2 * QEMU Crypto block device encryption LUKS format
4 * Copyright (c) 2015-2016 Red Hat, Inc.
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 2.1 of the License, or (at your option) any later version.
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.
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/>.
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "qemu/bswap.h"
25 #include "block-luks.h"
26 #include "block-luks-priv.h"
28 #include "crypto/hash.h"
29 #include "crypto/afsplit.h"
30 #include "crypto/pbkdf.h"
31 #include "crypto/secret.h"
32 #include "crypto/random.h"
33 #include "qemu/uuid.h"
35 #include "qemu/bitmap.h"
38 * Reference for the LUKS format implemented here is
40 * docs/on-disk-format.pdf
42 * in 'cryptsetup' package source code
44 * This file implements the 1.2.1 specification, dated
48 typedef struct QCryptoBlockLUKS QCryptoBlockLUKS;
50 typedef struct QCryptoBlockLUKSNameMap QCryptoBlockLUKSNameMap;
51 struct QCryptoBlockLUKSNameMap {
56 typedef struct QCryptoBlockLUKSCipherSizeMap QCryptoBlockLUKSCipherSizeMap;
57 struct QCryptoBlockLUKSCipherSizeMap {
61 typedef struct QCryptoBlockLUKSCipherNameMap QCryptoBlockLUKSCipherNameMap;
62 struct QCryptoBlockLUKSCipherNameMap {
64 const QCryptoBlockLUKSCipherSizeMap *sizes;
68 static const QCryptoBlockLUKSCipherSizeMap
69 qcrypto_block_luks_cipher_size_map_aes[] = {
70 { 16, QCRYPTO_CIPHER_ALG_AES_128 },
71 { 24, QCRYPTO_CIPHER_ALG_AES_192 },
72 { 32, QCRYPTO_CIPHER_ALG_AES_256 },
76 static const QCryptoBlockLUKSCipherSizeMap
77 qcrypto_block_luks_cipher_size_map_cast5[] = {
78 { 16, QCRYPTO_CIPHER_ALG_CAST5_128 },
82 static const QCryptoBlockLUKSCipherSizeMap
83 qcrypto_block_luks_cipher_size_map_serpent[] = {
84 { 16, QCRYPTO_CIPHER_ALG_SERPENT_128 },
85 { 24, QCRYPTO_CIPHER_ALG_SERPENT_192 },
86 { 32, QCRYPTO_CIPHER_ALG_SERPENT_256 },
90 static const QCryptoBlockLUKSCipherSizeMap
91 qcrypto_block_luks_cipher_size_map_twofish[] = {
92 { 16, QCRYPTO_CIPHER_ALG_TWOFISH_128 },
93 { 24, QCRYPTO_CIPHER_ALG_TWOFISH_192 },
94 { 32, QCRYPTO_CIPHER_ALG_TWOFISH_256 },
98 static const QCryptoBlockLUKSCipherNameMap
99 qcrypto_block_luks_cipher_name_map[] = {
100 { "aes", qcrypto_block_luks_cipher_size_map_aes },
101 { "cast5", qcrypto_block_luks_cipher_size_map_cast5 },
102 { "serpent", qcrypto_block_luks_cipher_size_map_serpent },
103 { "twofish", qcrypto_block_luks_cipher_size_map_twofish },
106 QEMU_BUILD_BUG_ON(sizeof(struct QCryptoBlockLUKSKeySlot) != 48);
107 QEMU_BUILD_BUG_ON(sizeof(struct QCryptoBlockLUKSHeader) != 592);
110 struct QCryptoBlockLUKS {
111 QCryptoBlockLUKSHeader header;
113 /* Main encryption algorithm used for encryption*/
114 QCryptoCipherAlgorithm cipher_alg;
116 /* Mode of encryption for the selected encryption algorithm */
117 QCryptoCipherMode cipher_mode;
119 /* Initialization vector generation algorithm */
120 QCryptoIVGenAlgorithm ivgen_alg;
122 /* Hash algorithm used for IV generation*/
123 QCryptoHashAlgorithm ivgen_hash_alg;
126 * Encryption algorithm used for IV generation.
127 * Usually the same as main encryption algorithm
129 QCryptoCipherAlgorithm ivgen_cipher_alg;
131 /* Hash algorithm used in pbkdf2 function */
132 QCryptoHashAlgorithm hash_alg;
134 /* Name of the secret that was used to open the image */
139 static int qcrypto_block_luks_cipher_name_lookup(const char *name,
140 QCryptoCipherMode mode,
144 const QCryptoBlockLUKSCipherNameMap *map =
145 qcrypto_block_luks_cipher_name_map;
146 size_t maplen = G_N_ELEMENTS(qcrypto_block_luks_cipher_name_map);
149 if (mode == QCRYPTO_CIPHER_MODE_XTS) {
153 for (i = 0; i < maplen; i++) {
154 if (!g_str_equal(map[i].name, name)) {
157 for (j = 0; j < map[i].sizes[j].key_bytes; j++) {
158 if (map[i].sizes[j].key_bytes == key_bytes) {
159 return map[i].sizes[j].id;
164 error_setg(errp, "Algorithm '%s' with key size %d bytes not supported",
170 qcrypto_block_luks_cipher_alg_lookup(QCryptoCipherAlgorithm alg,
173 const QCryptoBlockLUKSCipherNameMap *map =
174 qcrypto_block_luks_cipher_name_map;
175 size_t maplen = G_N_ELEMENTS(qcrypto_block_luks_cipher_name_map);
177 for (i = 0; i < maplen; i++) {
178 for (j = 0; j < map[i].sizes[j].key_bytes; j++) {
179 if (map[i].sizes[j].id == alg) {
185 error_setg(errp, "Algorithm '%s' not supported",
186 QCryptoCipherAlgorithm_str(alg));
190 /* XXX replace with qapi_enum_parse() in future, when we can
191 * make that function emit a more friendly error message */
192 static int qcrypto_block_luks_name_lookup(const char *name,
193 const QEnumLookup *map,
197 int ret = qapi_enum_parse(map, name, -1, NULL);
200 error_setg(errp, "%s '%s' not supported", type, name);
206 #define qcrypto_block_luks_cipher_mode_lookup(name, errp) \
207 qcrypto_block_luks_name_lookup(name, \
208 &QCryptoCipherMode_lookup, \
212 #define qcrypto_block_luks_hash_name_lookup(name, errp) \
213 qcrypto_block_luks_name_lookup(name, \
214 &QCryptoHashAlgorithm_lookup, \
218 #define qcrypto_block_luks_ivgen_name_lookup(name, errp) \
219 qcrypto_block_luks_name_lookup(name, \
220 &QCryptoIVGenAlgorithm_lookup, \
226 qcrypto_block_luks_has_format(const uint8_t *buf,
229 const QCryptoBlockLUKSHeader *luks_header = (const void *)buf;
231 if (buf_size >= offsetof(QCryptoBlockLUKSHeader, cipher_name) &&
232 memcmp(luks_header->magic, qcrypto_block_luks_magic,
233 QCRYPTO_BLOCK_LUKS_MAGIC_LEN) == 0 &&
234 be16_to_cpu(luks_header->version) == QCRYPTO_BLOCK_LUKS_VERSION) {
243 * Deal with a quirk of dm-crypt usage of ESSIV.
245 * When calculating ESSIV IVs, the cipher length used by ESSIV
246 * may be different from the cipher length used for the block
247 * encryption, because dm-crypt uses the hash digest length
248 * as the key size. ie, if you have AES 128 as the block cipher
249 * and SHA 256 as ESSIV hash, then ESSIV will use AES 256 as
250 * the cipher since that gets a key length matching the digest
251 * size, not AES 128 with truncated digest as might be imagined
253 static QCryptoCipherAlgorithm
254 qcrypto_block_luks_essiv_cipher(QCryptoCipherAlgorithm cipher,
255 QCryptoHashAlgorithm hash,
258 size_t digestlen = qcrypto_hash_digest_len(hash);
259 size_t keylen = qcrypto_cipher_get_key_len(cipher);
260 if (digestlen == keylen) {
265 case QCRYPTO_CIPHER_ALG_AES_128:
266 case QCRYPTO_CIPHER_ALG_AES_192:
267 case QCRYPTO_CIPHER_ALG_AES_256:
268 if (digestlen == qcrypto_cipher_get_key_len(
269 QCRYPTO_CIPHER_ALG_AES_128)) {
270 return QCRYPTO_CIPHER_ALG_AES_128;
271 } else if (digestlen == qcrypto_cipher_get_key_len(
272 QCRYPTO_CIPHER_ALG_AES_192)) {
273 return QCRYPTO_CIPHER_ALG_AES_192;
274 } else if (digestlen == qcrypto_cipher_get_key_len(
275 QCRYPTO_CIPHER_ALG_AES_256)) {
276 return QCRYPTO_CIPHER_ALG_AES_256;
278 error_setg(errp, "No AES cipher with key size %zu available",
283 case QCRYPTO_CIPHER_ALG_SERPENT_128:
284 case QCRYPTO_CIPHER_ALG_SERPENT_192:
285 case QCRYPTO_CIPHER_ALG_SERPENT_256:
286 if (digestlen == qcrypto_cipher_get_key_len(
287 QCRYPTO_CIPHER_ALG_SERPENT_128)) {
288 return QCRYPTO_CIPHER_ALG_SERPENT_128;
289 } else if (digestlen == qcrypto_cipher_get_key_len(
290 QCRYPTO_CIPHER_ALG_SERPENT_192)) {
291 return QCRYPTO_CIPHER_ALG_SERPENT_192;
292 } else if (digestlen == qcrypto_cipher_get_key_len(
293 QCRYPTO_CIPHER_ALG_SERPENT_256)) {
294 return QCRYPTO_CIPHER_ALG_SERPENT_256;
296 error_setg(errp, "No Serpent cipher with key size %zu available",
301 case QCRYPTO_CIPHER_ALG_TWOFISH_128:
302 case QCRYPTO_CIPHER_ALG_TWOFISH_192:
303 case QCRYPTO_CIPHER_ALG_TWOFISH_256:
304 if (digestlen == qcrypto_cipher_get_key_len(
305 QCRYPTO_CIPHER_ALG_TWOFISH_128)) {
306 return QCRYPTO_CIPHER_ALG_TWOFISH_128;
307 } else if (digestlen == qcrypto_cipher_get_key_len(
308 QCRYPTO_CIPHER_ALG_TWOFISH_192)) {
309 return QCRYPTO_CIPHER_ALG_TWOFISH_192;
310 } else if (digestlen == qcrypto_cipher_get_key_len(
311 QCRYPTO_CIPHER_ALG_TWOFISH_256)) {
312 return QCRYPTO_CIPHER_ALG_TWOFISH_256;
314 error_setg(errp, "No Twofish cipher with key size %zu available",
320 error_setg(errp, "Cipher %s not supported with essiv",
321 QCryptoCipherAlgorithm_str(cipher));
327 * Returns number of sectors needed to store the key material
328 * given number of anti forensic stripes
331 qcrypto_block_luks_splitkeylen_sectors(const QCryptoBlockLUKS *luks,
332 unsigned int header_sectors,
333 unsigned int stripes)
336 * This calculation doesn't match that shown in the spec,
337 * but instead follows the cryptsetup implementation.
340 size_t splitkeylen = luks->header.master_key_len * stripes;
342 /* First align the key material size to block size*/
343 size_t splitkeylen_sectors =
344 DIV_ROUND_UP(splitkeylen, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE);
346 /* Then also align the key material size to the size of the header */
347 return ROUND_UP(splitkeylen_sectors, header_sectors);
352 qcrypto_block_luks_to_disk_endian(QCryptoBlockLUKSHeader *hdr)
357 * Everything on disk uses Big Endian (tm), so flip header fields
358 * before writing them
360 cpu_to_be16s(&hdr->version);
361 cpu_to_be32s(&hdr->payload_offset_sector);
362 cpu_to_be32s(&hdr->master_key_len);
363 cpu_to_be32s(&hdr->master_key_iterations);
365 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
366 cpu_to_be32s(&hdr->key_slots[i].active);
367 cpu_to_be32s(&hdr->key_slots[i].iterations);
368 cpu_to_be32s(&hdr->key_slots[i].key_offset_sector);
369 cpu_to_be32s(&hdr->key_slots[i].stripes);
374 qcrypto_block_luks_from_disk_endian(QCryptoBlockLUKSHeader *hdr)
379 * The header is always stored in big-endian format, so
380 * convert everything to native
382 be16_to_cpus(&hdr->version);
383 be32_to_cpus(&hdr->payload_offset_sector);
384 be32_to_cpus(&hdr->master_key_len);
385 be32_to_cpus(&hdr->master_key_iterations);
387 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
388 be32_to_cpus(&hdr->key_slots[i].active);
389 be32_to_cpus(&hdr->key_slots[i].iterations);
390 be32_to_cpus(&hdr->key_slots[i].key_offset_sector);
391 be32_to_cpus(&hdr->key_slots[i].stripes);
396 * Stores the main LUKS header, taking care of endianness
399 qcrypto_block_luks_store_header(QCryptoBlock *block,
400 QCryptoBlockWriteFunc writefunc,
404 const QCryptoBlockLUKS *luks = block->opaque;
405 Error *local_err = NULL;
406 g_autofree QCryptoBlockLUKSHeader *hdr_copy = NULL;
408 /* Create a copy of the header */
409 hdr_copy = g_new0(QCryptoBlockLUKSHeader, 1);
410 memcpy(hdr_copy, &luks->header, sizeof(QCryptoBlockLUKSHeader));
412 qcrypto_block_luks_to_disk_endian(hdr_copy);
414 /* Write out the partition header and key slot headers */
415 writefunc(block, 0, (const uint8_t *)hdr_copy, sizeof(*hdr_copy),
419 error_propagate(errp, local_err);
426 * Loads the main LUKS header, and byteswaps it to native endianness
427 * And run basic sanity checks on it
430 qcrypto_block_luks_load_header(QCryptoBlock *block,
431 QCryptoBlockReadFunc readfunc,
436 QCryptoBlockLUKS *luks = block->opaque;
439 * Read the entire LUKS header, minus the key material from
440 * the underlying device
442 rv = readfunc(block, 0,
443 (uint8_t *)&luks->header,
444 sizeof(luks->header),
451 qcrypto_block_luks_from_disk_endian(&luks->header);
457 * Does basic sanity checks on the LUKS header
460 qcrypto_block_luks_check_header(const QCryptoBlockLUKS *luks, Error **errp)
464 unsigned int header_sectors = QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
465 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
467 if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
468 QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
469 error_setg(errp, "Volume is not in LUKS format");
473 if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) {
474 error_setg(errp, "LUKS version %" PRIu32 " is not supported",
475 luks->header.version);
479 if (!memchr(luks->header.cipher_name, '\0',
480 sizeof(luks->header.cipher_name))) {
481 error_setg(errp, "LUKS header cipher name is not NUL terminated");
485 if (!memchr(luks->header.cipher_mode, '\0',
486 sizeof(luks->header.cipher_mode))) {
487 error_setg(errp, "LUKS header cipher mode is not NUL terminated");
491 if (!memchr(luks->header.hash_spec, '\0',
492 sizeof(luks->header.hash_spec))) {
493 error_setg(errp, "LUKS header hash spec is not NUL terminated");
497 if (luks->header.payload_offset_sector <
498 DIV_ROUND_UP(QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET,
499 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) {
500 error_setg(errp, "LUKS payload is overlapping with the header");
504 if (luks->header.master_key_iterations == 0) {
505 error_setg(errp, "LUKS key iteration count is zero");
509 /* Check all keyslots for corruption */
510 for (i = 0 ; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS ; i++) {
512 const QCryptoBlockLUKSKeySlot *slot1 = &luks->header.key_slots[i];
513 unsigned int start1 = slot1->key_offset_sector;
515 qcrypto_block_luks_splitkeylen_sectors(luks,
519 if (slot1->stripes != QCRYPTO_BLOCK_LUKS_STRIPES) {
520 error_setg(errp, "Keyslot %zu is corrupted (stripes %d != %d)",
521 i, slot1->stripes, QCRYPTO_BLOCK_LUKS_STRIPES);
525 if (slot1->active != QCRYPTO_BLOCK_LUKS_KEY_SLOT_DISABLED &&
526 slot1->active != QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED) {
528 "Keyslot %zu state (active/disable) is corrupted", i);
532 if (slot1->active == QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED &&
533 slot1->iterations == 0) {
534 error_setg(errp, "Keyslot %zu iteration count is zero", i);
538 if (start1 < DIV_ROUND_UP(QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET,
539 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE)) {
541 "Keyslot %zu is overlapping with the LUKS header",
546 if (start1 + len1 > luks->header.payload_offset_sector) {
548 "Keyslot %zu is overlapping with the encrypted payload",
553 for (j = i + 1 ; j < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS ; j++) {
554 const QCryptoBlockLUKSKeySlot *slot2 = &luks->header.key_slots[j];
555 unsigned int start2 = slot2->key_offset_sector;
557 qcrypto_block_luks_splitkeylen_sectors(luks,
561 if (start1 + len1 > start2 && start2 + len2 > start1) {
563 "Keyslots %zu and %zu are overlapping in the header",
574 * Parses the crypto parameters that are stored in the LUKS header
578 qcrypto_block_luks_parse_header(QCryptoBlockLUKS *luks, Error **errp)
580 g_autofree char *cipher_mode = g_strdup(luks->header.cipher_mode);
581 char *ivgen_name, *ivhash_name;
582 Error *local_err = NULL;
585 * The cipher_mode header contains a string that we have
586 * to further parse, of the format
588 * <cipher-mode>-<iv-generator>[:<iv-hash>]
590 * eg cbc-essiv:sha256, cbc-plain64
592 ivgen_name = strchr(cipher_mode, '-');
594 error_setg(errp, "Unexpected cipher mode string format '%s'",
595 luks->header.cipher_mode);
601 ivhash_name = strchr(ivgen_name, ':');
603 luks->ivgen_hash_alg = 0;
608 luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name,
611 error_propagate(errp, local_err);
616 luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode,
619 error_propagate(errp, local_err);
624 qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name,
626 luks->header.master_key_len,
629 error_propagate(errp, local_err);
634 qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec,
637 error_propagate(errp, local_err);
641 luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name,
644 error_propagate(errp, local_err);
648 if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
650 error_setg(errp, "Missing IV generator hash specification");
653 luks->ivgen_cipher_alg =
654 qcrypto_block_luks_essiv_cipher(luks->cipher_alg,
655 luks->ivgen_hash_alg,
658 error_propagate(errp, local_err);
664 * Note we parsed the ivhash_name earlier in the cipher_mode
665 * spec string even with plain/plain64 ivgens, but we
666 * will ignore it, since it is irrelevant for these ivgens.
667 * This is for compat with dm-crypt which will silently
668 * ignore hash names with these ivgens rather than report
669 * an error about the invalid usage
671 luks->ivgen_cipher_alg = luks->cipher_alg;
677 * Given a key slot, user password, and the master key,
678 * will store the encrypted master key there, and update the
679 * in-memory header. User must then write the in-memory header
682 * 0 if the keyslot was written successfully
683 * with the provided password
684 * -1 if a fatal error occurred while storing the key
687 qcrypto_block_luks_store_key(QCryptoBlock *block,
688 unsigned int slot_idx,
689 const char *password,
692 QCryptoBlockWriteFunc writefunc,
696 QCryptoBlockLUKS *luks = block->opaque;
697 QCryptoBlockLUKSKeySlot *slot;
698 g_autofree uint8_t *splitkey = NULL;
700 g_autofree uint8_t *slotkey = NULL;
701 g_autoptr(QCryptoCipher) cipher = NULL;
702 g_autoptr(QCryptoIVGen) ivgen = NULL;
703 Error *local_err = NULL;
707 assert(slot_idx < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
708 slot = &luks->header.key_slots[slot_idx];
709 splitkeylen = luks->header.master_key_len * slot->stripes;
711 if (qcrypto_random_bytes(slot->salt,
712 QCRYPTO_BLOCK_LUKS_SALT_LEN,
718 * Determine how many iterations are required to
719 * hash the user password while consuming 1 second of compute
722 iters = qcrypto_pbkdf2_count_iters(luks->hash_alg,
723 (uint8_t *)password, strlen(password),
725 QCRYPTO_BLOCK_LUKS_SALT_LEN,
726 luks->header.master_key_len,
729 error_propagate(errp, local_err);
733 if (iters > (ULLONG_MAX / iter_time)) {
734 error_setg_errno(errp, ERANGE,
735 "PBKDF iterations %llu too large to scale",
736 (unsigned long long)iters);
740 /* iter_time was in millis, but count_iters reported for secs */
741 iters = iters * iter_time / 1000;
743 if (iters > UINT32_MAX) {
744 error_setg_errno(errp, ERANGE,
745 "PBKDF iterations %llu larger than %u",
746 (unsigned long long)iters, UINT32_MAX);
751 MAX(iters, QCRYPTO_BLOCK_LUKS_MIN_SLOT_KEY_ITERS);
755 * Generate a key that we'll use to encrypt the master
756 * key, from the user's password
758 slotkey = g_new0(uint8_t, luks->header.master_key_len);
759 if (qcrypto_pbkdf2(luks->hash_alg,
760 (uint8_t *)password, strlen(password),
762 QCRYPTO_BLOCK_LUKS_SALT_LEN,
764 slotkey, luks->header.master_key_len,
771 * Setup the encryption objects needed to encrypt the
772 * master key material
774 cipher = qcrypto_cipher_new(luks->cipher_alg,
776 slotkey, luks->header.master_key_len,
782 ivgen = qcrypto_ivgen_new(luks->ivgen_alg,
783 luks->ivgen_cipher_alg,
784 luks->ivgen_hash_alg,
785 slotkey, luks->header.master_key_len,
792 * Before storing the master key, we need to vastly
793 * increase its size, as protection against forensic
796 splitkey = g_new0(uint8_t, splitkeylen);
798 if (qcrypto_afsplit_encode(luks->hash_alg,
799 luks->header.master_key_len,
808 * Now we encrypt the split master key with the key generated
809 * from the user's password, before storing it
811 if (qcrypto_block_cipher_encrypt_helper(cipher, block->niv, ivgen,
812 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
820 /* Write out the slot's master key material. */
822 slot->key_offset_sector *
823 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
824 splitkey, splitkeylen,
830 slot->active = QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED;
832 if (qcrypto_block_luks_store_header(block, writefunc, opaque, errp) < 0) {
840 memset(slotkey, 0, luks->header.master_key_len);
843 memset(splitkey, 0, splitkeylen);
849 * Given a key slot, and user password, this will attempt to unlock
850 * the master encryption key from the key slot.
853 * 0 if the key slot is disabled, or key could not be decrypted
854 * with the provided password
855 * 1 if the key slot is enabled, and key decrypted successfully
856 * with the provided password
857 * -1 if a fatal error occurred loading the key
860 qcrypto_block_luks_load_key(QCryptoBlock *block,
862 const char *password,
864 QCryptoBlockReadFunc readfunc,
868 QCryptoBlockLUKS *luks = block->opaque;
869 const QCryptoBlockLUKSKeySlot *slot;
870 g_autofree uint8_t *splitkey = NULL;
872 g_autofree uint8_t *possiblekey = NULL;
874 g_autoptr(QCryptoCipher) cipher = NULL;
875 uint8_t keydigest[QCRYPTO_BLOCK_LUKS_DIGEST_LEN];
876 g_autoptr(QCryptoIVGen) ivgen = NULL;
879 assert(slot_idx < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
880 slot = &luks->header.key_slots[slot_idx];
881 if (slot->active != QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED) {
885 splitkeylen = luks->header.master_key_len * slot->stripes;
886 splitkey = g_new0(uint8_t, splitkeylen);
887 possiblekey = g_new0(uint8_t, luks->header.master_key_len);
890 * The user password is used to generate a (possible)
891 * decryption key. This may or may not successfully
892 * decrypt the master key - we just blindly assume
893 * the key is correct and validate the results of
896 if (qcrypto_pbkdf2(luks->hash_alg,
897 (const uint8_t *)password, strlen(password),
898 slot->salt, QCRYPTO_BLOCK_LUKS_SALT_LEN,
900 possiblekey, luks->header.master_key_len,
906 * We need to read the master key material from the
907 * LUKS key material header. What we're reading is
908 * not the raw master key, but rather the data after
909 * it has been passed through AFSplit and the result
913 slot->key_offset_sector * QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
914 splitkey, splitkeylen,
922 /* Setup the cipher/ivgen that we'll use to try to decrypt
923 * the split master key material */
924 cipher = qcrypto_cipher_new(luks->cipher_alg,
927 luks->header.master_key_len,
933 niv = qcrypto_cipher_get_iv_len(luks->cipher_alg,
936 ivgen = qcrypto_ivgen_new(luks->ivgen_alg,
937 luks->ivgen_cipher_alg,
938 luks->ivgen_hash_alg,
940 luks->header.master_key_len,
948 * The master key needs to be decrypted in the same
949 * way that the block device payload will be decrypted
950 * later. In particular we'll be using the IV generator
951 * to reset the encryption cipher every time the master
952 * key crosses a sector boundary.
954 if (qcrypto_block_cipher_decrypt_helper(cipher,
957 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
966 * Now we've decrypted the split master key, join
967 * it back together to get the actual master key.
969 if (qcrypto_afsplit_decode(luks->hash_alg,
970 luks->header.master_key_len,
980 * We still don't know that the masterkey we got is valid,
981 * because we just blindly assumed the user's password
982 * was correct. This is where we now verify it. We are
983 * creating a hash of the master key using PBKDF and
984 * then comparing that to the hash stored in the key slot
987 if (qcrypto_pbkdf2(luks->hash_alg,
989 luks->header.master_key_len,
990 luks->header.master_key_salt,
991 QCRYPTO_BLOCK_LUKS_SALT_LEN,
992 luks->header.master_key_iterations,
994 G_N_ELEMENTS(keydigest),
999 if (memcmp(keydigest, luks->header.master_key_digest,
1000 QCRYPTO_BLOCK_LUKS_DIGEST_LEN) == 0) {
1001 /* Success, we got the right master key */
1005 /* Fail, user's password was not valid for this key slot,
1006 * tell caller to try another slot */
1012 * Given a user password, this will iterate over all key
1013 * slots and try to unlock each active key slot using the
1014 * password until it successfully obtains a master key.
1016 * Returns 0 if a key was loaded, -1 if no keys could be loaded
1019 qcrypto_block_luks_find_key(QCryptoBlock *block,
1020 const char *password,
1022 QCryptoBlockReadFunc readfunc,
1029 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1030 rv = qcrypto_block_luks_load_key(block,
1045 error_setg(errp, "Invalid password, cannot unlock any keyslot");
1051 * Returns true if a slot i is marked as active
1052 * (contains encrypted copy of the master key)
1055 qcrypto_block_luks_slot_active(const QCryptoBlockLUKS *luks,
1056 unsigned int slot_idx)
1060 assert(slot_idx < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
1061 val = luks->header.key_slots[slot_idx].active;
1062 return val == QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED;
1066 * Returns the number of slots that are marked as active
1067 * (slots that contain encrypted copy of the master key)
1070 qcrypto_block_luks_count_active_slots(const QCryptoBlockLUKS *luks)
1073 unsigned int ret = 0;
1075 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1076 if (qcrypto_block_luks_slot_active(luks, i)) {
1084 * Finds first key slot which is not active
1085 * Returns the key slot index, or -1 if it doesn't exist
1088 qcrypto_block_luks_find_free_keyslot(const QCryptoBlockLUKS *luks)
1092 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1093 if (!qcrypto_block_luks_slot_active(luks, i)) {
1101 * Erases an keyslot given its index
1103 * 0 if the keyslot was erased successfully
1104 * -1 if a error occurred while erasing the keyslot
1108 qcrypto_block_luks_erase_key(QCryptoBlock *block,
1109 unsigned int slot_idx,
1110 QCryptoBlockWriteFunc writefunc,
1114 QCryptoBlockLUKS *luks = block->opaque;
1115 QCryptoBlockLUKSKeySlot *slot;
1116 g_autofree uint8_t *garbagesplitkey = NULL;
1119 Error *local_err = NULL;
1122 assert(slot_idx < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
1123 slot = &luks->header.key_slots[slot_idx];
1125 splitkeylen = luks->header.master_key_len * slot->stripes;
1126 assert(splitkeylen > 0);
1128 garbagesplitkey = g_new0(uint8_t, splitkeylen);
1130 /* Reset the key slot header */
1131 memset(slot->salt, 0, QCRYPTO_BLOCK_LUKS_SALT_LEN);
1132 slot->iterations = 0;
1133 slot->active = QCRYPTO_BLOCK_LUKS_KEY_SLOT_DISABLED;
1135 ret = qcrypto_block_luks_store_header(block, writefunc,
1136 opaque, &local_err);
1139 error_propagate(errp, local_err);
1142 * Now try to erase the key material, even if the header
1145 for (i = 0; i < QCRYPTO_BLOCK_LUKS_ERASE_ITERATIONS; i++) {
1146 if (qcrypto_random_bytes(garbagesplitkey,
1147 splitkeylen, &local_err) < 0) {
1149 * If we failed to get the random data, still write
1150 * at least zeros to the key slot at least once
1152 error_propagate(errp, local_err);
1158 if (writefunc(block,
1159 slot->key_offset_sector * QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
1164 error_propagate(errp, local_err);
1172 qcrypto_block_luks_open(QCryptoBlock *block,
1173 QCryptoBlockOpenOptions *options,
1174 const char *optprefix,
1175 QCryptoBlockReadFunc readfunc,
1181 QCryptoBlockLUKS *luks = NULL;
1182 g_autofree uint8_t *masterkey = NULL;
1183 g_autofree char *password = NULL;
1185 if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
1186 if (!options->u.luks.key_secret) {
1187 error_setg(errp, "Parameter '%skey-secret' is required for cipher",
1188 optprefix ? optprefix : "");
1191 password = qcrypto_secret_lookup_as_utf8(
1192 options->u.luks.key_secret, errp);
1198 luks = g_new0(QCryptoBlockLUKS, 1);
1199 block->opaque = luks;
1200 luks->secret = g_strdup(options->u.luks.key_secret);
1202 if (qcrypto_block_luks_load_header(block, readfunc, opaque, errp) < 0) {
1206 if (qcrypto_block_luks_check_header(luks, errp) < 0) {
1210 if (qcrypto_block_luks_parse_header(luks, errp) < 0) {
1214 if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
1215 /* Try to find which key slot our password is valid for
1216 * and unlock the master key from that slot.
1219 masterkey = g_new0(uint8_t, luks->header.master_key_len);
1221 if (qcrypto_block_luks_find_key(block,
1229 /* We have a valid master key now, so can setup the
1230 * block device payload decryption objects
1232 block->kdfhash = luks->hash_alg;
1233 block->niv = qcrypto_cipher_get_iv_len(luks->cipher_alg,
1236 block->ivgen = qcrypto_ivgen_new(luks->ivgen_alg,
1237 luks->ivgen_cipher_alg,
1238 luks->ivgen_hash_alg,
1240 luks->header.master_key_len,
1242 if (!block->ivgen) {
1246 if (qcrypto_block_init_cipher(block,
1250 luks->header.master_key_len,
1257 block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
1258 block->payload_offset = luks->header.payload_offset_sector *
1264 qcrypto_block_free_cipher(block);
1265 qcrypto_ivgen_free(block->ivgen);
1266 g_free(luks->secret);
1273 qcrypto_block_luks_uuid_gen(uint8_t *uuidstr)
1276 qemu_uuid_generate(&uuid);
1277 qemu_uuid_unparse(&uuid, (char *)uuidstr);
1281 qcrypto_block_luks_create(QCryptoBlock *block,
1282 QCryptoBlockCreateOptions *options,
1283 const char *optprefix,
1284 QCryptoBlockInitFunc initfunc,
1285 QCryptoBlockWriteFunc writefunc,
1289 QCryptoBlockLUKS *luks;
1290 QCryptoBlockCreateOptionsLUKS luks_opts;
1291 Error *local_err = NULL;
1292 g_autofree uint8_t *masterkey = NULL;
1293 size_t header_sectors;
1294 size_t split_key_sectors;
1296 g_autofree char *password = NULL;
1297 const char *cipher_alg;
1298 const char *cipher_mode;
1299 const char *ivgen_alg;
1300 const char *ivgen_hash_alg = NULL;
1301 const char *hash_alg;
1302 g_autofree char *cipher_mode_spec = NULL;
1305 memcpy(&luks_opts, &options->u.luks, sizeof(luks_opts));
1306 if (!luks_opts.has_iter_time) {
1307 luks_opts.iter_time = QCRYPTO_BLOCK_LUKS_DEFAULT_ITER_TIME_MS;
1309 if (!luks_opts.has_cipher_alg) {
1310 luks_opts.cipher_alg = QCRYPTO_CIPHER_ALG_AES_256;
1312 if (!luks_opts.has_cipher_mode) {
1313 luks_opts.cipher_mode = QCRYPTO_CIPHER_MODE_XTS;
1315 if (!luks_opts.has_ivgen_alg) {
1316 luks_opts.ivgen_alg = QCRYPTO_IVGEN_ALG_PLAIN64;
1318 if (!luks_opts.has_hash_alg) {
1319 luks_opts.hash_alg = QCRYPTO_HASH_ALG_SHA256;
1321 if (luks_opts.ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
1322 if (!luks_opts.has_ivgen_hash_alg) {
1323 luks_opts.ivgen_hash_alg = QCRYPTO_HASH_ALG_SHA256;
1324 luks_opts.has_ivgen_hash_alg = true;
1328 luks = g_new0(QCryptoBlockLUKS, 1);
1329 block->opaque = luks;
1331 luks->cipher_alg = luks_opts.cipher_alg;
1332 luks->cipher_mode = luks_opts.cipher_mode;
1333 luks->ivgen_alg = luks_opts.ivgen_alg;
1334 luks->ivgen_hash_alg = luks_opts.ivgen_hash_alg;
1335 luks->hash_alg = luks_opts.hash_alg;
1338 /* Note we're allowing ivgen_hash_alg to be set even for
1339 * non-essiv iv generators that don't need a hash. It will
1340 * be silently ignored, for compatibility with dm-crypt */
1342 if (!options->u.luks.key_secret) {
1343 error_setg(errp, "Parameter '%skey-secret' is required for cipher",
1344 optprefix ? optprefix : "");
1347 luks->secret = g_strdup(options->u.luks.key_secret);
1349 password = qcrypto_secret_lookup_as_utf8(luks_opts.key_secret, errp);
1355 memcpy(luks->header.magic, qcrypto_block_luks_magic,
1356 QCRYPTO_BLOCK_LUKS_MAGIC_LEN);
1358 /* We populate the header in native endianness initially and
1359 * then convert everything to big endian just before writing
1362 luks->header.version = QCRYPTO_BLOCK_LUKS_VERSION;
1363 qcrypto_block_luks_uuid_gen(luks->header.uuid);
1365 cipher_alg = qcrypto_block_luks_cipher_alg_lookup(luks_opts.cipher_alg,
1371 cipher_mode = QCryptoCipherMode_str(luks_opts.cipher_mode);
1372 ivgen_alg = QCryptoIVGenAlgorithm_str(luks_opts.ivgen_alg);
1373 if (luks_opts.has_ivgen_hash_alg) {
1374 ivgen_hash_alg = QCryptoHashAlgorithm_str(luks_opts.ivgen_hash_alg);
1375 cipher_mode_spec = g_strdup_printf("%s-%s:%s", cipher_mode, ivgen_alg,
1378 cipher_mode_spec = g_strdup_printf("%s-%s", cipher_mode, ivgen_alg);
1380 hash_alg = QCryptoHashAlgorithm_str(luks_opts.hash_alg);
1383 if (strlen(cipher_alg) >= QCRYPTO_BLOCK_LUKS_CIPHER_NAME_LEN) {
1384 error_setg(errp, "Cipher name '%s' is too long for LUKS header",
1388 if (strlen(cipher_mode_spec) >= QCRYPTO_BLOCK_LUKS_CIPHER_MODE_LEN) {
1389 error_setg(errp, "Cipher mode '%s' is too long for LUKS header",
1393 if (strlen(hash_alg) >= QCRYPTO_BLOCK_LUKS_HASH_SPEC_LEN) {
1394 error_setg(errp, "Hash name '%s' is too long for LUKS header",
1399 if (luks_opts.ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
1400 luks->ivgen_cipher_alg =
1401 qcrypto_block_luks_essiv_cipher(luks_opts.cipher_alg,
1402 luks_opts.ivgen_hash_alg,
1405 error_propagate(errp, local_err);
1409 luks->ivgen_cipher_alg = luks_opts.cipher_alg;
1412 strcpy(luks->header.cipher_name, cipher_alg);
1413 strcpy(luks->header.cipher_mode, cipher_mode_spec);
1414 strcpy(luks->header.hash_spec, hash_alg);
1416 luks->header.master_key_len =
1417 qcrypto_cipher_get_key_len(luks_opts.cipher_alg);
1419 if (luks_opts.cipher_mode == QCRYPTO_CIPHER_MODE_XTS) {
1420 luks->header.master_key_len *= 2;
1423 /* Generate the salt used for hashing the master key
1426 if (qcrypto_random_bytes(luks->header.master_key_salt,
1427 QCRYPTO_BLOCK_LUKS_SALT_LEN,
1432 /* Generate random master key */
1433 masterkey = g_new0(uint8_t, luks->header.master_key_len);
1434 if (qcrypto_random_bytes(masterkey,
1435 luks->header.master_key_len, errp) < 0) {
1440 /* Setup the block device payload encryption objects */
1441 if (qcrypto_block_init_cipher(block, luks_opts.cipher_alg,
1442 luks_opts.cipher_mode, masterkey,
1443 luks->header.master_key_len, 1, errp) < 0) {
1447 block->kdfhash = luks_opts.hash_alg;
1448 block->niv = qcrypto_cipher_get_iv_len(luks_opts.cipher_alg,
1449 luks_opts.cipher_mode);
1450 block->ivgen = qcrypto_ivgen_new(luks_opts.ivgen_alg,
1451 luks->ivgen_cipher_alg,
1452 luks_opts.ivgen_hash_alg,
1453 masterkey, luks->header.master_key_len,
1456 if (!block->ivgen) {
1461 /* Determine how many iterations we need to hash the master
1462 * key, in order to have 1 second of compute time used
1464 iters = qcrypto_pbkdf2_count_iters(luks_opts.hash_alg,
1465 masterkey, luks->header.master_key_len,
1466 luks->header.master_key_salt,
1467 QCRYPTO_BLOCK_LUKS_SALT_LEN,
1468 QCRYPTO_BLOCK_LUKS_DIGEST_LEN,
1471 error_propagate(errp, local_err);
1475 if (iters > (ULLONG_MAX / luks_opts.iter_time)) {
1476 error_setg_errno(errp, ERANGE,
1477 "PBKDF iterations %llu too large to scale",
1478 (unsigned long long)iters);
1482 /* iter_time was in millis, but count_iters reported for secs */
1483 iters = iters * luks_opts.iter_time / 1000;
1485 /* Why /= 8 ? That matches cryptsetup, but there's no
1486 * explanation why they chose /= 8... Probably so that
1487 * if all 8 keyslots are active we only spend 1 second
1488 * in total time to check all keys */
1490 if (iters > UINT32_MAX) {
1491 error_setg_errno(errp, ERANGE,
1492 "PBKDF iterations %llu larger than %u",
1493 (unsigned long long)iters, UINT32_MAX);
1496 iters = MAX(iters, QCRYPTO_BLOCK_LUKS_MIN_MASTER_KEY_ITERS);
1497 luks->header.master_key_iterations = iters;
1499 /* Hash the master key, saving the result in the LUKS
1500 * header. This hash is used when opening the encrypted
1501 * device to verify that the user password unlocked a
1504 if (qcrypto_pbkdf2(luks_opts.hash_alg,
1505 masterkey, luks->header.master_key_len,
1506 luks->header.master_key_salt,
1507 QCRYPTO_BLOCK_LUKS_SALT_LEN,
1508 luks->header.master_key_iterations,
1509 luks->header.master_key_digest,
1510 QCRYPTO_BLOCK_LUKS_DIGEST_LEN,
1515 /* start with the sector that follows the header*/
1516 header_sectors = QCRYPTO_BLOCK_LUKS_KEY_SLOT_OFFSET /
1517 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
1520 qcrypto_block_luks_splitkeylen_sectors(luks,
1522 QCRYPTO_BLOCK_LUKS_STRIPES);
1524 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1525 QCryptoBlockLUKSKeySlot *slot = &luks->header.key_slots[i];
1526 slot->active = QCRYPTO_BLOCK_LUKS_KEY_SLOT_DISABLED;
1528 slot->key_offset_sector = header_sectors + i * split_key_sectors;
1529 slot->stripes = QCRYPTO_BLOCK_LUKS_STRIPES;
1532 /* The total size of the LUKS headers is the partition header + key
1533 * slot headers, rounded up to the nearest sector, combined with
1534 * the size of each master key material region, also rounded up
1535 * to the nearest sector */
1536 luks->header.payload_offset_sector = header_sectors +
1537 QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS * split_key_sectors;
1539 block->sector_size = QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
1540 block->payload_offset = luks->header.payload_offset_sector *
1543 /* Reserve header space to match payload offset */
1544 initfunc(block, block->payload_offset, opaque, &local_err);
1546 error_propagate(errp, local_err);
1551 /* populate the slot 0 with the password encrypted master key*/
1552 /* This will also store the header */
1553 if (qcrypto_block_luks_store_key(block,
1557 luks_opts.iter_time,
1564 memset(masterkey, 0, luks->header.master_key_len);
1570 memset(masterkey, 0, luks->header.master_key_len);
1573 qcrypto_block_free_cipher(block);
1574 qcrypto_ivgen_free(block->ivgen);
1576 g_free(luks->secret);
1582 qcrypto_block_luks_amend_add_keyslot(QCryptoBlock *block,
1583 QCryptoBlockReadFunc readfunc,
1584 QCryptoBlockWriteFunc writefunc,
1586 QCryptoBlockAmendOptionsLUKS *opts_luks,
1590 QCryptoBlockLUKS *luks = block->opaque;
1591 uint64_t iter_time = opts_luks->has_iter_time ?
1592 opts_luks->iter_time :
1593 QCRYPTO_BLOCK_LUKS_DEFAULT_ITER_TIME_MS;
1595 g_autofree char *old_password = NULL;
1596 g_autofree char *new_password = NULL;
1597 g_autofree uint8_t *master_key = NULL;
1599 char *secret = opts_luks->secret ?: luks->secret;
1601 if (!opts_luks->new_secret) {
1602 error_setg(errp, "'new-secret' is required to activate a keyslot");
1605 if (opts_luks->old_secret) {
1607 "'old-secret' must not be given when activating keyslots");
1611 if (opts_luks->has_keyslot) {
1612 keyslot = opts_luks->keyslot;
1613 if (keyslot < 0 || keyslot >= QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS) {
1615 "Invalid keyslot %u specified, must be between 0 and %u",
1616 keyslot, QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS - 1);
1620 keyslot = qcrypto_block_luks_find_free_keyslot(luks);
1621 if (keyslot == -1) {
1623 "Can't add a keyslot - all keyslots are in use");
1628 if (!force && qcrypto_block_luks_slot_active(luks, keyslot)) {
1630 "Refusing to overwrite active keyslot %i - "
1631 "please erase it first",
1636 /* Locate the password that will be used to retrieve the master key */
1637 old_password = qcrypto_secret_lookup_as_utf8(secret, errp);
1638 if (!old_password) {
1642 /* Retrieve the master key */
1643 master_key = g_new0(uint8_t, luks->header.master_key_len);
1645 if (qcrypto_block_luks_find_key(block, old_password, master_key,
1646 readfunc, opaque, errp) < 0) {
1647 error_append_hint(errp, "Failed to retrieve the master key");
1651 /* Locate the new password*/
1652 new_password = qcrypto_secret_lookup_as_utf8(opts_luks->new_secret, errp);
1653 if (!new_password) {
1657 /* Now set the new keyslots */
1658 if (qcrypto_block_luks_store_key(block, keyslot, new_password, master_key,
1659 iter_time, writefunc, opaque, errp)) {
1660 error_append_hint(errp, "Failed to write to keyslot %i", keyslot);
1667 qcrypto_block_luks_amend_erase_keyslots(QCryptoBlock *block,
1668 QCryptoBlockReadFunc readfunc,
1669 QCryptoBlockWriteFunc writefunc,
1671 QCryptoBlockAmendOptionsLUKS *opts_luks,
1675 QCryptoBlockLUKS *luks = block->opaque;
1676 g_autofree uint8_t *tmpkey = NULL;
1677 g_autofree char *old_password = NULL;
1679 if (opts_luks->new_secret) {
1681 "'new-secret' must not be given when erasing keyslots");
1684 if (opts_luks->has_iter_time) {
1686 "'iter-time' must not be given when erasing keyslots");
1689 if (opts_luks->secret) {
1691 "'secret' must not be given when erasing keyslots");
1695 /* Load the old password if given */
1696 if (opts_luks->old_secret) {
1697 old_password = qcrypto_secret_lookup_as_utf8(opts_luks->old_secret,
1699 if (!old_password) {
1704 * Allocate a temporary key buffer that we will need when
1705 * checking if slot matches the given old password
1707 tmpkey = g_new0(uint8_t, luks->header.master_key_len);
1710 /* Erase an explicitly given keyslot */
1711 if (opts_luks->has_keyslot) {
1712 int keyslot = opts_luks->keyslot;
1714 if (keyslot < 0 || keyslot >= QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS) {
1716 "Invalid keyslot %i specified, must be between 0 and %i",
1717 keyslot, QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS - 1);
1721 if (opts_luks->old_secret) {
1722 int rv = qcrypto_block_luks_load_key(block,
1731 } else if (rv == 0) {
1733 "Given keyslot %i doesn't contain the given "
1734 "old password for erase operation",
1740 if (!force && !qcrypto_block_luks_slot_active(luks, keyslot)) {
1742 "Given keyslot %i is already erased (inactive) ",
1747 if (!force && qcrypto_block_luks_count_active_slots(luks) == 1) {
1749 "Attempt to erase the only active keyslot %i "
1750 "which will erase all the data in the image "
1751 "irreversibly - refusing operation",
1756 if (qcrypto_block_luks_erase_key(block, keyslot,
1757 writefunc, opaque, errp)) {
1758 error_append_hint(errp, "Failed to erase keyslot %i", keyslot);
1762 /* Erase all keyslots that match the given old password */
1763 } else if (opts_luks->old_secret) {
1765 unsigned long slots_to_erase_bitmap = 0;
1769 assert(QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS <=
1770 sizeof(slots_to_erase_bitmap) * 8);
1772 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1773 int rv = qcrypto_block_luks_load_key(block,
1782 } else if (rv == 1) {
1783 bitmap_set(&slots_to_erase_bitmap, i, 1);
1787 slot_count = bitmap_count_one(&slots_to_erase_bitmap,
1788 QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS);
1789 if (slot_count == 0) {
1791 "No keyslots match given (old) password for erase operation");
1796 slot_count == qcrypto_block_luks_count_active_slots(luks)) {
1798 "All the active keyslots match the (old) password that "
1799 "was given and erasing them will erase all the data in "
1800 "the image irreversibly - refusing operation");
1804 /* Now apply the update */
1805 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1806 if (!test_bit(i, &slots_to_erase_bitmap)) {
1809 if (qcrypto_block_luks_erase_key(block, i, writefunc,
1811 error_append_hint(errp, "Failed to erase keyslot %zu", i);
1817 "To erase keyslot(s), either explicit keyslot index "
1818 "or the password currently contained in them must be given");
1825 qcrypto_block_luks_amend_options(QCryptoBlock *block,
1826 QCryptoBlockReadFunc readfunc,
1827 QCryptoBlockWriteFunc writefunc,
1829 QCryptoBlockAmendOptions *options,
1833 QCryptoBlockAmendOptionsLUKS *opts_luks = &options->u.luks;
1835 switch (opts_luks->state) {
1836 case Q_CRYPTO_BLOCKLUKS_KEYSLOT_STATE_ACTIVE:
1837 return qcrypto_block_luks_amend_add_keyslot(block, readfunc,
1839 opts_luks, force, errp);
1840 case Q_CRYPTO_BLOCKLUKS_KEYSLOT_STATE_INACTIVE:
1841 return qcrypto_block_luks_amend_erase_keyslots(block, readfunc,
1843 opts_luks, force, errp);
1845 g_assert_not_reached();
1849 static int qcrypto_block_luks_get_info(QCryptoBlock *block,
1850 QCryptoBlockInfo *info,
1853 QCryptoBlockLUKS *luks = block->opaque;
1854 QCryptoBlockInfoLUKSSlot *slot;
1855 QCryptoBlockInfoLUKSSlotList **tail = &info->u.luks.slots;
1858 info->u.luks.cipher_alg = luks->cipher_alg;
1859 info->u.luks.cipher_mode = luks->cipher_mode;
1860 info->u.luks.ivgen_alg = luks->ivgen_alg;
1861 if (info->u.luks.ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
1862 info->u.luks.has_ivgen_hash_alg = true;
1863 info->u.luks.ivgen_hash_alg = luks->ivgen_hash_alg;
1865 info->u.luks.hash_alg = luks->hash_alg;
1866 info->u.luks.payload_offset = block->payload_offset;
1867 info->u.luks.master_key_iters = luks->header.master_key_iterations;
1868 info->u.luks.uuid = g_strndup((const char *)luks->header.uuid,
1869 sizeof(luks->header.uuid));
1871 for (i = 0; i < QCRYPTO_BLOCK_LUKS_NUM_KEY_SLOTS; i++) {
1872 slot = g_new0(QCryptoBlockInfoLUKSSlot, 1);
1873 slot->active = luks->header.key_slots[i].active ==
1874 QCRYPTO_BLOCK_LUKS_KEY_SLOT_ENABLED;
1875 slot->key_offset = luks->header.key_slots[i].key_offset_sector
1876 * QCRYPTO_BLOCK_LUKS_SECTOR_SIZE;
1878 slot->has_iters = true;
1879 slot->iters = luks->header.key_slots[i].iterations;
1880 slot->has_stripes = true;
1881 slot->stripes = luks->header.key_slots[i].stripes;
1884 QAPI_LIST_APPEND(tail, slot);
1891 static void qcrypto_block_luks_cleanup(QCryptoBlock *block)
1893 QCryptoBlockLUKS *luks = block->opaque;
1895 g_free(luks->secret);
1902 qcrypto_block_luks_decrypt(QCryptoBlock *block,
1908 assert(QEMU_IS_ALIGNED(offset, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
1909 assert(QEMU_IS_ALIGNED(len, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
1910 return qcrypto_block_decrypt_helper(block,
1911 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
1912 offset, buf, len, errp);
1917 qcrypto_block_luks_encrypt(QCryptoBlock *block,
1923 assert(QEMU_IS_ALIGNED(offset, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
1924 assert(QEMU_IS_ALIGNED(len, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE));
1925 return qcrypto_block_encrypt_helper(block,
1926 QCRYPTO_BLOCK_LUKS_SECTOR_SIZE,
1927 offset, buf, len, errp);
1931 const QCryptoBlockDriver qcrypto_block_driver_luks = {
1932 .open = qcrypto_block_luks_open,
1933 .create = qcrypto_block_luks_create,
1934 .amend = qcrypto_block_luks_amend_options,
1935 .get_info = qcrypto_block_luks_get_info,
1936 .cleanup = qcrypto_block_luks_cleanup,
1937 .decrypt = qcrypto_block_luks_decrypt,
1938 .encrypt = qcrypto_block_luks_encrypt,
1939 .has_format = qcrypto_block_luks_has_format,