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