lib/libzfs/libzfs_crypto.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * This file and its contents are supplied under the terms of the
   5  * Common Development and Distribution License ("CDDL"), version 1.0.
   6  * You may only use this file in accordance with the terms of version
   7  * 1.0 of the CDDL.
   8  *
   9  * A full copy of the text of the CDDL should have accompanied this
  10  * source.  A copy of the CDDL is also available via the Internet at
  11  * http://www.illumos.org/license/CDDL.
  12  *
  13  * CDDL HEADER END
  14  */
  15
  16 /*
  17  * Copyright (c) 2017, Datto, Inc. All rights reserved.
  18  * Copyright 2020 Joyent, Inc.
  19  */
  20
  21 #include <sys/zfs_context.h>
  22 #include <sys/fs/zfs.h>
  23 #include <sys/dsl_crypt.h>
  24 #include <libintl.h>
  25 #include <termios.h>
  26 #include <signal.h>
  27 #include <errno.h>
  28 #include <openssl/evp.h>
  29 #include <libzfs.h>
  30 #include "libzfs_impl.h"
  31 #include "zfeature_common.h"
  32
  33 /*
  34  * User keys are used to decrypt the master encryption keys of a dataset. This
  35  * indirection allows a user to change his / her access key without having to
  36  * re-encrypt the entire dataset. User keys can be provided in one of several
  37  * ways. Raw keys are simply given to the kernel as is. Similarly, hex keys
  38  * are converted to binary and passed into the kernel. Password based keys are
  39  * a bit more complicated. Passwords alone do not provide suitable entropy for
  40  * encryption and may be too short or too long to be used. In order to derive
  41  * a more appropriate key we use a PBKDF2 function. This function is designed
  42  * to take a (relatively) long time to calculate in order to discourage
  43  * attackers from guessing from a list of common passwords. PBKDF2 requires
  44  * 2 additional parameters. The first is the number of iterations to run, which
  45  * will ultimately determine how long it takes to derive the resulting key from
  46  * the password. The second parameter is a salt that is randomly generated for
  47  * each dataset. The salt is used to "tweak" PBKDF2 such that a group of
  48  * attackers cannot reasonably generate a table of commonly known passwords to
  49  * their output keys and expect it work for all past and future PBKDF2 users.
  50  * We store the salt as a hidden property of the dataset (although it is
  51  * technically ok if the salt is known to the attacker).
  52  */
  53
  54 typedef enum key_locator {
  55         KEY_LOCATOR_NONE,
  56         KEY_LOCATOR_PROMPT,
  57         KEY_LOCATOR_URI
  58 } key_locator_t;
  59
  60 #define MIN_PASSPHRASE_LEN 8
  61 #define MAX_PASSPHRASE_LEN 512
  62 #define MAX_KEY_PROMPT_ATTEMPTS 3
  63
  64 static int caught_interrupt;
  65
  66 static int get_key_material_file(libzfs_handle_t *, const char *, const char *,
  67     zfs_keyformat_t, boolean_t, uint8_t **, size_t *);
  68
  69 static zfs_uri_handler_t uri_handlers[] = {
  70         { "file", get_key_material_file },
  71         { NULL, NULL }
  72 };
  73
  74 static int
  75 pkcs11_get_urandom(uint8_t *buf, size_t bytes)
  76 {
  77         int rand;
  78         ssize_t bytes_read = 0;
  79
  80         rand = open("/dev/urandom", O_RDONLY);
  81
  82         if (rand < 0)
  83                 return (rand);
  84
  85         while (bytes_read < bytes) {
  86                 ssize_t rc = read(rand, buf + bytes_read, bytes - bytes_read);
  87                 if (rc < 0)
  88                         break;
  89                 bytes_read += rc;
  90         }
  91
  92         (void) close(rand);
  93
  94         return (bytes_read);
  95 }
  96
  97 static int
  98 zfs_prop_parse_keylocation(libzfs_handle_t *restrict hdl, const char *str,
  99     zfs_keylocation_t *restrict locp, char **restrict schemep)
 100 {
 101         *locp = ZFS_KEYLOCATION_NONE;
 102         *schemep = NULL;
 103
 104         if (strcmp("prompt", str) == 0) {
 105                 *locp = ZFS_KEYLOCATION_PROMPT;
 106                 return (0);
 107         }
 108
 109         regmatch_t pmatch[2];
 110
 111         if (regexec(&hdl->libzfs_urire, str, ARRAY_SIZE(pmatch),
 112             pmatch, 0) == 0) {
 113                 size_t scheme_len;
 114
 115                 if (pmatch[1].rm_so == -1) {
 116                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 117                             "Invalid URI"));
 118                         return (EINVAL);
 119                 }
 120
 121                 scheme_len = pmatch[1].rm_eo - pmatch[1].rm_so;
 122
 123                 *schemep = calloc(1, scheme_len + 1);
 124                 if (*schemep == NULL) {
 125                         int ret = errno;
 126
 127                         errno = 0;
 128                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 129                             "Invalid URI"));
 130                         return (ret);
 131                 }
 132
 133                 (void) memcpy(*schemep, str + pmatch[1].rm_so, scheme_len);
 134                 *locp = ZFS_KEYLOCATION_URI;
 135                 return (0);
 136         }
 137
 138         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "Invalid keylocation"));
 139         return (EINVAL);
 140 }
 141
 142 static int
 143 hex_key_to_raw(char *hex, int hexlen, uint8_t *out)
 144 {
 145         int ret, i;
 146         unsigned int c;
 147
 148         for (i = 0; i < hexlen; i += 2) {
 149                 if (!isxdigit(hex[i]) || !isxdigit(hex[i + 1])) {
 150                         ret = EINVAL;
 151                         goto error;
 152                 }
 153
 154                 ret = sscanf(&hex[i], "%02x", &c);
 155                 if (ret != 1) {
 156                         ret = EINVAL;
 157                         goto error;
 158                 }
 159
 160                 out[i / 2] = c;
 161         }
 162
 163         return (0);
 164
 165 error:
 166         return (ret);
 167 }
 168
 169
 170 static void
 171 catch_signal(int sig)
 172 {
 173         caught_interrupt = sig;
 174 }
 175
 176 static const char *
 177 get_format_prompt_string(zfs_keyformat_t format)
 178 {
 179         switch (format) {
 180         case ZFS_KEYFORMAT_RAW:
 181                 return ("raw key");
 182         case ZFS_KEYFORMAT_HEX:
 183                 return ("hex key");
 184         case ZFS_KEYFORMAT_PASSPHRASE:
 185                 return ("passphrase");
 186         default:
 187                 /* shouldn't happen */
 188                 return (NULL);
 189         }
 190 }
 191
 192 /* do basic validation of the key material */
 193 static int
 194 validate_key(libzfs_handle_t *hdl, zfs_keyformat_t keyformat,
 195     const char *key, size_t keylen)
 196 {
 197         switch (keyformat) {
 198         case ZFS_KEYFORMAT_RAW:
 199                 /* verify the key length is correct */
 200                 if (keylen < WRAPPING_KEY_LEN) {
 201                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 202                             "Raw key too short (expected %u)."),
 203                             WRAPPING_KEY_LEN);
 204                         return (EINVAL);
 205                 }
 206
 207                 if (keylen > WRAPPING_KEY_LEN) {
 208                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 209                             "Raw key too long (expected %u)."),
 210                             WRAPPING_KEY_LEN);
 211                         return (EINVAL);
 212                 }
 213                 break;
 214         case ZFS_KEYFORMAT_HEX:
 215                 /* verify the key length is correct */
 216                 if (keylen < WRAPPING_KEY_LEN * 2) {
 217                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 218                             "Hex key too short (expected %u)."),
 219                             WRAPPING_KEY_LEN * 2);
 220                         return (EINVAL);
 221                 }
 222
 223                 if (keylen > WRAPPING_KEY_LEN * 2) {
 224                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 225                             "Hex key too long (expected %u)."),
 226                             WRAPPING_KEY_LEN * 2);
 227                         return (EINVAL);
 228                 }
 229
 230                 /* check for invalid hex digits */
 231                 for (size_t i = 0; i < WRAPPING_KEY_LEN * 2; i++) {
 232                         if (!isxdigit(key[i])) {
 233                                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 234                                     "Invalid hex character detected."));
 235                                 return (EINVAL);
 236                         }
 237                 }
 238                 break;
 239         case ZFS_KEYFORMAT_PASSPHRASE:
 240                 /* verify the length is within bounds */
 241                 if (keylen > MAX_PASSPHRASE_LEN) {
 242                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 243                             "Passphrase too long (max %u)."),
 244                             MAX_PASSPHRASE_LEN);
 245                         return (EINVAL);
 246                 }
 247
 248                 if (keylen < MIN_PASSPHRASE_LEN) {
 249                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 250                             "Passphrase too short (min %u)."),
 251                             MIN_PASSPHRASE_LEN);
 252                         return (EINVAL);
 253                 }
 254                 break;
 255         default:
 256                 /* can't happen, checked above */
 257                 break;
 258         }
 259
 260         return (0);
 261 }
 262
 263 static int
 264 libzfs_getpassphrase(zfs_keyformat_t keyformat, boolean_t is_reenter,
 265     boolean_t new_key, const char *fsname,
 266     char **restrict res, size_t *restrict reslen)
 267 {
 268         FILE *f = stdin;
 269         size_t buflen = 0;
 270         ssize_t bytes;
 271         int ret = 0;
 272         struct termios old_term, new_term;
 273         struct sigaction act, osigint, osigtstp;
 274
 275         *res = NULL;
 276         *reslen = 0;
 277
 278         /*
 279          * handle SIGINT and ignore SIGSTP. This is necessary to
 280          * restore the state of the terminal.
 281          */
 282         caught_interrupt = 0;
 283         act.sa_flags = 0;
 284         (void) sigemptyset(&act.sa_mask);
 285         act.sa_handler = catch_signal;
 286
 287         (void) sigaction(SIGINT, &act, &osigint);
 288         act.sa_handler = SIG_IGN;
 289         (void) sigaction(SIGTSTP, &act, &osigtstp);
 290
 291         (void) printf("%s %s%s",
 292             is_reenter ? "Re-enter" : "Enter",
 293             new_key ? "new " : "",
 294             get_format_prompt_string(keyformat));
 295         if (fsname != NULL)
 296                 (void) printf(" for '%s'", fsname);
 297         (void) fputc(':', stdout);
 298         (void) fflush(stdout);
 299
 300         /* disable the terminal echo for key input */
 301         (void) tcgetattr(fileno(f), &old_term);
 302
 303         new_term = old_term;
 304         new_term.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL);
 305
 306         ret = tcsetattr(fileno(f), TCSAFLUSH, &new_term);
 307         if (ret != 0) {
 308                 ret = errno;
 309                 errno = 0;
 310                 goto out;
 311         }
 312
 313         bytes = getline(res, &buflen, f);
 314         if (bytes < 0) {
 315                 ret = errno;
 316                 errno = 0;
 317                 goto out;
 318         }
 319
 320         /* trim the ending newline if it exists */
 321         if (bytes > 0 && (*res)[bytes - 1] == '\n') {
 322                 (*res)[bytes - 1] = '\0';
 323                 bytes--;
 324         }
 325
 326         *reslen = bytes;
 327
 328 out:
 329         /* reset the terminal */
 330         (void) tcsetattr(fileno(f), TCSAFLUSH, &old_term);
 331         (void) sigaction(SIGINT, &osigint, NULL);
 332         (void) sigaction(SIGTSTP, &osigtstp, NULL);
 333
 334         /* if we caught a signal, re-throw it now */
 335         if (caught_interrupt != 0)
 336                 (void) kill(getpid(), caught_interrupt);
 337
 338         /* print the newline that was not echo'd */
 339         (void) printf("\n");
 340
 341         return (ret);
 342 }
 343
 344 static int
 345 get_key_interactive(libzfs_handle_t *restrict hdl, const char *fsname,
 346     zfs_keyformat_t keyformat, boolean_t confirm_key, boolean_t newkey,
 347     uint8_t **restrict outbuf, size_t *restrict len_out)
 348 {
 349         char *buf = NULL, *buf2 = NULL;
 350         size_t buflen = 0, buf2len = 0;
 351         int ret = 0;
 352
 353         ASSERT(isatty(fileno(stdin)));
 354
 355         /* raw keys cannot be entered on the terminal */
 356         if (keyformat == ZFS_KEYFORMAT_RAW) {
 357                 ret = EINVAL;
 358                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 359                     "Cannot enter raw keys on the terminal"));
 360                 goto out;
 361         }
 362
 363         /* prompt for the key */
 364         if ((ret = libzfs_getpassphrase(keyformat, B_FALSE, newkey, fsname,
 365             &buf, &buflen)) != 0) {
 366                 free(buf);
 367                 buf = NULL;
 368                 buflen = 0;
 369                 goto out;
 370         }
 371
 372         if (!confirm_key)
 373                 goto out;
 374
 375         if ((ret = validate_key(hdl, keyformat, buf, buflen)) != 0) {
 376                 free(buf);
 377                 return (ret);
 378         }
 379
 380         ret = libzfs_getpassphrase(keyformat, B_TRUE, newkey, fsname, &buf2,
 381             &buf2len);
 382         if (ret != 0) {
 383                 free(buf);
 384                 free(buf2);
 385                 buf = buf2 = NULL;
 386                 buflen = buf2len = 0;
 387                 goto out;
 388         }
 389
 390         if (buflen != buf2len || strcmp(buf, buf2) != 0) {
 391                 free(buf);
 392                 buf = NULL;
 393                 buflen = 0;
 394
 395                 ret = EINVAL;
 396                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 397                     "Provided keys do not match."));
 398         }
 399
 400         free(buf2);
 401
 402 out:
 403         *outbuf = (uint8_t *)buf;
 404         *len_out = buflen;
 405         return (ret);
 406 }
 407
 408 static int
 409 get_key_material_raw(FILE *fd, zfs_keyformat_t keyformat,
 410     uint8_t **buf, size_t *len_out)
 411 {
 412         int ret = 0;
 413         size_t buflen = 0;
 414
 415         *len_out = 0;
 416
 417         /* read the key material */
 418         if (keyformat != ZFS_KEYFORMAT_RAW) {
 419                 ssize_t bytes;
 420
 421                 bytes = getline((char **)buf, &buflen, fd);
 422                 if (bytes < 0) {
 423                         ret = errno;
 424                         errno = 0;
 425                         goto out;
 426                 }
 427
 428                 /* trim the ending newline if it exists */
 429                 if (bytes > 0 && (*buf)[bytes - 1] == '\n') {
 430                         (*buf)[bytes - 1] = '\0';
 431                         bytes--;
 432                 }
 433
 434                 *len_out = bytes;
 435         } else {
 436                 size_t n;
 437
 438                 /*
 439                  * Raw keys may have newline characters in them and so can't
 440                  * use getline(). Here we attempt to read 33 bytes so that we
 441                  * can properly check the key length (the file should only have
 442                  * 32 bytes).
 443                  */
 444                 *buf = malloc((WRAPPING_KEY_LEN + 1) * sizeof (uint8_t));
 445                 if (*buf == NULL) {
 446                         ret = ENOMEM;
 447                         goto out;
 448                 }
 449
 450                 n = fread(*buf, 1, WRAPPING_KEY_LEN + 1, fd);
 451                 if (n == 0 || ferror(fd)) {
 452                         /* size errors are handled by the calling function */
 453                         free(*buf);
 454                         *buf = NULL;
 455                         ret = errno;
 456                         errno = 0;
 457                         goto out;
 458                 }
 459
 460                 *len_out = n;
 461         }
 462 out:
 463         return (ret);
 464 }
 465
 466 static int
 467 get_key_material_file(libzfs_handle_t *hdl, const char *uri,
 468     const char *fsname, zfs_keyformat_t keyformat, boolean_t newkey,
 469     uint8_t **restrict buf, size_t *restrict len_out)
 470 {
 471         FILE *f = NULL;
 472         int ret = 0;
 473
 474         if (strlen(uri) < 7)
 475                 return (EINVAL);
 476
 477         if ((f = fopen(uri + 7, "r")) == NULL) {
 478                 ret = errno;
 479                 errno = 0;
 480                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 481                     "Failed to open key material file"));
 482                 return (ret);
 483         }
 484
 485         ret = get_key_material_raw(f, keyformat, buf, len_out);
 486
 487         (void) fclose(f);
 488
 489         return (ret);
 490 }
 491
 492 /*
 493  * Attempts to fetch key material, no matter where it might live. The key
 494  * material is allocated and returned in km_out. *can_retry_out will be set
 495  * to B_TRUE if the user is providing the key material interactively, allowing
 496  * for re-entry attempts.
 497  */
 498 static int
 499 get_key_material(libzfs_handle_t *hdl, boolean_t do_verify, boolean_t newkey,
 500     zfs_keyformat_t keyformat, char *keylocation, const char *fsname,
 501     uint8_t **km_out, size_t *kmlen_out, boolean_t *can_retry_out)
 502 {
 503         int ret;
 504         zfs_keylocation_t keyloc = ZFS_KEYLOCATION_NONE;
 505         uint8_t *km = NULL;
 506         size_t kmlen = 0;
 507         char *uri_scheme = NULL;
 508         zfs_uri_handler_t *handler = NULL;
 509         boolean_t can_retry = B_FALSE;
 510
 511         /* verify and parse the keylocation */
 512         ret = zfs_prop_parse_keylocation(hdl, keylocation, &keyloc,
 513             &uri_scheme);
 514         if (ret != 0)
 515                 goto error;
 516
 517         /* open the appropriate file descriptor */
 518         switch (keyloc) {
 519         case ZFS_KEYLOCATION_PROMPT:
 520                 if (isatty(fileno(stdin))) {
 521                         can_retry = B_TRUE;
 522                         ret = get_key_interactive(hdl, fsname, keyformat,
 523                             do_verify, newkey, &km, &kmlen);
 524                 } else {
 525                         /* fetch the key material into the buffer */
 526                         ret = get_key_material_raw(stdin, keyformat, &km,
 527                             &kmlen);
 528                 }
 529
 530                 if (ret != 0)
 531                         goto error;
 532
 533                 break;
 534         case ZFS_KEYLOCATION_URI:
 535                 for (handler = uri_handlers; handler->zuh_scheme != NULL;
 536                     handler++) {
 537                         if (strcmp(handler->zuh_scheme, uri_scheme) != 0)
 538                                 continue;
 539
 540                         if ((ret = handler->zuh_handler(hdl, keylocation,
 541                             fsname, keyformat, newkey, &km, &kmlen)) != 0)
 542                                 goto error;
 543
 544                         break;
 545                 }
 546
 547                 ret = ENOTSUP;
 548                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 549                     "URI scheme is not supported"));
 550
 551                 break;
 552         default:
 553                 ret = EINVAL;
 554                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 555                     "Invalid keylocation."));
 556                 goto error;
 557         }
 558
 559         if ((ret = validate_key(hdl, keyformat, (const char *)km, kmlen)) != 0)
 560                 goto error;
 561
 562         *km_out = km;
 563         *kmlen_out = kmlen;
 564         if (can_retry_out != NULL)
 565                 *can_retry_out = can_retry;
 566
 567         free(uri_scheme);
 568         return (0);
 569
 570 error:
 571         free(km);
 572
 573         *km_out = NULL;
 574         *kmlen_out = 0;
 575
 576         if (can_retry_out != NULL)
 577                 *can_retry_out = can_retry;
 578
 579         free(uri_scheme);
 580         return (ret);
 581 }
 582
 583 static int
 584 derive_key(libzfs_handle_t *hdl, zfs_keyformat_t format, uint64_t iters,
 585     uint8_t *key_material, size_t key_material_len, uint64_t salt,
 586     uint8_t **key_out)
 587 {
 588         int ret;
 589         uint8_t *key;
 590
 591         *key_out = NULL;
 592
 593         key = zfs_alloc(hdl, WRAPPING_KEY_LEN);
 594         if (!key)
 595                 return (ENOMEM);
 596
 597         switch (format) {
 598         case ZFS_KEYFORMAT_RAW:
 599                 bcopy(key_material, key, WRAPPING_KEY_LEN);
 600                 break;
 601         case ZFS_KEYFORMAT_HEX:
 602                 ret = hex_key_to_raw((char *)key_material,
 603                     WRAPPING_KEY_LEN * 2, key);
 604                 if (ret != 0) {
 605                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 606                             "Invalid hex key provided."));
 607                         goto error;
 608                 }
 609                 break;
 610         case ZFS_KEYFORMAT_PASSPHRASE:
 611                 salt = LE_64(salt);
 612
 613                 ret = PKCS5_PBKDF2_HMAC_SHA1((char *)key_material,
 614                     strlen((char *)key_material), ((uint8_t *)&salt),
 615                     sizeof (uint64_t), iters, WRAPPING_KEY_LEN, key);
 616                 if (ret != 1) {
 617                         ret = EIO;
 618                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 619                             "Failed to generate key from passphrase."));
 620                         goto error;
 621                 }
 622                 break;
 623         default:
 624                 ret = EINVAL;
 625                 goto error;
 626         }
 627
 628         *key_out = key;
 629         return (0);
 630
 631 error:
 632         free(key);
 633
 634         *key_out = NULL;
 635         return (ret);
 636 }
 637
 638 static boolean_t
 639 encryption_feature_is_enabled(zpool_handle_t *zph)
 640 {
 641         nvlist_t *features;
 642         uint64_t feat_refcount;
 643
 644         /* check that features can be enabled */
 645         if (zpool_get_prop_int(zph, ZPOOL_PROP_VERSION, NULL)
 646             < SPA_VERSION_FEATURES)
 647                 return (B_FALSE);
 648
 649         /* check for crypto feature */
 650         features = zpool_get_features(zph);
 651         if (!features || nvlist_lookup_uint64(features,
 652             spa_feature_table[SPA_FEATURE_ENCRYPTION].fi_guid,
 653             &feat_refcount) != 0)
 654                 return (B_FALSE);
 655
 656         return (B_TRUE);
 657 }
 658
 659 static int
 660 populate_create_encryption_params_nvlists(libzfs_handle_t *hdl,
 661     zfs_handle_t *zhp, boolean_t newkey, zfs_keyformat_t keyformat,
 662     char *keylocation, nvlist_t *props, uint8_t **wkeydata, uint_t *wkeylen)
 663 {
 664         int ret;
 665         uint64_t iters = 0, salt = 0;
 666         uint8_t *key_material = NULL;
 667         size_t key_material_len = 0;
 668         uint8_t *key_data = NULL;
 669         const char *fsname = (zhp) ? zfs_get_name(zhp) : NULL;
 670
 671         /* get key material from keyformat and keylocation */
 672         ret = get_key_material(hdl, B_TRUE, newkey, keyformat, keylocation,
 673             fsname, &key_material, &key_material_len, NULL);
 674         if (ret != 0)
 675                 goto error;
 676
 677         /* passphrase formats require a salt and pbkdf2 iters property */
 678         if (keyformat == ZFS_KEYFORMAT_PASSPHRASE) {
 679                 /* always generate a new salt */
 680                 ret = pkcs11_get_urandom((uint8_t *)&salt, sizeof (uint64_t));
 681                 if (ret != sizeof (uint64_t)) {
 682                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 683                             "Failed to generate salt."));
 684                         goto error;
 685                 }
 686
 687                 ret = nvlist_add_uint64(props,
 688                     zfs_prop_to_name(ZFS_PROP_PBKDF2_SALT), salt);
 689                 if (ret != 0) {
 690                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 691                             "Failed to add salt to properties."));
 692                         goto error;
 693                 }
 694
 695                 /*
 696                  * If not otherwise specified, use the default number of
 697                  * pbkdf2 iterations. If specified, we have already checked
 698                  * that the given value is greater than MIN_PBKDF2_ITERATIONS
 699                  * during zfs_valid_proplist().
 700                  */
 701                 ret = nvlist_lookup_uint64(props,
 702                     zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), &iters);
 703                 if (ret == ENOENT) {
 704                         iters = DEFAULT_PBKDF2_ITERATIONS;
 705                         ret = nvlist_add_uint64(props,
 706                             zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), iters);
 707                         if (ret != 0)
 708                                 goto error;
 709                 } else if (ret != 0) {
 710                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 711                             "Failed to get pbkdf2 iterations."));
 712                         goto error;
 713                 }
 714         } else {
 715                 /* check that pbkdf2iters was not specified by the user */
 716                 ret = nvlist_lookup_uint64(props,
 717                     zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), &iters);
 718                 if (ret == 0) {
 719                         ret = EINVAL;
 720                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 721                             "Cannot specify pbkdf2iters with a non-passphrase "
 722                             "keyformat."));
 723                         goto error;
 724                 }
 725         }
 726
 727         /* derive a key from the key material */
 728         ret = derive_key(hdl, keyformat, iters, key_material, key_material_len,
 729             salt, &key_data);
 730         if (ret != 0)
 731                 goto error;
 732
 733         free(key_material);
 734
 735         *wkeydata = key_data;
 736         *wkeylen = WRAPPING_KEY_LEN;
 737         return (0);
 738
 739 error:
 740         if (key_material != NULL)
 741                 free(key_material);
 742         if (key_data != NULL)
 743                 free(key_data);
 744
 745         *wkeydata = NULL;
 746         *wkeylen = 0;
 747         return (ret);
 748 }
 749
 750 static boolean_t
 751 proplist_has_encryption_props(nvlist_t *props)
 752 {
 753         int ret;
 754         uint64_t intval;
 755         char *strval;
 756
 757         ret = nvlist_lookup_uint64(props,
 758             zfs_prop_to_name(ZFS_PROP_ENCRYPTION), &intval);
 759         if (ret == 0 && intval != ZIO_CRYPT_OFF)
 760                 return (B_TRUE);
 761
 762         ret = nvlist_lookup_string(props,
 763             zfs_prop_to_name(ZFS_PROP_KEYLOCATION), &strval);
 764         if (ret == 0 && strcmp(strval, "none") != 0)
 765                 return (B_TRUE);
 766
 767         ret = nvlist_lookup_uint64(props,
 768             zfs_prop_to_name(ZFS_PROP_KEYFORMAT), &intval);
 769         if (ret == 0)
 770                 return (B_TRUE);
 771
 772         ret = nvlist_lookup_uint64(props,
 773             zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS), &intval);
 774         if (ret == 0)
 775                 return (B_TRUE);
 776
 777         return (B_FALSE);
 778 }
 779
 780 int
 781 zfs_crypto_get_encryption_root(zfs_handle_t *zhp, boolean_t *is_encroot,
 782     char *buf)
 783 {
 784         int ret;
 785         char prop_encroot[MAXNAMELEN];
 786
 787         /* if the dataset isn't encrypted, just return */
 788         if (zfs_prop_get_int(zhp, ZFS_PROP_ENCRYPTION) == ZIO_CRYPT_OFF) {
 789                 *is_encroot = B_FALSE;
 790                 if (buf != NULL)
 791                         buf[0] = '\0';
 792                 return (0);
 793         }
 794
 795         ret = zfs_prop_get(zhp, ZFS_PROP_ENCRYPTION_ROOT, prop_encroot,
 796             sizeof (prop_encroot), NULL, NULL, 0, B_TRUE);
 797         if (ret != 0) {
 798                 *is_encroot = B_FALSE;
 799                 if (buf != NULL)
 800                         buf[0] = '\0';
 801                 return (ret);
 802         }
 803
 804         *is_encroot = strcmp(prop_encroot, zfs_get_name(zhp)) == 0;
 805         if (buf != NULL)
 806                 strcpy(buf, prop_encroot);
 807
 808         return (0);
 809 }
 810
 811 int
 812 zfs_crypto_create(libzfs_handle_t *hdl, char *parent_name, nvlist_t *props,
 813     nvlist_t *pool_props, boolean_t stdin_available, uint8_t **wkeydata_out,
 814     uint_t *wkeylen_out)
 815 {
 816         int ret;
 817         char errbuf[1024];
 818         uint64_t crypt = ZIO_CRYPT_INHERIT, pcrypt = ZIO_CRYPT_INHERIT;
 819         uint64_t keyformat = ZFS_KEYFORMAT_NONE;
 820         char *keylocation = NULL;
 821         zfs_handle_t *pzhp = NULL;
 822         uint8_t *wkeydata = NULL;
 823         uint_t wkeylen = 0;
 824         boolean_t local_crypt = B_TRUE;
 825
 826         (void) snprintf(errbuf, sizeof (errbuf),
 827             dgettext(TEXT_DOMAIN, "Encryption create error"));
 828
 829         /* lookup crypt from props */
 830         ret = nvlist_lookup_uint64(props,
 831             zfs_prop_to_name(ZFS_PROP_ENCRYPTION), &crypt);
 832         if (ret != 0)
 833                 local_crypt = B_FALSE;
 834
 835         /* lookup key location and format from props */
 836         (void) nvlist_lookup_uint64(props,
 837             zfs_prop_to_name(ZFS_PROP_KEYFORMAT), &keyformat);
 838         (void) nvlist_lookup_string(props,
 839             zfs_prop_to_name(ZFS_PROP_KEYLOCATION), &keylocation);
 840
 841         if (parent_name != NULL) {
 842                 /* get a reference to parent dataset */
 843                 pzhp = make_dataset_handle(hdl, parent_name);
 844                 if (pzhp == NULL) {
 845                         ret = ENOENT;
 846                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 847                             "Failed to lookup parent."));
 848                         goto out;
 849                 }
 850
 851                 /* Lookup parent's crypt */
 852                 pcrypt = zfs_prop_get_int(pzhp, ZFS_PROP_ENCRYPTION);
 853
 854                 /* Params require the encryption feature */
 855                 if (!encryption_feature_is_enabled(pzhp->zpool_hdl)) {
 856                         if (proplist_has_encryption_props(props)) {
 857                                 ret = EINVAL;
 858                                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 859                                     "Encryption feature not enabled."));
 860                                 goto out;
 861                         }
 862
 863                         ret = 0;
 864                         goto out;
 865                 }
 866         } else {
 867                 /*
 868                  * special case for root dataset where encryption feature
 869                  * feature won't be on disk yet
 870                  */
 871                 if (!nvlist_exists(pool_props, "feature@encryption")) {
 872                         if (proplist_has_encryption_props(props)) {
 873                                 ret = EINVAL;
 874                                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 875                                     "Encryption feature not enabled."));
 876                                 goto out;
 877                         }
 878
 879                         ret = 0;
 880                         goto out;
 881                 }
 882
 883                 pcrypt = ZIO_CRYPT_OFF;
 884         }
 885
 886         /* Get the inherited encryption property if we don't have it locally */
 887         if (!local_crypt)
 888                 crypt = pcrypt;
 889
 890         /*
 891          * At this point crypt should be the actual encryption value. If
 892          * encryption is off just verify that no encryption properties have
 893          * been specified and return.
 894          */
 895         if (crypt == ZIO_CRYPT_OFF) {
 896                 if (proplist_has_encryption_props(props)) {
 897                         ret = EINVAL;
 898                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 899                             "Encryption must be turned on to set encryption "
 900                             "properties."));
 901                         goto out;
 902                 }
 903
 904                 ret = 0;
 905                 goto out;
 906         }
 907
 908         /*
 909          * If we have a parent crypt it is valid to specify encryption alone.
 910          * This will result in a child that is encrypted with the chosen
 911          * encryption suite that will also inherit the parent's key. If
 912          * the parent is not encrypted we need an encryption suite provided.
 913          */
 914         if (pcrypt == ZIO_CRYPT_OFF && keylocation == NULL &&
 915             keyformat == ZFS_KEYFORMAT_NONE) {
 916                 ret = EINVAL;
 917                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 918                     "Keyformat required for new encryption root."));
 919                 goto out;
 920         }
 921
 922         /*
 923          * Specifying a keylocation implies this will be a new encryption root.
 924          * Check that a keyformat is also specified.
 925          */
 926         if (keylocation != NULL && keyformat == ZFS_KEYFORMAT_NONE) {
 927                 ret = EINVAL;
 928                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 929                     "Keyformat required for new encryption root."));
 930                 goto out;
 931         }
 932
 933         /* default to prompt if no keylocation is specified */
 934         if (keyformat != ZFS_KEYFORMAT_NONE && keylocation == NULL) {
 935                 keylocation = "prompt";
 936                 ret = nvlist_add_string(props,
 937                     zfs_prop_to_name(ZFS_PROP_KEYLOCATION), keylocation);
 938                 if (ret != 0)
 939                         goto out;
 940         }
 941
 942         /*
 943          * If a local key is provided, this dataset will be a new
 944          * encryption root. Populate the encryption params.
 945          */
 946         if (keylocation != NULL) {
 947                 /*
 948                  * 'zfs recv -o keylocation=prompt' won't work because stdin
 949                  * is being used by the send stream, so we disallow it.
 950                  */
 951                 if (!stdin_available && strcmp(keylocation, "prompt") == 0) {
 952                         ret = EINVAL;
 953                         zfs_error_aux(hdl, dgettext(TEXT_DOMAIN, "Cannot use "
 954                             "'prompt' keylocation because stdin is in use."));
 955                         goto out;
 956                 }
 957
 958                 ret = populate_create_encryption_params_nvlists(hdl, NULL,
 959                     B_FALSE, keyformat, keylocation, props, &wkeydata,
 960                     &wkeylen);
 961                 if (ret != 0)
 962                         goto out;
 963         }
 964
 965         if (pzhp != NULL)
 966                 zfs_close(pzhp);
 967
 968         *wkeydata_out = wkeydata;
 969         *wkeylen_out = wkeylen;
 970         return (0);
 971
 972 out:
 973         if (pzhp != NULL)
 974                 zfs_close(pzhp);
 975         if (wkeydata != NULL)
 976                 free(wkeydata);
 977
 978         *wkeydata_out = NULL;
 979         *wkeylen_out = 0;
 980         return (ret);
 981 }
 982
 983 int
 984 zfs_crypto_clone_check(libzfs_handle_t *hdl, zfs_handle_t *origin_zhp,
 985     char *parent_name, nvlist_t *props)
 986 {
 987         char errbuf[1024];
 988
 989         (void) snprintf(errbuf, sizeof (errbuf),
 990             dgettext(TEXT_DOMAIN, "Encryption clone error"));
 991
 992         /*
 993          * No encryption properties should be specified. They will all be
 994          * inherited from the origin dataset.
 995          */
 996         if (nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_KEYFORMAT)) ||
 997             nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_KEYLOCATION)) ||
 998             nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_ENCRYPTION)) ||
 999             nvlist_exists(props, zfs_prop_to_name(ZFS_PROP_PBKDF2_ITERS))) {
1000                 zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
1001                     "Encryption properties must inherit from origin dataset."));
1002                 return (EINVAL);
1003         }
1004
1005         return (0);
1006 }
1007
1008 typedef struct loadkeys_cbdata {
1009         uint64_t cb_numfailed;
1010         uint64_t cb_numattempted;
1011 } loadkey_cbdata_t;
1012
1013 static int
1014 load_keys_cb(zfs_handle_t *zhp, void *arg)
1015 {
1016         int ret;
1017         boolean_t is_encroot;
1018         loadkey_cbdata_t *cb = arg;
1019         uint64_t keystatus = zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS);
1020
1021         /* only attempt to load keys for encryption roots */
1022         ret = zfs_crypto_get_encryption_root(zhp, &is_encroot, NULL);
1023         if (ret != 0 || !is_encroot)
1024                 goto out;
1025
1026         /* don't attempt to load already loaded keys */
1027         if (keystatus == ZFS_KEYSTATUS_AVAILABLE)
1028                 goto out;
1029
1030         /* Attempt to load the key. Record status in cb. */
1031         cb->cb_numattempted++;
1032
1033         ret = zfs_crypto_load_key(zhp, B_FALSE, NULL);
1034         if (ret)
1035                 cb->cb_numfailed++;
1036
1037 out:
1038         (void) zfs_iter_filesystems(zhp, load_keys_cb, cb);
1039         zfs_close(zhp);
1040
1041         /* always return 0, since this function is best effort */
1042         return (0);
1043 }
1044
1045 /*
1046  * This function is best effort. It attempts to load all the keys for the given
1047  * filesystem and all of its children.
1048  */
1049 int
1050 zfs_crypto_attempt_load_keys(libzfs_handle_t *hdl, char *fsname)
1051 {
1052         int ret;
1053         zfs_handle_t *zhp = NULL;
1054         loadkey_cbdata_t cb = { 0 };
1055
1056         zhp = zfs_open(hdl, fsname, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME);
1057         if (zhp == NULL) {
1058                 ret = ENOENT;
1059                 goto error;
1060         }
1061
1062         ret = load_keys_cb(zfs_handle_dup(zhp), &cb);
1063         if (ret)
1064                 goto error;
1065
1066         (void) printf(gettext("%llu / %llu keys successfully loaded\n"),
1067             (u_longlong_t)(cb.cb_numattempted - cb.cb_numfailed),
1068             (u_longlong_t)cb.cb_numattempted);
1069
1070         if (cb.cb_numfailed != 0) {
1071                 ret = -1;
1072                 goto error;
1073         }
1074
1075         zfs_close(zhp);
1076         return (0);
1077
1078 error:
1079         if (zhp != NULL)
1080                 zfs_close(zhp);
1081         return (ret);
1082 }
1083
1084 int
1085 zfs_crypto_load_key(zfs_handle_t *zhp, boolean_t noop, char *alt_keylocation)
1086 {
1087         int ret, attempts = 0;
1088         char errbuf[1024];
1089         uint64_t keystatus, iters = 0, salt = 0;
1090         uint64_t keyformat = ZFS_KEYFORMAT_NONE;
1091         char prop_keylocation[MAXNAMELEN];
1092         char prop_encroot[MAXNAMELEN];
1093         char *keylocation = NULL;
1094         uint8_t *key_material = NULL, *key_data = NULL;
1095         size_t key_material_len;
1096         boolean_t is_encroot, can_retry = B_FALSE, correctible = B_FALSE;
1097
1098         (void) snprintf(errbuf, sizeof (errbuf),
1099             dgettext(TEXT_DOMAIN, "Key load error"));
1100
1101         /* check that encryption is enabled for the pool */
1102         if (!encryption_feature_is_enabled(zhp->zpool_hdl)) {
1103                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1104                     "Encryption feature not enabled."));
1105                 ret = EINVAL;
1106                 goto error;
1107         }
1108
1109         /* Fetch the keyformat. Check that the dataset is encrypted. */
1110         keyformat = zfs_prop_get_int(zhp, ZFS_PROP_KEYFORMAT);
1111         if (keyformat == ZFS_KEYFORMAT_NONE) {
1112                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1113                     "'%s' is not encrypted."), zfs_get_name(zhp));
1114                 ret = EINVAL;
1115                 goto error;
1116         }
1117
1118         /*
1119          * Fetch the key location. Check that we are working with an
1120          * encryption root.
1121          */
1122         ret = zfs_crypto_get_encryption_root(zhp, &is_encroot, prop_encroot);
1123         if (ret != 0) {
1124                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1125                     "Failed to get encryption root for '%s'."),
1126                     zfs_get_name(zhp));
1127                 goto error;
1128         } else if (!is_encroot) {
1129                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1130                     "Keys must be loaded for encryption root of '%s' (%s)."),
1131                     zfs_get_name(zhp), prop_encroot);
1132                 ret = EINVAL;
1133                 goto error;
1134         }
1135
1136         /*
1137          * if the caller has elected to override the keylocation property
1138          * use that instead
1139          */
1140         if (alt_keylocation != NULL) {
1141                 keylocation = alt_keylocation;
1142         } else {
1143                 ret = zfs_prop_get(zhp, ZFS_PROP_KEYLOCATION, prop_keylocation,
1144                     sizeof (prop_keylocation), NULL, NULL, 0, B_TRUE);
1145                 if (ret != 0) {
1146                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1147                             "Failed to get keylocation for '%s'."),
1148                             zfs_get_name(zhp));
1149                         goto error;
1150                 }
1151
1152                 keylocation = prop_keylocation;
1153         }
1154
1155         /* check that the key is unloaded unless this is a noop */
1156         if (!noop) {
1157                 keystatus = zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS);
1158                 if (keystatus == ZFS_KEYSTATUS_AVAILABLE) {
1159                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1160                             "Key already loaded for '%s'."), zfs_get_name(zhp));
1161                         ret = EEXIST;
1162                         goto error;
1163                 }
1164         }
1165
1166         /* passphrase formats require a salt and pbkdf2_iters property */
1167         if (keyformat == ZFS_KEYFORMAT_PASSPHRASE) {
1168                 salt = zfs_prop_get_int(zhp, ZFS_PROP_PBKDF2_SALT);
1169                 iters = zfs_prop_get_int(zhp, ZFS_PROP_PBKDF2_ITERS);
1170         }
1171
1172 try_again:
1173         /* fetching and deriving the key are correctable errors. set the flag */
1174         correctible = B_TRUE;
1175
1176         /* get key material from key format and location */
1177         ret = get_key_material(zhp->zfs_hdl, B_FALSE, B_FALSE, keyformat,
1178             keylocation, zfs_get_name(zhp), &key_material, &key_material_len,
1179             &can_retry);
1180         if (ret != 0)
1181                 goto error;
1182
1183         /* derive a key from the key material */
1184         ret = derive_key(zhp->zfs_hdl, keyformat, iters, key_material,
1185             key_material_len, salt, &key_data);
1186         if (ret != 0)
1187                 goto error;
1188
1189         correctible = B_FALSE;
1190
1191         /* pass the wrapping key and noop flag to the ioctl */
1192         ret = lzc_load_key(zhp->zfs_name, noop, key_data, WRAPPING_KEY_LEN);
1193         if (ret != 0) {
1194                 switch (ret) {
1195                 case EPERM:
1196                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1197                             "Permission denied."));
1198                         break;
1199                 case EINVAL:
1200                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1201                             "Invalid parameters provided for dataset %s."),
1202                             zfs_get_name(zhp));
1203                         break;
1204                 case EEXIST:
1205                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1206                             "Key already loaded for '%s'."), zfs_get_name(zhp));
1207                         break;
1208                 case EBUSY:
1209                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1210                             "'%s' is busy."), zfs_get_name(zhp));
1211                         break;
1212                 case EACCES:
1213                         correctible = B_TRUE;
1214                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1215                             "Incorrect key provided for '%s'."),
1216                             zfs_get_name(zhp));
1217                         break;
1218                 }
1219                 goto error;
1220         }
1221
1222         free(key_material);
1223         free(key_data);
1224
1225         return (0);
1226
1227 error:
1228         zfs_error(zhp->zfs_hdl, EZFS_CRYPTOFAILED, errbuf);
1229         if (key_material != NULL) {
1230                 free(key_material);
1231                 key_material = NULL;
1232         }
1233         if (key_data != NULL) {
1234                 free(key_data);
1235                 key_data = NULL;
1236         }
1237
1238         /*
1239          * Here we decide if it is ok to allow the user to retry entering their
1240          * key. The can_retry flag will be set if the user is entering their
1241          * key from an interactive prompt. The correctable flag will only be
1242          * set if an error that occurred could be corrected by retrying. Both
1243          * flags are needed to allow the user to attempt key entry again
1244          */
1245         attempts++;
1246         if (can_retry && correctible && attempts < MAX_KEY_PROMPT_ATTEMPTS)
1247                 goto try_again;
1248
1249         return (ret);
1250 }
1251
1252 int
1253 zfs_crypto_unload_key(zfs_handle_t *zhp)
1254 {
1255         int ret;
1256         char errbuf[1024];
1257         char prop_encroot[MAXNAMELEN];
1258         uint64_t keystatus, keyformat;
1259         boolean_t is_encroot;
1260
1261         (void) snprintf(errbuf, sizeof (errbuf),
1262             dgettext(TEXT_DOMAIN, "Key unload error"));
1263
1264         /* check that encryption is enabled for the pool */
1265         if (!encryption_feature_is_enabled(zhp->zpool_hdl)) {
1266                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1267                     "Encryption feature not enabled."));
1268                 ret = EINVAL;
1269                 goto error;
1270         }
1271
1272         /* Fetch the keyformat. Check that the dataset is encrypted. */
1273         keyformat = zfs_prop_get_int(zhp, ZFS_PROP_KEYFORMAT);
1274         if (keyformat == ZFS_KEYFORMAT_NONE) {
1275                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1276                     "'%s' is not encrypted."), zfs_get_name(zhp));
1277                 ret = EINVAL;
1278                 goto error;
1279         }
1280
1281         /*
1282          * Fetch the key location. Check that we are working with an
1283          * encryption root.
1284          */
1285         ret = zfs_crypto_get_encryption_root(zhp, &is_encroot, prop_encroot);
1286         if (ret != 0) {
1287                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1288                     "Failed to get encryption root for '%s'."),
1289                     zfs_get_name(zhp));
1290                 goto error;
1291         } else if (!is_encroot) {
1292                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1293                     "Keys must be unloaded for encryption root of '%s' (%s)."),
1294                     zfs_get_name(zhp), prop_encroot);
1295                 ret = EINVAL;
1296                 goto error;
1297         }
1298
1299         /* check that the key is loaded */
1300         keystatus = zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS);
1301         if (keystatus == ZFS_KEYSTATUS_UNAVAILABLE) {
1302                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1303                     "Key already unloaded for '%s'."), zfs_get_name(zhp));
1304                 ret = EACCES;
1305                 goto error;
1306         }
1307
1308         /* call the ioctl */
1309         ret = lzc_unload_key(zhp->zfs_name);
1310
1311         if (ret != 0) {
1312                 switch (ret) {
1313                 case EPERM:
1314                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1315                             "Permission denied."));
1316                         break;
1317                 case EACCES:
1318                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1319                             "Key already unloaded for '%s'."),
1320                             zfs_get_name(zhp));
1321                         break;
1322                 case EBUSY:
1323                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1324                             "'%s' is busy."), zfs_get_name(zhp));
1325                         break;
1326                 }
1327                 zfs_error(zhp->zfs_hdl, EZFS_CRYPTOFAILED, errbuf);
1328         }
1329
1330         return (ret);
1331
1332 error:
1333         zfs_error(zhp->zfs_hdl, EZFS_CRYPTOFAILED, errbuf);
1334         return (ret);
1335 }
1336
1337 static int
1338 zfs_crypto_verify_rewrap_nvlist(zfs_handle_t *zhp, nvlist_t *props,
1339     nvlist_t **props_out, char *errbuf)
1340 {
1341         int ret;
1342         nvpair_t *elem = NULL;
1343         zfs_prop_t prop;
1344         nvlist_t *new_props = NULL;
1345
1346         new_props = fnvlist_alloc();
1347
1348         /*
1349          * loop through all provided properties, we should only have
1350          * keyformat, keylocation and pbkdf2iters. The actual validation of
1351          * values is done by zfs_valid_proplist().
1352          */
1353         while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
1354                 const char *propname = nvpair_name(elem);
1355                 prop = zfs_name_to_prop(propname);
1356
1357                 switch (prop) {
1358                 case ZFS_PROP_PBKDF2_ITERS:
1359                 case ZFS_PROP_KEYFORMAT:
1360                 case ZFS_PROP_KEYLOCATION:
1361                         break;
1362                 default:
1363                         ret = EINVAL;
1364                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1365                             "Only keyformat, keylocation and pbkdf2iters may "
1366                             "be set with this command."));
1367                         goto error;
1368                 }
1369         }
1370
1371         new_props = zfs_valid_proplist(zhp->zfs_hdl, zhp->zfs_type, props,
1372             zfs_prop_get_int(zhp, ZFS_PROP_ZONED), NULL, zhp->zpool_hdl,
1373             B_TRUE, errbuf);
1374         if (new_props == NULL) {
1375                 ret = EINVAL;
1376                 goto error;
1377         }
1378
1379         *props_out = new_props;
1380         return (0);
1381
1382 error:
1383         nvlist_free(new_props);
1384         *props_out = NULL;
1385         return (ret);
1386 }
1387
1388 int
1389 zfs_crypto_rewrap(zfs_handle_t *zhp, nvlist_t *raw_props, boolean_t inheritkey)
1390 {
1391         int ret;
1392         char errbuf[1024];
1393         boolean_t is_encroot;
1394         nvlist_t *props = NULL;
1395         uint8_t *wkeydata = NULL;
1396         uint_t wkeylen = 0;
1397         dcp_cmd_t cmd = (inheritkey) ? DCP_CMD_INHERIT : DCP_CMD_NEW_KEY;
1398         uint64_t crypt, pcrypt, keystatus, pkeystatus;
1399         uint64_t keyformat = ZFS_KEYFORMAT_NONE;
1400         zfs_handle_t *pzhp = NULL;
1401         char *keylocation = NULL;
1402         char origin_name[MAXNAMELEN];
1403         char prop_keylocation[MAXNAMELEN];
1404         char parent_name[ZFS_MAX_DATASET_NAME_LEN];
1405
1406         (void) snprintf(errbuf, sizeof (errbuf),
1407             dgettext(TEXT_DOMAIN, "Key change error"));
1408
1409         /* check that encryption is enabled for the pool */
1410         if (!encryption_feature_is_enabled(zhp->zpool_hdl)) {
1411                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1412                     "Encryption feature not enabled."));
1413                 ret = EINVAL;
1414                 goto error;
1415         }
1416
1417         /* get crypt from dataset */
1418         crypt = zfs_prop_get_int(zhp, ZFS_PROP_ENCRYPTION);
1419         if (crypt == ZIO_CRYPT_OFF) {
1420                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1421                     "Dataset not encrypted."));
1422                 ret = EINVAL;
1423                 goto error;
1424         }
1425
1426         /* get the encryption root of the dataset */
1427         ret = zfs_crypto_get_encryption_root(zhp, &is_encroot, NULL);
1428         if (ret != 0) {
1429                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1430                     "Failed to get encryption root for '%s'."),
1431                     zfs_get_name(zhp));
1432                 goto error;
1433         }
1434
1435         /* Clones use their origin's key and cannot rewrap it */
1436         ret = zfs_prop_get(zhp, ZFS_PROP_ORIGIN, origin_name,
1437             sizeof (origin_name), NULL, NULL, 0, B_TRUE);
1438         if (ret == 0 && strcmp(origin_name, "") != 0) {
1439                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1440                     "Keys cannot be changed on clones."));
1441                 ret = EINVAL;
1442                 goto error;
1443         }
1444
1445         /*
1446          * If the user wants to use the inheritkey variant of this function
1447          * we don't need to collect any crypto arguments.
1448          */
1449         if (!inheritkey) {
1450                 /* validate the provided properties */
1451                 ret = zfs_crypto_verify_rewrap_nvlist(zhp, raw_props, &props,
1452                     errbuf);
1453                 if (ret != 0)
1454                         goto error;
1455
1456                 /*
1457                  * Load keyformat and keylocation from the nvlist. Fetch from
1458                  * the dataset properties if not specified.
1459                  */
1460                 (void) nvlist_lookup_uint64(props,
1461                     zfs_prop_to_name(ZFS_PROP_KEYFORMAT), &keyformat);
1462                 (void) nvlist_lookup_string(props,
1463                     zfs_prop_to_name(ZFS_PROP_KEYLOCATION), &keylocation);
1464
1465                 if (is_encroot) {
1466                         /*
1467                          * If this is already an encryption root, just keep
1468                          * any properties not set by the user.
1469                          */
1470                         if (keyformat == ZFS_KEYFORMAT_NONE) {
1471                                 keyformat = zfs_prop_get_int(zhp,
1472                                     ZFS_PROP_KEYFORMAT);
1473                                 ret = nvlist_add_uint64(props,
1474                                     zfs_prop_to_name(ZFS_PROP_KEYFORMAT),
1475                                     keyformat);
1476                                 if (ret != 0) {
1477                                         zfs_error_aux(zhp->zfs_hdl,
1478                                             dgettext(TEXT_DOMAIN, "Failed to "
1479                                             "get existing keyformat "
1480                                             "property."));
1481                                         goto error;
1482                                 }
1483                         }
1484
1485                         if (keylocation == NULL) {
1486                                 ret = zfs_prop_get(zhp, ZFS_PROP_KEYLOCATION,
1487                                     prop_keylocation, sizeof (prop_keylocation),
1488                                     NULL, NULL, 0, B_TRUE);
1489                                 if (ret != 0) {
1490                                         zfs_error_aux(zhp->zfs_hdl,
1491                                             dgettext(TEXT_DOMAIN, "Failed to "
1492                                             "get existing keylocation "
1493                                             "property."));
1494                                         goto error;
1495                                 }
1496
1497                                 keylocation = prop_keylocation;
1498                         }
1499                 } else {
1500                         /* need a new key for non-encryption roots */
1501                         if (keyformat == ZFS_KEYFORMAT_NONE) {
1502                                 ret = EINVAL;
1503                                 zfs_error_aux(zhp->zfs_hdl,
1504                                     dgettext(TEXT_DOMAIN, "Keyformat required "
1505                                     "for new encryption root."));
1506                                 goto error;
1507                         }
1508
1509                         /* default to prompt if no keylocation is specified */
1510                         if (keylocation == NULL) {
1511                                 keylocation = "prompt";
1512                                 ret = nvlist_add_string(props,
1513                                     zfs_prop_to_name(ZFS_PROP_KEYLOCATION),
1514                                     keylocation);
1515                                 if (ret != 0)
1516                                         goto error;
1517                         }
1518                 }
1519
1520                 /* fetch the new wrapping key and associated properties */
1521                 ret = populate_create_encryption_params_nvlists(zhp->zfs_hdl,
1522                     zhp, B_TRUE, keyformat, keylocation, props, &wkeydata,
1523                     &wkeylen);
1524                 if (ret != 0)
1525                         goto error;
1526         } else {
1527                 /* check that zhp is an encryption root */
1528                 if (!is_encroot) {
1529                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1530                             "Key inheritting can only be performed on "
1531                             "encryption roots."));
1532                         ret = EINVAL;
1533                         goto error;
1534                 }
1535
1536                 /* get the parent's name */
1537                 ret = zfs_parent_name(zhp, parent_name, sizeof (parent_name));
1538                 if (ret != 0) {
1539                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1540                             "Root dataset cannot inherit key."));
1541                         ret = EINVAL;
1542                         goto error;
1543                 }
1544
1545                 /* get a handle to the parent */
1546                 pzhp = make_dataset_handle(zhp->zfs_hdl, parent_name);
1547                 if (pzhp == NULL) {
1548                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1549                             "Failed to lookup parent."));
1550                         ret = ENOENT;
1551                         goto error;
1552                 }
1553
1554                 /* parent must be encrypted */
1555                 pcrypt = zfs_prop_get_int(pzhp, ZFS_PROP_ENCRYPTION);
1556                 if (pcrypt == ZIO_CRYPT_OFF) {
1557                         zfs_error_aux(pzhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1558                             "Parent must be encrypted."));
1559                         ret = EINVAL;
1560                         goto error;
1561                 }
1562
1563                 /* check that the parent's key is loaded */
1564                 pkeystatus = zfs_prop_get_int(pzhp, ZFS_PROP_KEYSTATUS);
1565                 if (pkeystatus == ZFS_KEYSTATUS_UNAVAILABLE) {
1566                         zfs_error_aux(pzhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1567                             "Parent key must be loaded."));
1568                         ret = EACCES;
1569                         goto error;
1570                 }
1571         }
1572
1573         /* check that the key is loaded */
1574         keystatus = zfs_prop_get_int(zhp, ZFS_PROP_KEYSTATUS);
1575         if (keystatus == ZFS_KEYSTATUS_UNAVAILABLE) {
1576                 zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1577                     "Key must be loaded."));
1578                 ret = EACCES;
1579                 goto error;
1580         }
1581
1582         /* call the ioctl */
1583         ret = lzc_change_key(zhp->zfs_name, cmd, props, wkeydata, wkeylen);
1584         if (ret != 0) {
1585                 switch (ret) {
1586                 case EPERM:
1587                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1588                             "Permission denied."));
1589                         break;
1590                 case EINVAL:
1591                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1592                             "Invalid properties for key change."));
1593                         break;
1594                 case EACCES:
1595                         zfs_error_aux(zhp->zfs_hdl, dgettext(TEXT_DOMAIN,
1596                             "Key is not currently loaded."));
1597                         break;
1598                 }
1599                 zfs_error(zhp->zfs_hdl, EZFS_CRYPTOFAILED, errbuf);
1600         }
1601
1602         if (pzhp != NULL)
1603                 zfs_close(pzhp);
1604         if (props != NULL)
1605                 nvlist_free(props);
1606         if (wkeydata != NULL)
1607                 free(wkeydata);
1608
1609         return (ret);
1610
1611 error:
1612         if (pzhp != NULL)
1613                 zfs_close(pzhp);
1614         if (props != NULL)
1615                 nvlist_free(props);
1616         if (wkeydata != NULL)
1617                 free(wkeydata);
1618
1619         zfs_error(zhp->zfs_hdl, EZFS_CRYPTOFAILED, errbuf);
1620         return (ret);
1621 }