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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2003 Jana Saout <jana@saout.de>
4 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
5 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved.
6 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com>
7 *
8 * This file is released under the GPL.
9 */
10
11#include <linux/completion.h>
12#include <linux/err.h>
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/kernel.h>
16#include <linux/key.h>
17#include <linux/bio.h>
18#include <linux/blkdev.h>
19#include <linux/blk-integrity.h>
20#include <linux/mempool.h>
21#include <linux/slab.h>
22#include <linux/crypto.h>
23#include <linux/workqueue.h>
24#include <linux/kthread.h>
25#include <linux/backing-dev.h>
26#include <linux/atomic.h>
27#include <linux/scatterlist.h>
28#include <linux/rbtree.h>
29#include <linux/ctype.h>
30#include <asm/page.h>
31#include <asm/unaligned.h>
32#include <crypto/hash.h>
33#include <crypto/md5.h>
34#include <crypto/skcipher.h>
35#include <crypto/aead.h>
36#include <crypto/authenc.h>
37#include <crypto/utils.h>
38#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
39#include <linux/key-type.h>
40#include <keys/user-type.h>
41#include <keys/encrypted-type.h>
42#include <keys/trusted-type.h>
43
44#include <linux/device-mapper.h>
45
46#include "dm-audit.h"
47
48#define DM_MSG_PREFIX "crypt"
49
50/*
51 * context holding the current state of a multi-part conversion
52 */
53struct convert_context {
54 struct completion restart;
55 struct bio *bio_in;
56 struct bvec_iter iter_in;
57 struct bio *bio_out;
58 struct bvec_iter iter_out;
59 atomic_t cc_pending;
60 u64 cc_sector;
61 union {
62 struct skcipher_request *req;
63 struct aead_request *req_aead;
64 } r;
65 bool aead_recheck;
66 bool aead_failed;
67
68};
69
70/*
71 * per bio private data
72 */
73struct dm_crypt_io {
74 struct crypt_config *cc;
75 struct bio *base_bio;
76 u8 *integrity_metadata;
77 bool integrity_metadata_from_pool:1;
78
79 struct work_struct work;
80
81 struct convert_context ctx;
82
83 atomic_t io_pending;
84 blk_status_t error;
85 sector_t sector;
86
87 struct bvec_iter saved_bi_iter;
88
89 struct rb_node rb_node;
90} CRYPTO_MINALIGN_ATTR;
91
92struct dm_crypt_request {
93 struct convert_context *ctx;
94 struct scatterlist sg_in[4];
95 struct scatterlist sg_out[4];
96 u64 iv_sector;
97};
98
99struct crypt_config;
100
101struct crypt_iv_operations {
102 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
103 const char *opts);
104 void (*dtr)(struct crypt_config *cc);
105 int (*init)(struct crypt_config *cc);
106 int (*wipe)(struct crypt_config *cc);
107 int (*generator)(struct crypt_config *cc, u8 *iv,
108 struct dm_crypt_request *dmreq);
109 int (*post)(struct crypt_config *cc, u8 *iv,
110 struct dm_crypt_request *dmreq);
111};
112
113struct iv_benbi_private {
114 int shift;
115};
116
117#define LMK_SEED_SIZE 64 /* hash + 0 */
118struct iv_lmk_private {
119 struct crypto_shash *hash_tfm;
120 u8 *seed;
121};
122
123#define TCW_WHITENING_SIZE 16
124struct iv_tcw_private {
125 struct crypto_shash *crc32_tfm;
126 u8 *iv_seed;
127 u8 *whitening;
128};
129
130#define ELEPHANT_MAX_KEY_SIZE 32
131struct iv_elephant_private {
132 struct crypto_skcipher *tfm;
133};
134
135/*
136 * Crypt: maps a linear range of a block device
137 * and encrypts / decrypts at the same time.
138 */
139enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
140 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD,
141 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE,
142 DM_CRYPT_WRITE_INLINE };
143
144enum cipher_flags {
145 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */
146 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */
147 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */
148};
149
150/*
151 * The fields in here must be read only after initialization.
152 */
153struct crypt_config {
154 struct dm_dev *dev;
155 sector_t start;
156
157 struct percpu_counter n_allocated_pages;
158
159 struct workqueue_struct *io_queue;
160 struct workqueue_struct *crypt_queue;
161
162 spinlock_t write_thread_lock;
163 struct task_struct *write_thread;
164 struct rb_root write_tree;
165
166 char *cipher_string;
167 char *cipher_auth;
168 char *key_string;
169
170 const struct crypt_iv_operations *iv_gen_ops;
171 union {
172 struct iv_benbi_private benbi;
173 struct iv_lmk_private lmk;
174 struct iv_tcw_private tcw;
175 struct iv_elephant_private elephant;
176 } iv_gen_private;
177 u64 iv_offset;
178 unsigned int iv_size;
179 unsigned short sector_size;
180 unsigned char sector_shift;
181
182 union {
183 struct crypto_skcipher **tfms;
184 struct crypto_aead **tfms_aead;
185 } cipher_tfm;
186 unsigned int 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 /*
217 * pool for per bio private data, crypto requests,
218 * encryption requeusts/buffer pages and integrity tags
219 */
220 unsigned int tag_pool_max_sectors;
221 mempool_t tag_pool;
222 mempool_t req_pool;
223 mempool_t page_pool;
224
225 struct bio_set bs;
226 struct mutex bio_alloc_lock;
227
228 u8 *authenc_key; /* space for keys in authenc() format (if used) */
229 u8 key[] __counted_by(key_size);
230};
231
232#define MIN_IOS 64
233#define MAX_TAG_SIZE 480
234#define POOL_ENTRY_SIZE 512
235
236static DEFINE_SPINLOCK(dm_crypt_clients_lock);
237static unsigned int dm_crypt_clients_n;
238static volatile unsigned long dm_crypt_pages_per_client;
239#define DM_CRYPT_MEMORY_PERCENT 2
240#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16)
241
242static void crypt_endio(struct bio *clone);
243static void kcryptd_queue_crypt(struct dm_crypt_io *io);
244static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
245 struct scatterlist *sg);
246
247static bool crypt_integrity_aead(struct crypt_config *cc);
248
249/*
250 * Use this to access cipher attributes that are independent of the key.
251 */
252static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
253{
254 return cc->cipher_tfm.tfms[0];
255}
256
257static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
258{
259 return cc->cipher_tfm.tfms_aead[0];
260}
261
262/*
263 * Different IV generation algorithms:
264 *
265 * plain: the initial vector is the 32-bit little-endian version of the sector
266 * number, padded with zeros if necessary.
267 *
268 * plain64: the initial vector is the 64-bit little-endian version of the sector
269 * number, padded with zeros if necessary.
270 *
271 * plain64be: the initial vector is the 64-bit big-endian version of the sector
272 * number, padded with zeros if necessary.
273 *
274 * essiv: "encrypted sector|salt initial vector", the sector number is
275 * encrypted with the bulk cipher using a salt as key. The salt
276 * should be derived from the bulk cipher's key via hashing.
277 *
278 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
279 * (needed for LRW-32-AES and possible other narrow block modes)
280 *
281 * null: the initial vector is always zero. Provides compatibility with
282 * obsolete loop_fish2 devices. Do not use for new devices.
283 *
284 * lmk: Compatible implementation of the block chaining mode used
285 * by the Loop-AES block device encryption system
286 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
287 * It operates on full 512 byte sectors and uses CBC
288 * with an IV derived from the sector number, the data and
289 * optionally extra IV seed.
290 * This means that after decryption the first block
291 * of sector must be tweaked according to decrypted data.
292 * Loop-AES can use three encryption schemes:
293 * version 1: is plain aes-cbc mode
294 * version 2: uses 64 multikey scheme with lmk IV generator
295 * version 3: the same as version 2 with additional IV seed
296 * (it uses 65 keys, last key is used as IV seed)
297 *
298 * tcw: Compatible implementation of the block chaining mode used
299 * by the TrueCrypt device encryption system (prior to version 4.1).
300 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
301 * It operates on full 512 byte sectors and uses CBC
302 * with an IV derived from initial key and the sector number.
303 * In addition, whitening value is applied on every sector, whitening
304 * is calculated from initial key, sector number and mixed using CRC32.
305 * Note that this encryption scheme is vulnerable to watermarking attacks
306 * and should be used for old compatible containers access only.
307 *
308 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
309 * The IV is encrypted little-endian byte-offset (with the same key
310 * and cipher as the volume).
311 *
312 * elephant: The extended version of eboiv with additional Elephant diffuser
313 * used with Bitlocker CBC mode.
314 * This mode was used in older Windows systems
315 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
316 */
317
318static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
319 struct dm_crypt_request *dmreq)
320{
321 memset(iv, 0, cc->iv_size);
322 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
323
324 return 0;
325}
326
327static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
328 struct dm_crypt_request *dmreq)
329{
330 memset(iv, 0, cc->iv_size);
331 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
332
333 return 0;
334}
335
336static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
337 struct dm_crypt_request *dmreq)
338{
339 memset(iv, 0, cc->iv_size);
340 /* iv_size is at least of size u64; usually it is 16 bytes */
341 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
342
343 return 0;
344}
345
346static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
347 struct dm_crypt_request *dmreq)
348{
349 /*
350 * ESSIV encryption of the IV is now handled by the crypto API,
351 * so just pass the plain sector number here.
352 */
353 memset(iv, 0, cc->iv_size);
354 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
355
356 return 0;
357}
358
359static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
360 const char *opts)
361{
362 unsigned int bs;
363 int log;
364
365 if (crypt_integrity_aead(cc))
366 bs = crypto_aead_blocksize(any_tfm_aead(cc));
367 else
368 bs = crypto_skcipher_blocksize(any_tfm(cc));
369 log = ilog2(bs);
370
371 /*
372 * We need to calculate how far we must shift the sector count
373 * to get the cipher block count, we use this shift in _gen.
374 */
375 if (1 << log != bs) {
376 ti->error = "cypher blocksize is not a power of 2";
377 return -EINVAL;
378 }
379
380 if (log > 9) {
381 ti->error = "cypher blocksize is > 512";
382 return -EINVAL;
383 }
384
385 cc->iv_gen_private.benbi.shift = 9 - log;
386
387 return 0;
388}
389
390static void crypt_iv_benbi_dtr(struct crypt_config *cc)
391{
392}
393
394static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
395 struct dm_crypt_request *dmreq)
396{
397 __be64 val;
398
399 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
400
401 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
402 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
403
404 return 0;
405}
406
407static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
408 struct dm_crypt_request *dmreq)
409{
410 memset(iv, 0, cc->iv_size);
411
412 return 0;
413}
414
415static void crypt_iv_lmk_dtr(struct crypt_config *cc)
416{
417 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
418
419 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
420 crypto_free_shash(lmk->hash_tfm);
421 lmk->hash_tfm = NULL;
422
423 kfree_sensitive(lmk->seed);
424 lmk->seed = NULL;
425}
426
427static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
428 const char *opts)
429{
430 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
431
432 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
433 ti->error = "Unsupported sector size for LMK";
434 return -EINVAL;
435 }
436
437 lmk->hash_tfm = crypto_alloc_shash("md5", 0,
438 CRYPTO_ALG_ALLOCATES_MEMORY);
439 if (IS_ERR(lmk->hash_tfm)) {
440 ti->error = "Error initializing LMK hash";
441 return PTR_ERR(lmk->hash_tfm);
442 }
443
444 /* No seed in LMK version 2 */
445 if (cc->key_parts == cc->tfms_count) {
446 lmk->seed = NULL;
447 return 0;
448 }
449
450 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
451 if (!lmk->seed) {
452 crypt_iv_lmk_dtr(cc);
453 ti->error = "Error kmallocing seed storage in LMK";
454 return -ENOMEM;
455 }
456
457 return 0;
458}
459
460static int crypt_iv_lmk_init(struct crypt_config *cc)
461{
462 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
463 int subkey_size = cc->key_size / cc->key_parts;
464
465 /* LMK seed is on the position of LMK_KEYS + 1 key */
466 if (lmk->seed)
467 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
468 crypto_shash_digestsize(lmk->hash_tfm));
469
470 return 0;
471}
472
473static int crypt_iv_lmk_wipe(struct crypt_config *cc)
474{
475 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
476
477 if (lmk->seed)
478 memset(lmk->seed, 0, LMK_SEED_SIZE);
479
480 return 0;
481}
482
483static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
484 struct dm_crypt_request *dmreq,
485 u8 *data)
486{
487 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
488 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
489 struct md5_state md5state;
490 __le32 buf[4];
491 int i, r;
492
493 desc->tfm = lmk->hash_tfm;
494
495 r = crypto_shash_init(desc);
496 if (r)
497 return r;
498
499 if (lmk->seed) {
500 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
501 if (r)
502 return r;
503 }
504
505 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
506 r = crypto_shash_update(desc, data + 16, 16 * 31);
507 if (r)
508 return r;
509
510 /* Sector is cropped to 56 bits here */
511 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
512 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
513 buf[2] = cpu_to_le32(4024);
514 buf[3] = 0;
515 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
516 if (r)
517 return r;
518
519 /* No MD5 padding here */
520 r = crypto_shash_export(desc, &md5state);
521 if (r)
522 return r;
523
524 for (i = 0; i < MD5_HASH_WORDS; i++)
525 __cpu_to_le32s(&md5state.hash[i]);
526 memcpy(iv, &md5state.hash, cc->iv_size);
527
528 return 0;
529}
530
531static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
532 struct dm_crypt_request *dmreq)
533{
534 struct scatterlist *sg;
535 u8 *src;
536 int r = 0;
537
538 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
539 sg = crypt_get_sg_data(cc, dmreq->sg_in);
540 src = kmap_local_page(sg_page(sg));
541 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
542 kunmap_local(src);
543 } else
544 memset(iv, 0, cc->iv_size);
545
546 return r;
547}
548
549static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
550 struct dm_crypt_request *dmreq)
551{
552 struct scatterlist *sg;
553 u8 *dst;
554 int r;
555
556 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
557 return 0;
558
559 sg = crypt_get_sg_data(cc, dmreq->sg_out);
560 dst = kmap_local_page(sg_page(sg));
561 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
562
563 /* Tweak the first block of plaintext sector */
564 if (!r)
565 crypto_xor(dst + sg->offset, iv, cc->iv_size);
566
567 kunmap_local(dst);
568 return r;
569}
570
571static void crypt_iv_tcw_dtr(struct crypt_config *cc)
572{
573 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
574
575 kfree_sensitive(tcw->iv_seed);
576 tcw->iv_seed = NULL;
577 kfree_sensitive(tcw->whitening);
578 tcw->whitening = NULL;
579
580 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
581 crypto_free_shash(tcw->crc32_tfm);
582 tcw->crc32_tfm = NULL;
583}
584
585static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
586 const char *opts)
587{
588 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
589
590 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
591 ti->error = "Unsupported sector size for TCW";
592 return -EINVAL;
593 }
594
595 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
596 ti->error = "Wrong key size for TCW";
597 return -EINVAL;
598 }
599
600 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0,
601 CRYPTO_ALG_ALLOCATES_MEMORY);
602 if (IS_ERR(tcw->crc32_tfm)) {
603 ti->error = "Error initializing CRC32 in TCW";
604 return PTR_ERR(tcw->crc32_tfm);
605 }
606
607 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
608 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
609 if (!tcw->iv_seed || !tcw->whitening) {
610 crypt_iv_tcw_dtr(cc);
611 ti->error = "Error allocating seed storage in TCW";
612 return -ENOMEM;
613 }
614
615 return 0;
616}
617
618static int crypt_iv_tcw_init(struct crypt_config *cc)
619{
620 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
621 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
622
623 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
624 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
625 TCW_WHITENING_SIZE);
626
627 return 0;
628}
629
630static int crypt_iv_tcw_wipe(struct crypt_config *cc)
631{
632 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
633
634 memset(tcw->iv_seed, 0, cc->iv_size);
635 memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
636
637 return 0;
638}
639
640static int crypt_iv_tcw_whitening(struct crypt_config *cc,
641 struct dm_crypt_request *dmreq,
642 u8 *data)
643{
644 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
645 __le64 sector = cpu_to_le64(dmreq->iv_sector);
646 u8 buf[TCW_WHITENING_SIZE];
647 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
648 int i, r;
649
650 /* xor whitening with sector number */
651 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8);
652 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8);
653
654 /* calculate crc32 for every 32bit part and xor it */
655 desc->tfm = tcw->crc32_tfm;
656 for (i = 0; i < 4; i++) {
657 r = crypto_shash_digest(desc, &buf[i * 4], 4, &buf[i * 4]);
658 if (r)
659 goto out;
660 }
661 crypto_xor(&buf[0], &buf[12], 4);
662 crypto_xor(&buf[4], &buf[8], 4);
663
664 /* apply whitening (8 bytes) to whole sector */
665 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
666 crypto_xor(data + i * 8, buf, 8);
667out:
668 memzero_explicit(buf, sizeof(buf));
669 return r;
670}
671
672static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
673 struct dm_crypt_request *dmreq)
674{
675 struct scatterlist *sg;
676 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
677 __le64 sector = cpu_to_le64(dmreq->iv_sector);
678 u8 *src;
679 int r = 0;
680
681 /* Remove whitening from ciphertext */
682 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
683 sg = crypt_get_sg_data(cc, dmreq->sg_in);
684 src = kmap_local_page(sg_page(sg));
685 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
686 kunmap_local(src);
687 }
688
689 /* Calculate IV */
690 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8);
691 if (cc->iv_size > 8)
692 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or,
693 cc->iv_size - 8);
694
695 return r;
696}
697
698static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
699 struct dm_crypt_request *dmreq)
700{
701 struct scatterlist *sg;
702 u8 *dst;
703 int r;
704
705 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
706 return 0;
707
708 /* Apply whitening on ciphertext */
709 sg = crypt_get_sg_data(cc, dmreq->sg_out);
710 dst = kmap_local_page(sg_page(sg));
711 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
712 kunmap_local(dst);
713
714 return r;
715}
716
717static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
718 struct dm_crypt_request *dmreq)
719{
720 /* Used only for writes, there must be an additional space to store IV */
721 get_random_bytes(iv, cc->iv_size);
722 return 0;
723}
724
725static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
726 const char *opts)
727{
728 if (crypt_integrity_aead(cc)) {
729 ti->error = "AEAD transforms not supported for EBOIV";
730 return -EINVAL;
731 }
732
733 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
734 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher";
735 return -EINVAL;
736 }
737
738 return 0;
739}
740
741static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
742 struct dm_crypt_request *dmreq)
743{
744 struct crypto_skcipher *tfm = any_tfm(cc);
745 struct skcipher_request *req;
746 struct scatterlist src, dst;
747 DECLARE_CRYPTO_WAIT(wait);
748 unsigned int reqsize;
749 int err;
750 u8 *buf;
751
752 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm);
753 reqsize = ALIGN(reqsize, __alignof__(__le64));
754
755 req = kmalloc(reqsize + cc->iv_size, GFP_NOIO);
756 if (!req)
757 return -ENOMEM;
758
759 skcipher_request_set_tfm(req, tfm);
760
761 buf = (u8 *)req + reqsize;
762 memset(buf, 0, cc->iv_size);
763 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
764
765 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
766 sg_init_one(&dst, iv, cc->iv_size);
767 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
768 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
769 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
770 kfree_sensitive(req);
771
772 return err;
773}
774
775static void crypt_iv_elephant_dtr(struct crypt_config *cc)
776{
777 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
778
779 crypto_free_skcipher(elephant->tfm);
780 elephant->tfm = NULL;
781}
782
783static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
784 const char *opts)
785{
786 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
787 int r;
788
789 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0,
790 CRYPTO_ALG_ALLOCATES_MEMORY);
791 if (IS_ERR(elephant->tfm)) {
792 r = PTR_ERR(elephant->tfm);
793 elephant->tfm = NULL;
794 return r;
795 }
796
797 r = crypt_iv_eboiv_ctr(cc, ti, NULL);
798 if (r)
799 crypt_iv_elephant_dtr(cc);
800 return r;
801}
802
803static void diffuser_disk_to_cpu(u32 *d, size_t n)
804{
805#ifndef __LITTLE_ENDIAN
806 int i;
807
808 for (i = 0; i < n; i++)
809 d[i] = le32_to_cpu((__le32)d[i]);
810#endif
811}
812
813static void diffuser_cpu_to_disk(__le32 *d, size_t n)
814{
815#ifndef __LITTLE_ENDIAN
816 int i;
817
818 for (i = 0; i < n; i++)
819 d[i] = cpu_to_le32((u32)d[i]);
820#endif
821}
822
823static void diffuser_a_decrypt(u32 *d, size_t n)
824{
825 int i, i1, i2, i3;
826
827 for (i = 0; i < 5; i++) {
828 i1 = 0;
829 i2 = n - 2;
830 i3 = n - 5;
831
832 while (i1 < (n - 1)) {
833 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
834 i1++; i2++; i3++;
835
836 if (i3 >= n)
837 i3 -= n;
838
839 d[i1] += d[i2] ^ d[i3];
840 i1++; i2++; i3++;
841
842 if (i2 >= n)
843 i2 -= n;
844
845 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
846 i1++; i2++; i3++;
847
848 d[i1] += d[i2] ^ d[i3];
849 i1++; i2++; i3++;
850 }
851 }
852}
853
854static void diffuser_a_encrypt(u32 *d, size_t n)
855{
856 int i, i1, i2, i3;
857
858 for (i = 0; i < 5; i++) {
859 i1 = n - 1;
860 i2 = n - 2 - 1;
861 i3 = n - 5 - 1;
862
863 while (i1 > 0) {
864 d[i1] -= d[i2] ^ d[i3];
865 i1--; i2--; i3--;
866
867 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
868 i1--; i2--; i3--;
869
870 if (i2 < 0)
871 i2 += n;
872
873 d[i1] -= d[i2] ^ d[i3];
874 i1--; i2--; i3--;
875
876 if (i3 < 0)
877 i3 += n;
878
879 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
880 i1--; i2--; i3--;
881 }
882 }
883}
884
885static void diffuser_b_decrypt(u32 *d, size_t n)
886{
887 int i, i1, i2, i3;
888
889 for (i = 0; i < 3; i++) {
890 i1 = 0;
891 i2 = 2;
892 i3 = 5;
893
894 while (i1 < (n - 1)) {
895 d[i1] += d[i2] ^ d[i3];
896 i1++; i2++; i3++;
897
898 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
899 i1++; i2++; i3++;
900
901 if (i2 >= n)
902 i2 -= n;
903
904 d[i1] += d[i2] ^ d[i3];
905 i1++; i2++; i3++;
906
907 if (i3 >= n)
908 i3 -= n;
909
910 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
911 i1++; i2++; i3++;
912 }
913 }
914}
915
916static void diffuser_b_encrypt(u32 *d, size_t n)
917{
918 int i, i1, i2, i3;
919
920 for (i = 0; i < 3; i++) {
921 i1 = n - 1;
922 i2 = 2 - 1;
923 i3 = 5 - 1;
924
925 while (i1 > 0) {
926 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
927 i1--; i2--; i3--;
928
929 if (i3 < 0)
930 i3 += n;
931
932 d[i1] -= d[i2] ^ d[i3];
933 i1--; i2--; i3--;
934
935 if (i2 < 0)
936 i2 += n;
937
938 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
939 i1--; i2--; i3--;
940
941 d[i1] -= d[i2] ^ d[i3];
942 i1--; i2--; i3--;
943 }
944 }
945}
946
947static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq)
948{
949 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
950 u8 *es, *ks, *data, *data2, *data_offset;
951 struct skcipher_request *req;
952 struct scatterlist *sg, *sg2, src, dst;
953 DECLARE_CRYPTO_WAIT(wait);
954 int i, r;
955
956 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO);
957 es = kzalloc(16, GFP_NOIO); /* Key for AES */
958 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */
959
960 if (!req || !es || !ks) {
961 r = -ENOMEM;
962 goto out;
963 }
964
965 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
966
967 /* E(Ks, e(s)) */
968 sg_init_one(&src, es, 16);
969 sg_init_one(&dst, ks, 16);
970 skcipher_request_set_crypt(req, &src, &dst, 16, NULL);
971 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
972 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
973 if (r)
974 goto out;
975
976 /* E(Ks, e'(s)) */
977 es[15] = 0x80;
978 sg_init_one(&dst, &ks[16], 16);
979 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
980 if (r)
981 goto out;
982
983 sg = crypt_get_sg_data(cc, dmreq->sg_out);
984 data = kmap_local_page(sg_page(sg));
985 data_offset = data + sg->offset;
986
987 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */
988 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
989 sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
990 data2 = kmap_local_page(sg_page(sg2));
991 memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
992 kunmap_local(data2);
993 }
994
995 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
996 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32));
997 diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
998 diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
999 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32));
1000 }
1001
1002 for (i = 0; i < (cc->sector_size / 32); i++)
1003 crypto_xor(data_offset + i * 32, ks, 32);
1004
1005 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1006 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32));
1007 diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
1008 diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
1009 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32));
1010 }
1011
1012 kunmap_local(data);
1013out:
1014 kfree_sensitive(ks);
1015 kfree_sensitive(es);
1016 skcipher_request_free(req);
1017 return r;
1018}
1019
1020static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
1021 struct dm_crypt_request *dmreq)
1022{
1023 int r;
1024
1025 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1026 r = crypt_iv_elephant(cc, dmreq);
1027 if (r)
1028 return r;
1029 }
1030
1031 return crypt_iv_eboiv_gen(cc, iv, dmreq);
1032}
1033
1034static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
1035 struct dm_crypt_request *dmreq)
1036{
1037 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
1038 return crypt_iv_elephant(cc, dmreq);
1039
1040 return 0;
1041}
1042
1043static int crypt_iv_elephant_init(struct crypt_config *cc)
1044{
1045 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1046 int key_offset = cc->key_size - cc->key_extra_size;
1047
1048 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size);
1049}
1050
1051static int crypt_iv_elephant_wipe(struct crypt_config *cc)
1052{
1053 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1054 u8 key[ELEPHANT_MAX_KEY_SIZE];
1055
1056 memset(key, 0, cc->key_extra_size);
1057 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size);
1058}
1059
1060static const struct crypt_iv_operations crypt_iv_plain_ops = {
1061 .generator = crypt_iv_plain_gen
1062};
1063
1064static const struct crypt_iv_operations crypt_iv_plain64_ops = {
1065 .generator = crypt_iv_plain64_gen
1066};
1067
1068static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
1069 .generator = crypt_iv_plain64be_gen
1070};
1071
1072static const struct crypt_iv_operations crypt_iv_essiv_ops = {
1073 .generator = crypt_iv_essiv_gen
1074};
1075
1076static const struct crypt_iv_operations crypt_iv_benbi_ops = {
1077 .ctr = crypt_iv_benbi_ctr,
1078 .dtr = crypt_iv_benbi_dtr,
1079 .generator = crypt_iv_benbi_gen
1080};
1081
1082static const struct crypt_iv_operations crypt_iv_null_ops = {
1083 .generator = crypt_iv_null_gen
1084};
1085
1086static const struct crypt_iv_operations crypt_iv_lmk_ops = {
1087 .ctr = crypt_iv_lmk_ctr,
1088 .dtr = crypt_iv_lmk_dtr,
1089 .init = crypt_iv_lmk_init,
1090 .wipe = crypt_iv_lmk_wipe,
1091 .generator = crypt_iv_lmk_gen,
1092 .post = crypt_iv_lmk_post
1093};
1094
1095static const struct crypt_iv_operations crypt_iv_tcw_ops = {
1096 .ctr = crypt_iv_tcw_ctr,
1097 .dtr = crypt_iv_tcw_dtr,
1098 .init = crypt_iv_tcw_init,
1099 .wipe = crypt_iv_tcw_wipe,
1100 .generator = crypt_iv_tcw_gen,
1101 .post = crypt_iv_tcw_post
1102};
1103
1104static const struct crypt_iv_operations crypt_iv_random_ops = {
1105 .generator = crypt_iv_random_gen
1106};
1107
1108static const struct crypt_iv_operations crypt_iv_eboiv_ops = {
1109 .ctr = crypt_iv_eboiv_ctr,
1110 .generator = crypt_iv_eboiv_gen
1111};
1112
1113static const struct crypt_iv_operations crypt_iv_elephant_ops = {
1114 .ctr = crypt_iv_elephant_ctr,
1115 .dtr = crypt_iv_elephant_dtr,
1116 .init = crypt_iv_elephant_init,
1117 .wipe = crypt_iv_elephant_wipe,
1118 .generator = crypt_iv_elephant_gen,
1119 .post = crypt_iv_elephant_post
1120};
1121
1122/*
1123 * Integrity extensions
1124 */
1125static bool crypt_integrity_aead(struct crypt_config *cc)
1126{
1127 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
1128}
1129
1130static bool crypt_integrity_hmac(struct crypt_config *cc)
1131{
1132 return crypt_integrity_aead(cc) && cc->key_mac_size;
1133}
1134
1135/* Get sg containing data */
1136static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
1137 struct scatterlist *sg)
1138{
1139 if (unlikely(crypt_integrity_aead(cc)))
1140 return &sg[2];
1141
1142 return sg;
1143}
1144
1145static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
1146{
1147 struct bio_integrity_payload *bip;
1148 unsigned int tag_len;
1149 int ret;
1150
1151 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
1152 return 0;
1153
1154 bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
1155 if (IS_ERR(bip))
1156 return PTR_ERR(bip);
1157
1158 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift);
1159
1160 bip->bip_iter.bi_sector = io->cc->start + io->sector;
1161
1162 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
1163 tag_len, offset_in_page(io->integrity_metadata));
1164 if (unlikely(ret != tag_len))
1165 return -ENOMEM;
1166
1167 return 0;
1168}
1169
1170static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
1171{
1172#ifdef CONFIG_BLK_DEV_INTEGRITY
1173 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
1174 struct mapped_device *md = dm_table_get_md(ti->table);
1175
1176 /* From now we require underlying device with our integrity profile */
1177 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
1178 ti->error = "Integrity profile not supported.";
1179 return -EINVAL;
1180 }
1181
1182 if (bi->tag_size != cc->on_disk_tag_size ||
1183 bi->tuple_size != cc->on_disk_tag_size) {
1184 ti->error = "Integrity profile tag size mismatch.";
1185 return -EINVAL;
1186 }
1187 if (1 << bi->interval_exp != cc->sector_size) {
1188 ti->error = "Integrity profile sector size mismatch.";
1189 return -EINVAL;
1190 }
1191
1192 if (crypt_integrity_aead(cc)) {
1193 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
1194 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
1195 cc->integrity_tag_size, cc->integrity_iv_size);
1196
1197 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
1198 ti->error = "Integrity AEAD auth tag size is not supported.";
1199 return -EINVAL;
1200 }
1201 } else if (cc->integrity_iv_size)
1202 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
1203 cc->integrity_iv_size);
1204
1205 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
1206 ti->error = "Not enough space for integrity tag in the profile.";
1207 return -EINVAL;
1208 }
1209
1210 return 0;
1211#else
1212 ti->error = "Integrity profile not supported.";
1213 return -EINVAL;
1214#endif
1215}
1216
1217static void crypt_convert_init(struct crypt_config *cc,
1218 struct convert_context *ctx,
1219 struct bio *bio_out, struct bio *bio_in,
1220 sector_t sector)
1221{
1222 ctx->bio_in = bio_in;
1223 ctx->bio_out = bio_out;
1224 if (bio_in)
1225 ctx->iter_in = bio_in->bi_iter;
1226 if (bio_out)
1227 ctx->iter_out = bio_out->bi_iter;
1228 ctx->cc_sector = sector + cc->iv_offset;
1229 init_completion(&ctx->restart);
1230}
1231
1232static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1233 void *req)
1234{
1235 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1236}
1237
1238static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1239{
1240 return (void *)((char *)dmreq - cc->dmreq_start);
1241}
1242
1243static u8 *iv_of_dmreq(struct crypt_config *cc,
1244 struct dm_crypt_request *dmreq)
1245{
1246 if (crypt_integrity_aead(cc))
1247 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1248 crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1249 else
1250 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1251 crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1252}
1253
1254static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1255 struct dm_crypt_request *dmreq)
1256{
1257 return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1258}
1259
1260static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
1261 struct dm_crypt_request *dmreq)
1262{
1263 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
1264
1265 return (__le64 *) ptr;
1266}
1267
1268static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1269 struct dm_crypt_request *dmreq)
1270{
1271 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1272 cc->iv_size + sizeof(uint64_t);
1273
1274 return (unsigned int *)ptr;
1275}
1276
1277static void *tag_from_dmreq(struct crypt_config *cc,
1278 struct dm_crypt_request *dmreq)
1279{
1280 struct convert_context *ctx = dmreq->ctx;
1281 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1282
1283 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1284 cc->on_disk_tag_size];
1285}
1286
1287static void *iv_tag_from_dmreq(struct crypt_config *cc,
1288 struct dm_crypt_request *dmreq)
1289{
1290 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1291}
1292
1293static int crypt_convert_block_aead(struct crypt_config *cc,
1294 struct convert_context *ctx,
1295 struct aead_request *req,
1296 unsigned int tag_offset)
1297{
1298 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1299 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1300 struct dm_crypt_request *dmreq;
1301 u8 *iv, *org_iv, *tag_iv, *tag;
1302 __le64 *sector;
1303 int r = 0;
1304
1305 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1306
1307 /* Reject unexpected unaligned bio. */
1308 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1309 return -EIO;
1310
1311 dmreq = dmreq_of_req(cc, req);
1312 dmreq->iv_sector = ctx->cc_sector;
1313 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1314 dmreq->iv_sector >>= cc->sector_shift;
1315 dmreq->ctx = ctx;
1316
1317 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1318
1319 sector = org_sector_of_dmreq(cc, dmreq);
1320 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1321
1322 iv = iv_of_dmreq(cc, dmreq);
1323 org_iv = org_iv_of_dmreq(cc, dmreq);
1324 tag = tag_from_dmreq(cc, dmreq);
1325 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1326
1327 /* AEAD request:
1328 * |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1329 * | (authenticated) | (auth+encryption) | |
1330 * | sector_LE | IV | sector in/out | tag in/out |
1331 */
1332 sg_init_table(dmreq->sg_in, 4);
1333 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1334 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1335 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1336 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1337
1338 sg_init_table(dmreq->sg_out, 4);
1339 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1340 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1341 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1342 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1343
1344 if (cc->iv_gen_ops) {
1345 /* For READs use IV stored in integrity metadata */
1346 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1347 memcpy(org_iv, tag_iv, cc->iv_size);
1348 } else {
1349 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1350 if (r < 0)
1351 return r;
1352 /* Store generated IV in integrity metadata */
1353 if (cc->integrity_iv_size)
1354 memcpy(tag_iv, org_iv, cc->iv_size);
1355 }
1356 /* Working copy of IV, to be modified in crypto API */
1357 memcpy(iv, org_iv, cc->iv_size);
1358 }
1359
1360 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1361 if (bio_data_dir(ctx->bio_in) == WRITE) {
1362 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1363 cc->sector_size, iv);
1364 r = crypto_aead_encrypt(req);
1365 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
1366 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1367 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1368 } else {
1369 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1370 cc->sector_size + cc->integrity_tag_size, iv);
1371 r = crypto_aead_decrypt(req);
1372 }
1373
1374 if (r == -EBADMSG) {
1375 sector_t s = le64_to_cpu(*sector);
1376
1377 ctx->aead_failed = true;
1378 if (ctx->aead_recheck) {
1379 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
1380 ctx->bio_in->bi_bdev, s);
1381 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
1382 ctx->bio_in, s, 0);
1383 }
1384 }
1385
1386 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1387 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1388
1389 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1390 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1391
1392 return r;
1393}
1394
1395static int crypt_convert_block_skcipher(struct crypt_config *cc,
1396 struct convert_context *ctx,
1397 struct skcipher_request *req,
1398 unsigned int tag_offset)
1399{
1400 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1401 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1402 struct scatterlist *sg_in, *sg_out;
1403 struct dm_crypt_request *dmreq;
1404 u8 *iv, *org_iv, *tag_iv;
1405 __le64 *sector;
1406 int r = 0;
1407
1408 /* Reject unexpected unaligned bio. */
1409 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1410 return -EIO;
1411
1412 dmreq = dmreq_of_req(cc, req);
1413 dmreq->iv_sector = ctx->cc_sector;
1414 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1415 dmreq->iv_sector >>= cc->sector_shift;
1416 dmreq->ctx = ctx;
1417
1418 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1419
1420 iv = iv_of_dmreq(cc, dmreq);
1421 org_iv = org_iv_of_dmreq(cc, dmreq);
1422 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1423
1424 sector = org_sector_of_dmreq(cc, dmreq);
1425 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1426
1427 /* For skcipher we use only the first sg item */
1428 sg_in = &dmreq->sg_in[0];
1429 sg_out = &dmreq->sg_out[0];
1430
1431 sg_init_table(sg_in, 1);
1432 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1433
1434 sg_init_table(sg_out, 1);
1435 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1436
1437 if (cc->iv_gen_ops) {
1438 /* For READs use IV stored in integrity metadata */
1439 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1440 memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1441 } else {
1442 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1443 if (r < 0)
1444 return r;
1445 /* Data can be already preprocessed in generator */
1446 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
1447 sg_in = sg_out;
1448 /* Store generated IV in integrity metadata */
1449 if (cc->integrity_iv_size)
1450 memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1451 }
1452 /* Working copy of IV, to be modified in crypto API */
1453 memcpy(iv, org_iv, cc->iv_size);
1454 }
1455
1456 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1457
1458 if (bio_data_dir(ctx->bio_in) == WRITE)
1459 r = crypto_skcipher_encrypt(req);
1460 else
1461 r = crypto_skcipher_decrypt(req);
1462
1463 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1464 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1465
1466 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1467 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1468
1469 return r;
1470}
1471
1472static void kcryptd_async_done(void *async_req, int error);
1473
1474static int crypt_alloc_req_skcipher(struct crypt_config *cc,
1475 struct convert_context *ctx)
1476{
1477 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1);
1478
1479 if (!ctx->r.req) {
1480 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1481 if (!ctx->r.req)
1482 return -ENOMEM;
1483 }
1484
1485 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1486
1487 /*
1488 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1489 * requests if driver request queue is full.
1490 */
1491 skcipher_request_set_callback(ctx->r.req,
1492 CRYPTO_TFM_REQ_MAY_BACKLOG,
1493 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
1494
1495 return 0;
1496}
1497
1498static int crypt_alloc_req_aead(struct crypt_config *cc,
1499 struct convert_context *ctx)
1500{
1501 if (!ctx->r.req_aead) {
1502 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1503 if (!ctx->r.req_aead)
1504 return -ENOMEM;
1505 }
1506
1507 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1508
1509 /*
1510 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1511 * requests if driver request queue is full.
1512 */
1513 aead_request_set_callback(ctx->r.req_aead,
1514 CRYPTO_TFM_REQ_MAY_BACKLOG,
1515 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
1516
1517 return 0;
1518}
1519
1520static int crypt_alloc_req(struct crypt_config *cc,
1521 struct convert_context *ctx)
1522{
1523 if (crypt_integrity_aead(cc))
1524 return crypt_alloc_req_aead(cc, ctx);
1525 else
1526 return crypt_alloc_req_skcipher(cc, ctx);
1527}
1528
1529static void crypt_free_req_skcipher(struct crypt_config *cc,
1530 struct skcipher_request *req, struct bio *base_bio)
1531{
1532 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1533
1534 if ((struct skcipher_request *)(io + 1) != req)
1535 mempool_free(req, &cc->req_pool);
1536}
1537
1538static void crypt_free_req_aead(struct crypt_config *cc,
1539 struct aead_request *req, struct bio *base_bio)
1540{
1541 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1542
1543 if ((struct aead_request *)(io + 1) != req)
1544 mempool_free(req, &cc->req_pool);
1545}
1546
1547static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1548{
1549 if (crypt_integrity_aead(cc))
1550 crypt_free_req_aead(cc, req, base_bio);
1551 else
1552 crypt_free_req_skcipher(cc, req, base_bio);
1553}
1554
1555/*
1556 * Encrypt / decrypt data from one bio to another one (can be the same one)
1557 */
1558static blk_status_t crypt_convert(struct crypt_config *cc,
1559 struct convert_context *ctx, bool atomic, bool reset_pending)
1560{
1561 unsigned int tag_offset = 0;
1562 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1563 int r;
1564
1565 /*
1566 * if reset_pending is set we are dealing with the bio for the first time,
1567 * else we're continuing to work on the previous bio, so don't mess with
1568 * the cc_pending counter
1569 */
1570 if (reset_pending)
1571 atomic_set(&ctx->cc_pending, 1);
1572
1573 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1574
1575 r = crypt_alloc_req(cc, ctx);
1576 if (r) {
1577 complete(&ctx->restart);
1578 return BLK_STS_DEV_RESOURCE;
1579 }
1580
1581 atomic_inc(&ctx->cc_pending);
1582
1583 if (crypt_integrity_aead(cc))
1584 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
1585 else
1586 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
1587
1588 switch (r) {
1589 /*
1590 * The request was queued by a crypto driver
1591 * but the driver request queue is full, let's wait.
1592 */
1593 case -EBUSY:
1594 if (in_interrupt()) {
1595 if (try_wait_for_completion(&ctx->restart)) {
1596 /*
1597 * we don't have to block to wait for completion,
1598 * so proceed
1599 */
1600 } else {
1601 /*
1602 * we can't wait for completion without blocking
1603 * exit and continue processing in a workqueue
1604 */
1605 ctx->r.req = NULL;
1606 ctx->cc_sector += sector_step;
1607 tag_offset++;
1608 return BLK_STS_DEV_RESOURCE;
1609 }
1610 } else {
1611 wait_for_completion(&ctx->restart);
1612 }
1613 reinit_completion(&ctx->restart);
1614 fallthrough;
1615 /*
1616 * The request is queued and processed asynchronously,
1617 * completion function kcryptd_async_done() will be called.
1618 */
1619 case -EINPROGRESS:
1620 ctx->r.req = NULL;
1621 ctx->cc_sector += sector_step;
1622 tag_offset++;
1623 continue;
1624 /*
1625 * The request was already processed (synchronously).
1626 */
1627 case 0:
1628 atomic_dec(&ctx->cc_pending);
1629 ctx->cc_sector += sector_step;
1630 tag_offset++;
1631 if (!atomic)
1632 cond_resched();
1633 continue;
1634 /*
1635 * There was a data integrity error.
1636 */
1637 case -EBADMSG:
1638 atomic_dec(&ctx->cc_pending);
1639 return BLK_STS_PROTECTION;
1640 /*
1641 * There was an error while processing the request.
1642 */
1643 default:
1644 atomic_dec(&ctx->cc_pending);
1645 return BLK_STS_IOERR;
1646 }
1647 }
1648
1649 return 0;
1650}
1651
1652static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1653
1654/*
1655 * Generate a new unfragmented bio with the given size
1656 * This should never violate the device limitations (but only because
1657 * max_segment_size is being constrained to PAGE_SIZE).
1658 *
1659 * This function may be called concurrently. If we allocate from the mempool
1660 * concurrently, there is a possibility of deadlock. For example, if we have
1661 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1662 * the mempool concurrently, it may deadlock in a situation where both processes
1663 * have allocated 128 pages and the mempool is exhausted.
1664 *
1665 * In order to avoid this scenario we allocate the pages under a mutex.
1666 *
1667 * In order to not degrade performance with excessive locking, we try
1668 * non-blocking allocations without a mutex first but on failure we fallback
1669 * to blocking allocations with a mutex.
1670 *
1671 * In order to reduce allocation overhead, we try to allocate compound pages in
1672 * the first pass. If they are not available, we fall back to the mempool.
1673 */
1674static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size)
1675{
1676 struct crypt_config *cc = io->cc;
1677 struct bio *clone;
1678 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1679 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1680 unsigned int remaining_size;
1681 unsigned int order = MAX_PAGE_ORDER;
1682
1683retry:
1684 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1685 mutex_lock(&cc->bio_alloc_lock);
1686
1687 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf,
1688 GFP_NOIO, &cc->bs);
1689 clone->bi_private = io;
1690 clone->bi_end_io = crypt_endio;
1691
1692 remaining_size = size;
1693
1694 while (remaining_size) {
1695 struct page *pages;
1696 unsigned size_to_add;
1697 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT);
1698 order = min(order, remaining_order);
1699
1700 while (order > 0) {
1701 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) +
1702 (1 << order) > dm_crypt_pages_per_client))
1703 goto decrease_order;
1704 pages = alloc_pages(gfp_mask
1705 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP,
1706 order);
1707 if (likely(pages != NULL)) {
1708 percpu_counter_add(&cc->n_allocated_pages, 1 << order);
1709 goto have_pages;
1710 }
1711decrease_order:
1712 order--;
1713 }
1714
1715 pages = mempool_alloc(&cc->page_pool, gfp_mask);
1716 if (!pages) {
1717 crypt_free_buffer_pages(cc, clone);
1718 bio_put(clone);
1719 gfp_mask |= __GFP_DIRECT_RECLAIM;
1720 order = 0;
1721 goto retry;
1722 }
1723
1724have_pages:
1725 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size);
1726 __bio_add_page(clone, pages, size_to_add, 0);
1727 remaining_size -= size_to_add;
1728 }
1729
1730 /* Allocate space for integrity tags */
1731 if (dm_crypt_integrity_io_alloc(io, clone)) {
1732 crypt_free_buffer_pages(cc, clone);
1733 bio_put(clone);
1734 clone = NULL;
1735 }
1736
1737 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1738 mutex_unlock(&cc->bio_alloc_lock);
1739
1740 return clone;
1741}
1742
1743static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1744{
1745 struct folio_iter fi;
1746
1747 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */
1748 bio_for_each_folio_all(fi, clone) {
1749 if (folio_test_large(fi.folio)) {
1750 percpu_counter_sub(&cc->n_allocated_pages,
1751 1 << folio_order(fi.folio));
1752 folio_put(fi.folio);
1753 } else {
1754 mempool_free(&fi.folio->page, &cc->page_pool);
1755 }
1756 }
1757 }
1758}
1759
1760static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1761 struct bio *bio, sector_t sector)
1762{
1763 io->cc = cc;
1764 io->base_bio = bio;
1765 io->sector = sector;
1766 io->error = 0;
1767 io->ctx.aead_recheck = false;
1768 io->ctx.aead_failed = false;
1769 io->ctx.r.req = NULL;
1770 io->integrity_metadata = NULL;
1771 io->integrity_metadata_from_pool = false;
1772 atomic_set(&io->io_pending, 0);
1773}
1774
1775static void crypt_inc_pending(struct dm_crypt_io *io)
1776{
1777 atomic_inc(&io->io_pending);
1778}
1779
1780static void kcryptd_queue_read(struct dm_crypt_io *io);
1781
1782/*
1783 * One of the bios was finished. Check for completion of
1784 * the whole request and correctly clean up the buffer.
1785 */
1786static void crypt_dec_pending(struct dm_crypt_io *io)
1787{
1788 struct crypt_config *cc = io->cc;
1789 struct bio *base_bio = io->base_bio;
1790 blk_status_t error = io->error;
1791
1792 if (!atomic_dec_and_test(&io->io_pending))
1793 return;
1794
1795 if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) &&
1796 cc->on_disk_tag_size && bio_data_dir(base_bio) == READ) {
1797 io->ctx.aead_recheck = true;
1798 io->ctx.aead_failed = false;
1799 io->error = 0;
1800 kcryptd_queue_read(io);
1801 return;
1802 }
1803
1804 if (io->ctx.r.req)
1805 crypt_free_req(cc, io->ctx.r.req, base_bio);
1806
1807 if (unlikely(io->integrity_metadata_from_pool))
1808 mempool_free(io->integrity_metadata, &io->cc->tag_pool);
1809 else
1810 kfree(io->integrity_metadata);
1811
1812 base_bio->bi_status = error;
1813
1814 bio_endio(base_bio);
1815}
1816
1817/*
1818 * kcryptd/kcryptd_io:
1819 *
1820 * Needed because it would be very unwise to do decryption in an
1821 * interrupt context.
1822 *
1823 * kcryptd performs the actual encryption or decryption.
1824 *
1825 * kcryptd_io performs the IO submission.
1826 *
1827 * They must be separated as otherwise the final stages could be
1828 * starved by new requests which can block in the first stages due
1829 * to memory allocation.
1830 *
1831 * The work is done per CPU global for all dm-crypt instances.
1832 * They should not depend on each other and do not block.
1833 */
1834static void crypt_endio(struct bio *clone)
1835{
1836 struct dm_crypt_io *io = clone->bi_private;
1837 struct crypt_config *cc = io->cc;
1838 unsigned int rw = bio_data_dir(clone);
1839 blk_status_t error = clone->bi_status;
1840
1841 if (io->ctx.aead_recheck && !error) {
1842 kcryptd_queue_crypt(io);
1843 return;
1844 }
1845
1846 /*
1847 * free the processed pages
1848 */
1849 if (rw == WRITE || io->ctx.aead_recheck)
1850 crypt_free_buffer_pages(cc, clone);
1851
1852 bio_put(clone);
1853
1854 if (rw == READ && !error) {
1855 kcryptd_queue_crypt(io);
1856 return;
1857 }
1858
1859 if (unlikely(error))
1860 io->error = error;
1861
1862 crypt_dec_pending(io);
1863}
1864
1865#define CRYPT_MAP_READ_GFP GFP_NOWAIT
1866
1867static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1868{
1869 struct crypt_config *cc = io->cc;
1870 struct bio *clone;
1871
1872 if (io->ctx.aead_recheck) {
1873 if (!(gfp & __GFP_DIRECT_RECLAIM))
1874 return 1;
1875 crypt_inc_pending(io);
1876 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1877 if (unlikely(!clone)) {
1878 crypt_dec_pending(io);
1879 return 1;
1880 }
1881 clone->bi_iter.bi_sector = cc->start + io->sector;
1882 crypt_convert_init(cc, &io->ctx, clone, clone, io->sector);
1883 io->saved_bi_iter = clone->bi_iter;
1884 dm_submit_bio_remap(io->base_bio, clone);
1885 return 0;
1886 }
1887
1888 /*
1889 * We need the original biovec array in order to decrypt the whole bio
1890 * data *afterwards* -- thanks to immutable biovecs we don't need to
1891 * worry about the block layer modifying the biovec array; so leverage
1892 * bio_alloc_clone().
1893 */
1894 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs);
1895 if (!clone)
1896 return 1;
1897 clone->bi_private = io;
1898 clone->bi_end_io = crypt_endio;
1899
1900 crypt_inc_pending(io);
1901
1902 clone->bi_iter.bi_sector = cc->start + io->sector;
1903
1904 if (dm_crypt_integrity_io_alloc(io, clone)) {
1905 crypt_dec_pending(io);
1906 bio_put(clone);
1907 return 1;
1908 }
1909
1910 dm_submit_bio_remap(io->base_bio, clone);
1911 return 0;
1912}
1913
1914static void kcryptd_io_read_work(struct work_struct *work)
1915{
1916 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1917
1918 crypt_inc_pending(io);
1919 if (kcryptd_io_read(io, GFP_NOIO))
1920 io->error = BLK_STS_RESOURCE;
1921 crypt_dec_pending(io);
1922}
1923
1924static void kcryptd_queue_read(struct dm_crypt_io *io)
1925{
1926 struct crypt_config *cc = io->cc;
1927
1928 INIT_WORK(&io->work, kcryptd_io_read_work);
1929 queue_work(cc->io_queue, &io->work);
1930}
1931
1932static void kcryptd_io_write(struct dm_crypt_io *io)
1933{
1934 struct bio *clone = io->ctx.bio_out;
1935
1936 dm_submit_bio_remap(io->base_bio, clone);
1937}
1938
1939#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1940
1941static int dmcrypt_write(void *data)
1942{
1943 struct crypt_config *cc = data;
1944 struct dm_crypt_io *io;
1945
1946 while (1) {
1947 struct rb_root write_tree;
1948 struct blk_plug plug;
1949
1950 spin_lock_irq(&cc->write_thread_lock);
1951continue_locked:
1952
1953 if (!RB_EMPTY_ROOT(&cc->write_tree))
1954 goto pop_from_list;
1955
1956 set_current_state(TASK_INTERRUPTIBLE);
1957
1958 spin_unlock_irq(&cc->write_thread_lock);
1959
1960 if (unlikely(kthread_should_stop())) {
1961 set_current_state(TASK_RUNNING);
1962 break;
1963 }
1964
1965 schedule();
1966
1967 set_current_state(TASK_RUNNING);
1968 spin_lock_irq(&cc->write_thread_lock);
1969 goto continue_locked;
1970
1971pop_from_list:
1972 write_tree = cc->write_tree;
1973 cc->write_tree = RB_ROOT;
1974 spin_unlock_irq(&cc->write_thread_lock);
1975
1976 BUG_ON(rb_parent(write_tree.rb_node));
1977
1978 /*
1979 * Note: we cannot walk the tree here with rb_next because
1980 * the structures may be freed when kcryptd_io_write is called.
1981 */
1982 blk_start_plug(&plug);
1983 do {
1984 io = crypt_io_from_node(rb_first(&write_tree));
1985 rb_erase(&io->rb_node, &write_tree);
1986 kcryptd_io_write(io);
1987 cond_resched();
1988 } while (!RB_EMPTY_ROOT(&write_tree));
1989 blk_finish_plug(&plug);
1990 }
1991 return 0;
1992}
1993
1994static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1995{
1996 struct bio *clone = io->ctx.bio_out;
1997 struct crypt_config *cc = io->cc;
1998 unsigned long flags;
1999 sector_t sector;
2000 struct rb_node **rbp, *parent;
2001
2002 if (unlikely(io->error)) {
2003 crypt_free_buffer_pages(cc, clone);
2004 bio_put(clone);
2005 crypt_dec_pending(io);
2006 return;
2007 }
2008
2009 /* crypt_convert should have filled the clone bio */
2010 BUG_ON(io->ctx.iter_out.bi_size);
2011
2012 clone->bi_iter.bi_sector = cc->start + io->sector;
2013
2014 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
2015 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
2016 dm_submit_bio_remap(io->base_bio, clone);
2017 return;
2018 }
2019
2020 spin_lock_irqsave(&cc->write_thread_lock, flags);
2021 if (RB_EMPTY_ROOT(&cc->write_tree))
2022 wake_up_process(cc->write_thread);
2023 rbp = &cc->write_tree.rb_node;
2024 parent = NULL;
2025 sector = io->sector;
2026 while (*rbp) {
2027 parent = *rbp;
2028 if (sector < crypt_io_from_node(parent)->sector)
2029 rbp = &(*rbp)->rb_left;
2030 else
2031 rbp = &(*rbp)->rb_right;
2032 }
2033 rb_link_node(&io->rb_node, parent, rbp);
2034 rb_insert_color(&io->rb_node, &cc->write_tree);
2035 spin_unlock_irqrestore(&cc->write_thread_lock, flags);
2036}
2037
2038static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
2039 struct convert_context *ctx)
2040
2041{
2042 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
2043 return false;
2044
2045 /*
2046 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
2047 * constraints so they do not need to be issued inline by
2048 * kcryptd_crypt_write_convert().
2049 */
2050 switch (bio_op(ctx->bio_in)) {
2051 case REQ_OP_WRITE:
2052 case REQ_OP_WRITE_ZEROES:
2053 return true;
2054 default:
2055 return false;
2056 }
2057}
2058
2059static void kcryptd_crypt_write_continue(struct work_struct *work)
2060{
2061 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2062 struct crypt_config *cc = io->cc;
2063 struct convert_context *ctx = &io->ctx;
2064 int crypt_finished;
2065 sector_t sector = io->sector;
2066 blk_status_t r;
2067
2068 wait_for_completion(&ctx->restart);
2069 reinit_completion(&ctx->restart);
2070
2071 r = crypt_convert(cc, &io->ctx, true, false);
2072 if (r)
2073 io->error = r;
2074 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2075 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2076 /* Wait for completion signaled by kcryptd_async_done() */
2077 wait_for_completion(&ctx->restart);
2078 crypt_finished = 1;
2079 }
2080
2081 /* Encryption was already finished, submit io now */
2082 if (crypt_finished) {
2083 kcryptd_crypt_write_io_submit(io, 0);
2084 io->sector = sector;
2085 }
2086
2087 crypt_dec_pending(io);
2088}
2089
2090static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
2091{
2092 struct crypt_config *cc = io->cc;
2093 struct convert_context *ctx = &io->ctx;
2094 struct bio *clone;
2095 int crypt_finished;
2096 sector_t sector = io->sector;
2097 blk_status_t r;
2098
2099 /*
2100 * Prevent io from disappearing until this function completes.
2101 */
2102 crypt_inc_pending(io);
2103 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector);
2104
2105 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
2106 if (unlikely(!clone)) {
2107 io->error = BLK_STS_IOERR;
2108 goto dec;
2109 }
2110
2111 io->ctx.bio_out = clone;
2112 io->ctx.iter_out = clone->bi_iter;
2113
2114 if (crypt_integrity_aead(cc)) {
2115 bio_copy_data(clone, io->base_bio);
2116 io->ctx.bio_in = clone;
2117 io->ctx.iter_in = clone->bi_iter;
2118 }
2119
2120 sector += bio_sectors(clone);
2121
2122 crypt_inc_pending(io);
2123 r = crypt_convert(cc, ctx,
2124 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true);
2125 /*
2126 * Crypto API backlogged the request, because its queue was full
2127 * and we're in softirq context, so continue from a workqueue
2128 * (TODO: is it actually possible to be in softirq in the write path?)
2129 */
2130 if (r == BLK_STS_DEV_RESOURCE) {
2131 INIT_WORK(&io->work, kcryptd_crypt_write_continue);
2132 queue_work(cc->crypt_queue, &io->work);
2133 return;
2134 }
2135 if (r)
2136 io->error = r;
2137 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2138 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2139 /* Wait for completion signaled by kcryptd_async_done() */
2140 wait_for_completion(&ctx->restart);
2141 crypt_finished = 1;
2142 }
2143
2144 /* Encryption was already finished, submit io now */
2145 if (crypt_finished) {
2146 kcryptd_crypt_write_io_submit(io, 0);
2147 io->sector = sector;
2148 }
2149
2150dec:
2151 crypt_dec_pending(io);
2152}
2153
2154static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
2155{
2156 if (io->ctx.aead_recheck) {
2157 if (!io->error) {
2158 io->ctx.bio_in->bi_iter = io->saved_bi_iter;
2159 bio_copy_data(io->base_bio, io->ctx.bio_in);
2160 }
2161 crypt_free_buffer_pages(io->cc, io->ctx.bio_in);
2162 bio_put(io->ctx.bio_in);
2163 }
2164 crypt_dec_pending(io);
2165}
2166
2167static void kcryptd_crypt_read_continue(struct work_struct *work)
2168{
2169 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2170 struct crypt_config *cc = io->cc;
2171 blk_status_t r;
2172
2173 wait_for_completion(&io->ctx.restart);
2174 reinit_completion(&io->ctx.restart);
2175
2176 r = crypt_convert(cc, &io->ctx, true, false);
2177 if (r)
2178 io->error = r;
2179
2180 if (atomic_dec_and_test(&io->ctx.cc_pending))
2181 kcryptd_crypt_read_done(io);
2182
2183 crypt_dec_pending(io);
2184}
2185
2186static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
2187{
2188 struct crypt_config *cc = io->cc;
2189 blk_status_t r;
2190
2191 crypt_inc_pending(io);
2192
2193 if (io->ctx.aead_recheck) {
2194 io->ctx.cc_sector = io->sector + cc->iv_offset;
2195 r = crypt_convert(cc, &io->ctx,
2196 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2197 } else {
2198 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
2199 io->sector);
2200
2201 r = crypt_convert(cc, &io->ctx,
2202 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2203 }
2204 /*
2205 * Crypto API backlogged the request, because its queue was full
2206 * and we're in softirq context, so continue from a workqueue
2207 */
2208 if (r == BLK_STS_DEV_RESOURCE) {
2209 INIT_WORK(&io->work, kcryptd_crypt_read_continue);
2210 queue_work(cc->crypt_queue, &io->work);
2211 return;
2212 }
2213 if (r)
2214 io->error = r;
2215
2216 if (atomic_dec_and_test(&io->ctx.cc_pending))
2217 kcryptd_crypt_read_done(io);
2218
2219 crypt_dec_pending(io);
2220}
2221
2222static void kcryptd_async_done(void *data, int error)
2223{
2224 struct dm_crypt_request *dmreq = data;
2225 struct convert_context *ctx = dmreq->ctx;
2226 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
2227 struct crypt_config *cc = io->cc;
2228
2229 /*
2230 * A request from crypto driver backlog is going to be processed now,
2231 * finish the completion and continue in crypt_convert().
2232 * (Callback will be called for the second time for this request.)
2233 */
2234 if (error == -EINPROGRESS) {
2235 complete(&ctx->restart);
2236 return;
2237 }
2238
2239 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
2240 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
2241
2242 if (error == -EBADMSG) {
2243 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq));
2244
2245 ctx->aead_failed = true;
2246 if (ctx->aead_recheck) {
2247 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
2248 ctx->bio_in->bi_bdev, s);
2249 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
2250 ctx->bio_in, s, 0);
2251 }
2252 io->error = BLK_STS_PROTECTION;
2253 } else if (error < 0)
2254 io->error = BLK_STS_IOERR;
2255
2256 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
2257
2258 if (!atomic_dec_and_test(&ctx->cc_pending))
2259 return;
2260
2261 /*
2262 * The request is fully completed: for inline writes, let
2263 * kcryptd_crypt_write_convert() do the IO submission.
2264 */
2265 if (bio_data_dir(io->base_bio) == READ) {
2266 kcryptd_crypt_read_done(io);
2267 return;
2268 }
2269
2270 if (kcryptd_crypt_write_inline(cc, ctx)) {
2271 complete(&ctx->restart);
2272 return;
2273 }
2274
2275 kcryptd_crypt_write_io_submit(io, 1);
2276}
2277
2278static void kcryptd_crypt(struct work_struct *work)
2279{
2280 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2281
2282 if (bio_data_dir(io->base_bio) == READ)
2283 kcryptd_crypt_read_convert(io);
2284 else
2285 kcryptd_crypt_write_convert(io);
2286}
2287
2288static void kcryptd_queue_crypt(struct dm_crypt_io *io)
2289{
2290 struct crypt_config *cc = io->cc;
2291
2292 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
2293 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
2294 /*
2295 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context.
2296 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but
2297 * it is being executed with irqs disabled.
2298 */
2299 if (!(in_hardirq() || irqs_disabled())) {
2300 kcryptd_crypt(&io->work);
2301 return;
2302 }
2303 }
2304
2305 INIT_WORK(&io->work, kcryptd_crypt);
2306 queue_work(cc->crypt_queue, &io->work);
2307}
2308
2309static void crypt_free_tfms_aead(struct crypt_config *cc)
2310{
2311 if (!cc->cipher_tfm.tfms_aead)
2312 return;
2313
2314 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2315 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
2316 cc->cipher_tfm.tfms_aead[0] = NULL;
2317 }
2318
2319 kfree(cc->cipher_tfm.tfms_aead);
2320 cc->cipher_tfm.tfms_aead = NULL;
2321}
2322
2323static void crypt_free_tfms_skcipher(struct crypt_config *cc)
2324{
2325 unsigned int i;
2326
2327 if (!cc->cipher_tfm.tfms)
2328 return;
2329
2330 for (i = 0; i < cc->tfms_count; i++)
2331 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
2332 crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
2333 cc->cipher_tfm.tfms[i] = NULL;
2334 }
2335
2336 kfree(cc->cipher_tfm.tfms);
2337 cc->cipher_tfm.tfms = NULL;
2338}
2339
2340static void crypt_free_tfms(struct crypt_config *cc)
2341{
2342 if (crypt_integrity_aead(cc))
2343 crypt_free_tfms_aead(cc);
2344 else
2345 crypt_free_tfms_skcipher(cc);
2346}
2347
2348static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
2349{
2350 unsigned int i;
2351 int err;
2352
2353 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count,
2354 sizeof(struct crypto_skcipher *),
2355 GFP_KERNEL);
2356 if (!cc->cipher_tfm.tfms)
2357 return -ENOMEM;
2358
2359 for (i = 0; i < cc->tfms_count; i++) {
2360 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0,
2361 CRYPTO_ALG_ALLOCATES_MEMORY);
2362 if (IS_ERR(cc->cipher_tfm.tfms[i])) {
2363 err = PTR_ERR(cc->cipher_tfm.tfms[i]);
2364 crypt_free_tfms(cc);
2365 return err;
2366 }
2367 }
2368
2369 /*
2370 * dm-crypt performance can vary greatly depending on which crypto
2371 * algorithm implementation is used. Help people debug performance
2372 * problems by logging the ->cra_driver_name.
2373 */
2374 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2375 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
2376 return 0;
2377}
2378
2379static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
2380{
2381 int err;
2382
2383 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
2384 if (!cc->cipher_tfm.tfms)
2385 return -ENOMEM;
2386
2387 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0,
2388 CRYPTO_ALG_ALLOCATES_MEMORY);
2389 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2390 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
2391 crypt_free_tfms(cc);
2392 return err;
2393 }
2394
2395 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2396 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
2397 return 0;
2398}
2399
2400static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
2401{
2402 if (crypt_integrity_aead(cc))
2403 return crypt_alloc_tfms_aead(cc, ciphermode);
2404 else
2405 return crypt_alloc_tfms_skcipher(cc, ciphermode);
2406}
2407
2408static unsigned int crypt_subkey_size(struct crypt_config *cc)
2409{
2410 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
2411}
2412
2413static unsigned int crypt_authenckey_size(struct crypt_config *cc)
2414{
2415 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
2416}
2417
2418/*
2419 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
2420 * the key must be for some reason in special format.
2421 * This funcion converts cc->key to this special format.
2422 */
2423static void crypt_copy_authenckey(char *p, const void *key,
2424 unsigned int enckeylen, unsigned int authkeylen)
2425{
2426 struct crypto_authenc_key_param *param;
2427 struct rtattr *rta;
2428
2429 rta = (struct rtattr *)p;
2430 param = RTA_DATA(rta);
2431 param->enckeylen = cpu_to_be32(enckeylen);
2432 rta->rta_len = RTA_LENGTH(sizeof(*param));
2433 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
2434 p += RTA_SPACE(sizeof(*param));
2435 memcpy(p, key + enckeylen, authkeylen);
2436 p += authkeylen;
2437 memcpy(p, key, enckeylen);
2438}
2439
2440static int crypt_setkey(struct crypt_config *cc)
2441{
2442 unsigned int subkey_size;
2443 int err = 0, i, r;
2444
2445 /* Ignore extra keys (which are used for IV etc) */
2446 subkey_size = crypt_subkey_size(cc);
2447
2448 if (crypt_integrity_hmac(cc)) {
2449 if (subkey_size < cc->key_mac_size)
2450 return -EINVAL;
2451
2452 crypt_copy_authenckey(cc->authenc_key, cc->key,
2453 subkey_size - cc->key_mac_size,
2454 cc->key_mac_size);
2455 }
2456
2457 for (i = 0; i < cc->tfms_count; i++) {
2458 if (crypt_integrity_hmac(cc))
2459 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2460 cc->authenc_key, crypt_authenckey_size(cc));
2461 else if (crypt_integrity_aead(cc))
2462 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2463 cc->key + (i * subkey_size),
2464 subkey_size);
2465 else
2466 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
2467 cc->key + (i * subkey_size),
2468 subkey_size);
2469 if (r)
2470 err = r;
2471 }
2472
2473 if (crypt_integrity_hmac(cc))
2474 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
2475
2476 return err;
2477}
2478
2479#ifdef CONFIG_KEYS
2480
2481static bool contains_whitespace(const char *str)
2482{
2483 while (*str)
2484 if (isspace(*str++))
2485 return true;
2486 return false;
2487}
2488
2489static int set_key_user(struct crypt_config *cc, struct key *key)
2490{
2491 const struct user_key_payload *ukp;
2492
2493 ukp = user_key_payload_locked(key);
2494 if (!ukp)
2495 return -EKEYREVOKED;
2496
2497 if (cc->key_size != ukp->datalen)
2498 return -EINVAL;
2499
2500 memcpy(cc->key, ukp->data, cc->key_size);
2501
2502 return 0;
2503}
2504
2505static int set_key_encrypted(struct crypt_config *cc, struct key *key)
2506{
2507 const struct encrypted_key_payload *ekp;
2508
2509 ekp = key->payload.data[0];
2510 if (!ekp)
2511 return -EKEYREVOKED;
2512
2513 if (cc->key_size != ekp->decrypted_datalen)
2514 return -EINVAL;
2515
2516 memcpy(cc->key, ekp->decrypted_data, cc->key_size);
2517
2518 return 0;
2519}
2520
2521static int set_key_trusted(struct crypt_config *cc, struct key *key)
2522{
2523 const struct trusted_key_payload *tkp;
2524
2525 tkp = key->payload.data[0];
2526 if (!tkp)
2527 return -EKEYREVOKED;
2528
2529 if (cc->key_size != tkp->key_len)
2530 return -EINVAL;
2531
2532 memcpy(cc->key, tkp->key, cc->key_size);
2533
2534 return 0;
2535}
2536
2537static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2538{
2539 char *new_key_string, *key_desc;
2540 int ret;
2541 struct key_type *type;
2542 struct key *key;
2543 int (*set_key)(struct crypt_config *cc, struct key *key);
2544
2545 /*
2546 * Reject key_string with whitespace. dm core currently lacks code for
2547 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2548 */
2549 if (contains_whitespace(key_string)) {
2550 DMERR("whitespace chars not allowed in key string");
2551 return -EINVAL;
2552 }
2553
2554 /* look for next ':' separating key_type from key_description */
2555 key_desc = strchr(key_string, ':');
2556 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2557 return -EINVAL;
2558
2559 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
2560 type = &key_type_logon;
2561 set_key = set_key_user;
2562 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
2563 type = &key_type_user;
2564 set_key = set_key_user;
2565 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) &&
2566 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
2567 type = &key_type_encrypted;
2568 set_key = set_key_encrypted;
2569 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) &&
2570 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) {
2571 type = &key_type_trusted;
2572 set_key = set_key_trusted;
2573 } else {
2574 return -EINVAL;
2575 }
2576
2577 new_key_string = kstrdup(key_string, GFP_KERNEL);
2578 if (!new_key_string)
2579 return -ENOMEM;
2580
2581 key = request_key(type, key_desc + 1, NULL);
2582 if (IS_ERR(key)) {
2583 kfree_sensitive(new_key_string);
2584 return PTR_ERR(key);
2585 }
2586
2587 down_read(&key->sem);
2588
2589 ret = set_key(cc, key);
2590 if (ret < 0) {
2591 up_read(&key->sem);
2592 key_put(key);
2593 kfree_sensitive(new_key_string);
2594 return ret;
2595 }
2596
2597 up_read(&key->sem);
2598 key_put(key);
2599
2600 /* clear the flag since following operations may invalidate previously valid key */
2601 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2602
2603 ret = crypt_setkey(cc);
2604
2605 if (!ret) {
2606 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2607 kfree_sensitive(cc->key_string);
2608 cc->key_string = new_key_string;
2609 } else
2610 kfree_sensitive(new_key_string);
2611
2612 return ret;
2613}
2614
2615static int get_key_size(char **key_string)
2616{
2617 char *colon, dummy;
2618 int ret;
2619
2620 if (*key_string[0] != ':')
2621 return strlen(*key_string) >> 1;
2622
2623 /* look for next ':' in key string */
2624 colon = strpbrk(*key_string + 1, ":");
2625 if (!colon)
2626 return -EINVAL;
2627
2628 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2629 return -EINVAL;
2630
2631 *key_string = colon;
2632
2633 /* remaining key string should be :<logon|user>:<key_desc> */
2634
2635 return ret;
2636}
2637
2638#else
2639
2640static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2641{
2642 return -EINVAL;
2643}
2644
2645static int get_key_size(char **key_string)
2646{
2647 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1);
2648}
2649
2650#endif /* CONFIG_KEYS */
2651
2652static int crypt_set_key(struct crypt_config *cc, char *key)
2653{
2654 int r = -EINVAL;
2655 int key_string_len = strlen(key);
2656
2657 /* Hyphen (which gives a key_size of zero) means there is no key. */
2658 if (!cc->key_size && strcmp(key, "-"))
2659 goto out;
2660
2661 /* ':' means the key is in kernel keyring, short-circuit normal key processing */
2662 if (key[0] == ':') {
2663 r = crypt_set_keyring_key(cc, key + 1);
2664 goto out;
2665 }
2666
2667 /* clear the flag since following operations may invalidate previously valid key */
2668 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2669
2670 /* wipe references to any kernel keyring key */
2671 kfree_sensitive(cc->key_string);
2672 cc->key_string = NULL;
2673
2674 /* Decode key from its hex representation. */
2675 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2676 goto out;
2677
2678 r = crypt_setkey(cc);
2679 if (!r)
2680 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2681
2682out:
2683 /* Hex key string not needed after here, so wipe it. */
2684 memset(key, '0', key_string_len);
2685
2686 return r;
2687}
2688
2689static int crypt_wipe_key(struct crypt_config *cc)
2690{
2691 int r;
2692
2693 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2694 get_random_bytes(&cc->key, cc->key_size);
2695
2696 /* Wipe IV private keys */
2697 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2698 r = cc->iv_gen_ops->wipe(cc);
2699 if (r)
2700 return r;
2701 }
2702
2703 kfree_sensitive(cc->key_string);
2704 cc->key_string = NULL;
2705 r = crypt_setkey(cc);
2706 memset(&cc->key, 0, cc->key_size * sizeof(u8));
2707
2708 return r;
2709}
2710
2711static void crypt_calculate_pages_per_client(void)
2712{
2713 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
2714
2715 if (!dm_crypt_clients_n)
2716 return;
2717
2718 pages /= dm_crypt_clients_n;
2719 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
2720 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
2721 dm_crypt_pages_per_client = pages;
2722}
2723
2724static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
2725{
2726 struct crypt_config *cc = pool_data;
2727 struct page *page;
2728
2729 /*
2730 * Note, percpu_counter_read_positive() may over (and under) estimate
2731 * the current usage by at most (batch - 1) * num_online_cpus() pages,
2732 * but avoids potential spinlock contention of an exact result.
2733 */
2734 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) &&
2735 likely(gfp_mask & __GFP_NORETRY))
2736 return NULL;
2737
2738 page = alloc_page(gfp_mask);
2739 if (likely(page != NULL))
2740 percpu_counter_add(&cc->n_allocated_pages, 1);
2741
2742 return page;
2743}
2744
2745static void crypt_page_free(void *page, void *pool_data)
2746{
2747 struct crypt_config *cc = pool_data;
2748
2749 __free_page(page);
2750 percpu_counter_sub(&cc->n_allocated_pages, 1);
2751}
2752
2753static void crypt_dtr(struct dm_target *ti)
2754{
2755 struct crypt_config *cc = ti->private;
2756
2757 ti->private = NULL;
2758
2759 if (!cc)
2760 return;
2761
2762 if (cc->write_thread)
2763 kthread_stop(cc->write_thread);
2764
2765 if (cc->io_queue)
2766 destroy_workqueue(cc->io_queue);
2767 if (cc->crypt_queue)
2768 destroy_workqueue(cc->crypt_queue);
2769
2770 crypt_free_tfms(cc);
2771
2772 bioset_exit(&cc->bs);
2773
2774 mempool_exit(&cc->page_pool);
2775 mempool_exit(&cc->req_pool);
2776 mempool_exit(&cc->tag_pool);
2777
2778 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
2779 percpu_counter_destroy(&cc->n_allocated_pages);
2780
2781 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2782 cc->iv_gen_ops->dtr(cc);
2783
2784 if (cc->dev)
2785 dm_put_device(ti, cc->dev);
2786
2787 kfree_sensitive(cc->cipher_string);
2788 kfree_sensitive(cc->key_string);
2789 kfree_sensitive(cc->cipher_auth);
2790 kfree_sensitive(cc->authenc_key);
2791
2792 mutex_destroy(&cc->bio_alloc_lock);
2793
2794 /* Must zero key material before freeing */
2795 kfree_sensitive(cc);
2796
2797 spin_lock(&dm_crypt_clients_lock);
2798 WARN_ON(!dm_crypt_clients_n);
2799 dm_crypt_clients_n--;
2800 crypt_calculate_pages_per_client();
2801 spin_unlock(&dm_crypt_clients_lock);
2802
2803 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1);
2804}
2805
2806static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2807{
2808 struct crypt_config *cc = ti->private;
2809
2810 if (crypt_integrity_aead(cc))
2811 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2812 else
2813 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2814
2815 if (cc->iv_size)
2816 /* at least a 64 bit sector number should fit in our buffer */
2817 cc->iv_size = max(cc->iv_size,
2818 (unsigned int)(sizeof(u64) / sizeof(u8)));
2819 else if (ivmode) {
2820 DMWARN("Selected cipher does not support IVs");
2821 ivmode = NULL;
2822 }
2823
2824 /* Choose ivmode, see comments at iv code. */
2825 if (ivmode == NULL)
2826 cc->iv_gen_ops = NULL;
2827 else if (strcmp(ivmode, "plain") == 0)
2828 cc->iv_gen_ops = &crypt_iv_plain_ops;
2829 else if (strcmp(ivmode, "plain64") == 0)
2830 cc->iv_gen_ops = &crypt_iv_plain64_ops;
2831 else if (strcmp(ivmode, "plain64be") == 0)
2832 cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2833 else if (strcmp(ivmode, "essiv") == 0)
2834 cc->iv_gen_ops = &crypt_iv_essiv_ops;
2835 else if (strcmp(ivmode, "benbi") == 0)
2836 cc->iv_gen_ops = &crypt_iv_benbi_ops;
2837 else if (strcmp(ivmode, "null") == 0)
2838 cc->iv_gen_ops = &crypt_iv_null_ops;
2839 else if (strcmp(ivmode, "eboiv") == 0)
2840 cc->iv_gen_ops = &crypt_iv_eboiv_ops;
2841 else if (strcmp(ivmode, "elephant") == 0) {
2842 cc->iv_gen_ops = &crypt_iv_elephant_ops;
2843 cc->key_parts = 2;
2844 cc->key_extra_size = cc->key_size / 2;
2845 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
2846 return -EINVAL;
2847 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
2848 } else if (strcmp(ivmode, "lmk") == 0) {
2849 cc->iv_gen_ops = &crypt_iv_lmk_ops;
2850 /*
2851 * Version 2 and 3 is recognised according
2852 * to length of provided multi-key string.
2853 * If present (version 3), last key is used as IV seed.
2854 * All keys (including IV seed) are always the same size.
2855 */
2856 if (cc->key_size % cc->key_parts) {
2857 cc->key_parts++;
2858 cc->key_extra_size = cc->key_size / cc->key_parts;
2859 }
2860 } else if (strcmp(ivmode, "tcw") == 0) {
2861 cc->iv_gen_ops = &crypt_iv_tcw_ops;
2862 cc->key_parts += 2; /* IV + whitening */
2863 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2864 } else if (strcmp(ivmode, "random") == 0) {
2865 cc->iv_gen_ops = &crypt_iv_random_ops;
2866 /* Need storage space in integrity fields. */
2867 cc->integrity_iv_size = cc->iv_size;
2868 } else {
2869 ti->error = "Invalid IV mode";
2870 return -EINVAL;
2871 }
2872
2873 return 0;
2874}
2875
2876/*
2877 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2878 * The HMAC is needed to calculate tag size (HMAC digest size).
2879 * This should be probably done by crypto-api calls (once available...)
2880 */
2881static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2882{
2883 char *start, *end, *mac_alg = NULL;
2884 struct crypto_ahash *mac;
2885
2886 if (!strstarts(cipher_api, "authenc("))
2887 return 0;
2888
2889 start = strchr(cipher_api, '(');
2890 end = strchr(cipher_api, ',');
2891 if (!start || !end || ++start > end)
2892 return -EINVAL;
2893
2894 mac_alg = kmemdup_nul(start, end - start, GFP_KERNEL);
2895 if (!mac_alg)
2896 return -ENOMEM;
2897
2898 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY);
2899 kfree(mac_alg);
2900
2901 if (IS_ERR(mac))
2902 return PTR_ERR(mac);
2903
2904 cc->key_mac_size = crypto_ahash_digestsize(mac);
2905 crypto_free_ahash(mac);
2906
2907 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2908 if (!cc->authenc_key)
2909 return -ENOMEM;
2910
2911 return 0;
2912}
2913
2914static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2915 char **ivmode, char **ivopts)
2916{
2917 struct crypt_config *cc = ti->private;
2918 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
2919 int ret = -EINVAL;
2920
2921 cc->tfms_count = 1;
2922
2923 /*
2924 * New format (capi: prefix)
2925 * capi:cipher_api_spec-iv:ivopts
2926 */
2927 tmp = &cipher_in[strlen("capi:")];
2928
2929 /* Separate IV options if present, it can contain another '-' in hash name */
2930 *ivopts = strrchr(tmp, ':');
2931 if (*ivopts) {
2932 **ivopts = '\0';
2933 (*ivopts)++;
2934 }
2935 /* Parse IV mode */
2936 *ivmode = strrchr(tmp, '-');
2937 if (*ivmode) {
2938 **ivmode = '\0';
2939 (*ivmode)++;
2940 }
2941 /* The rest is crypto API spec */
2942 cipher_api = tmp;
2943
2944 /* Alloc AEAD, can be used only in new format. */
2945 if (crypt_integrity_aead(cc)) {
2946 ret = crypt_ctr_auth_cipher(cc, cipher_api);
2947 if (ret < 0) {
2948 ti->error = "Invalid AEAD cipher spec";
2949 return ret;
2950 }
2951 }
2952
2953 if (*ivmode && !strcmp(*ivmode, "lmk"))
2954 cc->tfms_count = 64;
2955
2956 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2957 if (!*ivopts) {
2958 ti->error = "Digest algorithm missing for ESSIV mode";
2959 return -EINVAL;
2960 }
2961 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
2962 cipher_api, *ivopts);
2963 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2964 ti->error = "Cannot allocate cipher string";
2965 return -ENOMEM;
2966 }
2967 cipher_api = buf;
2968 }
2969
2970 cc->key_parts = cc->tfms_count;
2971
2972 /* Allocate cipher */
2973 ret = crypt_alloc_tfms(cc, cipher_api);
2974 if (ret < 0) {
2975 ti->error = "Error allocating crypto tfm";
2976 return ret;
2977 }
2978
2979 if (crypt_integrity_aead(cc))
2980 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2981 else
2982 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2983
2984 return 0;
2985}
2986
2987static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2988 char **ivmode, char **ivopts)
2989{
2990 struct crypt_config *cc = ti->private;
2991 char *tmp, *cipher, *chainmode, *keycount;
2992 char *cipher_api = NULL;
2993 int ret = -EINVAL;
2994 char dummy;
2995
2996 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2997 ti->error = "Bad cipher specification";
2998 return -EINVAL;
2999 }
3000
3001 /*
3002 * Legacy dm-crypt cipher specification
3003 * cipher[:keycount]-mode-iv:ivopts
3004 */
3005 tmp = cipher_in;
3006 keycount = strsep(&tmp, "-");
3007 cipher = strsep(&keycount, ":");
3008
3009 if (!keycount)
3010 cc->tfms_count = 1;
3011 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
3012 !is_power_of_2(cc->tfms_count)) {
3013 ti->error = "Bad cipher key count specification";
3014 return -EINVAL;
3015 }
3016 cc->key_parts = cc->tfms_count;
3017
3018 chainmode = strsep(&tmp, "-");
3019 *ivmode = strsep(&tmp, ":");
3020 *ivopts = tmp;
3021
3022 /*
3023 * For compatibility with the original dm-crypt mapping format, if
3024 * only the cipher name is supplied, use cbc-plain.
3025 */
3026 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
3027 chainmode = "cbc";
3028 *ivmode = "plain";
3029 }
3030
3031 if (strcmp(chainmode, "ecb") && !*ivmode) {
3032 ti->error = "IV mechanism required";
3033 return -EINVAL;
3034 }
3035
3036 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
3037 if (!cipher_api)
3038 goto bad_mem;
3039
3040 if (*ivmode && !strcmp(*ivmode, "essiv")) {
3041 if (!*ivopts) {
3042 ti->error = "Digest algorithm missing for ESSIV mode";
3043 kfree(cipher_api);
3044 return -EINVAL;
3045 }
3046 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
3047 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
3048 } else {
3049 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
3050 "%s(%s)", chainmode, cipher);
3051 }
3052 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
3053 kfree(cipher_api);
3054 goto bad_mem;
3055 }
3056
3057 /* Allocate cipher */
3058 ret = crypt_alloc_tfms(cc, cipher_api);
3059 if (ret < 0) {
3060 ti->error = "Error allocating crypto tfm";
3061 kfree(cipher_api);
3062 return ret;
3063 }
3064 kfree(cipher_api);
3065
3066 return 0;
3067bad_mem:
3068 ti->error = "Cannot allocate cipher strings";
3069 return -ENOMEM;
3070}
3071
3072static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
3073{
3074 struct crypt_config *cc = ti->private;
3075 char *ivmode = NULL, *ivopts = NULL;
3076 int ret;
3077
3078 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
3079 if (!cc->cipher_string) {
3080 ti->error = "Cannot allocate cipher strings";
3081 return -ENOMEM;
3082 }
3083
3084 if (strstarts(cipher_in, "capi:"))
3085 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
3086 else
3087 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
3088 if (ret)
3089 return ret;
3090
3091 /* Initialize IV */
3092 ret = crypt_ctr_ivmode(ti, ivmode);
3093 if (ret < 0)
3094 return ret;
3095
3096 /* Initialize and set key */
3097 ret = crypt_set_key(cc, key);
3098 if (ret < 0) {
3099 ti->error = "Error decoding and setting key";
3100 return ret;
3101 }
3102
3103 /* Allocate IV */
3104 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
3105 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
3106 if (ret < 0) {
3107 ti->error = "Error creating IV";
3108 return ret;
3109 }
3110 }
3111
3112 /* Initialize IV (set keys for ESSIV etc) */
3113 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
3114 ret = cc->iv_gen_ops->init(cc);
3115 if (ret < 0) {
3116 ti->error = "Error initialising IV";
3117 return ret;
3118 }
3119 }
3120
3121 /* wipe the kernel key payload copy */
3122 if (cc->key_string)
3123 memset(cc->key, 0, cc->key_size * sizeof(u8));
3124
3125 return ret;
3126}
3127
3128static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
3129{
3130 struct crypt_config *cc = ti->private;
3131 struct dm_arg_set as;
3132 static const struct dm_arg _args[] = {
3133 {0, 8, "Invalid number of feature args"},
3134 };
3135 unsigned int opt_params, val;
3136 const char *opt_string, *sval;
3137 char dummy;
3138 int ret;
3139
3140 /* Optional parameters */
3141 as.argc = argc;
3142 as.argv = argv;
3143
3144 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
3145 if (ret)
3146 return ret;
3147
3148 while (opt_params--) {
3149 opt_string = dm_shift_arg(&as);
3150 if (!opt_string) {
3151 ti->error = "Not enough feature arguments";
3152 return -EINVAL;
3153 }
3154
3155 if (!strcasecmp(opt_string, "allow_discards"))
3156 ti->num_discard_bios = 1;
3157
3158 else if (!strcasecmp(opt_string, "same_cpu_crypt"))
3159 set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3160
3161 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
3162 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3163 else if (!strcasecmp(opt_string, "no_read_workqueue"))
3164 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3165 else if (!strcasecmp(opt_string, "no_write_workqueue"))
3166 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3167 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
3168 if (val == 0 || val > MAX_TAG_SIZE) {
3169 ti->error = "Invalid integrity arguments";
3170 return -EINVAL;
3171 }
3172 cc->on_disk_tag_size = val;
3173 sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
3174 if (!strcasecmp(sval, "aead")) {
3175 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
3176 } else if (strcasecmp(sval, "none")) {
3177 ti->error = "Unknown integrity profile";
3178 return -EINVAL;
3179 }
3180
3181 cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
3182 if (!cc->cipher_auth)
3183 return -ENOMEM;
3184 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
3185 if (cc->sector_size < (1 << SECTOR_SHIFT) ||
3186 cc->sector_size > 4096 ||
3187 (cc->sector_size & (cc->sector_size - 1))) {
3188 ti->error = "Invalid feature value for sector_size";
3189 return -EINVAL;
3190 }
3191 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
3192 ti->error = "Device size is not multiple of sector_size feature";
3193 return -EINVAL;
3194 }
3195 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
3196 } else if (!strcasecmp(opt_string, "iv_large_sectors"))
3197 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3198 else {
3199 ti->error = "Invalid feature arguments";
3200 return -EINVAL;
3201 }
3202 }
3203
3204 return 0;
3205}
3206
3207#ifdef CONFIG_BLK_DEV_ZONED
3208static int crypt_report_zones(struct dm_target *ti,
3209 struct dm_report_zones_args *args, unsigned int nr_zones)
3210{
3211 struct crypt_config *cc = ti->private;
3212
3213 return dm_report_zones(cc->dev->bdev, cc->start,
3214 cc->start + dm_target_offset(ti, args->next_sector),
3215 args, nr_zones);
3216}
3217#else
3218#define crypt_report_zones NULL
3219#endif
3220
3221/*
3222 * Construct an encryption mapping:
3223 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
3224 */
3225static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3226{
3227 struct crypt_config *cc;
3228 const char *devname = dm_table_device_name(ti->table);
3229 int key_size;
3230 unsigned int align_mask;
3231 unsigned long long tmpll;
3232 int ret;
3233 size_t iv_size_padding, additional_req_size;
3234 char dummy;
3235
3236 if (argc < 5) {
3237 ti->error = "Not enough arguments";
3238 return -EINVAL;
3239 }
3240
3241 key_size = get_key_size(&argv[1]);
3242 if (key_size < 0) {
3243 ti->error = "Cannot parse key size";
3244 return -EINVAL;
3245 }
3246
3247 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
3248 if (!cc) {
3249 ti->error = "Cannot allocate encryption context";
3250 return -ENOMEM;
3251 }
3252 cc->key_size = key_size;
3253 cc->sector_size = (1 << SECTOR_SHIFT);
3254 cc->sector_shift = 0;
3255
3256 ti->private = cc;
3257
3258 spin_lock(&dm_crypt_clients_lock);
3259 dm_crypt_clients_n++;
3260 crypt_calculate_pages_per_client();
3261 spin_unlock(&dm_crypt_clients_lock);
3262
3263 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
3264 if (ret < 0)
3265 goto bad;
3266
3267 /* Optional parameters need to be read before cipher constructor */
3268 if (argc > 5) {
3269 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
3270 if (ret)
3271 goto bad;
3272 }
3273
3274 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
3275 if (ret < 0)
3276 goto bad;
3277
3278 if (crypt_integrity_aead(cc)) {
3279 cc->dmreq_start = sizeof(struct aead_request);
3280 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
3281 align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
3282 } else {
3283 cc->dmreq_start = sizeof(struct skcipher_request);
3284 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
3285 align_mask = crypto_skcipher_alignmask(any_tfm(cc));
3286 }
3287 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
3288
3289 if (align_mask < CRYPTO_MINALIGN) {
3290 /* Allocate the padding exactly */
3291 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
3292 & align_mask;
3293 } else {
3294 /*
3295 * If the cipher requires greater alignment than kmalloc
3296 * alignment, we don't know the exact position of the
3297 * initialization vector. We must assume worst case.
3298 */
3299 iv_size_padding = align_mask;
3300 }
3301
3302 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */
3303 additional_req_size = sizeof(struct dm_crypt_request) +
3304 iv_size_padding + cc->iv_size +
3305 cc->iv_size +
3306 sizeof(uint64_t) +
3307 sizeof(unsigned int);
3308
3309 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
3310 if (ret) {
3311 ti->error = "Cannot allocate crypt request mempool";
3312 goto bad;
3313 }
3314
3315 cc->per_bio_data_size = ti->per_io_data_size =
3316 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
3317 ARCH_DMA_MINALIGN);
3318
3319 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc);
3320 if (ret) {
3321 ti->error = "Cannot allocate page mempool";
3322 goto bad;
3323 }
3324
3325 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
3326 if (ret) {
3327 ti->error = "Cannot allocate crypt bioset";
3328 goto bad;
3329 }
3330
3331 mutex_init(&cc->bio_alloc_lock);
3332
3333 ret = -EINVAL;
3334 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
3335 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
3336 ti->error = "Invalid iv_offset sector";
3337 goto bad;
3338 }
3339 cc->iv_offset = tmpll;
3340
3341 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
3342 if (ret) {
3343 ti->error = "Device lookup failed";
3344 goto bad;
3345 }
3346
3347 ret = -EINVAL;
3348 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
3349 ti->error = "Invalid device sector";
3350 goto bad;
3351 }
3352 cc->start = tmpll;
3353
3354 if (bdev_is_zoned(cc->dev->bdev)) {
3355 /*
3356 * For zoned block devices, we need to preserve the issuer write
3357 * ordering. To do so, disable write workqueues and force inline
3358 * encryption completion.
3359 */
3360 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3361 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
3362
3363 /*
3364 * All zone append writes to a zone of a zoned block device will
3365 * have the same BIO sector, the start of the zone. When the
3366 * cypher IV mode uses sector values, all data targeting a
3367 * zone will be encrypted using the first sector numbers of the
3368 * zone. This will not result in write errors but will
3369 * cause most reads to fail as reads will use the sector values
3370 * for the actual data locations, resulting in IV mismatch.
3371 * To avoid this problem, ask DM core to emulate zone append
3372 * operations with regular writes.
3373 */
3374 DMDEBUG("Zone append operations will be emulated");
3375 ti->emulate_zone_append = true;
3376 }
3377
3378 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
3379 ret = crypt_integrity_ctr(cc, ti);
3380 if (ret)
3381 goto bad;
3382
3383 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
3384 if (!cc->tag_pool_max_sectors)
3385 cc->tag_pool_max_sectors = 1;
3386
3387 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
3388 cc->tag_pool_max_sectors * cc->on_disk_tag_size);
3389 if (ret) {
3390 ti->error = "Cannot allocate integrity tags mempool";
3391 goto bad;
3392 }
3393
3394 cc->tag_pool_max_sectors <<= cc->sector_shift;
3395 }
3396
3397 ret = -ENOMEM;
3398 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname);
3399 if (!cc->io_queue) {
3400 ti->error = "Couldn't create kcryptd io queue";
3401 goto bad;
3402 }
3403
3404 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3405 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
3406 1, devname);
3407 else
3408 cc->crypt_queue = alloc_workqueue("kcryptd/%s",
3409 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
3410 num_online_cpus(), devname);
3411 if (!cc->crypt_queue) {
3412 ti->error = "Couldn't create kcryptd queue";
3413 goto bad;
3414 }
3415
3416 spin_lock_init(&cc->write_thread_lock);
3417 cc->write_tree = RB_ROOT;
3418
3419 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
3420 if (IS_ERR(cc->write_thread)) {
3421 ret = PTR_ERR(cc->write_thread);
3422 cc->write_thread = NULL;
3423 ti->error = "Couldn't spawn write thread";
3424 goto bad;
3425 }
3426
3427 ti->num_flush_bios = 1;
3428 ti->limit_swap_bios = true;
3429 ti->accounts_remapped_io = true;
3430
3431 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1);
3432 return 0;
3433
3434bad:
3435 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0);
3436 crypt_dtr(ti);
3437 return ret;
3438}
3439
3440static int crypt_map(struct dm_target *ti, struct bio *bio)
3441{
3442 struct dm_crypt_io *io;
3443 struct crypt_config *cc = ti->private;
3444
3445 /*
3446 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
3447 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
3448 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
3449 */
3450 if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
3451 bio_op(bio) == REQ_OP_DISCARD)) {
3452 bio_set_dev(bio, cc->dev->bdev);
3453 if (bio_sectors(bio))
3454 bio->bi_iter.bi_sector = cc->start +
3455 dm_target_offset(ti, bio->bi_iter.bi_sector);
3456 return DM_MAPIO_REMAPPED;
3457 }
3458
3459 /*
3460 * Check if bio is too large, split as needed.
3461 */
3462 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) &&
3463 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
3464 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT));
3465
3466 /*
3467 * Ensure that bio is a multiple of internal sector encryption size
3468 * and is aligned to this size as defined in IO hints.
3469 */
3470 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
3471 return DM_MAPIO_KILL;
3472
3473 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
3474 return DM_MAPIO_KILL;
3475
3476 io = dm_per_bio_data(bio, cc->per_bio_data_size);
3477 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
3478
3479 if (cc->on_disk_tag_size) {
3480 unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
3481
3482 if (unlikely(tag_len > KMALLOC_MAX_SIZE))
3483 io->integrity_metadata = NULL;
3484 else
3485 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
3486
3487 if (unlikely(!io->integrity_metadata)) {
3488 if (bio_sectors(bio) > cc->tag_pool_max_sectors)
3489 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
3490 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
3491 io->integrity_metadata_from_pool = true;
3492 }
3493 }
3494
3495 if (crypt_integrity_aead(cc))
3496 io->ctx.r.req_aead = (struct aead_request *)(io + 1);
3497 else
3498 io->ctx.r.req = (struct skcipher_request *)(io + 1);
3499
3500 if (bio_data_dir(io->base_bio) == READ) {
3501 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP))
3502 kcryptd_queue_read(io);
3503 } else
3504 kcryptd_queue_crypt(io);
3505
3506 return DM_MAPIO_SUBMITTED;
3507}
3508
3509static char hex2asc(unsigned char c)
3510{
3511 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27);
3512}
3513
3514static void crypt_status(struct dm_target *ti, status_type_t type,
3515 unsigned int status_flags, char *result, unsigned int maxlen)
3516{
3517 struct crypt_config *cc = ti->private;
3518 unsigned int i, sz = 0;
3519 int num_feature_args = 0;
3520
3521 switch (type) {
3522 case STATUSTYPE_INFO:
3523 result[0] = '\0';
3524 break;
3525
3526 case STATUSTYPE_TABLE:
3527 DMEMIT("%s ", cc->cipher_string);
3528
3529 if (cc->key_size > 0) {
3530 if (cc->key_string)
3531 DMEMIT(":%u:%s", cc->key_size, cc->key_string);
3532 else {
3533 for (i = 0; i < cc->key_size; i++) {
3534 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4),
3535 hex2asc(cc->key[i] & 0xf));
3536 }
3537 }
3538 } else
3539 DMEMIT("-");
3540
3541 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
3542 cc->dev->name, (unsigned long long)cc->start);
3543
3544 num_feature_args += !!ti->num_discard_bios;
3545 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3546 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3547 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3548 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3549 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
3550 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3551 if (cc->on_disk_tag_size)
3552 num_feature_args++;
3553 if (num_feature_args) {
3554 DMEMIT(" %d", num_feature_args);
3555 if (ti->num_discard_bios)
3556 DMEMIT(" allow_discards");
3557 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3558 DMEMIT(" same_cpu_crypt");
3559 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
3560 DMEMIT(" submit_from_crypt_cpus");
3561 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
3562 DMEMIT(" no_read_workqueue");
3563 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
3564 DMEMIT(" no_write_workqueue");
3565 if (cc->on_disk_tag_size)
3566 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
3567 if (cc->sector_size != (1 << SECTOR_SHIFT))
3568 DMEMIT(" sector_size:%d", cc->sector_size);
3569 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
3570 DMEMIT(" iv_large_sectors");
3571 }
3572 break;
3573
3574 case STATUSTYPE_IMA:
3575 DMEMIT_TARGET_NAME_VERSION(ti->type);
3576 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n');
3577 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n');
3578 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ?
3579 'y' : 'n');
3580 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ?
3581 'y' : 'n');
3582 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ?
3583 'y' : 'n');
3584 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ?
3585 'y' : 'n');
3586
3587 if (cc->on_disk_tag_size)
3588 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s",
3589 cc->on_disk_tag_size, cc->cipher_auth);
3590 if (cc->sector_size != (1 << SECTOR_SHIFT))
3591 DMEMIT(",sector_size=%d", cc->sector_size);
3592 if (cc->cipher_string)
3593 DMEMIT(",cipher_string=%s", cc->cipher_string);
3594
3595 DMEMIT(",key_size=%u", cc->key_size);
3596 DMEMIT(",key_parts=%u", cc->key_parts);
3597 DMEMIT(",key_extra_size=%u", cc->key_extra_size);
3598 DMEMIT(",key_mac_size=%u", cc->key_mac_size);
3599 DMEMIT(";");
3600 break;
3601 }
3602}
3603
3604static void crypt_postsuspend(struct dm_target *ti)
3605{
3606 struct crypt_config *cc = ti->private;
3607
3608 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3609}
3610
3611static int crypt_preresume(struct dm_target *ti)
3612{
3613 struct crypt_config *cc = ti->private;
3614
3615 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
3616 DMERR("aborting resume - crypt key is not set.");
3617 return -EAGAIN;
3618 }
3619
3620 return 0;
3621}
3622
3623static void crypt_resume(struct dm_target *ti)
3624{
3625 struct crypt_config *cc = ti->private;
3626
3627 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3628}
3629
3630/* Message interface
3631 * key set <key>
3632 * key wipe
3633 */
3634static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv,
3635 char *result, unsigned int maxlen)
3636{
3637 struct crypt_config *cc = ti->private;
3638 int key_size, ret = -EINVAL;
3639
3640 if (argc < 2)
3641 goto error;
3642
3643 if (!strcasecmp(argv[0], "key")) {
3644 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
3645 DMWARN("not suspended during key manipulation.");
3646 return -EINVAL;
3647 }
3648 if (argc == 3 && !strcasecmp(argv[1], "set")) {
3649 /* The key size may not be changed. */
3650 key_size = get_key_size(&argv[2]);
3651 if (key_size < 0 || cc->key_size != key_size) {
3652 memset(argv[2], '0', strlen(argv[2]));
3653 return -EINVAL;
3654 }
3655
3656 ret = crypt_set_key(cc, argv[2]);
3657 if (ret)
3658 return ret;
3659 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
3660 ret = cc->iv_gen_ops->init(cc);
3661 /* wipe the kernel key payload copy */
3662 if (cc->key_string)
3663 memset(cc->key, 0, cc->key_size * sizeof(u8));
3664 return ret;
3665 }
3666 if (argc == 2 && !strcasecmp(argv[1], "wipe"))
3667 return crypt_wipe_key(cc);
3668 }
3669
3670error:
3671 DMWARN("unrecognised message received.");
3672 return -EINVAL;
3673}
3674
3675static int crypt_iterate_devices(struct dm_target *ti,
3676 iterate_devices_callout_fn fn, void *data)
3677{
3678 struct crypt_config *cc = ti->private;
3679
3680 return fn(ti, cc->dev, cc->start, ti->len, data);
3681}
3682
3683static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
3684{
3685 struct crypt_config *cc = ti->private;
3686
3687 /*
3688 * Unfortunate constraint that is required to avoid the potential
3689 * for exceeding underlying device's max_segments limits -- due to
3690 * crypt_alloc_buffer() possibly allocating pages for the encryption
3691 * bio that are not as physically contiguous as the original bio.
3692 */
3693 limits->max_segment_size = PAGE_SIZE;
3694
3695 limits->logical_block_size =
3696 max_t(unsigned int, limits->logical_block_size, cc->sector_size);
3697 limits->physical_block_size =
3698 max_t(unsigned int, limits->physical_block_size, cc->sector_size);
3699 limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size);
3700 limits->dma_alignment = limits->logical_block_size - 1;
3701}
3702
3703static struct target_type crypt_target = {
3704 .name = "crypt",
3705 .version = {1, 25, 0},
3706 .module = THIS_MODULE,
3707 .ctr = crypt_ctr,
3708 .dtr = crypt_dtr,
3709 .features = DM_TARGET_ZONED_HM,
3710 .report_zones = crypt_report_zones,
3711 .map = crypt_map,
3712 .status = crypt_status,
3713 .postsuspend = crypt_postsuspend,
3714 .preresume = crypt_preresume,
3715 .resume = crypt_resume,
3716 .message = crypt_message,
3717 .iterate_devices = crypt_iterate_devices,
3718 .io_hints = crypt_io_hints,
3719};
3720module_dm(crypt);
3721
3722MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3723MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3724MODULE_LICENSE("GPL");
1/*
2 * Copyright (C) 2003 Jana Saout <jana@saout.de>
3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
4 * Copyright (C) 2006-2020 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/blk-integrity.h>
19#include <linux/mempool.h>
20#include <linux/slab.h>
21#include <linux/crypto.h>
22#include <linux/workqueue.h>
23#include <linux/kthread.h>
24#include <linux/backing-dev.h>
25#include <linux/atomic.h>
26#include <linux/scatterlist.h>
27#include <linux/rbtree.h>
28#include <linux/ctype.h>
29#include <asm/page.h>
30#include <asm/unaligned.h>
31#include <crypto/hash.h>
32#include <crypto/md5.h>
33#include <crypto/algapi.h>
34#include <crypto/skcipher.h>
35#include <crypto/aead.h>
36#include <crypto/authenc.h>
37#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
38#include <linux/key-type.h>
39#include <keys/user-type.h>
40#include <keys/encrypted-type.h>
41#include <keys/trusted-type.h>
42
43#include <linux/device-mapper.h>
44
45#include "dm-audit.h"
46
47#define DM_MSG_PREFIX "crypt"
48
49/*
50 * context holding the current state of a multi-part conversion
51 */
52struct convert_context {
53 struct completion restart;
54 struct bio *bio_in;
55 struct bio *bio_out;
56 struct bvec_iter iter_in;
57 struct bvec_iter iter_out;
58 u64 cc_sector;
59 atomic_t cc_pending;
60 union {
61 struct skcipher_request *req;
62 struct aead_request *req_aead;
63 } r;
64
65};
66
67/*
68 * per bio private data
69 */
70struct dm_crypt_io {
71 struct crypt_config *cc;
72 struct bio *base_bio;
73 u8 *integrity_metadata;
74 bool integrity_metadata_from_pool;
75 struct work_struct work;
76 struct tasklet_struct tasklet;
77
78 struct convert_context ctx;
79
80 atomic_t io_pending;
81 blk_status_t error;
82 sector_t sector;
83
84 struct rb_node rb_node;
85} CRYPTO_MINALIGN_ATTR;
86
87struct dm_crypt_request {
88 struct convert_context *ctx;
89 struct scatterlist sg_in[4];
90 struct scatterlist sg_out[4];
91 u64 iv_sector;
92};
93
94struct crypt_config;
95
96struct crypt_iv_operations {
97 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
98 const char *opts);
99 void (*dtr)(struct crypt_config *cc);
100 int (*init)(struct crypt_config *cc);
101 int (*wipe)(struct crypt_config *cc);
102 int (*generator)(struct crypt_config *cc, u8 *iv,
103 struct dm_crypt_request *dmreq);
104 int (*post)(struct crypt_config *cc, u8 *iv,
105 struct dm_crypt_request *dmreq);
106};
107
108struct iv_benbi_private {
109 int shift;
110};
111
112#define LMK_SEED_SIZE 64 /* hash + 0 */
113struct iv_lmk_private {
114 struct crypto_shash *hash_tfm;
115 u8 *seed;
116};
117
118#define TCW_WHITENING_SIZE 16
119struct iv_tcw_private {
120 struct crypto_shash *crc32_tfm;
121 u8 *iv_seed;
122 u8 *whitening;
123};
124
125#define ELEPHANT_MAX_KEY_SIZE 32
126struct iv_elephant_private {
127 struct crypto_skcipher *tfm;
128};
129
130/*
131 * Crypt: maps a linear range of a block device
132 * and encrypts / decrypts at the same time.
133 */
134enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
135 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD,
136 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE,
137 DM_CRYPT_WRITE_INLINE };
138
139enum cipher_flags {
140 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */
141 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */
142 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */
143};
144
145/*
146 * The fields in here must be read only after initialization.
147 */
148struct crypt_config {
149 struct dm_dev *dev;
150 sector_t start;
151
152 struct percpu_counter n_allocated_pages;
153
154 struct workqueue_struct *io_queue;
155 struct workqueue_struct *crypt_queue;
156
157 spinlock_t write_thread_lock;
158 struct task_struct *write_thread;
159 struct rb_root write_tree;
160
161 char *cipher_string;
162 char *cipher_auth;
163 char *key_string;
164
165 const struct crypt_iv_operations *iv_gen_ops;
166 union {
167 struct iv_benbi_private benbi;
168 struct iv_lmk_private lmk;
169 struct iv_tcw_private tcw;
170 struct iv_elephant_private elephant;
171 } iv_gen_private;
172 u64 iv_offset;
173 unsigned int iv_size;
174 unsigned short int sector_size;
175 unsigned char sector_shift;
176
177 union {
178 struct crypto_skcipher **tfms;
179 struct crypto_aead **tfms_aead;
180 } cipher_tfm;
181 unsigned tfms_count;
182 unsigned long cipher_flags;
183
184 /*
185 * Layout of each crypto request:
186 *
187 * struct skcipher_request
188 * context
189 * padding
190 * struct dm_crypt_request
191 * padding
192 * IV
193 *
194 * The padding is added so that dm_crypt_request and the IV are
195 * correctly aligned.
196 */
197 unsigned int dmreq_start;
198
199 unsigned int per_bio_data_size;
200
201 unsigned long flags;
202 unsigned int key_size;
203 unsigned int key_parts; /* independent parts in key buffer */
204 unsigned int key_extra_size; /* additional keys length */
205 unsigned int key_mac_size; /* MAC key size for authenc(...) */
206
207 unsigned int integrity_tag_size;
208 unsigned int integrity_iv_size;
209 unsigned int on_disk_tag_size;
210
211 /*
212 * pool for per bio private data, crypto requests,
213 * encryption requeusts/buffer pages and integrity tags
214 */
215 unsigned tag_pool_max_sectors;
216 mempool_t tag_pool;
217 mempool_t req_pool;
218 mempool_t page_pool;
219
220 struct bio_set bs;
221 struct mutex bio_alloc_lock;
222
223 u8 *authenc_key; /* space for keys in authenc() format (if used) */
224 u8 key[];
225};
226
227#define MIN_IOS 64
228#define MAX_TAG_SIZE 480
229#define POOL_ENTRY_SIZE 512
230
231static DEFINE_SPINLOCK(dm_crypt_clients_lock);
232static unsigned dm_crypt_clients_n = 0;
233static volatile unsigned long dm_crypt_pages_per_client;
234#define DM_CRYPT_MEMORY_PERCENT 2
235#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16)
236
237static void crypt_endio(struct bio *clone);
238static void kcryptd_queue_crypt(struct dm_crypt_io *io);
239static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
240 struct scatterlist *sg);
241
242static bool crypt_integrity_aead(struct crypt_config *cc);
243
244/*
245 * Use this to access cipher attributes that are independent of the key.
246 */
247static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
248{
249 return cc->cipher_tfm.tfms[0];
250}
251
252static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
253{
254 return cc->cipher_tfm.tfms_aead[0];
255}
256
257/*
258 * Different IV generation algorithms:
259 *
260 * plain: the initial vector is the 32-bit little-endian version of the sector
261 * number, padded with zeros if necessary.
262 *
263 * plain64: the initial vector is the 64-bit little-endian version of the sector
264 * number, padded with zeros if necessary.
265 *
266 * plain64be: the initial vector is the 64-bit big-endian version of the sector
267 * number, padded with zeros if necessary.
268 *
269 * essiv: "encrypted sector|salt initial vector", the sector number is
270 * encrypted with the bulk cipher using a salt as key. The salt
271 * should be derived from the bulk cipher's key via hashing.
272 *
273 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
274 * (needed for LRW-32-AES and possible other narrow block modes)
275 *
276 * null: the initial vector is always zero. Provides compatibility with
277 * obsolete loop_fish2 devices. Do not use for new devices.
278 *
279 * lmk: Compatible implementation of the block chaining mode used
280 * by the Loop-AES block device encryption system
281 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
282 * It operates on full 512 byte sectors and uses CBC
283 * with an IV derived from the sector number, the data and
284 * optionally extra IV seed.
285 * This means that after decryption the first block
286 * of sector must be tweaked according to decrypted data.
287 * Loop-AES can use three encryption schemes:
288 * version 1: is plain aes-cbc mode
289 * version 2: uses 64 multikey scheme with lmk IV generator
290 * version 3: the same as version 2 with additional IV seed
291 * (it uses 65 keys, last key is used as IV seed)
292 *
293 * tcw: Compatible implementation of the block chaining mode used
294 * by the TrueCrypt device encryption system (prior to version 4.1).
295 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
296 * It operates on full 512 byte sectors and uses CBC
297 * with an IV derived from initial key and the sector number.
298 * In addition, whitening value is applied on every sector, whitening
299 * is calculated from initial key, sector number and mixed using CRC32.
300 * Note that this encryption scheme is vulnerable to watermarking attacks
301 * and should be used for old compatible containers access only.
302 *
303 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
304 * The IV is encrypted little-endian byte-offset (with the same key
305 * and cipher as the volume).
306 *
307 * elephant: The extended version of eboiv with additional Elephant diffuser
308 * used with Bitlocker CBC mode.
309 * This mode was used in older Windows systems
310 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
311 */
312
313static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
314 struct dm_crypt_request *dmreq)
315{
316 memset(iv, 0, cc->iv_size);
317 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
318
319 return 0;
320}
321
322static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
323 struct dm_crypt_request *dmreq)
324{
325 memset(iv, 0, cc->iv_size);
326 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
327
328 return 0;
329}
330
331static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
332 struct dm_crypt_request *dmreq)
333{
334 memset(iv, 0, cc->iv_size);
335 /* iv_size is at least of size u64; usually it is 16 bytes */
336 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
337
338 return 0;
339}
340
341static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
342 struct dm_crypt_request *dmreq)
343{
344 /*
345 * ESSIV encryption of the IV is now handled by the crypto API,
346 * so just pass the plain sector number here.
347 */
348 memset(iv, 0, cc->iv_size);
349 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
350
351 return 0;
352}
353
354static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
355 const char *opts)
356{
357 unsigned bs;
358 int log;
359
360 if (crypt_integrity_aead(cc))
361 bs = crypto_aead_blocksize(any_tfm_aead(cc));
362 else
363 bs = crypto_skcipher_blocksize(any_tfm(cc));
364 log = ilog2(bs);
365
366 /* we need to calculate how far we must shift the sector count
367 * to get the cipher block count, we use this shift in _gen */
368
369 if (1 << log != bs) {
370 ti->error = "cypher blocksize is not a power of 2";
371 return -EINVAL;
372 }
373
374 if (log > 9) {
375 ti->error = "cypher blocksize is > 512";
376 return -EINVAL;
377 }
378
379 cc->iv_gen_private.benbi.shift = 9 - log;
380
381 return 0;
382}
383
384static void crypt_iv_benbi_dtr(struct crypt_config *cc)
385{
386}
387
388static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
389 struct dm_crypt_request *dmreq)
390{
391 __be64 val;
392
393 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
394
395 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
396 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
397
398 return 0;
399}
400
401static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
402 struct dm_crypt_request *dmreq)
403{
404 memset(iv, 0, cc->iv_size);
405
406 return 0;
407}
408
409static void crypt_iv_lmk_dtr(struct crypt_config *cc)
410{
411 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
412
413 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
414 crypto_free_shash(lmk->hash_tfm);
415 lmk->hash_tfm = NULL;
416
417 kfree_sensitive(lmk->seed);
418 lmk->seed = NULL;
419}
420
421static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
422 const char *opts)
423{
424 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
425
426 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
427 ti->error = "Unsupported sector size for LMK";
428 return -EINVAL;
429 }
430
431 lmk->hash_tfm = crypto_alloc_shash("md5", 0,
432 CRYPTO_ALG_ALLOCATES_MEMORY);
433 if (IS_ERR(lmk->hash_tfm)) {
434 ti->error = "Error initializing LMK hash";
435 return PTR_ERR(lmk->hash_tfm);
436 }
437
438 /* No seed in LMK version 2 */
439 if (cc->key_parts == cc->tfms_count) {
440 lmk->seed = NULL;
441 return 0;
442 }
443
444 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
445 if (!lmk->seed) {
446 crypt_iv_lmk_dtr(cc);
447 ti->error = "Error kmallocing seed storage in LMK";
448 return -ENOMEM;
449 }
450
451 return 0;
452}
453
454static int crypt_iv_lmk_init(struct crypt_config *cc)
455{
456 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
457 int subkey_size = cc->key_size / cc->key_parts;
458
459 /* LMK seed is on the position of LMK_KEYS + 1 key */
460 if (lmk->seed)
461 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
462 crypto_shash_digestsize(lmk->hash_tfm));
463
464 return 0;
465}
466
467static int crypt_iv_lmk_wipe(struct crypt_config *cc)
468{
469 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
470
471 if (lmk->seed)
472 memset(lmk->seed, 0, LMK_SEED_SIZE);
473
474 return 0;
475}
476
477static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
478 struct dm_crypt_request *dmreq,
479 u8 *data)
480{
481 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
482 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
483 struct md5_state md5state;
484 __le32 buf[4];
485 int i, r;
486
487 desc->tfm = lmk->hash_tfm;
488
489 r = crypto_shash_init(desc);
490 if (r)
491 return r;
492
493 if (lmk->seed) {
494 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
495 if (r)
496 return r;
497 }
498
499 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
500 r = crypto_shash_update(desc, data + 16, 16 * 31);
501 if (r)
502 return r;
503
504 /* Sector is cropped to 56 bits here */
505 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
506 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
507 buf[2] = cpu_to_le32(4024);
508 buf[3] = 0;
509 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
510 if (r)
511 return r;
512
513 /* No MD5 padding here */
514 r = crypto_shash_export(desc, &md5state);
515 if (r)
516 return r;
517
518 for (i = 0; i < MD5_HASH_WORDS; i++)
519 __cpu_to_le32s(&md5state.hash[i]);
520 memcpy(iv, &md5state.hash, cc->iv_size);
521
522 return 0;
523}
524
525static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
526 struct dm_crypt_request *dmreq)
527{
528 struct scatterlist *sg;
529 u8 *src;
530 int r = 0;
531
532 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
533 sg = crypt_get_sg_data(cc, dmreq->sg_in);
534 src = kmap_atomic(sg_page(sg));
535 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
536 kunmap_atomic(src);
537 } else
538 memset(iv, 0, cc->iv_size);
539
540 return r;
541}
542
543static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
544 struct dm_crypt_request *dmreq)
545{
546 struct scatterlist *sg;
547 u8 *dst;
548 int r;
549
550 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
551 return 0;
552
553 sg = crypt_get_sg_data(cc, dmreq->sg_out);
554 dst = kmap_atomic(sg_page(sg));
555 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
556
557 /* Tweak the first block of plaintext sector */
558 if (!r)
559 crypto_xor(dst + sg->offset, iv, cc->iv_size);
560
561 kunmap_atomic(dst);
562 return r;
563}
564
565static void crypt_iv_tcw_dtr(struct crypt_config *cc)
566{
567 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
568
569 kfree_sensitive(tcw->iv_seed);
570 tcw->iv_seed = NULL;
571 kfree_sensitive(tcw->whitening);
572 tcw->whitening = NULL;
573
574 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
575 crypto_free_shash(tcw->crc32_tfm);
576 tcw->crc32_tfm = NULL;
577}
578
579static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
580 const char *opts)
581{
582 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
583
584 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
585 ti->error = "Unsupported sector size for TCW";
586 return -EINVAL;
587 }
588
589 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
590 ti->error = "Wrong key size for TCW";
591 return -EINVAL;
592 }
593
594 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0,
595 CRYPTO_ALG_ALLOCATES_MEMORY);
596 if (IS_ERR(tcw->crc32_tfm)) {
597 ti->error = "Error initializing CRC32 in TCW";
598 return PTR_ERR(tcw->crc32_tfm);
599 }
600
601 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
602 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
603 if (!tcw->iv_seed || !tcw->whitening) {
604 crypt_iv_tcw_dtr(cc);
605 ti->error = "Error allocating seed storage in TCW";
606 return -ENOMEM;
607 }
608
609 return 0;
610}
611
612static int crypt_iv_tcw_init(struct crypt_config *cc)
613{
614 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
615 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
616
617 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
618 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
619 TCW_WHITENING_SIZE);
620
621 return 0;
622}
623
624static int crypt_iv_tcw_wipe(struct crypt_config *cc)
625{
626 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
627
628 memset(tcw->iv_seed, 0, cc->iv_size);
629 memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
630
631 return 0;
632}
633
634static int crypt_iv_tcw_whitening(struct crypt_config *cc,
635 struct dm_crypt_request *dmreq,
636 u8 *data)
637{
638 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
639 __le64 sector = cpu_to_le64(dmreq->iv_sector);
640 u8 buf[TCW_WHITENING_SIZE];
641 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
642 int i, r;
643
644 /* xor whitening with sector number */
645 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8);
646 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8);
647
648 /* calculate crc32 for every 32bit part and xor it */
649 desc->tfm = tcw->crc32_tfm;
650 for (i = 0; i < 4; i++) {
651 r = crypto_shash_init(desc);
652 if (r)
653 goto out;
654 r = crypto_shash_update(desc, &buf[i * 4], 4);
655 if (r)
656 goto out;
657 r = crypto_shash_final(desc, &buf[i * 4]);
658 if (r)
659 goto out;
660 }
661 crypto_xor(&buf[0], &buf[12], 4);
662 crypto_xor(&buf[4], &buf[8], 4);
663
664 /* apply whitening (8 bytes) to whole sector */
665 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
666 crypto_xor(data + i * 8, buf, 8);
667out:
668 memzero_explicit(buf, sizeof(buf));
669 return r;
670}
671
672static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
673 struct dm_crypt_request *dmreq)
674{
675 struct scatterlist *sg;
676 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
677 __le64 sector = cpu_to_le64(dmreq->iv_sector);
678 u8 *src;
679 int r = 0;
680
681 /* Remove whitening from ciphertext */
682 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
683 sg = crypt_get_sg_data(cc, dmreq->sg_in);
684 src = kmap_atomic(sg_page(sg));
685 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
686 kunmap_atomic(src);
687 }
688
689 /* Calculate IV */
690 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8);
691 if (cc->iv_size > 8)
692 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or,
693 cc->iv_size - 8);
694
695 return r;
696}
697
698static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
699 struct dm_crypt_request *dmreq)
700{
701 struct scatterlist *sg;
702 u8 *dst;
703 int r;
704
705 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
706 return 0;
707
708 /* Apply whitening on ciphertext */
709 sg = crypt_get_sg_data(cc, dmreq->sg_out);
710 dst = kmap_atomic(sg_page(sg));
711 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
712 kunmap_atomic(dst);
713
714 return r;
715}
716
717static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
718 struct dm_crypt_request *dmreq)
719{
720 /* Used only for writes, there must be an additional space to store IV */
721 get_random_bytes(iv, cc->iv_size);
722 return 0;
723}
724
725static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
726 const char *opts)
727{
728 if (crypt_integrity_aead(cc)) {
729 ti->error = "AEAD transforms not supported for EBOIV";
730 return -EINVAL;
731 }
732
733 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
734 ti->error = "Block size of EBOIV cipher does "
735 "not match IV size of block cipher";
736 return -EINVAL;
737 }
738
739 return 0;
740}
741
742static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
743 struct dm_crypt_request *dmreq)
744{
745 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64));
746 struct skcipher_request *req;
747 struct scatterlist src, dst;
748 DECLARE_CRYPTO_WAIT(wait);
749 int err;
750
751 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO);
752 if (!req)
753 return -ENOMEM;
754
755 memset(buf, 0, cc->iv_size);
756 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
757
758 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
759 sg_init_one(&dst, iv, cc->iv_size);
760 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
761 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
762 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
763 skcipher_request_free(req);
764
765 return err;
766}
767
768static void crypt_iv_elephant_dtr(struct crypt_config *cc)
769{
770 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
771
772 crypto_free_skcipher(elephant->tfm);
773 elephant->tfm = NULL;
774}
775
776static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
777 const char *opts)
778{
779 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
780 int r;
781
782 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0,
783 CRYPTO_ALG_ALLOCATES_MEMORY);
784 if (IS_ERR(elephant->tfm)) {
785 r = PTR_ERR(elephant->tfm);
786 elephant->tfm = NULL;
787 return r;
788 }
789
790 r = crypt_iv_eboiv_ctr(cc, ti, NULL);
791 if (r)
792 crypt_iv_elephant_dtr(cc);
793 return r;
794}
795
796static void diffuser_disk_to_cpu(u32 *d, size_t n)
797{
798#ifndef __LITTLE_ENDIAN
799 int i;
800
801 for (i = 0; i < n; i++)
802 d[i] = le32_to_cpu((__le32)d[i]);
803#endif
804}
805
806static void diffuser_cpu_to_disk(__le32 *d, size_t n)
807{
808#ifndef __LITTLE_ENDIAN
809 int i;
810
811 for (i = 0; i < n; i++)
812 d[i] = cpu_to_le32((u32)d[i]);
813#endif
814}
815
816static void diffuser_a_decrypt(u32 *d, size_t n)
817{
818 int i, i1, i2, i3;
819
820 for (i = 0; i < 5; i++) {
821 i1 = 0;
822 i2 = n - 2;
823 i3 = n - 5;
824
825 while (i1 < (n - 1)) {
826 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
827 i1++; i2++; i3++;
828
829 if (i3 >= n)
830 i3 -= n;
831
832 d[i1] += d[i2] ^ d[i3];
833 i1++; i2++; i3++;
834
835 if (i2 >= n)
836 i2 -= n;
837
838 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
839 i1++; i2++; i3++;
840
841 d[i1] += d[i2] ^ d[i3];
842 i1++; i2++; i3++;
843 }
844 }
845}
846
847static void diffuser_a_encrypt(u32 *d, size_t n)
848{
849 int i, i1, i2, i3;
850
851 for (i = 0; i < 5; i++) {
852 i1 = n - 1;
853 i2 = n - 2 - 1;
854 i3 = n - 5 - 1;
855
856 while (i1 > 0) {
857 d[i1] -= d[i2] ^ d[i3];
858 i1--; i2--; i3--;
859
860 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
861 i1--; i2--; i3--;
862
863 if (i2 < 0)
864 i2 += n;
865
866 d[i1] -= d[i2] ^ d[i3];
867 i1--; i2--; i3--;
868
869 if (i3 < 0)
870 i3 += n;
871
872 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
873 i1--; i2--; i3--;
874 }
875 }
876}
877
878static void diffuser_b_decrypt(u32 *d, size_t n)
879{
880 int i, i1, i2, i3;
881
882 for (i = 0; i < 3; i++) {
883 i1 = 0;
884 i2 = 2;
885 i3 = 5;
886
887 while (i1 < (n - 1)) {
888 d[i1] += d[i2] ^ d[i3];
889 i1++; i2++; i3++;
890
891 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
892 i1++; i2++; i3++;
893
894 if (i2 >= n)
895 i2 -= n;
896
897 d[i1] += d[i2] ^ d[i3];
898 i1++; i2++; i3++;
899
900 if (i3 >= n)
901 i3 -= n;
902
903 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
904 i1++; i2++; i3++;
905 }
906 }
907}
908
909static void diffuser_b_encrypt(u32 *d, size_t n)
910{
911 int i, i1, i2, i3;
912
913 for (i = 0; i < 3; i++) {
914 i1 = n - 1;
915 i2 = 2 - 1;
916 i3 = 5 - 1;
917
918 while (i1 > 0) {
919 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
920 i1--; i2--; i3--;
921
922 if (i3 < 0)
923 i3 += n;
924
925 d[i1] -= d[i2] ^ d[i3];
926 i1--; i2--; i3--;
927
928 if (i2 < 0)
929 i2 += n;
930
931 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
932 i1--; i2--; i3--;
933
934 d[i1] -= d[i2] ^ d[i3];
935 i1--; i2--; i3--;
936 }
937 }
938}
939
940static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq)
941{
942 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
943 u8 *es, *ks, *data, *data2, *data_offset;
944 struct skcipher_request *req;
945 struct scatterlist *sg, *sg2, src, dst;
946 DECLARE_CRYPTO_WAIT(wait);
947 int i, r;
948
949 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO);
950 es = kzalloc(16, GFP_NOIO); /* Key for AES */
951 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */
952
953 if (!req || !es || !ks) {
954 r = -ENOMEM;
955 goto out;
956 }
957
958 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
959
960 /* E(Ks, e(s)) */
961 sg_init_one(&src, es, 16);
962 sg_init_one(&dst, ks, 16);
963 skcipher_request_set_crypt(req, &src, &dst, 16, NULL);
964 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
965 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
966 if (r)
967 goto out;
968
969 /* E(Ks, e'(s)) */
970 es[15] = 0x80;
971 sg_init_one(&dst, &ks[16], 16);
972 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
973 if (r)
974 goto out;
975
976 sg = crypt_get_sg_data(cc, dmreq->sg_out);
977 data = kmap_atomic(sg_page(sg));
978 data_offset = data + sg->offset;
979
980 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */
981 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
982 sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
983 data2 = kmap_atomic(sg_page(sg2));
984 memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
985 kunmap_atomic(data2);
986 }
987
988 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
989 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
990 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
991 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
992 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
993 }
994
995 for (i = 0; i < (cc->sector_size / 32); i++)
996 crypto_xor(data_offset + i * 32, ks, 32);
997
998 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
999 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
1000 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
1001 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
1002 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
1003 }
1004
1005 kunmap_atomic(data);
1006out:
1007 kfree_sensitive(ks);
1008 kfree_sensitive(es);
1009 skcipher_request_free(req);
1010 return r;
1011}
1012
1013static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
1014 struct dm_crypt_request *dmreq)
1015{
1016 int r;
1017
1018 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1019 r = crypt_iv_elephant(cc, dmreq);
1020 if (r)
1021 return r;
1022 }
1023
1024 return crypt_iv_eboiv_gen(cc, iv, dmreq);
1025}
1026
1027static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
1028 struct dm_crypt_request *dmreq)
1029{
1030 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
1031 return crypt_iv_elephant(cc, dmreq);
1032
1033 return 0;
1034}
1035
1036static int crypt_iv_elephant_init(struct crypt_config *cc)
1037{
1038 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1039 int key_offset = cc->key_size - cc->key_extra_size;
1040
1041 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size);
1042}
1043
1044static int crypt_iv_elephant_wipe(struct crypt_config *cc)
1045{
1046 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1047 u8 key[ELEPHANT_MAX_KEY_SIZE];
1048
1049 memset(key, 0, cc->key_extra_size);
1050 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size);
1051}
1052
1053static const struct crypt_iv_operations crypt_iv_plain_ops = {
1054 .generator = crypt_iv_plain_gen
1055};
1056
1057static const struct crypt_iv_operations crypt_iv_plain64_ops = {
1058 .generator = crypt_iv_plain64_gen
1059};
1060
1061static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
1062 .generator = crypt_iv_plain64be_gen
1063};
1064
1065static const struct crypt_iv_operations crypt_iv_essiv_ops = {
1066 .generator = crypt_iv_essiv_gen
1067};
1068
1069static const struct crypt_iv_operations crypt_iv_benbi_ops = {
1070 .ctr = crypt_iv_benbi_ctr,
1071 .dtr = crypt_iv_benbi_dtr,
1072 .generator = crypt_iv_benbi_gen
1073};
1074
1075static const struct crypt_iv_operations crypt_iv_null_ops = {
1076 .generator = crypt_iv_null_gen
1077};
1078
1079static const struct crypt_iv_operations crypt_iv_lmk_ops = {
1080 .ctr = crypt_iv_lmk_ctr,
1081 .dtr = crypt_iv_lmk_dtr,
1082 .init = crypt_iv_lmk_init,
1083 .wipe = crypt_iv_lmk_wipe,
1084 .generator = crypt_iv_lmk_gen,
1085 .post = crypt_iv_lmk_post
1086};
1087
1088static const struct crypt_iv_operations crypt_iv_tcw_ops = {
1089 .ctr = crypt_iv_tcw_ctr,
1090 .dtr = crypt_iv_tcw_dtr,
1091 .init = crypt_iv_tcw_init,
1092 .wipe = crypt_iv_tcw_wipe,
1093 .generator = crypt_iv_tcw_gen,
1094 .post = crypt_iv_tcw_post
1095};
1096
1097static const struct crypt_iv_operations crypt_iv_random_ops = {
1098 .generator = crypt_iv_random_gen
1099};
1100
1101static const struct crypt_iv_operations crypt_iv_eboiv_ops = {
1102 .ctr = crypt_iv_eboiv_ctr,
1103 .generator = crypt_iv_eboiv_gen
1104};
1105
1106static const struct crypt_iv_operations crypt_iv_elephant_ops = {
1107 .ctr = crypt_iv_elephant_ctr,
1108 .dtr = crypt_iv_elephant_dtr,
1109 .init = crypt_iv_elephant_init,
1110 .wipe = crypt_iv_elephant_wipe,
1111 .generator = crypt_iv_elephant_gen,
1112 .post = crypt_iv_elephant_post
1113};
1114
1115/*
1116 * Integrity extensions
1117 */
1118static bool crypt_integrity_aead(struct crypt_config *cc)
1119{
1120 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
1121}
1122
1123static bool crypt_integrity_hmac(struct crypt_config *cc)
1124{
1125 return crypt_integrity_aead(cc) && cc->key_mac_size;
1126}
1127
1128/* Get sg containing data */
1129static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
1130 struct scatterlist *sg)
1131{
1132 if (unlikely(crypt_integrity_aead(cc)))
1133 return &sg[2];
1134
1135 return sg;
1136}
1137
1138static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
1139{
1140 struct bio_integrity_payload *bip;
1141 unsigned int tag_len;
1142 int ret;
1143
1144 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
1145 return 0;
1146
1147 bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
1148 if (IS_ERR(bip))
1149 return PTR_ERR(bip);
1150
1151 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift);
1152
1153 bip->bip_iter.bi_size = tag_len;
1154 bip->bip_iter.bi_sector = io->cc->start + io->sector;
1155
1156 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
1157 tag_len, offset_in_page(io->integrity_metadata));
1158 if (unlikely(ret != tag_len))
1159 return -ENOMEM;
1160
1161 return 0;
1162}
1163
1164static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
1165{
1166#ifdef CONFIG_BLK_DEV_INTEGRITY
1167 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
1168 struct mapped_device *md = dm_table_get_md(ti->table);
1169
1170 /* From now we require underlying device with our integrity profile */
1171 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
1172 ti->error = "Integrity profile not supported.";
1173 return -EINVAL;
1174 }
1175
1176 if (bi->tag_size != cc->on_disk_tag_size ||
1177 bi->tuple_size != cc->on_disk_tag_size) {
1178 ti->error = "Integrity profile tag size mismatch.";
1179 return -EINVAL;
1180 }
1181 if (1 << bi->interval_exp != cc->sector_size) {
1182 ti->error = "Integrity profile sector size mismatch.";
1183 return -EINVAL;
1184 }
1185
1186 if (crypt_integrity_aead(cc)) {
1187 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
1188 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
1189 cc->integrity_tag_size, cc->integrity_iv_size);
1190
1191 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
1192 ti->error = "Integrity AEAD auth tag size is not supported.";
1193 return -EINVAL;
1194 }
1195 } else if (cc->integrity_iv_size)
1196 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
1197 cc->integrity_iv_size);
1198
1199 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
1200 ti->error = "Not enough space for integrity tag in the profile.";
1201 return -EINVAL;
1202 }
1203
1204 return 0;
1205#else
1206 ti->error = "Integrity profile not supported.";
1207 return -EINVAL;
1208#endif
1209}
1210
1211static void crypt_convert_init(struct crypt_config *cc,
1212 struct convert_context *ctx,
1213 struct bio *bio_out, struct bio *bio_in,
1214 sector_t sector)
1215{
1216 ctx->bio_in = bio_in;
1217 ctx->bio_out = bio_out;
1218 if (bio_in)
1219 ctx->iter_in = bio_in->bi_iter;
1220 if (bio_out)
1221 ctx->iter_out = bio_out->bi_iter;
1222 ctx->cc_sector = sector + cc->iv_offset;
1223 init_completion(&ctx->restart);
1224}
1225
1226static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1227 void *req)
1228{
1229 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1230}
1231
1232static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1233{
1234 return (void *)((char *)dmreq - cc->dmreq_start);
1235}
1236
1237static u8 *iv_of_dmreq(struct crypt_config *cc,
1238 struct dm_crypt_request *dmreq)
1239{
1240 if (crypt_integrity_aead(cc))
1241 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1242 crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1243 else
1244 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1245 crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1246}
1247
1248static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1249 struct dm_crypt_request *dmreq)
1250{
1251 return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1252}
1253
1254static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
1255 struct dm_crypt_request *dmreq)
1256{
1257 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
1258 return (__le64 *) ptr;
1259}
1260
1261static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1262 struct dm_crypt_request *dmreq)
1263{
1264 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1265 cc->iv_size + sizeof(uint64_t);
1266 return (unsigned int*)ptr;
1267}
1268
1269static void *tag_from_dmreq(struct crypt_config *cc,
1270 struct dm_crypt_request *dmreq)
1271{
1272 struct convert_context *ctx = dmreq->ctx;
1273 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1274
1275 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1276 cc->on_disk_tag_size];
1277}
1278
1279static void *iv_tag_from_dmreq(struct crypt_config *cc,
1280 struct dm_crypt_request *dmreq)
1281{
1282 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1283}
1284
1285static int crypt_convert_block_aead(struct crypt_config *cc,
1286 struct convert_context *ctx,
1287 struct aead_request *req,
1288 unsigned int tag_offset)
1289{
1290 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1291 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1292 struct dm_crypt_request *dmreq;
1293 u8 *iv, *org_iv, *tag_iv, *tag;
1294 __le64 *sector;
1295 int r = 0;
1296
1297 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1298
1299 /* Reject unexpected unaligned bio. */
1300 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1301 return -EIO;
1302
1303 dmreq = dmreq_of_req(cc, req);
1304 dmreq->iv_sector = ctx->cc_sector;
1305 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1306 dmreq->iv_sector >>= cc->sector_shift;
1307 dmreq->ctx = ctx;
1308
1309 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1310
1311 sector = org_sector_of_dmreq(cc, dmreq);
1312 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1313
1314 iv = iv_of_dmreq(cc, dmreq);
1315 org_iv = org_iv_of_dmreq(cc, dmreq);
1316 tag = tag_from_dmreq(cc, dmreq);
1317 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1318
1319 /* AEAD request:
1320 * |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1321 * | (authenticated) | (auth+encryption) | |
1322 * | sector_LE | IV | sector in/out | tag in/out |
1323 */
1324 sg_init_table(dmreq->sg_in, 4);
1325 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1326 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1327 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1328 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1329
1330 sg_init_table(dmreq->sg_out, 4);
1331 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1332 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1333 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1334 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1335
1336 if (cc->iv_gen_ops) {
1337 /* For READs use IV stored in integrity metadata */
1338 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1339 memcpy(org_iv, tag_iv, cc->iv_size);
1340 } else {
1341 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1342 if (r < 0)
1343 return r;
1344 /* Store generated IV in integrity metadata */
1345 if (cc->integrity_iv_size)
1346 memcpy(tag_iv, org_iv, cc->iv_size);
1347 }
1348 /* Working copy of IV, to be modified in crypto API */
1349 memcpy(iv, org_iv, cc->iv_size);
1350 }
1351
1352 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1353 if (bio_data_dir(ctx->bio_in) == WRITE) {
1354 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1355 cc->sector_size, iv);
1356 r = crypto_aead_encrypt(req);
1357 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
1358 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1359 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1360 } else {
1361 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1362 cc->sector_size + cc->integrity_tag_size, iv);
1363 r = crypto_aead_decrypt(req);
1364 }
1365
1366 if (r == -EBADMSG) {
1367 sector_t s = le64_to_cpu(*sector);
1368
1369 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
1370 ctx->bio_in->bi_bdev, s);
1371 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
1372 ctx->bio_in, s, 0);
1373 }
1374
1375 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1376 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1377
1378 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1379 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1380
1381 return r;
1382}
1383
1384static int crypt_convert_block_skcipher(struct crypt_config *cc,
1385 struct convert_context *ctx,
1386 struct skcipher_request *req,
1387 unsigned int tag_offset)
1388{
1389 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1390 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1391 struct scatterlist *sg_in, *sg_out;
1392 struct dm_crypt_request *dmreq;
1393 u8 *iv, *org_iv, *tag_iv;
1394 __le64 *sector;
1395 int r = 0;
1396
1397 /* Reject unexpected unaligned bio. */
1398 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1399 return -EIO;
1400
1401 dmreq = dmreq_of_req(cc, req);
1402 dmreq->iv_sector = ctx->cc_sector;
1403 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1404 dmreq->iv_sector >>= cc->sector_shift;
1405 dmreq->ctx = ctx;
1406
1407 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1408
1409 iv = iv_of_dmreq(cc, dmreq);
1410 org_iv = org_iv_of_dmreq(cc, dmreq);
1411 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1412
1413 sector = org_sector_of_dmreq(cc, dmreq);
1414 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1415
1416 /* For skcipher we use only the first sg item */
1417 sg_in = &dmreq->sg_in[0];
1418 sg_out = &dmreq->sg_out[0];
1419
1420 sg_init_table(sg_in, 1);
1421 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1422
1423 sg_init_table(sg_out, 1);
1424 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1425
1426 if (cc->iv_gen_ops) {
1427 /* For READs use IV stored in integrity metadata */
1428 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1429 memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1430 } else {
1431 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1432 if (r < 0)
1433 return r;
1434 /* Data can be already preprocessed in generator */
1435 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
1436 sg_in = sg_out;
1437 /* Store generated IV in integrity metadata */
1438 if (cc->integrity_iv_size)
1439 memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1440 }
1441 /* Working copy of IV, to be modified in crypto API */
1442 memcpy(iv, org_iv, cc->iv_size);
1443 }
1444
1445 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1446
1447 if (bio_data_dir(ctx->bio_in) == WRITE)
1448 r = crypto_skcipher_encrypt(req);
1449 else
1450 r = crypto_skcipher_decrypt(req);
1451
1452 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1453 r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1454
1455 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1456 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1457
1458 return r;
1459}
1460
1461static void kcryptd_async_done(struct crypto_async_request *async_req,
1462 int error);
1463
1464static int crypt_alloc_req_skcipher(struct crypt_config *cc,
1465 struct convert_context *ctx)
1466{
1467 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
1468
1469 if (!ctx->r.req) {
1470 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1471 if (!ctx->r.req)
1472 return -ENOMEM;
1473 }
1474
1475 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1476
1477 /*
1478 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1479 * requests if driver request queue is full.
1480 */
1481 skcipher_request_set_callback(ctx->r.req,
1482 CRYPTO_TFM_REQ_MAY_BACKLOG,
1483 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
1484
1485 return 0;
1486}
1487
1488static int crypt_alloc_req_aead(struct crypt_config *cc,
1489 struct convert_context *ctx)
1490{
1491 if (!ctx->r.req_aead) {
1492 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1493 if (!ctx->r.req_aead)
1494 return -ENOMEM;
1495 }
1496
1497 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1498
1499 /*
1500 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1501 * requests if driver request queue is full.
1502 */
1503 aead_request_set_callback(ctx->r.req_aead,
1504 CRYPTO_TFM_REQ_MAY_BACKLOG,
1505 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
1506
1507 return 0;
1508}
1509
1510static int crypt_alloc_req(struct crypt_config *cc,
1511 struct convert_context *ctx)
1512{
1513 if (crypt_integrity_aead(cc))
1514 return crypt_alloc_req_aead(cc, ctx);
1515 else
1516 return crypt_alloc_req_skcipher(cc, ctx);
1517}
1518
1519static void crypt_free_req_skcipher(struct crypt_config *cc,
1520 struct skcipher_request *req, struct bio *base_bio)
1521{
1522 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1523
1524 if ((struct skcipher_request *)(io + 1) != req)
1525 mempool_free(req, &cc->req_pool);
1526}
1527
1528static void crypt_free_req_aead(struct crypt_config *cc,
1529 struct aead_request *req, struct bio *base_bio)
1530{
1531 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1532
1533 if ((struct aead_request *)(io + 1) != req)
1534 mempool_free(req, &cc->req_pool);
1535}
1536
1537static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1538{
1539 if (crypt_integrity_aead(cc))
1540 crypt_free_req_aead(cc, req, base_bio);
1541 else
1542 crypt_free_req_skcipher(cc, req, base_bio);
1543}
1544
1545/*
1546 * Encrypt / decrypt data from one bio to another one (can be the same one)
1547 */
1548static blk_status_t crypt_convert(struct crypt_config *cc,
1549 struct convert_context *ctx, bool atomic, bool reset_pending)
1550{
1551 unsigned int tag_offset = 0;
1552 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1553 int r;
1554
1555 /*
1556 * if reset_pending is set we are dealing with the bio for the first time,
1557 * else we're continuing to work on the previous bio, so don't mess with
1558 * the cc_pending counter
1559 */
1560 if (reset_pending)
1561 atomic_set(&ctx->cc_pending, 1);
1562
1563 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1564
1565 r = crypt_alloc_req(cc, ctx);
1566 if (r) {
1567 complete(&ctx->restart);
1568 return BLK_STS_DEV_RESOURCE;
1569 }
1570
1571 atomic_inc(&ctx->cc_pending);
1572
1573 if (crypt_integrity_aead(cc))
1574 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
1575 else
1576 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
1577
1578 switch (r) {
1579 /*
1580 * The request was queued by a crypto driver
1581 * but the driver request queue is full, let's wait.
1582 */
1583 case -EBUSY:
1584 if (in_interrupt()) {
1585 if (try_wait_for_completion(&ctx->restart)) {
1586 /*
1587 * we don't have to block to wait for completion,
1588 * so proceed
1589 */
1590 } else {
1591 /*
1592 * we can't wait for completion without blocking
1593 * exit and continue processing in a workqueue
1594 */
1595 ctx->r.req = NULL;
1596 ctx->cc_sector += sector_step;
1597 tag_offset++;
1598 return BLK_STS_DEV_RESOURCE;
1599 }
1600 } else {
1601 wait_for_completion(&ctx->restart);
1602 }
1603 reinit_completion(&ctx->restart);
1604 fallthrough;
1605 /*
1606 * The request is queued and processed asynchronously,
1607 * completion function kcryptd_async_done() will be called.
1608 */
1609 case -EINPROGRESS:
1610 ctx->r.req = NULL;
1611 ctx->cc_sector += sector_step;
1612 tag_offset++;
1613 continue;
1614 /*
1615 * The request was already processed (synchronously).
1616 */
1617 case 0:
1618 atomic_dec(&ctx->cc_pending);
1619 ctx->cc_sector += sector_step;
1620 tag_offset++;
1621 if (!atomic)
1622 cond_resched();
1623 continue;
1624 /*
1625 * There was a data integrity error.
1626 */
1627 case -EBADMSG:
1628 atomic_dec(&ctx->cc_pending);
1629 return BLK_STS_PROTECTION;
1630 /*
1631 * There was an error while processing the request.
1632 */
1633 default:
1634 atomic_dec(&ctx->cc_pending);
1635 return BLK_STS_IOERR;
1636 }
1637 }
1638
1639 return 0;
1640}
1641
1642static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1643
1644/*
1645 * Generate a new unfragmented bio with the given size
1646 * This should never violate the device limitations (but only because
1647 * max_segment_size is being constrained to PAGE_SIZE).
1648 *
1649 * This function may be called concurrently. If we allocate from the mempool
1650 * concurrently, there is a possibility of deadlock. For example, if we have
1651 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1652 * the mempool concurrently, it may deadlock in a situation where both processes
1653 * have allocated 128 pages and the mempool is exhausted.
1654 *
1655 * In order to avoid this scenario we allocate the pages under a mutex.
1656 *
1657 * In order to not degrade performance with excessive locking, we try
1658 * non-blocking allocations without a mutex first but on failure we fallback
1659 * to blocking allocations with a mutex.
1660 */
1661static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
1662{
1663 struct crypt_config *cc = io->cc;
1664 struct bio *clone;
1665 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1666 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1667 unsigned i, len, remaining_size;
1668 struct page *page;
1669
1670retry:
1671 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1672 mutex_lock(&cc->bio_alloc_lock);
1673
1674 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf,
1675 GFP_NOIO, &cc->bs);
1676 clone->bi_private = io;
1677 clone->bi_end_io = crypt_endio;
1678
1679 remaining_size = size;
1680
1681 for (i = 0; i < nr_iovecs; i++) {
1682 page = mempool_alloc(&cc->page_pool, gfp_mask);
1683 if (!page) {
1684 crypt_free_buffer_pages(cc, clone);
1685 bio_put(clone);
1686 gfp_mask |= __GFP_DIRECT_RECLAIM;
1687 goto retry;
1688 }
1689
1690 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
1691
1692 bio_add_page(clone, page, len, 0);
1693
1694 remaining_size -= len;
1695 }
1696
1697 /* Allocate space for integrity tags */
1698 if (dm_crypt_integrity_io_alloc(io, clone)) {
1699 crypt_free_buffer_pages(cc, clone);
1700 bio_put(clone);
1701 clone = NULL;
1702 }
1703
1704 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1705 mutex_unlock(&cc->bio_alloc_lock);
1706
1707 return clone;
1708}
1709
1710static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1711{
1712 struct bio_vec *bv;
1713 struct bvec_iter_all iter_all;
1714
1715 bio_for_each_segment_all(bv, clone, iter_all) {
1716 BUG_ON(!bv->bv_page);
1717 mempool_free(bv->bv_page, &cc->page_pool);
1718 }
1719}
1720
1721static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1722 struct bio *bio, sector_t sector)
1723{
1724 io->cc = cc;
1725 io->base_bio = bio;
1726 io->sector = sector;
1727 io->error = 0;
1728 io->ctx.r.req = NULL;
1729 io->integrity_metadata = NULL;
1730 io->integrity_metadata_from_pool = false;
1731 atomic_set(&io->io_pending, 0);
1732}
1733
1734static void crypt_inc_pending(struct dm_crypt_io *io)
1735{
1736 atomic_inc(&io->io_pending);
1737}
1738
1739static void kcryptd_io_bio_endio(struct work_struct *work)
1740{
1741 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1742 bio_endio(io->base_bio);
1743}
1744
1745/*
1746 * One of the bios was finished. Check for completion of
1747 * the whole request and correctly clean up the buffer.
1748 */
1749static void crypt_dec_pending(struct dm_crypt_io *io)
1750{
1751 struct crypt_config *cc = io->cc;
1752 struct bio *base_bio = io->base_bio;
1753 blk_status_t error = io->error;
1754
1755 if (!atomic_dec_and_test(&io->io_pending))
1756 return;
1757
1758 if (io->ctx.r.req)
1759 crypt_free_req(cc, io->ctx.r.req, base_bio);
1760
1761 if (unlikely(io->integrity_metadata_from_pool))
1762 mempool_free(io->integrity_metadata, &io->cc->tag_pool);
1763 else
1764 kfree(io->integrity_metadata);
1765
1766 base_bio->bi_status = error;
1767
1768 /*
1769 * If we are running this function from our tasklet,
1770 * we can't call bio_endio() here, because it will call
1771 * clone_endio() from dm.c, which in turn will
1772 * free the current struct dm_crypt_io structure with
1773 * our tasklet. In this case we need to delay bio_endio()
1774 * execution to after the tasklet is done and dequeued.
1775 */
1776 if (tasklet_trylock(&io->tasklet)) {
1777 tasklet_unlock(&io->tasklet);
1778 bio_endio(base_bio);
1779 return;
1780 }
1781
1782 INIT_WORK(&io->work, kcryptd_io_bio_endio);
1783 queue_work(cc->io_queue, &io->work);
1784}
1785
1786/*
1787 * kcryptd/kcryptd_io:
1788 *
1789 * Needed because it would be very unwise to do decryption in an
1790 * interrupt context.
1791 *
1792 * kcryptd performs the actual encryption or decryption.
1793 *
1794 * kcryptd_io performs the IO submission.
1795 *
1796 * They must be separated as otherwise the final stages could be
1797 * starved by new requests which can block in the first stages due
1798 * to memory allocation.
1799 *
1800 * The work is done per CPU global for all dm-crypt instances.
1801 * They should not depend on each other and do not block.
1802 */
1803static void crypt_endio(struct bio *clone)
1804{
1805 struct dm_crypt_io *io = clone->bi_private;
1806 struct crypt_config *cc = io->cc;
1807 unsigned rw = bio_data_dir(clone);
1808 blk_status_t error;
1809
1810 /*
1811 * free the processed pages
1812 */
1813 if (rw == WRITE)
1814 crypt_free_buffer_pages(cc, clone);
1815
1816 error = clone->bi_status;
1817 bio_put(clone);
1818
1819 if (rw == READ && !error) {
1820 kcryptd_queue_crypt(io);
1821 return;
1822 }
1823
1824 if (unlikely(error))
1825 io->error = error;
1826
1827 crypt_dec_pending(io);
1828}
1829
1830#define CRYPT_MAP_READ_GFP GFP_NOWAIT
1831
1832static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1833{
1834 struct crypt_config *cc = io->cc;
1835 struct bio *clone;
1836
1837 /*
1838 * We need the original biovec array in order to decrypt the whole bio
1839 * data *afterwards* -- thanks to immutable biovecs we don't need to
1840 * worry about the block layer modifying the biovec array; so leverage
1841 * bio_alloc_clone().
1842 */
1843 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs);
1844 if (!clone)
1845 return 1;
1846 clone->bi_private = io;
1847 clone->bi_end_io = crypt_endio;
1848
1849 crypt_inc_pending(io);
1850
1851 clone->bi_iter.bi_sector = cc->start + io->sector;
1852
1853 if (dm_crypt_integrity_io_alloc(io, clone)) {
1854 crypt_dec_pending(io);
1855 bio_put(clone);
1856 return 1;
1857 }
1858
1859 dm_submit_bio_remap(io->base_bio, clone);
1860 return 0;
1861}
1862
1863static void kcryptd_io_read_work(struct work_struct *work)
1864{
1865 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1866
1867 crypt_inc_pending(io);
1868 if (kcryptd_io_read(io, GFP_NOIO))
1869 io->error = BLK_STS_RESOURCE;
1870 crypt_dec_pending(io);
1871}
1872
1873static void kcryptd_queue_read(struct dm_crypt_io *io)
1874{
1875 struct crypt_config *cc = io->cc;
1876
1877 INIT_WORK(&io->work, kcryptd_io_read_work);
1878 queue_work(cc->io_queue, &io->work);
1879}
1880
1881static void kcryptd_io_write(struct dm_crypt_io *io)
1882{
1883 struct bio *clone = io->ctx.bio_out;
1884
1885 dm_submit_bio_remap(io->base_bio, clone);
1886}
1887
1888#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1889
1890static int dmcrypt_write(void *data)
1891{
1892 struct crypt_config *cc = data;
1893 struct dm_crypt_io *io;
1894
1895 while (1) {
1896 struct rb_root write_tree;
1897 struct blk_plug plug;
1898
1899 spin_lock_irq(&cc->write_thread_lock);
1900continue_locked:
1901
1902 if (!RB_EMPTY_ROOT(&cc->write_tree))
1903 goto pop_from_list;
1904
1905 set_current_state(TASK_INTERRUPTIBLE);
1906
1907 spin_unlock_irq(&cc->write_thread_lock);
1908
1909 if (unlikely(kthread_should_stop())) {
1910 set_current_state(TASK_RUNNING);
1911 break;
1912 }
1913
1914 schedule();
1915
1916 set_current_state(TASK_RUNNING);
1917 spin_lock_irq(&cc->write_thread_lock);
1918 goto continue_locked;
1919
1920pop_from_list:
1921 write_tree = cc->write_tree;
1922 cc->write_tree = RB_ROOT;
1923 spin_unlock_irq(&cc->write_thread_lock);
1924
1925 BUG_ON(rb_parent(write_tree.rb_node));
1926
1927 /*
1928 * Note: we cannot walk the tree here with rb_next because
1929 * the structures may be freed when kcryptd_io_write is called.
1930 */
1931 blk_start_plug(&plug);
1932 do {
1933 io = crypt_io_from_node(rb_first(&write_tree));
1934 rb_erase(&io->rb_node, &write_tree);
1935 kcryptd_io_write(io);
1936 } while (!RB_EMPTY_ROOT(&write_tree));
1937 blk_finish_plug(&plug);
1938 }
1939 return 0;
1940}
1941
1942static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1943{
1944 struct bio *clone = io->ctx.bio_out;
1945 struct crypt_config *cc = io->cc;
1946 unsigned long flags;
1947 sector_t sector;
1948 struct rb_node **rbp, *parent;
1949
1950 if (unlikely(io->error)) {
1951 crypt_free_buffer_pages(cc, clone);
1952 bio_put(clone);
1953 crypt_dec_pending(io);
1954 return;
1955 }
1956
1957 /* crypt_convert should have filled the clone bio */
1958 BUG_ON(io->ctx.iter_out.bi_size);
1959
1960 clone->bi_iter.bi_sector = cc->start + io->sector;
1961
1962 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
1963 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
1964 dm_submit_bio_remap(io->base_bio, clone);
1965 return;
1966 }
1967
1968 spin_lock_irqsave(&cc->write_thread_lock, flags);
1969 if (RB_EMPTY_ROOT(&cc->write_tree))
1970 wake_up_process(cc->write_thread);
1971 rbp = &cc->write_tree.rb_node;
1972 parent = NULL;
1973 sector = io->sector;
1974 while (*rbp) {
1975 parent = *rbp;
1976 if (sector < crypt_io_from_node(parent)->sector)
1977 rbp = &(*rbp)->rb_left;
1978 else
1979 rbp = &(*rbp)->rb_right;
1980 }
1981 rb_link_node(&io->rb_node, parent, rbp);
1982 rb_insert_color(&io->rb_node, &cc->write_tree);
1983 spin_unlock_irqrestore(&cc->write_thread_lock, flags);
1984}
1985
1986static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
1987 struct convert_context *ctx)
1988
1989{
1990 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
1991 return false;
1992
1993 /*
1994 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
1995 * constraints so they do not need to be issued inline by
1996 * kcryptd_crypt_write_convert().
1997 */
1998 switch (bio_op(ctx->bio_in)) {
1999 case REQ_OP_WRITE:
2000 case REQ_OP_WRITE_ZEROES:
2001 return true;
2002 default:
2003 return false;
2004 }
2005}
2006
2007static void kcryptd_crypt_write_continue(struct work_struct *work)
2008{
2009 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2010 struct crypt_config *cc = io->cc;
2011 struct convert_context *ctx = &io->ctx;
2012 int crypt_finished;
2013 sector_t sector = io->sector;
2014 blk_status_t r;
2015
2016 wait_for_completion(&ctx->restart);
2017 reinit_completion(&ctx->restart);
2018
2019 r = crypt_convert(cc, &io->ctx, true, false);
2020 if (r)
2021 io->error = r;
2022 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2023 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2024 /* Wait for completion signaled by kcryptd_async_done() */
2025 wait_for_completion(&ctx->restart);
2026 crypt_finished = 1;
2027 }
2028
2029 /* Encryption was already finished, submit io now */
2030 if (crypt_finished) {
2031 kcryptd_crypt_write_io_submit(io, 0);
2032 io->sector = sector;
2033 }
2034
2035 crypt_dec_pending(io);
2036}
2037
2038static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
2039{
2040 struct crypt_config *cc = io->cc;
2041 struct convert_context *ctx = &io->ctx;
2042 struct bio *clone;
2043 int crypt_finished;
2044 sector_t sector = io->sector;
2045 blk_status_t r;
2046
2047 /*
2048 * Prevent io from disappearing until this function completes.
2049 */
2050 crypt_inc_pending(io);
2051 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector);
2052
2053 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
2054 if (unlikely(!clone)) {
2055 io->error = BLK_STS_IOERR;
2056 goto dec;
2057 }
2058
2059 io->ctx.bio_out = clone;
2060 io->ctx.iter_out = clone->bi_iter;
2061
2062 sector += bio_sectors(clone);
2063
2064 crypt_inc_pending(io);
2065 r = crypt_convert(cc, ctx,
2066 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true);
2067 /*
2068 * Crypto API backlogged the request, because its queue was full
2069 * and we're in softirq context, so continue from a workqueue
2070 * (TODO: is it actually possible to be in softirq in the write path?)
2071 */
2072 if (r == BLK_STS_DEV_RESOURCE) {
2073 INIT_WORK(&io->work, kcryptd_crypt_write_continue);
2074 queue_work(cc->crypt_queue, &io->work);
2075 return;
2076 }
2077 if (r)
2078 io->error = r;
2079 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2080 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2081 /* Wait for completion signaled by kcryptd_async_done() */
2082 wait_for_completion(&ctx->restart);
2083 crypt_finished = 1;
2084 }
2085
2086 /* Encryption was already finished, submit io now */
2087 if (crypt_finished) {
2088 kcryptd_crypt_write_io_submit(io, 0);
2089 io->sector = sector;
2090 }
2091
2092dec:
2093 crypt_dec_pending(io);
2094}
2095
2096static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
2097{
2098 crypt_dec_pending(io);
2099}
2100
2101static void kcryptd_crypt_read_continue(struct work_struct *work)
2102{
2103 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2104 struct crypt_config *cc = io->cc;
2105 blk_status_t r;
2106
2107 wait_for_completion(&io->ctx.restart);
2108 reinit_completion(&io->ctx.restart);
2109
2110 r = crypt_convert(cc, &io->ctx, true, false);
2111 if (r)
2112 io->error = r;
2113
2114 if (atomic_dec_and_test(&io->ctx.cc_pending))
2115 kcryptd_crypt_read_done(io);
2116
2117 crypt_dec_pending(io);
2118}
2119
2120static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
2121{
2122 struct crypt_config *cc = io->cc;
2123 blk_status_t r;
2124
2125 crypt_inc_pending(io);
2126
2127 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
2128 io->sector);
2129
2130 r = crypt_convert(cc, &io->ctx,
2131 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2132 /*
2133 * Crypto API backlogged the request, because its queue was full
2134 * and we're in softirq context, so continue from a workqueue
2135 */
2136 if (r == BLK_STS_DEV_RESOURCE) {
2137 INIT_WORK(&io->work, kcryptd_crypt_read_continue);
2138 queue_work(cc->crypt_queue, &io->work);
2139 return;
2140 }
2141 if (r)
2142 io->error = r;
2143
2144 if (atomic_dec_and_test(&io->ctx.cc_pending))
2145 kcryptd_crypt_read_done(io);
2146
2147 crypt_dec_pending(io);
2148}
2149
2150static void kcryptd_async_done(struct crypto_async_request *async_req,
2151 int error)
2152{
2153 struct dm_crypt_request *dmreq = async_req->data;
2154 struct convert_context *ctx = dmreq->ctx;
2155 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
2156 struct crypt_config *cc = io->cc;
2157
2158 /*
2159 * A request from crypto driver backlog is going to be processed now,
2160 * finish the completion and continue in crypt_convert().
2161 * (Callback will be called for the second time for this request.)
2162 */
2163 if (error == -EINPROGRESS) {
2164 complete(&ctx->restart);
2165 return;
2166 }
2167
2168 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
2169 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
2170
2171 if (error == -EBADMSG) {
2172 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq));
2173
2174 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
2175 ctx->bio_in->bi_bdev, s);
2176 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
2177 ctx->bio_in, s, 0);
2178 io->error = BLK_STS_PROTECTION;
2179 } else if (error < 0)
2180 io->error = BLK_STS_IOERR;
2181
2182 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
2183
2184 if (!atomic_dec_and_test(&ctx->cc_pending))
2185 return;
2186
2187 /*
2188 * The request is fully completed: for inline writes, let
2189 * kcryptd_crypt_write_convert() do the IO submission.
2190 */
2191 if (bio_data_dir(io->base_bio) == READ) {
2192 kcryptd_crypt_read_done(io);
2193 return;
2194 }
2195
2196 if (kcryptd_crypt_write_inline(cc, ctx)) {
2197 complete(&ctx->restart);
2198 return;
2199 }
2200
2201 kcryptd_crypt_write_io_submit(io, 1);
2202}
2203
2204static void kcryptd_crypt(struct work_struct *work)
2205{
2206 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2207
2208 if (bio_data_dir(io->base_bio) == READ)
2209 kcryptd_crypt_read_convert(io);
2210 else
2211 kcryptd_crypt_write_convert(io);
2212}
2213
2214static void kcryptd_crypt_tasklet(unsigned long work)
2215{
2216 kcryptd_crypt((struct work_struct *)work);
2217}
2218
2219static void kcryptd_queue_crypt(struct dm_crypt_io *io)
2220{
2221 struct crypt_config *cc = io->cc;
2222
2223 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
2224 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
2225 /*
2226 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context.
2227 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but
2228 * it is being executed with irqs disabled.
2229 */
2230 if (in_hardirq() || irqs_disabled()) {
2231 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work);
2232 tasklet_schedule(&io->tasklet);
2233 return;
2234 }
2235
2236 kcryptd_crypt(&io->work);
2237 return;
2238 }
2239
2240 INIT_WORK(&io->work, kcryptd_crypt);
2241 queue_work(cc->crypt_queue, &io->work);
2242}
2243
2244static void crypt_free_tfms_aead(struct crypt_config *cc)
2245{
2246 if (!cc->cipher_tfm.tfms_aead)
2247 return;
2248
2249 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2250 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
2251 cc->cipher_tfm.tfms_aead[0] = NULL;
2252 }
2253
2254 kfree(cc->cipher_tfm.tfms_aead);
2255 cc->cipher_tfm.tfms_aead = NULL;
2256}
2257
2258static void crypt_free_tfms_skcipher(struct crypt_config *cc)
2259{
2260 unsigned i;
2261
2262 if (!cc->cipher_tfm.tfms)
2263 return;
2264
2265 for (i = 0; i < cc->tfms_count; i++)
2266 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
2267 crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
2268 cc->cipher_tfm.tfms[i] = NULL;
2269 }
2270
2271 kfree(cc->cipher_tfm.tfms);
2272 cc->cipher_tfm.tfms = NULL;
2273}
2274
2275static void crypt_free_tfms(struct crypt_config *cc)
2276{
2277 if (crypt_integrity_aead(cc))
2278 crypt_free_tfms_aead(cc);
2279 else
2280 crypt_free_tfms_skcipher(cc);
2281}
2282
2283static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
2284{
2285 unsigned i;
2286 int err;
2287
2288 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count,
2289 sizeof(struct crypto_skcipher *),
2290 GFP_KERNEL);
2291 if (!cc->cipher_tfm.tfms)
2292 return -ENOMEM;
2293
2294 for (i = 0; i < cc->tfms_count; i++) {
2295 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0,
2296 CRYPTO_ALG_ALLOCATES_MEMORY);
2297 if (IS_ERR(cc->cipher_tfm.tfms[i])) {
2298 err = PTR_ERR(cc->cipher_tfm.tfms[i]);
2299 crypt_free_tfms(cc);
2300 return err;
2301 }
2302 }
2303
2304 /*
2305 * dm-crypt performance can vary greatly depending on which crypto
2306 * algorithm implementation is used. Help people debug performance
2307 * problems by logging the ->cra_driver_name.
2308 */
2309 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2310 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
2311 return 0;
2312}
2313
2314static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
2315{
2316 int err;
2317
2318 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
2319 if (!cc->cipher_tfm.tfms)
2320 return -ENOMEM;
2321
2322 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0,
2323 CRYPTO_ALG_ALLOCATES_MEMORY);
2324 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2325 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
2326 crypt_free_tfms(cc);
2327 return err;
2328 }
2329
2330 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2331 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
2332 return 0;
2333}
2334
2335static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
2336{
2337 if (crypt_integrity_aead(cc))
2338 return crypt_alloc_tfms_aead(cc, ciphermode);
2339 else
2340 return crypt_alloc_tfms_skcipher(cc, ciphermode);
2341}
2342
2343static unsigned crypt_subkey_size(struct crypt_config *cc)
2344{
2345 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
2346}
2347
2348static unsigned crypt_authenckey_size(struct crypt_config *cc)
2349{
2350 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
2351}
2352
2353/*
2354 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
2355 * the key must be for some reason in special format.
2356 * This funcion converts cc->key to this special format.
2357 */
2358static void crypt_copy_authenckey(char *p, const void *key,
2359 unsigned enckeylen, unsigned authkeylen)
2360{
2361 struct crypto_authenc_key_param *param;
2362 struct rtattr *rta;
2363
2364 rta = (struct rtattr *)p;
2365 param = RTA_DATA(rta);
2366 param->enckeylen = cpu_to_be32(enckeylen);
2367 rta->rta_len = RTA_LENGTH(sizeof(*param));
2368 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
2369 p += RTA_SPACE(sizeof(*param));
2370 memcpy(p, key + enckeylen, authkeylen);
2371 p += authkeylen;
2372 memcpy(p, key, enckeylen);
2373}
2374
2375static int crypt_setkey(struct crypt_config *cc)
2376{
2377 unsigned subkey_size;
2378 int err = 0, i, r;
2379
2380 /* Ignore extra keys (which are used for IV etc) */
2381 subkey_size = crypt_subkey_size(cc);
2382
2383 if (crypt_integrity_hmac(cc)) {
2384 if (subkey_size < cc->key_mac_size)
2385 return -EINVAL;
2386
2387 crypt_copy_authenckey(cc->authenc_key, cc->key,
2388 subkey_size - cc->key_mac_size,
2389 cc->key_mac_size);
2390 }
2391
2392 for (i = 0; i < cc->tfms_count; i++) {
2393 if (crypt_integrity_hmac(cc))
2394 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2395 cc->authenc_key, crypt_authenckey_size(cc));
2396 else if (crypt_integrity_aead(cc))
2397 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2398 cc->key + (i * subkey_size),
2399 subkey_size);
2400 else
2401 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
2402 cc->key + (i * subkey_size),
2403 subkey_size);
2404 if (r)
2405 err = r;
2406 }
2407
2408 if (crypt_integrity_hmac(cc))
2409 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
2410
2411 return err;
2412}
2413
2414#ifdef CONFIG_KEYS
2415
2416static bool contains_whitespace(const char *str)
2417{
2418 while (*str)
2419 if (isspace(*str++))
2420 return true;
2421 return false;
2422}
2423
2424static int set_key_user(struct crypt_config *cc, struct key *key)
2425{
2426 const struct user_key_payload *ukp;
2427
2428 ukp = user_key_payload_locked(key);
2429 if (!ukp)
2430 return -EKEYREVOKED;
2431
2432 if (cc->key_size != ukp->datalen)
2433 return -EINVAL;
2434
2435 memcpy(cc->key, ukp->data, cc->key_size);
2436
2437 return 0;
2438}
2439
2440static int set_key_encrypted(struct crypt_config *cc, struct key *key)
2441{
2442 const struct encrypted_key_payload *ekp;
2443
2444 ekp = key->payload.data[0];
2445 if (!ekp)
2446 return -EKEYREVOKED;
2447
2448 if (cc->key_size != ekp->decrypted_datalen)
2449 return -EINVAL;
2450
2451 memcpy(cc->key, ekp->decrypted_data, cc->key_size);
2452
2453 return 0;
2454}
2455
2456static int set_key_trusted(struct crypt_config *cc, struct key *key)
2457{
2458 const struct trusted_key_payload *tkp;
2459
2460 tkp = key->payload.data[0];
2461 if (!tkp)
2462 return -EKEYREVOKED;
2463
2464 if (cc->key_size != tkp->key_len)
2465 return -EINVAL;
2466
2467 memcpy(cc->key, tkp->key, cc->key_size);
2468
2469 return 0;
2470}
2471
2472static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2473{
2474 char *new_key_string, *key_desc;
2475 int ret;
2476 struct key_type *type;
2477 struct key *key;
2478 int (*set_key)(struct crypt_config *cc, struct key *key);
2479
2480 /*
2481 * Reject key_string with whitespace. dm core currently lacks code for
2482 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2483 */
2484 if (contains_whitespace(key_string)) {
2485 DMERR("whitespace chars not allowed in key string");
2486 return -EINVAL;
2487 }
2488
2489 /* look for next ':' separating key_type from key_description */
2490 key_desc = strpbrk(key_string, ":");
2491 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2492 return -EINVAL;
2493
2494 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
2495 type = &key_type_logon;
2496 set_key = set_key_user;
2497 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
2498 type = &key_type_user;
2499 set_key = set_key_user;
2500 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) &&
2501 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
2502 type = &key_type_encrypted;
2503 set_key = set_key_encrypted;
2504 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) &&
2505 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) {
2506 type = &key_type_trusted;
2507 set_key = set_key_trusted;
2508 } else {
2509 return -EINVAL;
2510 }
2511
2512 new_key_string = kstrdup(key_string, GFP_KERNEL);
2513 if (!new_key_string)
2514 return -ENOMEM;
2515
2516 key = request_key(type, key_desc + 1, NULL);
2517 if (IS_ERR(key)) {
2518 kfree_sensitive(new_key_string);
2519 return PTR_ERR(key);
2520 }
2521
2522 down_read(&key->sem);
2523
2524 ret = set_key(cc, key);
2525 if (ret < 0) {
2526 up_read(&key->sem);
2527 key_put(key);
2528 kfree_sensitive(new_key_string);
2529 return ret;
2530 }
2531
2532 up_read(&key->sem);
2533 key_put(key);
2534
2535 /* clear the flag since following operations may invalidate previously valid key */
2536 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2537
2538 ret = crypt_setkey(cc);
2539
2540 if (!ret) {
2541 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2542 kfree_sensitive(cc->key_string);
2543 cc->key_string = new_key_string;
2544 } else
2545 kfree_sensitive(new_key_string);
2546
2547 return ret;
2548}
2549
2550static int get_key_size(char **key_string)
2551{
2552 char *colon, dummy;
2553 int ret;
2554
2555 if (*key_string[0] != ':')
2556 return strlen(*key_string) >> 1;
2557
2558 /* look for next ':' in key string */
2559 colon = strpbrk(*key_string + 1, ":");
2560 if (!colon)
2561 return -EINVAL;
2562
2563 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2564 return -EINVAL;
2565
2566 *key_string = colon;
2567
2568 /* remaining key string should be :<logon|user>:<key_desc> */
2569
2570 return ret;
2571}
2572
2573#else
2574
2575static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2576{
2577 return -EINVAL;
2578}
2579
2580static int get_key_size(char **key_string)
2581{
2582 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1);
2583}
2584
2585#endif /* CONFIG_KEYS */
2586
2587static int crypt_set_key(struct crypt_config *cc, char *key)
2588{
2589 int r = -EINVAL;
2590 int key_string_len = strlen(key);
2591
2592 /* Hyphen (which gives a key_size of zero) means there is no key. */
2593 if (!cc->key_size && strcmp(key, "-"))
2594 goto out;
2595
2596 /* ':' means the key is in kernel keyring, short-circuit normal key processing */
2597 if (key[0] == ':') {
2598 r = crypt_set_keyring_key(cc, key + 1);
2599 goto out;
2600 }
2601
2602 /* clear the flag since following operations may invalidate previously valid key */
2603 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2604
2605 /* wipe references to any kernel keyring key */
2606 kfree_sensitive(cc->key_string);
2607 cc->key_string = NULL;
2608
2609 /* Decode key from its hex representation. */
2610 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2611 goto out;
2612
2613 r = crypt_setkey(cc);
2614 if (!r)
2615 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2616
2617out:
2618 /* Hex key string not needed after here, so wipe it. */
2619 memset(key, '0', key_string_len);
2620
2621 return r;
2622}
2623
2624static int crypt_wipe_key(struct crypt_config *cc)
2625{
2626 int r;
2627
2628 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2629 get_random_bytes(&cc->key, cc->key_size);
2630
2631 /* Wipe IV private keys */
2632 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2633 r = cc->iv_gen_ops->wipe(cc);
2634 if (r)
2635 return r;
2636 }
2637
2638 kfree_sensitive(cc->key_string);
2639 cc->key_string = NULL;
2640 r = crypt_setkey(cc);
2641 memset(&cc->key, 0, cc->key_size * sizeof(u8));
2642
2643 return r;
2644}
2645
2646static void crypt_calculate_pages_per_client(void)
2647{
2648 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
2649
2650 if (!dm_crypt_clients_n)
2651 return;
2652
2653 pages /= dm_crypt_clients_n;
2654 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
2655 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
2656 dm_crypt_pages_per_client = pages;
2657}
2658
2659static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
2660{
2661 struct crypt_config *cc = pool_data;
2662 struct page *page;
2663
2664 /*
2665 * Note, percpu_counter_read_positive() may over (and under) estimate
2666 * the current usage by at most (batch - 1) * num_online_cpus() pages,
2667 * but avoids potential spinlock contention of an exact result.
2668 */
2669 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) &&
2670 likely(gfp_mask & __GFP_NORETRY))
2671 return NULL;
2672
2673 page = alloc_page(gfp_mask);
2674 if (likely(page != NULL))
2675 percpu_counter_add(&cc->n_allocated_pages, 1);
2676
2677 return page;
2678}
2679
2680static void crypt_page_free(void *page, void *pool_data)
2681{
2682 struct crypt_config *cc = pool_data;
2683
2684 __free_page(page);
2685 percpu_counter_sub(&cc->n_allocated_pages, 1);
2686}
2687
2688static void crypt_dtr(struct dm_target *ti)
2689{
2690 struct crypt_config *cc = ti->private;
2691
2692 ti->private = NULL;
2693
2694 if (!cc)
2695 return;
2696
2697 if (cc->write_thread)
2698 kthread_stop(cc->write_thread);
2699
2700 if (cc->io_queue)
2701 destroy_workqueue(cc->io_queue);
2702 if (cc->crypt_queue)
2703 destroy_workqueue(cc->crypt_queue);
2704
2705 crypt_free_tfms(cc);
2706
2707 bioset_exit(&cc->bs);
2708
2709 mempool_exit(&cc->page_pool);
2710 mempool_exit(&cc->req_pool);
2711 mempool_exit(&cc->tag_pool);
2712
2713 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
2714 percpu_counter_destroy(&cc->n_allocated_pages);
2715
2716 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2717 cc->iv_gen_ops->dtr(cc);
2718
2719 if (cc->dev)
2720 dm_put_device(ti, cc->dev);
2721
2722 kfree_sensitive(cc->cipher_string);
2723 kfree_sensitive(cc->key_string);
2724 kfree_sensitive(cc->cipher_auth);
2725 kfree_sensitive(cc->authenc_key);
2726
2727 mutex_destroy(&cc->bio_alloc_lock);
2728
2729 /* Must zero key material before freeing */
2730 kfree_sensitive(cc);
2731
2732 spin_lock(&dm_crypt_clients_lock);
2733 WARN_ON(!dm_crypt_clients_n);
2734 dm_crypt_clients_n--;
2735 crypt_calculate_pages_per_client();
2736 spin_unlock(&dm_crypt_clients_lock);
2737
2738 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1);
2739}
2740
2741static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2742{
2743 struct crypt_config *cc = ti->private;
2744
2745 if (crypt_integrity_aead(cc))
2746 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2747 else
2748 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2749
2750 if (cc->iv_size)
2751 /* at least a 64 bit sector number should fit in our buffer */
2752 cc->iv_size = max(cc->iv_size,
2753 (unsigned int)(sizeof(u64) / sizeof(u8)));
2754 else if (ivmode) {
2755 DMWARN("Selected cipher does not support IVs");
2756 ivmode = NULL;
2757 }
2758
2759 /* Choose ivmode, see comments at iv code. */
2760 if (ivmode == NULL)
2761 cc->iv_gen_ops = NULL;
2762 else if (strcmp(ivmode, "plain") == 0)
2763 cc->iv_gen_ops = &crypt_iv_plain_ops;
2764 else if (strcmp(ivmode, "plain64") == 0)
2765 cc->iv_gen_ops = &crypt_iv_plain64_ops;
2766 else if (strcmp(ivmode, "plain64be") == 0)
2767 cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2768 else if (strcmp(ivmode, "essiv") == 0)
2769 cc->iv_gen_ops = &crypt_iv_essiv_ops;
2770 else if (strcmp(ivmode, "benbi") == 0)
2771 cc->iv_gen_ops = &crypt_iv_benbi_ops;
2772 else if (strcmp(ivmode, "null") == 0)
2773 cc->iv_gen_ops = &crypt_iv_null_ops;
2774 else if (strcmp(ivmode, "eboiv") == 0)
2775 cc->iv_gen_ops = &crypt_iv_eboiv_ops;
2776 else if (strcmp(ivmode, "elephant") == 0) {
2777 cc->iv_gen_ops = &crypt_iv_elephant_ops;
2778 cc->key_parts = 2;
2779 cc->key_extra_size = cc->key_size / 2;
2780 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
2781 return -EINVAL;
2782 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
2783 } else if (strcmp(ivmode, "lmk") == 0) {
2784 cc->iv_gen_ops = &crypt_iv_lmk_ops;
2785 /*
2786 * Version 2 and 3 is recognised according
2787 * to length of provided multi-key string.
2788 * If present (version 3), last key is used as IV seed.
2789 * All keys (including IV seed) are always the same size.
2790 */
2791 if (cc->key_size % cc->key_parts) {
2792 cc->key_parts++;
2793 cc->key_extra_size = cc->key_size / cc->key_parts;
2794 }
2795 } else if (strcmp(ivmode, "tcw") == 0) {
2796 cc->iv_gen_ops = &crypt_iv_tcw_ops;
2797 cc->key_parts += 2; /* IV + whitening */
2798 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2799 } else if (strcmp(ivmode, "random") == 0) {
2800 cc->iv_gen_ops = &crypt_iv_random_ops;
2801 /* Need storage space in integrity fields. */
2802 cc->integrity_iv_size = cc->iv_size;
2803 } else {
2804 ti->error = "Invalid IV mode";
2805 return -EINVAL;
2806 }
2807
2808 return 0;
2809}
2810
2811/*
2812 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2813 * The HMAC is needed to calculate tag size (HMAC digest size).
2814 * This should be probably done by crypto-api calls (once available...)
2815 */
2816static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2817{
2818 char *start, *end, *mac_alg = NULL;
2819 struct crypto_ahash *mac;
2820
2821 if (!strstarts(cipher_api, "authenc("))
2822 return 0;
2823
2824 start = strchr(cipher_api, '(');
2825 end = strchr(cipher_api, ',');
2826 if (!start || !end || ++start > end)
2827 return -EINVAL;
2828
2829 mac_alg = kzalloc(end - start + 1, GFP_KERNEL);
2830 if (!mac_alg)
2831 return -ENOMEM;
2832 strncpy(mac_alg, start, end - start);
2833
2834 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY);
2835 kfree(mac_alg);
2836
2837 if (IS_ERR(mac))
2838 return PTR_ERR(mac);
2839
2840 cc->key_mac_size = crypto_ahash_digestsize(mac);
2841 crypto_free_ahash(mac);
2842
2843 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2844 if (!cc->authenc_key)
2845 return -ENOMEM;
2846
2847 return 0;
2848}
2849
2850static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2851 char **ivmode, char **ivopts)
2852{
2853 struct crypt_config *cc = ti->private;
2854 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
2855 int ret = -EINVAL;
2856
2857 cc->tfms_count = 1;
2858
2859 /*
2860 * New format (capi: prefix)
2861 * capi:cipher_api_spec-iv:ivopts
2862 */
2863 tmp = &cipher_in[strlen("capi:")];
2864
2865 /* Separate IV options if present, it can contain another '-' in hash name */
2866 *ivopts = strrchr(tmp, ':');
2867 if (*ivopts) {
2868 **ivopts = '\0';
2869 (*ivopts)++;
2870 }
2871 /* Parse IV mode */
2872 *ivmode = strrchr(tmp, '-');
2873 if (*ivmode) {
2874 **ivmode = '\0';
2875 (*ivmode)++;
2876 }
2877 /* The rest is crypto API spec */
2878 cipher_api = tmp;
2879
2880 /* Alloc AEAD, can be used only in new format. */
2881 if (crypt_integrity_aead(cc)) {
2882 ret = crypt_ctr_auth_cipher(cc, cipher_api);
2883 if (ret < 0) {
2884 ti->error = "Invalid AEAD cipher spec";
2885 return -ENOMEM;
2886 }
2887 }
2888
2889 if (*ivmode && !strcmp(*ivmode, "lmk"))
2890 cc->tfms_count = 64;
2891
2892 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2893 if (!*ivopts) {
2894 ti->error = "Digest algorithm missing for ESSIV mode";
2895 return -EINVAL;
2896 }
2897 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
2898 cipher_api, *ivopts);
2899 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2900 ti->error = "Cannot allocate cipher string";
2901 return -ENOMEM;
2902 }
2903 cipher_api = buf;
2904 }
2905
2906 cc->key_parts = cc->tfms_count;
2907
2908 /* Allocate cipher */
2909 ret = crypt_alloc_tfms(cc, cipher_api);
2910 if (ret < 0) {
2911 ti->error = "Error allocating crypto tfm";
2912 return ret;
2913 }
2914
2915 if (crypt_integrity_aead(cc))
2916 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2917 else
2918 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2919
2920 return 0;
2921}
2922
2923static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2924 char **ivmode, char **ivopts)
2925{
2926 struct crypt_config *cc = ti->private;
2927 char *tmp, *cipher, *chainmode, *keycount;
2928 char *cipher_api = NULL;
2929 int ret = -EINVAL;
2930 char dummy;
2931
2932 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2933 ti->error = "Bad cipher specification";
2934 return -EINVAL;
2935 }
2936
2937 /*
2938 * Legacy dm-crypt cipher specification
2939 * cipher[:keycount]-mode-iv:ivopts
2940 */
2941 tmp = cipher_in;
2942 keycount = strsep(&tmp, "-");
2943 cipher = strsep(&keycount, ":");
2944
2945 if (!keycount)
2946 cc->tfms_count = 1;
2947 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
2948 !is_power_of_2(cc->tfms_count)) {
2949 ti->error = "Bad cipher key count specification";
2950 return -EINVAL;
2951 }
2952 cc->key_parts = cc->tfms_count;
2953
2954 chainmode = strsep(&tmp, "-");
2955 *ivmode = strsep(&tmp, ":");
2956 *ivopts = tmp;
2957
2958 /*
2959 * For compatibility with the original dm-crypt mapping format, if
2960 * only the cipher name is supplied, use cbc-plain.
2961 */
2962 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
2963 chainmode = "cbc";
2964 *ivmode = "plain";
2965 }
2966
2967 if (strcmp(chainmode, "ecb") && !*ivmode) {
2968 ti->error = "IV mechanism required";
2969 return -EINVAL;
2970 }
2971
2972 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
2973 if (!cipher_api)
2974 goto bad_mem;
2975
2976 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2977 if (!*ivopts) {
2978 ti->error = "Digest algorithm missing for ESSIV mode";
2979 kfree(cipher_api);
2980 return -EINVAL;
2981 }
2982 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2983 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
2984 } else {
2985 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2986 "%s(%s)", chainmode, cipher);
2987 }
2988 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2989 kfree(cipher_api);
2990 goto bad_mem;
2991 }
2992
2993 /* Allocate cipher */
2994 ret = crypt_alloc_tfms(cc, cipher_api);
2995 if (ret < 0) {
2996 ti->error = "Error allocating crypto tfm";
2997 kfree(cipher_api);
2998 return ret;
2999 }
3000 kfree(cipher_api);
3001
3002 return 0;
3003bad_mem:
3004 ti->error = "Cannot allocate cipher strings";
3005 return -ENOMEM;
3006}
3007
3008static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
3009{
3010 struct crypt_config *cc = ti->private;
3011 char *ivmode = NULL, *ivopts = NULL;
3012 int ret;
3013
3014 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
3015 if (!cc->cipher_string) {
3016 ti->error = "Cannot allocate cipher strings";
3017 return -ENOMEM;
3018 }
3019
3020 if (strstarts(cipher_in, "capi:"))
3021 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
3022 else
3023 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
3024 if (ret)
3025 return ret;
3026
3027 /* Initialize IV */
3028 ret = crypt_ctr_ivmode(ti, ivmode);
3029 if (ret < 0)
3030 return ret;
3031
3032 /* Initialize and set key */
3033 ret = crypt_set_key(cc, key);
3034 if (ret < 0) {
3035 ti->error = "Error decoding and setting key";
3036 return ret;
3037 }
3038
3039 /* Allocate IV */
3040 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
3041 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
3042 if (ret < 0) {
3043 ti->error = "Error creating IV";
3044 return ret;
3045 }
3046 }
3047
3048 /* Initialize IV (set keys for ESSIV etc) */
3049 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
3050 ret = cc->iv_gen_ops->init(cc);
3051 if (ret < 0) {
3052 ti->error = "Error initialising IV";
3053 return ret;
3054 }
3055 }
3056
3057 /* wipe the kernel key payload copy */
3058 if (cc->key_string)
3059 memset(cc->key, 0, cc->key_size * sizeof(u8));
3060
3061 return ret;
3062}
3063
3064static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
3065{
3066 struct crypt_config *cc = ti->private;
3067 struct dm_arg_set as;
3068 static const struct dm_arg _args[] = {
3069 {0, 8, "Invalid number of feature args"},
3070 };
3071 unsigned int opt_params, val;
3072 const char *opt_string, *sval;
3073 char dummy;
3074 int ret;
3075
3076 /* Optional parameters */
3077 as.argc = argc;
3078 as.argv = argv;
3079
3080 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
3081 if (ret)
3082 return ret;
3083
3084 while (opt_params--) {
3085 opt_string = dm_shift_arg(&as);
3086 if (!opt_string) {
3087 ti->error = "Not enough feature arguments";
3088 return -EINVAL;
3089 }
3090
3091 if (!strcasecmp(opt_string, "allow_discards"))
3092 ti->num_discard_bios = 1;
3093
3094 else if (!strcasecmp(opt_string, "same_cpu_crypt"))
3095 set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3096
3097 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
3098 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3099 else if (!strcasecmp(opt_string, "no_read_workqueue"))
3100 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3101 else if (!strcasecmp(opt_string, "no_write_workqueue"))
3102 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3103 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
3104 if (val == 0 || val > MAX_TAG_SIZE) {
3105 ti->error = "Invalid integrity arguments";
3106 return -EINVAL;
3107 }
3108 cc->on_disk_tag_size = val;
3109 sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
3110 if (!strcasecmp(sval, "aead")) {
3111 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
3112 } else if (strcasecmp(sval, "none")) {
3113 ti->error = "Unknown integrity profile";
3114 return -EINVAL;
3115 }
3116
3117 cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
3118 if (!cc->cipher_auth)
3119 return -ENOMEM;
3120 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
3121 if (cc->sector_size < (1 << SECTOR_SHIFT) ||
3122 cc->sector_size > 4096 ||
3123 (cc->sector_size & (cc->sector_size - 1))) {
3124 ti->error = "Invalid feature value for sector_size";
3125 return -EINVAL;
3126 }
3127 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
3128 ti->error = "Device size is not multiple of sector_size feature";
3129 return -EINVAL;
3130 }
3131 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
3132 } else if (!strcasecmp(opt_string, "iv_large_sectors"))
3133 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3134 else {
3135 ti->error = "Invalid feature arguments";
3136 return -EINVAL;
3137 }
3138 }
3139
3140 return 0;
3141}
3142
3143#ifdef CONFIG_BLK_DEV_ZONED
3144static int crypt_report_zones(struct dm_target *ti,
3145 struct dm_report_zones_args *args, unsigned int nr_zones)
3146{
3147 struct crypt_config *cc = ti->private;
3148
3149 return dm_report_zones(cc->dev->bdev, cc->start,
3150 cc->start + dm_target_offset(ti, args->next_sector),
3151 args, nr_zones);
3152}
3153#else
3154#define crypt_report_zones NULL
3155#endif
3156
3157/*
3158 * Construct an encryption mapping:
3159 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
3160 */
3161static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3162{
3163 struct crypt_config *cc;
3164 const char *devname = dm_table_device_name(ti->table);
3165 int key_size;
3166 unsigned int align_mask;
3167 unsigned long long tmpll;
3168 int ret;
3169 size_t iv_size_padding, additional_req_size;
3170 char dummy;
3171
3172 if (argc < 5) {
3173 ti->error = "Not enough arguments";
3174 return -EINVAL;
3175 }
3176
3177 key_size = get_key_size(&argv[1]);
3178 if (key_size < 0) {
3179 ti->error = "Cannot parse key size";
3180 return -EINVAL;
3181 }
3182
3183 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
3184 if (!cc) {
3185 ti->error = "Cannot allocate encryption context";
3186 return -ENOMEM;
3187 }
3188 cc->key_size = key_size;
3189 cc->sector_size = (1 << SECTOR_SHIFT);
3190 cc->sector_shift = 0;
3191
3192 ti->private = cc;
3193
3194 spin_lock(&dm_crypt_clients_lock);
3195 dm_crypt_clients_n++;
3196 crypt_calculate_pages_per_client();
3197 spin_unlock(&dm_crypt_clients_lock);
3198
3199 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
3200 if (ret < 0)
3201 goto bad;
3202
3203 /* Optional parameters need to be read before cipher constructor */
3204 if (argc > 5) {
3205 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
3206 if (ret)
3207 goto bad;
3208 }
3209
3210 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
3211 if (ret < 0)
3212 goto bad;
3213
3214 if (crypt_integrity_aead(cc)) {
3215 cc->dmreq_start = sizeof(struct aead_request);
3216 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
3217 align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
3218 } else {
3219 cc->dmreq_start = sizeof(struct skcipher_request);
3220 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
3221 align_mask = crypto_skcipher_alignmask(any_tfm(cc));
3222 }
3223 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
3224
3225 if (align_mask < CRYPTO_MINALIGN) {
3226 /* Allocate the padding exactly */
3227 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
3228 & align_mask;
3229 } else {
3230 /*
3231 * If the cipher requires greater alignment than kmalloc
3232 * alignment, we don't know the exact position of the
3233 * initialization vector. We must assume worst case.
3234 */
3235 iv_size_padding = align_mask;
3236 }
3237
3238 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */
3239 additional_req_size = sizeof(struct dm_crypt_request) +
3240 iv_size_padding + cc->iv_size +
3241 cc->iv_size +
3242 sizeof(uint64_t) +
3243 sizeof(unsigned int);
3244
3245 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
3246 if (ret) {
3247 ti->error = "Cannot allocate crypt request mempool";
3248 goto bad;
3249 }
3250
3251 cc->per_bio_data_size = ti->per_io_data_size =
3252 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
3253 ARCH_KMALLOC_MINALIGN);
3254
3255 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc);
3256 if (ret) {
3257 ti->error = "Cannot allocate page mempool";
3258 goto bad;
3259 }
3260
3261 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
3262 if (ret) {
3263 ti->error = "Cannot allocate crypt bioset";
3264 goto bad;
3265 }
3266
3267 mutex_init(&cc->bio_alloc_lock);
3268
3269 ret = -EINVAL;
3270 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
3271 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
3272 ti->error = "Invalid iv_offset sector";
3273 goto bad;
3274 }
3275 cc->iv_offset = tmpll;
3276
3277 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
3278 if (ret) {
3279 ti->error = "Device lookup failed";
3280 goto bad;
3281 }
3282
3283 ret = -EINVAL;
3284 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
3285 ti->error = "Invalid device sector";
3286 goto bad;
3287 }
3288 cc->start = tmpll;
3289
3290 if (bdev_is_zoned(cc->dev->bdev)) {
3291 /*
3292 * For zoned block devices, we need to preserve the issuer write
3293 * ordering. To do so, disable write workqueues and force inline
3294 * encryption completion.
3295 */
3296 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3297 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
3298
3299 /*
3300 * All zone append writes to a zone of a zoned block device will
3301 * have the same BIO sector, the start of the zone. When the
3302 * cypher IV mode uses sector values, all data targeting a
3303 * zone will be encrypted using the first sector numbers of the
3304 * zone. This will not result in write errors but will
3305 * cause most reads to fail as reads will use the sector values
3306 * for the actual data locations, resulting in IV mismatch.
3307 * To avoid this problem, ask DM core to emulate zone append
3308 * operations with regular writes.
3309 */
3310 DMDEBUG("Zone append operations will be emulated");
3311 ti->emulate_zone_append = true;
3312 }
3313
3314 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
3315 ret = crypt_integrity_ctr(cc, ti);
3316 if (ret)
3317 goto bad;
3318
3319 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
3320 if (!cc->tag_pool_max_sectors)
3321 cc->tag_pool_max_sectors = 1;
3322
3323 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
3324 cc->tag_pool_max_sectors * cc->on_disk_tag_size);
3325 if (ret) {
3326 ti->error = "Cannot allocate integrity tags mempool";
3327 goto bad;
3328 }
3329
3330 cc->tag_pool_max_sectors <<= cc->sector_shift;
3331 }
3332
3333 ret = -ENOMEM;
3334 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname);
3335 if (!cc->io_queue) {
3336 ti->error = "Couldn't create kcryptd io queue";
3337 goto bad;
3338 }
3339
3340 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3341 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
3342 1, devname);
3343 else
3344 cc->crypt_queue = alloc_workqueue("kcryptd/%s",
3345 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
3346 num_online_cpus(), devname);
3347 if (!cc->crypt_queue) {
3348 ti->error = "Couldn't create kcryptd queue";
3349 goto bad;
3350 }
3351
3352 spin_lock_init(&cc->write_thread_lock);
3353 cc->write_tree = RB_ROOT;
3354
3355 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
3356 if (IS_ERR(cc->write_thread)) {
3357 ret = PTR_ERR(cc->write_thread);
3358 cc->write_thread = NULL;
3359 ti->error = "Couldn't spawn write thread";
3360 goto bad;
3361 }
3362
3363 ti->num_flush_bios = 1;
3364 ti->limit_swap_bios = true;
3365 ti->accounts_remapped_io = true;
3366
3367 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1);
3368 return 0;
3369
3370bad:
3371 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0);
3372 crypt_dtr(ti);
3373 return ret;
3374}
3375
3376static int crypt_map(struct dm_target *ti, struct bio *bio)
3377{
3378 struct dm_crypt_io *io;
3379 struct crypt_config *cc = ti->private;
3380
3381 /*
3382 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
3383 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
3384 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
3385 */
3386 if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
3387 bio_op(bio) == REQ_OP_DISCARD)) {
3388 bio_set_dev(bio, cc->dev->bdev);
3389 if (bio_sectors(bio))
3390 bio->bi_iter.bi_sector = cc->start +
3391 dm_target_offset(ti, bio->bi_iter.bi_sector);
3392 return DM_MAPIO_REMAPPED;
3393 }
3394
3395 /*
3396 * Check if bio is too large, split as needed.
3397 */
3398 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) &&
3399 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
3400 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT));
3401
3402 /*
3403 * Ensure that bio is a multiple of internal sector encryption size
3404 * and is aligned to this size as defined in IO hints.
3405 */
3406 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
3407 return DM_MAPIO_KILL;
3408
3409 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
3410 return DM_MAPIO_KILL;
3411
3412 io = dm_per_bio_data(bio, cc->per_bio_data_size);
3413 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
3414
3415 if (cc->on_disk_tag_size) {
3416 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
3417
3418 if (unlikely(tag_len > KMALLOC_MAX_SIZE) ||
3419 unlikely(!(io->integrity_metadata = kmalloc(tag_len,
3420 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) {
3421 if (bio_sectors(bio) > cc->tag_pool_max_sectors)
3422 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
3423 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
3424 io->integrity_metadata_from_pool = true;
3425 }
3426 }
3427
3428 if (crypt_integrity_aead(cc))
3429 io->ctx.r.req_aead = (struct aead_request *)(io + 1);
3430 else
3431 io->ctx.r.req = (struct skcipher_request *)(io + 1);
3432
3433 if (bio_data_dir(io->base_bio) == READ) {
3434 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP))
3435 kcryptd_queue_read(io);
3436 } else
3437 kcryptd_queue_crypt(io);
3438
3439 return DM_MAPIO_SUBMITTED;
3440}
3441
3442static char hex2asc(unsigned char c)
3443{
3444 return c + '0' + ((unsigned)(9 - c) >> 4 & 0x27);
3445}
3446
3447static void crypt_status(struct dm_target *ti, status_type_t type,
3448 unsigned status_flags, char *result, unsigned maxlen)
3449{
3450 struct crypt_config *cc = ti->private;
3451 unsigned i, sz = 0;
3452 int num_feature_args = 0;
3453
3454 switch (type) {
3455 case STATUSTYPE_INFO:
3456 result[0] = '\0';
3457 break;
3458
3459 case STATUSTYPE_TABLE:
3460 DMEMIT("%s ", cc->cipher_string);
3461
3462 if (cc->key_size > 0) {
3463 if (cc->key_string)
3464 DMEMIT(":%u:%s", cc->key_size, cc->key_string);
3465 else {
3466 for (i = 0; i < cc->key_size; i++) {
3467 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4),
3468 hex2asc(cc->key[i] & 0xf));
3469 }
3470 }
3471 } else
3472 DMEMIT("-");
3473
3474 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
3475 cc->dev->name, (unsigned long long)cc->start);
3476
3477 num_feature_args += !!ti->num_discard_bios;
3478 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3479 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3480 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3481 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3482 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
3483 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3484 if (cc->on_disk_tag_size)
3485 num_feature_args++;
3486 if (num_feature_args) {
3487 DMEMIT(" %d", num_feature_args);
3488 if (ti->num_discard_bios)
3489 DMEMIT(" allow_discards");
3490 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3491 DMEMIT(" same_cpu_crypt");
3492 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
3493 DMEMIT(" submit_from_crypt_cpus");
3494 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
3495 DMEMIT(" no_read_workqueue");
3496 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
3497 DMEMIT(" no_write_workqueue");
3498 if (cc->on_disk_tag_size)
3499 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
3500 if (cc->sector_size != (1 << SECTOR_SHIFT))
3501 DMEMIT(" sector_size:%d", cc->sector_size);
3502 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
3503 DMEMIT(" iv_large_sectors");
3504 }
3505 break;
3506
3507 case STATUSTYPE_IMA:
3508 DMEMIT_TARGET_NAME_VERSION(ti->type);
3509 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n');
3510 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n');
3511 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ?
3512 'y' : 'n');
3513 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ?
3514 'y' : 'n');
3515 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ?
3516 'y' : 'n');
3517 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ?
3518 'y' : 'n');
3519
3520 if (cc->on_disk_tag_size)
3521 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s",
3522 cc->on_disk_tag_size, cc->cipher_auth);
3523 if (cc->sector_size != (1 << SECTOR_SHIFT))
3524 DMEMIT(",sector_size=%d", cc->sector_size);
3525 if (cc->cipher_string)
3526 DMEMIT(",cipher_string=%s", cc->cipher_string);
3527
3528 DMEMIT(",key_size=%u", cc->key_size);
3529 DMEMIT(",key_parts=%u", cc->key_parts);
3530 DMEMIT(",key_extra_size=%u", cc->key_extra_size);
3531 DMEMIT(",key_mac_size=%u", cc->key_mac_size);
3532 DMEMIT(";");
3533 break;
3534 }
3535}
3536
3537static void crypt_postsuspend(struct dm_target *ti)
3538{
3539 struct crypt_config *cc = ti->private;
3540
3541 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3542}
3543
3544static int crypt_preresume(struct dm_target *ti)
3545{
3546 struct crypt_config *cc = ti->private;
3547
3548 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
3549 DMERR("aborting resume - crypt key is not set.");
3550 return -EAGAIN;
3551 }
3552
3553 return 0;
3554}
3555
3556static void crypt_resume(struct dm_target *ti)
3557{
3558 struct crypt_config *cc = ti->private;
3559
3560 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3561}
3562
3563/* Message interface
3564 * key set <key>
3565 * key wipe
3566 */
3567static int crypt_message(struct dm_target *ti, unsigned argc, char **argv,
3568 char *result, unsigned maxlen)
3569{
3570 struct crypt_config *cc = ti->private;
3571 int key_size, ret = -EINVAL;
3572
3573 if (argc < 2)
3574 goto error;
3575
3576 if (!strcasecmp(argv[0], "key")) {
3577 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
3578 DMWARN("not suspended during key manipulation.");
3579 return -EINVAL;
3580 }
3581 if (argc == 3 && !strcasecmp(argv[1], "set")) {
3582 /* The key size may not be changed. */
3583 key_size = get_key_size(&argv[2]);
3584 if (key_size < 0 || cc->key_size != key_size) {
3585 memset(argv[2], '0', strlen(argv[2]));
3586 return -EINVAL;
3587 }
3588
3589 ret = crypt_set_key(cc, argv[2]);
3590 if (ret)
3591 return ret;
3592 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
3593 ret = cc->iv_gen_ops->init(cc);
3594 /* wipe the kernel key payload copy */
3595 if (cc->key_string)
3596 memset(cc->key, 0, cc->key_size * sizeof(u8));
3597 return ret;
3598 }
3599 if (argc == 2 && !strcasecmp(argv[1], "wipe"))
3600 return crypt_wipe_key(cc);
3601 }
3602
3603error:
3604 DMWARN("unrecognised message received.");
3605 return -EINVAL;
3606}
3607
3608static int crypt_iterate_devices(struct dm_target *ti,
3609 iterate_devices_callout_fn fn, void *data)
3610{
3611 struct crypt_config *cc = ti->private;
3612
3613 return fn(ti, cc->dev, cc->start, ti->len, data);
3614}
3615
3616static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
3617{
3618 struct crypt_config *cc = ti->private;
3619
3620 /*
3621 * Unfortunate constraint that is required to avoid the potential
3622 * for exceeding underlying device's max_segments limits -- due to
3623 * crypt_alloc_buffer() possibly allocating pages for the encryption
3624 * bio that are not as physically contiguous as the original bio.
3625 */
3626 limits->max_segment_size = PAGE_SIZE;
3627
3628 limits->logical_block_size =
3629 max_t(unsigned, limits->logical_block_size, cc->sector_size);
3630 limits->physical_block_size =
3631 max_t(unsigned, limits->physical_block_size, cc->sector_size);
3632 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size);
3633 limits->dma_alignment = limits->logical_block_size - 1;
3634}
3635
3636static struct target_type crypt_target = {
3637 .name = "crypt",
3638 .version = {1, 24, 0},
3639 .module = THIS_MODULE,
3640 .ctr = crypt_ctr,
3641 .dtr = crypt_dtr,
3642 .features = DM_TARGET_ZONED_HM,
3643 .report_zones = crypt_report_zones,
3644 .map = crypt_map,
3645 .status = crypt_status,
3646 .postsuspend = crypt_postsuspend,
3647 .preresume = crypt_preresume,
3648 .resume = crypt_resume,
3649 .message = crypt_message,
3650 .iterate_devices = crypt_iterate_devices,
3651 .io_hints = crypt_io_hints,
3652};
3653
3654static int __init dm_crypt_init(void)
3655{
3656 int r;
3657
3658 r = dm_register_target(&crypt_target);
3659 if (r < 0)
3660 DMERR("register failed %d", r);
3661
3662 return r;
3663}
3664
3665static void __exit dm_crypt_exit(void)
3666{
3667 dm_unregister_target(&crypt_target);
3668}
3669
3670module_init(dm_crypt_init);
3671module_exit(dm_crypt_exit);
3672
3673MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3674MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3675MODULE_LICENSE("GPL");