block/crypto.c

   1 /*
   2  * QEMU block full disk encryption
   3  *
   4  * Copyright (c) 2015-2016 Red Hat, Inc.
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #include "qemu/osdep.h"
  22
  23 #include "block/block_int.h"
  24 #include "block/qdict.h"
  25 #include "sysemu/block-backend.h"
  26 #include "crypto/block.h"
  27 #include "qapi/opts-visitor.h"
  28 #include "qapi/qapi-visit-crypto.h"
  29 #include "qapi/qobject-input-visitor.h"
  30 #include "qapi/error.h"
  31 #include "qemu/option.h"
  32 #include "crypto.h"
  33
  34 typedef struct BlockCrypto BlockCrypto;
  35
  36 struct BlockCrypto {
  37     QCryptoBlock *block;
  38 };
  39
  40
  41 static int block_crypto_probe_generic(QCryptoBlockFormat format,
  42                                       const uint8_t *buf,
  43                                       int buf_size,
  44                                       const char *filename)
  45 {
  46     if (qcrypto_block_has_format(format, buf, buf_size)) {
  47         return 100;
  48     } else {
  49         return 0;
  50     }
  51 }
  52
  53
  54 static ssize_t block_crypto_read_func(QCryptoBlock *block,
  55                                       size_t offset,
  56                                       uint8_t *buf,
  57                                       size_t buflen,
  58                                       void *opaque,
  59                                       Error **errp)
  60 {
  61     BlockDriverState *bs = opaque;
  62     ssize_t ret;
  63
  64     ret = bdrv_pread(bs->file, offset, buf, buflen);
  65     if (ret < 0) {
  66         error_setg_errno(errp, -ret, "Could not read encryption header");
  67         return ret;
  68     }
  69     return ret;
  70 }
  71
  72
  73 struct BlockCryptoCreateData {
  74     BlockBackend *blk;
  75     uint64_t size;
  76 };
  77
  78
  79 static ssize_t block_crypto_write_func(QCryptoBlock *block,
  80                                        size_t offset,
  81                                        const uint8_t *buf,
  82                                        size_t buflen,
  83                                        void *opaque,
  84                                        Error **errp)
  85 {
  86     struct BlockCryptoCreateData *data = opaque;
  87     ssize_t ret;
  88
  89     ret = blk_pwrite(data->blk, offset, buf, buflen, 0);
  90     if (ret < 0) {
  91         error_setg_errno(errp, -ret, "Could not write encryption header");
  92         return ret;
  93     }
  94     return ret;
  95 }
  96
  97
  98 static ssize_t block_crypto_init_func(QCryptoBlock *block,
  99                                       size_t headerlen,
 100                                       void *opaque,
 101                                       Error **errp)
 102 {
 103     struct BlockCryptoCreateData *data = opaque;
 104
 105     if (data->size > INT64_MAX || headerlen > INT64_MAX - data->size) {
 106         error_setg(errp, "The requested file size is too large");
 107         return -EFBIG;
 108     }
 109
 110     /* User provided size should reflect amount of space made
 111      * available to the guest, so we must take account of that
 112      * which will be used by the crypto header
 113      */
 114     return blk_truncate(data->blk, data->size + headerlen, PREALLOC_MODE_OFF,
 115                         errp);
 116 }
 117
 118
 119 static QemuOptsList block_crypto_runtime_opts_luks = {
 120     .name = "crypto",
 121     .head = QTAILQ_HEAD_INITIALIZER(block_crypto_runtime_opts_luks.head),
 122     .desc = {
 123         BLOCK_CRYPTO_OPT_DEF_LUKS_KEY_SECRET(""),
 124         { /* end of list */ }
 125     },
 126 };
 127
 128
 129 static QemuOptsList block_crypto_create_opts_luks = {
 130     .name = "crypto",
 131     .head = QTAILQ_HEAD_INITIALIZER(block_crypto_create_opts_luks.head),
 132     .desc = {
 133         {
 134             .name = BLOCK_OPT_SIZE,
 135             .type = QEMU_OPT_SIZE,
 136             .help = "Virtual disk size"
 137         },
 138         BLOCK_CRYPTO_OPT_DEF_LUKS_KEY_SECRET(""),
 139         BLOCK_CRYPTO_OPT_DEF_LUKS_CIPHER_ALG(""),
 140         BLOCK_CRYPTO_OPT_DEF_LUKS_CIPHER_MODE(""),
 141         BLOCK_CRYPTO_OPT_DEF_LUKS_IVGEN_ALG(""),
 142         BLOCK_CRYPTO_OPT_DEF_LUKS_IVGEN_HASH_ALG(""),
 143         BLOCK_CRYPTO_OPT_DEF_LUKS_HASH_ALG(""),
 144         BLOCK_CRYPTO_OPT_DEF_LUKS_ITER_TIME(""),
 145         { /* end of list */ }
 146     },
 147 };
 148
 149
 150 QCryptoBlockOpenOptions *
 151 block_crypto_open_opts_init(QCryptoBlockFormat format,
 152                             QDict *opts,
 153                             Error **errp)
 154 {
 155     Visitor *v;
 156     QCryptoBlockOpenOptions *ret = NULL;
 157     Error *local_err = NULL;
 158
 159     ret = g_new0(QCryptoBlockOpenOptions, 1);
 160     ret->format = format;
 161
 162     v = qobject_input_visitor_new_flat_confused(opts, &local_err);
 163     if (local_err) {
 164         goto out;
 165     }
 166
 167     visit_start_struct(v, NULL, NULL, 0, &local_err);
 168     if (local_err) {
 169         goto out;
 170     }
 171
 172     switch (format) {
 173     case Q_CRYPTO_BLOCK_FORMAT_LUKS:
 174         visit_type_QCryptoBlockOptionsLUKS_members(
 175             v, &ret->u.luks, &local_err);
 176         break;
 177
 178     case Q_CRYPTO_BLOCK_FORMAT_QCOW:
 179         visit_type_QCryptoBlockOptionsQCow_members(
 180             v, &ret->u.qcow, &local_err);
 181         break;
 182
 183     default:
 184         error_setg(&local_err, "Unsupported block format %d", format);
 185         break;
 186     }
 187     if (!local_err) {
 188         visit_check_struct(v, &local_err);
 189     }
 190
 191     visit_end_struct(v, NULL);
 192
 193  out:
 194     if (local_err) {
 195         error_propagate(errp, local_err);
 196         qapi_free_QCryptoBlockOpenOptions(ret);
 197         ret = NULL;
 198     }
 199     visit_free(v);
 200     return ret;
 201 }
 202
 203
 204 QCryptoBlockCreateOptions *
 205 block_crypto_create_opts_init(QCryptoBlockFormat format,
 206                               QDict *opts,
 207                               Error **errp)
 208 {
 209     Visitor *v;
 210     QCryptoBlockCreateOptions *ret = NULL;
 211     Error *local_err = NULL;
 212
 213     ret = g_new0(QCryptoBlockCreateOptions, 1);
 214     ret->format = format;
 215
 216     v = qobject_input_visitor_new_flat_confused(opts, &local_err);
 217     if (local_err) {
 218         goto out;
 219     }
 220
 221     visit_start_struct(v, NULL, NULL, 0, &local_err);
 222     if (local_err) {
 223         goto out;
 224     }
 225
 226     switch (format) {
 227     case Q_CRYPTO_BLOCK_FORMAT_LUKS:
 228         visit_type_QCryptoBlockCreateOptionsLUKS_members(
 229             v, &ret->u.luks, &local_err);
 230         break;
 231
 232     case Q_CRYPTO_BLOCK_FORMAT_QCOW:
 233         visit_type_QCryptoBlockOptionsQCow_members(
 234             v, &ret->u.qcow, &local_err);
 235         break;
 236
 237     default:
 238         error_setg(&local_err, "Unsupported block format %d", format);
 239         break;
 240     }
 241     if (!local_err) {
 242         visit_check_struct(v, &local_err);
 243     }
 244
 245     visit_end_struct(v, NULL);
 246
 247  out:
 248     if (local_err) {
 249         error_propagate(errp, local_err);
 250         qapi_free_QCryptoBlockCreateOptions(ret);
 251         ret = NULL;
 252     }
 253     visit_free(v);
 254     return ret;
 255 }
 256
 257
 258 static int block_crypto_open_generic(QCryptoBlockFormat format,
 259                                      QemuOptsList *opts_spec,
 260                                      BlockDriverState *bs,
 261                                      QDict *options,
 262                                      int flags,
 263                                      Error **errp)
 264 {
 265     BlockCrypto *crypto = bs->opaque;
 266     QemuOpts *opts = NULL;
 267     Error *local_err = NULL;
 268     int ret = -EINVAL;
 269     QCryptoBlockOpenOptions *open_opts = NULL;
 270     unsigned int cflags = 0;
 271     QDict *cryptoopts = NULL;
 272
 273     bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
 274                                false, errp);
 275     if (!bs->file) {
 276         return -EINVAL;
 277     }
 278
 279     bs->supported_write_flags = BDRV_REQ_FUA &
 280         bs->file->bs->supported_write_flags;
 281
 282     opts = qemu_opts_create(opts_spec, NULL, 0, &error_abort);
 283     qemu_opts_absorb_qdict(opts, options, &local_err);
 284     if (local_err) {
 285         error_propagate(errp, local_err);
 286         goto cleanup;
 287     }
 288
 289     cryptoopts = qemu_opts_to_qdict(opts, NULL);
 290
 291     open_opts = block_crypto_open_opts_init(format, cryptoopts, errp);
 292     if (!open_opts) {
 293         goto cleanup;
 294     }
 295
 296     if (flags & BDRV_O_NO_IO) {
 297         cflags |= QCRYPTO_BLOCK_OPEN_NO_IO;
 298     }
 299     crypto->block = qcrypto_block_open(open_opts, NULL,
 300                                        block_crypto_read_func,
 301                                        bs,
 302                                        cflags,
 303                                        errp);
 304
 305     if (!crypto->block) {
 306         ret = -EIO;
 307         goto cleanup;
 308     }
 309
 310     bs->encrypted = true;
 311
 312     ret = 0;
 313  cleanup:
 314     qobject_unref(cryptoopts);
 315     qapi_free_QCryptoBlockOpenOptions(open_opts);
 316     return ret;
 317 }
 318
 319
 320 static int block_crypto_co_create_generic(BlockDriverState *bs,
 321                                           int64_t size,
 322                                           QCryptoBlockCreateOptions *opts,
 323                                           Error **errp)
 324 {
 325     int ret;
 326     BlockBackend *blk;
 327     QCryptoBlock *crypto = NULL;
 328     struct BlockCryptoCreateData data;
 329
 330     blk = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL);
 331
 332     ret = blk_insert_bs(blk, bs, errp);
 333     if (ret < 0) {
 334         goto cleanup;
 335     }
 336
 337     data = (struct BlockCryptoCreateData) {
 338         .blk = blk,
 339         .size = size,
 340     };
 341
 342     crypto = qcrypto_block_create(opts, NULL,
 343                                   block_crypto_init_func,
 344                                   block_crypto_write_func,
 345                                   &data,
 346                                   errp);
 347
 348     if (!crypto) {
 349         ret = -EIO;
 350         goto cleanup;
 351     }
 352
 353     ret = 0;
 354  cleanup:
 355     qcrypto_block_free(crypto);
 356     blk_unref(blk);
 357     return ret;
 358 }
 359
 360 static int block_crypto_truncate(BlockDriverState *bs, int64_t offset,
 361                                  PreallocMode prealloc, Error **errp)
 362 {
 363     BlockCrypto *crypto = bs->opaque;
 364     uint64_t payload_offset =
 365         qcrypto_block_get_payload_offset(crypto->block);
 366
 367     if (payload_offset > INT64_MAX - offset) {
 368         error_setg(errp, "The requested file size is too large");
 369         return -EFBIG;
 370     }
 371
 372     offset += payload_offset;
 373
 374     return bdrv_truncate(bs->file, offset, prealloc, errp);
 375 }
 376
 377 static void block_crypto_close(BlockDriverState *bs)
 378 {
 379     BlockCrypto *crypto = bs->opaque;
 380     qcrypto_block_free(crypto->block);
 381 }
 382
 383 static int block_crypto_reopen_prepare(BDRVReopenState *state,
 384                                        BlockReopenQueue *queue, Error **errp)
 385 {
 386     /* nothing needs checking */
 387     return 0;
 388 }
 389
 390 /*
 391  * 1 MB bounce buffer gives good performance / memory tradeoff
 392  * when using cache=none|directsync.
 393  */
 394 #define BLOCK_CRYPTO_MAX_IO_SIZE (1024 * 1024)
 395
 396 static coroutine_fn int
 397 block_crypto_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
 398                        QEMUIOVector *qiov, int flags)
 399 {
 400     BlockCrypto *crypto = bs->opaque;
 401     uint64_t cur_bytes; /* number of bytes in current iteration */
 402     uint64_t bytes_done = 0;
 403     uint8_t *cipher_data = NULL;
 404     QEMUIOVector hd_qiov;
 405     int ret = 0;
 406     uint64_t sector_size = qcrypto_block_get_sector_size(crypto->block);
 407     uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block);
 408
 409     assert(!flags);
 410     assert(payload_offset < INT64_MAX);
 411     assert(QEMU_IS_ALIGNED(offset, sector_size));
 412     assert(QEMU_IS_ALIGNED(bytes, sector_size));
 413
 414     qemu_iovec_init(&hd_qiov, qiov->niov);
 415
 416     /* Bounce buffer because we don't wish to expose cipher text
 417      * in qiov which points to guest memory.
 418      */
 419     cipher_data =
 420         qemu_try_blockalign(bs->file->bs, MIN(BLOCK_CRYPTO_MAX_IO_SIZE,
 421                                               qiov->size));
 422     if (cipher_data == NULL) {
 423         ret = -ENOMEM;
 424         goto cleanup;
 425     }
 426
 427     while (bytes) {
 428         cur_bytes = MIN(bytes, BLOCK_CRYPTO_MAX_IO_SIZE);
 429
 430         qemu_iovec_reset(&hd_qiov);
 431         qemu_iovec_add(&hd_qiov, cipher_data, cur_bytes);
 432
 433         ret = bdrv_co_preadv(bs->file, payload_offset + offset + bytes_done,
 434                              cur_bytes, &hd_qiov, 0);
 435         if (ret < 0) {
 436             goto cleanup;
 437         }
 438
 439         if (qcrypto_block_decrypt(crypto->block, offset + bytes_done,
 440                                   cipher_data, cur_bytes, NULL) < 0) {
 441             ret = -EIO;
 442             goto cleanup;
 443         }
 444
 445         qemu_iovec_from_buf(qiov, bytes_done, cipher_data, cur_bytes);
 446
 447         bytes -= cur_bytes;
 448         bytes_done += cur_bytes;
 449     }
 450
 451  cleanup:
 452     qemu_iovec_destroy(&hd_qiov);
 453     qemu_vfree(cipher_data);
 454
 455     return ret;
 456 }
 457
 458
 459 static coroutine_fn int
 460 block_crypto_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
 461                         QEMUIOVector *qiov, int flags)
 462 {
 463     BlockCrypto *crypto = bs->opaque;
 464     uint64_t cur_bytes; /* number of bytes in current iteration */
 465     uint64_t bytes_done = 0;
 466     uint8_t *cipher_data = NULL;
 467     QEMUIOVector hd_qiov;
 468     int ret = 0;
 469     uint64_t sector_size = qcrypto_block_get_sector_size(crypto->block);
 470     uint64_t payload_offset = qcrypto_block_get_payload_offset(crypto->block);
 471
 472     assert(!(flags & ~BDRV_REQ_FUA));
 473     assert(payload_offset < INT64_MAX);
 474     assert(QEMU_IS_ALIGNED(offset, sector_size));
 475     assert(QEMU_IS_ALIGNED(bytes, sector_size));
 476
 477     qemu_iovec_init(&hd_qiov, qiov->niov);
 478
 479     /* Bounce buffer because we're not permitted to touch
 480      * contents of qiov - it points to guest memory.
 481      */
 482     cipher_data =
 483         qemu_try_blockalign(bs->file->bs, MIN(BLOCK_CRYPTO_MAX_IO_SIZE,
 484                                               qiov->size));
 485     if (cipher_data == NULL) {
 486         ret = -ENOMEM;
 487         goto cleanup;
 488     }
 489
 490     while (bytes) {
 491         cur_bytes = MIN(bytes, BLOCK_CRYPTO_MAX_IO_SIZE);
 492
 493         qemu_iovec_to_buf(qiov, bytes_done, cipher_data, cur_bytes);
 494
 495         if (qcrypto_block_encrypt(crypto->block, offset + bytes_done,
 496                                   cipher_data, cur_bytes, NULL) < 0) {
 497             ret = -EIO;
 498             goto cleanup;
 499         }
 500
 501         qemu_iovec_reset(&hd_qiov);
 502         qemu_iovec_add(&hd_qiov, cipher_data, cur_bytes);
 503
 504         ret = bdrv_co_pwritev(bs->file, payload_offset + offset + bytes_done,
 505                               cur_bytes, &hd_qiov, flags);
 506         if (ret < 0) {
 507             goto cleanup;
 508         }
 509
 510         bytes -= cur_bytes;
 511         bytes_done += cur_bytes;
 512     }
 513
 514  cleanup:
 515     qemu_iovec_destroy(&hd_qiov);
 516     qemu_vfree(cipher_data);
 517
 518     return ret;
 519 }
 520
 521 static void block_crypto_refresh_limits(BlockDriverState *bs, Error **errp)
 522 {
 523     BlockCrypto *crypto = bs->opaque;
 524     uint64_t sector_size = qcrypto_block_get_sector_size(crypto->block);
 525     bs->bl.request_alignment = sector_size; /* No sub-sector I/O */
 526 }
 527
 528
 529 static int64_t block_crypto_getlength(BlockDriverState *bs)
 530 {
 531     BlockCrypto *crypto = bs->opaque;
 532     int64_t len = bdrv_getlength(bs->file->bs);
 533
 534     uint64_t offset = qcrypto_block_get_payload_offset(crypto->block);
 535     assert(offset < INT64_MAX);
 536
 537     if (offset > len) {
 538         return -EIO;
 539     }
 540
 541     len -= offset;
 542
 543     return len;
 544 }
 545
 546
 547 static int block_crypto_probe_luks(const uint8_t *buf,
 548                                    int buf_size,
 549                                    const char *filename) {
 550     return block_crypto_probe_generic(Q_CRYPTO_BLOCK_FORMAT_LUKS,
 551                                       buf, buf_size, filename);
 552 }
 553
 554 static int block_crypto_open_luks(BlockDriverState *bs,
 555                                   QDict *options,
 556                                   int flags,
 557                                   Error **errp)
 558 {
 559     return block_crypto_open_generic(Q_CRYPTO_BLOCK_FORMAT_LUKS,
 560                                      &block_crypto_runtime_opts_luks,
 561                                      bs, options, flags, errp);
 562 }
 563
 564 static int coroutine_fn
 565 block_crypto_co_create_luks(BlockdevCreateOptions *create_options, Error **errp)
 566 {
 567     BlockdevCreateOptionsLUKS *luks_opts;
 568     BlockDriverState *bs = NULL;
 569     QCryptoBlockCreateOptions create_opts;
 570     int ret;
 571
 572     assert(create_options->driver == BLOCKDEV_DRIVER_LUKS);
 573     luks_opts = &create_options->u.luks;
 574
 575     bs = bdrv_open_blockdev_ref(luks_opts->file, errp);
 576     if (bs == NULL) {
 577         return -EIO;
 578     }
 579
 580     create_opts = (QCryptoBlockCreateOptions) {
 581         .format = Q_CRYPTO_BLOCK_FORMAT_LUKS,
 582         .u.luks = *qapi_BlockdevCreateOptionsLUKS_base(luks_opts),
 583     };
 584
 585     ret = block_crypto_co_create_generic(bs, luks_opts->size, &create_opts,
 586                                          errp);
 587     if (ret < 0) {
 588         goto fail;
 589     }
 590
 591     ret = 0;
 592 fail:
 593     bdrv_unref(bs);
 594     return ret;
 595 }
 596
 597 static int coroutine_fn block_crypto_co_create_opts_luks(const char *filename,
 598                                                          QemuOpts *opts,
 599                                                          Error **errp)
 600 {
 601     QCryptoBlockCreateOptions *create_opts = NULL;
 602     BlockDriverState *bs = NULL;
 603     QDict *cryptoopts;
 604     int64_t size;
 605     int ret;
 606
 607     /* Parse options */
 608     size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0);
 609
 610     cryptoopts = qemu_opts_to_qdict_filtered(opts, NULL,
 611                                              &block_crypto_create_opts_luks,
 612                                              true);
 613
 614     create_opts = block_crypto_create_opts_init(Q_CRYPTO_BLOCK_FORMAT_LUKS,
 615                                                 cryptoopts, errp);
 616     if (!create_opts) {
 617         ret = -EINVAL;
 618         goto fail;
 619     }
 620
 621     /* Create protocol layer */
 622     ret = bdrv_create_file(filename, opts, errp);
 623     if (ret < 0) {
 624         return ret;
 625     }
 626
 627     bs = bdrv_open(filename, NULL, NULL,
 628                    BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp);
 629     if (!bs) {
 630         ret = -EINVAL;
 631         goto fail;
 632     }
 633
 634     /* Create format layer */
 635     ret = block_crypto_co_create_generic(bs, size, create_opts, errp);
 636     if (ret < 0) {
 637         goto fail;
 638     }
 639
 640     ret = 0;
 641 fail:
 642     bdrv_unref(bs);
 643     qapi_free_QCryptoBlockCreateOptions(create_opts);
 644     qobject_unref(cryptoopts);
 645     return ret;
 646 }
 647
 648 static int block_crypto_get_info_luks(BlockDriverState *bs,
 649                                       BlockDriverInfo *bdi)
 650 {
 651     BlockDriverInfo subbdi;
 652     int ret;
 653
 654     ret = bdrv_get_info(bs->file->bs, &subbdi);
 655     if (ret != 0) {
 656         return ret;
 657     }
 658
 659     bdi->unallocated_blocks_are_zero = false;
 660     bdi->cluster_size = subbdi.cluster_size;
 661
 662     return 0;
 663 }
 664
 665 static ImageInfoSpecific *
 666 block_crypto_get_specific_info_luks(BlockDriverState *bs)
 667 {
 668     BlockCrypto *crypto = bs->opaque;
 669     ImageInfoSpecific *spec_info;
 670     QCryptoBlockInfo *info;
 671
 672     info = qcrypto_block_get_info(crypto->block, NULL);
 673     if (!info) {
 674         return NULL;
 675     }
 676     if (info->format != Q_CRYPTO_BLOCK_FORMAT_LUKS) {
 677         qapi_free_QCryptoBlockInfo(info);
 678         return NULL;
 679     }
 680
 681     spec_info = g_new(ImageInfoSpecific, 1);
 682     spec_info->type = IMAGE_INFO_SPECIFIC_KIND_LUKS;
 683     spec_info->u.luks.data = g_new(QCryptoBlockInfoLUKS, 1);
 684     *spec_info->u.luks.data = info->u.luks;
 685
 686     /* Blank out pointers we've just stolen to avoid double free */
 687     memset(&info->u.luks, 0, sizeof(info->u.luks));
 688
 689     qapi_free_QCryptoBlockInfo(info);
 690
 691     return spec_info;
 692 }
 693
 694 BlockDriver bdrv_crypto_luks = {
 695     .format_name        = "luks",
 696     .instance_size      = sizeof(BlockCrypto),
 697     .bdrv_probe         = block_crypto_probe_luks,
 698     .bdrv_open          = block_crypto_open_luks,
 699     .bdrv_close         = block_crypto_close,
 700     .bdrv_child_perm    = bdrv_format_default_perms,
 701     .bdrv_co_create     = block_crypto_co_create_luks,
 702     .bdrv_co_create_opts = block_crypto_co_create_opts_luks,
 703     .bdrv_truncate      = block_crypto_truncate,
 704     .create_opts        = &block_crypto_create_opts_luks,
 705
 706     .bdrv_reopen_prepare = block_crypto_reopen_prepare,
 707     .bdrv_refresh_limits = block_crypto_refresh_limits,
 708     .bdrv_co_preadv     = block_crypto_co_preadv,
 709     .bdrv_co_pwritev    = block_crypto_co_pwritev,
 710     .bdrv_getlength     = block_crypto_getlength,
 711     .bdrv_get_info      = block_crypto_get_info_luks,
 712     .bdrv_get_specific_info = block_crypto_get_specific_info_luks,
 713 };
 714
 715 static void block_crypto_init(void)
 716 {
 717     bdrv_register(&bdrv_crypto_luks);
 718 }
 719
 720 block_init(block_crypto_init);