block: make /sys/block/<dev>/queue/discard_max_bytes writeable
[linux-2.6-block.git] / drivers / md / dm-crypt.c
CommitLineData
1da177e4 1/*
bf14299f 2 * Copyright (C) 2003 Jana Saout <jana@saout.de>
1da177e4 3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
54cea3f6 4 * Copyright (C) 2006-2015 Red Hat, Inc. All rights reserved.
ed04d981 5 * Copyright (C) 2013 Milan Broz <gmazyland@gmail.com>
1da177e4
LT
6 *
7 * This file is released under the GPL.
8 */
9
43d69034 10#include <linux/completion.h>
d1806f6a 11#include <linux/err.h>
1da177e4
LT
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/kernel.h>
15#include <linux/bio.h>
16#include <linux/blkdev.h>
17#include <linux/mempool.h>
18#include <linux/slab.h>
19#include <linux/crypto.h>
20#include <linux/workqueue.h>
dc267621 21#include <linux/kthread.h>
3fcfab16 22#include <linux/backing-dev.h>
60063497 23#include <linux/atomic.h>
378f058c 24#include <linux/scatterlist.h>
b3c5fd30 25#include <linux/rbtree.h>
1da177e4 26#include <asm/page.h>
48527fa7 27#include <asm/unaligned.h>
34745785
MB
28#include <crypto/hash.h>
29#include <crypto/md5.h>
30#include <crypto/algapi.h>
1da177e4 31
586e80e6 32#include <linux/device-mapper.h>
1da177e4 33
72d94861 34#define DM_MSG_PREFIX "crypt"
1da177e4 35
1da177e4
LT
36/*
37 * context holding the current state of a multi-part conversion
38 */
39struct convert_context {
43d69034 40 struct completion restart;
1da177e4
LT
41 struct bio *bio_in;
42 struct bio *bio_out;
003b5c57
KO
43 struct bvec_iter iter_in;
44 struct bvec_iter iter_out;
c66029f4 45 sector_t cc_sector;
40b6229b 46 atomic_t cc_pending;
610f2de3 47 struct ablkcipher_request *req;
1da177e4
LT
48};
49
53017030
MB
50/*
51 * per bio private data
52 */
53struct dm_crypt_io {
49a8a920 54 struct crypt_config *cc;
53017030
MB
55 struct bio *base_bio;
56 struct work_struct work;
57
58 struct convert_context ctx;
59
40b6229b 60 atomic_t io_pending;
53017030 61 int error;
0c395b0f 62 sector_t sector;
dc267621 63
b3c5fd30 64 struct rb_node rb_node;
298a9fa0 65} CRYPTO_MINALIGN_ATTR;
53017030 66
01482b76 67struct dm_crypt_request {
b2174eeb 68 struct convert_context *ctx;
01482b76
MB
69 struct scatterlist sg_in;
70 struct scatterlist sg_out;
2dc5327d 71 sector_t iv_sector;
01482b76
MB
72};
73
1da177e4
LT
74struct crypt_config;
75
76struct crypt_iv_operations {
77 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
d469f841 78 const char *opts);
1da177e4 79 void (*dtr)(struct crypt_config *cc);
b95bf2d3 80 int (*init)(struct crypt_config *cc);
542da317 81 int (*wipe)(struct crypt_config *cc);
2dc5327d
MB
82 int (*generator)(struct crypt_config *cc, u8 *iv,
83 struct dm_crypt_request *dmreq);
84 int (*post)(struct crypt_config *cc, u8 *iv,
85 struct dm_crypt_request *dmreq);
1da177e4
LT
86};
87
60473592 88struct iv_essiv_private {
b95bf2d3
MB
89 struct crypto_hash *hash_tfm;
90 u8 *salt;
60473592
MB
91};
92
93struct iv_benbi_private {
94 int shift;
95};
96
34745785
MB
97#define LMK_SEED_SIZE 64 /* hash + 0 */
98struct iv_lmk_private {
99 struct crypto_shash *hash_tfm;
100 u8 *seed;
101};
102
ed04d981
MB
103#define TCW_WHITENING_SIZE 16
104struct iv_tcw_private {
105 struct crypto_shash *crc32_tfm;
106 u8 *iv_seed;
107 u8 *whitening;
108};
109
1da177e4
LT
110/*
111 * Crypt: maps a linear range of a block device
112 * and encrypts / decrypts at the same time.
113 */
0f5d8e6e
MP
114enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
115 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD };
c0297721
AK
116
117/*
610f2de3 118 * The fields in here must be read only after initialization.
c0297721 119 */
1da177e4
LT
120struct crypt_config {
121 struct dm_dev *dev;
122 sector_t start;
123
124 /*
ddd42edf
MB
125 * pool for per bio private data, crypto requests and
126 * encryption requeusts/buffer pages
1da177e4 127 */
ddd42edf 128 mempool_t *req_pool;
1da177e4 129 mempool_t *page_pool;
6a24c718 130 struct bio_set *bs;
7145c241 131 struct mutex bio_alloc_lock;
1da177e4 132
cabf08e4
MB
133 struct workqueue_struct *io_queue;
134 struct workqueue_struct *crypt_queue;
3f1e9070 135
dc267621
MP
136 struct task_struct *write_thread;
137 wait_queue_head_t write_thread_wait;
b3c5fd30 138 struct rb_root write_tree;
dc267621 139
5ebaee6d 140 char *cipher;
7dbcd137 141 char *cipher_string;
5ebaee6d 142
1da177e4 143 struct crypt_iv_operations *iv_gen_ops;
79066ad3 144 union {
60473592
MB
145 struct iv_essiv_private essiv;
146 struct iv_benbi_private benbi;
34745785 147 struct iv_lmk_private lmk;
ed04d981 148 struct iv_tcw_private tcw;
79066ad3 149 } iv_gen_private;
1da177e4
LT
150 sector_t iv_offset;
151 unsigned int iv_size;
152
fd2d231f
MP
153 /* ESSIV: struct crypto_cipher *essiv_tfm */
154 void *iv_private;
155 struct crypto_ablkcipher **tfms;
d1f96423 156 unsigned tfms_count;
c0297721 157
ddd42edf
MB
158 /*
159 * Layout of each crypto request:
160 *
161 * struct ablkcipher_request
162 * context
163 * padding
164 * struct dm_crypt_request
165 * padding
166 * IV
167 *
168 * The padding is added so that dm_crypt_request and the IV are
169 * correctly aligned.
170 */
171 unsigned int dmreq_start;
ddd42edf 172
298a9fa0
MP
173 unsigned int per_bio_data_size;
174
e48d4bbf 175 unsigned long flags;
1da177e4 176 unsigned int key_size;
da31a078
MB
177 unsigned int key_parts; /* independent parts in key buffer */
178 unsigned int key_extra_size; /* additional keys length */
1da177e4
LT
179 u8 key[0];
180};
181
6a24c718 182#define MIN_IOS 16
1da177e4 183
028867ac 184static void clone_init(struct dm_crypt_io *, struct bio *);
395b167c 185static void kcryptd_queue_crypt(struct dm_crypt_io *io);
2dc5327d 186static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq);
027581f3 187
c0297721
AK
188/*
189 * Use this to access cipher attributes that are the same for each CPU.
190 */
191static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
192{
fd2d231f 193 return cc->tfms[0];
c0297721
AK
194}
195
1da177e4
LT
196/*
197 * Different IV generation algorithms:
198 *
3c164bd8 199 * plain: the initial vector is the 32-bit little-endian version of the sector
3a4fa0a2 200 * number, padded with zeros if necessary.
1da177e4 201 *
61afef61
MB
202 * plain64: the initial vector is the 64-bit little-endian version of the sector
203 * number, padded with zeros if necessary.
204 *
3c164bd8
RS
205 * essiv: "encrypted sector|salt initial vector", the sector number is
206 * encrypted with the bulk cipher using a salt as key. The salt
207 * should be derived from the bulk cipher's key via hashing.
1da177e4 208 *
48527fa7
RS
209 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
210 * (needed for LRW-32-AES and possible other narrow block modes)
211 *
46b47730
LN
212 * null: the initial vector is always zero. Provides compatibility with
213 * obsolete loop_fish2 devices. Do not use for new devices.
214 *
34745785
MB
215 * lmk: Compatible implementation of the block chaining mode used
216 * by the Loop-AES block device encryption system
217 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
218 * It operates on full 512 byte sectors and uses CBC
219 * with an IV derived from the sector number, the data and
220 * optionally extra IV seed.
221 * This means that after decryption the first block
222 * of sector must be tweaked according to decrypted data.
223 * Loop-AES can use three encryption schemes:
224 * version 1: is plain aes-cbc mode
225 * version 2: uses 64 multikey scheme with lmk IV generator
226 * version 3: the same as version 2 with additional IV seed
227 * (it uses 65 keys, last key is used as IV seed)
228 *
ed04d981
MB
229 * tcw: Compatible implementation of the block chaining mode used
230 * by the TrueCrypt device encryption system (prior to version 4.1).
e44f23b3 231 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
ed04d981
MB
232 * It operates on full 512 byte sectors and uses CBC
233 * with an IV derived from initial key and the sector number.
234 * In addition, whitening value is applied on every sector, whitening
235 * is calculated from initial key, sector number and mixed using CRC32.
236 * Note that this encryption scheme is vulnerable to watermarking attacks
237 * and should be used for old compatible containers access only.
238 *
1da177e4
LT
239 * plumb: unimplemented, see:
240 * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
241 */
242
2dc5327d
MB
243static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
244 struct dm_crypt_request *dmreq)
1da177e4
LT
245{
246 memset(iv, 0, cc->iv_size);
283a8328 247 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
1da177e4
LT
248
249 return 0;
250}
251
61afef61 252static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
2dc5327d 253 struct dm_crypt_request *dmreq)
61afef61
MB
254{
255 memset(iv, 0, cc->iv_size);
283a8328 256 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
61afef61
MB
257
258 return 0;
259}
260
b95bf2d3
MB
261/* Initialise ESSIV - compute salt but no local memory allocations */
262static int crypt_iv_essiv_init(struct crypt_config *cc)
263{
264 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
265 struct hash_desc desc;
266 struct scatterlist sg;
c0297721 267 struct crypto_cipher *essiv_tfm;
fd2d231f 268 int err;
b95bf2d3
MB
269
270 sg_init_one(&sg, cc->key, cc->key_size);
271 desc.tfm = essiv->hash_tfm;
272 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
273
274 err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt);
275 if (err)
276 return err;
277
fd2d231f 278 essiv_tfm = cc->iv_private;
c0297721 279
fd2d231f
MP
280 err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
281 crypto_hash_digestsize(essiv->hash_tfm));
282 if (err)
283 return err;
c0297721
AK
284
285 return 0;
b95bf2d3
MB
286}
287
542da317
MB
288/* Wipe salt and reset key derived from volume key */
289static int crypt_iv_essiv_wipe(struct crypt_config *cc)
290{
291 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
292 unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
c0297721 293 struct crypto_cipher *essiv_tfm;
fd2d231f 294 int r, err = 0;
542da317
MB
295
296 memset(essiv->salt, 0, salt_size);
297
fd2d231f
MP
298 essiv_tfm = cc->iv_private;
299 r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
300 if (r)
301 err = r;
c0297721
AK
302
303 return err;
304}
305
306/* Set up per cpu cipher state */
307static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
308 struct dm_target *ti,
309 u8 *salt, unsigned saltsize)
310{
311 struct crypto_cipher *essiv_tfm;
312 int err;
313
314 /* Setup the essiv_tfm with the given salt */
315 essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
316 if (IS_ERR(essiv_tfm)) {
317 ti->error = "Error allocating crypto tfm for ESSIV";
318 return essiv_tfm;
319 }
320
321 if (crypto_cipher_blocksize(essiv_tfm) !=
322 crypto_ablkcipher_ivsize(any_tfm(cc))) {
323 ti->error = "Block size of ESSIV cipher does "
324 "not match IV size of block cipher";
325 crypto_free_cipher(essiv_tfm);
326 return ERR_PTR(-EINVAL);
327 }
328
329 err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
330 if (err) {
331 ti->error = "Failed to set key for ESSIV cipher";
332 crypto_free_cipher(essiv_tfm);
333 return ERR_PTR(err);
334 }
335
336 return essiv_tfm;
542da317
MB
337}
338
60473592
MB
339static void crypt_iv_essiv_dtr(struct crypt_config *cc)
340{
c0297721 341 struct crypto_cipher *essiv_tfm;
60473592
MB
342 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
343
b95bf2d3
MB
344 crypto_free_hash(essiv->hash_tfm);
345 essiv->hash_tfm = NULL;
346
347 kzfree(essiv->salt);
348 essiv->salt = NULL;
c0297721 349
fd2d231f 350 essiv_tfm = cc->iv_private;
c0297721 351
fd2d231f
MP
352 if (essiv_tfm)
353 crypto_free_cipher(essiv_tfm);
c0297721 354
fd2d231f 355 cc->iv_private = NULL;
60473592
MB
356}
357
1da177e4 358static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
d469f841 359 const char *opts)
1da177e4 360{
5861f1be
MB
361 struct crypto_cipher *essiv_tfm = NULL;
362 struct crypto_hash *hash_tfm = NULL;
5861f1be 363 u8 *salt = NULL;
fd2d231f 364 int err;
1da177e4 365
5861f1be 366 if (!opts) {
72d94861 367 ti->error = "Digest algorithm missing for ESSIV mode";
1da177e4
LT
368 return -EINVAL;
369 }
370
b95bf2d3 371 /* Allocate hash algorithm */
35058687
HX
372 hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC);
373 if (IS_ERR(hash_tfm)) {
72d94861 374 ti->error = "Error initializing ESSIV hash";
5861f1be
MB
375 err = PTR_ERR(hash_tfm);
376 goto bad;
1da177e4
LT
377 }
378
b95bf2d3 379 salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL);
5861f1be 380 if (!salt) {
72d94861 381 ti->error = "Error kmallocing salt storage in ESSIV";
5861f1be
MB
382 err = -ENOMEM;
383 goto bad;
1da177e4
LT
384 }
385
b95bf2d3 386 cc->iv_gen_private.essiv.salt = salt;
b95bf2d3
MB
387 cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
388
fd2d231f
MP
389 essiv_tfm = setup_essiv_cpu(cc, ti, salt,
390 crypto_hash_digestsize(hash_tfm));
391 if (IS_ERR(essiv_tfm)) {
392 crypt_iv_essiv_dtr(cc);
393 return PTR_ERR(essiv_tfm);
c0297721 394 }
fd2d231f 395 cc->iv_private = essiv_tfm;
c0297721 396
1da177e4 397 return 0;
5861f1be
MB
398
399bad:
5861f1be
MB
400 if (hash_tfm && !IS_ERR(hash_tfm))
401 crypto_free_hash(hash_tfm);
b95bf2d3 402 kfree(salt);
5861f1be 403 return err;
1da177e4
LT
404}
405
2dc5327d
MB
406static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
407 struct dm_crypt_request *dmreq)
1da177e4 408{
fd2d231f 409 struct crypto_cipher *essiv_tfm = cc->iv_private;
c0297721 410
1da177e4 411 memset(iv, 0, cc->iv_size);
283a8328 412 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
c0297721
AK
413 crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
414
1da177e4
LT
415 return 0;
416}
417
48527fa7
RS
418static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
419 const char *opts)
420{
c0297721 421 unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
f0d1b0b3 422 int log = ilog2(bs);
48527fa7
RS
423
424 /* we need to calculate how far we must shift the sector count
425 * to get the cipher block count, we use this shift in _gen */
426
427 if (1 << log != bs) {
428 ti->error = "cypher blocksize is not a power of 2";
429 return -EINVAL;
430 }
431
432 if (log > 9) {
433 ti->error = "cypher blocksize is > 512";
434 return -EINVAL;
435 }
436
60473592 437 cc->iv_gen_private.benbi.shift = 9 - log;
48527fa7
RS
438
439 return 0;
440}
441
442static void crypt_iv_benbi_dtr(struct crypt_config *cc)
443{
48527fa7
RS
444}
445
2dc5327d
MB
446static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
447 struct dm_crypt_request *dmreq)
48527fa7 448{
79066ad3
HX
449 __be64 val;
450
48527fa7 451 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
79066ad3 452
2dc5327d 453 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
79066ad3 454 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
48527fa7 455
1da177e4
LT
456 return 0;
457}
458
2dc5327d
MB
459static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
460 struct dm_crypt_request *dmreq)
46b47730
LN
461{
462 memset(iv, 0, cc->iv_size);
463
464 return 0;
465}
466
34745785
MB
467static void crypt_iv_lmk_dtr(struct crypt_config *cc)
468{
469 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
470
471 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
472 crypto_free_shash(lmk->hash_tfm);
473 lmk->hash_tfm = NULL;
474
475 kzfree(lmk->seed);
476 lmk->seed = NULL;
477}
478
479static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
480 const char *opts)
481{
482 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
483
484 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
485 if (IS_ERR(lmk->hash_tfm)) {
486 ti->error = "Error initializing LMK hash";
487 return PTR_ERR(lmk->hash_tfm);
488 }
489
490 /* No seed in LMK version 2 */
491 if (cc->key_parts == cc->tfms_count) {
492 lmk->seed = NULL;
493 return 0;
494 }
495
496 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
497 if (!lmk->seed) {
498 crypt_iv_lmk_dtr(cc);
499 ti->error = "Error kmallocing seed storage in LMK";
500 return -ENOMEM;
501 }
502
503 return 0;
504}
505
506static int crypt_iv_lmk_init(struct crypt_config *cc)
507{
508 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
509 int subkey_size = cc->key_size / cc->key_parts;
510
511 /* LMK seed is on the position of LMK_KEYS + 1 key */
512 if (lmk->seed)
513 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
514 crypto_shash_digestsize(lmk->hash_tfm));
515
516 return 0;
517}
518
519static int crypt_iv_lmk_wipe(struct crypt_config *cc)
520{
521 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
522
523 if (lmk->seed)
524 memset(lmk->seed, 0, LMK_SEED_SIZE);
525
526 return 0;
527}
528
529static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
530 struct dm_crypt_request *dmreq,
531 u8 *data)
532{
533 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
b6106265 534 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
34745785 535 struct md5_state md5state;
da31a078 536 __le32 buf[4];
34745785
MB
537 int i, r;
538
b6106265
JSM
539 desc->tfm = lmk->hash_tfm;
540 desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
34745785 541
b6106265 542 r = crypto_shash_init(desc);
34745785
MB
543 if (r)
544 return r;
545
546 if (lmk->seed) {
b6106265 547 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
34745785
MB
548 if (r)
549 return r;
550 }
551
552 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
b6106265 553 r = crypto_shash_update(desc, data + 16, 16 * 31);
34745785
MB
554 if (r)
555 return r;
556
557 /* Sector is cropped to 56 bits here */
558 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
559 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
560 buf[2] = cpu_to_le32(4024);
561 buf[3] = 0;
b6106265 562 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
34745785
MB
563 if (r)
564 return r;
565
566 /* No MD5 padding here */
b6106265 567 r = crypto_shash_export(desc, &md5state);
34745785
MB
568 if (r)
569 return r;
570
571 for (i = 0; i < MD5_HASH_WORDS; i++)
572 __cpu_to_le32s(&md5state.hash[i]);
573 memcpy(iv, &md5state.hash, cc->iv_size);
574
575 return 0;
576}
577
578static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
579 struct dm_crypt_request *dmreq)
580{
581 u8 *src;
582 int r = 0;
583
584 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
c2e022cb 585 src = kmap_atomic(sg_page(&dmreq->sg_in));
34745785 586 r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset);
c2e022cb 587 kunmap_atomic(src);
34745785
MB
588 } else
589 memset(iv, 0, cc->iv_size);
590
591 return r;
592}
593
594static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
595 struct dm_crypt_request *dmreq)
596{
597 u8 *dst;
598 int r;
599
600 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
601 return 0;
602
c2e022cb 603 dst = kmap_atomic(sg_page(&dmreq->sg_out));
34745785
MB
604 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + dmreq->sg_out.offset);
605
606 /* Tweak the first block of plaintext sector */
607 if (!r)
608 crypto_xor(dst + dmreq->sg_out.offset, iv, cc->iv_size);
609
c2e022cb 610 kunmap_atomic(dst);
34745785
MB
611 return r;
612}
613
ed04d981
MB
614static void crypt_iv_tcw_dtr(struct crypt_config *cc)
615{
616 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
617
618 kzfree(tcw->iv_seed);
619 tcw->iv_seed = NULL;
620 kzfree(tcw->whitening);
621 tcw->whitening = NULL;
622
623 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
624 crypto_free_shash(tcw->crc32_tfm);
625 tcw->crc32_tfm = NULL;
626}
627
628static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
629 const char *opts)
630{
631 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
632
633 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
634 ti->error = "Wrong key size for TCW";
635 return -EINVAL;
636 }
637
638 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0);
639 if (IS_ERR(tcw->crc32_tfm)) {
640 ti->error = "Error initializing CRC32 in TCW";
641 return PTR_ERR(tcw->crc32_tfm);
642 }
643
644 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
645 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
646 if (!tcw->iv_seed || !tcw->whitening) {
647 crypt_iv_tcw_dtr(cc);
648 ti->error = "Error allocating seed storage in TCW";
649 return -ENOMEM;
650 }
651
652 return 0;
653}
654
655static int crypt_iv_tcw_init(struct crypt_config *cc)
656{
657 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
658 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
659
660 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
661 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
662 TCW_WHITENING_SIZE);
663
664 return 0;
665}
666
667static int crypt_iv_tcw_wipe(struct crypt_config *cc)
668{
669 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
670
671 memset(tcw->iv_seed, 0, cc->iv_size);
672 memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
673
674 return 0;
675}
676
677static int crypt_iv_tcw_whitening(struct crypt_config *cc,
678 struct dm_crypt_request *dmreq,
679 u8 *data)
680{
681 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
682 u64 sector = cpu_to_le64((u64)dmreq->iv_sector);
683 u8 buf[TCW_WHITENING_SIZE];
b6106265 684 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
ed04d981
MB
685 int i, r;
686
687 /* xor whitening with sector number */
688 memcpy(buf, tcw->whitening, TCW_WHITENING_SIZE);
689 crypto_xor(buf, (u8 *)&sector, 8);
690 crypto_xor(&buf[8], (u8 *)&sector, 8);
691
692 /* calculate crc32 for every 32bit part and xor it */
b6106265
JSM
693 desc->tfm = tcw->crc32_tfm;
694 desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
ed04d981 695 for (i = 0; i < 4; i++) {
b6106265 696 r = crypto_shash_init(desc);
ed04d981
MB
697 if (r)
698 goto out;
b6106265 699 r = crypto_shash_update(desc, &buf[i * 4], 4);
ed04d981
MB
700 if (r)
701 goto out;
b6106265 702 r = crypto_shash_final(desc, &buf[i * 4]);
ed04d981
MB
703 if (r)
704 goto out;
705 }
706 crypto_xor(&buf[0], &buf[12], 4);
707 crypto_xor(&buf[4], &buf[8], 4);
708
709 /* apply whitening (8 bytes) to whole sector */
710 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
711 crypto_xor(data + i * 8, buf, 8);
712out:
1a71d6ff 713 memzero_explicit(buf, sizeof(buf));
ed04d981
MB
714 return r;
715}
716
717static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
718 struct dm_crypt_request *dmreq)
719{
720 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
721 u64 sector = cpu_to_le64((u64)dmreq->iv_sector);
722 u8 *src;
723 int r = 0;
724
725 /* Remove whitening from ciphertext */
726 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
727 src = kmap_atomic(sg_page(&dmreq->sg_in));
728 r = crypt_iv_tcw_whitening(cc, dmreq, src + dmreq->sg_in.offset);
729 kunmap_atomic(src);
730 }
731
732 /* Calculate IV */
733 memcpy(iv, tcw->iv_seed, cc->iv_size);
734 crypto_xor(iv, (u8 *)&sector, 8);
735 if (cc->iv_size > 8)
736 crypto_xor(&iv[8], (u8 *)&sector, cc->iv_size - 8);
737
738 return r;
739}
740
741static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
742 struct dm_crypt_request *dmreq)
743{
744 u8 *dst;
745 int r;
746
747 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
748 return 0;
749
750 /* Apply whitening on ciphertext */
751 dst = kmap_atomic(sg_page(&dmreq->sg_out));
752 r = crypt_iv_tcw_whitening(cc, dmreq, dst + dmreq->sg_out.offset);
753 kunmap_atomic(dst);
754
755 return r;
756}
757
1da177e4
LT
758static struct crypt_iv_operations crypt_iv_plain_ops = {
759 .generator = crypt_iv_plain_gen
760};
761
61afef61
MB
762static struct crypt_iv_operations crypt_iv_plain64_ops = {
763 .generator = crypt_iv_plain64_gen
764};
765
1da177e4
LT
766static struct crypt_iv_operations crypt_iv_essiv_ops = {
767 .ctr = crypt_iv_essiv_ctr,
768 .dtr = crypt_iv_essiv_dtr,
b95bf2d3 769 .init = crypt_iv_essiv_init,
542da317 770 .wipe = crypt_iv_essiv_wipe,
1da177e4
LT
771 .generator = crypt_iv_essiv_gen
772};
773
48527fa7
RS
774static struct crypt_iv_operations crypt_iv_benbi_ops = {
775 .ctr = crypt_iv_benbi_ctr,
776 .dtr = crypt_iv_benbi_dtr,
777 .generator = crypt_iv_benbi_gen
778};
1da177e4 779
46b47730
LN
780static struct crypt_iv_operations crypt_iv_null_ops = {
781 .generator = crypt_iv_null_gen
782};
783
34745785
MB
784static struct crypt_iv_operations crypt_iv_lmk_ops = {
785 .ctr = crypt_iv_lmk_ctr,
786 .dtr = crypt_iv_lmk_dtr,
787 .init = crypt_iv_lmk_init,
788 .wipe = crypt_iv_lmk_wipe,
789 .generator = crypt_iv_lmk_gen,
790 .post = crypt_iv_lmk_post
791};
792
ed04d981
MB
793static struct crypt_iv_operations crypt_iv_tcw_ops = {
794 .ctr = crypt_iv_tcw_ctr,
795 .dtr = crypt_iv_tcw_dtr,
796 .init = crypt_iv_tcw_init,
797 .wipe = crypt_iv_tcw_wipe,
798 .generator = crypt_iv_tcw_gen,
799 .post = crypt_iv_tcw_post
800};
801
d469f841
MB
802static void crypt_convert_init(struct crypt_config *cc,
803 struct convert_context *ctx,
804 struct bio *bio_out, struct bio *bio_in,
fcd369da 805 sector_t sector)
1da177e4
LT
806{
807 ctx->bio_in = bio_in;
808 ctx->bio_out = bio_out;
003b5c57
KO
809 if (bio_in)
810 ctx->iter_in = bio_in->bi_iter;
811 if (bio_out)
812 ctx->iter_out = bio_out->bi_iter;
c66029f4 813 ctx->cc_sector = sector + cc->iv_offset;
43d69034 814 init_completion(&ctx->restart);
1da177e4
LT
815}
816
b2174eeb
HY
817static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
818 struct ablkcipher_request *req)
819{
820 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
821}
822
823static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
824 struct dm_crypt_request *dmreq)
825{
826 return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
827}
828
2dc5327d
MB
829static u8 *iv_of_dmreq(struct crypt_config *cc,
830 struct dm_crypt_request *dmreq)
831{
832 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
833 crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
834}
835
01482b76 836static int crypt_convert_block(struct crypt_config *cc,
3a7f6c99
MB
837 struct convert_context *ctx,
838 struct ablkcipher_request *req)
01482b76 839{
003b5c57
KO
840 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
841 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
3a7f6c99
MB
842 struct dm_crypt_request *dmreq;
843 u8 *iv;
40b6229b 844 int r;
3a7f6c99 845
b2174eeb 846 dmreq = dmreq_of_req(cc, req);
2dc5327d 847 iv = iv_of_dmreq(cc, dmreq);
01482b76 848
c66029f4 849 dmreq->iv_sector = ctx->cc_sector;
b2174eeb 850 dmreq->ctx = ctx;
3a7f6c99 851 sg_init_table(&dmreq->sg_in, 1);
003b5c57
KO
852 sg_set_page(&dmreq->sg_in, bv_in.bv_page, 1 << SECTOR_SHIFT,
853 bv_in.bv_offset);
01482b76 854
3a7f6c99 855 sg_init_table(&dmreq->sg_out, 1);
003b5c57
KO
856 sg_set_page(&dmreq->sg_out, bv_out.bv_page, 1 << SECTOR_SHIFT,
857 bv_out.bv_offset);
01482b76 858
003b5c57
KO
859 bio_advance_iter(ctx->bio_in, &ctx->iter_in, 1 << SECTOR_SHIFT);
860 bio_advance_iter(ctx->bio_out, &ctx->iter_out, 1 << SECTOR_SHIFT);
01482b76 861
3a7f6c99 862 if (cc->iv_gen_ops) {
2dc5327d 863 r = cc->iv_gen_ops->generator(cc, iv, dmreq);
3a7f6c99
MB
864 if (r < 0)
865 return r;
866 }
867
868 ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
869 1 << SECTOR_SHIFT, iv);
870
871 if (bio_data_dir(ctx->bio_in) == WRITE)
872 r = crypto_ablkcipher_encrypt(req);
873 else
874 r = crypto_ablkcipher_decrypt(req);
875
2dc5327d
MB
876 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
877 r = cc->iv_gen_ops->post(cc, iv, dmreq);
878
3a7f6c99 879 return r;
01482b76
MB
880}
881
95497a96
MB
882static void kcryptd_async_done(struct crypto_async_request *async_req,
883 int error);
c0297721 884
ddd42edf
MB
885static void crypt_alloc_req(struct crypt_config *cc,
886 struct convert_context *ctx)
887{
c66029f4 888 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
c0297721 889
610f2de3
MP
890 if (!ctx->req)
891 ctx->req = mempool_alloc(cc->req_pool, GFP_NOIO);
c0297721 892
610f2de3 893 ablkcipher_request_set_tfm(ctx->req, cc->tfms[key_index]);
54cea3f6
MB
894
895 /*
896 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
897 * requests if driver request queue is full.
898 */
610f2de3 899 ablkcipher_request_set_callback(ctx->req,
c0297721 900 CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
610f2de3 901 kcryptd_async_done, dmreq_of_req(cc, ctx->req));
ddd42edf
MB
902}
903
298a9fa0
MP
904static void crypt_free_req(struct crypt_config *cc,
905 struct ablkcipher_request *req, struct bio *base_bio)
906{
907 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
908
909 if ((struct ablkcipher_request *)(io + 1) != req)
910 mempool_free(req, cc->req_pool);
911}
912
1da177e4
LT
913/*
914 * Encrypt / decrypt data from one bio to another one (can be the same one)
915 */
916static int crypt_convert(struct crypt_config *cc,
d469f841 917 struct convert_context *ctx)
1da177e4 918{
3f1e9070 919 int r;
1da177e4 920
40b6229b 921 atomic_set(&ctx->cc_pending, 1);
c8081618 922
003b5c57 923 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1da177e4 924
3a7f6c99
MB
925 crypt_alloc_req(cc, ctx);
926
40b6229b 927 atomic_inc(&ctx->cc_pending);
3f1e9070 928
610f2de3 929 r = crypt_convert_block(cc, ctx, ctx->req);
3a7f6c99
MB
930
931 switch (r) {
54cea3f6
MB
932 /*
933 * The request was queued by a crypto driver
934 * but the driver request queue is full, let's wait.
935 */
3a7f6c99
MB
936 case -EBUSY:
937 wait_for_completion(&ctx->restart);
16735d02 938 reinit_completion(&ctx->restart);
54cea3f6
MB
939 /* fall through */
940 /*
941 * The request is queued and processed asynchronously,
942 * completion function kcryptd_async_done() will be called.
943 */
c0403ec0 944 case -EINPROGRESS:
610f2de3 945 ctx->req = NULL;
c66029f4 946 ctx->cc_sector++;
3f1e9070 947 continue;
54cea3f6
MB
948 /*
949 * The request was already processed (synchronously).
950 */
3a7f6c99 951 case 0:
40b6229b 952 atomic_dec(&ctx->cc_pending);
c66029f4 953 ctx->cc_sector++;
c7f1b204 954 cond_resched();
3a7f6c99 955 continue;
3a7f6c99 956
54cea3f6 957 /* There was an error while processing the request. */
3f1e9070 958 default:
40b6229b 959 atomic_dec(&ctx->cc_pending);
3f1e9070
MB
960 return r;
961 }
1da177e4
LT
962 }
963
3f1e9070 964 return 0;
1da177e4
LT
965}
966
cf2f1abf
MP
967static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
968
1da177e4
LT
969/*
970 * Generate a new unfragmented bio with the given size
971 * This should never violate the device limitations
7145c241
MP
972 *
973 * This function may be called concurrently. If we allocate from the mempool
974 * concurrently, there is a possibility of deadlock. For example, if we have
975 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
976 * the mempool concurrently, it may deadlock in a situation where both processes
977 * have allocated 128 pages and the mempool is exhausted.
978 *
979 * In order to avoid this scenario we allocate the pages under a mutex.
980 *
981 * In order to not degrade performance with excessive locking, we try
982 * non-blocking allocations without a mutex first but on failure we fallback
983 * to blocking allocations with a mutex.
1da177e4 984 */
cf2f1abf 985static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
1da177e4 986{
49a8a920 987 struct crypt_config *cc = io->cc;
8b004457 988 struct bio *clone;
1da177e4 989 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
7145c241
MP
990 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
991 unsigned i, len, remaining_size;
91e10625 992 struct page *page;
cf2f1abf 993 struct bio_vec *bvec;
1da177e4 994
7145c241
MP
995retry:
996 if (unlikely(gfp_mask & __GFP_WAIT))
997 mutex_lock(&cc->bio_alloc_lock);
998
2f9941b6 999 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs);
8b004457 1000 if (!clone)
7145c241 1001 goto return_clone;
1da177e4 1002
027581f3 1003 clone_init(io, clone);
6a24c718 1004
7145c241
MP
1005 remaining_size = size;
1006
f97380bc 1007 for (i = 0; i < nr_iovecs; i++) {
91e10625 1008 page = mempool_alloc(cc->page_pool, gfp_mask);
7145c241
MP
1009 if (!page) {
1010 crypt_free_buffer_pages(cc, clone);
1011 bio_put(clone);
1012 gfp_mask |= __GFP_WAIT;
1013 goto retry;
1014 }
1da177e4 1015
7145c241 1016 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
91e10625 1017
cf2f1abf
MP
1018 bvec = &clone->bi_io_vec[clone->bi_vcnt++];
1019 bvec->bv_page = page;
1020 bvec->bv_len = len;
1021 bvec->bv_offset = 0;
1da177e4 1022
cf2f1abf 1023 clone->bi_iter.bi_size += len;
1da177e4 1024
7145c241 1025 remaining_size -= len;
1da177e4
LT
1026 }
1027
7145c241
MP
1028return_clone:
1029 if (unlikely(gfp_mask & __GFP_WAIT))
1030 mutex_unlock(&cc->bio_alloc_lock);
1031
8b004457 1032 return clone;
1da177e4
LT
1033}
1034
644bd2f0 1035static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1da177e4 1036{
644bd2f0 1037 unsigned int i;
1da177e4
LT
1038 struct bio_vec *bv;
1039
cb34e057 1040 bio_for_each_segment_all(bv, clone, i) {
1da177e4
LT
1041 BUG_ON(!bv->bv_page);
1042 mempool_free(bv->bv_page, cc->page_pool);
1043 bv->bv_page = NULL;
1044 }
1045}
1046
298a9fa0
MP
1047static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1048 struct bio *bio, sector_t sector)
dc440d1e 1049{
49a8a920 1050 io->cc = cc;
dc440d1e
MB
1051 io->base_bio = bio;
1052 io->sector = sector;
1053 io->error = 0;
610f2de3 1054 io->ctx.req = NULL;
40b6229b 1055 atomic_set(&io->io_pending, 0);
dc440d1e
MB
1056}
1057
3e1a8bdd
MB
1058static void crypt_inc_pending(struct dm_crypt_io *io)
1059{
40b6229b 1060 atomic_inc(&io->io_pending);
3e1a8bdd
MB
1061}
1062
1da177e4
LT
1063/*
1064 * One of the bios was finished. Check for completion of
1065 * the whole request and correctly clean up the buffer.
1066 */
5742fd77 1067static void crypt_dec_pending(struct dm_crypt_io *io)
1da177e4 1068{
49a8a920 1069 struct crypt_config *cc = io->cc;
b35f8caa 1070 struct bio *base_bio = io->base_bio;
b35f8caa 1071 int error = io->error;
1da177e4 1072
40b6229b 1073 if (!atomic_dec_and_test(&io->io_pending))
1da177e4
LT
1074 return;
1075
610f2de3 1076 if (io->ctx.req)
298a9fa0 1077 crypt_free_req(cc, io->ctx.req, base_bio);
b35f8caa 1078
cf2f1abf 1079 bio_endio(base_bio, error);
1da177e4
LT
1080}
1081
1082/*
cabf08e4 1083 * kcryptd/kcryptd_io:
1da177e4
LT
1084 *
1085 * Needed because it would be very unwise to do decryption in an
23541d2d 1086 * interrupt context.
cabf08e4
MB
1087 *
1088 * kcryptd performs the actual encryption or decryption.
1089 *
1090 * kcryptd_io performs the IO submission.
1091 *
1092 * They must be separated as otherwise the final stages could be
1093 * starved by new requests which can block in the first stages due
1094 * to memory allocation.
c0297721
AK
1095 *
1096 * The work is done per CPU global for all dm-crypt instances.
1097 * They should not depend on each other and do not block.
1da177e4 1098 */
6712ecf8 1099static void crypt_endio(struct bio *clone, int error)
8b004457 1100{
028867ac 1101 struct dm_crypt_io *io = clone->bi_private;
49a8a920 1102 struct crypt_config *cc = io->cc;
ee7a491e 1103 unsigned rw = bio_data_dir(clone);
8b004457 1104
adfe4770
MB
1105 if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error))
1106 error = -EIO;
1107
8b004457 1108 /*
6712ecf8 1109 * free the processed pages
8b004457 1110 */
ee7a491e 1111 if (rw == WRITE)
644bd2f0 1112 crypt_free_buffer_pages(cc, clone);
8b004457
MB
1113
1114 bio_put(clone);
8b004457 1115
ee7a491e
MB
1116 if (rw == READ && !error) {
1117 kcryptd_queue_crypt(io);
1118 return;
1119 }
5742fd77
MB
1120
1121 if (unlikely(error))
1122 io->error = error;
1123
1124 crypt_dec_pending(io);
8b004457
MB
1125}
1126
028867ac 1127static void clone_init(struct dm_crypt_io *io, struct bio *clone)
8b004457 1128{
49a8a920 1129 struct crypt_config *cc = io->cc;
8b004457
MB
1130
1131 clone->bi_private = io;
1132 clone->bi_end_io = crypt_endio;
1133 clone->bi_bdev = cc->dev->bdev;
1134 clone->bi_rw = io->base_bio->bi_rw;
1135}
1136
20c82538 1137static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
8b004457 1138{
49a8a920 1139 struct crypt_config *cc = io->cc;
8b004457 1140 struct bio *clone;
93e605c2 1141
8b004457 1142 /*
59779079
MS
1143 * We need the original biovec array in order to decrypt
1144 * the whole bio data *afterwards* -- thanks to immutable
1145 * biovecs we don't need to worry about the block layer
1146 * modifying the biovec array; so leverage bio_clone_fast().
8b004457 1147 */
59779079 1148 clone = bio_clone_fast(io->base_bio, gfp, cc->bs);
7eaceacc 1149 if (!clone)
20c82538 1150 return 1;
8b004457 1151
20c82538
MB
1152 crypt_inc_pending(io);
1153
8b004457 1154 clone_init(io, clone);
4f024f37 1155 clone->bi_iter.bi_sector = cc->start + io->sector;
8b004457 1156
93e605c2 1157 generic_make_request(clone);
20c82538 1158 return 0;
8b004457
MB
1159}
1160
dc267621
MP
1161static void kcryptd_io_read_work(struct work_struct *work)
1162{
1163 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1164
1165 crypt_inc_pending(io);
1166 if (kcryptd_io_read(io, GFP_NOIO))
1167 io->error = -ENOMEM;
1168 crypt_dec_pending(io);
1169}
1170
1171static void kcryptd_queue_read(struct dm_crypt_io *io)
1172{
1173 struct crypt_config *cc = io->cc;
1174
1175 INIT_WORK(&io->work, kcryptd_io_read_work);
1176 queue_work(cc->io_queue, &io->work);
1177}
1178
4e4eef64
MB
1179static void kcryptd_io_write(struct dm_crypt_io *io)
1180{
95497a96 1181 struct bio *clone = io->ctx.bio_out;
dc267621 1182
95497a96 1183 generic_make_request(clone);
4e4eef64
MB
1184}
1185
b3c5fd30
MP
1186#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1187
dc267621 1188static int dmcrypt_write(void *data)
395b167c 1189{
dc267621 1190 struct crypt_config *cc = data;
b3c5fd30
MP
1191 struct dm_crypt_io *io;
1192
dc267621 1193 while (1) {
b3c5fd30 1194 struct rb_root write_tree;
dc267621 1195 struct blk_plug plug;
395b167c 1196
dc267621 1197 DECLARE_WAITQUEUE(wait, current);
395b167c 1198
dc267621
MP
1199 spin_lock_irq(&cc->write_thread_wait.lock);
1200continue_locked:
395b167c 1201
b3c5fd30 1202 if (!RB_EMPTY_ROOT(&cc->write_tree))
dc267621
MP
1203 goto pop_from_list;
1204
1205 __set_current_state(TASK_INTERRUPTIBLE);
1206 __add_wait_queue(&cc->write_thread_wait, &wait);
1207
1208 spin_unlock_irq(&cc->write_thread_wait.lock);
1209
1210 if (unlikely(kthread_should_stop())) {
1211 set_task_state(current, TASK_RUNNING);
1212 remove_wait_queue(&cc->write_thread_wait, &wait);
1213 break;
1214 }
1215
1216 schedule();
1217
1218 set_task_state(current, TASK_RUNNING);
1219 spin_lock_irq(&cc->write_thread_wait.lock);
1220 __remove_wait_queue(&cc->write_thread_wait, &wait);
1221 goto continue_locked;
1222
1223pop_from_list:
b3c5fd30
MP
1224 write_tree = cc->write_tree;
1225 cc->write_tree = RB_ROOT;
dc267621
MP
1226 spin_unlock_irq(&cc->write_thread_wait.lock);
1227
b3c5fd30
MP
1228 BUG_ON(rb_parent(write_tree.rb_node));
1229
1230 /*
1231 * Note: we cannot walk the tree here with rb_next because
1232 * the structures may be freed when kcryptd_io_write is called.
1233 */
dc267621
MP
1234 blk_start_plug(&plug);
1235 do {
b3c5fd30
MP
1236 io = crypt_io_from_node(rb_first(&write_tree));
1237 rb_erase(&io->rb_node, &write_tree);
dc267621 1238 kcryptd_io_write(io);
b3c5fd30 1239 } while (!RB_EMPTY_ROOT(&write_tree));
dc267621
MP
1240 blk_finish_plug(&plug);
1241 }
1242 return 0;
395b167c
AK
1243}
1244
72c6e7af 1245static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
4e4eef64 1246{
dec1cedf 1247 struct bio *clone = io->ctx.bio_out;
49a8a920 1248 struct crypt_config *cc = io->cc;
dc267621 1249 unsigned long flags;
b3c5fd30
MP
1250 sector_t sector;
1251 struct rb_node **rbp, *parent;
dec1cedf 1252
72c6e7af 1253 if (unlikely(io->error < 0)) {
dec1cedf
MB
1254 crypt_free_buffer_pages(cc, clone);
1255 bio_put(clone);
6c031f41 1256 crypt_dec_pending(io);
dec1cedf
MB
1257 return;
1258 }
1259
1260 /* crypt_convert should have filled the clone bio */
003b5c57 1261 BUG_ON(io->ctx.iter_out.bi_size);
dec1cedf 1262
4f024f37 1263 clone->bi_iter.bi_sector = cc->start + io->sector;
899c95d3 1264
0f5d8e6e
MP
1265 if (likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) {
1266 generic_make_request(clone);
1267 return;
1268 }
1269
dc267621 1270 spin_lock_irqsave(&cc->write_thread_wait.lock, flags);
b3c5fd30
MP
1271 rbp = &cc->write_tree.rb_node;
1272 parent = NULL;
1273 sector = io->sector;
1274 while (*rbp) {
1275 parent = *rbp;
1276 if (sector < crypt_io_from_node(parent)->sector)
1277 rbp = &(*rbp)->rb_left;
1278 else
1279 rbp = &(*rbp)->rb_right;
1280 }
1281 rb_link_node(&io->rb_node, parent, rbp);
1282 rb_insert_color(&io->rb_node, &cc->write_tree);
1283
dc267621
MP
1284 wake_up_locked(&cc->write_thread_wait);
1285 spin_unlock_irqrestore(&cc->write_thread_wait.lock, flags);
4e4eef64
MB
1286}
1287
fc5a5e9a 1288static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
8b004457 1289{
49a8a920 1290 struct crypt_config *cc = io->cc;
8b004457 1291 struct bio *clone;
c8081618 1292 int crypt_finished;
b635b00e 1293 sector_t sector = io->sector;
dec1cedf 1294 int r;
8b004457 1295
fc5a5e9a
MB
1296 /*
1297 * Prevent io from disappearing until this function completes.
1298 */
1299 crypt_inc_pending(io);
b635b00e 1300 crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
fc5a5e9a 1301
cf2f1abf
MP
1302 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1303 if (unlikely(!clone)) {
1304 io->error = -EIO;
1305 goto dec;
1306 }
c8081618 1307
cf2f1abf
MP
1308 io->ctx.bio_out = clone;
1309 io->ctx.iter_out = clone->bi_iter;
b635b00e 1310
cf2f1abf 1311 sector += bio_sectors(clone);
93e605c2 1312
cf2f1abf
MP
1313 crypt_inc_pending(io);
1314 r = crypt_convert(cc, &io->ctx);
1315 if (r)
1316 io->error = -EIO;
1317 crypt_finished = atomic_dec_and_test(&io->ctx.cc_pending);
933f01d4 1318
cf2f1abf
MP
1319 /* Encryption was already finished, submit io now */
1320 if (crypt_finished) {
1321 kcryptd_crypt_write_io_submit(io, 0);
1322 io->sector = sector;
93e605c2 1323 }
899c95d3 1324
cf2f1abf 1325dec:
899c95d3 1326 crypt_dec_pending(io);
84131db6
MB
1327}
1328
72c6e7af 1329static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
5742fd77 1330{
5742fd77
MB
1331 crypt_dec_pending(io);
1332}
1333
4e4eef64 1334static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
8b004457 1335{
49a8a920 1336 struct crypt_config *cc = io->cc;
5742fd77 1337 int r = 0;
1da177e4 1338
3e1a8bdd 1339 crypt_inc_pending(io);
3a7f6c99 1340
53017030 1341 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
0c395b0f 1342 io->sector);
1da177e4 1343
5742fd77 1344 r = crypt_convert(cc, &io->ctx);
72c6e7af
MP
1345 if (r < 0)
1346 io->error = -EIO;
5742fd77 1347
40b6229b 1348 if (atomic_dec_and_test(&io->ctx.cc_pending))
72c6e7af 1349 kcryptd_crypt_read_done(io);
3a7f6c99
MB
1350
1351 crypt_dec_pending(io);
1da177e4
LT
1352}
1353
95497a96
MB
1354static void kcryptd_async_done(struct crypto_async_request *async_req,
1355 int error)
1356{
b2174eeb
HY
1357 struct dm_crypt_request *dmreq = async_req->data;
1358 struct convert_context *ctx = dmreq->ctx;
95497a96 1359 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
49a8a920 1360 struct crypt_config *cc = io->cc;
95497a96 1361
54cea3f6
MB
1362 /*
1363 * A request from crypto driver backlog is going to be processed now,
1364 * finish the completion and continue in crypt_convert().
1365 * (Callback will be called for the second time for this request.)
1366 */
c0403ec0
RV
1367 if (error == -EINPROGRESS) {
1368 complete(&ctx->restart);
95497a96 1369 return;
c0403ec0 1370 }
95497a96 1371
2dc5327d
MB
1372 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
1373 error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq);
1374
72c6e7af
MP
1375 if (error < 0)
1376 io->error = -EIO;
1377
298a9fa0 1378 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
95497a96 1379
40b6229b 1380 if (!atomic_dec_and_test(&ctx->cc_pending))
c0403ec0 1381 return;
95497a96
MB
1382
1383 if (bio_data_dir(io->base_bio) == READ)
72c6e7af 1384 kcryptd_crypt_read_done(io);
95497a96 1385 else
72c6e7af 1386 kcryptd_crypt_write_io_submit(io, 1);
95497a96
MB
1387}
1388
395b167c 1389static void kcryptd_crypt(struct work_struct *work)
1da177e4 1390{
028867ac 1391 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
8b004457 1392
cabf08e4 1393 if (bio_data_dir(io->base_bio) == READ)
395b167c 1394 kcryptd_crypt_read_convert(io);
4e4eef64 1395 else
395b167c 1396 kcryptd_crypt_write_convert(io);
cabf08e4
MB
1397}
1398
395b167c 1399static void kcryptd_queue_crypt(struct dm_crypt_io *io)
cabf08e4 1400{
49a8a920 1401 struct crypt_config *cc = io->cc;
cabf08e4 1402
395b167c
AK
1403 INIT_WORK(&io->work, kcryptd_crypt);
1404 queue_work(cc->crypt_queue, &io->work);
1da177e4
LT
1405}
1406
1407/*
1408 * Decode key from its hex representation
1409 */
1410static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
1411{
1412 char buffer[3];
1da177e4
LT
1413 unsigned int i;
1414
1415 buffer[2] = '\0';
1416
8b004457 1417 for (i = 0; i < size; i++) {
1da177e4
LT
1418 buffer[0] = *hex++;
1419 buffer[1] = *hex++;
1420
1a66a08a 1421 if (kstrtou8(buffer, 16, &key[i]))
1da177e4
LT
1422 return -EINVAL;
1423 }
1424
1425 if (*hex != '\0')
1426 return -EINVAL;
1427
1428 return 0;
1429}
1430
fd2d231f 1431static void crypt_free_tfms(struct crypt_config *cc)
d1f96423 1432{
d1f96423
MB
1433 unsigned i;
1434
fd2d231f
MP
1435 if (!cc->tfms)
1436 return;
1437
d1f96423 1438 for (i = 0; i < cc->tfms_count; i++)
fd2d231f
MP
1439 if (cc->tfms[i] && !IS_ERR(cc->tfms[i])) {
1440 crypto_free_ablkcipher(cc->tfms[i]);
1441 cc->tfms[i] = NULL;
d1f96423 1442 }
fd2d231f
MP
1443
1444 kfree(cc->tfms);
1445 cc->tfms = NULL;
d1f96423
MB
1446}
1447
fd2d231f 1448static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
d1f96423 1449{
d1f96423
MB
1450 unsigned i;
1451 int err;
1452
fd2d231f
MP
1453 cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_ablkcipher *),
1454 GFP_KERNEL);
1455 if (!cc->tfms)
1456 return -ENOMEM;
1457
d1f96423 1458 for (i = 0; i < cc->tfms_count; i++) {
fd2d231f
MP
1459 cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
1460 if (IS_ERR(cc->tfms[i])) {
1461 err = PTR_ERR(cc->tfms[i]);
1462 crypt_free_tfms(cc);
d1f96423
MB
1463 return err;
1464 }
1465 }
1466
1467 return 0;
1468}
1469
c0297721
AK
1470static int crypt_setkey_allcpus(struct crypt_config *cc)
1471{
da31a078 1472 unsigned subkey_size;
fd2d231f
MP
1473 int err = 0, i, r;
1474
da31a078
MB
1475 /* Ignore extra keys (which are used for IV etc) */
1476 subkey_size = (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
1477
fd2d231f
MP
1478 for (i = 0; i < cc->tfms_count; i++) {
1479 r = crypto_ablkcipher_setkey(cc->tfms[i],
1480 cc->key + (i * subkey_size),
1481 subkey_size);
1482 if (r)
1483 err = r;
c0297721
AK
1484 }
1485
1486 return err;
1487}
1488
e48d4bbf
MB
1489static int crypt_set_key(struct crypt_config *cc, char *key)
1490{
de8be5ac
MB
1491 int r = -EINVAL;
1492 int key_string_len = strlen(key);
1493
69a8cfcd 1494 /* The key size may not be changed. */
de8be5ac
MB
1495 if (cc->key_size != (key_string_len >> 1))
1496 goto out;
e48d4bbf 1497
69a8cfcd
MB
1498 /* Hyphen (which gives a key_size of zero) means there is no key. */
1499 if (!cc->key_size && strcmp(key, "-"))
de8be5ac 1500 goto out;
e48d4bbf 1501
69a8cfcd 1502 if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
de8be5ac 1503 goto out;
e48d4bbf
MB
1504
1505 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1506
de8be5ac
MB
1507 r = crypt_setkey_allcpus(cc);
1508
1509out:
1510 /* Hex key string not needed after here, so wipe it. */
1511 memset(key, '0', key_string_len);
1512
1513 return r;
e48d4bbf
MB
1514}
1515
1516static int crypt_wipe_key(struct crypt_config *cc)
1517{
1518 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1519 memset(&cc->key, 0, cc->key_size * sizeof(u8));
c0297721
AK
1520
1521 return crypt_setkey_allcpus(cc);
e48d4bbf
MB
1522}
1523
28513fcc
MB
1524static void crypt_dtr(struct dm_target *ti)
1525{
1526 struct crypt_config *cc = ti->private;
1527
1528 ti->private = NULL;
1529
1530 if (!cc)
1531 return;
1532
dc267621
MP
1533 if (cc->write_thread)
1534 kthread_stop(cc->write_thread);
1535
28513fcc
MB
1536 if (cc->io_queue)
1537 destroy_workqueue(cc->io_queue);
1538 if (cc->crypt_queue)
1539 destroy_workqueue(cc->crypt_queue);
1540
fd2d231f
MP
1541 crypt_free_tfms(cc);
1542
28513fcc
MB
1543 if (cc->bs)
1544 bioset_free(cc->bs);
1545
1546 if (cc->page_pool)
1547 mempool_destroy(cc->page_pool);
1548 if (cc->req_pool)
1549 mempool_destroy(cc->req_pool);
28513fcc
MB
1550
1551 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
1552 cc->iv_gen_ops->dtr(cc);
1553
28513fcc
MB
1554 if (cc->dev)
1555 dm_put_device(ti, cc->dev);
1556
5ebaee6d 1557 kzfree(cc->cipher);
7dbcd137 1558 kzfree(cc->cipher_string);
28513fcc
MB
1559
1560 /* Must zero key material before freeing */
1561 kzfree(cc);
1562}
1563
5ebaee6d
MB
1564static int crypt_ctr_cipher(struct dm_target *ti,
1565 char *cipher_in, char *key)
1da177e4 1566{
5ebaee6d 1567 struct crypt_config *cc = ti->private;
d1f96423 1568 char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
5ebaee6d 1569 char *cipher_api = NULL;
fd2d231f 1570 int ret = -EINVAL;
31998ef1 1571 char dummy;
1da177e4 1572
5ebaee6d
MB
1573 /* Convert to crypto api definition? */
1574 if (strchr(cipher_in, '(')) {
1575 ti->error = "Bad cipher specification";
1da177e4
LT
1576 return -EINVAL;
1577 }
1578
7dbcd137
MB
1579 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
1580 if (!cc->cipher_string)
1581 goto bad_mem;
1582
5ebaee6d
MB
1583 /*
1584 * Legacy dm-crypt cipher specification
d1f96423 1585 * cipher[:keycount]-mode-iv:ivopts
5ebaee6d
MB
1586 */
1587 tmp = cipher_in;
d1f96423
MB
1588 keycount = strsep(&tmp, "-");
1589 cipher = strsep(&keycount, ":");
1590
1591 if (!keycount)
1592 cc->tfms_count = 1;
31998ef1 1593 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
d1f96423
MB
1594 !is_power_of_2(cc->tfms_count)) {
1595 ti->error = "Bad cipher key count specification";
1596 return -EINVAL;
1597 }
1598 cc->key_parts = cc->tfms_count;
da31a078 1599 cc->key_extra_size = 0;
5ebaee6d
MB
1600
1601 cc->cipher = kstrdup(cipher, GFP_KERNEL);
1602 if (!cc->cipher)
1603 goto bad_mem;
1604
1da177e4
LT
1605 chainmode = strsep(&tmp, "-");
1606 ivopts = strsep(&tmp, "-");
1607 ivmode = strsep(&ivopts, ":");
1608
1609 if (tmp)
5ebaee6d 1610 DMWARN("Ignoring unexpected additional cipher options");
1da177e4 1611
7dbcd137
MB
1612 /*
1613 * For compatibility with the original dm-crypt mapping format, if
1614 * only the cipher name is supplied, use cbc-plain.
1615 */
5ebaee6d 1616 if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) {
1da177e4
LT
1617 chainmode = "cbc";
1618 ivmode = "plain";
1619 }
1620
d1806f6a 1621 if (strcmp(chainmode, "ecb") && !ivmode) {
5ebaee6d
MB
1622 ti->error = "IV mechanism required";
1623 return -EINVAL;
1da177e4
LT
1624 }
1625
5ebaee6d
MB
1626 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
1627 if (!cipher_api)
1628 goto bad_mem;
1629
1630 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
1631 "%s(%s)", chainmode, cipher);
1632 if (ret < 0) {
1633 kfree(cipher_api);
1634 goto bad_mem;
1da177e4
LT
1635 }
1636
5ebaee6d 1637 /* Allocate cipher */
fd2d231f
MP
1638 ret = crypt_alloc_tfms(cc, cipher_api);
1639 if (ret < 0) {
1640 ti->error = "Error allocating crypto tfm";
1641 goto bad;
1da177e4 1642 }
1da177e4 1643
5ebaee6d 1644 /* Initialize IV */
c0297721 1645 cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
5ebaee6d
MB
1646 if (cc->iv_size)
1647 /* at least a 64 bit sector number should fit in our buffer */
1648 cc->iv_size = max(cc->iv_size,
1649 (unsigned int)(sizeof(u64) / sizeof(u8)));
1650 else if (ivmode) {
1651 DMWARN("Selected cipher does not support IVs");
1652 ivmode = NULL;
1653 }
1654
1655 /* Choose ivmode, see comments at iv code. */
1da177e4
LT
1656 if (ivmode == NULL)
1657 cc->iv_gen_ops = NULL;
1658 else if (strcmp(ivmode, "plain") == 0)
1659 cc->iv_gen_ops = &crypt_iv_plain_ops;
61afef61
MB
1660 else if (strcmp(ivmode, "plain64") == 0)
1661 cc->iv_gen_ops = &crypt_iv_plain64_ops;
1da177e4
LT
1662 else if (strcmp(ivmode, "essiv") == 0)
1663 cc->iv_gen_ops = &crypt_iv_essiv_ops;
48527fa7
RS
1664 else if (strcmp(ivmode, "benbi") == 0)
1665 cc->iv_gen_ops = &crypt_iv_benbi_ops;
46b47730
LN
1666 else if (strcmp(ivmode, "null") == 0)
1667 cc->iv_gen_ops = &crypt_iv_null_ops;
34745785
MB
1668 else if (strcmp(ivmode, "lmk") == 0) {
1669 cc->iv_gen_ops = &crypt_iv_lmk_ops;
ed04d981
MB
1670 /*
1671 * Version 2 and 3 is recognised according
34745785
MB
1672 * to length of provided multi-key string.
1673 * If present (version 3), last key is used as IV seed.
ed04d981 1674 * All keys (including IV seed) are always the same size.
34745785 1675 */
da31a078 1676 if (cc->key_size % cc->key_parts) {
34745785 1677 cc->key_parts++;
da31a078
MB
1678 cc->key_extra_size = cc->key_size / cc->key_parts;
1679 }
ed04d981
MB
1680 } else if (strcmp(ivmode, "tcw") == 0) {
1681 cc->iv_gen_ops = &crypt_iv_tcw_ops;
1682 cc->key_parts += 2; /* IV + whitening */
1683 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
34745785 1684 } else {
5ebaee6d 1685 ret = -EINVAL;
72d94861 1686 ti->error = "Invalid IV mode";
28513fcc 1687 goto bad;
1da177e4
LT
1688 }
1689
da31a078
MB
1690 /* Initialize and set key */
1691 ret = crypt_set_key(cc, key);
1692 if (ret < 0) {
1693 ti->error = "Error decoding and setting key";
1694 goto bad;
1695 }
1696
28513fcc
MB
1697 /* Allocate IV */
1698 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
1699 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
1700 if (ret < 0) {
1701 ti->error = "Error creating IV";
1702 goto bad;
1703 }
1704 }
1da177e4 1705
28513fcc
MB
1706 /* Initialize IV (set keys for ESSIV etc) */
1707 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
1708 ret = cc->iv_gen_ops->init(cc);
1709 if (ret < 0) {
1710 ti->error = "Error initialising IV";
1711 goto bad;
1712 }
b95bf2d3
MB
1713 }
1714
5ebaee6d
MB
1715 ret = 0;
1716bad:
1717 kfree(cipher_api);
1718 return ret;
1719
1720bad_mem:
1721 ti->error = "Cannot allocate cipher strings";
1722 return -ENOMEM;
1723}
1724
1725/*
1726 * Construct an encryption mapping:
1727 * <cipher> <key> <iv_offset> <dev_path> <start>
1728 */
1729static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
1730{
1731 struct crypt_config *cc;
772ae5f5 1732 unsigned int key_size, opt_params;
5ebaee6d
MB
1733 unsigned long long tmpll;
1734 int ret;
d49ec52f 1735 size_t iv_size_padding;
772ae5f5
MB
1736 struct dm_arg_set as;
1737 const char *opt_string;
31998ef1 1738 char dummy;
772ae5f5
MB
1739
1740 static struct dm_arg _args[] = {
0f5d8e6e 1741 {0, 3, "Invalid number of feature args"},
772ae5f5 1742 };
5ebaee6d 1743
772ae5f5 1744 if (argc < 5) {
5ebaee6d
MB
1745 ti->error = "Not enough arguments";
1746 return -EINVAL;
1da177e4
LT
1747 }
1748
5ebaee6d
MB
1749 key_size = strlen(argv[1]) >> 1;
1750
1751 cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);
1752 if (!cc) {
1753 ti->error = "Cannot allocate encryption context";
1754 return -ENOMEM;
1755 }
69a8cfcd 1756 cc->key_size = key_size;
5ebaee6d
MB
1757
1758 ti->private = cc;
1759 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
1760 if (ret < 0)
1761 goto bad;
1762
ddd42edf 1763 cc->dmreq_start = sizeof(struct ablkcipher_request);
c0297721 1764 cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
d49ec52f
MP
1765 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
1766
1767 if (crypto_ablkcipher_alignmask(any_tfm(cc)) < CRYPTO_MINALIGN) {
1768 /* Allocate the padding exactly */
1769 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
1770 & crypto_ablkcipher_alignmask(any_tfm(cc));
1771 } else {
1772 /*
1773 * If the cipher requires greater alignment than kmalloc
1774 * alignment, we don't know the exact position of the
1775 * initialization vector. We must assume worst case.
1776 */
1777 iv_size_padding = crypto_ablkcipher_alignmask(any_tfm(cc));
1778 }
ddd42edf 1779
94f5e024 1780 ret = -ENOMEM;
ddd42edf 1781 cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
d49ec52f 1782 sizeof(struct dm_crypt_request) + iv_size_padding + cc->iv_size);
ddd42edf
MB
1783 if (!cc->req_pool) {
1784 ti->error = "Cannot allocate crypt request mempool";
28513fcc 1785 goto bad;
ddd42edf 1786 }
ddd42edf 1787
298a9fa0 1788 cc->per_bio_data_size = ti->per_bio_data_size =
d49ec52f
MP
1789 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start +
1790 sizeof(struct dm_crypt_request) + iv_size_padding + cc->iv_size,
1791 ARCH_KMALLOC_MINALIGN);
298a9fa0 1792
cf2f1abf 1793 cc->page_pool = mempool_create_page_pool(BIO_MAX_PAGES, 0);
1da177e4 1794 if (!cc->page_pool) {
72d94861 1795 ti->error = "Cannot allocate page mempool";
28513fcc 1796 goto bad;
1da177e4
LT
1797 }
1798
bb799ca0 1799 cc->bs = bioset_create(MIN_IOS, 0);
6a24c718
MB
1800 if (!cc->bs) {
1801 ti->error = "Cannot allocate crypt bioset";
28513fcc 1802 goto bad;
6a24c718
MB
1803 }
1804
7145c241
MP
1805 mutex_init(&cc->bio_alloc_lock);
1806
28513fcc 1807 ret = -EINVAL;
31998ef1 1808 if (sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) {
72d94861 1809 ti->error = "Invalid iv_offset sector";
28513fcc 1810 goto bad;
1da177e4 1811 }
4ee218cd 1812 cc->iv_offset = tmpll;
1da177e4 1813
28513fcc
MB
1814 if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) {
1815 ti->error = "Device lookup failed";
1816 goto bad;
1817 }
1818
31998ef1 1819 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) {
72d94861 1820 ti->error = "Invalid device sector";
28513fcc 1821 goto bad;
1da177e4 1822 }
4ee218cd 1823 cc->start = tmpll;
1da177e4 1824
772ae5f5
MB
1825 argv += 5;
1826 argc -= 5;
1827
1828 /* Optional parameters */
1829 if (argc) {
1830 as.argc = argc;
1831 as.argv = argv;
1832
1833 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
1834 if (ret)
1835 goto bad;
1836
44c144f9 1837 ret = -EINVAL;
f3396c58
MP
1838 while (opt_params--) {
1839 opt_string = dm_shift_arg(&as);
1840 if (!opt_string) {
1841 ti->error = "Not enough feature arguments";
1842 goto bad;
1843 }
772ae5f5 1844
f3396c58
MP
1845 if (!strcasecmp(opt_string, "allow_discards"))
1846 ti->num_discard_bios = 1;
1847
1848 else if (!strcasecmp(opt_string, "same_cpu_crypt"))
1849 set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
1850
0f5d8e6e
MP
1851 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
1852 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
1853
f3396c58
MP
1854 else {
1855 ti->error = "Invalid feature arguments";
1856 goto bad;
1857 }
772ae5f5
MB
1858 }
1859 }
1860
28513fcc 1861 ret = -ENOMEM;
670368a8 1862 cc->io_queue = alloc_workqueue("kcryptd_io", WQ_MEM_RECLAIM, 1);
cabf08e4
MB
1863 if (!cc->io_queue) {
1864 ti->error = "Couldn't create kcryptd io queue";
28513fcc 1865 goto bad;
cabf08e4
MB
1866 }
1867
f3396c58
MP
1868 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
1869 cc->crypt_queue = alloc_workqueue("kcryptd", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
1870 else
1871 cc->crypt_queue = alloc_workqueue("kcryptd", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
1872 num_online_cpus());
cabf08e4 1873 if (!cc->crypt_queue) {
9934a8be 1874 ti->error = "Couldn't create kcryptd queue";
28513fcc 1875 goto bad;
9934a8be
MB
1876 }
1877
dc267621 1878 init_waitqueue_head(&cc->write_thread_wait);
b3c5fd30 1879 cc->write_tree = RB_ROOT;
dc267621
MP
1880
1881 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write");
1882 if (IS_ERR(cc->write_thread)) {
1883 ret = PTR_ERR(cc->write_thread);
1884 cc->write_thread = NULL;
1885 ti->error = "Couldn't spawn write thread";
1886 goto bad;
1887 }
1888 wake_up_process(cc->write_thread);
1889
55a62eef 1890 ti->num_flush_bios = 1;
0ac55489 1891 ti->discard_zeroes_data_unsupported = true;
983c7db3 1892
1da177e4
LT
1893 return 0;
1894
28513fcc
MB
1895bad:
1896 crypt_dtr(ti);
1897 return ret;
1da177e4
LT
1898}
1899
7de3ee57 1900static int crypt_map(struct dm_target *ti, struct bio *bio)
1da177e4 1901{
028867ac 1902 struct dm_crypt_io *io;
49a8a920 1903 struct crypt_config *cc = ti->private;
647c7db1 1904
772ae5f5
MB
1905 /*
1906 * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
1907 * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight
1908 * - for REQ_DISCARD caller must use flush if IO ordering matters
1909 */
1910 if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
647c7db1 1911 bio->bi_bdev = cc->dev->bdev;
772ae5f5 1912 if (bio_sectors(bio))
4f024f37
KO
1913 bio->bi_iter.bi_sector = cc->start +
1914 dm_target_offset(ti, bio->bi_iter.bi_sector);
647c7db1
MP
1915 return DM_MAPIO_REMAPPED;
1916 }
1da177e4 1917
298a9fa0
MP
1918 io = dm_per_bio_data(bio, cc->per_bio_data_size);
1919 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
1920 io->ctx.req = (struct ablkcipher_request *)(io + 1);
cabf08e4 1921
20c82538
MB
1922 if (bio_data_dir(io->base_bio) == READ) {
1923 if (kcryptd_io_read(io, GFP_NOWAIT))
dc267621 1924 kcryptd_queue_read(io);
20c82538 1925 } else
cabf08e4 1926 kcryptd_queue_crypt(io);
1da177e4 1927
d2a7ad29 1928 return DM_MAPIO_SUBMITTED;
1da177e4
LT
1929}
1930
fd7c092e
MP
1931static void crypt_status(struct dm_target *ti, status_type_t type,
1932 unsigned status_flags, char *result, unsigned maxlen)
1da177e4 1933{
5ebaee6d 1934 struct crypt_config *cc = ti->private;
fd7c092e 1935 unsigned i, sz = 0;
f3396c58 1936 int num_feature_args = 0;
1da177e4
LT
1937
1938 switch (type) {
1939 case STATUSTYPE_INFO:
1940 result[0] = '\0';
1941 break;
1942
1943 case STATUSTYPE_TABLE:
7dbcd137 1944 DMEMIT("%s ", cc->cipher_string);
1da177e4 1945
fd7c092e
MP
1946 if (cc->key_size > 0)
1947 for (i = 0; i < cc->key_size; i++)
1948 DMEMIT("%02x", cc->key[i]);
1949 else
1950 DMEMIT("-");
1da177e4 1951
4ee218cd
AM
1952 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
1953 cc->dev->name, (unsigned long long)cc->start);
772ae5f5 1954
f3396c58
MP
1955 num_feature_args += !!ti->num_discard_bios;
1956 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
0f5d8e6e 1957 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
f3396c58
MP
1958 if (num_feature_args) {
1959 DMEMIT(" %d", num_feature_args);
1960 if (ti->num_discard_bios)
1961 DMEMIT(" allow_discards");
1962 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
1963 DMEMIT(" same_cpu_crypt");
0f5d8e6e
MP
1964 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
1965 DMEMIT(" submit_from_crypt_cpus");
f3396c58 1966 }
772ae5f5 1967
1da177e4
LT
1968 break;
1969 }
1da177e4
LT
1970}
1971
e48d4bbf
MB
1972static void crypt_postsuspend(struct dm_target *ti)
1973{
1974 struct crypt_config *cc = ti->private;
1975
1976 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1977}
1978
1979static int crypt_preresume(struct dm_target *ti)
1980{
1981 struct crypt_config *cc = ti->private;
1982
1983 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
1984 DMERR("aborting resume - crypt key is not set.");
1985 return -EAGAIN;
1986 }
1987
1988 return 0;
1989}
1990
1991static void crypt_resume(struct dm_target *ti)
1992{
1993 struct crypt_config *cc = ti->private;
1994
1995 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1996}
1997
1998/* Message interface
1999 * key set <key>
2000 * key wipe
2001 */
2002static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
2003{
2004 struct crypt_config *cc = ti->private;
542da317 2005 int ret = -EINVAL;
e48d4bbf
MB
2006
2007 if (argc < 2)
2008 goto error;
2009
498f0103 2010 if (!strcasecmp(argv[0], "key")) {
e48d4bbf
MB
2011 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
2012 DMWARN("not suspended during key manipulation.");
2013 return -EINVAL;
2014 }
498f0103 2015 if (argc == 3 && !strcasecmp(argv[1], "set")) {
542da317
MB
2016 ret = crypt_set_key(cc, argv[2]);
2017 if (ret)
2018 return ret;
2019 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
2020 ret = cc->iv_gen_ops->init(cc);
2021 return ret;
2022 }
498f0103 2023 if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
542da317
MB
2024 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2025 ret = cc->iv_gen_ops->wipe(cc);
2026 if (ret)
2027 return ret;
2028 }
e48d4bbf 2029 return crypt_wipe_key(cc);
542da317 2030 }
e48d4bbf
MB
2031 }
2032
2033error:
2034 DMWARN("unrecognised message received.");
2035 return -EINVAL;
2036}
2037
d41e26b9
MB
2038static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
2039 struct bio_vec *biovec, int max_size)
2040{
2041 struct crypt_config *cc = ti->private;
2042 struct request_queue *q = bdev_get_queue(cc->dev->bdev);
2043
2044 if (!q->merge_bvec_fn)
2045 return max_size;
2046
2047 bvm->bi_bdev = cc->dev->bdev;
b441a262 2048 bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector);
d41e26b9
MB
2049
2050 return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
2051}
2052
af4874e0
MS
2053static int crypt_iterate_devices(struct dm_target *ti,
2054 iterate_devices_callout_fn fn, void *data)
2055{
2056 struct crypt_config *cc = ti->private;
2057
5dea271b 2058 return fn(ti, cc->dev, cc->start, ti->len, data);
af4874e0
MS
2059}
2060
1da177e4
LT
2061static struct target_type crypt_target = {
2062 .name = "crypt",
f3396c58 2063 .version = {1, 14, 0},
1da177e4
LT
2064 .module = THIS_MODULE,
2065 .ctr = crypt_ctr,
2066 .dtr = crypt_dtr,
2067 .map = crypt_map,
2068 .status = crypt_status,
e48d4bbf
MB
2069 .postsuspend = crypt_postsuspend,
2070 .preresume = crypt_preresume,
2071 .resume = crypt_resume,
2072 .message = crypt_message,
d41e26b9 2073 .merge = crypt_merge,
af4874e0 2074 .iterate_devices = crypt_iterate_devices,
1da177e4
LT
2075};
2076
2077static int __init dm_crypt_init(void)
2078{
2079 int r;
2080
1da177e4 2081 r = dm_register_target(&crypt_target);
94f5e024 2082 if (r < 0)
72d94861 2083 DMERR("register failed %d", r);
1da177e4 2084
1da177e4
LT
2085 return r;
2086}
2087
2088static void __exit dm_crypt_exit(void)
2089{
10d3bd09 2090 dm_unregister_target(&crypt_target);
1da177e4
LT
2091}
2092
2093module_init(dm_crypt_init);
2094module_exit(dm_crypt_exit);
2095
bf14299f 2096MODULE_AUTHOR("Jana Saout <jana@saout.de>");
1da177e4
LT
2097MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
2098MODULE_LICENSE("GPL");