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