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1/*
2 * Copyright (C) 2003 Jana Saout <jana@saout.de>
3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
4 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com>
6 *
7 * This file is released under the GPL.
8 */
9
10#include <linux/completion.h>
11#include <linux/err.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/key.h>
16#include <linux/bio.h>
17#include <linux/blkdev.h>
18#include <linux/mempool.h>
19#include <linux/slab.h>
20#include <linux/crypto.h>
21#include <linux/workqueue.h>
22#include <linux/kthread.h>
23#include <linux/backing-dev.h>
24#include <linux/atomic.h>
25#include <linux/scatterlist.h>
26#include <linux/rbtree.h>
27#include <linux/ctype.h>
28#include <asm/page.h>
29#include <asm/unaligned.h>
30#include <crypto/hash.h>
31#include <crypto/md5.h>
32#include <crypto/algapi.h>
33#include <crypto/skcipher.h>
34#include <crypto/aead.h>
35#include <crypto/authenc.h>
36#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
37#include <linux/key-type.h>
38#include <keys/user-type.h>
39#include <keys/encrypted-type.h>
40
41#include <linux/device-mapper.h>
42
43#define DM_MSG_PREFIX "crypt"
44
45/*
46 * context holding the current state of a multi-part conversion
47 */
48struct convert_context {
49 struct completion restart;
50 struct bio *bio_in;
51 struct bio *bio_out;
52 struct bvec_iter iter_in;
53 struct bvec_iter iter_out;
54 u64 cc_sector;
55 atomic_t cc_pending;
56 union {
57 struct skcipher_request *req;
58 struct aead_request *req_aead;
59 } r;
60
61};
62
63/*
64 * per bio private data
65 */
66struct dm_crypt_io {
67 struct crypt_config *cc;
68 struct bio *base_bio;
69 u8 *integrity_metadata;
70 bool integrity_metadata_from_pool;
71 struct work_struct work;
72 struct tasklet_struct tasklet;
73
74 struct convert_context ctx;
75
76 atomic_t io_pending;
77 blk_status_t error;
78 sector_t sector;
79
80 struct rb_node rb_node;
81} CRYPTO_MINALIGN_ATTR;
82
83struct dm_crypt_request {
84 struct convert_context *ctx;
85 struct scatterlist sg_in[4];
86 struct scatterlist sg_out[4];
87 u64 iv_sector;
88};
89
90struct crypt_config;
91
92struct crypt_iv_operations {
93 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
94 const char *opts);
95 void (*dtr)(struct crypt_config *cc);
96 int (*init)(struct crypt_config *cc);
97 int (*wipe)(struct crypt_config *cc);
98 int (*generator)(struct crypt_config *cc, u8 *iv,
99 struct dm_crypt_request *dmreq);
100 int (*post)(struct crypt_config *cc, u8 *iv,
101 struct dm_crypt_request *dmreq);
102};
103
104struct iv_benbi_private {
105 int shift;
106};
107
108#define LMK_SEED_SIZE 64 /* hash + 0 */
109struct iv_lmk_private {
110 struct crypto_shash *hash_tfm;
111 u8 *seed;
112};
113
114#define TCW_WHITENING_SIZE 16
115struct iv_tcw_private {
116 struct crypto_shash *crc32_tfm;
117 u8 *iv_seed;
118 u8 *whitening;
119};
120
121#define ELEPHANT_MAX_KEY_SIZE 32
122struct iv_elephant_private {
123 struct crypto_skcipher *tfm;
124};
125
126/*
127 * Crypt: maps a linear range of a block device
128 * and encrypts / decrypts at the same time.
129 */
130enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
131 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD,
132 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE,
133 DM_CRYPT_WRITE_INLINE };
134
135enum cipher_flags {
136 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cihper */
137 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */
138 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */
139};
140
141/*
142 * The fields in here must be read only after initialization.
143 */
144struct crypt_config {
145 struct dm_dev *dev;
146 sector_t start;
147
148 struct percpu_counter n_allocated_pages;
149
150 struct workqueue_struct *io_queue;
151 struct workqueue_struct *crypt_queue;
152
153 spinlock_t write_thread_lock;
154 struct task_struct *write_thread;
155 struct rb_root write_tree;
156
157 char *cipher_string;
158 char *cipher_auth;
159 char *key_string;
160
161 const struct crypt_iv_operations *iv_gen_ops;
162 union {
163 struct iv_benbi_private benbi;
164 struct iv_lmk_private lmk;
165 struct iv_tcw_private tcw;
166 struct iv_elephant_private elephant;
167 } iv_gen_private;
168 u64 iv_offset;
169 unsigned int iv_size;
170 unsigned short int sector_size;
171 unsigned char sector_shift;
172
173 union {
174 struct crypto_skcipher **tfms;
175 struct crypto_aead **tfms_aead;
176 } cipher_tfm;
177 unsigned tfms_count;
178 unsigned long cipher_flags;
179
180 /*
181 * Layout of each crypto request:
182 *
183 * struct skcipher_request
184 * context
185 * padding
186 * struct dm_crypt_request
187 * padding
188 * IV
189 *
190 * The padding is added so that dm_crypt_request and the IV are
191 * correctly aligned.
192 */
193 unsigned int dmreq_start;
194
195 unsigned int per_bio_data_size;
196
197 unsigned long flags;
198 unsigned int key_size;
199 unsigned int key_parts; /* independent parts in key buffer */
200 unsigned int key_extra_size; /* additional keys length */
201 unsigned int key_mac_size; /* MAC key size for authenc(...) */
202
203 unsigned int integrity_tag_size;
204 unsigned int integrity_iv_size;
205 unsigned int on_disk_tag_size;
206
207 /*
208 * pool for per bio private data, crypto requests,
209 * encryption requeusts/buffer pages and integrity tags
210 */
211 unsigned tag_pool_max_sectors;
212 mempool_t tag_pool;
213 mempool_t req_pool;
214 mempool_t page_pool;
215
216 struct bio_set bs;
217 struct mutex bio_alloc_lock;
218
219 u8 *authenc_key; /* space for keys in authenc() format (if used) */
220 u8 key[];
221};
222
223#define MIN_IOS 64
224#define MAX_TAG_SIZE 480
225#define POOL_ENTRY_SIZE 512
226
227static DEFINE_SPINLOCK(dm_crypt_clients_lock);
228static unsigned dm_crypt_clients_n = 0;
229static volatile unsigned long dm_crypt_pages_per_client;
230#define DM_CRYPT_MEMORY_PERCENT 2
231#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_PAGES * 16)
232
233static void clone_init(struct dm_crypt_io *, struct bio *);
234static void kcryptd_queue_crypt(struct dm_crypt_io *io);
235static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
236 struct scatterlist *sg);
237
238static bool crypt_integrity_aead(struct crypt_config *cc);
239
240/*
241 * Use this to access cipher attributes that are independent of the key.
242 */
243static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
244{
245 return cc->cipher_tfm.tfms[0];
246}
247
248static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
249{
250 return cc->cipher_tfm.tfms_aead[0];
251}
252
253/*
254 * Different IV generation algorithms:
255 *
256 * plain: the initial vector is the 32-bit little-endian version of the sector
257 * number, padded with zeros if necessary.
258 *
259 * plain64: the initial vector is the 64-bit little-endian version of the sector
260 * number, padded with zeros if necessary.
261 *
262 * plain64be: the initial vector is the 64-bit big-endian version of the sector
263 * number, padded with zeros if necessary.
264 *
265 * essiv: "encrypted sector|salt initial vector", the sector number is
266 * encrypted with the bulk cipher using a salt as key. The salt
267 * should be derived from the bulk cipher's key via hashing.
268 *
269 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
270 * (needed for LRW-32-AES and possible other narrow block modes)
271 *
272 * null: the initial vector is always zero. Provides compatibility with
273 * obsolete loop_fish2 devices. Do not use for new devices.
274 *
275 * lmk: Compatible implementation of the block chaining mode used
276 * by the Loop-AES block device encryption system
277 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
278 * It operates on full 512 byte sectors and uses CBC
279 * with an IV derived from the sector number, the data and
280 * optionally extra IV seed.
281 * This means that after decryption the first block
282 * of sector must be tweaked according to decrypted data.
283 * Loop-AES can use three encryption schemes:
284 * version 1: is plain aes-cbc mode
285 * version 2: uses 64 multikey scheme with lmk IV generator
286 * version 3: the same as version 2 with additional IV seed
287 * (it uses 65 keys, last key is used as IV seed)
288 *
289 * tcw: Compatible implementation of the block chaining mode used
290 * by the TrueCrypt device encryption system (prior to version 4.1).
291 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
292 * It operates on full 512 byte sectors and uses CBC
293 * with an IV derived from initial key and the sector number.
294 * In addition, whitening value is applied on every sector, whitening
295 * is calculated from initial key, sector number and mixed using CRC32.
296 * Note that this encryption scheme is vulnerable to watermarking attacks
297 * and should be used for old compatible containers access only.
298 *
299 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
300 * The IV is encrypted little-endian byte-offset (with the same key
301 * and cipher as the volume).
302 *
303 * elephant: The extended version of eboiv with additional Elephant diffuser
304 * used with Bitlocker CBC mode.
305 * This mode was used in older Windows systems
306 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
307 */
308
309static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
310 struct dm_crypt_request *dmreq)
311{
312 memset(iv, 0, cc->iv_size);
313 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
314
315 return 0;
316}
317
318static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
319 struct dm_crypt_request *dmreq)
320{
321 memset(iv, 0, cc->iv_size);
322 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
323
324 return 0;
325}
326
327static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
328 struct dm_crypt_request *dmreq)
329{
330 memset(iv, 0, cc->iv_size);
331 /* iv_size is at least of size u64; usually it is 16 bytes */
332 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
333
334 return 0;
335}
336
337static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
338 struct dm_crypt_request *dmreq)
339{
340 /*
341 * ESSIV encryption of the IV is now handled by the crypto API,
342 * so just pass the plain sector number here.
343 */
344 memset(iv, 0, cc->iv_size);
345 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
346
347 return 0;
348}
349
350static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
351 const char *opts)
352{
353 unsigned bs;
354 int log;
355
356 if (crypt_integrity_aead(cc))
357 bs = crypto_aead_blocksize(any_tfm_aead(cc));
358 else
359 bs = crypto_skcipher_blocksize(any_tfm(cc));
360 log = ilog2(bs);
361
362 /* we need to calculate how far we must shift the sector count
363 * to get the cipher block count, we use this shift in _gen */
364
365 if (1 << log != bs) {
366 ti->error = "cypher blocksize is not a power of 2";
367 return -EINVAL;
368 }
369
370 if (log > 9) {
371 ti->error = "cypher blocksize is > 512";
372 return -EINVAL;
373 }
374
375 cc->iv_gen_private.benbi.shift = 9 - log;
376
377 return 0;
378}
379
380static void crypt_iv_benbi_dtr(struct crypt_config *cc)
381{
382}
383
384static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
385 struct dm_crypt_request *dmreq)
386{
387 __be64 val;
388
389 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
390
391 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
392 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
393
394 return 0;
395}
396
397static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
398 struct dm_crypt_request *dmreq)
399{
400 memset(iv, 0, cc->iv_size);
401
402 return 0;
403}
404
405static void crypt_iv_lmk_dtr(struct crypt_config *cc)
406{
407 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
408
409 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
410 crypto_free_shash(lmk->hash_tfm);
411 lmk->hash_tfm = NULL;
412
413 kfree_sensitive(lmk->seed);
414 lmk->seed = NULL;
415}
416
417static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
418 const char *opts)
419{
420 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
421
422 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
423 ti->error = "Unsupported sector size for LMK";
424 return -EINVAL;
425 }
426
427 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
428 if (IS_ERR(lmk->hash_tfm)) {
429 ti->error = "Error initializing LMK hash";
430 return PTR_ERR(lmk->hash_tfm);
431 }
432
433 /* No seed in LMK version 2 */
434 if (cc->key_parts == cc->tfms_count) {
435 lmk->seed = NULL;
436 return 0;
437 }
438
439 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
440 if (!lmk->seed) {
441 crypt_iv_lmk_dtr(cc);
442 ti->error = "Error kmallocing seed storage in LMK";
443 return -ENOMEM;
444 }
445
446 return 0;
447}
448
449static int crypt_iv_lmk_init(struct crypt_config *cc)
450{
451 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
452 int subkey_size = cc->key_size / cc->key_parts;
453
454 /* LMK seed is on the position of LMK_KEYS + 1 key */
455 if (lmk->seed)
456 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
457 crypto_shash_digestsize(lmk->hash_tfm));
458
459 return 0;
460}
461
462static int crypt_iv_lmk_wipe(struct crypt_config *cc)
463{
464 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
465
466 if (lmk->seed)
467 memset(lmk->seed, 0, LMK_SEED_SIZE);
468
469 return 0;
470}
471
472static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
473 struct dm_crypt_request *dmreq,
474 u8 *data)
475{
476 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
477 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
478 struct md5_state md5state;
479 __le32 buf[4];
480 int i, r;
481
482 desc->tfm = lmk->hash_tfm;
483
484 r = crypto_shash_init(desc);
485 if (r)
486 return r;
487
488 if (lmk->seed) {
489 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
490 if (r)
491 return r;
492 }
493
494 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
495 r = crypto_shash_update(desc, data + 16, 16 * 31);
496 if (r)
497 return r;
498
499 /* Sector is cropped to 56 bits here */
500 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
501 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
502 buf[2] = cpu_to_le32(4024);
503 buf[3] = 0;
504 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
505 if (r)
506 return r;
507
508 /* No MD5 padding here */
509 r = crypto_shash_export(desc, &md5state);
510 if (r)
511 return r;
512
513 for (i = 0; i < MD5_HASH_WORDS; i++)
514 __cpu_to_le32s(&md5state.hash[i]);
515 memcpy(iv, &md5state.hash, cc->iv_size);
516
517 return 0;
518}
519
520static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
521 struct dm_crypt_request *dmreq)
522{
523 struct scatterlist *sg;
524 u8 *src;
525 int r = 0;
526
527 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
528 sg = crypt_get_sg_data(cc, dmreq->sg_in);
529 src = kmap_atomic(sg_page(sg));
530 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
531 kunmap_atomic(src);
532 } else
533 memset(iv, 0, cc->iv_size);
534
535 return r;
536}
537
538static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
539 struct dm_crypt_request *dmreq)
540{
541 struct scatterlist *sg;
542 u8 *dst;
543 int r;
544
545 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
546 return 0;
547
548 sg = crypt_get_sg_data(cc, dmreq->sg_out);
549 dst = kmap_atomic(sg_page(sg));
550 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
551
552 /* Tweak the first block of plaintext sector */
553 if (!r)
554 crypto_xor(dst + sg->offset, iv, cc->iv_size);
555
556 kunmap_atomic(dst);
557 return r;
558}
559
560static void crypt_iv_tcw_dtr(struct crypt_config *cc)
561{
562 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
563
564 kfree_sensitive(tcw->iv_seed);
565 tcw->iv_seed = NULL;
566 kfree_sensitive(tcw->whitening);
567 tcw->whitening = NULL;
568
569 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
570 crypto_free_shash(tcw->crc32_tfm);
571 tcw->crc32_tfm = NULL;
572}
573
574static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
575 const char *opts)
576{
577 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
578
579 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
580 ti->error = "Unsupported sector size for TCW";
581 return -EINVAL;
582 }
583
584 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
585 ti->error = "Wrong key size for TCW";
586 return -EINVAL;
587 }
588
589 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0);
590 if (IS_ERR(tcw->crc32_tfm)) {
591 ti->error = "Error initializing CRC32 in TCW";
592 return PTR_ERR(tcw->crc32_tfm);
593 }
594
595 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
596 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
597 if (!tcw->iv_seed || !tcw->whitening) {
598 crypt_iv_tcw_dtr(cc);
599 ti->error = "Error allocating seed storage in TCW";
600 return -ENOMEM;
601 }
602
603 return 0;
604}
605
606static int crypt_iv_tcw_init(struct crypt_config *cc)
607{
608 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
609 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
610
611 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
612 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
613 TCW_WHITENING_SIZE);
614
615 return 0;
616}
617
618static int crypt_iv_tcw_wipe(struct crypt_config *cc)
619{
620 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
621
622 memset(tcw->iv_seed, 0, cc->iv_size);
623 memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
624
625 return 0;
626}
627
628static int crypt_iv_tcw_whitening(struct crypt_config *cc,
629 struct dm_crypt_request *dmreq,
630 u8 *data)
631{
632 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
633 __le64 sector = cpu_to_le64(dmreq->iv_sector);
634 u8 buf[TCW_WHITENING_SIZE];
635 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
636 int i, r;
637
638 /* xor whitening with sector number */
639 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8);
640 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8);
641
642 /* calculate crc32 for every 32bit part and xor it */
643 desc->tfm = tcw->crc32_tfm;
644 for (i = 0; i < 4; i++) {
645 r = crypto_shash_init(desc);
646 if (r)
647 goto out;
648 r = crypto_shash_update(desc, &buf[i * 4], 4);
649 if (r)
650 goto out;
651 r = crypto_shash_final(desc, &buf[i * 4]);
652 if (r)
653 goto out;
654 }
655 crypto_xor(&buf[0], &buf[12], 4);
656 crypto_xor(&buf[4], &buf[8], 4);
657
658 /* apply whitening (8 bytes) to whole sector */
659 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
660 crypto_xor(data + i * 8, buf, 8);
661out:
662 memzero_explicit(buf, sizeof(buf));
663 return r;
664}
665
666static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
667 struct dm_crypt_request *dmreq)
668{
669 struct scatterlist *sg;
670 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
671 __le64 sector = cpu_to_le64(dmreq->iv_sector);
672 u8 *src;
673 int r = 0;
674
675 /* Remove whitening from ciphertext */
676 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
677 sg = crypt_get_sg_data(cc, dmreq->sg_in);
678 src = kmap_atomic(sg_page(sg));
679 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
680 kunmap_atomic(src);
681 }
682
683 /* Calculate IV */
684 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8);
685 if (cc->iv_size > 8)
686 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or,
687 cc->iv_size - 8);
688
689 return r;
690}
691
692static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
693 struct dm_crypt_request *dmreq)
694{
695 struct scatterlist *sg;
696 u8 *dst;
697 int r;
698
699 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
700 return 0;
701
702 /* Apply whitening on ciphertext */
703 sg = crypt_get_sg_data(cc, dmreq->sg_out);
704 dst = kmap_atomic(sg_page(sg));
705 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
706 kunmap_atomic(dst);
707
708 return r;
709}
710
711static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
712 struct dm_crypt_request *dmreq)
713{
714 /* Used only for writes, there must be an additional space to store IV */
715 get_random_bytes(iv, cc->iv_size);
716 return 0;
717}
718
719static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
720 const char *opts)
721{
722 if (crypt_integrity_aead(cc)) {
723 ti->error = "AEAD transforms not supported for EBOIV";
724 return -EINVAL;
725 }
726
727 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
728 ti->error = "Block size of EBOIV cipher does "
729 "not match IV size of block cipher";
730 return -EINVAL;
731 }
732
733 return 0;
734}
735
736static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
737 struct dm_crypt_request *dmreq)
738{
739 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64));
740 struct skcipher_request *req;
741 struct scatterlist src, dst;
742 DECLARE_CRYPTO_WAIT(wait);
743 int err;
744
745 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO);
746 if (!req)
747 return -ENOMEM;
748
749 memset(buf, 0, cc->iv_size);
750 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
751
752 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
753 sg_init_one(&dst, iv, cc->iv_size);
754 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
755 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
756 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
757 skcipher_request_free(req);
758
759 return err;
760}
761
762static void crypt_iv_elephant_dtr(struct crypt_config *cc)
763{
764 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
765
766 crypto_free_skcipher(elephant->tfm);
767 elephant->tfm = NULL;
768}
769
770static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
771 const char *opts)
772{
773 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
774 int r;
775
776 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
777 if (IS_ERR(elephant->tfm)) {
778 r = PTR_ERR(elephant->tfm);
779 elephant->tfm = NULL;
780 return r;
781 }
782
783 r = crypt_iv_eboiv_ctr(cc, ti, NULL);
784 if (r)
785 crypt_iv_elephant_dtr(cc);
786 return r;
787}
788
789static void diffuser_disk_to_cpu(u32 *d, size_t n)
790{
791#ifndef __LITTLE_ENDIAN
792 int i;
793
794 for (i = 0; i < n; i++)
795 d[i] = le32_to_cpu((__le32)d[i]);
796#endif
797}
798
799static void diffuser_cpu_to_disk(__le32 *d, size_t n)
800{
801#ifndef __LITTLE_ENDIAN
802 int i;
803
804 for (i = 0; i < n; i++)
805 d[i] = cpu_to_le32((u32)d[i]);
806#endif
807}
808
809static void diffuser_a_decrypt(u32 *d, size_t n)
810{
811 int i, i1, i2, i3;
812
813 for (i = 0; i < 5; i++) {
814 i1 = 0;
815 i2 = n - 2;
816 i3 = n - 5;
817
818 while (i1 < (n - 1)) {
819 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
820 i1++; i2++; i3++;
821
822 if (i3 >= n)
823 i3 -= n;
824
825 d[i1] += d[i2] ^ d[i3];
826 i1++; i2++; i3++;
827
828 if (i2 >= n)
829 i2 -= n;
830
831 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
832 i1++; i2++; i3++;
833
834 d[i1] += d[i2] ^ d[i3];
835 i1++; i2++; i3++;
836 }
837 }
838}
839
840static void diffuser_a_encrypt(u32 *d, size_t n)
841{
842 int i, i1, i2, i3;
843
844 for (i = 0; i < 5; i++) {
845 i1 = n - 1;
846 i2 = n - 2 - 1;
847 i3 = n - 5 - 1;
848
849 while (i1 > 0) {
850 d[i1] -= d[i2] ^ d[i3];
851 i1--; i2--; i3--;
852
853 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
854 i1--; i2--; i3--;
855
856 if (i2 < 0)
857 i2 += n;
858
859 d[i1] -= d[i2] ^ d[i3];
860 i1--; i2--; i3--;
861
862 if (i3 < 0)
863 i3 += n;
864
865 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
866 i1--; i2--; i3--;
867 }
868 }
869}
870
871static void diffuser_b_decrypt(u32 *d, size_t n)
872{
873 int i, i1, i2, i3;
874
875 for (i = 0; i < 3; i++) {
876 i1 = 0;
877 i2 = 2;
878 i3 = 5;
879
880 while (i1 < (n - 1)) {
881 d[i1] += d[i2] ^ d[i3];
882 i1++; i2++; i3++;
883
884 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
885 i1++; i2++; i3++;
886
887 if (i2 >= n)
888 i2 -= n;
889
890 d[i1] += d[i2] ^ d[i3];
891 i1++; i2++; i3++;
892
893 if (i3 >= n)
894 i3 -= n;
895
896 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
897 i1++; i2++; i3++;
898 }
899 }
900}
901
902static void diffuser_b_encrypt(u32 *d, size_t n)
903{
904 int i, i1, i2, i3;
905
906 for (i = 0; i < 3; i++) {
907 i1 = n - 1;
908 i2 = 2 - 1;
909 i3 = 5 - 1;
910
911 while (i1 > 0) {
912 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
913 i1--; i2--; i3--;
914
915 if (i3 < 0)
916 i3 += n;
917
918 d[i1] -= d[i2] ^ d[i3];
919 i1--; i2--; i3--;
920
921 if (i2 < 0)
922 i2 += n;
923
924 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
925 i1--; i2--; i3--;
926
927 d[i1] -= d[i2] ^ d[i3];
928 i1--; i2--; i3--;
929 }
930 }
931}
932
933static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq)
934{
935 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
936 u8 *es, *ks, *data, *data2, *data_offset;
937 struct skcipher_request *req;
938 struct scatterlist *sg, *sg2, src, dst;
939 DECLARE_CRYPTO_WAIT(wait);
940 int i, r;
941
942 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO);
943 es = kzalloc(16, GFP_NOIO); /* Key for AES */
944 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */
945
946 if (!req || !es || !ks) {
947 r = -ENOMEM;
948 goto out;
949 }
950
951 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
952
953 /* E(Ks, e(s)) */
954 sg_init_one(&src, es, 16);
955 sg_init_one(&dst, ks, 16);
956 skcipher_request_set_crypt(req, &src, &dst, 16, NULL);
957 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
958 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
959 if (r)
960 goto out;
961
962 /* E(Ks, e'(s)) */
963 es[15] = 0x80;
964 sg_init_one(&dst, &ks[16], 16);
965 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
966 if (r)
967 goto out;
968
969 sg = crypt_get_sg_data(cc, dmreq->sg_out);
970 data = kmap_atomic(sg_page(sg));
971 data_offset = data + sg->offset;
972
973 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */
974 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
975 sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
976 data2 = kmap_atomic(sg_page(sg2));
977 memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
978 kunmap_atomic(data2);
979 }
980
981 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
982 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
983 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
984 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
985 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
986 }
987
988 for (i = 0; i < (cc->sector_size / 32); i++)
989 crypto_xor(data_offset + i * 32, ks, 32);
990
991 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
992 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
993 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
994 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
995 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
996 }
997
998 kunmap_atomic(data);
999out:
1000 kfree_sensitive(ks);
1001 kfree_sensitive(es);
1002 skcipher_request_free(req);
1003 return r;
1004}
1005
1006static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
1007 struct dm_crypt_request *dmreq)
1008{
1009 int r;
1010
1011 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1012 r = crypt_iv_elephant(cc, dmreq);
1013 if (r)
1014 return r;
1015 }
1016
1017 return crypt_iv_eboiv_gen(cc, iv, dmreq);
1018}
1019
1020static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
1021 struct dm_crypt_request *dmreq)
1022{
1023 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
1024 return crypt_iv_elephant(cc, dmreq);
1025
1026 return 0;
1027}
1028
1029static int crypt_iv_elephant_init(struct crypt_config *cc)
1030{
1031 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1032 int key_offset = cc->key_size - cc->key_extra_size;
1033
1034 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size);
1035}
1036
1037static int crypt_iv_elephant_wipe(struct crypt_config *cc)
1038{
1039 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1040 u8 key[ELEPHANT_MAX_KEY_SIZE];
1041
1042 memset(key, 0, cc->key_extra_size);
1043 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size);
1044}
1045
1046static const struct crypt_iv_operations crypt_iv_plain_ops = {
1047 .generator = crypt_iv_plain_gen
1048};
1049
1050static const struct crypt_iv_operations crypt_iv_plain64_ops = {
1051 .generator = crypt_iv_plain64_gen
1052};
1053
1054static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
1055 .generator = crypt_iv_plain64be_gen
1056};
1057
1058static const struct crypt_iv_operations crypt_iv_essiv_ops = {
1059 .generator = crypt_iv_essiv_gen
1060};
1061
1062static const struct crypt_iv_operations crypt_iv_benbi_ops = {
1063 .ctr = crypt_iv_benbi_ctr,
1064 .dtr = crypt_iv_benbi_dtr,
1065 .generator = crypt_iv_benbi_gen
1066};
1067
1068static const struct crypt_iv_operations crypt_iv_null_ops = {
1069 .generator = crypt_iv_null_gen
1070};
1071
1072static const struct crypt_iv_operations crypt_iv_lmk_ops = {
1073 .ctr = crypt_iv_lmk_ctr,
1074 .dtr = crypt_iv_lmk_dtr,
1075 .init = crypt_iv_lmk_init,
1076 .wipe = crypt_iv_lmk_wipe,
1077 .generator = crypt_iv_lmk_gen,
1078 .post = crypt_iv_lmk_post
1079};
1080
1081static const struct crypt_iv_operations crypt_iv_tcw_ops = {
1082 .ctr = crypt_iv_tcw_ctr,
1083 .dtr = crypt_iv_tcw_dtr,
1084 .init = crypt_iv_tcw_init,
1085 .wipe = crypt_iv_tcw_wipe,
1086 .generator = crypt_iv_tcw_gen,
1087 .post = crypt_iv_tcw_post
1088};
1089
1090static struct crypt_iv_operations crypt_iv_random_ops = {
1091 .generator = crypt_iv_random_gen
1092};
1093
1094static struct crypt_iv_operations crypt_iv_eboiv_ops = {
1095 .ctr = crypt_iv_eboiv_ctr,
1096 .generator = crypt_iv_eboiv_gen
1097};
1098
1099static struct crypt_iv_operations crypt_iv_elephant_ops = {
1100 .ctr = crypt_iv_elephant_ctr,
1101 .dtr = crypt_iv_elephant_dtr,
1102 .init = crypt_iv_elephant_init,
1103 .wipe = crypt_iv_elephant_wipe,
1104 .generator = crypt_iv_elephant_gen,
1105 .post = crypt_iv_elephant_post
1106};
1107
1108/*
1109 * Integrity extensions
1110 */
1111static bool crypt_integrity_aead(struct crypt_config *cc)
1112{
1113 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
1114}
1115
1116static bool crypt_integrity_hmac(struct crypt_config *cc)
1117{
1118 return crypt_integrity_aead(cc) && cc->key_mac_size;
1119}
1120
1121/* Get sg containing data */
1122static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
1123 struct scatterlist *sg)
1124{
1125 if (unlikely(crypt_integrity_aead(cc)))
1126 return &sg[2];
1127
1128 return sg;
1129}
1130
1131static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
1132{
1133 struct bio_integrity_payload *bip;
1134 unsigned int tag_len;
1135 int ret;
1136
1137 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
1138 return 0;
1139
1140 bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
1141 if (IS_ERR(bip))
1142 return PTR_ERR(bip);
1143
1144 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift);
1145
1146 bip->bip_iter.bi_size = tag_len;
1147 bip->bip_iter.bi_sector = io->cc->start + io->sector;
1148
1149 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
1150 tag_len, offset_in_page(io->integrity_metadata));
1151 if (unlikely(ret != tag_len))
1152 return -ENOMEM;
1153
1154 return 0;
1155}
1156
1157static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
1158{
1159#ifdef CONFIG_BLK_DEV_INTEGRITY
1160 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
1161 struct mapped_device *md = dm_table_get_md(ti->table);
1162
1163 /* From now we require underlying device with our integrity profile */
1164 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
1165 ti->error = "Integrity profile not supported.";
1166 return -EINVAL;
1167 }
1168
1169 if (bi->tag_size != cc->on_disk_tag_size ||
1170 bi->tuple_size != cc->on_disk_tag_size) {
1171 ti->error = "Integrity profile tag size mismatch.";
1172 return -EINVAL;
1173 }
1174 if (1 << bi->interval_exp != cc->sector_size) {
1175 ti->error = "Integrity profile sector size mismatch.";
1176 return -EINVAL;
1177 }
1178
1179 if (crypt_integrity_aead(cc)) {
1180 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
1181 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
1182 cc->integrity_tag_size, cc->integrity_iv_size);
1183
1184 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
1185 ti->error = "Integrity AEAD auth tag size is not supported.";
1186 return -EINVAL;
1187 }
1188 } else if (cc->integrity_iv_size)
1189 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
1190 cc->integrity_iv_size);
1191
1192 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
1193 ti->error = "Not enough space for integrity tag in the profile.";
1194 return -EINVAL;
1195 }
1196
1197 return 0;
1198#else
1199 ti->error = "Integrity profile not supported.";
1200 return -EINVAL;
1201#endif
1202}
1203
1204static void crypt_convert_init(struct crypt_config *cc,
1205 struct convert_context *ctx,
1206 struct bio *bio_out, struct bio *bio_in,
1207 sector_t sector)
1208{
1209 ctx->bio_in = bio_in;
1210 ctx->bio_out = bio_out;
1211 if (bio_in)
1212 ctx->iter_in = bio_in->bi_iter;
1213 if (bio_out)
1214 ctx->iter_out = bio_out->bi_iter;
1215 ctx->cc_sector = sector + cc->iv_offset;
1216 init_completion(&ctx->restart);
1217}
1218
1219static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1220 void *req)
1221{
1222 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1223}
1224
1225static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1226{
1227 return (void *)((char *)dmreq - cc->dmreq_start);
1228}
1229
1230static u8 *iv_of_dmreq(struct crypt_config *cc,
1231 struct dm_crypt_request *dmreq)
1232{
1233 if (crypt_integrity_aead(cc))
1234 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1235 crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1236 else
1237 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1238 crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1239}
1240
1241static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1242 struct dm_crypt_request *dmreq)
1243{
1244 return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1245}
1246
1247static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
1248 struct dm_crypt_request *dmreq)
1249{
1250 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
1251 return (__le64 *) ptr;
1252}
1253
1254static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1255 struct dm_crypt_request *dmreq)
1256{
1257 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1258 cc->iv_size + sizeof(uint64_t);
1259 return (unsigned int*)ptr;
1260}
1261
1262static void *tag_from_dmreq(struct crypt_config *cc,
1263 struct dm_crypt_request *dmreq)
1264{
1265 struct convert_context *ctx = dmreq->ctx;
1266 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1267
1268 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1269 cc->on_disk_tag_size];
1270}
1271
1272static void *iv_tag_from_dmreq(struct crypt_config *cc,
1273 struct dm_crypt_request *dmreq)
1274{
1275 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1276}
1277
1278static int crypt_convert_block_aead(struct crypt_config *cc,
1279 struct convert_context *ctx,
1280 struct aead_request *req,
1281 unsigned int tag_offset)
1282{
1283 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1284 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1285 struct dm_crypt_request *dmreq;
1286 u8 *iv, *org_iv, *tag_iv, *tag;
1287 __le64 *sector;
1288 int r = 0;
1289
1290 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1291
1292 /* Reject unexpected unaligned bio. */
1293 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1294 return -EIO;
1295
1296 dmreq = dmreq_of_req(cc, req);
1297 dmreq->iv_sector = ctx->cc_sector;
1298 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1299 dmreq->iv_sector >>= cc->sector_shift;
1300 dmreq->ctx = ctx;
1301
1302 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1303
1304 sector = org_sector_of_dmreq(cc, dmreq);
1305 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1306
1307 iv = iv_of_dmreq(cc, dmreq);
1308 org_iv = org_iv_of_dmreq(cc, dmreq);
1309 tag = tag_from_dmreq(cc, dmreq);
1310 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1311
1312 /* AEAD request:
1313 * |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1314 * | (authenticated) | (auth+encryption) | |
1315 * | sector_LE | IV | sector in/out | tag in/out |
1316 */
1317 sg_init_table(dmreq->sg_in, 4);
1318 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1319 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1320 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1321 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1322
1323 sg_init_table(dmreq->sg_out, 4);
1324 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1325 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1326 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1327 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1328
1329 if (cc->iv_gen_ops) {
1330 /* For READs use IV stored in integrity metadata */
1331 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1332 memcpy(org_iv, tag_iv, cc->iv_size);
1333 } else {
1334 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1335 if (r < 0)
1336 return r;
1337 /* Store generated IV in integrity metadata */
1338 if (cc->integrity_iv_size)
1339 memcpy(tag_iv, org_iv, cc->iv_size);
1340 }
1341 /* Working copy of IV, to be modified in crypto API */
1342 memcpy(iv, org_iv, cc->iv_size);
1343 }
1344
1345 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1346 if (bio_data_dir(ctx->bio_in) == WRITE) {
1347 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1348 cc->sector_size, iv);
1349 r = crypto_aead_encrypt(req);
1350 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
1351 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1352 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1353 } else {
1354 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1355 cc->sector_size + cc->integrity_tag_size, iv);
1356 r = crypto_aead_decrypt(req);
1357 }
1358
1359 if (r == -EBADMSG) {
1360 char b[BDEVNAME_SIZE];
1361 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b),
1362 (unsigned long long)le64_to_cpu(*sector));
1363 }
1364
1365 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1366 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1367
1368 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1369 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1370
1371 return r;
1372}
1373
1374static int crypt_convert_block_skcipher(struct crypt_config *cc,
1375 struct convert_context *ctx,
1376 struct skcipher_request *req,
1377 unsigned int tag_offset)
1378{
1379 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1380 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1381 struct scatterlist *sg_in, *sg_out;
1382 struct dm_crypt_request *dmreq;
1383 u8 *iv, *org_iv, *tag_iv;
1384 __le64 *sector;
1385 int r = 0;
1386
1387 /* Reject unexpected unaligned bio. */
1388 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1389 return -EIO;
1390
1391 dmreq = dmreq_of_req(cc, req);
1392 dmreq->iv_sector = ctx->cc_sector;
1393 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1394 dmreq->iv_sector >>= cc->sector_shift;
1395 dmreq->ctx = ctx;
1396
1397 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1398
1399 iv = iv_of_dmreq(cc, dmreq);
1400 org_iv = org_iv_of_dmreq(cc, dmreq);
1401 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1402
1403 sector = org_sector_of_dmreq(cc, dmreq);
1404 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1405
1406 /* For skcipher we use only the first sg item */
1407 sg_in = &dmreq->sg_in[0];
1408 sg_out = &dmreq->sg_out[0];
1409
1410 sg_init_table(sg_in, 1);
1411 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1412
1413 sg_init_table(sg_out, 1);
1414 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1415
1416 if (cc->iv_gen_ops) {
1417 /* For READs use IV stored in integrity metadata */
1418 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1419 memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1420 } else {
1421 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1422 if (r < 0)
1423 return r;
1424 /* Data can be already preprocessed in generator */
1425 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
1426 sg_in = sg_out;
1427 /* Store generated IV in integrity metadata */
1428 if (cc->integrity_iv_size)
1429 memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1430 }
1431 /* Working copy of IV, to be modified in crypto API */
1432 memcpy(iv, org_iv, cc->iv_size);
1433 }
1434
1435 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1436
1437 if (bio_data_dir(ctx->bio_in) == WRITE)
1438 r = crypto_skcipher_encrypt(req);
1439 else
1440 r = crypto_skcipher_decrypt(req);
1441
1442 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1443 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1444
1445 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1446 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1447
1448 return r;
1449}
1450
1451static void kcryptd_async_done(struct crypto_async_request *async_req,
1452 int error);
1453
1454static void crypt_alloc_req_skcipher(struct crypt_config *cc,
1455 struct convert_context *ctx)
1456{
1457 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
1458
1459 if (!ctx->r.req)
1460 ctx->r.req = mempool_alloc(&cc->req_pool, GFP_NOIO);
1461
1462 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1463
1464 /*
1465 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1466 * requests if driver request queue is full.
1467 */
1468 skcipher_request_set_callback(ctx->r.req,
1469 CRYPTO_TFM_REQ_MAY_BACKLOG,
1470 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
1471}
1472
1473static void crypt_alloc_req_aead(struct crypt_config *cc,
1474 struct convert_context *ctx)
1475{
1476 if (!ctx->r.req_aead)
1477 ctx->r.req_aead = mempool_alloc(&cc->req_pool, GFP_NOIO);
1478
1479 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1480
1481 /*
1482 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1483 * requests if driver request queue is full.
1484 */
1485 aead_request_set_callback(ctx->r.req_aead,
1486 CRYPTO_TFM_REQ_MAY_BACKLOG,
1487 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
1488}
1489
1490static void crypt_alloc_req(struct crypt_config *cc,
1491 struct convert_context *ctx)
1492{
1493 if (crypt_integrity_aead(cc))
1494 crypt_alloc_req_aead(cc, ctx);
1495 else
1496 crypt_alloc_req_skcipher(cc, ctx);
1497}
1498
1499static void crypt_free_req_skcipher(struct crypt_config *cc,
1500 struct skcipher_request *req, struct bio *base_bio)
1501{
1502 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1503
1504 if ((struct skcipher_request *)(io + 1) != req)
1505 mempool_free(req, &cc->req_pool);
1506}
1507
1508static void crypt_free_req_aead(struct crypt_config *cc,
1509 struct aead_request *req, struct bio *base_bio)
1510{
1511 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1512
1513 if ((struct aead_request *)(io + 1) != req)
1514 mempool_free(req, &cc->req_pool);
1515}
1516
1517static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1518{
1519 if (crypt_integrity_aead(cc))
1520 crypt_free_req_aead(cc, req, base_bio);
1521 else
1522 crypt_free_req_skcipher(cc, req, base_bio);
1523}
1524
1525/*
1526 * Encrypt / decrypt data from one bio to another one (can be the same one)
1527 */
1528static blk_status_t crypt_convert(struct crypt_config *cc,
1529 struct convert_context *ctx, bool atomic)
1530{
1531 unsigned int tag_offset = 0;
1532 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1533 int r;
1534
1535 atomic_set(&ctx->cc_pending, 1);
1536
1537 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1538
1539 crypt_alloc_req(cc, ctx);
1540 atomic_inc(&ctx->cc_pending);
1541
1542 if (crypt_integrity_aead(cc))
1543 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
1544 else
1545 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
1546
1547 switch (r) {
1548 /*
1549 * The request was queued by a crypto driver
1550 * but the driver request queue is full, let's wait.
1551 */
1552 case -EBUSY:
1553 wait_for_completion(&ctx->restart);
1554 reinit_completion(&ctx->restart);
1555 fallthrough;
1556 /*
1557 * The request is queued and processed asynchronously,
1558 * completion function kcryptd_async_done() will be called.
1559 */
1560 case -EINPROGRESS:
1561 ctx->r.req = NULL;
1562 ctx->cc_sector += sector_step;
1563 tag_offset++;
1564 continue;
1565 /*
1566 * The request was already processed (synchronously).
1567 */
1568 case 0:
1569 atomic_dec(&ctx->cc_pending);
1570 ctx->cc_sector += sector_step;
1571 tag_offset++;
1572 if (!atomic)
1573 cond_resched();
1574 continue;
1575 /*
1576 * There was a data integrity error.
1577 */
1578 case -EBADMSG:
1579 atomic_dec(&ctx->cc_pending);
1580 return BLK_STS_PROTECTION;
1581 /*
1582 * There was an error while processing the request.
1583 */
1584 default:
1585 atomic_dec(&ctx->cc_pending);
1586 return BLK_STS_IOERR;
1587 }
1588 }
1589
1590 return 0;
1591}
1592
1593static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1594
1595/*
1596 * Generate a new unfragmented bio with the given size
1597 * This should never violate the device limitations (but only because
1598 * max_segment_size is being constrained to PAGE_SIZE).
1599 *
1600 * This function may be called concurrently. If we allocate from the mempool
1601 * concurrently, there is a possibility of deadlock. For example, if we have
1602 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1603 * the mempool concurrently, it may deadlock in a situation where both processes
1604 * have allocated 128 pages and the mempool is exhausted.
1605 *
1606 * In order to avoid this scenario we allocate the pages under a mutex.
1607 *
1608 * In order to not degrade performance with excessive locking, we try
1609 * non-blocking allocations without a mutex first but on failure we fallback
1610 * to blocking allocations with a mutex.
1611 */
1612static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
1613{
1614 struct crypt_config *cc = io->cc;
1615 struct bio *clone;
1616 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1617 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1618 unsigned i, len, remaining_size;
1619 struct page *page;
1620
1621retry:
1622 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1623 mutex_lock(&cc->bio_alloc_lock);
1624
1625 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs);
1626 if (!clone)
1627 goto out;
1628
1629 clone_init(io, clone);
1630
1631 remaining_size = size;
1632
1633 for (i = 0; i < nr_iovecs; i++) {
1634 page = mempool_alloc(&cc->page_pool, gfp_mask);
1635 if (!page) {
1636 crypt_free_buffer_pages(cc, clone);
1637 bio_put(clone);
1638 gfp_mask |= __GFP_DIRECT_RECLAIM;
1639 goto retry;
1640 }
1641
1642 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
1643
1644 bio_add_page(clone, page, len, 0);
1645
1646 remaining_size -= len;
1647 }
1648
1649 /* Allocate space for integrity tags */
1650 if (dm_crypt_integrity_io_alloc(io, clone)) {
1651 crypt_free_buffer_pages(cc, clone);
1652 bio_put(clone);
1653 clone = NULL;
1654 }
1655out:
1656 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1657 mutex_unlock(&cc->bio_alloc_lock);
1658
1659 return clone;
1660}
1661
1662static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1663{
1664 struct bio_vec *bv;
1665 struct bvec_iter_all iter_all;
1666
1667 bio_for_each_segment_all(bv, clone, iter_all) {
1668 BUG_ON(!bv->bv_page);
1669 mempool_free(bv->bv_page, &cc->page_pool);
1670 }
1671}
1672
1673static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1674 struct bio *bio, sector_t sector)
1675{
1676 io->cc = cc;
1677 io->base_bio = bio;
1678 io->sector = sector;
1679 io->error = 0;
1680 io->ctx.r.req = NULL;
1681 io->integrity_metadata = NULL;
1682 io->integrity_metadata_from_pool = false;
1683 atomic_set(&io->io_pending, 0);
1684}
1685
1686static void crypt_inc_pending(struct dm_crypt_io *io)
1687{
1688 atomic_inc(&io->io_pending);
1689}
1690
1691/*
1692 * One of the bios was finished. Check for completion of
1693 * the whole request and correctly clean up the buffer.
1694 */
1695static void crypt_dec_pending(struct dm_crypt_io *io)
1696{
1697 struct crypt_config *cc = io->cc;
1698 struct bio *base_bio = io->base_bio;
1699 blk_status_t error = io->error;
1700
1701 if (!atomic_dec_and_test(&io->io_pending))
1702 return;
1703
1704 if (io->ctx.r.req)
1705 crypt_free_req(cc, io->ctx.r.req, base_bio);
1706
1707 if (unlikely(io->integrity_metadata_from_pool))
1708 mempool_free(io->integrity_metadata, &io->cc->tag_pool);
1709 else
1710 kfree(io->integrity_metadata);
1711
1712 base_bio->bi_status = error;
1713 bio_endio(base_bio);
1714}
1715
1716/*
1717 * kcryptd/kcryptd_io:
1718 *
1719 * Needed because it would be very unwise to do decryption in an
1720 * interrupt context.
1721 *
1722 * kcryptd performs the actual encryption or decryption.
1723 *
1724 * kcryptd_io performs the IO submission.
1725 *
1726 * They must be separated as otherwise the final stages could be
1727 * starved by new requests which can block in the first stages due
1728 * to memory allocation.
1729 *
1730 * The work is done per CPU global for all dm-crypt instances.
1731 * They should not depend on each other and do not block.
1732 */
1733static void crypt_endio(struct bio *clone)
1734{
1735 struct dm_crypt_io *io = clone->bi_private;
1736 struct crypt_config *cc = io->cc;
1737 unsigned rw = bio_data_dir(clone);
1738 blk_status_t error;
1739
1740 /*
1741 * free the processed pages
1742 */
1743 if (rw == WRITE)
1744 crypt_free_buffer_pages(cc, clone);
1745
1746 error = clone->bi_status;
1747 bio_put(clone);
1748
1749 if (rw == READ && !error) {
1750 kcryptd_queue_crypt(io);
1751 return;
1752 }
1753
1754 if (unlikely(error))
1755 io->error = error;
1756
1757 crypt_dec_pending(io);
1758}
1759
1760static void clone_init(struct dm_crypt_io *io, struct bio *clone)
1761{
1762 struct crypt_config *cc = io->cc;
1763
1764 clone->bi_private = io;
1765 clone->bi_end_io = crypt_endio;
1766 bio_set_dev(clone, cc->dev->bdev);
1767 clone->bi_opf = io->base_bio->bi_opf;
1768}
1769
1770static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1771{
1772 struct crypt_config *cc = io->cc;
1773 struct bio *clone;
1774
1775 /*
1776 * We need the original biovec array in order to decrypt
1777 * the whole bio data *afterwards* -- thanks to immutable
1778 * biovecs we don't need to worry about the block layer
1779 * modifying the biovec array; so leverage bio_clone_fast().
1780 */
1781 clone = bio_clone_fast(io->base_bio, gfp, &cc->bs);
1782 if (!clone)
1783 return 1;
1784
1785 crypt_inc_pending(io);
1786
1787 clone_init(io, clone);
1788 clone->bi_iter.bi_sector = cc->start + io->sector;
1789
1790 if (dm_crypt_integrity_io_alloc(io, clone)) {
1791 crypt_dec_pending(io);
1792 bio_put(clone);
1793 return 1;
1794 }
1795
1796 submit_bio_noacct(clone);
1797 return 0;
1798}
1799
1800static void kcryptd_io_read_work(struct work_struct *work)
1801{
1802 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1803
1804 crypt_inc_pending(io);
1805 if (kcryptd_io_read(io, GFP_NOIO))
1806 io->error = BLK_STS_RESOURCE;
1807 crypt_dec_pending(io);
1808}
1809
1810static void kcryptd_queue_read(struct dm_crypt_io *io)
1811{
1812 struct crypt_config *cc = io->cc;
1813
1814 INIT_WORK(&io->work, kcryptd_io_read_work);
1815 queue_work(cc->io_queue, &io->work);
1816}
1817
1818static void kcryptd_io_write(struct dm_crypt_io *io)
1819{
1820 struct bio *clone = io->ctx.bio_out;
1821
1822 submit_bio_noacct(clone);
1823}
1824
1825#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1826
1827static int dmcrypt_write(void *data)
1828{
1829 struct crypt_config *cc = data;
1830 struct dm_crypt_io *io;
1831
1832 while (1) {
1833 struct rb_root write_tree;
1834 struct blk_plug plug;
1835
1836 spin_lock_irq(&cc->write_thread_lock);
1837continue_locked:
1838
1839 if (!RB_EMPTY_ROOT(&cc->write_tree))
1840 goto pop_from_list;
1841
1842 set_current_state(TASK_INTERRUPTIBLE);
1843
1844 spin_unlock_irq(&cc->write_thread_lock);
1845
1846 if (unlikely(kthread_should_stop())) {
1847 set_current_state(TASK_RUNNING);
1848 break;
1849 }
1850
1851 schedule();
1852
1853 set_current_state(TASK_RUNNING);
1854 spin_lock_irq(&cc->write_thread_lock);
1855 goto continue_locked;
1856
1857pop_from_list:
1858 write_tree = cc->write_tree;
1859 cc->write_tree = RB_ROOT;
1860 spin_unlock_irq(&cc->write_thread_lock);
1861
1862 BUG_ON(rb_parent(write_tree.rb_node));
1863
1864 /*
1865 * Note: we cannot walk the tree here with rb_next because
1866 * the structures may be freed when kcryptd_io_write is called.
1867 */
1868 blk_start_plug(&plug);
1869 do {
1870 io = crypt_io_from_node(rb_first(&write_tree));
1871 rb_erase(&io->rb_node, &write_tree);
1872 kcryptd_io_write(io);
1873 } while (!RB_EMPTY_ROOT(&write_tree));
1874 blk_finish_plug(&plug);
1875 }
1876 return 0;
1877}
1878
1879static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1880{
1881 struct bio *clone = io->ctx.bio_out;
1882 struct crypt_config *cc = io->cc;
1883 unsigned long flags;
1884 sector_t sector;
1885 struct rb_node **rbp, *parent;
1886
1887 if (unlikely(io->error)) {
1888 crypt_free_buffer_pages(cc, clone);
1889 bio_put(clone);
1890 crypt_dec_pending(io);
1891 return;
1892 }
1893
1894 /* crypt_convert should have filled the clone bio */
1895 BUG_ON(io->ctx.iter_out.bi_size);
1896
1897 clone->bi_iter.bi_sector = cc->start + io->sector;
1898
1899 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
1900 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
1901 submit_bio_noacct(clone);
1902 return;
1903 }
1904
1905 spin_lock_irqsave(&cc->write_thread_lock, flags);
1906 if (RB_EMPTY_ROOT(&cc->write_tree))
1907 wake_up_process(cc->write_thread);
1908 rbp = &cc->write_tree.rb_node;
1909 parent = NULL;
1910 sector = io->sector;
1911 while (*rbp) {
1912 parent = *rbp;
1913 if (sector < crypt_io_from_node(parent)->sector)
1914 rbp = &(*rbp)->rb_left;
1915 else
1916 rbp = &(*rbp)->rb_right;
1917 }
1918 rb_link_node(&io->rb_node, parent, rbp);
1919 rb_insert_color(&io->rb_node, &cc->write_tree);
1920 spin_unlock_irqrestore(&cc->write_thread_lock, flags);
1921}
1922
1923static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
1924 struct convert_context *ctx)
1925
1926{
1927 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
1928 return false;
1929
1930 /*
1931 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
1932 * constraints so they do not need to be issued inline by
1933 * kcryptd_crypt_write_convert().
1934 */
1935 switch (bio_op(ctx->bio_in)) {
1936 case REQ_OP_WRITE:
1937 case REQ_OP_WRITE_SAME:
1938 case REQ_OP_WRITE_ZEROES:
1939 return true;
1940 default:
1941 return false;
1942 }
1943}
1944
1945static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
1946{
1947 struct crypt_config *cc = io->cc;
1948 struct convert_context *ctx = &io->ctx;
1949 struct bio *clone;
1950 int crypt_finished;
1951 sector_t sector = io->sector;
1952 blk_status_t r;
1953
1954 /*
1955 * Prevent io from disappearing until this function completes.
1956 */
1957 crypt_inc_pending(io);
1958 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector);
1959
1960 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1961 if (unlikely(!clone)) {
1962 io->error = BLK_STS_IOERR;
1963 goto dec;
1964 }
1965
1966 io->ctx.bio_out = clone;
1967 io->ctx.iter_out = clone->bi_iter;
1968
1969 sector += bio_sectors(clone);
1970
1971 crypt_inc_pending(io);
1972 r = crypt_convert(cc, ctx,
1973 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags));
1974 if (r)
1975 io->error = r;
1976 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
1977 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
1978 /* Wait for completion signaled by kcryptd_async_done() */
1979 wait_for_completion(&ctx->restart);
1980 crypt_finished = 1;
1981 }
1982
1983 /* Encryption was already finished, submit io now */
1984 if (crypt_finished) {
1985 kcryptd_crypt_write_io_submit(io, 0);
1986 io->sector = sector;
1987 }
1988
1989dec:
1990 crypt_dec_pending(io);
1991}
1992
1993static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
1994{
1995 crypt_dec_pending(io);
1996}
1997
1998static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
1999{
2000 struct crypt_config *cc = io->cc;
2001 blk_status_t r;
2002
2003 crypt_inc_pending(io);
2004
2005 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
2006 io->sector);
2007
2008 r = crypt_convert(cc, &io->ctx,
2009 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags));
2010 if (r)
2011 io->error = r;
2012
2013 if (atomic_dec_and_test(&io->ctx.cc_pending))
2014 kcryptd_crypt_read_done(io);
2015
2016 crypt_dec_pending(io);
2017}
2018
2019static void kcryptd_async_done(struct crypto_async_request *async_req,
2020 int error)
2021{
2022 struct dm_crypt_request *dmreq = async_req->data;
2023 struct convert_context *ctx = dmreq->ctx;
2024 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
2025 struct crypt_config *cc = io->cc;
2026
2027 /*
2028 * A request from crypto driver backlog is going to be processed now,
2029 * finish the completion and continue in crypt_convert().
2030 * (Callback will be called for the second time for this request.)
2031 */
2032 if (error == -EINPROGRESS) {
2033 complete(&ctx->restart);
2034 return;
2035 }
2036
2037 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
2038 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
2039
2040 if (error == -EBADMSG) {
2041 char b[BDEVNAME_SIZE];
2042 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b),
2043 (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)));
2044 io->error = BLK_STS_PROTECTION;
2045 } else if (error < 0)
2046 io->error = BLK_STS_IOERR;
2047
2048 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
2049
2050 if (!atomic_dec_and_test(&ctx->cc_pending))
2051 return;
2052
2053 /*
2054 * The request is fully completed: for inline writes, let
2055 * kcryptd_crypt_write_convert() do the IO submission.
2056 */
2057 if (bio_data_dir(io->base_bio) == READ) {
2058 kcryptd_crypt_read_done(io);
2059 return;
2060 }
2061
2062 if (kcryptd_crypt_write_inline(cc, ctx)) {
2063 complete(&ctx->restart);
2064 return;
2065 }
2066
2067 kcryptd_crypt_write_io_submit(io, 1);
2068}
2069
2070static void kcryptd_crypt(struct work_struct *work)
2071{
2072 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2073
2074 if (bio_data_dir(io->base_bio) == READ)
2075 kcryptd_crypt_read_convert(io);
2076 else
2077 kcryptd_crypt_write_convert(io);
2078}
2079
2080static void kcryptd_crypt_tasklet(unsigned long work)
2081{
2082 kcryptd_crypt((struct work_struct *)work);
2083}
2084
2085static void kcryptd_queue_crypt(struct dm_crypt_io *io)
2086{
2087 struct crypt_config *cc = io->cc;
2088
2089 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
2090 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
2091 if (in_irq()) {
2092 /* Crypto API's "skcipher_walk_first() refuses to work in hard IRQ context */
2093 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work);
2094 tasklet_schedule(&io->tasklet);
2095 return;
2096 }
2097
2098 kcryptd_crypt(&io->work);
2099 return;
2100 }
2101
2102 INIT_WORK(&io->work, kcryptd_crypt);
2103 queue_work(cc->crypt_queue, &io->work);
2104}
2105
2106static void crypt_free_tfms_aead(struct crypt_config *cc)
2107{
2108 if (!cc->cipher_tfm.tfms_aead)
2109 return;
2110
2111 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2112 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
2113 cc->cipher_tfm.tfms_aead[0] = NULL;
2114 }
2115
2116 kfree(cc->cipher_tfm.tfms_aead);
2117 cc->cipher_tfm.tfms_aead = NULL;
2118}
2119
2120static void crypt_free_tfms_skcipher(struct crypt_config *cc)
2121{
2122 unsigned i;
2123
2124 if (!cc->cipher_tfm.tfms)
2125 return;
2126
2127 for (i = 0; i < cc->tfms_count; i++)
2128 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
2129 crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
2130 cc->cipher_tfm.tfms[i] = NULL;
2131 }
2132
2133 kfree(cc->cipher_tfm.tfms);
2134 cc->cipher_tfm.tfms = NULL;
2135}
2136
2137static void crypt_free_tfms(struct crypt_config *cc)
2138{
2139 if (crypt_integrity_aead(cc))
2140 crypt_free_tfms_aead(cc);
2141 else
2142 crypt_free_tfms_skcipher(cc);
2143}
2144
2145static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
2146{
2147 unsigned i;
2148 int err;
2149
2150 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count,
2151 sizeof(struct crypto_skcipher *),
2152 GFP_KERNEL);
2153 if (!cc->cipher_tfm.tfms)
2154 return -ENOMEM;
2155
2156 for (i = 0; i < cc->tfms_count; i++) {
2157 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 0);
2158 if (IS_ERR(cc->cipher_tfm.tfms[i])) {
2159 err = PTR_ERR(cc->cipher_tfm.tfms[i]);
2160 crypt_free_tfms(cc);
2161 return err;
2162 }
2163 }
2164
2165 /*
2166 * dm-crypt performance can vary greatly depending on which crypto
2167 * algorithm implementation is used. Help people debug performance
2168 * problems by logging the ->cra_driver_name.
2169 */
2170 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2171 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
2172 return 0;
2173}
2174
2175static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
2176{
2177 int err;
2178
2179 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
2180 if (!cc->cipher_tfm.tfms)
2181 return -ENOMEM;
2182
2183 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 0);
2184 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2185 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
2186 crypt_free_tfms(cc);
2187 return err;
2188 }
2189
2190 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2191 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
2192 return 0;
2193}
2194
2195static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
2196{
2197 if (crypt_integrity_aead(cc))
2198 return crypt_alloc_tfms_aead(cc, ciphermode);
2199 else
2200 return crypt_alloc_tfms_skcipher(cc, ciphermode);
2201}
2202
2203static unsigned crypt_subkey_size(struct crypt_config *cc)
2204{
2205 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
2206}
2207
2208static unsigned crypt_authenckey_size(struct crypt_config *cc)
2209{
2210 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
2211}
2212
2213/*
2214 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
2215 * the key must be for some reason in special format.
2216 * This funcion converts cc->key to this special format.
2217 */
2218static void crypt_copy_authenckey(char *p, const void *key,
2219 unsigned enckeylen, unsigned authkeylen)
2220{
2221 struct crypto_authenc_key_param *param;
2222 struct rtattr *rta;
2223
2224 rta = (struct rtattr *)p;
2225 param = RTA_DATA(rta);
2226 param->enckeylen = cpu_to_be32(enckeylen);
2227 rta->rta_len = RTA_LENGTH(sizeof(*param));
2228 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
2229 p += RTA_SPACE(sizeof(*param));
2230 memcpy(p, key + enckeylen, authkeylen);
2231 p += authkeylen;
2232 memcpy(p, key, enckeylen);
2233}
2234
2235static int crypt_setkey(struct crypt_config *cc)
2236{
2237 unsigned subkey_size;
2238 int err = 0, i, r;
2239
2240 /* Ignore extra keys (which are used for IV etc) */
2241 subkey_size = crypt_subkey_size(cc);
2242
2243 if (crypt_integrity_hmac(cc)) {
2244 if (subkey_size < cc->key_mac_size)
2245 return -EINVAL;
2246
2247 crypt_copy_authenckey(cc->authenc_key, cc->key,
2248 subkey_size - cc->key_mac_size,
2249 cc->key_mac_size);
2250 }
2251
2252 for (i = 0; i < cc->tfms_count; i++) {
2253 if (crypt_integrity_hmac(cc))
2254 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2255 cc->authenc_key, crypt_authenckey_size(cc));
2256 else if (crypt_integrity_aead(cc))
2257 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2258 cc->key + (i * subkey_size),
2259 subkey_size);
2260 else
2261 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
2262 cc->key + (i * subkey_size),
2263 subkey_size);
2264 if (r)
2265 err = r;
2266 }
2267
2268 if (crypt_integrity_hmac(cc))
2269 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
2270
2271 return err;
2272}
2273
2274#ifdef CONFIG_KEYS
2275
2276static bool contains_whitespace(const char *str)
2277{
2278 while (*str)
2279 if (isspace(*str++))
2280 return true;
2281 return false;
2282}
2283
2284static int set_key_user(struct crypt_config *cc, struct key *key)
2285{
2286 const struct user_key_payload *ukp;
2287
2288 ukp = user_key_payload_locked(key);
2289 if (!ukp)
2290 return -EKEYREVOKED;
2291
2292 if (cc->key_size != ukp->datalen)
2293 return -EINVAL;
2294
2295 memcpy(cc->key, ukp->data, cc->key_size);
2296
2297 return 0;
2298}
2299
2300#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
2301static int set_key_encrypted(struct crypt_config *cc, struct key *key)
2302{
2303 const struct encrypted_key_payload *ekp;
2304
2305 ekp = key->payload.data[0];
2306 if (!ekp)
2307 return -EKEYREVOKED;
2308
2309 if (cc->key_size != ekp->decrypted_datalen)
2310 return -EINVAL;
2311
2312 memcpy(cc->key, ekp->decrypted_data, cc->key_size);
2313
2314 return 0;
2315}
2316#endif /* CONFIG_ENCRYPTED_KEYS */
2317
2318static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2319{
2320 char *new_key_string, *key_desc;
2321 int ret;
2322 struct key_type *type;
2323 struct key *key;
2324 int (*set_key)(struct crypt_config *cc, struct key *key);
2325
2326 /*
2327 * Reject key_string with whitespace. dm core currently lacks code for
2328 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2329 */
2330 if (contains_whitespace(key_string)) {
2331 DMERR("whitespace chars not allowed in key string");
2332 return -EINVAL;
2333 }
2334
2335 /* look for next ':' separating key_type from key_description */
2336 key_desc = strpbrk(key_string, ":");
2337 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2338 return -EINVAL;
2339
2340 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
2341 type = &key_type_logon;
2342 set_key = set_key_user;
2343 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
2344 type = &key_type_user;
2345 set_key = set_key_user;
2346#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
2347 } else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
2348 type = &key_type_encrypted;
2349 set_key = set_key_encrypted;
2350#endif
2351 } else {
2352 return -EINVAL;
2353 }
2354
2355 new_key_string = kstrdup(key_string, GFP_KERNEL);
2356 if (!new_key_string)
2357 return -ENOMEM;
2358
2359 key = request_key(type, key_desc + 1, NULL);
2360 if (IS_ERR(key)) {
2361 kfree_sensitive(new_key_string);
2362 return PTR_ERR(key);
2363 }
2364
2365 down_read(&key->sem);
2366
2367 ret = set_key(cc, key);
2368 if (ret < 0) {
2369 up_read(&key->sem);
2370 key_put(key);
2371 kfree_sensitive(new_key_string);
2372 return ret;
2373 }
2374
2375 up_read(&key->sem);
2376 key_put(key);
2377
2378 /* clear the flag since following operations may invalidate previously valid key */
2379 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2380
2381 ret = crypt_setkey(cc);
2382
2383 if (!ret) {
2384 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2385 kfree_sensitive(cc->key_string);
2386 cc->key_string = new_key_string;
2387 } else
2388 kfree_sensitive(new_key_string);
2389
2390 return ret;
2391}
2392
2393static int get_key_size(char **key_string)
2394{
2395 char *colon, dummy;
2396 int ret;
2397
2398 if (*key_string[0] != ':')
2399 return strlen(*key_string) >> 1;
2400
2401 /* look for next ':' in key string */
2402 colon = strpbrk(*key_string + 1, ":");
2403 if (!colon)
2404 return -EINVAL;
2405
2406 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2407 return -EINVAL;
2408
2409 *key_string = colon;
2410
2411 /* remaining key string should be :<logon|user>:<key_desc> */
2412
2413 return ret;
2414}
2415
2416#else
2417
2418static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2419{
2420 return -EINVAL;
2421}
2422
2423static int get_key_size(char **key_string)
2424{
2425 return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1;
2426}
2427
2428#endif /* CONFIG_KEYS */
2429
2430static int crypt_set_key(struct crypt_config *cc, char *key)
2431{
2432 int r = -EINVAL;
2433 int key_string_len = strlen(key);
2434
2435 /* Hyphen (which gives a key_size of zero) means there is no key. */
2436 if (!cc->key_size && strcmp(key, "-"))
2437 goto out;
2438
2439 /* ':' means the key is in kernel keyring, short-circuit normal key processing */
2440 if (key[0] == ':') {
2441 r = crypt_set_keyring_key(cc, key + 1);
2442 goto out;
2443 }
2444
2445 /* clear the flag since following operations may invalidate previously valid key */
2446 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2447
2448 /* wipe references to any kernel keyring key */
2449 kfree_sensitive(cc->key_string);
2450 cc->key_string = NULL;
2451
2452 /* Decode key from its hex representation. */
2453 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2454 goto out;
2455
2456 r = crypt_setkey(cc);
2457 if (!r)
2458 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2459
2460out:
2461 /* Hex key string not needed after here, so wipe it. */
2462 memset(key, '0', key_string_len);
2463
2464 return r;
2465}
2466
2467static int crypt_wipe_key(struct crypt_config *cc)
2468{
2469 int r;
2470
2471 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2472 get_random_bytes(&cc->key, cc->key_size);
2473
2474 /* Wipe IV private keys */
2475 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2476 r = cc->iv_gen_ops->wipe(cc);
2477 if (r)
2478 return r;
2479 }
2480
2481 kfree_sensitive(cc->key_string);
2482 cc->key_string = NULL;
2483 r = crypt_setkey(cc);
2484 memset(&cc->key, 0, cc->key_size * sizeof(u8));
2485
2486 return r;
2487}
2488
2489static void crypt_calculate_pages_per_client(void)
2490{
2491 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
2492
2493 if (!dm_crypt_clients_n)
2494 return;
2495
2496 pages /= dm_crypt_clients_n;
2497 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
2498 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
2499 dm_crypt_pages_per_client = pages;
2500}
2501
2502static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
2503{
2504 struct crypt_config *cc = pool_data;
2505 struct page *page;
2506
2507 if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) &&
2508 likely(gfp_mask & __GFP_NORETRY))
2509 return NULL;
2510
2511 page = alloc_page(gfp_mask);
2512 if (likely(page != NULL))
2513 percpu_counter_add(&cc->n_allocated_pages, 1);
2514
2515 return page;
2516}
2517
2518static void crypt_page_free(void *page, void *pool_data)
2519{
2520 struct crypt_config *cc = pool_data;
2521
2522 __free_page(page);
2523 percpu_counter_sub(&cc->n_allocated_pages, 1);
2524}
2525
2526static void crypt_dtr(struct dm_target *ti)
2527{
2528 struct crypt_config *cc = ti->private;
2529
2530 ti->private = NULL;
2531
2532 if (!cc)
2533 return;
2534
2535 if (cc->write_thread)
2536 kthread_stop(cc->write_thread);
2537
2538 if (cc->io_queue)
2539 destroy_workqueue(cc->io_queue);
2540 if (cc->crypt_queue)
2541 destroy_workqueue(cc->crypt_queue);
2542
2543 crypt_free_tfms(cc);
2544
2545 bioset_exit(&cc->bs);
2546
2547 mempool_exit(&cc->page_pool);
2548 mempool_exit(&cc->req_pool);
2549 mempool_exit(&cc->tag_pool);
2550
2551 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
2552 percpu_counter_destroy(&cc->n_allocated_pages);
2553
2554 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2555 cc->iv_gen_ops->dtr(cc);
2556
2557 if (cc->dev)
2558 dm_put_device(ti, cc->dev);
2559
2560 kfree_sensitive(cc->cipher_string);
2561 kfree_sensitive(cc->key_string);
2562 kfree_sensitive(cc->cipher_auth);
2563 kfree_sensitive(cc->authenc_key);
2564
2565 mutex_destroy(&cc->bio_alloc_lock);
2566
2567 /* Must zero key material before freeing */
2568 kfree_sensitive(cc);
2569
2570 spin_lock(&dm_crypt_clients_lock);
2571 WARN_ON(!dm_crypt_clients_n);
2572 dm_crypt_clients_n--;
2573 crypt_calculate_pages_per_client();
2574 spin_unlock(&dm_crypt_clients_lock);
2575}
2576
2577static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2578{
2579 struct crypt_config *cc = ti->private;
2580
2581 if (crypt_integrity_aead(cc))
2582 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2583 else
2584 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2585
2586 if (cc->iv_size)
2587 /* at least a 64 bit sector number should fit in our buffer */
2588 cc->iv_size = max(cc->iv_size,
2589 (unsigned int)(sizeof(u64) / sizeof(u8)));
2590 else if (ivmode) {
2591 DMWARN("Selected cipher does not support IVs");
2592 ivmode = NULL;
2593 }
2594
2595 /* Choose ivmode, see comments at iv code. */
2596 if (ivmode == NULL)
2597 cc->iv_gen_ops = NULL;
2598 else if (strcmp(ivmode, "plain") == 0)
2599 cc->iv_gen_ops = &crypt_iv_plain_ops;
2600 else if (strcmp(ivmode, "plain64") == 0)
2601 cc->iv_gen_ops = &crypt_iv_plain64_ops;
2602 else if (strcmp(ivmode, "plain64be") == 0)
2603 cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2604 else if (strcmp(ivmode, "essiv") == 0)
2605 cc->iv_gen_ops = &crypt_iv_essiv_ops;
2606 else if (strcmp(ivmode, "benbi") == 0)
2607 cc->iv_gen_ops = &crypt_iv_benbi_ops;
2608 else if (strcmp(ivmode, "null") == 0)
2609 cc->iv_gen_ops = &crypt_iv_null_ops;
2610 else if (strcmp(ivmode, "eboiv") == 0)
2611 cc->iv_gen_ops = &crypt_iv_eboiv_ops;
2612 else if (strcmp(ivmode, "elephant") == 0) {
2613 cc->iv_gen_ops = &crypt_iv_elephant_ops;
2614 cc->key_parts = 2;
2615 cc->key_extra_size = cc->key_size / 2;
2616 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
2617 return -EINVAL;
2618 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
2619 } else if (strcmp(ivmode, "lmk") == 0) {
2620 cc->iv_gen_ops = &crypt_iv_lmk_ops;
2621 /*
2622 * Version 2 and 3 is recognised according
2623 * to length of provided multi-key string.
2624 * If present (version 3), last key is used as IV seed.
2625 * All keys (including IV seed) are always the same size.
2626 */
2627 if (cc->key_size % cc->key_parts) {
2628 cc->key_parts++;
2629 cc->key_extra_size = cc->key_size / cc->key_parts;
2630 }
2631 } else if (strcmp(ivmode, "tcw") == 0) {
2632 cc->iv_gen_ops = &crypt_iv_tcw_ops;
2633 cc->key_parts += 2; /* IV + whitening */
2634 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2635 } else if (strcmp(ivmode, "random") == 0) {
2636 cc->iv_gen_ops = &crypt_iv_random_ops;
2637 /* Need storage space in integrity fields. */
2638 cc->integrity_iv_size = cc->iv_size;
2639 } else {
2640 ti->error = "Invalid IV mode";
2641 return -EINVAL;
2642 }
2643
2644 return 0;
2645}
2646
2647/*
2648 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2649 * The HMAC is needed to calculate tag size (HMAC digest size).
2650 * This should be probably done by crypto-api calls (once available...)
2651 */
2652static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2653{
2654 char *start, *end, *mac_alg = NULL;
2655 struct crypto_ahash *mac;
2656
2657 if (!strstarts(cipher_api, "authenc("))
2658 return 0;
2659
2660 start = strchr(cipher_api, '(');
2661 end = strchr(cipher_api, ',');
2662 if (!start || !end || ++start > end)
2663 return -EINVAL;
2664
2665 mac_alg = kzalloc(end - start + 1, GFP_KERNEL);
2666 if (!mac_alg)
2667 return -ENOMEM;
2668 strncpy(mac_alg, start, end - start);
2669
2670 mac = crypto_alloc_ahash(mac_alg, 0, 0);
2671 kfree(mac_alg);
2672
2673 if (IS_ERR(mac))
2674 return PTR_ERR(mac);
2675
2676 cc->key_mac_size = crypto_ahash_digestsize(mac);
2677 crypto_free_ahash(mac);
2678
2679 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2680 if (!cc->authenc_key)
2681 return -ENOMEM;
2682
2683 return 0;
2684}
2685
2686static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2687 char **ivmode, char **ivopts)
2688{
2689 struct crypt_config *cc = ti->private;
2690 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
2691 int ret = -EINVAL;
2692
2693 cc->tfms_count = 1;
2694
2695 /*
2696 * New format (capi: prefix)
2697 * capi:cipher_api_spec-iv:ivopts
2698 */
2699 tmp = &cipher_in[strlen("capi:")];
2700
2701 /* Separate IV options if present, it can contain another '-' in hash name */
2702 *ivopts = strrchr(tmp, ':');
2703 if (*ivopts) {
2704 **ivopts = '\0';
2705 (*ivopts)++;
2706 }
2707 /* Parse IV mode */
2708 *ivmode = strrchr(tmp, '-');
2709 if (*ivmode) {
2710 **ivmode = '\0';
2711 (*ivmode)++;
2712 }
2713 /* The rest is crypto API spec */
2714 cipher_api = tmp;
2715
2716 /* Alloc AEAD, can be used only in new format. */
2717 if (crypt_integrity_aead(cc)) {
2718 ret = crypt_ctr_auth_cipher(cc, cipher_api);
2719 if (ret < 0) {
2720 ti->error = "Invalid AEAD cipher spec";
2721 return -ENOMEM;
2722 }
2723 }
2724
2725 if (*ivmode && !strcmp(*ivmode, "lmk"))
2726 cc->tfms_count = 64;
2727
2728 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2729 if (!*ivopts) {
2730 ti->error = "Digest algorithm missing for ESSIV mode";
2731 return -EINVAL;
2732 }
2733 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
2734 cipher_api, *ivopts);
2735 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2736 ti->error = "Cannot allocate cipher string";
2737 return -ENOMEM;
2738 }
2739 cipher_api = buf;
2740 }
2741
2742 cc->key_parts = cc->tfms_count;
2743
2744 /* Allocate cipher */
2745 ret = crypt_alloc_tfms(cc, cipher_api);
2746 if (ret < 0) {
2747 ti->error = "Error allocating crypto tfm";
2748 return ret;
2749 }
2750
2751 if (crypt_integrity_aead(cc))
2752 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2753 else
2754 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2755
2756 return 0;
2757}
2758
2759static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2760 char **ivmode, char **ivopts)
2761{
2762 struct crypt_config *cc = ti->private;
2763 char *tmp, *cipher, *chainmode, *keycount;
2764 char *cipher_api = NULL;
2765 int ret = -EINVAL;
2766 char dummy;
2767
2768 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2769 ti->error = "Bad cipher specification";
2770 return -EINVAL;
2771 }
2772
2773 /*
2774 * Legacy dm-crypt cipher specification
2775 * cipher[:keycount]-mode-iv:ivopts
2776 */
2777 tmp = cipher_in;
2778 keycount = strsep(&tmp, "-");
2779 cipher = strsep(&keycount, ":");
2780
2781 if (!keycount)
2782 cc->tfms_count = 1;
2783 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
2784 !is_power_of_2(cc->tfms_count)) {
2785 ti->error = "Bad cipher key count specification";
2786 return -EINVAL;
2787 }
2788 cc->key_parts = cc->tfms_count;
2789
2790 chainmode = strsep(&tmp, "-");
2791 *ivmode = strsep(&tmp, ":");
2792 *ivopts = tmp;
2793
2794 /*
2795 * For compatibility with the original dm-crypt mapping format, if
2796 * only the cipher name is supplied, use cbc-plain.
2797 */
2798 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
2799 chainmode = "cbc";
2800 *ivmode = "plain";
2801 }
2802
2803 if (strcmp(chainmode, "ecb") && !*ivmode) {
2804 ti->error = "IV mechanism required";
2805 return -EINVAL;
2806 }
2807
2808 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
2809 if (!cipher_api)
2810 goto bad_mem;
2811
2812 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2813 if (!*ivopts) {
2814 ti->error = "Digest algorithm missing for ESSIV mode";
2815 kfree(cipher_api);
2816 return -EINVAL;
2817 }
2818 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2819 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
2820 } else {
2821 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2822 "%s(%s)", chainmode, cipher);
2823 }
2824 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2825 kfree(cipher_api);
2826 goto bad_mem;
2827 }
2828
2829 /* Allocate cipher */
2830 ret = crypt_alloc_tfms(cc, cipher_api);
2831 if (ret < 0) {
2832 ti->error = "Error allocating crypto tfm";
2833 kfree(cipher_api);
2834 return ret;
2835 }
2836 kfree(cipher_api);
2837
2838 return 0;
2839bad_mem:
2840 ti->error = "Cannot allocate cipher strings";
2841 return -ENOMEM;
2842}
2843
2844static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
2845{
2846 struct crypt_config *cc = ti->private;
2847 char *ivmode = NULL, *ivopts = NULL;
2848 int ret;
2849
2850 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
2851 if (!cc->cipher_string) {
2852 ti->error = "Cannot allocate cipher strings";
2853 return -ENOMEM;
2854 }
2855
2856 if (strstarts(cipher_in, "capi:"))
2857 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
2858 else
2859 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
2860 if (ret)
2861 return ret;
2862
2863 /* Initialize IV */
2864 ret = crypt_ctr_ivmode(ti, ivmode);
2865 if (ret < 0)
2866 return ret;
2867
2868 /* Initialize and set key */
2869 ret = crypt_set_key(cc, key);
2870 if (ret < 0) {
2871 ti->error = "Error decoding and setting key";
2872 return ret;
2873 }
2874
2875 /* Allocate IV */
2876 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
2877 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
2878 if (ret < 0) {
2879 ti->error = "Error creating IV";
2880 return ret;
2881 }
2882 }
2883
2884 /* Initialize IV (set keys for ESSIV etc) */
2885 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
2886 ret = cc->iv_gen_ops->init(cc);
2887 if (ret < 0) {
2888 ti->error = "Error initialising IV";
2889 return ret;
2890 }
2891 }
2892
2893 /* wipe the kernel key payload copy */
2894 if (cc->key_string)
2895 memset(cc->key, 0, cc->key_size * sizeof(u8));
2896
2897 return ret;
2898}
2899
2900static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
2901{
2902 struct crypt_config *cc = ti->private;
2903 struct dm_arg_set as;
2904 static const struct dm_arg _args[] = {
2905 {0, 8, "Invalid number of feature args"},
2906 };
2907 unsigned int opt_params, val;
2908 const char *opt_string, *sval;
2909 char dummy;
2910 int ret;
2911
2912 /* Optional parameters */
2913 as.argc = argc;
2914 as.argv = argv;
2915
2916 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
2917 if (ret)
2918 return ret;
2919
2920 while (opt_params--) {
2921 opt_string = dm_shift_arg(&as);
2922 if (!opt_string) {
2923 ti->error = "Not enough feature arguments";
2924 return -EINVAL;
2925 }
2926
2927 if (!strcasecmp(opt_string, "allow_discards"))
2928 ti->num_discard_bios = 1;
2929
2930 else if (!strcasecmp(opt_string, "same_cpu_crypt"))
2931 set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
2932
2933 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
2934 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
2935 else if (!strcasecmp(opt_string, "no_read_workqueue"))
2936 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
2937 else if (!strcasecmp(opt_string, "no_write_workqueue"))
2938 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
2939 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
2940 if (val == 0 || val > MAX_TAG_SIZE) {
2941 ti->error = "Invalid integrity arguments";
2942 return -EINVAL;
2943 }
2944 cc->on_disk_tag_size = val;
2945 sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
2946 if (!strcasecmp(sval, "aead")) {
2947 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
2948 } else if (strcasecmp(sval, "none")) {
2949 ti->error = "Unknown integrity profile";
2950 return -EINVAL;
2951 }
2952
2953 cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
2954 if (!cc->cipher_auth)
2955 return -ENOMEM;
2956 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
2957 if (cc->sector_size < (1 << SECTOR_SHIFT) ||
2958 cc->sector_size > 4096 ||
2959 (cc->sector_size & (cc->sector_size - 1))) {
2960 ti->error = "Invalid feature value for sector_size";
2961 return -EINVAL;
2962 }
2963 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
2964 ti->error = "Device size is not multiple of sector_size feature";
2965 return -EINVAL;
2966 }
2967 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
2968 } else if (!strcasecmp(opt_string, "iv_large_sectors"))
2969 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
2970 else {
2971 ti->error = "Invalid feature arguments";
2972 return -EINVAL;
2973 }
2974 }
2975
2976 return 0;
2977}
2978
2979#ifdef CONFIG_BLK_DEV_ZONED
2980
2981static int crypt_report_zones(struct dm_target *ti,
2982 struct dm_report_zones_args *args, unsigned int nr_zones)
2983{
2984 struct crypt_config *cc = ti->private;
2985 sector_t sector = cc->start + dm_target_offset(ti, args->next_sector);
2986
2987 args->start = cc->start;
2988 return blkdev_report_zones(cc->dev->bdev, sector, nr_zones,
2989 dm_report_zones_cb, args);
2990}
2991
2992#endif
2993
2994/*
2995 * Construct an encryption mapping:
2996 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
2997 */
2998static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2999{
3000 struct crypt_config *cc;
3001 const char *devname = dm_table_device_name(ti->table);
3002 int key_size;
3003 unsigned int align_mask;
3004 unsigned long long tmpll;
3005 int ret;
3006 size_t iv_size_padding, additional_req_size;
3007 char dummy;
3008
3009 if (argc < 5) {
3010 ti->error = "Not enough arguments";
3011 return -EINVAL;
3012 }
3013
3014 key_size = get_key_size(&argv[1]);
3015 if (key_size < 0) {
3016 ti->error = "Cannot parse key size";
3017 return -EINVAL;
3018 }
3019
3020 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
3021 if (!cc) {
3022 ti->error = "Cannot allocate encryption context";
3023 return -ENOMEM;
3024 }
3025 cc->key_size = key_size;
3026 cc->sector_size = (1 << SECTOR_SHIFT);
3027 cc->sector_shift = 0;
3028
3029 ti->private = cc;
3030
3031 spin_lock(&dm_crypt_clients_lock);
3032 dm_crypt_clients_n++;
3033 crypt_calculate_pages_per_client();
3034 spin_unlock(&dm_crypt_clients_lock);
3035
3036 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
3037 if (ret < 0)
3038 goto bad;
3039
3040 /* Optional parameters need to be read before cipher constructor */
3041 if (argc > 5) {
3042 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
3043 if (ret)
3044 goto bad;
3045 }
3046
3047 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
3048 if (ret < 0)
3049 goto bad;
3050
3051 if (crypt_integrity_aead(cc)) {
3052 cc->dmreq_start = sizeof(struct aead_request);
3053 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
3054 align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
3055 } else {
3056 cc->dmreq_start = sizeof(struct skcipher_request);
3057 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
3058 align_mask = crypto_skcipher_alignmask(any_tfm(cc));
3059 }
3060 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
3061
3062 if (align_mask < CRYPTO_MINALIGN) {
3063 /* Allocate the padding exactly */
3064 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
3065 & align_mask;
3066 } else {
3067 /*
3068 * If the cipher requires greater alignment than kmalloc
3069 * alignment, we don't know the exact position of the
3070 * initialization vector. We must assume worst case.
3071 */
3072 iv_size_padding = align_mask;
3073 }
3074
3075 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */
3076 additional_req_size = sizeof(struct dm_crypt_request) +
3077 iv_size_padding + cc->iv_size +
3078 cc->iv_size +
3079 sizeof(uint64_t) +
3080 sizeof(unsigned int);
3081
3082 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
3083 if (ret) {
3084 ti->error = "Cannot allocate crypt request mempool";
3085 goto bad;
3086 }
3087
3088 cc->per_bio_data_size = ti->per_io_data_size =
3089 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
3090 ARCH_KMALLOC_MINALIGN);
3091
3092 ret = mempool_init(&cc->page_pool, BIO_MAX_PAGES, crypt_page_alloc, crypt_page_free, cc);
3093 if (ret) {
3094 ti->error = "Cannot allocate page mempool";
3095 goto bad;
3096 }
3097
3098 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
3099 if (ret) {
3100 ti->error = "Cannot allocate crypt bioset";
3101 goto bad;
3102 }
3103
3104 mutex_init(&cc->bio_alloc_lock);
3105
3106 ret = -EINVAL;
3107 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
3108 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
3109 ti->error = "Invalid iv_offset sector";
3110 goto bad;
3111 }
3112 cc->iv_offset = tmpll;
3113
3114 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
3115 if (ret) {
3116 ti->error = "Device lookup failed";
3117 goto bad;
3118 }
3119
3120 ret = -EINVAL;
3121 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
3122 ti->error = "Invalid device sector";
3123 goto bad;
3124 }
3125 cc->start = tmpll;
3126
3127 /*
3128 * For zoned block devices, we need to preserve the issuer write
3129 * ordering. To do so, disable write workqueues and force inline
3130 * encryption completion.
3131 */
3132 if (bdev_is_zoned(cc->dev->bdev)) {
3133 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3134 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
3135 }
3136
3137 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
3138 ret = crypt_integrity_ctr(cc, ti);
3139 if (ret)
3140 goto bad;
3141
3142 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
3143 if (!cc->tag_pool_max_sectors)
3144 cc->tag_pool_max_sectors = 1;
3145
3146 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
3147 cc->tag_pool_max_sectors * cc->on_disk_tag_size);
3148 if (ret) {
3149 ti->error = "Cannot allocate integrity tags mempool";
3150 goto bad;
3151 }
3152
3153 cc->tag_pool_max_sectors <<= cc->sector_shift;
3154 }
3155
3156 ret = -ENOMEM;
3157 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname);
3158 if (!cc->io_queue) {
3159 ti->error = "Couldn't create kcryptd io queue";
3160 goto bad;
3161 }
3162
3163 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3164 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
3165 1, devname);
3166 else
3167 cc->crypt_queue = alloc_workqueue("kcryptd/%s",
3168 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
3169 num_online_cpus(), devname);
3170 if (!cc->crypt_queue) {
3171 ti->error = "Couldn't create kcryptd queue";
3172 goto bad;
3173 }
3174
3175 spin_lock_init(&cc->write_thread_lock);
3176 cc->write_tree = RB_ROOT;
3177
3178 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
3179 if (IS_ERR(cc->write_thread)) {
3180 ret = PTR_ERR(cc->write_thread);
3181 cc->write_thread = NULL;
3182 ti->error = "Couldn't spawn write thread";
3183 goto bad;
3184 }
3185 wake_up_process(cc->write_thread);
3186
3187 ti->num_flush_bios = 1;
3188
3189 return 0;
3190
3191bad:
3192 crypt_dtr(ti);
3193 return ret;
3194}
3195
3196static int crypt_map(struct dm_target *ti, struct bio *bio)
3197{
3198 struct dm_crypt_io *io;
3199 struct crypt_config *cc = ti->private;
3200
3201 /*
3202 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
3203 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
3204 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
3205 */
3206 if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
3207 bio_op(bio) == REQ_OP_DISCARD)) {
3208 bio_set_dev(bio, cc->dev->bdev);
3209 if (bio_sectors(bio))
3210 bio->bi_iter.bi_sector = cc->start +
3211 dm_target_offset(ti, bio->bi_iter.bi_sector);
3212 return DM_MAPIO_REMAPPED;
3213 }
3214
3215 /*
3216 * Check if bio is too large, split as needed.
3217 */
3218 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) &&
3219 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
3220 dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT));
3221
3222 /*
3223 * Ensure that bio is a multiple of internal sector encryption size
3224 * and is aligned to this size as defined in IO hints.
3225 */
3226 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
3227 return DM_MAPIO_KILL;
3228
3229 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
3230 return DM_MAPIO_KILL;
3231
3232 io = dm_per_bio_data(bio, cc->per_bio_data_size);
3233 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
3234
3235 if (cc->on_disk_tag_size) {
3236 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
3237
3238 if (unlikely(tag_len > KMALLOC_MAX_SIZE) ||
3239 unlikely(!(io->integrity_metadata = kmalloc(tag_len,
3240 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) {
3241 if (bio_sectors(bio) > cc->tag_pool_max_sectors)
3242 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
3243 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
3244 io->integrity_metadata_from_pool = true;
3245 }
3246 }
3247
3248 if (crypt_integrity_aead(cc))
3249 io->ctx.r.req_aead = (struct aead_request *)(io + 1);
3250 else
3251 io->ctx.r.req = (struct skcipher_request *)(io + 1);
3252
3253 if (bio_data_dir(io->base_bio) == READ) {
3254 if (kcryptd_io_read(io, GFP_NOWAIT))
3255 kcryptd_queue_read(io);
3256 } else
3257 kcryptd_queue_crypt(io);
3258
3259 return DM_MAPIO_SUBMITTED;
3260}
3261
3262static void crypt_status(struct dm_target *ti, status_type_t type,
3263 unsigned status_flags, char *result, unsigned maxlen)
3264{
3265 struct crypt_config *cc = ti->private;
3266 unsigned i, sz = 0;
3267 int num_feature_args = 0;
3268
3269 switch (type) {
3270 case STATUSTYPE_INFO:
3271 result[0] = '\0';
3272 break;
3273
3274 case STATUSTYPE_TABLE:
3275 DMEMIT("%s ", cc->cipher_string);
3276
3277 if (cc->key_size > 0) {
3278 if (cc->key_string)
3279 DMEMIT(":%u:%s", cc->key_size, cc->key_string);
3280 else
3281 for (i = 0; i < cc->key_size; i++)
3282 DMEMIT("%02x", cc->key[i]);
3283 } else
3284 DMEMIT("-");
3285
3286 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
3287 cc->dev->name, (unsigned long long)cc->start);
3288
3289 num_feature_args += !!ti->num_discard_bios;
3290 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3291 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3292 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3293 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3294 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
3295 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3296 if (cc->on_disk_tag_size)
3297 num_feature_args++;
3298 if (num_feature_args) {
3299 DMEMIT(" %d", num_feature_args);
3300 if (ti->num_discard_bios)
3301 DMEMIT(" allow_discards");
3302 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3303 DMEMIT(" same_cpu_crypt");
3304 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
3305 DMEMIT(" submit_from_crypt_cpus");
3306 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
3307 DMEMIT(" no_read_workqueue");
3308 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
3309 DMEMIT(" no_write_workqueue");
3310 if (cc->on_disk_tag_size)
3311 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
3312 if (cc->sector_size != (1 << SECTOR_SHIFT))
3313 DMEMIT(" sector_size:%d", cc->sector_size);
3314 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
3315 DMEMIT(" iv_large_sectors");
3316 }
3317
3318 break;
3319 }
3320}
3321
3322static void crypt_postsuspend(struct dm_target *ti)
3323{
3324 struct crypt_config *cc = ti->private;
3325
3326 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3327}
3328
3329static int crypt_preresume(struct dm_target *ti)
3330{
3331 struct crypt_config *cc = ti->private;
3332
3333 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
3334 DMERR("aborting resume - crypt key is not set.");
3335 return -EAGAIN;
3336 }
3337
3338 return 0;
3339}
3340
3341static void crypt_resume(struct dm_target *ti)
3342{
3343 struct crypt_config *cc = ti->private;
3344
3345 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3346}
3347
3348/* Message interface
3349 * key set <key>
3350 * key wipe
3351 */
3352static int crypt_message(struct dm_target *ti, unsigned argc, char **argv,
3353 char *result, unsigned maxlen)
3354{
3355 struct crypt_config *cc = ti->private;
3356 int key_size, ret = -EINVAL;
3357
3358 if (argc < 2)
3359 goto error;
3360
3361 if (!strcasecmp(argv[0], "key")) {
3362 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
3363 DMWARN("not suspended during key manipulation.");
3364 return -EINVAL;
3365 }
3366 if (argc == 3 && !strcasecmp(argv[1], "set")) {
3367 /* The key size may not be changed. */
3368 key_size = get_key_size(&argv[2]);
3369 if (key_size < 0 || cc->key_size != key_size) {
3370 memset(argv[2], '0', strlen(argv[2]));
3371 return -EINVAL;
3372 }
3373
3374 ret = crypt_set_key(cc, argv[2]);
3375 if (ret)
3376 return ret;
3377 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
3378 ret = cc->iv_gen_ops->init(cc);
3379 /* wipe the kernel key payload copy */
3380 if (cc->key_string)
3381 memset(cc->key, 0, cc->key_size * sizeof(u8));
3382 return ret;
3383 }
3384 if (argc == 2 && !strcasecmp(argv[1], "wipe"))
3385 return crypt_wipe_key(cc);
3386 }
3387
3388error:
3389 DMWARN("unrecognised message received.");
3390 return -EINVAL;
3391}
3392
3393static int crypt_iterate_devices(struct dm_target *ti,
3394 iterate_devices_callout_fn fn, void *data)
3395{
3396 struct crypt_config *cc = ti->private;
3397
3398 return fn(ti, cc->dev, cc->start, ti->len, data);
3399}
3400
3401static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
3402{
3403 struct crypt_config *cc = ti->private;
3404
3405 /*
3406 * Unfortunate constraint that is required to avoid the potential
3407 * for exceeding underlying device's max_segments limits -- due to
3408 * crypt_alloc_buffer() possibly allocating pages for the encryption
3409 * bio that are not as physically contiguous as the original bio.
3410 */
3411 limits->max_segment_size = PAGE_SIZE;
3412
3413 limits->logical_block_size =
3414 max_t(unsigned, limits->logical_block_size, cc->sector_size);
3415 limits->physical_block_size =
3416 max_t(unsigned, limits->physical_block_size, cc->sector_size);
3417 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size);
3418}
3419
3420static struct target_type crypt_target = {
3421 .name = "crypt",
3422 .version = {1, 22, 0},
3423 .module = THIS_MODULE,
3424 .ctr = crypt_ctr,
3425 .dtr = crypt_dtr,
3426#ifdef CONFIG_BLK_DEV_ZONED
3427 .features = DM_TARGET_ZONED_HM,
3428 .report_zones = crypt_report_zones,
3429#endif
3430 .map = crypt_map,
3431 .status = crypt_status,
3432 .postsuspend = crypt_postsuspend,
3433 .preresume = crypt_preresume,
3434 .resume = crypt_resume,
3435 .message = crypt_message,
3436 .iterate_devices = crypt_iterate_devices,
3437 .io_hints = crypt_io_hints,
3438};
3439
3440static int __init dm_crypt_init(void)
3441{
3442 int r;
3443
3444 r = dm_register_target(&crypt_target);
3445 if (r < 0)
3446 DMERR("register failed %d", r);
3447
3448 return r;
3449}
3450
3451static void __exit dm_crypt_exit(void)
3452{
3453 dm_unregister_target(&crypt_target);
3454}
3455
3456module_init(dm_crypt_init);
3457module_exit(dm_crypt_exit);
3458
3459MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3460MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3461MODULE_LICENSE("GPL");
1/*
2 * Copyright (C) 2003 Christophe Saout <christophe@saout.de>
3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
4 * Copyright (C) 2006-2009 Red Hat, Inc. All rights reserved.
5 *
6 * This file is released under the GPL.
7 */
8
9#include <linux/completion.h>
10#include <linux/err.h>
11#include <linux/module.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/bio.h>
15#include <linux/blkdev.h>
16#include <linux/mempool.h>
17#include <linux/slab.h>
18#include <linux/crypto.h>
19#include <linux/workqueue.h>
20#include <linux/backing-dev.h>
21#include <linux/percpu.h>
22#include <linux/atomic.h>
23#include <linux/scatterlist.h>
24#include <asm/page.h>
25#include <asm/unaligned.h>
26#include <crypto/hash.h>
27#include <crypto/md5.h>
28#include <crypto/algapi.h>
29
30#include <linux/device-mapper.h>
31
32#define DM_MSG_PREFIX "crypt"
33
34/*
35 * context holding the current state of a multi-part conversion
36 */
37struct convert_context {
38 struct completion restart;
39 struct bio *bio_in;
40 struct bio *bio_out;
41 unsigned int offset_in;
42 unsigned int offset_out;
43 unsigned int idx_in;
44 unsigned int idx_out;
45 sector_t sector;
46 atomic_t pending;
47};
48
49/*
50 * per bio private data
51 */
52struct dm_crypt_io {
53 struct dm_target *target;
54 struct bio *base_bio;
55 struct work_struct work;
56
57 struct convert_context ctx;
58
59 atomic_t pending;
60 int error;
61 sector_t sector;
62 struct dm_crypt_io *base_io;
63};
64
65struct dm_crypt_request {
66 struct convert_context *ctx;
67 struct scatterlist sg_in;
68 struct scatterlist sg_out;
69 sector_t iv_sector;
70};
71
72struct crypt_config;
73
74struct crypt_iv_operations {
75 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
76 const char *opts);
77 void (*dtr)(struct crypt_config *cc);
78 int (*init)(struct crypt_config *cc);
79 int (*wipe)(struct crypt_config *cc);
80 int (*generator)(struct crypt_config *cc, u8 *iv,
81 struct dm_crypt_request *dmreq);
82 int (*post)(struct crypt_config *cc, u8 *iv,
83 struct dm_crypt_request *dmreq);
84};
85
86struct iv_essiv_private {
87 struct crypto_hash *hash_tfm;
88 u8 *salt;
89};
90
91struct iv_benbi_private {
92 int shift;
93};
94
95#define LMK_SEED_SIZE 64 /* hash + 0 */
96struct iv_lmk_private {
97 struct crypto_shash *hash_tfm;
98 u8 *seed;
99};
100
101/*
102 * Crypt: maps a linear range of a block device
103 * and encrypts / decrypts at the same time.
104 */
105enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
106
107/*
108 * Duplicated per-CPU state for cipher.
109 */
110struct crypt_cpu {
111 struct ablkcipher_request *req;
112 /* ESSIV: struct crypto_cipher *essiv_tfm */
113 void *iv_private;
114 struct crypto_ablkcipher *tfms[0];
115};
116
117/*
118 * The fields in here must be read only after initialization,
119 * changing state should be in crypt_cpu.
120 */
121struct crypt_config {
122 struct dm_dev *dev;
123 sector_t start;
124
125 /*
126 * pool for per bio private data, crypto requests and
127 * encryption requeusts/buffer pages
128 */
129 mempool_t *io_pool;
130 mempool_t *req_pool;
131 mempool_t *page_pool;
132 struct bio_set *bs;
133
134 struct workqueue_struct *io_queue;
135 struct workqueue_struct *crypt_queue;
136
137 char *cipher;
138 char *cipher_string;
139
140 struct crypt_iv_operations *iv_gen_ops;
141 union {
142 struct iv_essiv_private essiv;
143 struct iv_benbi_private benbi;
144 struct iv_lmk_private lmk;
145 } iv_gen_private;
146 sector_t iv_offset;
147 unsigned int iv_size;
148
149 /*
150 * Duplicated per cpu state. Access through
151 * per_cpu_ptr() only.
152 */
153 struct crypt_cpu __percpu *cpu;
154 unsigned tfms_count;
155
156 /*
157 * Layout of each crypto request:
158 *
159 * struct ablkcipher_request
160 * context
161 * padding
162 * struct dm_crypt_request
163 * padding
164 * IV
165 *
166 * The padding is added so that dm_crypt_request and the IV are
167 * correctly aligned.
168 */
169 unsigned int dmreq_start;
170
171 unsigned long flags;
172 unsigned int key_size;
173 unsigned int key_parts;
174 u8 key[0];
175};
176
177#define MIN_IOS 16
178#define MIN_POOL_PAGES 32
179#define MIN_BIO_PAGES 8
180
181static struct kmem_cache *_crypt_io_pool;
182
183static void clone_init(struct dm_crypt_io *, struct bio *);
184static void kcryptd_queue_crypt(struct dm_crypt_io *io);
185static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq);
186
187static struct crypt_cpu *this_crypt_config(struct crypt_config *cc)
188{
189 return this_cpu_ptr(cc->cpu);
190}
191
192/*
193 * Use this to access cipher attributes that are the same for each CPU.
194 */
195static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
196{
197 return __this_cpu_ptr(cc->cpu)->tfms[0];
198}
199
200/*
201 * Different IV generation algorithms:
202 *
203 * plain: the initial vector is the 32-bit little-endian version of the sector
204 * number, padded with zeros if necessary.
205 *
206 * plain64: the initial vector is the 64-bit little-endian version of the sector
207 * number, padded with zeros if necessary.
208 *
209 * essiv: "encrypted sector|salt initial vector", the sector number is
210 * encrypted with the bulk cipher using a salt as key. The salt
211 * should be derived from the bulk cipher's key via hashing.
212 *
213 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
214 * (needed for LRW-32-AES and possible other narrow block modes)
215 *
216 * null: the initial vector is always zero. Provides compatibility with
217 * obsolete loop_fish2 devices. Do not use for new devices.
218 *
219 * lmk: Compatible implementation of the block chaining mode used
220 * by the Loop-AES block device encryption system
221 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
222 * It operates on full 512 byte sectors and uses CBC
223 * with an IV derived from the sector number, the data and
224 * optionally extra IV seed.
225 * This means that after decryption the first block
226 * of sector must be tweaked according to decrypted data.
227 * Loop-AES can use three encryption schemes:
228 * version 1: is plain aes-cbc mode
229 * version 2: uses 64 multikey scheme with lmk IV generator
230 * version 3: the same as version 2 with additional IV seed
231 * (it uses 65 keys, last key is used as IV seed)
232 *
233 * plumb: unimplemented, see:
234 * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
235 */
236
237static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
238 struct dm_crypt_request *dmreq)
239{
240 memset(iv, 0, cc->iv_size);
241 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
242
243 return 0;
244}
245
246static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
247 struct dm_crypt_request *dmreq)
248{
249 memset(iv, 0, cc->iv_size);
250 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
251
252 return 0;
253}
254
255/* Initialise ESSIV - compute salt but no local memory allocations */
256static int crypt_iv_essiv_init(struct crypt_config *cc)
257{
258 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
259 struct hash_desc desc;
260 struct scatterlist sg;
261 struct crypto_cipher *essiv_tfm;
262 int err, cpu;
263
264 sg_init_one(&sg, cc->key, cc->key_size);
265 desc.tfm = essiv->hash_tfm;
266 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
267
268 err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt);
269 if (err)
270 return err;
271
272 for_each_possible_cpu(cpu) {
273 essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private,
274
275 err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
276 crypto_hash_digestsize(essiv->hash_tfm));
277 if (err)
278 return err;
279 }
280
281 return 0;
282}
283
284/* Wipe salt and reset key derived from volume key */
285static int crypt_iv_essiv_wipe(struct crypt_config *cc)
286{
287 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
288 unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
289 struct crypto_cipher *essiv_tfm;
290 int cpu, r, err = 0;
291
292 memset(essiv->salt, 0, salt_size);
293
294 for_each_possible_cpu(cpu) {
295 essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private;
296 r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
297 if (r)
298 err = r;
299 }
300
301 return err;
302}
303
304/* Set up per cpu cipher state */
305static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
306 struct dm_target *ti,
307 u8 *salt, unsigned saltsize)
308{
309 struct crypto_cipher *essiv_tfm;
310 int err;
311
312 /* Setup the essiv_tfm with the given salt */
313 essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
314 if (IS_ERR(essiv_tfm)) {
315 ti->error = "Error allocating crypto tfm for ESSIV";
316 return essiv_tfm;
317 }
318
319 if (crypto_cipher_blocksize(essiv_tfm) !=
320 crypto_ablkcipher_ivsize(any_tfm(cc))) {
321 ti->error = "Block size of ESSIV cipher does "
322 "not match IV size of block cipher";
323 crypto_free_cipher(essiv_tfm);
324 return ERR_PTR(-EINVAL);
325 }
326
327 err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
328 if (err) {
329 ti->error = "Failed to set key for ESSIV cipher";
330 crypto_free_cipher(essiv_tfm);
331 return ERR_PTR(err);
332 }
333
334 return essiv_tfm;
335}
336
337static void crypt_iv_essiv_dtr(struct crypt_config *cc)
338{
339 int cpu;
340 struct crypt_cpu *cpu_cc;
341 struct crypto_cipher *essiv_tfm;
342 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
343
344 crypto_free_hash(essiv->hash_tfm);
345 essiv->hash_tfm = NULL;
346
347 kzfree(essiv->salt);
348 essiv->salt = NULL;
349
350 for_each_possible_cpu(cpu) {
351 cpu_cc = per_cpu_ptr(cc->cpu, cpu);
352 essiv_tfm = cpu_cc->iv_private;
353
354 if (essiv_tfm)
355 crypto_free_cipher(essiv_tfm);
356
357 cpu_cc->iv_private = NULL;
358 }
359}
360
361static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
362 const char *opts)
363{
364 struct crypto_cipher *essiv_tfm = NULL;
365 struct crypto_hash *hash_tfm = NULL;
366 u8 *salt = NULL;
367 int err, cpu;
368
369 if (!opts) {
370 ti->error = "Digest algorithm missing for ESSIV mode";
371 return -EINVAL;
372 }
373
374 /* Allocate hash algorithm */
375 hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC);
376 if (IS_ERR(hash_tfm)) {
377 ti->error = "Error initializing ESSIV hash";
378 err = PTR_ERR(hash_tfm);
379 goto bad;
380 }
381
382 salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL);
383 if (!salt) {
384 ti->error = "Error kmallocing salt storage in ESSIV";
385 err = -ENOMEM;
386 goto bad;
387 }
388
389 cc->iv_gen_private.essiv.salt = salt;
390 cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
391
392 for_each_possible_cpu(cpu) {
393 essiv_tfm = setup_essiv_cpu(cc, ti, salt,
394 crypto_hash_digestsize(hash_tfm));
395 if (IS_ERR(essiv_tfm)) {
396 crypt_iv_essiv_dtr(cc);
397 return PTR_ERR(essiv_tfm);
398 }
399 per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm;
400 }
401
402 return 0;
403
404bad:
405 if (hash_tfm && !IS_ERR(hash_tfm))
406 crypto_free_hash(hash_tfm);
407 kfree(salt);
408 return err;
409}
410
411static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
412 struct dm_crypt_request *dmreq)
413{
414 struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private;
415
416 memset(iv, 0, cc->iv_size);
417 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
418 crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
419
420 return 0;
421}
422
423static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
424 const char *opts)
425{
426 unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
427 int log = ilog2(bs);
428
429 /* we need to calculate how far we must shift the sector count
430 * to get the cipher block count, we use this shift in _gen */
431
432 if (1 << log != bs) {
433 ti->error = "cypher blocksize is not a power of 2";
434 return -EINVAL;
435 }
436
437 if (log > 9) {
438 ti->error = "cypher blocksize is > 512";
439 return -EINVAL;
440 }
441
442 cc->iv_gen_private.benbi.shift = 9 - log;
443
444 return 0;
445}
446
447static void crypt_iv_benbi_dtr(struct crypt_config *cc)
448{
449}
450
451static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
452 struct dm_crypt_request *dmreq)
453{
454 __be64 val;
455
456 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
457
458 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
459 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
460
461 return 0;
462}
463
464static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
465 struct dm_crypt_request *dmreq)
466{
467 memset(iv, 0, cc->iv_size);
468
469 return 0;
470}
471
472static void crypt_iv_lmk_dtr(struct crypt_config *cc)
473{
474 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
475
476 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
477 crypto_free_shash(lmk->hash_tfm);
478 lmk->hash_tfm = NULL;
479
480 kzfree(lmk->seed);
481 lmk->seed = NULL;
482}
483
484static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
485 const char *opts)
486{
487 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
488
489 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
490 if (IS_ERR(lmk->hash_tfm)) {
491 ti->error = "Error initializing LMK hash";
492 return PTR_ERR(lmk->hash_tfm);
493 }
494
495 /* No seed in LMK version 2 */
496 if (cc->key_parts == cc->tfms_count) {
497 lmk->seed = NULL;
498 return 0;
499 }
500
501 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
502 if (!lmk->seed) {
503 crypt_iv_lmk_dtr(cc);
504 ti->error = "Error kmallocing seed storage in LMK";
505 return -ENOMEM;
506 }
507
508 return 0;
509}
510
511static int crypt_iv_lmk_init(struct crypt_config *cc)
512{
513 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
514 int subkey_size = cc->key_size / cc->key_parts;
515
516 /* LMK seed is on the position of LMK_KEYS + 1 key */
517 if (lmk->seed)
518 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
519 crypto_shash_digestsize(lmk->hash_tfm));
520
521 return 0;
522}
523
524static int crypt_iv_lmk_wipe(struct crypt_config *cc)
525{
526 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
527
528 if (lmk->seed)
529 memset(lmk->seed, 0, LMK_SEED_SIZE);
530
531 return 0;
532}
533
534static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
535 struct dm_crypt_request *dmreq,
536 u8 *data)
537{
538 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
539 struct {
540 struct shash_desc desc;
541 char ctx[crypto_shash_descsize(lmk->hash_tfm)];
542 } sdesc;
543 struct md5_state md5state;
544 u32 buf[4];
545 int i, r;
546
547 sdesc.desc.tfm = lmk->hash_tfm;
548 sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
549
550 r = crypto_shash_init(&sdesc.desc);
551 if (r)
552 return r;
553
554 if (lmk->seed) {
555 r = crypto_shash_update(&sdesc.desc, lmk->seed, LMK_SEED_SIZE);
556 if (r)
557 return r;
558 }
559
560 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
561 r = crypto_shash_update(&sdesc.desc, data + 16, 16 * 31);
562 if (r)
563 return r;
564
565 /* Sector is cropped to 56 bits here */
566 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
567 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
568 buf[2] = cpu_to_le32(4024);
569 buf[3] = 0;
570 r = crypto_shash_update(&sdesc.desc, (u8 *)buf, sizeof(buf));
571 if (r)
572 return r;
573
574 /* No MD5 padding here */
575 r = crypto_shash_export(&sdesc.desc, &md5state);
576 if (r)
577 return r;
578
579 for (i = 0; i < MD5_HASH_WORDS; i++)
580 __cpu_to_le32s(&md5state.hash[i]);
581 memcpy(iv, &md5state.hash, cc->iv_size);
582
583 return 0;
584}
585
586static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
587 struct dm_crypt_request *dmreq)
588{
589 u8 *src;
590 int r = 0;
591
592 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
593 src = kmap_atomic(sg_page(&dmreq->sg_in), KM_USER0);
594 r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset);
595 kunmap_atomic(src, KM_USER0);
596 } else
597 memset(iv, 0, cc->iv_size);
598
599 return r;
600}
601
602static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
603 struct dm_crypt_request *dmreq)
604{
605 u8 *dst;
606 int r;
607
608 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
609 return 0;
610
611 dst = kmap_atomic(sg_page(&dmreq->sg_out), KM_USER0);
612 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + dmreq->sg_out.offset);
613
614 /* Tweak the first block of plaintext sector */
615 if (!r)
616 crypto_xor(dst + dmreq->sg_out.offset, iv, cc->iv_size);
617
618 kunmap_atomic(dst, KM_USER0);
619 return r;
620}
621
622static struct crypt_iv_operations crypt_iv_plain_ops = {
623 .generator = crypt_iv_plain_gen
624};
625
626static struct crypt_iv_operations crypt_iv_plain64_ops = {
627 .generator = crypt_iv_plain64_gen
628};
629
630static struct crypt_iv_operations crypt_iv_essiv_ops = {
631 .ctr = crypt_iv_essiv_ctr,
632 .dtr = crypt_iv_essiv_dtr,
633 .init = crypt_iv_essiv_init,
634 .wipe = crypt_iv_essiv_wipe,
635 .generator = crypt_iv_essiv_gen
636};
637
638static struct crypt_iv_operations crypt_iv_benbi_ops = {
639 .ctr = crypt_iv_benbi_ctr,
640 .dtr = crypt_iv_benbi_dtr,
641 .generator = crypt_iv_benbi_gen
642};
643
644static struct crypt_iv_operations crypt_iv_null_ops = {
645 .generator = crypt_iv_null_gen
646};
647
648static struct crypt_iv_operations crypt_iv_lmk_ops = {
649 .ctr = crypt_iv_lmk_ctr,
650 .dtr = crypt_iv_lmk_dtr,
651 .init = crypt_iv_lmk_init,
652 .wipe = crypt_iv_lmk_wipe,
653 .generator = crypt_iv_lmk_gen,
654 .post = crypt_iv_lmk_post
655};
656
657static void crypt_convert_init(struct crypt_config *cc,
658 struct convert_context *ctx,
659 struct bio *bio_out, struct bio *bio_in,
660 sector_t sector)
661{
662 ctx->bio_in = bio_in;
663 ctx->bio_out = bio_out;
664 ctx->offset_in = 0;
665 ctx->offset_out = 0;
666 ctx->idx_in = bio_in ? bio_in->bi_idx : 0;
667 ctx->idx_out = bio_out ? bio_out->bi_idx : 0;
668 ctx->sector = sector + cc->iv_offset;
669 init_completion(&ctx->restart);
670}
671
672static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
673 struct ablkcipher_request *req)
674{
675 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
676}
677
678static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
679 struct dm_crypt_request *dmreq)
680{
681 return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
682}
683
684static u8 *iv_of_dmreq(struct crypt_config *cc,
685 struct dm_crypt_request *dmreq)
686{
687 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
688 crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
689}
690
691static int crypt_convert_block(struct crypt_config *cc,
692 struct convert_context *ctx,
693 struct ablkcipher_request *req)
694{
695 struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in);
696 struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out);
697 struct dm_crypt_request *dmreq;
698 u8 *iv;
699 int r = 0;
700
701 dmreq = dmreq_of_req(cc, req);
702 iv = iv_of_dmreq(cc, dmreq);
703
704 dmreq->iv_sector = ctx->sector;
705 dmreq->ctx = ctx;
706 sg_init_table(&dmreq->sg_in, 1);
707 sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
708 bv_in->bv_offset + ctx->offset_in);
709
710 sg_init_table(&dmreq->sg_out, 1);
711 sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT,
712 bv_out->bv_offset + ctx->offset_out);
713
714 ctx->offset_in += 1 << SECTOR_SHIFT;
715 if (ctx->offset_in >= bv_in->bv_len) {
716 ctx->offset_in = 0;
717 ctx->idx_in++;
718 }
719
720 ctx->offset_out += 1 << SECTOR_SHIFT;
721 if (ctx->offset_out >= bv_out->bv_len) {
722 ctx->offset_out = 0;
723 ctx->idx_out++;
724 }
725
726 if (cc->iv_gen_ops) {
727 r = cc->iv_gen_ops->generator(cc, iv, dmreq);
728 if (r < 0)
729 return r;
730 }
731
732 ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
733 1 << SECTOR_SHIFT, iv);
734
735 if (bio_data_dir(ctx->bio_in) == WRITE)
736 r = crypto_ablkcipher_encrypt(req);
737 else
738 r = crypto_ablkcipher_decrypt(req);
739
740 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
741 r = cc->iv_gen_ops->post(cc, iv, dmreq);
742
743 return r;
744}
745
746static void kcryptd_async_done(struct crypto_async_request *async_req,
747 int error);
748
749static void crypt_alloc_req(struct crypt_config *cc,
750 struct convert_context *ctx)
751{
752 struct crypt_cpu *this_cc = this_crypt_config(cc);
753 unsigned key_index = ctx->sector & (cc->tfms_count - 1);
754
755 if (!this_cc->req)
756 this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
757
758 ablkcipher_request_set_tfm(this_cc->req, this_cc->tfms[key_index]);
759 ablkcipher_request_set_callback(this_cc->req,
760 CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
761 kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
762}
763
764/*
765 * Encrypt / decrypt data from one bio to another one (can be the same one)
766 */
767static int crypt_convert(struct crypt_config *cc,
768 struct convert_context *ctx)
769{
770 struct crypt_cpu *this_cc = this_crypt_config(cc);
771 int r;
772
773 atomic_set(&ctx->pending, 1);
774
775 while(ctx->idx_in < ctx->bio_in->bi_vcnt &&
776 ctx->idx_out < ctx->bio_out->bi_vcnt) {
777
778 crypt_alloc_req(cc, ctx);
779
780 atomic_inc(&ctx->pending);
781
782 r = crypt_convert_block(cc, ctx, this_cc->req);
783
784 switch (r) {
785 /* async */
786 case -EBUSY:
787 wait_for_completion(&ctx->restart);
788 INIT_COMPLETION(ctx->restart);
789 /* fall through*/
790 case -EINPROGRESS:
791 this_cc->req = NULL;
792 ctx->sector++;
793 continue;
794
795 /* sync */
796 case 0:
797 atomic_dec(&ctx->pending);
798 ctx->sector++;
799 cond_resched();
800 continue;
801
802 /* error */
803 default:
804 atomic_dec(&ctx->pending);
805 return r;
806 }
807 }
808
809 return 0;
810}
811
812static void dm_crypt_bio_destructor(struct bio *bio)
813{
814 struct dm_crypt_io *io = bio->bi_private;
815 struct crypt_config *cc = io->target->private;
816
817 bio_free(bio, cc->bs);
818}
819
820/*
821 * Generate a new unfragmented bio with the given size
822 * This should never violate the device limitations
823 * May return a smaller bio when running out of pages, indicated by
824 * *out_of_pages set to 1.
825 */
826static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size,
827 unsigned *out_of_pages)
828{
829 struct crypt_config *cc = io->target->private;
830 struct bio *clone;
831 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
832 gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM;
833 unsigned i, len;
834 struct page *page;
835
836 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs);
837 if (!clone)
838 return NULL;
839
840 clone_init(io, clone);
841 *out_of_pages = 0;
842
843 for (i = 0; i < nr_iovecs; i++) {
844 page = mempool_alloc(cc->page_pool, gfp_mask);
845 if (!page) {
846 *out_of_pages = 1;
847 break;
848 }
849
850 /*
851 * if additional pages cannot be allocated without waiting,
852 * return a partially allocated bio, the caller will then try
853 * to allocate additional bios while submitting this partial bio
854 */
855 if (i == (MIN_BIO_PAGES - 1))
856 gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT;
857
858 len = (size > PAGE_SIZE) ? PAGE_SIZE : size;
859
860 if (!bio_add_page(clone, page, len, 0)) {
861 mempool_free(page, cc->page_pool);
862 break;
863 }
864
865 size -= len;
866 }
867
868 if (!clone->bi_size) {
869 bio_put(clone);
870 return NULL;
871 }
872
873 return clone;
874}
875
876static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
877{
878 unsigned int i;
879 struct bio_vec *bv;
880
881 for (i = 0; i < clone->bi_vcnt; i++) {
882 bv = bio_iovec_idx(clone, i);
883 BUG_ON(!bv->bv_page);
884 mempool_free(bv->bv_page, cc->page_pool);
885 bv->bv_page = NULL;
886 }
887}
888
889static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti,
890 struct bio *bio, sector_t sector)
891{
892 struct crypt_config *cc = ti->private;
893 struct dm_crypt_io *io;
894
895 io = mempool_alloc(cc->io_pool, GFP_NOIO);
896 io->target = ti;
897 io->base_bio = bio;
898 io->sector = sector;
899 io->error = 0;
900 io->base_io = NULL;
901 atomic_set(&io->pending, 0);
902
903 return io;
904}
905
906static void crypt_inc_pending(struct dm_crypt_io *io)
907{
908 atomic_inc(&io->pending);
909}
910
911/*
912 * One of the bios was finished. Check for completion of
913 * the whole request and correctly clean up the buffer.
914 * If base_io is set, wait for the last fragment to complete.
915 */
916static void crypt_dec_pending(struct dm_crypt_io *io)
917{
918 struct crypt_config *cc = io->target->private;
919 struct bio *base_bio = io->base_bio;
920 struct dm_crypt_io *base_io = io->base_io;
921 int error = io->error;
922
923 if (!atomic_dec_and_test(&io->pending))
924 return;
925
926 mempool_free(io, cc->io_pool);
927
928 if (likely(!base_io))
929 bio_endio(base_bio, error);
930 else {
931 if (error && !base_io->error)
932 base_io->error = error;
933 crypt_dec_pending(base_io);
934 }
935}
936
937/*
938 * kcryptd/kcryptd_io:
939 *
940 * Needed because it would be very unwise to do decryption in an
941 * interrupt context.
942 *
943 * kcryptd performs the actual encryption or decryption.
944 *
945 * kcryptd_io performs the IO submission.
946 *
947 * They must be separated as otherwise the final stages could be
948 * starved by new requests which can block in the first stages due
949 * to memory allocation.
950 *
951 * The work is done per CPU global for all dm-crypt instances.
952 * They should not depend on each other and do not block.
953 */
954static void crypt_endio(struct bio *clone, int error)
955{
956 struct dm_crypt_io *io = clone->bi_private;
957 struct crypt_config *cc = io->target->private;
958 unsigned rw = bio_data_dir(clone);
959
960 if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error))
961 error = -EIO;
962
963 /*
964 * free the processed pages
965 */
966 if (rw == WRITE)
967 crypt_free_buffer_pages(cc, clone);
968
969 bio_put(clone);
970
971 if (rw == READ && !error) {
972 kcryptd_queue_crypt(io);
973 return;
974 }
975
976 if (unlikely(error))
977 io->error = error;
978
979 crypt_dec_pending(io);
980}
981
982static void clone_init(struct dm_crypt_io *io, struct bio *clone)
983{
984 struct crypt_config *cc = io->target->private;
985
986 clone->bi_private = io;
987 clone->bi_end_io = crypt_endio;
988 clone->bi_bdev = cc->dev->bdev;
989 clone->bi_rw = io->base_bio->bi_rw;
990 clone->bi_destructor = dm_crypt_bio_destructor;
991}
992
993static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
994{
995 struct crypt_config *cc = io->target->private;
996 struct bio *base_bio = io->base_bio;
997 struct bio *clone;
998
999 /*
1000 * The block layer might modify the bvec array, so always
1001 * copy the required bvecs because we need the original
1002 * one in order to decrypt the whole bio data *afterwards*.
1003 */
1004 clone = bio_alloc_bioset(gfp, bio_segments(base_bio), cc->bs);
1005 if (!clone)
1006 return 1;
1007
1008 crypt_inc_pending(io);
1009
1010 clone_init(io, clone);
1011 clone->bi_idx = 0;
1012 clone->bi_vcnt = bio_segments(base_bio);
1013 clone->bi_size = base_bio->bi_size;
1014 clone->bi_sector = cc->start + io->sector;
1015 memcpy(clone->bi_io_vec, bio_iovec(base_bio),
1016 sizeof(struct bio_vec) * clone->bi_vcnt);
1017
1018 generic_make_request(clone);
1019 return 0;
1020}
1021
1022static void kcryptd_io_write(struct dm_crypt_io *io)
1023{
1024 struct bio *clone = io->ctx.bio_out;
1025 generic_make_request(clone);
1026}
1027
1028static void kcryptd_io(struct work_struct *work)
1029{
1030 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1031
1032 if (bio_data_dir(io->base_bio) == READ) {
1033 crypt_inc_pending(io);
1034 if (kcryptd_io_read(io, GFP_NOIO))
1035 io->error = -ENOMEM;
1036 crypt_dec_pending(io);
1037 } else
1038 kcryptd_io_write(io);
1039}
1040
1041static void kcryptd_queue_io(struct dm_crypt_io *io)
1042{
1043 struct crypt_config *cc = io->target->private;
1044
1045 INIT_WORK(&io->work, kcryptd_io);
1046 queue_work(cc->io_queue, &io->work);
1047}
1048
1049static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
1050 int error, int async)
1051{
1052 struct bio *clone = io->ctx.bio_out;
1053 struct crypt_config *cc = io->target->private;
1054
1055 if (unlikely(error < 0)) {
1056 crypt_free_buffer_pages(cc, clone);
1057 bio_put(clone);
1058 io->error = -EIO;
1059 crypt_dec_pending(io);
1060 return;
1061 }
1062
1063 /* crypt_convert should have filled the clone bio */
1064 BUG_ON(io->ctx.idx_out < clone->bi_vcnt);
1065
1066 clone->bi_sector = cc->start + io->sector;
1067
1068 if (async)
1069 kcryptd_queue_io(io);
1070 else
1071 generic_make_request(clone);
1072}
1073
1074static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
1075{
1076 struct crypt_config *cc = io->target->private;
1077 struct bio *clone;
1078 struct dm_crypt_io *new_io;
1079 int crypt_finished;
1080 unsigned out_of_pages = 0;
1081 unsigned remaining = io->base_bio->bi_size;
1082 sector_t sector = io->sector;
1083 int r;
1084
1085 /*
1086 * Prevent io from disappearing until this function completes.
1087 */
1088 crypt_inc_pending(io);
1089 crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
1090
1091 /*
1092 * The allocated buffers can be smaller than the whole bio,
1093 * so repeat the whole process until all the data can be handled.
1094 */
1095 while (remaining) {
1096 clone = crypt_alloc_buffer(io, remaining, &out_of_pages);
1097 if (unlikely(!clone)) {
1098 io->error = -ENOMEM;
1099 break;
1100 }
1101
1102 io->ctx.bio_out = clone;
1103 io->ctx.idx_out = 0;
1104
1105 remaining -= clone->bi_size;
1106 sector += bio_sectors(clone);
1107
1108 crypt_inc_pending(io);
1109 r = crypt_convert(cc, &io->ctx);
1110 crypt_finished = atomic_dec_and_test(&io->ctx.pending);
1111
1112 /* Encryption was already finished, submit io now */
1113 if (crypt_finished) {
1114 kcryptd_crypt_write_io_submit(io, r, 0);
1115
1116 /*
1117 * If there was an error, do not try next fragments.
1118 * For async, error is processed in async handler.
1119 */
1120 if (unlikely(r < 0))
1121 break;
1122
1123 io->sector = sector;
1124 }
1125
1126 /*
1127 * Out of memory -> run queues
1128 * But don't wait if split was due to the io size restriction
1129 */
1130 if (unlikely(out_of_pages))
1131 congestion_wait(BLK_RW_ASYNC, HZ/100);
1132
1133 /*
1134 * With async crypto it is unsafe to share the crypto context
1135 * between fragments, so switch to a new dm_crypt_io structure.
1136 */
1137 if (unlikely(!crypt_finished && remaining)) {
1138 new_io = crypt_io_alloc(io->target, io->base_bio,
1139 sector);
1140 crypt_inc_pending(new_io);
1141 crypt_convert_init(cc, &new_io->ctx, NULL,
1142 io->base_bio, sector);
1143 new_io->ctx.idx_in = io->ctx.idx_in;
1144 new_io->ctx.offset_in = io->ctx.offset_in;
1145
1146 /*
1147 * Fragments after the first use the base_io
1148 * pending count.
1149 */
1150 if (!io->base_io)
1151 new_io->base_io = io;
1152 else {
1153 new_io->base_io = io->base_io;
1154 crypt_inc_pending(io->base_io);
1155 crypt_dec_pending(io);
1156 }
1157
1158 io = new_io;
1159 }
1160 }
1161
1162 crypt_dec_pending(io);
1163}
1164
1165static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error)
1166{
1167 if (unlikely(error < 0))
1168 io->error = -EIO;
1169
1170 crypt_dec_pending(io);
1171}
1172
1173static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
1174{
1175 struct crypt_config *cc = io->target->private;
1176 int r = 0;
1177
1178 crypt_inc_pending(io);
1179
1180 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
1181 io->sector);
1182
1183 r = crypt_convert(cc, &io->ctx);
1184
1185 if (atomic_dec_and_test(&io->ctx.pending))
1186 kcryptd_crypt_read_done(io, r);
1187
1188 crypt_dec_pending(io);
1189}
1190
1191static void kcryptd_async_done(struct crypto_async_request *async_req,
1192 int error)
1193{
1194 struct dm_crypt_request *dmreq = async_req->data;
1195 struct convert_context *ctx = dmreq->ctx;
1196 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1197 struct crypt_config *cc = io->target->private;
1198
1199 if (error == -EINPROGRESS) {
1200 complete(&ctx->restart);
1201 return;
1202 }
1203
1204 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
1205 error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq);
1206
1207 mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
1208
1209 if (!atomic_dec_and_test(&ctx->pending))
1210 return;
1211
1212 if (bio_data_dir(io->base_bio) == READ)
1213 kcryptd_crypt_read_done(io, error);
1214 else
1215 kcryptd_crypt_write_io_submit(io, error, 1);
1216}
1217
1218static void kcryptd_crypt(struct work_struct *work)
1219{
1220 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1221
1222 if (bio_data_dir(io->base_bio) == READ)
1223 kcryptd_crypt_read_convert(io);
1224 else
1225 kcryptd_crypt_write_convert(io);
1226}
1227
1228static void kcryptd_queue_crypt(struct dm_crypt_io *io)
1229{
1230 struct crypt_config *cc = io->target->private;
1231
1232 INIT_WORK(&io->work, kcryptd_crypt);
1233 queue_work(cc->crypt_queue, &io->work);
1234}
1235
1236/*
1237 * Decode key from its hex representation
1238 */
1239static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
1240{
1241 char buffer[3];
1242 char *endp;
1243 unsigned int i;
1244
1245 buffer[2] = '\0';
1246
1247 for (i = 0; i < size; i++) {
1248 buffer[0] = *hex++;
1249 buffer[1] = *hex++;
1250
1251 key[i] = (u8)simple_strtoul(buffer, &endp, 16);
1252
1253 if (endp != &buffer[2])
1254 return -EINVAL;
1255 }
1256
1257 if (*hex != '\0')
1258 return -EINVAL;
1259
1260 return 0;
1261}
1262
1263/*
1264 * Encode key into its hex representation
1265 */
1266static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
1267{
1268 unsigned int i;
1269
1270 for (i = 0; i < size; i++) {
1271 sprintf(hex, "%02x", *key);
1272 hex += 2;
1273 key++;
1274 }
1275}
1276
1277static void crypt_free_tfms(struct crypt_config *cc, int cpu)
1278{
1279 struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1280 unsigned i;
1281
1282 for (i = 0; i < cc->tfms_count; i++)
1283 if (cpu_cc->tfms[i] && !IS_ERR(cpu_cc->tfms[i])) {
1284 crypto_free_ablkcipher(cpu_cc->tfms[i]);
1285 cpu_cc->tfms[i] = NULL;
1286 }
1287}
1288
1289static int crypt_alloc_tfms(struct crypt_config *cc, int cpu, char *ciphermode)
1290{
1291 struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1292 unsigned i;
1293 int err;
1294
1295 for (i = 0; i < cc->tfms_count; i++) {
1296 cpu_cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
1297 if (IS_ERR(cpu_cc->tfms[i])) {
1298 err = PTR_ERR(cpu_cc->tfms[i]);
1299 crypt_free_tfms(cc, cpu);
1300 return err;
1301 }
1302 }
1303
1304 return 0;
1305}
1306
1307static int crypt_setkey_allcpus(struct crypt_config *cc)
1308{
1309 unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count);
1310 int cpu, err = 0, i, r;
1311
1312 for_each_possible_cpu(cpu) {
1313 for (i = 0; i < cc->tfms_count; i++) {
1314 r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfms[i],
1315 cc->key + (i * subkey_size), subkey_size);
1316 if (r)
1317 err = r;
1318 }
1319 }
1320
1321 return err;
1322}
1323
1324static int crypt_set_key(struct crypt_config *cc, char *key)
1325{
1326 int r = -EINVAL;
1327 int key_string_len = strlen(key);
1328
1329 /* The key size may not be changed. */
1330 if (cc->key_size != (key_string_len >> 1))
1331 goto out;
1332
1333 /* Hyphen (which gives a key_size of zero) means there is no key. */
1334 if (!cc->key_size && strcmp(key, "-"))
1335 goto out;
1336
1337 if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
1338 goto out;
1339
1340 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1341
1342 r = crypt_setkey_allcpus(cc);
1343
1344out:
1345 /* Hex key string not needed after here, so wipe it. */
1346 memset(key, '0', key_string_len);
1347
1348 return r;
1349}
1350
1351static int crypt_wipe_key(struct crypt_config *cc)
1352{
1353 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1354 memset(&cc->key, 0, cc->key_size * sizeof(u8));
1355
1356 return crypt_setkey_allcpus(cc);
1357}
1358
1359static void crypt_dtr(struct dm_target *ti)
1360{
1361 struct crypt_config *cc = ti->private;
1362 struct crypt_cpu *cpu_cc;
1363 int cpu;
1364
1365 ti->private = NULL;
1366
1367 if (!cc)
1368 return;
1369
1370 if (cc->io_queue)
1371 destroy_workqueue(cc->io_queue);
1372 if (cc->crypt_queue)
1373 destroy_workqueue(cc->crypt_queue);
1374
1375 if (cc->cpu)
1376 for_each_possible_cpu(cpu) {
1377 cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1378 if (cpu_cc->req)
1379 mempool_free(cpu_cc->req, cc->req_pool);
1380 crypt_free_tfms(cc, cpu);
1381 }
1382
1383 if (cc->bs)
1384 bioset_free(cc->bs);
1385
1386 if (cc->page_pool)
1387 mempool_destroy(cc->page_pool);
1388 if (cc->req_pool)
1389 mempool_destroy(cc->req_pool);
1390 if (cc->io_pool)
1391 mempool_destroy(cc->io_pool);
1392
1393 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
1394 cc->iv_gen_ops->dtr(cc);
1395
1396 if (cc->dev)
1397 dm_put_device(ti, cc->dev);
1398
1399 if (cc->cpu)
1400 free_percpu(cc->cpu);
1401
1402 kzfree(cc->cipher);
1403 kzfree(cc->cipher_string);
1404
1405 /* Must zero key material before freeing */
1406 kzfree(cc);
1407}
1408
1409static int crypt_ctr_cipher(struct dm_target *ti,
1410 char *cipher_in, char *key)
1411{
1412 struct crypt_config *cc = ti->private;
1413 char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
1414 char *cipher_api = NULL;
1415 int cpu, ret = -EINVAL;
1416
1417 /* Convert to crypto api definition? */
1418 if (strchr(cipher_in, '(')) {
1419 ti->error = "Bad cipher specification";
1420 return -EINVAL;
1421 }
1422
1423 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
1424 if (!cc->cipher_string)
1425 goto bad_mem;
1426
1427 /*
1428 * Legacy dm-crypt cipher specification
1429 * cipher[:keycount]-mode-iv:ivopts
1430 */
1431 tmp = cipher_in;
1432 keycount = strsep(&tmp, "-");
1433 cipher = strsep(&keycount, ":");
1434
1435 if (!keycount)
1436 cc->tfms_count = 1;
1437 else if (sscanf(keycount, "%u", &cc->tfms_count) != 1 ||
1438 !is_power_of_2(cc->tfms_count)) {
1439 ti->error = "Bad cipher key count specification";
1440 return -EINVAL;
1441 }
1442 cc->key_parts = cc->tfms_count;
1443
1444 cc->cipher = kstrdup(cipher, GFP_KERNEL);
1445 if (!cc->cipher)
1446 goto bad_mem;
1447
1448 chainmode = strsep(&tmp, "-");
1449 ivopts = strsep(&tmp, "-");
1450 ivmode = strsep(&ivopts, ":");
1451
1452 if (tmp)
1453 DMWARN("Ignoring unexpected additional cipher options");
1454
1455 cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)) +
1456 cc->tfms_count * sizeof(*(cc->cpu->tfms)),
1457 __alignof__(struct crypt_cpu));
1458 if (!cc->cpu) {
1459 ti->error = "Cannot allocate per cpu state";
1460 goto bad_mem;
1461 }
1462
1463 /*
1464 * For compatibility with the original dm-crypt mapping format, if
1465 * only the cipher name is supplied, use cbc-plain.
1466 */
1467 if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) {
1468 chainmode = "cbc";
1469 ivmode = "plain";
1470 }
1471
1472 if (strcmp(chainmode, "ecb") && !ivmode) {
1473 ti->error = "IV mechanism required";
1474 return -EINVAL;
1475 }
1476
1477 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
1478 if (!cipher_api)
1479 goto bad_mem;
1480
1481 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
1482 "%s(%s)", chainmode, cipher);
1483 if (ret < 0) {
1484 kfree(cipher_api);
1485 goto bad_mem;
1486 }
1487
1488 /* Allocate cipher */
1489 for_each_possible_cpu(cpu) {
1490 ret = crypt_alloc_tfms(cc, cpu, cipher_api);
1491 if (ret < 0) {
1492 ti->error = "Error allocating crypto tfm";
1493 goto bad;
1494 }
1495 }
1496
1497 /* Initialize and set key */
1498 ret = crypt_set_key(cc, key);
1499 if (ret < 0) {
1500 ti->error = "Error decoding and setting key";
1501 goto bad;
1502 }
1503
1504 /* Initialize IV */
1505 cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
1506 if (cc->iv_size)
1507 /* at least a 64 bit sector number should fit in our buffer */
1508 cc->iv_size = max(cc->iv_size,
1509 (unsigned int)(sizeof(u64) / sizeof(u8)));
1510 else if (ivmode) {
1511 DMWARN("Selected cipher does not support IVs");
1512 ivmode = NULL;
1513 }
1514
1515 /* Choose ivmode, see comments at iv code. */
1516 if (ivmode == NULL)
1517 cc->iv_gen_ops = NULL;
1518 else if (strcmp(ivmode, "plain") == 0)
1519 cc->iv_gen_ops = &crypt_iv_plain_ops;
1520 else if (strcmp(ivmode, "plain64") == 0)
1521 cc->iv_gen_ops = &crypt_iv_plain64_ops;
1522 else if (strcmp(ivmode, "essiv") == 0)
1523 cc->iv_gen_ops = &crypt_iv_essiv_ops;
1524 else if (strcmp(ivmode, "benbi") == 0)
1525 cc->iv_gen_ops = &crypt_iv_benbi_ops;
1526 else if (strcmp(ivmode, "null") == 0)
1527 cc->iv_gen_ops = &crypt_iv_null_ops;
1528 else if (strcmp(ivmode, "lmk") == 0) {
1529 cc->iv_gen_ops = &crypt_iv_lmk_ops;
1530 /* Version 2 and 3 is recognised according
1531 * to length of provided multi-key string.
1532 * If present (version 3), last key is used as IV seed.
1533 */
1534 if (cc->key_size % cc->key_parts)
1535 cc->key_parts++;
1536 } else {
1537 ret = -EINVAL;
1538 ti->error = "Invalid IV mode";
1539 goto bad;
1540 }
1541
1542 /* Allocate IV */
1543 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
1544 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
1545 if (ret < 0) {
1546 ti->error = "Error creating IV";
1547 goto bad;
1548 }
1549 }
1550
1551 /* Initialize IV (set keys for ESSIV etc) */
1552 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
1553 ret = cc->iv_gen_ops->init(cc);
1554 if (ret < 0) {
1555 ti->error = "Error initialising IV";
1556 goto bad;
1557 }
1558 }
1559
1560 ret = 0;
1561bad:
1562 kfree(cipher_api);
1563 return ret;
1564
1565bad_mem:
1566 ti->error = "Cannot allocate cipher strings";
1567 return -ENOMEM;
1568}
1569
1570/*
1571 * Construct an encryption mapping:
1572 * <cipher> <key> <iv_offset> <dev_path> <start>
1573 */
1574static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
1575{
1576 struct crypt_config *cc;
1577 unsigned int key_size, opt_params;
1578 unsigned long long tmpll;
1579 int ret;
1580 struct dm_arg_set as;
1581 const char *opt_string;
1582
1583 static struct dm_arg _args[] = {
1584 {0, 1, "Invalid number of feature args"},
1585 };
1586
1587 if (argc < 5) {
1588 ti->error = "Not enough arguments";
1589 return -EINVAL;
1590 }
1591
1592 key_size = strlen(argv[1]) >> 1;
1593
1594 cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);
1595 if (!cc) {
1596 ti->error = "Cannot allocate encryption context";
1597 return -ENOMEM;
1598 }
1599 cc->key_size = key_size;
1600
1601 ti->private = cc;
1602 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
1603 if (ret < 0)
1604 goto bad;
1605
1606 ret = -ENOMEM;
1607 cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool);
1608 if (!cc->io_pool) {
1609 ti->error = "Cannot allocate crypt io mempool";
1610 goto bad;
1611 }
1612
1613 cc->dmreq_start = sizeof(struct ablkcipher_request);
1614 cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
1615 cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
1616 cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) &
1617 ~(crypto_tfm_ctx_alignment() - 1);
1618
1619 cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
1620 sizeof(struct dm_crypt_request) + cc->iv_size);
1621 if (!cc->req_pool) {
1622 ti->error = "Cannot allocate crypt request mempool";
1623 goto bad;
1624 }
1625
1626 cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
1627 if (!cc->page_pool) {
1628 ti->error = "Cannot allocate page mempool";
1629 goto bad;
1630 }
1631
1632 cc->bs = bioset_create(MIN_IOS, 0);
1633 if (!cc->bs) {
1634 ti->error = "Cannot allocate crypt bioset";
1635 goto bad;
1636 }
1637
1638 ret = -EINVAL;
1639 if (sscanf(argv[2], "%llu", &tmpll) != 1) {
1640 ti->error = "Invalid iv_offset sector";
1641 goto bad;
1642 }
1643 cc->iv_offset = tmpll;
1644
1645 if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) {
1646 ti->error = "Device lookup failed";
1647 goto bad;
1648 }
1649
1650 if (sscanf(argv[4], "%llu", &tmpll) != 1) {
1651 ti->error = "Invalid device sector";
1652 goto bad;
1653 }
1654 cc->start = tmpll;
1655
1656 argv += 5;
1657 argc -= 5;
1658
1659 /* Optional parameters */
1660 if (argc) {
1661 as.argc = argc;
1662 as.argv = argv;
1663
1664 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
1665 if (ret)
1666 goto bad;
1667
1668 opt_string = dm_shift_arg(&as);
1669
1670 if (opt_params == 1 && opt_string &&
1671 !strcasecmp(opt_string, "allow_discards"))
1672 ti->num_discard_requests = 1;
1673 else if (opt_params) {
1674 ret = -EINVAL;
1675 ti->error = "Invalid feature arguments";
1676 goto bad;
1677 }
1678 }
1679
1680 ret = -ENOMEM;
1681 cc->io_queue = alloc_workqueue("kcryptd_io",
1682 WQ_NON_REENTRANT|
1683 WQ_MEM_RECLAIM,
1684 1);
1685 if (!cc->io_queue) {
1686 ti->error = "Couldn't create kcryptd io queue";
1687 goto bad;
1688 }
1689
1690 cc->crypt_queue = alloc_workqueue("kcryptd",
1691 WQ_NON_REENTRANT|
1692 WQ_CPU_INTENSIVE|
1693 WQ_MEM_RECLAIM,
1694 1);
1695 if (!cc->crypt_queue) {
1696 ti->error = "Couldn't create kcryptd queue";
1697 goto bad;
1698 }
1699
1700 ti->num_flush_requests = 1;
1701 ti->discard_zeroes_data_unsupported = 1;
1702
1703 return 0;
1704
1705bad:
1706 crypt_dtr(ti);
1707 return ret;
1708}
1709
1710static int crypt_map(struct dm_target *ti, struct bio *bio,
1711 union map_info *map_context)
1712{
1713 struct dm_crypt_io *io;
1714 struct crypt_config *cc;
1715
1716 /*
1717 * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
1718 * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight
1719 * - for REQ_DISCARD caller must use flush if IO ordering matters
1720 */
1721 if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
1722 cc = ti->private;
1723 bio->bi_bdev = cc->dev->bdev;
1724 if (bio_sectors(bio))
1725 bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector);
1726 return DM_MAPIO_REMAPPED;
1727 }
1728
1729 io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector));
1730
1731 if (bio_data_dir(io->base_bio) == READ) {
1732 if (kcryptd_io_read(io, GFP_NOWAIT))
1733 kcryptd_queue_io(io);
1734 } else
1735 kcryptd_queue_crypt(io);
1736
1737 return DM_MAPIO_SUBMITTED;
1738}
1739
1740static int crypt_status(struct dm_target *ti, status_type_t type,
1741 char *result, unsigned int maxlen)
1742{
1743 struct crypt_config *cc = ti->private;
1744 unsigned int sz = 0;
1745
1746 switch (type) {
1747 case STATUSTYPE_INFO:
1748 result[0] = '\0';
1749 break;
1750
1751 case STATUSTYPE_TABLE:
1752 DMEMIT("%s ", cc->cipher_string);
1753
1754 if (cc->key_size > 0) {
1755 if ((maxlen - sz) < ((cc->key_size << 1) + 1))
1756 return -ENOMEM;
1757
1758 crypt_encode_key(result + sz, cc->key, cc->key_size);
1759 sz += cc->key_size << 1;
1760 } else {
1761 if (sz >= maxlen)
1762 return -ENOMEM;
1763 result[sz++] = '-';
1764 }
1765
1766 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
1767 cc->dev->name, (unsigned long long)cc->start);
1768
1769 if (ti->num_discard_requests)
1770 DMEMIT(" 1 allow_discards");
1771
1772 break;
1773 }
1774 return 0;
1775}
1776
1777static void crypt_postsuspend(struct dm_target *ti)
1778{
1779 struct crypt_config *cc = ti->private;
1780
1781 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1782}
1783
1784static int crypt_preresume(struct dm_target *ti)
1785{
1786 struct crypt_config *cc = ti->private;
1787
1788 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
1789 DMERR("aborting resume - crypt key is not set.");
1790 return -EAGAIN;
1791 }
1792
1793 return 0;
1794}
1795
1796static void crypt_resume(struct dm_target *ti)
1797{
1798 struct crypt_config *cc = ti->private;
1799
1800 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1801}
1802
1803/* Message interface
1804 * key set <key>
1805 * key wipe
1806 */
1807static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
1808{
1809 struct crypt_config *cc = ti->private;
1810 int ret = -EINVAL;
1811
1812 if (argc < 2)
1813 goto error;
1814
1815 if (!strcasecmp(argv[0], "key")) {
1816 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
1817 DMWARN("not suspended during key manipulation.");
1818 return -EINVAL;
1819 }
1820 if (argc == 3 && !strcasecmp(argv[1], "set")) {
1821 ret = crypt_set_key(cc, argv[2]);
1822 if (ret)
1823 return ret;
1824 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
1825 ret = cc->iv_gen_ops->init(cc);
1826 return ret;
1827 }
1828 if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
1829 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
1830 ret = cc->iv_gen_ops->wipe(cc);
1831 if (ret)
1832 return ret;
1833 }
1834 return crypt_wipe_key(cc);
1835 }
1836 }
1837
1838error:
1839 DMWARN("unrecognised message received.");
1840 return -EINVAL;
1841}
1842
1843static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
1844 struct bio_vec *biovec, int max_size)
1845{
1846 struct crypt_config *cc = ti->private;
1847 struct request_queue *q = bdev_get_queue(cc->dev->bdev);
1848
1849 if (!q->merge_bvec_fn)
1850 return max_size;
1851
1852 bvm->bi_bdev = cc->dev->bdev;
1853 bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector);
1854
1855 return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
1856}
1857
1858static int crypt_iterate_devices(struct dm_target *ti,
1859 iterate_devices_callout_fn fn, void *data)
1860{
1861 struct crypt_config *cc = ti->private;
1862
1863 return fn(ti, cc->dev, cc->start, ti->len, data);
1864}
1865
1866static struct target_type crypt_target = {
1867 .name = "crypt",
1868 .version = {1, 11, 0},
1869 .module = THIS_MODULE,
1870 .ctr = crypt_ctr,
1871 .dtr = crypt_dtr,
1872 .map = crypt_map,
1873 .status = crypt_status,
1874 .postsuspend = crypt_postsuspend,
1875 .preresume = crypt_preresume,
1876 .resume = crypt_resume,
1877 .message = crypt_message,
1878 .merge = crypt_merge,
1879 .iterate_devices = crypt_iterate_devices,
1880};
1881
1882static int __init dm_crypt_init(void)
1883{
1884 int r;
1885
1886 _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0);
1887 if (!_crypt_io_pool)
1888 return -ENOMEM;
1889
1890 r = dm_register_target(&crypt_target);
1891 if (r < 0) {
1892 DMERR("register failed %d", r);
1893 kmem_cache_destroy(_crypt_io_pool);
1894 }
1895
1896 return r;
1897}
1898
1899static void __exit dm_crypt_exit(void)
1900{
1901 dm_unregister_target(&crypt_target);
1902 kmem_cache_destroy(_crypt_io_pool);
1903}
1904
1905module_init(dm_crypt_init);
1906module_exit(dm_crypt_exit);
1907
1908MODULE_AUTHOR("Christophe Saout <christophe@saout.de>");
1909MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
1910MODULE_LICENSE("GPL");