?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Merge tag 'fixes-for-v4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux/fpc-iii.git] / drivers / md / dm-crypt.c
blob9fc12f556534b71ccbb91848d4eb9dc7395bd8fa
1 /*
2 * Copyright (C) 2003 Jana Saout <jana@saout.de>
3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
4 * Copyright (C) 2006-2017 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2013-2017 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 <keys/user-type.h>
38
39 #include <linux/device-mapper.h>
40
41 #define DM_MSG_PREFIX "crypt"
42
43 /*
44 * context holding the current state of a multi-part conversion
45 */
46 struct convert_context {
47 struct completion restart;
48 struct bio *bio_in;
49 struct bio *bio_out;
50 struct bvec_iter iter_in;
51 struct bvec_iter iter_out;
52 sector_t cc_sector;
53 atomic_t cc_pending;
54 union {
55 struct skcipher_request *req;
56 struct aead_request *req_aead;
57 } r;
58
59 };
60
61 /*
62 * per bio private data
63 */
64 struct dm_crypt_io {
65 struct crypt_config *cc;
66 struct bio *base_bio;
67 u8 *integrity_metadata;
68 bool integrity_metadata_from_pool;
69 struct work_struct work;
70
71 struct convert_context ctx;
72
73 atomic_t io_pending;
74 blk_status_t error;
75 sector_t sector;
76
77 struct rb_node rb_node;
78 } CRYPTO_MINALIGN_ATTR;
79
80 struct dm_crypt_request {
81 struct convert_context *ctx;
82 struct scatterlist sg_in[4];
83 struct scatterlist sg_out[4];
84 sector_t iv_sector;
85 };
86
87 struct crypt_config;
88
89 struct crypt_iv_operations {
90 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
91 const char *opts);
92 void (*dtr)(struct crypt_config *cc);
93 int (*init)(struct crypt_config *cc);
94 int (*wipe)(struct crypt_config *cc);
95 int (*generator)(struct crypt_config *cc, u8 *iv,
96 struct dm_crypt_request *dmreq);
97 int (*post)(struct crypt_config *cc, u8 *iv,
98 struct dm_crypt_request *dmreq);
99 };
100
101 struct iv_essiv_private {
102 struct crypto_ahash *hash_tfm;
103 u8 *salt;
104 };
105
106 struct iv_benbi_private {
107 int shift;
108 };
109
110 #define LMK_SEED_SIZE 64 /* hash + 0 */
111 struct iv_lmk_private {
112 struct crypto_shash *hash_tfm;
113 u8 *seed;
114 };
115
116 #define TCW_WHITENING_SIZE 16
117 struct iv_tcw_private {
118 struct crypto_shash *crc32_tfm;
119 u8 *iv_seed;
120 u8 *whitening;
121 };
122
123 /*
124 * Crypt: maps a linear range of a block device
125 * and encrypts / decrypts at the same time.
126 */
127 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
128 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD };
129
130 enum cipher_flags {
131 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cihper */
132 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */
133 };
134
135 /*
136 * The fields in here must be read only after initialization.
137 */
138 struct crypt_config {
139 struct dm_dev *dev;
140 sector_t start;
141
142 /*
143 * pool for per bio private data, crypto requests,
144 * encryption requeusts/buffer pages and integrity tags
145 */
146 mempool_t *req_pool;
147 mempool_t *page_pool;
148 mempool_t *tag_pool;
149 unsigned tag_pool_max_sectors;
150
151 struct bio_set *bs;
152 struct mutex bio_alloc_lock;
153
154 struct workqueue_struct *io_queue;
155 struct workqueue_struct *crypt_queue;
156
157 struct task_struct *write_thread;
158 wait_queue_head_t write_thread_wait;
159 struct rb_root write_tree;
160
161 char *cipher;
162 char *cipher_string;
163 char *cipher_auth;
164 char *key_string;
165
166 const struct crypt_iv_operations *iv_gen_ops;
167 union {
168 struct iv_essiv_private essiv;
169 struct iv_benbi_private benbi;
170 struct iv_lmk_private lmk;
171 struct iv_tcw_private tcw;
172 } iv_gen_private;
173 sector_t iv_offset;
174 unsigned int iv_size;
175 unsigned short int sector_size;
176 unsigned char sector_shift;
177
178 /* ESSIV: struct crypto_cipher *essiv_tfm */
179 void *iv_private;
180 union {
181 struct crypto_skcipher **tfms;
182 struct crypto_aead **tfms_aead;
183 } cipher_tfm;
184 unsigned tfms_count;
185 unsigned long cipher_flags;
186
187 /*
188 * Layout of each crypto request:
189 *
190 * struct skcipher_request
191 * context
192 * padding
193 * struct dm_crypt_request
194 * padding
195 * IV
196 *
197 * The padding is added so that dm_crypt_request and the IV are
198 * correctly aligned.
199 */
200 unsigned int dmreq_start;
201
202 unsigned int per_bio_data_size;
203
204 unsigned long flags;
205 unsigned int key_size;
206 unsigned int key_parts; /* independent parts in key buffer */
207 unsigned int key_extra_size; /* additional keys length */
208 unsigned int key_mac_size; /* MAC key size for authenc(...) */
209
210 unsigned int integrity_tag_size;
211 unsigned int integrity_iv_size;
212 unsigned int on_disk_tag_size;
213
214 u8 *authenc_key; /* space for keys in authenc() format (if used) */
215 u8 key[0];
216 };
217
218 #define MIN_IOS 64
219 #define MAX_TAG_SIZE 480
220 #define POOL_ENTRY_SIZE 512
221
222 static void clone_init(struct dm_crypt_io *, struct bio *);
223 static void kcryptd_queue_crypt(struct dm_crypt_io *io);
224 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
225 struct scatterlist *sg);
226
227 /*
228 * Use this to access cipher attributes that are independent of the key.
229 */
230 static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
231 {
232 return cc->cipher_tfm.tfms[0];
233 }
234
235 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
236 {
237 return cc->cipher_tfm.tfms_aead[0];
238 }
239
240 /*
241 * Different IV generation algorithms:
242 *
243 * plain: the initial vector is the 32-bit little-endian version of the sector
244 * number, padded with zeros if necessary.
245 *
246 * plain64: the initial vector is the 64-bit little-endian version of the sector
247 * number, padded with zeros if necessary.
248 *
249 * plain64be: the initial vector is the 64-bit big-endian version of the sector
250 * number, padded with zeros if necessary.
251 *
252 * essiv: "encrypted sector|salt initial vector", the sector number is
253 * encrypted with the bulk cipher using a salt as key. The salt
254 * should be derived from the bulk cipher's key via hashing.
255 *
256 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
257 * (needed for LRW-32-AES and possible other narrow block modes)
258 *
259 * null: the initial vector is always zero. Provides compatibility with
260 * obsolete loop_fish2 devices. Do not use for new devices.
261 *
262 * lmk: Compatible implementation of the block chaining mode used
263 * by the Loop-AES block device encryption system
264 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
265 * It operates on full 512 byte sectors and uses CBC
266 * with an IV derived from the sector number, the data and
267 * optionally extra IV seed.
268 * This means that after decryption the first block
269 * of sector must be tweaked according to decrypted data.
270 * Loop-AES can use three encryption schemes:
271 * version 1: is plain aes-cbc mode
272 * version 2: uses 64 multikey scheme with lmk IV generator
273 * version 3: the same as version 2 with additional IV seed
274 * (it uses 65 keys, last key is used as IV seed)
275 *
276 * tcw: Compatible implementation of the block chaining mode used
277 * by the TrueCrypt device encryption system (prior to version 4.1).
278 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
279 * It operates on full 512 byte sectors and uses CBC
280 * with an IV derived from initial key and the sector number.
281 * In addition, whitening value is applied on every sector, whitening
282 * is calculated from initial key, sector number and mixed using CRC32.
283 * Note that this encryption scheme is vulnerable to watermarking attacks
284 * and should be used for old compatible containers access only.
285 *
286 * plumb: unimplemented, see:
287 * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
288 */
289
290 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
291 struct dm_crypt_request *dmreq)
292 {
293 memset(iv, 0, cc->iv_size);
294 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
295
296 return 0;
297 }
298
299 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
300 struct dm_crypt_request *dmreq)
301 {
302 memset(iv, 0, cc->iv_size);
303 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
304
305 return 0;
306 }
307
308 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
309 struct dm_crypt_request *dmreq)
310 {
311 memset(iv, 0, cc->iv_size);
312 /* iv_size is at least of size u64; usually it is 16 bytes */
313 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
314
315 return 0;
316 }
317
318 /* Initialise ESSIV - compute salt but no local memory allocations */
319 static int crypt_iv_essiv_init(struct crypt_config *cc)
320 {
321 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
322 AHASH_REQUEST_ON_STACK(req, essiv->hash_tfm);
323 struct scatterlist sg;
324 struct crypto_cipher *essiv_tfm;
325 int err;
326
327 sg_init_one(&sg, cc->key, cc->key_size);
328 ahash_request_set_tfm(req, essiv->hash_tfm);
329 ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL);
330 ahash_request_set_crypt(req, &sg, essiv->salt, cc->key_size);
331
332 err = crypto_ahash_digest(req);
333 ahash_request_zero(req);
334 if (err)
335 return err;
336
337 essiv_tfm = cc->iv_private;
338
339 err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
340 crypto_ahash_digestsize(essiv->hash_tfm));
341 if (err)
342 return err;
343
344 return 0;
345 }
346
347 /* Wipe salt and reset key derived from volume key */
348 static int crypt_iv_essiv_wipe(struct crypt_config *cc)
349 {
350 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
351 unsigned salt_size = crypto_ahash_digestsize(essiv->hash_tfm);
352 struct crypto_cipher *essiv_tfm;
353 int r, err = 0;
354
355 memset(essiv->salt, 0, salt_size);
356
357 essiv_tfm = cc->iv_private;
358 r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
359 if (r)
360 err = r;
361
362 return err;
363 }
364
365 /* Allocate the cipher for ESSIV */
366 static struct crypto_cipher *alloc_essiv_cipher(struct crypt_config *cc,
367 struct dm_target *ti,
368 const u8 *salt,
369 unsigned int saltsize)
370 {
371 struct crypto_cipher *essiv_tfm;
372 int err;
373
374 /* Setup the essiv_tfm with the given salt */
375 essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
376 if (IS_ERR(essiv_tfm)) {
377 ti->error = "Error allocating crypto tfm for ESSIV";
378 return essiv_tfm;
379 }
380
381 if (crypto_cipher_blocksize(essiv_tfm) != cc->iv_size) {
382 ti->error = "Block size of ESSIV cipher does "
383 "not match IV size of block cipher";
384 crypto_free_cipher(essiv_tfm);
385 return ERR_PTR(-EINVAL);
386 }
387
388 err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
389 if (err) {
390 ti->error = "Failed to set key for ESSIV cipher";
391 crypto_free_cipher(essiv_tfm);
392 return ERR_PTR(err);
393 }
394
395 return essiv_tfm;
396 }
397
398 static void crypt_iv_essiv_dtr(struct crypt_config *cc)
399 {
400 struct crypto_cipher *essiv_tfm;
401 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
402
403 crypto_free_ahash(essiv->hash_tfm);
404 essiv->hash_tfm = NULL;
405
406 kzfree(essiv->salt);
407 essiv->salt = NULL;
408
409 essiv_tfm = cc->iv_private;
410
411 if (essiv_tfm)
412 crypto_free_cipher(essiv_tfm);
413
414 cc->iv_private = NULL;
415 }
416
417 static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
418 const char *opts)
419 {
420 struct crypto_cipher *essiv_tfm = NULL;
421 struct crypto_ahash *hash_tfm = NULL;
422 u8 *salt = NULL;
423 int err;
424
425 if (!opts) {
426 ti->error = "Digest algorithm missing for ESSIV mode";
427 return -EINVAL;
428 }
429
430 /* Allocate hash algorithm */
431 hash_tfm = crypto_alloc_ahash(opts, 0, CRYPTO_ALG_ASYNC);
432 if (IS_ERR(hash_tfm)) {
433 ti->error = "Error initializing ESSIV hash";
434 err = PTR_ERR(hash_tfm);
435 goto bad;
436 }
437
438 salt = kzalloc(crypto_ahash_digestsize(hash_tfm), GFP_KERNEL);
439 if (!salt) {
440 ti->error = "Error kmallocing salt storage in ESSIV";
441 err = -ENOMEM;
442 goto bad;
443 }
444
445 cc->iv_gen_private.essiv.salt = salt;
446 cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
447
448 essiv_tfm = alloc_essiv_cipher(cc, ti, salt,
449 crypto_ahash_digestsize(hash_tfm));
450 if (IS_ERR(essiv_tfm)) {
451 crypt_iv_essiv_dtr(cc);
452 return PTR_ERR(essiv_tfm);
453 }
454 cc->iv_private = essiv_tfm;
455
456 return 0;
457
458 bad:
459 if (hash_tfm && !IS_ERR(hash_tfm))
460 crypto_free_ahash(hash_tfm);
461 kfree(salt);
462 return err;
463 }
464
465 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
466 struct dm_crypt_request *dmreq)
467 {
468 struct crypto_cipher *essiv_tfm = cc->iv_private;
469
470 memset(iv, 0, cc->iv_size);
471 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
472 crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
473
474 return 0;
475 }
476
477 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
478 const char *opts)
479 {
480 unsigned bs = crypto_skcipher_blocksize(any_tfm(cc));
481 int log = ilog2(bs);
482
483 /* we need to calculate how far we must shift the sector count
484 * to get the cipher block count, we use this shift in _gen */
485
486 if (1 << log != bs) {
487 ti->error = "cypher blocksize is not a power of 2";
488 return -EINVAL;
489 }
490
491 if (log > 9) {
492 ti->error = "cypher blocksize is > 512";
493 return -EINVAL;
494 }
495
496 cc->iv_gen_private.benbi.shift = 9 - log;
497
498 return 0;
499 }
500
501 static void crypt_iv_benbi_dtr(struct crypt_config *cc)
502 {
503 }
504
505 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
506 struct dm_crypt_request *dmreq)
507 {
508 __be64 val;
509
510 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
511
512 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
513 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
514
515 return 0;
516 }
517
518 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
519 struct dm_crypt_request *dmreq)
520 {
521 memset(iv, 0, cc->iv_size);
522
523 return 0;
524 }
525
526 static void crypt_iv_lmk_dtr(struct crypt_config *cc)
527 {
528 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
529
530 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
531 crypto_free_shash(lmk->hash_tfm);
532 lmk->hash_tfm = NULL;
533
534 kzfree(lmk->seed);
535 lmk->seed = NULL;
536 }
537
538 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
539 const char *opts)
540 {
541 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
542
543 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
544 ti->error = "Unsupported sector size for LMK";
545 return -EINVAL;
546 }
547
548 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
549 if (IS_ERR(lmk->hash_tfm)) {
550 ti->error = "Error initializing LMK hash";
551 return PTR_ERR(lmk->hash_tfm);
552 }
553
554 /* No seed in LMK version 2 */
555 if (cc->key_parts == cc->tfms_count) {
556 lmk->seed = NULL;
557 return 0;
558 }
559
560 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
561 if (!lmk->seed) {
562 crypt_iv_lmk_dtr(cc);
563 ti->error = "Error kmallocing seed storage in LMK";
564 return -ENOMEM;
565 }
566
567 return 0;
568 }
569
570 static int crypt_iv_lmk_init(struct crypt_config *cc)
571 {
572 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
573 int subkey_size = cc->key_size / cc->key_parts;
574
575 /* LMK seed is on the position of LMK_KEYS + 1 key */
576 if (lmk->seed)
577 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
578 crypto_shash_digestsize(lmk->hash_tfm));
579
580 return 0;
581 }
582
583 static int crypt_iv_lmk_wipe(struct crypt_config *cc)
584 {
585 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
586
587 if (lmk->seed)
588 memset(lmk->seed, 0, LMK_SEED_SIZE);
589
590 return 0;
591 }
592
593 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
594 struct dm_crypt_request *dmreq,
595 u8 *data)
596 {
597 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
598 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
599 struct md5_state md5state;
600 __le32 buf[4];
601 int i, r;
602
603 desc->tfm = lmk->hash_tfm;
604 desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
605
606 r = crypto_shash_init(desc);
607 if (r)
608 return r;
609
610 if (lmk->seed) {
611 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
612 if (r)
613 return r;
614 }
615
616 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
617 r = crypto_shash_update(desc, data + 16, 16 * 31);
618 if (r)
619 return r;
620
621 /* Sector is cropped to 56 bits here */
622 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
623 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
624 buf[2] = cpu_to_le32(4024);
625 buf[3] = 0;
626 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
627 if (r)
628 return r;
629
630 /* No MD5 padding here */
631 r = crypto_shash_export(desc, &md5state);
632 if (r)
633 return r;
634
635 for (i = 0; i < MD5_HASH_WORDS; i++)
636 __cpu_to_le32s(&md5state.hash[i]);
637 memcpy(iv, &md5state.hash, cc->iv_size);
638
639 return 0;
640 }
641
642 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
643 struct dm_crypt_request *dmreq)
644 {
645 struct scatterlist *sg;
646 u8 *src;
647 int r = 0;
648
649 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
650 sg = crypt_get_sg_data(cc, dmreq->sg_in);
651 src = kmap_atomic(sg_page(sg));
652 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
653 kunmap_atomic(src);
654 } else
655 memset(iv, 0, cc->iv_size);
656
657 return r;
658 }
659
660 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
661 struct dm_crypt_request *dmreq)
662 {
663 struct scatterlist *sg;
664 u8 *dst;
665 int r;
666
667 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
668 return 0;
669
670 sg = crypt_get_sg_data(cc, dmreq->sg_out);
671 dst = kmap_atomic(sg_page(sg));
672 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
673
674 /* Tweak the first block of plaintext sector */
675 if (!r)
676 crypto_xor(dst + sg->offset, iv, cc->iv_size);
677
678 kunmap_atomic(dst);
679 return r;
680 }
681
682 static void crypt_iv_tcw_dtr(struct crypt_config *cc)
683 {
684 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
685
686 kzfree(tcw->iv_seed);
687 tcw->iv_seed = NULL;
688 kzfree(tcw->whitening);
689 tcw->whitening = NULL;
690
691 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
692 crypto_free_shash(tcw->crc32_tfm);
693 tcw->crc32_tfm = NULL;
694 }
695
696 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
697 const char *opts)
698 {
699 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
700
701 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
702 ti->error = "Unsupported sector size for TCW";
703 return -EINVAL;
704 }
705
706 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
707 ti->error = "Wrong key size for TCW";
708 return -EINVAL;
709 }
710
711 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0);
712 if (IS_ERR(tcw->crc32_tfm)) {
713 ti->error = "Error initializing CRC32 in TCW";
714 return PTR_ERR(tcw->crc32_tfm);
715 }
716
717 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
718 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
719 if (!tcw->iv_seed || !tcw->whitening) {
720 crypt_iv_tcw_dtr(cc);
721 ti->error = "Error allocating seed storage in TCW";
722 return -ENOMEM;
723 }
724
725 return 0;
726 }
727
728 static int crypt_iv_tcw_init(struct crypt_config *cc)
729 {
730 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
731 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
732
733 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
734 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
735 TCW_WHITENING_SIZE);
736
737 return 0;
738 }
739
740 static int crypt_iv_tcw_wipe(struct crypt_config *cc)
741 {
742 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
743
744 memset(tcw->iv_seed, 0, cc->iv_size);
745 memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
746
747 return 0;
748 }
749
750 static int crypt_iv_tcw_whitening(struct crypt_config *cc,
751 struct dm_crypt_request *dmreq,
752 u8 *data)
753 {
754 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
755 __le64 sector = cpu_to_le64(dmreq->iv_sector);
756 u8 buf[TCW_WHITENING_SIZE];
757 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
758 int i, r;
759
760 /* xor whitening with sector number */
761 crypto_xor_cpy(buf, tcw->whitening, (u8 *)&sector, 8);
762 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)&sector, 8);
763
764 /* calculate crc32 for every 32bit part and xor it */
765 desc->tfm = tcw->crc32_tfm;
766 desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP;
767 for (i = 0; i < 4; i++) {
768 r = crypto_shash_init(desc);
769 if (r)
770 goto out;
771 r = crypto_shash_update(desc, &buf[i * 4], 4);
772 if (r)
773 goto out;
774 r = crypto_shash_final(desc, &buf[i * 4]);
775 if (r)
776 goto out;
777 }
778 crypto_xor(&buf[0], &buf[12], 4);
779 crypto_xor(&buf[4], &buf[8], 4);
780
781 /* apply whitening (8 bytes) to whole sector */
782 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
783 crypto_xor(data + i * 8, buf, 8);
784 out:
785 memzero_explicit(buf, sizeof(buf));
786 return r;
787 }
788
789 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
790 struct dm_crypt_request *dmreq)
791 {
792 struct scatterlist *sg;
793 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
794 __le64 sector = cpu_to_le64(dmreq->iv_sector);
795 u8 *src;
796 int r = 0;
797
798 /* Remove whitening from ciphertext */
799 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
800 sg = crypt_get_sg_data(cc, dmreq->sg_in);
801 src = kmap_atomic(sg_page(sg));
802 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
803 kunmap_atomic(src);
804 }
805
806 /* Calculate IV */
807 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)&sector, 8);
808 if (cc->iv_size > 8)
809 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)&sector,
810 cc->iv_size - 8);
811
812 return r;
813 }
814
815 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
816 struct dm_crypt_request *dmreq)
817 {
818 struct scatterlist *sg;
819 u8 *dst;
820 int r;
821
822 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
823 return 0;
824
825 /* Apply whitening on ciphertext */
826 sg = crypt_get_sg_data(cc, dmreq->sg_out);
827 dst = kmap_atomic(sg_page(sg));
828 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
829 kunmap_atomic(dst);
830
831 return r;
832 }
833
834 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
835 struct dm_crypt_request *dmreq)
836 {
837 /* Used only for writes, there must be an additional space to store IV */
838 get_random_bytes(iv, cc->iv_size);
839 return 0;
840 }
841
842 static const struct crypt_iv_operations crypt_iv_plain_ops = {
843 .generator = crypt_iv_plain_gen
844 };
845
846 static const struct crypt_iv_operations crypt_iv_plain64_ops = {
847 .generator = crypt_iv_plain64_gen
848 };
849
850 static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
851 .generator = crypt_iv_plain64be_gen
852 };
853
854 static const struct crypt_iv_operations crypt_iv_essiv_ops = {
855 .ctr = crypt_iv_essiv_ctr,
856 .dtr = crypt_iv_essiv_dtr,
857 .init = crypt_iv_essiv_init,
858 .wipe = crypt_iv_essiv_wipe,
859 .generator = crypt_iv_essiv_gen
860 };
861
862 static const struct crypt_iv_operations crypt_iv_benbi_ops = {
863 .ctr = crypt_iv_benbi_ctr,
864 .dtr = crypt_iv_benbi_dtr,
865 .generator = crypt_iv_benbi_gen
866 };
867
868 static const struct crypt_iv_operations crypt_iv_null_ops = {
869 .generator = crypt_iv_null_gen
870 };
871
872 static const struct crypt_iv_operations crypt_iv_lmk_ops = {
873 .ctr = crypt_iv_lmk_ctr,
874 .dtr = crypt_iv_lmk_dtr,
875 .init = crypt_iv_lmk_init,
876 .wipe = crypt_iv_lmk_wipe,
877 .generator = crypt_iv_lmk_gen,
878 .post = crypt_iv_lmk_post
879 };
880
881 static const struct crypt_iv_operations crypt_iv_tcw_ops = {
882 .ctr = crypt_iv_tcw_ctr,
883 .dtr = crypt_iv_tcw_dtr,
884 .init = crypt_iv_tcw_init,
885 .wipe = crypt_iv_tcw_wipe,
886 .generator = crypt_iv_tcw_gen,
887 .post = crypt_iv_tcw_post
888 };
889
890 static struct crypt_iv_operations crypt_iv_random_ops = {
891 .generator = crypt_iv_random_gen
892 };
893
894 /*
895 * Integrity extensions
896 */
897 static bool crypt_integrity_aead(struct crypt_config *cc)
898 {
899 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
900 }
901
902 static bool crypt_integrity_hmac(struct crypt_config *cc)
903 {
904 return crypt_integrity_aead(cc) && cc->key_mac_size;
905 }
906
907 /* Get sg containing data */
908 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
909 struct scatterlist *sg)
910 {
911 if (unlikely(crypt_integrity_aead(cc)))
912 return &sg[2];
913
914 return sg;
915 }
916
917 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
918 {
919 struct bio_integrity_payload *bip;
920 unsigned int tag_len;
921 int ret;
922
923 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
924 return 0;
925
926 bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
927 if (IS_ERR(bip))
928 return PTR_ERR(bip);
929
930 tag_len = io->cc->on_disk_tag_size * bio_sectors(bio);
931
932 bip->bip_iter.bi_size = tag_len;
933 bip->bip_iter.bi_sector = io->cc->start + io->sector;
934
935 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
936 tag_len, offset_in_page(io->integrity_metadata));
937 if (unlikely(ret != tag_len))
938 return -ENOMEM;
939
940 return 0;
941 }
942
943 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
944 {
945 #ifdef CONFIG_BLK_DEV_INTEGRITY
946 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
947
948 /* From now we require underlying device with our integrity profile */
949 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
950 ti->error = "Integrity profile not supported.";
951 return -EINVAL;
952 }
953
954 if (bi->tag_size != cc->on_disk_tag_size ||
955 bi->tuple_size != cc->on_disk_tag_size) {
956 ti->error = "Integrity profile tag size mismatch.";
957 return -EINVAL;
958 }
959 if (1 << bi->interval_exp != cc->sector_size) {
960 ti->error = "Integrity profile sector size mismatch.";
961 return -EINVAL;
962 }
963
964 if (crypt_integrity_aead(cc)) {
965 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
966 DMINFO("Integrity AEAD, tag size %u, IV size %u.",
967 cc->integrity_tag_size, cc->integrity_iv_size);
968
969 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
970 ti->error = "Integrity AEAD auth tag size is not supported.";
971 return -EINVAL;
972 }
973 } else if (cc->integrity_iv_size)
974 DMINFO("Additional per-sector space %u bytes for IV.",
975 cc->integrity_iv_size);
976
977 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
978 ti->error = "Not enough space for integrity tag in the profile.";
979 return -EINVAL;
980 }
981
982 return 0;
983 #else
984 ti->error = "Integrity profile not supported.";
985 return -EINVAL;
986 #endif
987 }
988
989 static void crypt_convert_init(struct crypt_config *cc,
990 struct convert_context *ctx,
991 struct bio *bio_out, struct bio *bio_in,
992 sector_t sector)
993 {
994 ctx->bio_in = bio_in;
995 ctx->bio_out = bio_out;
996 if (bio_in)
997 ctx->iter_in = bio_in->bi_iter;
998 if (bio_out)
999 ctx->iter_out = bio_out->bi_iter;
1000 ctx->cc_sector = sector + cc->iv_offset;
1001 init_completion(&ctx->restart);
1002 }
1003
1004 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1005 void *req)
1006 {
1007 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1008 }
1009
1010 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1011 {
1012 return (void *)((char *)dmreq - cc->dmreq_start);
1013 }
1014
1015 static u8 *iv_of_dmreq(struct crypt_config *cc,
1016 struct dm_crypt_request *dmreq)
1017 {
1018 if (crypt_integrity_aead(cc))
1019 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1020 crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1021 else
1022 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1023 crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1024 }
1025
1026 static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1027 struct dm_crypt_request *dmreq)
1028 {
1029 return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1030 }
1031
1032 static uint64_t *org_sector_of_dmreq(struct crypt_config *cc,
1033 struct dm_crypt_request *dmreq)
1034 {
1035 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
1036 return (uint64_t*) ptr;
1037 }
1038
1039 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1040 struct dm_crypt_request *dmreq)
1041 {
1042 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1043 cc->iv_size + sizeof(uint64_t);
1044 return (unsigned int*)ptr;
1045 }
1046
1047 static void *tag_from_dmreq(struct crypt_config *cc,
1048 struct dm_crypt_request *dmreq)
1049 {
1050 struct convert_context *ctx = dmreq->ctx;
1051 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1052
1053 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1054 cc->on_disk_tag_size];
1055 }
1056
1057 static void *iv_tag_from_dmreq(struct crypt_config *cc,
1058 struct dm_crypt_request *dmreq)
1059 {
1060 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1061 }
1062
1063 static int crypt_convert_block_aead(struct crypt_config *cc,
1064 struct convert_context *ctx,
1065 struct aead_request *req,
1066 unsigned int tag_offset)
1067 {
1068 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1069 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1070 struct dm_crypt_request *dmreq;
1071 u8 *iv, *org_iv, *tag_iv, *tag;
1072 uint64_t *sector;
1073 int r = 0;
1074
1075 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1076
1077 /* Reject unexpected unaligned bio. */
1078 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1079 return -EIO;
1080
1081 dmreq = dmreq_of_req(cc, req);
1082 dmreq->iv_sector = ctx->cc_sector;
1083 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1084 dmreq->iv_sector >>= cc->sector_shift;
1085 dmreq->ctx = ctx;
1086
1087 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1088
1089 sector = org_sector_of_dmreq(cc, dmreq);
1090 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1091
1092 iv = iv_of_dmreq(cc, dmreq);
1093 org_iv = org_iv_of_dmreq(cc, dmreq);
1094 tag = tag_from_dmreq(cc, dmreq);
1095 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1096
1097 /* AEAD request:
1098 * |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1099 * | (authenticated) | (auth+encryption) | |
1100 * | sector_LE | IV | sector in/out | tag in/out |
1101 */
1102 sg_init_table(dmreq->sg_in, 4);
1103 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1104 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1105 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1106 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1107
1108 sg_init_table(dmreq->sg_out, 4);
1109 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1110 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1111 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1112 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1113
1114 if (cc->iv_gen_ops) {
1115 /* For READs use IV stored in integrity metadata */
1116 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1117 memcpy(org_iv, tag_iv, cc->iv_size);
1118 } else {
1119 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1120 if (r < 0)
1121 return r;
1122 /* Store generated IV in integrity metadata */
1123 if (cc->integrity_iv_size)
1124 memcpy(tag_iv, org_iv, cc->iv_size);
1125 }
1126 /* Working copy of IV, to be modified in crypto API */
1127 memcpy(iv, org_iv, cc->iv_size);
1128 }
1129
1130 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1131 if (bio_data_dir(ctx->bio_in) == WRITE) {
1132 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1133 cc->sector_size, iv);
1134 r = crypto_aead_encrypt(req);
1135 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
1136 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1137 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1138 } else {
1139 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1140 cc->sector_size + cc->integrity_tag_size, iv);
1141 r = crypto_aead_decrypt(req);
1142 }
1143
1144 if (r == -EBADMSG)
1145 DMERR_LIMIT("INTEGRITY AEAD ERROR, sector %llu",
1146 (unsigned long long)le64_to_cpu(*sector));
1147
1148 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1149 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1150
1151 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1152 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1153
1154 return r;
1155 }
1156
1157 static int crypt_convert_block_skcipher(struct crypt_config *cc,
1158 struct convert_context *ctx,
1159 struct skcipher_request *req,
1160 unsigned int tag_offset)
1161 {
1162 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1163 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1164 struct scatterlist *sg_in, *sg_out;
1165 struct dm_crypt_request *dmreq;
1166 u8 *iv, *org_iv, *tag_iv;
1167 uint64_t *sector;
1168 int r = 0;
1169
1170 /* Reject unexpected unaligned bio. */
1171 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1172 return -EIO;
1173
1174 dmreq = dmreq_of_req(cc, req);
1175 dmreq->iv_sector = ctx->cc_sector;
1176 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1177 dmreq->iv_sector >>= cc->sector_shift;
1178 dmreq->ctx = ctx;
1179
1180 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1181
1182 iv = iv_of_dmreq(cc, dmreq);
1183 org_iv = org_iv_of_dmreq(cc, dmreq);
1184 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1185
1186 sector = org_sector_of_dmreq(cc, dmreq);
1187 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1188
1189 /* For skcipher we use only the first sg item */
1190 sg_in = &dmreq->sg_in[0];
1191 sg_out = &dmreq->sg_out[0];
1192
1193 sg_init_table(sg_in, 1);
1194 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1195
1196 sg_init_table(sg_out, 1);
1197 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1198
1199 if (cc->iv_gen_ops) {
1200 /* For READs use IV stored in integrity metadata */
1201 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1202 memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1203 } else {
1204 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1205 if (r < 0)
1206 return r;
1207 /* Store generated IV in integrity metadata */
1208 if (cc->integrity_iv_size)
1209 memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1210 }
1211 /* Working copy of IV, to be modified in crypto API */
1212 memcpy(iv, org_iv, cc->iv_size);
1213 }
1214
1215 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1216
1217 if (bio_data_dir(ctx->bio_in) == WRITE)
1218 r = crypto_skcipher_encrypt(req);
1219 else
1220 r = crypto_skcipher_decrypt(req);
1221
1222 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1223 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1224
1225 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1226 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1227
1228 return r;
1229 }
1230
1231 static void kcryptd_async_done(struct crypto_async_request *async_req,
1232 int error);
1233
1234 static void crypt_alloc_req_skcipher(struct crypt_config *cc,
1235 struct convert_context *ctx)
1236 {
1237 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
1238
1239 if (!ctx->r.req)
1240 ctx->r.req = mempool_alloc(cc->req_pool, GFP_NOIO);
1241
1242 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1243
1244 /*
1245 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1246 * requests if driver request queue is full.
1247 */
1248 skcipher_request_set_callback(ctx->r.req,
1249 CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
1250 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
1251 }
1252
1253 static void crypt_alloc_req_aead(struct crypt_config *cc,
1254 struct convert_context *ctx)
1255 {
1256 if (!ctx->r.req_aead)
1257 ctx->r.req_aead = mempool_alloc(cc->req_pool, GFP_NOIO);
1258
1259 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1260
1261 /*
1262 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1263 * requests if driver request queue is full.
1264 */
1265 aead_request_set_callback(ctx->r.req_aead,
1266 CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
1267 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
1268 }
1269
1270 static void crypt_alloc_req(struct crypt_config *cc,
1271 struct convert_context *ctx)
1272 {
1273 if (crypt_integrity_aead(cc))
1274 crypt_alloc_req_aead(cc, ctx);
1275 else
1276 crypt_alloc_req_skcipher(cc, ctx);
1277 }
1278
1279 static void crypt_free_req_skcipher(struct crypt_config *cc,
1280 struct skcipher_request *req, struct bio *base_bio)
1281 {
1282 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1283
1284 if ((struct skcipher_request *)(io + 1) != req)
1285 mempool_free(req, cc->req_pool);
1286 }
1287
1288 static void crypt_free_req_aead(struct crypt_config *cc,
1289 struct aead_request *req, struct bio *base_bio)
1290 {
1291 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1292
1293 if ((struct aead_request *)(io + 1) != req)
1294 mempool_free(req, cc->req_pool);
1295 }
1296
1297 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1298 {
1299 if (crypt_integrity_aead(cc))
1300 crypt_free_req_aead(cc, req, base_bio);
1301 else
1302 crypt_free_req_skcipher(cc, req, base_bio);
1303 }
1304
1305 /*
1306 * Encrypt / decrypt data from one bio to another one (can be the same one)
1307 */
1308 static blk_status_t crypt_convert(struct crypt_config *cc,
1309 struct convert_context *ctx)
1310 {
1311 unsigned int tag_offset = 0;
1312 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1313 int r;
1314
1315 atomic_set(&ctx->cc_pending, 1);
1316
1317 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1318
1319 crypt_alloc_req(cc, ctx);
1320 atomic_inc(&ctx->cc_pending);
1321
1322 if (crypt_integrity_aead(cc))
1323 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
1324 else
1325 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
1326
1327 switch (r) {
1328 /*
1329 * The request was queued by a crypto driver
1330 * but the driver request queue is full, let's wait.
1331 */
1332 case -EBUSY:
1333 wait_for_completion(&ctx->restart);
1334 reinit_completion(&ctx->restart);
1335 /* fall through */
1336 /*
1337 * The request is queued and processed asynchronously,
1338 * completion function kcryptd_async_done() will be called.
1339 */
1340 case -EINPROGRESS:
1341 ctx->r.req = NULL;
1342 ctx->cc_sector += sector_step;
1343 tag_offset++;
1344 continue;
1345 /*
1346 * The request was already processed (synchronously).
1347 */
1348 case 0:
1349 atomic_dec(&ctx->cc_pending);
1350 ctx->cc_sector += sector_step;
1351 tag_offset++;
1352 cond_resched();
1353 continue;
1354 /*
1355 * There was a data integrity error.
1356 */
1357 case -EBADMSG:
1358 atomic_dec(&ctx->cc_pending);
1359 return BLK_STS_PROTECTION;
1360 /*
1361 * There was an error while processing the request.
1362 */
1363 default:
1364 atomic_dec(&ctx->cc_pending);
1365 return BLK_STS_IOERR;
1366 }
1367 }
1368
1369 return 0;
1370 }
1371
1372 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1373
1374 /*
1375 * Generate a new unfragmented bio with the given size
1376 * This should never violate the device limitations (but only because
1377 * max_segment_size is being constrained to PAGE_SIZE).
1378 *
1379 * This function may be called concurrently. If we allocate from the mempool
1380 * concurrently, there is a possibility of deadlock. For example, if we have
1381 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1382 * the mempool concurrently, it may deadlock in a situation where both processes
1383 * have allocated 128 pages and the mempool is exhausted.
1384 *
1385 * In order to avoid this scenario we allocate the pages under a mutex.
1386 *
1387 * In order to not degrade performance with excessive locking, we try
1388 * non-blocking allocations without a mutex first but on failure we fallback
1389 * to blocking allocations with a mutex.
1390 */
1391 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
1392 {
1393 struct crypt_config *cc = io->cc;
1394 struct bio *clone;
1395 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1396 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1397 unsigned i, len, remaining_size;
1398 struct page *page;
1399
1400 retry:
1401 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1402 mutex_lock(&cc->bio_alloc_lock);
1403
1404 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs);
1405 if (!clone)
1406 goto out;
1407
1408 clone_init(io, clone);
1409
1410 remaining_size = size;
1411
1412 for (i = 0; i < nr_iovecs; i++) {
1413 page = mempool_alloc(cc->page_pool, gfp_mask);
1414 if (!page) {
1415 crypt_free_buffer_pages(cc, clone);
1416 bio_put(clone);
1417 gfp_mask |= __GFP_DIRECT_RECLAIM;
1418 goto retry;
1419 }
1420
1421 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
1422
1423 bio_add_page(clone, page, len, 0);
1424
1425 remaining_size -= len;
1426 }
1427
1428 /* Allocate space for integrity tags */
1429 if (dm_crypt_integrity_io_alloc(io, clone)) {
1430 crypt_free_buffer_pages(cc, clone);
1431 bio_put(clone);
1432 clone = NULL;
1433 }
1434 out:
1435 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1436 mutex_unlock(&cc->bio_alloc_lock);
1437
1438 return clone;
1439 }
1440
1441 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1442 {
1443 unsigned int i;
1444 struct bio_vec *bv;
1445
1446 bio_for_each_segment_all(bv, clone, i) {
1447 BUG_ON(!bv->bv_page);
1448 mempool_free(bv->bv_page, cc->page_pool);
1449 bv->bv_page = NULL;
1450 }
1451 }
1452
1453 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1454 struct bio *bio, sector_t sector)
1455 {
1456 io->cc = cc;
1457 io->base_bio = bio;
1458 io->sector = sector;
1459 io->error = 0;
1460 io->ctx.r.req = NULL;
1461 io->integrity_metadata = NULL;
1462 io->integrity_metadata_from_pool = false;
1463 atomic_set(&io->io_pending, 0);
1464 }
1465
1466 static void crypt_inc_pending(struct dm_crypt_io *io)
1467 {
1468 atomic_inc(&io->io_pending);
1469 }
1470
1471 /*
1472 * One of the bios was finished. Check for completion of
1473 * the whole request and correctly clean up the buffer.
1474 */
1475 static void crypt_dec_pending(struct dm_crypt_io *io)
1476 {
1477 struct crypt_config *cc = io->cc;
1478 struct bio *base_bio = io->base_bio;
1479 blk_status_t error = io->error;
1480
1481 if (!atomic_dec_and_test(&io->io_pending))
1482 return;
1483
1484 if (io->ctx.r.req)
1485 crypt_free_req(cc, io->ctx.r.req, base_bio);
1486
1487 if (unlikely(io->integrity_metadata_from_pool))
1488 mempool_free(io->integrity_metadata, io->cc->tag_pool);
1489 else
1490 kfree(io->integrity_metadata);
1491
1492 base_bio->bi_status = error;
1493 bio_endio(base_bio);
1494 }
1495
1496 /*
1497 * kcryptd/kcryptd_io:
1498 *
1499 * Needed because it would be very unwise to do decryption in an
1500 * interrupt context.
1501 *
1502 * kcryptd performs the actual encryption or decryption.
1503 *
1504 * kcryptd_io performs the IO submission.
1505 *
1506 * They must be separated as otherwise the final stages could be
1507 * starved by new requests which can block in the first stages due
1508 * to memory allocation.
1509 *
1510 * The work is done per CPU global for all dm-crypt instances.
1511 * They should not depend on each other and do not block.
1512 */
1513 static void crypt_endio(struct bio *clone)
1514 {
1515 struct dm_crypt_io *io = clone->bi_private;
1516 struct crypt_config *cc = io->cc;
1517 unsigned rw = bio_data_dir(clone);
1518 blk_status_t error;
1519
1520 /*
1521 * free the processed pages
1522 */
1523 if (rw == WRITE)
1524 crypt_free_buffer_pages(cc, clone);
1525
1526 error = clone->bi_status;
1527 bio_put(clone);
1528
1529 if (rw == READ && !error) {
1530 kcryptd_queue_crypt(io);
1531 return;
1532 }
1533
1534 if (unlikely(error))
1535 io->error = error;
1536
1537 crypt_dec_pending(io);
1538 }
1539
1540 static void clone_init(struct dm_crypt_io *io, struct bio *clone)
1541 {
1542 struct crypt_config *cc = io->cc;
1543
1544 clone->bi_private = io;
1545 clone->bi_end_io = crypt_endio;
1546 bio_set_dev(clone, cc->dev->bdev);
1547 clone->bi_opf = io->base_bio->bi_opf;
1548 }
1549
1550 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1551 {
1552 struct crypt_config *cc = io->cc;
1553 struct bio *clone;
1554
1555 /*
1556 * We need the original biovec array in order to decrypt
1557 * the whole bio data *afterwards* -- thanks to immutable
1558 * biovecs we don't need to worry about the block layer
1559 * modifying the biovec array; so leverage bio_clone_fast().
1560 */
1561 clone = bio_clone_fast(io->base_bio, gfp, cc->bs);
1562 if (!clone)
1563 return 1;
1564
1565 crypt_inc_pending(io);
1566
1567 clone_init(io, clone);
1568 clone->bi_iter.bi_sector = cc->start + io->sector;
1569
1570 if (dm_crypt_integrity_io_alloc(io, clone)) {
1571 crypt_dec_pending(io);
1572 bio_put(clone);
1573 return 1;
1574 }
1575
1576 generic_make_request(clone);
1577 return 0;
1578 }
1579
1580 static void kcryptd_io_read_work(struct work_struct *work)
1581 {
1582 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1583
1584 crypt_inc_pending(io);
1585 if (kcryptd_io_read(io, GFP_NOIO))
1586 io->error = BLK_STS_RESOURCE;
1587 crypt_dec_pending(io);
1588 }
1589
1590 static void kcryptd_queue_read(struct dm_crypt_io *io)
1591 {
1592 struct crypt_config *cc = io->cc;
1593
1594 INIT_WORK(&io->work, kcryptd_io_read_work);
1595 queue_work(cc->io_queue, &io->work);
1596 }
1597
1598 static void kcryptd_io_write(struct dm_crypt_io *io)
1599 {
1600 struct bio *clone = io->ctx.bio_out;
1601
1602 generic_make_request(clone);
1603 }
1604
1605 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1606
1607 static int dmcrypt_write(void *data)
1608 {
1609 struct crypt_config *cc = data;
1610 struct dm_crypt_io *io;
1611
1612 while (1) {
1613 struct rb_root write_tree;
1614 struct blk_plug plug;
1615
1616 DECLARE_WAITQUEUE(wait, current);
1617
1618 spin_lock_irq(&cc->write_thread_wait.lock);
1619 continue_locked:
1620
1621 if (!RB_EMPTY_ROOT(&cc->write_tree))
1622 goto pop_from_list;
1623
1624 set_current_state(TASK_INTERRUPTIBLE);
1625 __add_wait_queue(&cc->write_thread_wait, &wait);
1626
1627 spin_unlock_irq(&cc->write_thread_wait.lock);
1628
1629 if (unlikely(kthread_should_stop())) {
1630 set_current_state(TASK_RUNNING);
1631 remove_wait_queue(&cc->write_thread_wait, &wait);
1632 break;
1633 }
1634
1635 schedule();
1636
1637 set_current_state(TASK_RUNNING);
1638 spin_lock_irq(&cc->write_thread_wait.lock);
1639 __remove_wait_queue(&cc->write_thread_wait, &wait);
1640 goto continue_locked;
1641
1642 pop_from_list:
1643 write_tree = cc->write_tree;
1644 cc->write_tree = RB_ROOT;
1645 spin_unlock_irq(&cc->write_thread_wait.lock);
1646
1647 BUG_ON(rb_parent(write_tree.rb_node));
1648
1649 /*
1650 * Note: we cannot walk the tree here with rb_next because
1651 * the structures may be freed when kcryptd_io_write is called.
1652 */
1653 blk_start_plug(&plug);
1654 do {
1655 io = crypt_io_from_node(rb_first(&write_tree));
1656 rb_erase(&io->rb_node, &write_tree);
1657 kcryptd_io_write(io);
1658 } while (!RB_EMPTY_ROOT(&write_tree));
1659 blk_finish_plug(&plug);
1660 }
1661 return 0;
1662 }
1663
1664 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1665 {
1666 struct bio *clone = io->ctx.bio_out;
1667 struct crypt_config *cc = io->cc;
1668 unsigned long flags;
1669 sector_t sector;
1670 struct rb_node **rbp, *parent;
1671
1672 if (unlikely(io->error)) {
1673 crypt_free_buffer_pages(cc, clone);
1674 bio_put(clone);
1675 crypt_dec_pending(io);
1676 return;
1677 }
1678
1679 /* crypt_convert should have filled the clone bio */
1680 BUG_ON(io->ctx.iter_out.bi_size);
1681
1682 clone->bi_iter.bi_sector = cc->start + io->sector;
1683
1684 if (likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) {
1685 generic_make_request(clone);
1686 return;
1687 }
1688
1689 spin_lock_irqsave(&cc->write_thread_wait.lock, flags);
1690 rbp = &cc->write_tree.rb_node;
1691 parent = NULL;
1692 sector = io->sector;
1693 while (*rbp) {
1694 parent = *rbp;
1695 if (sector < crypt_io_from_node(parent)->sector)
1696 rbp = &(*rbp)->rb_left;
1697 else
1698 rbp = &(*rbp)->rb_right;
1699 }
1700 rb_link_node(&io->rb_node, parent, rbp);
1701 rb_insert_color(&io->rb_node, &cc->write_tree);
1702
1703 wake_up_locked(&cc->write_thread_wait);
1704 spin_unlock_irqrestore(&cc->write_thread_wait.lock, flags);
1705 }
1706
1707 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
1708 {
1709 struct crypt_config *cc = io->cc;
1710 struct bio *clone;
1711 int crypt_finished;
1712 sector_t sector = io->sector;
1713 blk_status_t r;
1714
1715 /*
1716 * Prevent io from disappearing until this function completes.
1717 */
1718 crypt_inc_pending(io);
1719 crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
1720
1721 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1722 if (unlikely(!clone)) {
1723 io->error = BLK_STS_IOERR;
1724 goto dec;
1725 }
1726
1727 io->ctx.bio_out = clone;
1728 io->ctx.iter_out = clone->bi_iter;
1729
1730 sector += bio_sectors(clone);
1731
1732 crypt_inc_pending(io);
1733 r = crypt_convert(cc, &io->ctx);
1734 if (r)
1735 io->error = r;
1736 crypt_finished = atomic_dec_and_test(&io->ctx.cc_pending);
1737
1738 /* Encryption was already finished, submit io now */
1739 if (crypt_finished) {
1740 kcryptd_crypt_write_io_submit(io, 0);
1741 io->sector = sector;
1742 }
1743
1744 dec:
1745 crypt_dec_pending(io);
1746 }
1747
1748 static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
1749 {
1750 crypt_dec_pending(io);
1751 }
1752
1753 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
1754 {
1755 struct crypt_config *cc = io->cc;
1756 blk_status_t r;
1757
1758 crypt_inc_pending(io);
1759
1760 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
1761 io->sector);
1762
1763 r = crypt_convert(cc, &io->ctx);
1764 if (r)
1765 io->error = r;
1766
1767 if (atomic_dec_and_test(&io->ctx.cc_pending))
1768 kcryptd_crypt_read_done(io);
1769
1770 crypt_dec_pending(io);
1771 }
1772
1773 static void kcryptd_async_done(struct crypto_async_request *async_req,
1774 int error)
1775 {
1776 struct dm_crypt_request *dmreq = async_req->data;
1777 struct convert_context *ctx = dmreq->ctx;
1778 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1779 struct crypt_config *cc = io->cc;
1780
1781 /*
1782 * A request from crypto driver backlog is going to be processed now,
1783 * finish the completion and continue in crypt_convert().
1784 * (Callback will be called for the second time for this request.)
1785 */
1786 if (error == -EINPROGRESS) {
1787 complete(&ctx->restart);
1788 return;
1789 }
1790
1791 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
1792 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
1793
1794 if (error == -EBADMSG) {
1795 DMERR_LIMIT("INTEGRITY AEAD ERROR, sector %llu",
1796 (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)));
1797 io->error = BLK_STS_PROTECTION;
1798 } else if (error < 0)
1799 io->error = BLK_STS_IOERR;
1800
1801 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
1802
1803 if (!atomic_dec_and_test(&ctx->cc_pending))
1804 return;
1805
1806 if (bio_data_dir(io->base_bio) == READ)
1807 kcryptd_crypt_read_done(io);
1808 else
1809 kcryptd_crypt_write_io_submit(io, 1);
1810 }
1811
1812 static void kcryptd_crypt(struct work_struct *work)
1813 {
1814 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1815
1816 if (bio_data_dir(io->base_bio) == READ)
1817 kcryptd_crypt_read_convert(io);
1818 else
1819 kcryptd_crypt_write_convert(io);
1820 }
1821
1822 static void kcryptd_queue_crypt(struct dm_crypt_io *io)
1823 {
1824 struct crypt_config *cc = io->cc;
1825
1826 INIT_WORK(&io->work, kcryptd_crypt);
1827 queue_work(cc->crypt_queue, &io->work);
1828 }
1829
1830 static void crypt_free_tfms_aead(struct crypt_config *cc)
1831 {
1832 if (!cc->cipher_tfm.tfms_aead)
1833 return;
1834
1835 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
1836 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
1837 cc->cipher_tfm.tfms_aead[0] = NULL;
1838 }
1839
1840 kfree(cc->cipher_tfm.tfms_aead);
1841 cc->cipher_tfm.tfms_aead = NULL;
1842 }
1843
1844 static void crypt_free_tfms_skcipher(struct crypt_config *cc)
1845 {
1846 unsigned i;
1847
1848 if (!cc->cipher_tfm.tfms)
1849 return;
1850
1851 for (i = 0; i < cc->tfms_count; i++)
1852 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
1853 crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
1854 cc->cipher_tfm.tfms[i] = NULL;
1855 }
1856
1857 kfree(cc->cipher_tfm.tfms);
1858 cc->cipher_tfm.tfms = NULL;
1859 }
1860
1861 static void crypt_free_tfms(struct crypt_config *cc)
1862 {
1863 if (crypt_integrity_aead(cc))
1864 crypt_free_tfms_aead(cc);
1865 else
1866 crypt_free_tfms_skcipher(cc);
1867 }
1868
1869 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
1870 {
1871 unsigned i;
1872 int err;
1873
1874 cc->cipher_tfm.tfms = kzalloc(cc->tfms_count *
1875 sizeof(struct crypto_skcipher *), GFP_KERNEL);
1876 if (!cc->cipher_tfm.tfms)
1877 return -ENOMEM;
1878
1879 for (i = 0; i < cc->tfms_count; i++) {
1880 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 0);
1881 if (IS_ERR(cc->cipher_tfm.tfms[i])) {
1882 err = PTR_ERR(cc->cipher_tfm.tfms[i]);
1883 crypt_free_tfms(cc);
1884 return err;
1885 }
1886 }
1887
1888 return 0;
1889 }
1890
1891 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
1892 {
1893 int err;
1894
1895 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
1896 if (!cc->cipher_tfm.tfms)
1897 return -ENOMEM;
1898
1899 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 0);
1900 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
1901 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
1902 crypt_free_tfms(cc);
1903 return err;
1904 }
1905
1906 return 0;
1907 }
1908
1909 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
1910 {
1911 if (crypt_integrity_aead(cc))
1912 return crypt_alloc_tfms_aead(cc, ciphermode);
1913 else
1914 return crypt_alloc_tfms_skcipher(cc, ciphermode);
1915 }
1916
1917 static unsigned crypt_subkey_size(struct crypt_config *cc)
1918 {
1919 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
1920 }
1921
1922 static unsigned crypt_authenckey_size(struct crypt_config *cc)
1923 {
1924 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
1925 }
1926
1927 /*
1928 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
1929 * the key must be for some reason in special format.
1930 * This funcion converts cc->key to this special format.
1931 */
1932 static void crypt_copy_authenckey(char *p, const void *key,
1933 unsigned enckeylen, unsigned authkeylen)
1934 {
1935 struct crypto_authenc_key_param *param;
1936 struct rtattr *rta;
1937
1938 rta = (struct rtattr *)p;
1939 param = RTA_DATA(rta);
1940 param->enckeylen = cpu_to_be32(enckeylen);
1941 rta->rta_len = RTA_LENGTH(sizeof(*param));
1942 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
1943 p += RTA_SPACE(sizeof(*param));
1944 memcpy(p, key + enckeylen, authkeylen);
1945 p += authkeylen;
1946 memcpy(p, key, enckeylen);
1947 }
1948
1949 static int crypt_setkey(struct crypt_config *cc)
1950 {
1951 unsigned subkey_size;
1952 int err = 0, i, r;
1953
1954 /* Ignore extra keys (which are used for IV etc) */
1955 subkey_size = crypt_subkey_size(cc);
1956
1957 if (crypt_integrity_hmac(cc))
1958 crypt_copy_authenckey(cc->authenc_key, cc->key,
1959 subkey_size - cc->key_mac_size,
1960 cc->key_mac_size);
1961 for (i = 0; i < cc->tfms_count; i++) {
1962 if (crypt_integrity_hmac(cc))
1963 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
1964 cc->authenc_key, crypt_authenckey_size(cc));
1965 else if (crypt_integrity_aead(cc))
1966 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
1967 cc->key + (i * subkey_size),
1968 subkey_size);
1969 else
1970 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
1971 cc->key + (i * subkey_size),
1972 subkey_size);
1973 if (r)
1974 err = r;
1975 }
1976
1977 if (crypt_integrity_hmac(cc))
1978 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
1979
1980 return err;
1981 }
1982
1983 #ifdef CONFIG_KEYS
1984
1985 static bool contains_whitespace(const char *str)
1986 {
1987 while (*str)
1988 if (isspace(*str++))
1989 return true;
1990 return false;
1991 }
1992
1993 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
1994 {
1995 char *new_key_string, *key_desc;
1996 int ret;
1997 struct key *key;
1998 const struct user_key_payload *ukp;
1999
2000 /*
2001 * Reject key_string with whitespace. dm core currently lacks code for
2002 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2003 */
2004 if (contains_whitespace(key_string)) {
2005 DMERR("whitespace chars not allowed in key string");
2006 return -EINVAL;
2007 }
2008
2009 /* look for next ':' separating key_type from key_description */
2010 key_desc = strpbrk(key_string, ":");
2011 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2012 return -EINVAL;
2013
2014 if (strncmp(key_string, "logon:", key_desc - key_string + 1) &&
2015 strncmp(key_string, "user:", key_desc - key_string + 1))
2016 return -EINVAL;
2017
2018 new_key_string = kstrdup(key_string, GFP_KERNEL);
2019 if (!new_key_string)
2020 return -ENOMEM;
2021
2022 key = request_key(key_string[0] == 'l' ? &key_type_logon : &key_type_user,
2023 key_desc + 1, NULL);
2024 if (IS_ERR(key)) {
2025 kzfree(new_key_string);
2026 return PTR_ERR(key);
2027 }
2028
2029 down_read(&key->sem);
2030
2031 ukp = user_key_payload_locked(key);
2032 if (!ukp) {
2033 up_read(&key->sem);
2034 key_put(key);
2035 kzfree(new_key_string);
2036 return -EKEYREVOKED;
2037 }
2038
2039 if (cc->key_size != ukp->datalen) {
2040 up_read(&key->sem);
2041 key_put(key);
2042 kzfree(new_key_string);
2043 return -EINVAL;
2044 }
2045
2046 memcpy(cc->key, ukp->data, cc->key_size);
2047
2048 up_read(&key->sem);
2049 key_put(key);
2050
2051 /* clear the flag since following operations may invalidate previously valid key */
2052 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2053
2054 ret = crypt_setkey(cc);
2055
2056 /* wipe the kernel key payload copy in each case */
2057 memset(cc->key, 0, cc->key_size * sizeof(u8));
2058
2059 if (!ret) {
2060 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2061 kzfree(cc->key_string);
2062 cc->key_string = new_key_string;
2063 } else
2064 kzfree(new_key_string);
2065
2066 return ret;
2067 }
2068
2069 static int get_key_size(char **key_string)
2070 {
2071 char *colon, dummy;
2072 int ret;
2073
2074 if (*key_string[0] != ':')
2075 return strlen(*key_string) >> 1;
2076
2077 /* look for next ':' in key string */
2078 colon = strpbrk(*key_string + 1, ":");
2079 if (!colon)
2080 return -EINVAL;
2081
2082 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2083 return -EINVAL;
2084
2085 *key_string = colon;
2086
2087 /* remaining key string should be :<logon|user>:<key_desc> */
2088
2089 return ret;
2090 }
2091
2092 #else
2093
2094 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2095 {
2096 return -EINVAL;
2097 }
2098
2099 static int get_key_size(char **key_string)
2100 {
2101 return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1;
2102 }
2103
2104 #endif
2105
2106 static int crypt_set_key(struct crypt_config *cc, char *key)
2107 {
2108 int r = -EINVAL;
2109 int key_string_len = strlen(key);
2110
2111 /* Hyphen (which gives a key_size of zero) means there is no key. */
2112 if (!cc->key_size && strcmp(key, "-"))
2113 goto out;
2114
2115 /* ':' means the key is in kernel keyring, short-circuit normal key processing */
2116 if (key[0] == ':') {
2117 r = crypt_set_keyring_key(cc, key + 1);
2118 goto out;
2119 }
2120
2121 /* clear the flag since following operations may invalidate previously valid key */
2122 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2123
2124 /* wipe references to any kernel keyring key */
2125 kzfree(cc->key_string);
2126 cc->key_string = NULL;
2127
2128 /* Decode key from its hex representation. */
2129 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2130 goto out;
2131
2132 r = crypt_setkey(cc);
2133 if (!r)
2134 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2135
2136 out:
2137 /* Hex key string not needed after here, so wipe it. */
2138 memset(key, '0', key_string_len);
2139
2140 return r;
2141 }
2142
2143 static int crypt_wipe_key(struct crypt_config *cc)
2144 {
2145 int r;
2146
2147 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2148 get_random_bytes(&cc->key, cc->key_size);
2149 kzfree(cc->key_string);
2150 cc->key_string = NULL;
2151 r = crypt_setkey(cc);
2152 memset(&cc->key, 0, cc->key_size * sizeof(u8));
2153
2154 return r;
2155 }
2156
2157 static void crypt_dtr(struct dm_target *ti)
2158 {
2159 struct crypt_config *cc = ti->private;
2160
2161 ti->private = NULL;
2162
2163 if (!cc)
2164 return;
2165
2166 if (cc->write_thread)
2167 kthread_stop(cc->write_thread);
2168
2169 if (cc->io_queue)
2170 destroy_workqueue(cc->io_queue);
2171 if (cc->crypt_queue)
2172 destroy_workqueue(cc->crypt_queue);
2173
2174 crypt_free_tfms(cc);
2175
2176 if (cc->bs)
2177 bioset_free(cc->bs);
2178
2179 mempool_destroy(cc->page_pool);
2180 mempool_destroy(cc->req_pool);
2181 mempool_destroy(cc->tag_pool);
2182
2183 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2184 cc->iv_gen_ops->dtr(cc);
2185
2186 if (cc->dev)
2187 dm_put_device(ti, cc->dev);
2188
2189 kzfree(cc->cipher);
2190 kzfree(cc->cipher_string);
2191 kzfree(cc->key_string);
2192 kzfree(cc->cipher_auth);
2193 kzfree(cc->authenc_key);
2194
2195 /* Must zero key material before freeing */
2196 kzfree(cc);
2197 }
2198
2199 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2200 {
2201 struct crypt_config *cc = ti->private;
2202
2203 if (crypt_integrity_aead(cc))
2204 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2205 else
2206 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2207
2208 if (cc->iv_size)
2209 /* at least a 64 bit sector number should fit in our buffer */
2210 cc->iv_size = max(cc->iv_size,
2211 (unsigned int)(sizeof(u64) / sizeof(u8)));
2212 else if (ivmode) {
2213 DMWARN("Selected cipher does not support IVs");
2214 ivmode = NULL;
2215 }
2216
2217 /* Choose ivmode, see comments at iv code. */
2218 if (ivmode == NULL)
2219 cc->iv_gen_ops = NULL;
2220 else if (strcmp(ivmode, "plain") == 0)
2221 cc->iv_gen_ops = &crypt_iv_plain_ops;
2222 else if (strcmp(ivmode, "plain64") == 0)
2223 cc->iv_gen_ops = &crypt_iv_plain64_ops;
2224 else if (strcmp(ivmode, "plain64be") == 0)
2225 cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2226 else if (strcmp(ivmode, "essiv") == 0)
2227 cc->iv_gen_ops = &crypt_iv_essiv_ops;
2228 else if (strcmp(ivmode, "benbi") == 0)
2229 cc->iv_gen_ops = &crypt_iv_benbi_ops;
2230 else if (strcmp(ivmode, "null") == 0)
2231 cc->iv_gen_ops = &crypt_iv_null_ops;
2232 else if (strcmp(ivmode, "lmk") == 0) {
2233 cc->iv_gen_ops = &crypt_iv_lmk_ops;
2234 /*
2235 * Version 2 and 3 is recognised according
2236 * to length of provided multi-key string.
2237 * If present (version 3), last key is used as IV seed.
2238 * All keys (including IV seed) are always the same size.
2239 */
2240 if (cc->key_size % cc->key_parts) {
2241 cc->key_parts++;
2242 cc->key_extra_size = cc->key_size / cc->key_parts;
2243 }
2244 } else if (strcmp(ivmode, "tcw") == 0) {
2245 cc->iv_gen_ops = &crypt_iv_tcw_ops;
2246 cc->key_parts += 2; /* IV + whitening */
2247 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2248 } else if (strcmp(ivmode, "random") == 0) {
2249 cc->iv_gen_ops = &crypt_iv_random_ops;
2250 /* Need storage space in integrity fields. */
2251 cc->integrity_iv_size = cc->iv_size;
2252 } else {
2253 ti->error = "Invalid IV mode";
2254 return -EINVAL;
2255 }
2256
2257 return 0;
2258 }
2259
2260 /*
2261 * Workaround to parse cipher algorithm from crypto API spec.
2262 * The cc->cipher is currently used only in ESSIV.
2263 * This should be probably done by crypto-api calls (once available...)
2264 */
2265 static int crypt_ctr_blkdev_cipher(struct crypt_config *cc)
2266 {
2267 const char *alg_name = NULL;
2268 char *start, *end;
2269
2270 if (crypt_integrity_aead(cc)) {
2271 alg_name = crypto_tfm_alg_name(crypto_aead_tfm(any_tfm_aead(cc)));
2272 if (!alg_name)
2273 return -EINVAL;
2274 if (crypt_integrity_hmac(cc)) {
2275 alg_name = strchr(alg_name, ',');
2276 if (!alg_name)
2277 return -EINVAL;
2278 }
2279 alg_name++;
2280 } else {
2281 alg_name = crypto_tfm_alg_name(crypto_skcipher_tfm(any_tfm(cc)));
2282 if (!alg_name)
2283 return -EINVAL;
2284 }
2285
2286 start = strchr(alg_name, '(');
2287 end = strchr(alg_name, ')');
2288
2289 if (!start && !end) {
2290 cc->cipher = kstrdup(alg_name, GFP_KERNEL);
2291 return cc->cipher ? 0 : -ENOMEM;
2292 }
2293
2294 if (!start || !end || ++start >= end)
2295 return -EINVAL;
2296
2297 cc->cipher = kzalloc(end - start + 1, GFP_KERNEL);
2298 if (!cc->cipher)
2299 return -ENOMEM;
2300
2301 strncpy(cc->cipher, start, end - start);
2302
2303 return 0;
2304 }
2305
2306 /*
2307 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2308 * The HMAC is needed to calculate tag size (HMAC digest size).
2309 * This should be probably done by crypto-api calls (once available...)
2310 */
2311 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2312 {
2313 char *start, *end, *mac_alg = NULL;
2314 struct crypto_ahash *mac;
2315
2316 if (!strstarts(cipher_api, "authenc("))
2317 return 0;
2318
2319 start = strchr(cipher_api, '(');
2320 end = strchr(cipher_api, ',');
2321 if (!start || !end || ++start > end)
2322 return -EINVAL;
2323
2324 mac_alg = kzalloc(end - start + 1, GFP_KERNEL);
2325 if (!mac_alg)
2326 return -ENOMEM;
2327 strncpy(mac_alg, start, end - start);
2328
2329 mac = crypto_alloc_ahash(mac_alg, 0, 0);
2330 kfree(mac_alg);
2331
2332 if (IS_ERR(mac))
2333 return PTR_ERR(mac);
2334
2335 cc->key_mac_size = crypto_ahash_digestsize(mac);
2336 crypto_free_ahash(mac);
2337
2338 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2339 if (!cc->authenc_key)
2340 return -ENOMEM;
2341
2342 return 0;
2343 }
2344
2345 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2346 char **ivmode, char **ivopts)
2347 {
2348 struct crypt_config *cc = ti->private;
2349 char *tmp, *cipher_api;
2350 int ret = -EINVAL;
2351
2352 cc->tfms_count = 1;
2353
2354 /*
2355 * New format (capi: prefix)
2356 * capi:cipher_api_spec-iv:ivopts
2357 */
2358 tmp = &cipher_in[strlen("capi:")];
2359 cipher_api = strsep(&tmp, "-");
2360 *ivmode = strsep(&tmp, ":");
2361 *ivopts = tmp;
2362
2363 if (*ivmode && !strcmp(*ivmode, "lmk"))
2364 cc->tfms_count = 64;
2365
2366 cc->key_parts = cc->tfms_count;
2367
2368 /* Allocate cipher */
2369 ret = crypt_alloc_tfms(cc, cipher_api);
2370 if (ret < 0) {
2371 ti->error = "Error allocating crypto tfm";
2372 return ret;
2373 }
2374
2375 /* Alloc AEAD, can be used only in new format. */
2376 if (crypt_integrity_aead(cc)) {
2377 ret = crypt_ctr_auth_cipher(cc, cipher_api);
2378 if (ret < 0) {
2379 ti->error = "Invalid AEAD cipher spec";
2380 return -ENOMEM;
2381 }
2382 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2383 } else
2384 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2385
2386 ret = crypt_ctr_blkdev_cipher(cc);
2387 if (ret < 0) {
2388 ti->error = "Cannot allocate cipher string";
2389 return -ENOMEM;
2390 }
2391
2392 return 0;
2393 }
2394
2395 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2396 char **ivmode, char **ivopts)
2397 {
2398 struct crypt_config *cc = ti->private;
2399 char *tmp, *cipher, *chainmode, *keycount;
2400 char *cipher_api = NULL;
2401 int ret = -EINVAL;
2402 char dummy;
2403
2404 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2405 ti->error = "Bad cipher specification";
2406 return -EINVAL;
2407 }
2408
2409 /*
2410 * Legacy dm-crypt cipher specification
2411 * cipher[:keycount]-mode-iv:ivopts
2412 */
2413 tmp = cipher_in;
2414 keycount = strsep(&tmp, "-");
2415 cipher = strsep(&keycount, ":");
2416
2417 if (!keycount)
2418 cc->tfms_count = 1;
2419 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
2420 !is_power_of_2(cc->tfms_count)) {
2421 ti->error = "Bad cipher key count specification";
2422 return -EINVAL;
2423 }
2424 cc->key_parts = cc->tfms_count;
2425
2426 cc->cipher = kstrdup(cipher, GFP_KERNEL);
2427 if (!cc->cipher)
2428 goto bad_mem;
2429
2430 chainmode = strsep(&tmp, "-");
2431 *ivopts = strsep(&tmp, "-");
2432 *ivmode = strsep(&*ivopts, ":");
2433
2434 if (tmp)
2435 DMWARN("Ignoring unexpected additional cipher options");
2436
2437 /*
2438 * For compatibility with the original dm-crypt mapping format, if
2439 * only the cipher name is supplied, use cbc-plain.
2440 */
2441 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
2442 chainmode = "cbc";
2443 *ivmode = "plain";
2444 }
2445
2446 if (strcmp(chainmode, "ecb") && !*ivmode) {
2447 ti->error = "IV mechanism required";
2448 return -EINVAL;
2449 }
2450
2451 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
2452 if (!cipher_api)
2453 goto bad_mem;
2454
2455 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2456 "%s(%s)", chainmode, cipher);
2457 if (ret < 0) {
2458 kfree(cipher_api);
2459 goto bad_mem;
2460 }
2461
2462 /* Allocate cipher */
2463 ret = crypt_alloc_tfms(cc, cipher_api);
2464 if (ret < 0) {
2465 ti->error = "Error allocating crypto tfm";
2466 kfree(cipher_api);
2467 return ret;
2468 }
2469 kfree(cipher_api);
2470
2471 return 0;
2472 bad_mem:
2473 ti->error = "Cannot allocate cipher strings";
2474 return -ENOMEM;
2475 }
2476
2477 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
2478 {
2479 struct crypt_config *cc = ti->private;
2480 char *ivmode = NULL, *ivopts = NULL;
2481 int ret;
2482
2483 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
2484 if (!cc->cipher_string) {
2485 ti->error = "Cannot allocate cipher strings";
2486 return -ENOMEM;
2487 }
2488
2489 if (strstarts(cipher_in, "capi:"))
2490 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
2491 else
2492 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
2493 if (ret)
2494 return ret;
2495
2496 /* Initialize IV */
2497 ret = crypt_ctr_ivmode(ti, ivmode);
2498 if (ret < 0)
2499 return ret;
2500
2501 /* Initialize and set key */
2502 ret = crypt_set_key(cc, key);
2503 if (ret < 0) {
2504 ti->error = "Error decoding and setting key";
2505 return ret;
2506 }
2507
2508 /* Allocate IV */
2509 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
2510 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
2511 if (ret < 0) {
2512 ti->error = "Error creating IV";
2513 return ret;
2514 }
2515 }
2516
2517 /* Initialize IV (set keys for ESSIV etc) */
2518 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
2519 ret = cc->iv_gen_ops->init(cc);
2520 if (ret < 0) {
2521 ti->error = "Error initialising IV";
2522 return ret;
2523 }
2524 }
2525
2526 return ret;
2527 }
2528
2529 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
2530 {
2531 struct crypt_config *cc = ti->private;
2532 struct dm_arg_set as;
2533 static const struct dm_arg _args[] = {
2534 {0, 6, "Invalid number of feature args"},
2535 };
2536 unsigned int opt_params, val;
2537 const char *opt_string, *sval;
2538 char dummy;
2539 int ret;
2540
2541 /* Optional parameters */
2542 as.argc = argc;
2543 as.argv = argv;
2544
2545 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
2546 if (ret)
2547 return ret;
2548
2549 while (opt_params--) {
2550 opt_string = dm_shift_arg(&as);
2551 if (!opt_string) {
2552 ti->error = "Not enough feature arguments";
2553 return -EINVAL;
2554 }
2555
2556 if (!strcasecmp(opt_string, "allow_discards"))
2557 ti->num_discard_bios = 1;
2558
2559 else if (!strcasecmp(opt_string, "same_cpu_crypt"))
2560 set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
2561
2562 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
2563 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
2564 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
2565 if (val == 0 || val > MAX_TAG_SIZE) {
2566 ti->error = "Invalid integrity arguments";
2567 return -EINVAL;
2568 }
2569 cc->on_disk_tag_size = val;
2570 sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
2571 if (!strcasecmp(sval, "aead")) {
2572 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
2573 } else if (strcasecmp(sval, "none")) {
2574 ti->error = "Unknown integrity profile";
2575 return -EINVAL;
2576 }
2577
2578 cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
2579 if (!cc->cipher_auth)
2580 return -ENOMEM;
2581 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
2582 if (cc->sector_size < (1 << SECTOR_SHIFT) ||
2583 cc->sector_size > 4096 ||
2584 (cc->sector_size & (cc->sector_size - 1))) {
2585 ti->error = "Invalid feature value for sector_size";
2586 return -EINVAL;
2587 }
2588 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
2589 ti->error = "Device size is not multiple of sector_size feature";
2590 return -EINVAL;
2591 }
2592 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
2593 } else if (!strcasecmp(opt_string, "iv_large_sectors"))
2594 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
2595 else {
2596 ti->error = "Invalid feature arguments";
2597 return -EINVAL;
2598 }
2599 }
2600
2601 return 0;
2602 }
2603
2604 /*
2605 * Construct an encryption mapping:
2606 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
2607 */
2608 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2609 {
2610 struct crypt_config *cc;
2611 int key_size;
2612 unsigned int align_mask;
2613 unsigned long long tmpll;
2614 int ret;
2615 size_t iv_size_padding, additional_req_size;
2616 char dummy;
2617
2618 if (argc < 5) {
2619 ti->error = "Not enough arguments";
2620 return -EINVAL;
2621 }
2622
2623 key_size = get_key_size(&argv[1]);
2624 if (key_size < 0) {
2625 ti->error = "Cannot parse key size";
2626 return -EINVAL;
2627 }
2628
2629 cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);
2630 if (!cc) {
2631 ti->error = "Cannot allocate encryption context";
2632 return -ENOMEM;
2633 }
2634 cc->key_size = key_size;
2635 cc->sector_size = (1 << SECTOR_SHIFT);
2636 cc->sector_shift = 0;
2637
2638 ti->private = cc;
2639
2640 /* Optional parameters need to be read before cipher constructor */
2641 if (argc > 5) {
2642 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
2643 if (ret)
2644 goto bad;
2645 }
2646
2647 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
2648 if (ret < 0)
2649 goto bad;
2650
2651 if (crypt_integrity_aead(cc)) {
2652 cc->dmreq_start = sizeof(struct aead_request);
2653 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
2654 align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
2655 } else {
2656 cc->dmreq_start = sizeof(struct skcipher_request);
2657 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
2658 align_mask = crypto_skcipher_alignmask(any_tfm(cc));
2659 }
2660 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
2661
2662 if (align_mask < CRYPTO_MINALIGN) {
2663 /* Allocate the padding exactly */
2664 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
2665 & align_mask;
2666 } else {
2667 /*
2668 * If the cipher requires greater alignment than kmalloc
2669 * alignment, we don't know the exact position of the
2670 * initialization vector. We must assume worst case.
2671 */
2672 iv_size_padding = align_mask;
2673 }
2674
2675 ret = -ENOMEM;
2676
2677 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */
2678 additional_req_size = sizeof(struct dm_crypt_request) +
2679 iv_size_padding + cc->iv_size +
2680 cc->iv_size +
2681 sizeof(uint64_t) +
2682 sizeof(unsigned int);
2683
2684 cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + additional_req_size);
2685 if (!cc->req_pool) {
2686 ti->error = "Cannot allocate crypt request mempool";
2687 goto bad;
2688 }
2689
2690 cc->per_bio_data_size = ti->per_io_data_size =
2691 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
2692 ARCH_KMALLOC_MINALIGN);
2693
2694 cc->page_pool = mempool_create_page_pool(BIO_MAX_PAGES, 0);
2695 if (!cc->page_pool) {
2696 ti->error = "Cannot allocate page mempool";
2697 goto bad;
2698 }
2699
2700 cc->bs = bioset_create(MIN_IOS, 0, (BIOSET_NEED_BVECS |
2701 BIOSET_NEED_RESCUER));
2702 if (!cc->bs) {
2703 ti->error = "Cannot allocate crypt bioset";
2704 goto bad;
2705 }
2706
2707 mutex_init(&cc->bio_alloc_lock);
2708
2709 ret = -EINVAL;
2710 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
2711 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
2712 ti->error = "Invalid iv_offset sector";
2713 goto bad;
2714 }
2715 cc->iv_offset = tmpll;
2716
2717 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
2718 if (ret) {
2719 ti->error = "Device lookup failed";
2720 goto bad;
2721 }
2722
2723 ret = -EINVAL;
2724 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) {
2725 ti->error = "Invalid device sector";
2726 goto bad;
2727 }
2728 cc->start = tmpll;
2729
2730 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
2731 ret = crypt_integrity_ctr(cc, ti);
2732 if (ret)
2733 goto bad;
2734
2735 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
2736 if (!cc->tag_pool_max_sectors)
2737 cc->tag_pool_max_sectors = 1;
2738
2739 cc->tag_pool = mempool_create_kmalloc_pool(MIN_IOS,
2740 cc->tag_pool_max_sectors * cc->on_disk_tag_size);
2741 if (!cc->tag_pool) {
2742 ti->error = "Cannot allocate integrity tags mempool";
2743 goto bad;
2744 }
2745
2746 cc->tag_pool_max_sectors <<= cc->sector_shift;
2747 }
2748
2749 ret = -ENOMEM;
2750 cc->io_queue = alloc_workqueue("kcryptd_io", WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
2751 if (!cc->io_queue) {
2752 ti->error = "Couldn't create kcryptd io queue";
2753 goto bad;
2754 }
2755
2756 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
2757 cc->crypt_queue = alloc_workqueue("kcryptd", WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
2758 else
2759 cc->crypt_queue = alloc_workqueue("kcryptd",
2760 WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
2761 num_online_cpus());
2762 if (!cc->crypt_queue) {
2763 ti->error = "Couldn't create kcryptd queue";
2764 goto bad;
2765 }
2766
2767 init_waitqueue_head(&cc->write_thread_wait);
2768 cc->write_tree = RB_ROOT;
2769
2770 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write");
2771 if (IS_ERR(cc->write_thread)) {
2772 ret = PTR_ERR(cc->write_thread);
2773 cc->write_thread = NULL;
2774 ti->error = "Couldn't spawn write thread";
2775 goto bad;
2776 }
2777 wake_up_process(cc->write_thread);
2778
2779 ti->num_flush_bios = 1;
2780
2781 return 0;
2782
2783 bad:
2784 crypt_dtr(ti);
2785 return ret;
2786 }
2787
2788 static int crypt_map(struct dm_target *ti, struct bio *bio)
2789 {
2790 struct dm_crypt_io *io;
2791 struct crypt_config *cc = ti->private;
2792
2793 /*
2794 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
2795 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
2796 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
2797 */
2798 if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
2799 bio_op(bio) == REQ_OP_DISCARD)) {
2800 bio_set_dev(bio, cc->dev->bdev);
2801 if (bio_sectors(bio))
2802 bio->bi_iter.bi_sector = cc->start +
2803 dm_target_offset(ti, bio->bi_iter.bi_sector);
2804 return DM_MAPIO_REMAPPED;
2805 }
2806
2807 /*
2808 * Check if bio is too large, split as needed.
2809 */
2810 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) &&
2811 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
2812 dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT));
2813
2814 /*
2815 * Ensure that bio is a multiple of internal sector encryption size
2816 * and is aligned to this size as defined in IO hints.
2817 */
2818 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
2819 return DM_MAPIO_KILL;
2820
2821 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
2822 return DM_MAPIO_KILL;
2823
2824 io = dm_per_bio_data(bio, cc->per_bio_data_size);
2825 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
2826
2827 if (cc->on_disk_tag_size) {
2828 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
2829
2830 if (unlikely(tag_len > KMALLOC_MAX_SIZE) ||
2831 unlikely(!(io->integrity_metadata = kmalloc(tag_len,
2832 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) {
2833 if (bio_sectors(bio) > cc->tag_pool_max_sectors)
2834 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
2835 io->integrity_metadata = mempool_alloc(cc->tag_pool, GFP_NOIO);
2836 io->integrity_metadata_from_pool = true;
2837 }
2838 }
2839
2840 if (crypt_integrity_aead(cc))
2841 io->ctx.r.req_aead = (struct aead_request *)(io + 1);
2842 else
2843 io->ctx.r.req = (struct skcipher_request *)(io + 1);
2844
2845 if (bio_data_dir(io->base_bio) == READ) {
2846 if (kcryptd_io_read(io, GFP_NOWAIT))
2847 kcryptd_queue_read(io);
2848 } else
2849 kcryptd_queue_crypt(io);
2850
2851 return DM_MAPIO_SUBMITTED;
2852 }
2853
2854 static void crypt_status(struct dm_target *ti, status_type_t type,
2855 unsigned status_flags, char *result, unsigned maxlen)
2856 {
2857 struct crypt_config *cc = ti->private;
2858 unsigned i, sz = 0;
2859 int num_feature_args = 0;
2860
2861 switch (type) {
2862 case STATUSTYPE_INFO:
2863 result[0] = '\0';
2864 break;
2865
2866 case STATUSTYPE_TABLE:
2867 DMEMIT("%s ", cc->cipher_string);
2868
2869 if (cc->key_size > 0) {
2870 if (cc->key_string)
2871 DMEMIT(":%u:%s", cc->key_size, cc->key_string);
2872 else
2873 for (i = 0; i < cc->key_size; i++)
2874 DMEMIT("%02x", cc->key[i]);
2875 } else
2876 DMEMIT("-");
2877
2878 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
2879 cc->dev->name, (unsigned long long)cc->start);
2880
2881 num_feature_args += !!ti->num_discard_bios;
2882 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
2883 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
2884 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
2885 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
2886 if (cc->on_disk_tag_size)
2887 num_feature_args++;
2888 if (num_feature_args) {
2889 DMEMIT(" %d", num_feature_args);
2890 if (ti->num_discard_bios)
2891 DMEMIT(" allow_discards");
2892 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
2893 DMEMIT(" same_cpu_crypt");
2894 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
2895 DMEMIT(" submit_from_crypt_cpus");
2896 if (cc->on_disk_tag_size)
2897 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
2898 if (cc->sector_size != (1 << SECTOR_SHIFT))
2899 DMEMIT(" sector_size:%d", cc->sector_size);
2900 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
2901 DMEMIT(" iv_large_sectors");
2902 }
2903
2904 break;
2905 }
2906 }
2907
2908 static void crypt_postsuspend(struct dm_target *ti)
2909 {
2910 struct crypt_config *cc = ti->private;
2911
2912 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
2913 }
2914
2915 static int crypt_preresume(struct dm_target *ti)
2916 {
2917 struct crypt_config *cc = ti->private;
2918
2919 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
2920 DMERR("aborting resume - crypt key is not set.");
2921 return -EAGAIN;
2922 }
2923
2924 return 0;
2925 }
2926
2927 static void crypt_resume(struct dm_target *ti)
2928 {
2929 struct crypt_config *cc = ti->private;
2930
2931 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
2932 }
2933
2934 /* Message interface
2935 * key set <key>
2936 * key wipe
2937 */
2938 static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
2939 {
2940 struct crypt_config *cc = ti->private;
2941 int key_size, ret = -EINVAL;
2942
2943 if (argc < 2)
2944 goto error;
2945
2946 if (!strcasecmp(argv[0], "key")) {
2947 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
2948 DMWARN("not suspended during key manipulation.");
2949 return -EINVAL;
2950 }
2951 if (argc == 3 && !strcasecmp(argv[1], "set")) {
2952 /* The key size may not be changed. */
2953 key_size = get_key_size(&argv[2]);
2954 if (key_size < 0 || cc->key_size != key_size) {
2955 memset(argv[2], '0', strlen(argv[2]));
2956 return -EINVAL;
2957 }
2958
2959 ret = crypt_set_key(cc, argv[2]);
2960 if (ret)
2961 return ret;
2962 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
2963 ret = cc->iv_gen_ops->init(cc);
2964 return ret;
2965 }
2966 if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
2967 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2968 ret = cc->iv_gen_ops->wipe(cc);
2969 if (ret)
2970 return ret;
2971 }
2972 return crypt_wipe_key(cc);
2973 }
2974 }
2975
2976 error:
2977 DMWARN("unrecognised message received.");
2978 return -EINVAL;
2979 }
2980
2981 static int crypt_iterate_devices(struct dm_target *ti,
2982 iterate_devices_callout_fn fn, void *data)
2983 {
2984 struct crypt_config *cc = ti->private;
2985
2986 return fn(ti, cc->dev, cc->start, ti->len, data);
2987 }
2988
2989 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
2990 {
2991 struct crypt_config *cc = ti->private;
2992
2993 /*
2994 * Unfortunate constraint that is required to avoid the potential
2995 * for exceeding underlying device's max_segments limits -- due to
2996 * crypt_alloc_buffer() possibly allocating pages for the encryption
2997 * bio that are not as physically contiguous as the original bio.
2998 */
2999 limits->max_segment_size = PAGE_SIZE;
3000
3001 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
3002 limits->logical_block_size = cc->sector_size;
3003 limits->physical_block_size = cc->sector_size;
3004 blk_limits_io_min(limits, cc->sector_size);
3005 }
3006 }
3007
3008 static struct target_type crypt_target = {
3009 .name = "crypt",
3010 .version = {1, 18, 0},
3011 .module = THIS_MODULE,
3012 .ctr = crypt_ctr,
3013 .dtr = crypt_dtr,
3014 .map = crypt_map,
3015 .status = crypt_status,
3016 .postsuspend = crypt_postsuspend,
3017 .preresume = crypt_preresume,
3018 .resume = crypt_resume,
3019 .message = crypt_message,
3020 .iterate_devices = crypt_iterate_devices,
3021 .io_hints = crypt_io_hints,
3022 };
3023
3024 static int __init dm_crypt_init(void)
3025 {
3026 int r;
3027
3028 r = dm_register_target(&crypt_target);
3029 if (r < 0)
3030 DMERR("register failed %d", r);
3031
3032 return r;
3033 }
3034
3035 static void __exit dm_crypt_exit(void)
3036 {
3037 dm_unregister_target(&crypt_target);
3038 }
3039
3040 module_init(dm_crypt_init);
3041 module_exit(dm_crypt_exit);
3042
3043 MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3044 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3045 MODULE_LICENSE("GPL");
Linux with added FPC-III support