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block: remove all encryption handling APIs
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CommitLineData
78368575
DB
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 "sysemu/block-backend.h"
25#include "crypto/block.h"
26#include "qapi/opts-visitor.h"
306a06e5 27#include "qapi/qobject-input-visitor.h"
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DB
28#include "qapi-visit.h"
29#include "qapi/error.h"
306a06e5 30#include "block/crypto.h"
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31
32typedef struct BlockCrypto BlockCrypto;
33
34struct BlockCrypto {
35 QCryptoBlock *block;
36};
37
38
39static int block_crypto_probe_generic(QCryptoBlockFormat format,
40 const uint8_t *buf,
41 int buf_size,
42 const char *filename)
43{
44 if (qcrypto_block_has_format(format, buf, buf_size)) {
45 return 100;
46 } else {
47 return 0;
48 }
49}
50
51
52static ssize_t block_crypto_read_func(QCryptoBlock *block,
53 size_t offset,
54 uint8_t *buf,
55 size_t buflen,
e4a3507e 56 void *opaque,
37509233 57 Error **errp)
78368575
DB
58{
59 BlockDriverState *bs = opaque;
60 ssize_t ret;
61
cf2ab8fc 62 ret = bdrv_pread(bs->file, offset, buf, buflen);
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DB
63 if (ret < 0) {
64 error_setg_errno(errp, -ret, "Could not read encryption header");
65 return ret;
66 }
67 return ret;
68}
69
70
71struct BlockCryptoCreateData {
72 const char *filename;
73 QemuOpts *opts;
74 BlockBackend *blk;
75 uint64_t size;
76};
77
78
79static ssize_t block_crypto_write_func(QCryptoBlock *block,
80 size_t offset,
81 const uint8_t *buf,
82 size_t buflen,
e4a3507e 83 void *opaque,
37509233 84 Error **errp)
78368575
DB
85{
86 struct BlockCryptoCreateData *data = opaque;
87 ssize_t ret;
88
8341f00d 89 ret = blk_pwrite(data->blk, offset, buf, buflen, 0);
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DB
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
98static ssize_t block_crypto_init_func(QCryptoBlock *block,
99 size_t headerlen,
e4a3507e 100 void *opaque,
37509233 101 Error **errp)
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DB
102{
103 struct BlockCryptoCreateData *data = opaque;
104 int ret;
105
106 /* User provided size should reflect amount of space made
107 * available to the guest, so we must take account of that
108 * which will be used by the crypto header
109 */
110 data->size += headerlen;
111
112 qemu_opt_set_number(data->opts, BLOCK_OPT_SIZE, data->size, &error_abort);
113 ret = bdrv_create_file(data->filename, data->opts, errp);
114 if (ret < 0) {
115 return -1;
116 }
117
118 data->blk = blk_new_open(data->filename, NULL, NULL,
72e775c7 119 BDRV_O_RDWR | BDRV_O_PROTOCOL, errp);
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120 if (!data->blk) {
121 return -1;
122 }
123
124 return 0;
125}
126
127
128static QemuOptsList block_crypto_runtime_opts_luks = {
129 .name = "crypto",
130 .head = QTAILQ_HEAD_INITIALIZER(block_crypto_runtime_opts_luks.head),
131 .desc = {
4a47f854 132 BLOCK_CRYPTO_OPT_DEF_LUKS_KEY_SECRET(""),
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133 { /* end of list */ }
134 },
135};
136
137
138static QemuOptsList block_crypto_create_opts_luks = {
139 .name = "crypto",
140 .head = QTAILQ_HEAD_INITIALIZER(block_crypto_create_opts_luks.head),
141 .desc = {
142 {
143 .name = BLOCK_OPT_SIZE,
144 .type = QEMU_OPT_SIZE,
145 .help = "Virtual disk size"
146 },
4a47f854
DB
147 BLOCK_CRYPTO_OPT_DEF_LUKS_KEY_SECRET(""),
148 BLOCK_CRYPTO_OPT_DEF_LUKS_CIPHER_ALG(""),
149 BLOCK_CRYPTO_OPT_DEF_LUKS_CIPHER_MODE(""),
150 BLOCK_CRYPTO_OPT_DEF_LUKS_IVGEN_ALG(""),
151 BLOCK_CRYPTO_OPT_DEF_LUKS_IVGEN_HASH_ALG(""),
152 BLOCK_CRYPTO_OPT_DEF_LUKS_HASH_ALG(""),
153 BLOCK_CRYPTO_OPT_DEF_LUKS_ITER_TIME(""),
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154 { /* end of list */ }
155 },
156};
157
158
306a06e5 159QCryptoBlockOpenOptions *
78368575 160block_crypto_open_opts_init(QCryptoBlockFormat format,
306a06e5 161 QDict *opts,
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162 Error **errp)
163{
09204eac 164 Visitor *v;
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165 QCryptoBlockOpenOptions *ret = NULL;
166 Error *local_err = NULL;
167
168 ret = g_new0(QCryptoBlockOpenOptions, 1);
169 ret->format = format;
170
306a06e5 171 v = qobject_input_visitor_new_keyval(QOBJECT(opts));
78368575 172
09204eac 173 visit_start_struct(v, NULL, NULL, 0, &local_err);
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DB
174 if (local_err) {
175 goto out;
176 }
177
178 switch (format) {
179 case Q_CRYPTO_BLOCK_FORMAT_LUKS:
180 visit_type_QCryptoBlockOptionsLUKS_members(
09204eac 181 v, &ret->u.luks, &local_err);
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182 break;
183
d85f4222
DB
184 case Q_CRYPTO_BLOCK_FORMAT_QCOW:
185 visit_type_QCryptoBlockOptionsQCow_members(
186 v, &ret->u.qcow, &local_err);
187 break;
188
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DB
189 default:
190 error_setg(&local_err, "Unsupported block format %d", format);
191 break;
192 }
15c2f669 193 if (!local_err) {
09204eac 194 visit_check_struct(v, &local_err);
15c2f669 195 }
78368575 196
09204eac 197 visit_end_struct(v, NULL);
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198
199 out:
200 if (local_err) {
201 error_propagate(errp, local_err);
202 qapi_free_QCryptoBlockOpenOptions(ret);
203 ret = NULL;
204 }
09204eac 205 visit_free(v);
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206 return ret;
207}
208
209
306a06e5 210QCryptoBlockCreateOptions *
78368575 211block_crypto_create_opts_init(QCryptoBlockFormat format,
306a06e5 212 QDict *opts,
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213 Error **errp)
214{
09204eac 215 Visitor *v;
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216 QCryptoBlockCreateOptions *ret = NULL;
217 Error *local_err = NULL;
218
219 ret = g_new0(QCryptoBlockCreateOptions, 1);
220 ret->format = format;
221
306a06e5 222 v = qobject_input_visitor_new_keyval(QOBJECT(opts));
78368575 223
09204eac 224 visit_start_struct(v, NULL, NULL, 0, &local_err);
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225 if (local_err) {
226 goto out;
227 }
228
229 switch (format) {
230 case Q_CRYPTO_BLOCK_FORMAT_LUKS:
231 visit_type_QCryptoBlockCreateOptionsLUKS_members(
09204eac 232 v, &ret->u.luks, &local_err);
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233 break;
234
d85f4222
DB
235 case Q_CRYPTO_BLOCK_FORMAT_QCOW:
236 visit_type_QCryptoBlockOptionsQCow_members(
237 v, &ret->u.qcow, &local_err);
238 break;
239
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240 default:
241 error_setg(&local_err, "Unsupported block format %d", format);
242 break;
243 }
15c2f669 244 if (!local_err) {
09204eac 245 visit_check_struct(v, &local_err);
15c2f669 246 }
78368575 247
09204eac 248 visit_end_struct(v, NULL);
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DB
249
250 out:
251 if (local_err) {
252 error_propagate(errp, local_err);
253 qapi_free_QCryptoBlockCreateOptions(ret);
254 ret = NULL;
255 }
09204eac 256 visit_free(v);
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257 return ret;
258}
259
260
261static int block_crypto_open_generic(QCryptoBlockFormat format,
262 QemuOptsList *opts_spec,
263 BlockDriverState *bs,
264 QDict *options,
265 int flags,
266 Error **errp)
267{
268 BlockCrypto *crypto = bs->opaque;
269 QemuOpts *opts = NULL;
270 Error *local_err = NULL;
271 int ret = -EINVAL;
272 QCryptoBlockOpenOptions *open_opts = NULL;
273 unsigned int cflags = 0;
306a06e5 274 QDict *cryptoopts = NULL;
78368575 275
4e4bf5c4
KW
276 bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
277 false, errp);
278 if (!bs->file) {
279 return -EINVAL;
280 }
281
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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
306a06e5
DB
289 cryptoopts = qemu_opts_to_qdict(opts, NULL);
290
291 open_opts = block_crypto_open_opts_init(format, cryptoopts, errp);
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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,
300 block_crypto_read_func,
301 bs,
302 cflags,
303 errp);
304
305 if (!crypto->block) {
306 ret = -EIO;
307 goto cleanup;
308 }
309
54115412 310 bs->encrypted = true;
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311
312 ret = 0;
313 cleanup:
306a06e5 314 QDECREF(cryptoopts);
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315 qapi_free_QCryptoBlockOpenOptions(open_opts);
316 return ret;
317}
318
319
320static int block_crypto_create_generic(QCryptoBlockFormat format,
321 const char *filename,
322 QemuOpts *opts,
323 Error **errp)
324{
325 int ret = -EINVAL;
326 QCryptoBlockCreateOptions *create_opts = NULL;
327 QCryptoBlock *crypto = NULL;
328 struct BlockCryptoCreateData data = {
329 .size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
330 BDRV_SECTOR_SIZE),
331 .opts = opts,
332 .filename = filename,
333 };
306a06e5
DB
334 QDict *cryptoopts;
335
336 cryptoopts = qemu_opts_to_qdict(opts, NULL);
78368575 337
306a06e5 338 create_opts = block_crypto_create_opts_init(format, cryptoopts, errp);
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DB
339 if (!create_opts) {
340 return -1;
341 }
342
343 crypto = qcrypto_block_create(create_opts,
344 block_crypto_init_func,
345 block_crypto_write_func,
346 &data,
347 errp);
348
349 if (!crypto) {
350 ret = -EIO;
351 goto cleanup;
352 }
353
354 ret = 0;
355 cleanup:
306a06e5 356 QDECREF(cryptoopts);
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DB
357 qcrypto_block_free(crypto);
358 blk_unref(data.blk);
359 qapi_free_QCryptoBlockCreateOptions(create_opts);
360 return ret;
361}
362
4bff28b8
HR
363static int block_crypto_truncate(BlockDriverState *bs, int64_t offset,
364 Error **errp)
78368575
DB
365{
366 BlockCrypto *crypto = bs->opaque;
367 size_t payload_offset =
368 qcrypto_block_get_payload_offset(crypto->block);
369
370 offset += payload_offset;
371
4bff28b8 372 return bdrv_truncate(bs->file, offset, errp);
78368575
DB
373}
374
375static void block_crypto_close(BlockDriverState *bs)
376{
377 BlockCrypto *crypto = bs->opaque;
378 qcrypto_block_free(crypto->block);
379}
380
381
382#define BLOCK_CRYPTO_MAX_SECTORS 32
383
384static coroutine_fn int
385block_crypto_co_readv(BlockDriverState *bs, int64_t sector_num,
386 int remaining_sectors, QEMUIOVector *qiov)
387{
388 BlockCrypto *crypto = bs->opaque;
389 int cur_nr_sectors; /* number of sectors in current iteration */
390 uint64_t bytes_done = 0;
391 uint8_t *cipher_data = NULL;
392 QEMUIOVector hd_qiov;
393 int ret = 0;
394 size_t payload_offset =
395 qcrypto_block_get_payload_offset(crypto->block) / 512;
396
397 qemu_iovec_init(&hd_qiov, qiov->niov);
398
399 /* Bounce buffer so we have a linear mem region for
400 * entire sector. XXX optimize so we avoid bounce
401 * buffer in case that qiov->niov == 1
402 */
403 cipher_data =
404 qemu_try_blockalign(bs->file->bs, MIN(BLOCK_CRYPTO_MAX_SECTORS * 512,
405 qiov->size));
406 if (cipher_data == NULL) {
407 ret = -ENOMEM;
408 goto cleanup;
409 }
410
411 while (remaining_sectors) {
412 cur_nr_sectors = remaining_sectors;
413
414 if (cur_nr_sectors > BLOCK_CRYPTO_MAX_SECTORS) {
415 cur_nr_sectors = BLOCK_CRYPTO_MAX_SECTORS;
416 }
417
418 qemu_iovec_reset(&hd_qiov);
419 qemu_iovec_add(&hd_qiov, cipher_data, cur_nr_sectors * 512);
420
28b04a8f 421 ret = bdrv_co_readv(bs->file,
78368575
DB
422 payload_offset + sector_num,
423 cur_nr_sectors, &hd_qiov);
424 if (ret < 0) {
425 goto cleanup;
426 }
427
428 if (qcrypto_block_decrypt(crypto->block,
429 sector_num,
430 cipher_data, cur_nr_sectors * 512,
431 NULL) < 0) {
432 ret = -EIO;
433 goto cleanup;
434 }
435
436 qemu_iovec_from_buf(qiov, bytes_done,
437 cipher_data, cur_nr_sectors * 512);
438
439 remaining_sectors -= cur_nr_sectors;
440 sector_num += cur_nr_sectors;
441 bytes_done += cur_nr_sectors * 512;
442 }
443
444 cleanup:
445 qemu_iovec_destroy(&hd_qiov);
446 qemu_vfree(cipher_data);
447
448 return ret;
449}
450
451
452static coroutine_fn int
453block_crypto_co_writev(BlockDriverState *bs, int64_t sector_num,
454 int remaining_sectors, QEMUIOVector *qiov)
455{
456 BlockCrypto *crypto = bs->opaque;
457 int cur_nr_sectors; /* number of sectors in current iteration */
458 uint64_t bytes_done = 0;
459 uint8_t *cipher_data = NULL;
460 QEMUIOVector hd_qiov;
461 int ret = 0;
462 size_t payload_offset =
463 qcrypto_block_get_payload_offset(crypto->block) / 512;
464
465 qemu_iovec_init(&hd_qiov, qiov->niov);
466
467 /* Bounce buffer so we have a linear mem region for
468 * entire sector. XXX optimize so we avoid bounce
469 * buffer in case that qiov->niov == 1
470 */
471 cipher_data =
472 qemu_try_blockalign(bs->file->bs, MIN(BLOCK_CRYPTO_MAX_SECTORS * 512,
473 qiov->size));
474 if (cipher_data == NULL) {
475 ret = -ENOMEM;
476 goto cleanup;
477 }
478
479 while (remaining_sectors) {
480 cur_nr_sectors = remaining_sectors;
481
482 if (cur_nr_sectors > BLOCK_CRYPTO_MAX_SECTORS) {
483 cur_nr_sectors = BLOCK_CRYPTO_MAX_SECTORS;
484 }
485
486 qemu_iovec_to_buf(qiov, bytes_done,
487 cipher_data, cur_nr_sectors * 512);
488
489 if (qcrypto_block_encrypt(crypto->block,
490 sector_num,
491 cipher_data, cur_nr_sectors * 512,
492 NULL) < 0) {
493 ret = -EIO;
494 goto cleanup;
495 }
496
497 qemu_iovec_reset(&hd_qiov);
498 qemu_iovec_add(&hd_qiov, cipher_data, cur_nr_sectors * 512);
499
25ec177d 500 ret = bdrv_co_writev(bs->file,
78368575
DB
501 payload_offset + sector_num,
502 cur_nr_sectors, &hd_qiov);
503 if (ret < 0) {
504 goto cleanup;
505 }
506
507 remaining_sectors -= cur_nr_sectors;
508 sector_num += cur_nr_sectors;
509 bytes_done += cur_nr_sectors * 512;
510 }
511
512 cleanup:
513 qemu_iovec_destroy(&hd_qiov);
514 qemu_vfree(cipher_data);
515
516 return ret;
517}
518
519
520static int64_t block_crypto_getlength(BlockDriverState *bs)
521{
522 BlockCrypto *crypto = bs->opaque;
523 int64_t len = bdrv_getlength(bs->file->bs);
524
525 ssize_t offset = qcrypto_block_get_payload_offset(crypto->block);
526
527 len -= offset;
528
529 return len;
530}
531
532
533static int block_crypto_probe_luks(const uint8_t *buf,
534 int buf_size,
535 const char *filename) {
536 return block_crypto_probe_generic(Q_CRYPTO_BLOCK_FORMAT_LUKS,
537 buf, buf_size, filename);
538}
539
540static int block_crypto_open_luks(BlockDriverState *bs,
541 QDict *options,
542 int flags,
543 Error **errp)
544{
545 return block_crypto_open_generic(Q_CRYPTO_BLOCK_FORMAT_LUKS,
546 &block_crypto_runtime_opts_luks,
547 bs, options, flags, errp);
548}
549
550static int block_crypto_create_luks(const char *filename,
551 QemuOpts *opts,
552 Error **errp)
553{
554 return block_crypto_create_generic(Q_CRYPTO_BLOCK_FORMAT_LUKS,
555 filename, opts, errp);
556}
557
c7c4cf49
DB
558static int block_crypto_get_info_luks(BlockDriverState *bs,
559 BlockDriverInfo *bdi)
560{
561 BlockDriverInfo subbdi;
562 int ret;
563
564 ret = bdrv_get_info(bs->file->bs, &subbdi);
565 if (ret != 0) {
566 return ret;
567 }
568
569 bdi->unallocated_blocks_are_zero = false;
570 bdi->can_write_zeroes_with_unmap = false;
571 bdi->cluster_size = subbdi.cluster_size;
572
573 return 0;
574}
575
576static ImageInfoSpecific *
577block_crypto_get_specific_info_luks(BlockDriverState *bs)
578{
579 BlockCrypto *crypto = bs->opaque;
580 ImageInfoSpecific *spec_info;
581 QCryptoBlockInfo *info;
582
583 info = qcrypto_block_get_info(crypto->block, NULL);
584 if (!info) {
585 return NULL;
586 }
587 if (info->format != Q_CRYPTO_BLOCK_FORMAT_LUKS) {
588 qapi_free_QCryptoBlockInfo(info);
589 return NULL;
590 }
591
592 spec_info = g_new(ImageInfoSpecific, 1);
593 spec_info->type = IMAGE_INFO_SPECIFIC_KIND_LUKS;
594 spec_info->u.luks.data = g_new(QCryptoBlockInfoLUKS, 1);
595 *spec_info->u.luks.data = info->u.luks;
596
597 /* Blank out pointers we've just stolen to avoid double free */
598 memset(&info->u.luks, 0, sizeof(info->u.luks));
599
600 qapi_free_QCryptoBlockInfo(info);
601
602 return spec_info;
603}
604
78368575
DB
605BlockDriver bdrv_crypto_luks = {
606 .format_name = "luks",
607 .instance_size = sizeof(BlockCrypto),
608 .bdrv_probe = block_crypto_probe_luks,
609 .bdrv_open = block_crypto_open_luks,
610 .bdrv_close = block_crypto_close,
862f215f 611 .bdrv_child_perm = bdrv_format_default_perms,
78368575
DB
612 .bdrv_create = block_crypto_create_luks,
613 .bdrv_truncate = block_crypto_truncate,
614 .create_opts = &block_crypto_create_opts_luks,
615
616 .bdrv_co_readv = block_crypto_co_readv,
617 .bdrv_co_writev = block_crypto_co_writev,
618 .bdrv_getlength = block_crypto_getlength,
c7c4cf49
DB
619 .bdrv_get_info = block_crypto_get_info_luks,
620 .bdrv_get_specific_info = block_crypto_get_specific_info_luks,
78368575
DB
621};
622
623static void block_crypto_init(void)
624{
625 bdrv_register(&bdrv_crypto_luks);
626}
627
628block_init(block_crypto_init);