486         show_status(r);
 487
 488         /* Translate exit code to simple codes */
 489         switch (r) {
 490         case 0:         r = EXIT_SUCCESS; break;
 491         case -EEXIST:
 492         case -EBUSY:    r = 5; break;
 493         case -ENOTBLK:
 494         case -ENODEV:   r = 4; break;
 495         case -ENOMEM:   r = 3; break;
 496         case -EPERM:    r = 2; break;
 497         case -EINVAL:
 498         case -ENOENT:
 499         case -ENOSYS:
 500         default:        r = EXIT_FAILURE;
 501         }
 502         return r;
 503 }
 504
 505 int main(int argc, const char **argv)
 506 {
 507         static char *popt_tmp;
 508         static const char *null_action_argv[] = {NULL};
 509         static struct poptOption popt_help_options[] = {
 510                 { NULL,    '\0', POPT_ARG_CALLBACK, help, 0, NULL,                         NULL },
 511                 { "help",  '?',  POPT_ARG_NONE,     NULL, 0, N_("Show this help message"), NULL },
 512                 { "usage", '\0', POPT_ARG_NONE,     NULL, 0, N_("Display brief usage"),    NULL },
 513                 POPT_TABLEEND
 514         };
 515         static struct poptOption popt_options[] = {
 516                 { NULL,              '\0', POPT_ARG_INCLUDE_TABLE, popt_help_options, 0, N_("Help options:"), NULL },
 517                 { "version",         '\0', POPT_ARG_NONE, &opt_version_mode, 0, N_("Print package version"), NULL },
 518                 { "verbose",         'v',  POPT_ARG_NONE, &opt_verbose,      0, N_("Shows more detailed error messages"), NULL },
 519                 { "debug",           '\0', POPT_ARG_NONE, &opt_debug,        0, N_("Show debug messages"), NULL },
 520                 { "no-superblock",   0,    POPT_ARG_VAL,  &use_superblock,   0, N_("Do not use verity superblock"), NULL },
 521                 { "format",          0,    POPT_ARG_INT,  &hash_type,        0, N_("Format type (1 - normal, 0 - original Chrome OS)"), N_("number") },
 522                 { "data-block-size", 0,    POPT_ARG_INT,  &data_block_size,  0, N_("Block size on the data device"), N_("bytes") },
 523                 { "hash-block-size", 0,    POPT_ARG_INT,  &hash_block_size,  0, N_("Block size on the hash device"), N_("bytes") },
 524                 { "data-blocks",     0,    POPT_ARG_STRING, &popt_tmp,       1, N_("The number of blocks in the data file"), N_("blocks") },
 525                 { "hash-offset",     0,    POPT_ARG_STRING, &popt_tmp,       2, N_("Starting offset on the hash device"), N_("bytes") },
 526                 { "hash",            'h',  POPT_ARG_STRING, &hash_algorithm, 0, N_("Hash algorithm"), N_("string") },
 527                 { "salt",            's',  POPT_ARG_STRING, &salt_string,    0, N_("Salt"), N_("hex string") },
 528                 { "uuid",            '\0', POPT_ARG_STRING, &opt_uuid,       0, N_("UUID for device to use."), NULL },
 529                 POPT_TABLEEND
 530         };
 531
 532         poptContext popt_context;
 533         struct action_type *action;
 534         const char *aname;
 535         int r;
 536
 537         crypt_set_log_callback(NULL, _log, NULL);
 538
 539         setlocale(LC_ALL, "");
 540         bindtextdomain(PACKAGE, LOCALEDIR);
 541         textdomain(PACKAGE);
 542
 543         popt_context = poptGetContext("verity", argc, argv, popt_options, 0);
 544         poptSetOtherOptionHelp(popt_context,
 545                                N_("[OPTION...] <action> <action-specific>"));
 546
 547         while((r = poptGetNextOpt(popt_context)) > 0) {
 548                 unsigned long long ull_value;
 549                 char *endp;
 550
 551                 errno = 0;
 552                 ull_value = strtoull(popt_tmp, &endp, 10);
 553                 if (*endp || !*popt_tmp || !isdigit(*popt_tmp) ||
 554                     (errno == ERANGE && ull_value == ULLONG_MAX) ||
 555                     (errno != 0 && ull_value == 0))
 556                         r = POPT_ERROR_BADNUMBER;
 557
 558                 switch(r) {
 559                         case 1:
 560                                 data_blocks = ull_value;
 561                                 break;
 562                         case 2:
 563                                 hash_offset = ull_value;
 564                                 break;
 565                 }
 566
 567                 if (r < 0)
 568                         break;
 569         }
 570
 571         if (r < -1)
 572                 usage(popt_context, EXIT_FAILURE, poptStrerror(r),
 573                       poptBadOption(popt_context, POPT_BADOPTION_NOALIAS));
 574
 575         if (opt_version_mode) {
 576                 log_std("%s %s\n", PACKAGE_VERITY, PACKAGE_VERSION);
 577                 poptFreeContext(popt_context);
 578                 exit(EXIT_SUCCESS);
 579         }
 580
 581         if (!(aname = poptGetArg(popt_context)))
 582                 usage(popt_context, EXIT_FAILURE, _("Argument <action> missing."),
 583                       poptGetInvocationName(popt_context));
 584         for(action = action_types; action->type; action++)
 585                 if (strcmp(action->type, aname) == 0)
 586                         break;
 587         if (!action->type)
 588                 usage(popt_context, EXIT_FAILURE, _("Unknown action."),
 589                       poptGetInvocationName(popt_context));
 590
 591         action_argc = 0;
 592         action_argv = poptGetArgs(popt_context);
 593         /* Make return values of poptGetArgs more consistent in case of remaining argc = 0 */
 594         if(!action_argv)
 595                 action_argv = null_action_argv;
 596
 597         /* Count args, somewhat unnice, change? */
 598         while(action_argv[action_argc] != NULL)
 599                 action_argc++;
 600
 601         if(action_argc < action->required_action_argc) {
 602                 char buf[128];
 603                 snprintf(buf, 128,_("%s: requires %s as arguments"), action->type, action->arg_desc);
 604                 usage(popt_context, EXIT_FAILURE, buf,
 605                       poptGetInvocationName(popt_context));
 606         }
 607
 608         if (data_block_size < 0 || hash_block_size < 0 || hash_type < 0) {
 609                 usage(popt_context, EXIT_FAILURE,
 610                       _("Negative number for option not permitted."),
 611                       poptGetInvocationName(popt_context));
 612         }
 613
 614         if (opt_debug) {
 615                 opt_verbose = 1;
 616                 crypt_set_debug_level(-1);
 617                 _dbg_version_and_cmd(argc, argv);
 618         }
 619
 620         r = run_action(action);
 621         poptFreeContext(popt_context);
 622         return r;
 623 }