Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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/hex.h>
15#include <linux/init.h>
16#include <linux/kernel.h>
17#include <linux/key.h>
18#include <linux/bio.h>
19#include <linux/blkdev.h>
20#include <linux/blk-integrity.h>
21#include <linux/crc32.h>
22#include <linux/mempool.h>
23#include <linux/slab.h>
24#include <linux/crypto.h>
25#include <linux/fips.h>
26#include <linux/workqueue.h>
27#include <linux/kthread.h>
28#include <linux/backing-dev.h>
29#include <linux/atomic.h>
30#include <linux/scatterlist.h>
31#include <linux/rbtree.h>
32#include <linux/ctype.h>
33#include <asm/page.h>
34#include <linux/unaligned.h>
35#include <crypto/aes.h>
36#include <crypto/hash.h>
37#include <crypto/md5.h>
38#include <crypto/skcipher.h>
39#include <crypto/aead.h>
40#include <crypto/authenc.h>
41#include <crypto/utils.h>
42#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
43#include <linux/key-type.h>
44#include <keys/user-type.h>
45#include <keys/encrypted-type.h>
46#include <keys/trusted-type.h>
47
48#include <linux/device-mapper.h>
49
50#include "dm-audit.h"
51
52#define DM_MSG_PREFIX "crypt"
53
54static DEFINE_IDA(workqueue_ida);
55
56/*
57 * context holding the current state of a multi-part conversion
58 */
59struct convert_context {
60 struct completion restart;
61 struct bio *bio_in;
62 struct bvec_iter iter_in;
63 struct bio *bio_out;
64 struct bvec_iter iter_out;
65 atomic_t cc_pending;
66 unsigned int tag_offset;
67 u64 cc_sector;
68 union {
69 struct skcipher_request *req;
70 struct aead_request *req_aead;
71 } r;
72 bool aead_recheck;
73 bool aead_failed;
74
75};
76
77/*
78 * per bio private data
79 */
80struct dm_crypt_io {
81 struct crypt_config *cc;
82 struct bio *base_bio;
83 u8 *integrity_metadata;
84 bool integrity_metadata_from_pool:1;
85
86 struct work_struct work;
87
88 struct convert_context ctx;
89
90 atomic_t io_pending;
91 blk_status_t error;
92 sector_t sector;
93
94 struct bvec_iter saved_bi_iter;
95
96 struct rb_node rb_node;
97} CRYPTO_MINALIGN_ATTR;
98
99struct dm_crypt_request {
100 struct convert_context *ctx;
101 struct scatterlist sg_in[4];
102 struct scatterlist sg_out[4];
103 u64 iv_sector;
104};
105
106struct crypt_config;
107
108struct crypt_iv_operations {
109 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
110 const char *opts);
111 void (*dtr)(struct crypt_config *cc);
112 int (*init)(struct crypt_config *cc);
113 void (*wipe)(struct crypt_config *cc);
114 int (*generator)(struct crypt_config *cc, u8 *iv,
115 struct dm_crypt_request *dmreq);
116 void (*post)(struct crypt_config *cc, u8 *iv,
117 struct dm_crypt_request *dmreq);
118};
119
120struct iv_benbi_private {
121 int shift;
122};
123
124#define LMK_SEED_SIZE 64 /* hash + 0 */
125struct iv_lmk_private {
126 u8 *seed;
127};
128
129#define TCW_WHITENING_SIZE 16
130struct iv_tcw_private {
131 u8 *iv_seed;
132 u8 *whitening;
133};
134
135#define ELEPHANT_MAX_KEY_SIZE 32
136struct iv_elephant_private {
137 struct aes_enckey *key;
138};
139
140/*
141 * Crypt: maps a linear range of a block device
142 * and encrypts / decrypts at the same time.
143 */
144enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
145 DM_CRYPT_SAME_CPU, DM_CRYPT_HIGH_PRIORITY,
146 DM_CRYPT_NO_OFFLOAD, DM_CRYPT_NO_READ_WORKQUEUE,
147 DM_CRYPT_NO_WRITE_WORKQUEUE, DM_CRYPT_WRITE_INLINE };
148
149enum cipher_flags {
150 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */
151 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */
152 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */
153 CRYPT_KEY_MAC_SIZE_SET, /* The integrity_key_size option was used */
154};
155
156/*
157 * The fields in here must be read only after initialization.
158 */
159struct crypt_config {
160 struct dm_dev *dev;
161 sector_t start;
162
163 struct percpu_counter n_allocated_pages;
164
165 struct workqueue_struct *io_queue;
166 struct workqueue_struct *crypt_queue;
167
168 spinlock_t write_thread_lock;
169 struct task_struct *write_thread;
170 struct rb_root write_tree;
171
172 char *cipher_string;
173 char *cipher_auth;
174 char *key_string;
175
176 const struct crypt_iv_operations *iv_gen_ops;
177 union {
178 struct iv_benbi_private benbi;
179 struct iv_lmk_private lmk;
180 struct iv_tcw_private tcw;
181 struct iv_elephant_private elephant;
182 } iv_gen_private;
183 u64 iv_offset;
184 unsigned int iv_size;
185 unsigned short sector_size;
186 unsigned char sector_shift;
187
188 union {
189 struct crypto_skcipher **tfms;
190 struct crypto_aead **tfms_aead;
191 } cipher_tfm;
192 unsigned int tfms_count;
193 int workqueue_id;
194 unsigned long cipher_flags;
195
196 /*
197 * Layout of each crypto request:
198 *
199 * struct skcipher_request
200 * context
201 * padding
202 * struct dm_crypt_request
203 * padding
204 * IV
205 *
206 * The padding is added so that dm_crypt_request and the IV are
207 * correctly aligned.
208 */
209 unsigned int dmreq_start;
210
211 unsigned int per_bio_data_size;
212
213 unsigned long flags;
214 unsigned int key_size;
215 unsigned int key_parts; /* independent parts in key buffer */
216 unsigned int key_extra_size; /* additional keys length */
217 unsigned int key_mac_size; /* MAC key size for authenc(...) */
218
219 unsigned int integrity_tag_size;
220 unsigned int integrity_iv_size;
221 unsigned int used_tag_size;
222 unsigned int tuple_size;
223
224 /*
225 * pool for per bio private data, crypto requests,
226 * encryption requeusts/buffer pages and integrity tags
227 */
228 unsigned int tag_pool_max_sectors;
229 mempool_t tag_pool;
230 mempool_t req_pool;
231 mempool_t page_pool;
232
233 struct bio_set bs;
234 struct mutex bio_alloc_lock;
235
236 u8 *authenc_key; /* space for keys in authenc() format (if used) */
237 u8 key[] __counted_by(key_size);
238};
239
240#define MIN_IOS 64
241#define MAX_TAG_SIZE 480
242#define POOL_ENTRY_SIZE 512
243
244static DEFINE_SPINLOCK(dm_crypt_clients_lock);
245static unsigned int dm_crypt_clients_n;
246static volatile unsigned long dm_crypt_pages_per_client;
247#define DM_CRYPT_MEMORY_PERCENT 2
248#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16)
249#define DM_CRYPT_DEFAULT_MAX_READ_SIZE 131072
250#define DM_CRYPT_DEFAULT_MAX_WRITE_SIZE 131072
251
252static unsigned int max_read_size = 0;
253module_param(max_read_size, uint, 0644);
254MODULE_PARM_DESC(max_read_size, "Maximum size of a read request");
255static unsigned int max_write_size = 0;
256module_param(max_write_size, uint, 0644);
257MODULE_PARM_DESC(max_write_size, "Maximum size of a write request");
258
259static unsigned get_max_request_sectors(struct dm_target *ti, struct bio *bio, bool no_split)
260{
261 struct crypt_config *cc = ti->private;
262 unsigned val, sector_align;
263 bool wrt = op_is_write(bio_op(bio));
264
265 if (no_split) {
266 val = -1;
267 } else if (wrt) {
268 val = min_not_zero(READ_ONCE(max_write_size),
269 DM_CRYPT_DEFAULT_MAX_WRITE_SIZE);
270 } else {
271 val = min_not_zero(READ_ONCE(max_read_size),
272 DM_CRYPT_DEFAULT_MAX_READ_SIZE);
273 }
274
275 if (wrt || cc->used_tag_size)
276 val = min(val, BIO_MAX_VECS << PAGE_SHIFT);
277
278 sector_align = max(bdev_logical_block_size(cc->dev->bdev),
279 (unsigned)cc->sector_size);
280 val = round_down(val, sector_align);
281 if (unlikely(!val))
282 val = sector_align;
283 return val >> SECTOR_SHIFT;
284}
285
286static void crypt_endio(struct bio *clone);
287static void kcryptd_queue_crypt(struct dm_crypt_io *io);
288static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
289 struct scatterlist *sg);
290
291static bool crypt_integrity_aead(struct crypt_config *cc);
292
293/*
294 * Use this to access cipher attributes that are independent of the key.
295 */
296static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
297{
298 return cc->cipher_tfm.tfms[0];
299}
300
301static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
302{
303 return cc->cipher_tfm.tfms_aead[0];
304}
305
306/*
307 * Different IV generation algorithms:
308 *
309 * plain: the initial vector is the 32-bit little-endian version of the sector
310 * number, padded with zeros if necessary.
311 *
312 * plain64: the initial vector is the 64-bit little-endian version of the sector
313 * number, padded with zeros if necessary.
314 *
315 * plain64be: the initial vector is the 64-bit big-endian version of the sector
316 * number, padded with zeros if necessary.
317 *
318 * essiv: "encrypted sector|salt initial vector", the sector number is
319 * encrypted with the bulk cipher using a salt as key. The salt
320 * should be derived from the bulk cipher's key via hashing.
321 *
322 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
323 * (needed for LRW-32-AES and possible other narrow block modes)
324 *
325 * null: the initial vector is always zero. Provides compatibility with
326 * obsolete loop_fish2 devices. Do not use for new devices.
327 *
328 * lmk: Compatible implementation of the block chaining mode used
329 * by the Loop-AES block device encryption system
330 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
331 * It operates on full 512 byte sectors and uses CBC
332 * with an IV derived from the sector number, the data and
333 * optionally extra IV seed.
334 * This means that after decryption the first block
335 * of sector must be tweaked according to decrypted data.
336 * Loop-AES can use three encryption schemes:
337 * version 1: is plain aes-cbc mode
338 * version 2: uses 64 multikey scheme with lmk IV generator
339 * version 3: the same as version 2 with additional IV seed
340 * (it uses 65 keys, last key is used as IV seed)
341 *
342 * tcw: Compatible implementation of the block chaining mode used
343 * by the TrueCrypt device encryption system (prior to version 4.1).
344 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
345 * It operates on full 512 byte sectors and uses CBC
346 * with an IV derived from initial key and the sector number.
347 * In addition, whitening value is applied on every sector, whitening
348 * is calculated from initial key, sector number and mixed using CRC32.
349 * Note that this encryption scheme is vulnerable to watermarking attacks
350 * and should be used for old compatible containers access only.
351 *
352 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
353 * The IV is encrypted little-endian byte-offset (with the same key
354 * and cipher as the volume).
355 *
356 * elephant: The extended version of eboiv with additional Elephant diffuser
357 * used with Bitlocker CBC mode.
358 * This mode was used in older Windows systems
359 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
360 */
361
362static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
363 struct dm_crypt_request *dmreq)
364{
365 memset(iv, 0, cc->iv_size);
366 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
367
368 return 0;
369}
370
371static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
372 struct dm_crypt_request *dmreq)
373{
374 memset(iv, 0, cc->iv_size);
375 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
376
377 return 0;
378}
379
380static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
381 struct dm_crypt_request *dmreq)
382{
383 memset(iv, 0, cc->iv_size);
384 /* iv_size is at least of size u64; usually it is 16 bytes */
385 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
386
387 return 0;
388}
389
390static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
391 struct dm_crypt_request *dmreq)
392{
393 /*
394 * ESSIV encryption of the IV is now handled by the crypto API,
395 * so just pass the plain sector number here.
396 */
397 memset(iv, 0, cc->iv_size);
398 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
399
400 return 0;
401}
402
403static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
404 const char *opts)
405{
406 unsigned int bs;
407 int log;
408
409 if (crypt_integrity_aead(cc))
410 bs = crypto_aead_blocksize(any_tfm_aead(cc));
411 else
412 bs = crypto_skcipher_blocksize(any_tfm(cc));
413 log = ilog2(bs);
414
415 /*
416 * We need to calculate how far we must shift the sector count
417 * to get the cipher block count, we use this shift in _gen.
418 */
419 if (1 << log != bs) {
420 ti->error = "cypher blocksize is not a power of 2";
421 return -EINVAL;
422 }
423
424 if (log > 9) {
425 ti->error = "cypher blocksize is > 512";
426 return -EINVAL;
427 }
428
429 cc->iv_gen_private.benbi.shift = 9 - log;
430
431 return 0;
432}
433
434static void crypt_iv_benbi_dtr(struct crypt_config *cc)
435{
436}
437
438static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
439 struct dm_crypt_request *dmreq)
440{
441 __be64 val;
442
443 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
444
445 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
446 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
447
448 return 0;
449}
450
451static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
452 struct dm_crypt_request *dmreq)
453{
454 memset(iv, 0, cc->iv_size);
455
456 return 0;
457}
458
459static void crypt_iv_lmk_dtr(struct crypt_config *cc)
460{
461 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
462
463 kfree_sensitive(lmk->seed);
464 lmk->seed = NULL;
465}
466
467static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
468 const char *opts)
469{
470 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
471
472 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
473 ti->error = "Unsupported sector size for LMK";
474 return -EINVAL;
475 }
476
477 if (fips_enabled) {
478 ti->error = "LMK support is disabled due to FIPS";
479 /* ... because it uses MD5. */
480 return -EINVAL;
481 }
482
483 /* No seed in LMK version 2 */
484 if (cc->key_parts == cc->tfms_count) {
485 lmk->seed = NULL;
486 return 0;
487 }
488
489 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
490 if (!lmk->seed) {
491 ti->error = "Error kmallocing seed storage in LMK";
492 return -ENOMEM;
493 }
494
495 return 0;
496}
497
498static int crypt_iv_lmk_init(struct crypt_config *cc)
499{
500 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
501 int subkey_size = cc->key_size / cc->key_parts;
502
503 /* LMK seed is on the position of LMK_KEYS + 1 key */
504 if (lmk->seed)
505 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
506 MD5_DIGEST_SIZE);
507
508 return 0;
509}
510
511static void crypt_iv_lmk_wipe(struct crypt_config *cc)
512{
513 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
514
515 if (lmk->seed)
516 memset(lmk->seed, 0, LMK_SEED_SIZE);
517}
518
519static void crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
520 struct dm_crypt_request *dmreq, u8 *data)
521{
522 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
523 struct md5_ctx ctx;
524 __le32 buf[4];
525
526 md5_init(&ctx);
527
528 if (lmk->seed)
529 md5_update(&ctx, lmk->seed, LMK_SEED_SIZE);
530
531 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
532 md5_update(&ctx, data + 16, 16 * 31);
533
534 /* Sector is cropped to 56 bits here */
535 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
536 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
537 buf[2] = cpu_to_le32(4024);
538 buf[3] = 0;
539 md5_update(&ctx, (u8 *)buf, sizeof(buf));
540
541 /* No MD5 padding here */
542 cpu_to_le32_array(ctx.state.h, ARRAY_SIZE(ctx.state.h));
543 memcpy(iv, ctx.state.h, cc->iv_size);
544}
545
546static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
547 struct dm_crypt_request *dmreq)
548{
549 struct scatterlist *sg;
550 u8 *src;
551
552 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
553 sg = crypt_get_sg_data(cc, dmreq->sg_in);
554 src = kmap_local_page(sg_page(sg));
555 crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
556 kunmap_local(src);
557 } else
558 memset(iv, 0, cc->iv_size);
559 return 0;
560}
561
562static void crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
563 struct dm_crypt_request *dmreq)
564{
565 struct scatterlist *sg;
566 u8 *dst;
567
568 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
569 return;
570
571 sg = crypt_get_sg_data(cc, dmreq->sg_out);
572 dst = kmap_local_page(sg_page(sg));
573 crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
574
575 /* Tweak the first block of plaintext sector */
576 crypto_xor(dst + sg->offset, iv, cc->iv_size);
577
578 kunmap_local(dst);
579}
580
581static void crypt_iv_tcw_dtr(struct crypt_config *cc)
582{
583 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
584
585 kfree_sensitive(tcw->iv_seed);
586 tcw->iv_seed = NULL;
587 kfree_sensitive(tcw->whitening);
588 tcw->whitening = NULL;
589}
590
591static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
592 const char *opts)
593{
594 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
595
596 if (cc->sector_size != (1 << SECTOR_SHIFT)) {
597 ti->error = "Unsupported sector size for TCW";
598 return -EINVAL;
599 }
600
601 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
602 ti->error = "Wrong key size for TCW";
603 return -EINVAL;
604 }
605
606 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
607 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
608 if (!tcw->iv_seed || !tcw->whitening) {
609 crypt_iv_tcw_dtr(cc);
610 ti->error = "Error allocating seed storage in TCW";
611 return -ENOMEM;
612 }
613
614 return 0;
615}
616
617static int crypt_iv_tcw_init(struct crypt_config *cc)
618{
619 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
620 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
621
622 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
623 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
624 TCW_WHITENING_SIZE);
625
626 return 0;
627}
628
629static void crypt_iv_tcw_wipe(struct crypt_config *cc)
630{
631 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
632
633 memset(tcw->iv_seed, 0, cc->iv_size);
634 memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
635}
636
637static void crypt_iv_tcw_whitening(struct crypt_config *cc,
638 struct dm_crypt_request *dmreq, u8 *data)
639{
640 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
641 __le64 sector = cpu_to_le64(dmreq->iv_sector);
642 u8 buf[TCW_WHITENING_SIZE];
643 int i;
644
645 /* xor whitening with sector number */
646 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8);
647 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8);
648
649 /* calculate crc32 for every 32bit part and xor it */
650 for (i = 0; i < 4; i++)
651 put_unaligned_le32(crc32(0, &buf[i * 4], 4), &buf[i * 4]);
652 crypto_xor(&buf[0], &buf[12], 4);
653 crypto_xor(&buf[4], &buf[8], 4);
654
655 /* apply whitening (8 bytes) to whole sector */
656 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
657 crypto_xor(data + i * 8, buf, 8);
658 memzero_explicit(buf, sizeof(buf));
659}
660
661static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
662 struct dm_crypt_request *dmreq)
663{
664 struct scatterlist *sg;
665 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
666 __le64 sector = cpu_to_le64(dmreq->iv_sector);
667 u8 *src;
668
669 /* Remove whitening from ciphertext */
670 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
671 sg = crypt_get_sg_data(cc, dmreq->sg_in);
672 src = kmap_local_page(sg_page(sg));
673 crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
674 kunmap_local(src);
675 }
676
677 /* Calculate IV */
678 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8);
679 if (cc->iv_size > 8)
680 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or,
681 cc->iv_size - 8);
682
683 return 0;
684}
685
686static void crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
687 struct dm_crypt_request *dmreq)
688{
689 struct scatterlist *sg;
690 u8 *dst;
691
692 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
693 return;
694
695 /* Apply whitening on ciphertext */
696 sg = crypt_get_sg_data(cc, dmreq->sg_out);
697 dst = kmap_local_page(sg_page(sg));
698 crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
699 kunmap_local(dst);
700}
701
702static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
703 struct dm_crypt_request *dmreq)
704{
705 /* Used only for writes, there must be an additional space to store IV */
706 get_random_bytes(iv, cc->iv_size);
707 return 0;
708}
709
710static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
711 const char *opts)
712{
713 if (crypt_integrity_aead(cc)) {
714 ti->error = "AEAD transforms not supported for EBOIV";
715 return -EINVAL;
716 }
717
718 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
719 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher";
720 return -EINVAL;
721 }
722
723 return 0;
724}
725
726static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
727 struct dm_crypt_request *dmreq)
728{
729 struct crypto_skcipher *tfm = any_tfm(cc);
730 struct skcipher_request *req;
731 struct scatterlist src, dst;
732 DECLARE_CRYPTO_WAIT(wait);
733 unsigned int reqsize;
734 int err;
735 u8 *buf;
736
737 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm);
738 reqsize = ALIGN(reqsize, __alignof__(__le64));
739
740 req = kmalloc(reqsize + cc->iv_size, GFP_NOIO);
741 if (!req)
742 return -ENOMEM;
743
744 skcipher_request_set_tfm(req, tfm);
745
746 buf = (u8 *)req + reqsize;
747 memset(buf, 0, cc->iv_size);
748 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
749
750 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
751 sg_init_one(&dst, iv, cc->iv_size);
752 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
753 skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
754 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
755 kfree_sensitive(req);
756
757 return err;
758}
759
760static void crypt_iv_elephant_dtr(struct crypt_config *cc)
761{
762 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
763
764 kfree_sensitive(elephant->key);
765 elephant->key = NULL;
766}
767
768static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
769 const char *opts)
770{
771 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
772 int r;
773
774 elephant->key = kmalloc_obj(*elephant->key);
775 if (!elephant->key)
776 return -ENOMEM;
777
778 r = crypt_iv_eboiv_ctr(cc, ti, NULL);
779 if (r)
780 crypt_iv_elephant_dtr(cc);
781 return r;
782}
783
784static void diffuser_disk_to_cpu(u32 *d, size_t n)
785{
786#ifndef __LITTLE_ENDIAN
787 int i;
788
789 for (i = 0; i < n; i++)
790 d[i] = le32_to_cpu((__le32)d[i]);
791#endif
792}
793
794static void diffuser_cpu_to_disk(__le32 *d, size_t n)
795{
796#ifndef __LITTLE_ENDIAN
797 int i;
798
799 for (i = 0; i < n; i++)
800 d[i] = cpu_to_le32((u32)d[i]);
801#endif
802}
803
804static void diffuser_a_decrypt(u32 *d, size_t n)
805{
806 int i, i1, i2, i3;
807
808 for (i = 0; i < 5; i++) {
809 i1 = 0;
810 i2 = n - 2;
811 i3 = n - 5;
812
813 while (i1 < (n - 1)) {
814 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
815 i1++; i2++; i3++;
816
817 if (i3 >= n)
818 i3 -= n;
819
820 d[i1] += d[i2] ^ d[i3];
821 i1++; i2++; i3++;
822
823 if (i2 >= n)
824 i2 -= n;
825
826 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
827 i1++; i2++; i3++;
828
829 d[i1] += d[i2] ^ d[i3];
830 i1++; i2++; i3++;
831 }
832 }
833}
834
835static void diffuser_a_encrypt(u32 *d, size_t n)
836{
837 int i, i1, i2, i3;
838
839 for (i = 0; i < 5; i++) {
840 i1 = n - 1;
841 i2 = n - 2 - 1;
842 i3 = n - 5 - 1;
843
844 while (i1 > 0) {
845 d[i1] -= d[i2] ^ d[i3];
846 i1--; i2--; i3--;
847
848 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
849 i1--; i2--; i3--;
850
851 if (i2 < 0)
852 i2 += n;
853
854 d[i1] -= d[i2] ^ d[i3];
855 i1--; i2--; i3--;
856
857 if (i3 < 0)
858 i3 += n;
859
860 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
861 i1--; i2--; i3--;
862 }
863 }
864}
865
866static void diffuser_b_decrypt(u32 *d, size_t n)
867{
868 int i, i1, i2, i3;
869
870 for (i = 0; i < 3; i++) {
871 i1 = 0;
872 i2 = 2;
873 i3 = 5;
874
875 while (i1 < (n - 1)) {
876 d[i1] += d[i2] ^ d[i3];
877 i1++; i2++; i3++;
878
879 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
880 i1++; i2++; i3++;
881
882 if (i2 >= n)
883 i2 -= n;
884
885 d[i1] += d[i2] ^ d[i3];
886 i1++; i2++; i3++;
887
888 if (i3 >= n)
889 i3 -= n;
890
891 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
892 i1++; i2++; i3++;
893 }
894 }
895}
896
897static void diffuser_b_encrypt(u32 *d, size_t n)
898{
899 int i, i1, i2, i3;
900
901 for (i = 0; i < 3; i++) {
902 i1 = n - 1;
903 i2 = 2 - 1;
904 i3 = 5 - 1;
905
906 while (i1 > 0) {
907 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
908 i1--; i2--; i3--;
909
910 if (i3 < 0)
911 i3 += n;
912
913 d[i1] -= d[i2] ^ d[i3];
914 i1--; i2--; i3--;
915
916 if (i2 < 0)
917 i2 += n;
918
919 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
920 i1--; i2--; i3--;
921
922 d[i1] -= d[i2] ^ d[i3];
923 i1--; i2--; i3--;
924 }
925 }
926}
927
928static void crypt_iv_elephant(struct crypt_config *cc,
929 struct dm_crypt_request *dmreq)
930{
931 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
932 u8 *data, *data2, *data_offset;
933 struct scatterlist *sg, *sg2;
934 union {
935 __le64 w[2];
936 u8 b[16];
937 } es;
938 u8 ks[32] __aligned(__alignof(long)); /* Elephant sector key */
939 int i;
940
941 es.w[0] = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
942 es.w[1] = 0;
943
944 /* E(Ks, e(s)) */
945 aes_encrypt(elephant->key, &ks[0], es.b);
946
947 /* E(Ks, e'(s)) */
948 es.b[15] = 0x80;
949 aes_encrypt(elephant->key, &ks[16], es.b);
950
951 sg = crypt_get_sg_data(cc, dmreq->sg_out);
952 data = kmap_local_page(sg_page(sg));
953 data_offset = data + sg->offset;
954
955 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */
956 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
957 sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
958 data2 = kmap_local_page(sg_page(sg2));
959 memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
960 kunmap_local(data2);
961 }
962
963 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
964 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32));
965 diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
966 diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
967 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32));
968 }
969
970 for (i = 0; i < (cc->sector_size / 32); i++)
971 crypto_xor(data_offset + i * 32, ks, 32);
972
973 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
974 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32));
975 diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
976 diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
977 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32));
978 }
979
980 kunmap_local(data);
981 memzero_explicit(ks, sizeof(ks));
982 memzero_explicit(&es, sizeof(es));
983}
984
985static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
986 struct dm_crypt_request *dmreq)
987{
988 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
989 crypt_iv_elephant(cc, dmreq);
990
991 return crypt_iv_eboiv_gen(cc, iv, dmreq);
992}
993
994static void crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
995 struct dm_crypt_request *dmreq)
996{
997 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
998 crypt_iv_elephant(cc, dmreq);
999}
1000
1001static int crypt_iv_elephant_init(struct crypt_config *cc)
1002{
1003 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1004 int key_offset = cc->key_size - cc->key_extra_size;
1005
1006 return aes_prepareenckey(elephant->key, &cc->key[key_offset], cc->key_extra_size);
1007}
1008
1009static void crypt_iv_elephant_wipe(struct crypt_config *cc)
1010{
1011 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1012
1013 memzero_explicit(elephant->key, sizeof(*elephant->key));
1014}
1015
1016static const struct crypt_iv_operations crypt_iv_plain_ops = {
1017 .generator = crypt_iv_plain_gen
1018};
1019
1020static const struct crypt_iv_operations crypt_iv_plain64_ops = {
1021 .generator = crypt_iv_plain64_gen
1022};
1023
1024static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
1025 .generator = crypt_iv_plain64be_gen
1026};
1027
1028static const struct crypt_iv_operations crypt_iv_essiv_ops = {
1029 .generator = crypt_iv_essiv_gen
1030};
1031
1032static const struct crypt_iv_operations crypt_iv_benbi_ops = {
1033 .ctr = crypt_iv_benbi_ctr,
1034 .dtr = crypt_iv_benbi_dtr,
1035 .generator = crypt_iv_benbi_gen
1036};
1037
1038static const struct crypt_iv_operations crypt_iv_null_ops = {
1039 .generator = crypt_iv_null_gen
1040};
1041
1042static const struct crypt_iv_operations crypt_iv_lmk_ops = {
1043 .ctr = crypt_iv_lmk_ctr,
1044 .dtr = crypt_iv_lmk_dtr,
1045 .init = crypt_iv_lmk_init,
1046 .wipe = crypt_iv_lmk_wipe,
1047 .generator = crypt_iv_lmk_gen,
1048 .post = crypt_iv_lmk_post
1049};
1050
1051static const struct crypt_iv_operations crypt_iv_tcw_ops = {
1052 .ctr = crypt_iv_tcw_ctr,
1053 .dtr = crypt_iv_tcw_dtr,
1054 .init = crypt_iv_tcw_init,
1055 .wipe = crypt_iv_tcw_wipe,
1056 .generator = crypt_iv_tcw_gen,
1057 .post = crypt_iv_tcw_post
1058};
1059
1060static const struct crypt_iv_operations crypt_iv_random_ops = {
1061 .generator = crypt_iv_random_gen
1062};
1063
1064static const struct crypt_iv_operations crypt_iv_eboiv_ops = {
1065 .ctr = crypt_iv_eboiv_ctr,
1066 .generator = crypt_iv_eboiv_gen
1067};
1068
1069static const struct crypt_iv_operations crypt_iv_elephant_ops = {
1070 .ctr = crypt_iv_elephant_ctr,
1071 .dtr = crypt_iv_elephant_dtr,
1072 .init = crypt_iv_elephant_init,
1073 .wipe = crypt_iv_elephant_wipe,
1074 .generator = crypt_iv_elephant_gen,
1075 .post = crypt_iv_elephant_post
1076};
1077
1078/*
1079 * Integrity extensions
1080 */
1081static bool crypt_integrity_aead(struct crypt_config *cc)
1082{
1083 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
1084}
1085
1086static bool crypt_integrity_hmac(struct crypt_config *cc)
1087{
1088 return crypt_integrity_aead(cc) && cc->key_mac_size;
1089}
1090
1091/* Get sg containing data */
1092static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
1093 struct scatterlist *sg)
1094{
1095 if (unlikely(crypt_integrity_aead(cc)))
1096 return &sg[2];
1097
1098 return sg;
1099}
1100
1101static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
1102{
1103 struct bio_integrity_payload *bip;
1104 unsigned int tag_len;
1105 int ret;
1106
1107 if (!bio_sectors(bio) || !io->cc->tuple_size)
1108 return 0;
1109
1110 bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
1111 if (IS_ERR(bip))
1112 return PTR_ERR(bip);
1113
1114 tag_len = io->cc->tuple_size * (bio_sectors(bio) >> io->cc->sector_shift);
1115
1116 bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
1117
1118 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
1119 tag_len, offset_in_page(io->integrity_metadata));
1120 if (unlikely(ret != tag_len))
1121 return -ENOMEM;
1122
1123 return 0;
1124}
1125
1126static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
1127{
1128#ifdef CONFIG_BLK_DEV_INTEGRITY
1129 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
1130 struct mapped_device *md = dm_table_get_md(ti->table);
1131
1132 /* We require an underlying device with non-PI metadata */
1133 if (!bi || bi->csum_type != BLK_INTEGRITY_CSUM_NONE) {
1134 ti->error = "Integrity profile not supported.";
1135 return -EINVAL;
1136 }
1137
1138 if (bi->metadata_size < cc->used_tag_size) {
1139 ti->error = "Integrity profile tag size mismatch.";
1140 return -EINVAL;
1141 }
1142 cc->tuple_size = bi->metadata_size;
1143 if (1 << bi->interval_exp != cc->sector_size) {
1144 ti->error = "Integrity profile sector size mismatch.";
1145 return -EINVAL;
1146 }
1147
1148 if (crypt_integrity_aead(cc)) {
1149 cc->integrity_tag_size = cc->used_tag_size - cc->integrity_iv_size;
1150 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
1151 cc->integrity_tag_size, cc->integrity_iv_size);
1152
1153 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
1154 ti->error = "Integrity AEAD auth tag size is not supported.";
1155 return -EINVAL;
1156 }
1157 } else if (cc->integrity_iv_size)
1158 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
1159 cc->integrity_iv_size);
1160
1161 if ((cc->integrity_tag_size + cc->integrity_iv_size) > cc->tuple_size) {
1162 ti->error = "Not enough space for integrity tag in the profile.";
1163 return -EINVAL;
1164 }
1165
1166 return 0;
1167#else
1168 ti->error = "Integrity profile not supported.";
1169 return -EINVAL;
1170#endif
1171}
1172
1173static void crypt_convert_init(struct crypt_config *cc,
1174 struct convert_context *ctx,
1175 struct bio *bio_out, struct bio *bio_in,
1176 sector_t sector)
1177{
1178 ctx->bio_in = bio_in;
1179 ctx->bio_out = bio_out;
1180 if (bio_in)
1181 ctx->iter_in = bio_in->bi_iter;
1182 if (bio_out)
1183 ctx->iter_out = bio_out->bi_iter;
1184 ctx->cc_sector = sector + cc->iv_offset;
1185 ctx->tag_offset = 0;
1186 init_completion(&ctx->restart);
1187}
1188
1189static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1190 void *req)
1191{
1192 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1193}
1194
1195static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1196{
1197 return (void *)((char *)dmreq - cc->dmreq_start);
1198}
1199
1200static u8 *iv_of_dmreq(struct crypt_config *cc,
1201 struct dm_crypt_request *dmreq)
1202{
1203 if (crypt_integrity_aead(cc))
1204 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1205 crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1206 else
1207 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1208 crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1209}
1210
1211static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1212 struct dm_crypt_request *dmreq)
1213{
1214 return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1215}
1216
1217static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
1218 struct dm_crypt_request *dmreq)
1219{
1220 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
1221
1222 return (__le64 *) ptr;
1223}
1224
1225static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1226 struct dm_crypt_request *dmreq)
1227{
1228 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1229 cc->iv_size + sizeof(uint64_t);
1230
1231 return (unsigned int *)ptr;
1232}
1233
1234static void *tag_from_dmreq(struct crypt_config *cc,
1235 struct dm_crypt_request *dmreq)
1236{
1237 struct convert_context *ctx = dmreq->ctx;
1238 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1239
1240 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1241 cc->tuple_size];
1242}
1243
1244static void *iv_tag_from_dmreq(struct crypt_config *cc,
1245 struct dm_crypt_request *dmreq)
1246{
1247 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1248}
1249
1250static int crypt_convert_block_aead(struct crypt_config *cc,
1251 struct convert_context *ctx,
1252 struct aead_request *req,
1253 unsigned int tag_offset)
1254{
1255 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1256 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1257 struct dm_crypt_request *dmreq;
1258 u8 *iv, *org_iv, *tag_iv, *tag;
1259 __le64 *sector;
1260 int r = 0;
1261
1262 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1263
1264 /* Reject unexpected unaligned bio. */
1265 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1266 return -EIO;
1267
1268 dmreq = dmreq_of_req(cc, req);
1269 dmreq->iv_sector = ctx->cc_sector;
1270 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1271 dmreq->iv_sector >>= cc->sector_shift;
1272 dmreq->ctx = ctx;
1273
1274 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1275
1276 sector = org_sector_of_dmreq(cc, dmreq);
1277 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1278
1279 iv = iv_of_dmreq(cc, dmreq);
1280 org_iv = org_iv_of_dmreq(cc, dmreq);
1281 tag = tag_from_dmreq(cc, dmreq);
1282 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1283
1284 /* AEAD request:
1285 * |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1286 * | (authenticated) | (auth+encryption) | |
1287 * | sector_LE | IV | sector in/out | tag in/out |
1288 */
1289 sg_init_table(dmreq->sg_in, 4);
1290 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1291 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1292 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1293 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1294
1295 sg_init_table(dmreq->sg_out, 4);
1296 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1297 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1298 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1299 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1300
1301 if (cc->iv_gen_ops) {
1302 /* For READs use IV stored in integrity metadata */
1303 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1304 memcpy(org_iv, tag_iv, cc->iv_size);
1305 } else {
1306 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1307 if (r < 0)
1308 return r;
1309 /* Store generated IV in integrity metadata */
1310 if (cc->integrity_iv_size)
1311 memcpy(tag_iv, org_iv, cc->iv_size);
1312 }
1313 /* Working copy of IV, to be modified in crypto API */
1314 memcpy(iv, org_iv, cc->iv_size);
1315 }
1316
1317 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1318 if (bio_data_dir(ctx->bio_in) == WRITE) {
1319 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1320 cc->sector_size, iv);
1321 r = crypto_aead_encrypt(req);
1322 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->tuple_size)
1323 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1324 cc->tuple_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1325 } else {
1326 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1327 cc->sector_size + cc->integrity_tag_size, iv);
1328 r = crypto_aead_decrypt(req);
1329 }
1330
1331 if (r == -EBADMSG) {
1332 sector_t s = le64_to_cpu(*sector);
1333
1334 ctx->aead_failed = true;
1335 if (ctx->aead_recheck) {
1336 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
1337 ctx->bio_in->bi_bdev, s);
1338 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
1339 ctx->bio_in, s, 0);
1340 }
1341 }
1342
1343 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1344 cc->iv_gen_ops->post(cc, org_iv, dmreq);
1345
1346 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1347 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1348
1349 return r;
1350}
1351
1352static int crypt_convert_block_skcipher(struct crypt_config *cc,
1353 struct convert_context *ctx,
1354 struct skcipher_request *req,
1355 unsigned int tag_offset)
1356{
1357 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1358 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1359 struct scatterlist *sg_in, *sg_out;
1360 struct dm_crypt_request *dmreq;
1361 u8 *iv, *org_iv, *tag_iv;
1362 __le64 *sector;
1363 int r = 0;
1364
1365 /* Reject unexpected unaligned bio. */
1366 if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1367 return -EIO;
1368
1369 dmreq = dmreq_of_req(cc, req);
1370 dmreq->iv_sector = ctx->cc_sector;
1371 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1372 dmreq->iv_sector >>= cc->sector_shift;
1373 dmreq->ctx = ctx;
1374
1375 *org_tag_of_dmreq(cc, dmreq) = tag_offset;
1376
1377 iv = iv_of_dmreq(cc, dmreq);
1378 org_iv = org_iv_of_dmreq(cc, dmreq);
1379 tag_iv = iv_tag_from_dmreq(cc, dmreq);
1380
1381 sector = org_sector_of_dmreq(cc, dmreq);
1382 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1383
1384 /* For skcipher we use only the first sg item */
1385 sg_in = &dmreq->sg_in[0];
1386 sg_out = &dmreq->sg_out[0];
1387
1388 sg_init_table(sg_in, 1);
1389 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1390
1391 sg_init_table(sg_out, 1);
1392 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1393
1394 if (cc->iv_gen_ops) {
1395 /* For READs use IV stored in integrity metadata */
1396 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1397 memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1398 } else {
1399 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1400 if (r < 0)
1401 return r;
1402 /* Data can be already preprocessed in generator */
1403 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
1404 sg_in = sg_out;
1405 /* Store generated IV in integrity metadata */
1406 if (cc->integrity_iv_size)
1407 memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1408 }
1409 /* Working copy of IV, to be modified in crypto API */
1410 memcpy(iv, org_iv, cc->iv_size);
1411 }
1412
1413 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1414
1415 if (bio_data_dir(ctx->bio_in) == WRITE)
1416 r = crypto_skcipher_encrypt(req);
1417 else
1418 r = crypto_skcipher_decrypt(req);
1419
1420 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1421 cc->iv_gen_ops->post(cc, org_iv, dmreq);
1422
1423 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1424 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1425
1426 return r;
1427}
1428
1429static void kcryptd_async_done(void *async_req, int error);
1430
1431static int crypt_alloc_req_skcipher(struct crypt_config *cc,
1432 struct convert_context *ctx)
1433{
1434 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1);
1435
1436 if (!ctx->r.req) {
1437 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1438 if (!ctx->r.req)
1439 return -ENOMEM;
1440 }
1441
1442 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1443
1444 /*
1445 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1446 * requests if driver request queue is full.
1447 */
1448 skcipher_request_set_callback(ctx->r.req,
1449 CRYPTO_TFM_REQ_MAY_BACKLOG,
1450 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
1451
1452 return 0;
1453}
1454
1455static int crypt_alloc_req_aead(struct crypt_config *cc,
1456 struct convert_context *ctx)
1457{
1458 if (!ctx->r.req_aead) {
1459 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1460 if (!ctx->r.req_aead)
1461 return -ENOMEM;
1462 }
1463
1464 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1465
1466 /*
1467 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1468 * requests if driver request queue is full.
1469 */
1470 aead_request_set_callback(ctx->r.req_aead,
1471 CRYPTO_TFM_REQ_MAY_BACKLOG,
1472 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
1473
1474 return 0;
1475}
1476
1477static int crypt_alloc_req(struct crypt_config *cc,
1478 struct convert_context *ctx)
1479{
1480 if (crypt_integrity_aead(cc))
1481 return crypt_alloc_req_aead(cc, ctx);
1482 else
1483 return crypt_alloc_req_skcipher(cc, ctx);
1484}
1485
1486static void crypt_free_req_skcipher(struct crypt_config *cc,
1487 struct skcipher_request *req, struct bio *base_bio)
1488{
1489 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1490
1491 if ((struct skcipher_request *)(io + 1) != req)
1492 mempool_free(req, &cc->req_pool);
1493}
1494
1495static void crypt_free_req_aead(struct crypt_config *cc,
1496 struct aead_request *req, struct bio *base_bio)
1497{
1498 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1499
1500 if ((struct aead_request *)(io + 1) != req)
1501 mempool_free(req, &cc->req_pool);
1502}
1503
1504static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1505{
1506 if (crypt_integrity_aead(cc))
1507 crypt_free_req_aead(cc, req, base_bio);
1508 else
1509 crypt_free_req_skcipher(cc, req, base_bio);
1510}
1511
1512/*
1513 * Encrypt / decrypt data from one bio to another one (can be the same one)
1514 */
1515static blk_status_t crypt_convert(struct crypt_config *cc,
1516 struct convert_context *ctx, bool atomic, bool reset_pending)
1517{
1518 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1519 int r;
1520
1521 /*
1522 * if reset_pending is set we are dealing with the bio for the first time,
1523 * else we're continuing to work on the previous bio, so don't mess with
1524 * the cc_pending counter
1525 */
1526 if (reset_pending)
1527 atomic_set(&ctx->cc_pending, 1);
1528
1529 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1530
1531 r = crypt_alloc_req(cc, ctx);
1532 if (r) {
1533 complete(&ctx->restart);
1534 return BLK_STS_DEV_RESOURCE;
1535 }
1536
1537 atomic_inc(&ctx->cc_pending);
1538
1539 if (crypt_integrity_aead(cc))
1540 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, ctx->tag_offset);
1541 else
1542 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, ctx->tag_offset);
1543
1544 switch (r) {
1545 /*
1546 * The request was queued by a crypto driver
1547 * but the driver request queue is full, let's wait.
1548 */
1549 case -EBUSY:
1550 if (in_interrupt()) {
1551 if (try_wait_for_completion(&ctx->restart)) {
1552 /*
1553 * we don't have to block to wait for completion,
1554 * so proceed
1555 */
1556 } else {
1557 /*
1558 * we can't wait for completion without blocking
1559 * exit and continue processing in a workqueue
1560 */
1561 ctx->r.req = NULL;
1562 ctx->tag_offset++;
1563 ctx->cc_sector += sector_step;
1564 return BLK_STS_DEV_RESOURCE;
1565 }
1566 } else {
1567 wait_for_completion(&ctx->restart);
1568 }
1569 reinit_completion(&ctx->restart);
1570 fallthrough;
1571 /*
1572 * The request is queued and processed asynchronously,
1573 * completion function kcryptd_async_done() will be called.
1574 */
1575 case -EINPROGRESS:
1576 ctx->r.req = NULL;
1577 ctx->tag_offset++;
1578 ctx->cc_sector += sector_step;
1579 continue;
1580 /*
1581 * The request was already processed (synchronously).
1582 */
1583 case 0:
1584 atomic_dec(&ctx->cc_pending);
1585 ctx->cc_sector += sector_step;
1586 ctx->tag_offset++;
1587 if (!atomic)
1588 cond_resched();
1589 continue;
1590 /*
1591 * There was a data integrity error.
1592 */
1593 case -EBADMSG:
1594 atomic_dec(&ctx->cc_pending);
1595 return BLK_STS_PROTECTION;
1596 /*
1597 * There was an error while processing the request.
1598 */
1599 default:
1600 atomic_dec(&ctx->cc_pending);
1601 return BLK_STS_IOERR;
1602 }
1603 }
1604
1605 return 0;
1606}
1607
1608static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1609
1610/*
1611 * Generate a new unfragmented bio with the given size
1612 * This should never violate the device limitations (but if it did then block
1613 * core should split the bio as needed).
1614 *
1615 * This function may be called concurrently. If we allocate from the mempool
1616 * concurrently, there is a possibility of deadlock. For example, if we have
1617 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1618 * the mempool concurrently, it may deadlock in a situation where both processes
1619 * have allocated 128 pages and the mempool is exhausted.
1620 *
1621 * In order to avoid this scenario we allocate the pages under a mutex.
1622 *
1623 * In order to not degrade performance with excessive locking, we try
1624 * non-blocking allocations without a mutex first but on failure we fallback
1625 * to blocking allocations with a mutex.
1626 *
1627 * In order to reduce allocation overhead, we try to allocate compound pages in
1628 * the first pass. If they are not available, we fall back to the mempool.
1629 */
1630static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size)
1631{
1632 struct crypt_config *cc = io->cc;
1633 struct bio *clone;
1634 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1635 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1636 unsigned int remaining_size;
1637 unsigned int order = MAX_PAGE_ORDER;
1638
1639retry:
1640 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1641 mutex_lock(&cc->bio_alloc_lock);
1642
1643 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf,
1644 GFP_NOIO, &cc->bs);
1645 clone->bi_private = io;
1646 clone->bi_end_io = crypt_endio;
1647 clone->bi_ioprio = io->base_bio->bi_ioprio;
1648 clone->bi_iter.bi_sector = cc->start + io->sector;
1649
1650 remaining_size = size;
1651
1652 while (remaining_size) {
1653 struct page *pages;
1654 unsigned size_to_add;
1655 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT);
1656 order = min(order, remaining_order);
1657
1658 while (order > 0) {
1659 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) +
1660 (1 << order) > dm_crypt_pages_per_client))
1661 goto decrease_order;
1662 pages = alloc_pages(gfp_mask
1663 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP,
1664 order);
1665 if (likely(pages != NULL)) {
1666 percpu_counter_add(&cc->n_allocated_pages, 1 << order);
1667 goto have_pages;
1668 }
1669decrease_order:
1670 order--;
1671 }
1672
1673 pages = mempool_alloc(&cc->page_pool, gfp_mask);
1674 if (!pages) {
1675 crypt_free_buffer_pages(cc, clone);
1676 bio_put(clone);
1677 gfp_mask |= __GFP_DIRECT_RECLAIM;
1678 order = 0;
1679 goto retry;
1680 }
1681
1682have_pages:
1683 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size);
1684 __bio_add_page(clone, pages, size_to_add, 0);
1685 remaining_size -= size_to_add;
1686 }
1687
1688 /* Allocate space for integrity tags */
1689 if (dm_crypt_integrity_io_alloc(io, clone)) {
1690 crypt_free_buffer_pages(cc, clone);
1691 bio_put(clone);
1692 clone = NULL;
1693 }
1694
1695 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1696 mutex_unlock(&cc->bio_alloc_lock);
1697
1698 return clone;
1699}
1700
1701static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1702{
1703 struct folio_iter fi;
1704
1705 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */
1706 bio_for_each_folio_all(fi, clone) {
1707 if (folio_test_large(fi.folio)) {
1708 percpu_counter_sub(&cc->n_allocated_pages,
1709 folio_nr_pages(fi.folio));
1710 folio_put(fi.folio);
1711 } else {
1712 mempool_free(&fi.folio->page, &cc->page_pool);
1713 }
1714 }
1715 }
1716}
1717
1718static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1719 struct bio *bio, sector_t sector)
1720{
1721 io->cc = cc;
1722 io->base_bio = bio;
1723 io->sector = sector;
1724 io->error = 0;
1725 io->ctx.aead_recheck = false;
1726 io->ctx.aead_failed = false;
1727 io->ctx.r.req = NULL;
1728 io->integrity_metadata = NULL;
1729 io->integrity_metadata_from_pool = false;
1730 atomic_set(&io->io_pending, 0);
1731}
1732
1733static void crypt_inc_pending(struct dm_crypt_io *io)
1734{
1735 atomic_inc(&io->io_pending);
1736}
1737
1738static void kcryptd_queue_read(struct dm_crypt_io *io);
1739
1740/*
1741 * One of the bios was finished. Check for completion of
1742 * the whole request and correctly clean up the buffer.
1743 */
1744static void crypt_dec_pending(struct dm_crypt_io *io)
1745{
1746 struct crypt_config *cc = io->cc;
1747 struct bio *base_bio = io->base_bio;
1748 blk_status_t error = io->error;
1749
1750 if (!atomic_dec_and_test(&io->io_pending))
1751 return;
1752
1753 if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) &&
1754 cc->used_tag_size && bio_data_dir(base_bio) == READ) {
1755 io->ctx.aead_recheck = true;
1756 io->ctx.aead_failed = false;
1757 io->error = 0;
1758 kcryptd_queue_read(io);
1759 return;
1760 }
1761
1762 if (io->ctx.r.req)
1763 crypt_free_req(cc, io->ctx.r.req, base_bio);
1764
1765 if (unlikely(io->integrity_metadata_from_pool))
1766 mempool_free(io->integrity_metadata, &io->cc->tag_pool);
1767 else
1768 kfree(io->integrity_metadata);
1769
1770 base_bio->bi_status = error;
1771
1772 bio_endio(base_bio);
1773}
1774
1775/*
1776 * kcryptd/kcryptd_io:
1777 *
1778 * Needed because it would be very unwise to do decryption in an
1779 * interrupt context.
1780 *
1781 * kcryptd performs the actual encryption or decryption.
1782 *
1783 * kcryptd_io performs the IO submission.
1784 *
1785 * They must be separated as otherwise the final stages could be
1786 * starved by new requests which can block in the first stages due
1787 * to memory allocation.
1788 *
1789 * The work is done per CPU global for all dm-crypt instances.
1790 * They should not depend on each other and do not block.
1791 */
1792static void crypt_endio(struct bio *clone)
1793{
1794 struct dm_crypt_io *io = clone->bi_private;
1795 struct crypt_config *cc = io->cc;
1796 unsigned int rw = bio_data_dir(clone);
1797 blk_status_t error = clone->bi_status;
1798
1799 if (io->ctx.aead_recheck && !error) {
1800 kcryptd_queue_crypt(io);
1801 return;
1802 }
1803
1804 /*
1805 * free the processed pages
1806 */
1807 if (rw == WRITE || io->ctx.aead_recheck)
1808 crypt_free_buffer_pages(cc, clone);
1809
1810 bio_put(clone);
1811
1812 if (rw == READ && !error) {
1813 kcryptd_queue_crypt(io);
1814 return;
1815 }
1816
1817 if (unlikely(error))
1818 io->error = error;
1819
1820 crypt_dec_pending(io);
1821}
1822
1823#define CRYPT_MAP_READ_GFP GFP_NOWAIT
1824
1825static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1826{
1827 struct crypt_config *cc = io->cc;
1828 struct bio *clone;
1829
1830 if (io->ctx.aead_recheck) {
1831 if (!(gfp & __GFP_DIRECT_RECLAIM))
1832 return 1;
1833 crypt_inc_pending(io);
1834 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1835 if (unlikely(!clone)) {
1836 crypt_dec_pending(io);
1837 return 1;
1838 }
1839 crypt_convert_init(cc, &io->ctx, clone, clone, io->sector);
1840 io->saved_bi_iter = clone->bi_iter;
1841 dm_submit_bio_remap(io->base_bio, clone);
1842 return 0;
1843 }
1844
1845 /*
1846 * We need the original biovec array in order to decrypt the whole bio
1847 * data *afterwards* -- thanks to immutable biovecs we don't need to
1848 * worry about the block layer modifying the biovec array; so leverage
1849 * bio_alloc_clone().
1850 */
1851 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs);
1852 if (!clone)
1853 return 1;
1854
1855 clone->bi_iter.bi_sector = cc->start + io->sector;
1856 clone->bi_private = io;
1857 clone->bi_end_io = crypt_endio;
1858
1859 crypt_inc_pending(io);
1860
1861 if (dm_crypt_integrity_io_alloc(io, clone)) {
1862 crypt_dec_pending(io);
1863 bio_put(clone);
1864 return 1;
1865 }
1866
1867 dm_submit_bio_remap(io->base_bio, clone);
1868 return 0;
1869}
1870
1871static void kcryptd_io_read_work(struct work_struct *work)
1872{
1873 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1874
1875 crypt_inc_pending(io);
1876 if (kcryptd_io_read(io, GFP_NOIO))
1877 io->error = BLK_STS_RESOURCE;
1878 crypt_dec_pending(io);
1879}
1880
1881static void kcryptd_queue_read(struct dm_crypt_io *io)
1882{
1883 struct crypt_config *cc = io->cc;
1884
1885 INIT_WORK(&io->work, kcryptd_io_read_work);
1886 queue_work(cc->io_queue, &io->work);
1887}
1888
1889static void kcryptd_io_write(struct dm_crypt_io *io)
1890{
1891 struct bio *clone = io->ctx.bio_out;
1892
1893 dm_submit_bio_remap(io->base_bio, clone);
1894}
1895
1896#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1897
1898static int dmcrypt_write(void *data)
1899{
1900 struct crypt_config *cc = data;
1901 struct dm_crypt_io *io;
1902
1903 while (1) {
1904 struct rb_root write_tree;
1905 struct blk_plug plug;
1906
1907 spin_lock_irq(&cc->write_thread_lock);
1908continue_locked:
1909
1910 if (!RB_EMPTY_ROOT(&cc->write_tree))
1911 goto pop_from_list;
1912
1913 set_current_state(TASK_INTERRUPTIBLE);
1914
1915 spin_unlock_irq(&cc->write_thread_lock);
1916
1917 if (unlikely(kthread_should_stop())) {
1918 set_current_state(TASK_RUNNING);
1919 break;
1920 }
1921
1922 schedule();
1923
1924 spin_lock_irq(&cc->write_thread_lock);
1925 goto continue_locked;
1926
1927pop_from_list:
1928 write_tree = cc->write_tree;
1929 cc->write_tree = RB_ROOT;
1930 spin_unlock_irq(&cc->write_thread_lock);
1931
1932 BUG_ON(rb_parent(write_tree.rb_node));
1933
1934 /*
1935 * Note: we cannot walk the tree here with rb_next because
1936 * the structures may be freed when kcryptd_io_write is called.
1937 */
1938 blk_start_plug(&plug);
1939 do {
1940 io = crypt_io_from_node(rb_first(&write_tree));
1941 rb_erase(&io->rb_node, &write_tree);
1942 kcryptd_io_write(io);
1943 cond_resched();
1944 } while (!RB_EMPTY_ROOT(&write_tree));
1945 blk_finish_plug(&plug);
1946 }
1947 return 0;
1948}
1949
1950static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1951{
1952 struct bio *clone = io->ctx.bio_out;
1953 struct crypt_config *cc = io->cc;
1954 unsigned long flags;
1955 sector_t sector;
1956 struct rb_node **rbp, *parent;
1957
1958 if (unlikely(io->error)) {
1959 crypt_free_buffer_pages(cc, clone);
1960 bio_put(clone);
1961 crypt_dec_pending(io);
1962 return;
1963 }
1964
1965 /* crypt_convert should have filled the clone bio */
1966 BUG_ON(io->ctx.iter_out.bi_size);
1967
1968 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
1969 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
1970 dm_submit_bio_remap(io->base_bio, clone);
1971 return;
1972 }
1973
1974 spin_lock_irqsave(&cc->write_thread_lock, flags);
1975 if (RB_EMPTY_ROOT(&cc->write_tree))
1976 wake_up_process(cc->write_thread);
1977 rbp = &cc->write_tree.rb_node;
1978 parent = NULL;
1979 sector = io->sector;
1980 while (*rbp) {
1981 parent = *rbp;
1982 if (sector < crypt_io_from_node(parent)->sector)
1983 rbp = &(*rbp)->rb_left;
1984 else
1985 rbp = &(*rbp)->rb_right;
1986 }
1987 rb_link_node(&io->rb_node, parent, rbp);
1988 rb_insert_color(&io->rb_node, &cc->write_tree);
1989 spin_unlock_irqrestore(&cc->write_thread_lock, flags);
1990}
1991
1992static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
1993 struct convert_context *ctx)
1994
1995{
1996 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
1997 return false;
1998
1999 /*
2000 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
2001 * constraints so they do not need to be issued inline by
2002 * kcryptd_crypt_write_convert().
2003 */
2004 switch (bio_op(ctx->bio_in)) {
2005 case REQ_OP_WRITE:
2006 case REQ_OP_WRITE_ZEROES:
2007 return true;
2008 default:
2009 return false;
2010 }
2011}
2012
2013static void kcryptd_crypt_write_continue(struct work_struct *work)
2014{
2015 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2016 struct crypt_config *cc = io->cc;
2017 struct convert_context *ctx = &io->ctx;
2018 int crypt_finished;
2019 blk_status_t r;
2020
2021 wait_for_completion(&ctx->restart);
2022 reinit_completion(&ctx->restart);
2023
2024 r = crypt_convert(cc, &io->ctx, false, false);
2025 if (r)
2026 io->error = r;
2027 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2028 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2029 /* Wait for completion signaled by kcryptd_async_done() */
2030 wait_for_completion(&ctx->restart);
2031 crypt_finished = 1;
2032 }
2033
2034 /* Encryption was already finished, submit io now */
2035 if (crypt_finished)
2036 kcryptd_crypt_write_io_submit(io, 0);
2037
2038 crypt_dec_pending(io);
2039}
2040
2041static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
2042{
2043 struct crypt_config *cc = io->cc;
2044 struct convert_context *ctx = &io->ctx;
2045 struct bio *clone;
2046 int crypt_finished;
2047 blk_status_t r;
2048
2049 /*
2050 * Prevent io from disappearing until this function completes.
2051 */
2052 crypt_inc_pending(io);
2053 crypt_convert_init(cc, ctx, NULL, io->base_bio, io->sector);
2054
2055 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
2056 if (unlikely(!clone)) {
2057 io->error = BLK_STS_IOERR;
2058 goto dec;
2059 }
2060
2061 io->ctx.bio_out = clone;
2062 io->ctx.iter_out = clone->bi_iter;
2063
2064 if (crypt_integrity_aead(cc)) {
2065 bio_copy_data(clone, io->base_bio);
2066 io->ctx.bio_in = clone;
2067 io->ctx.iter_in = clone->bi_iter;
2068 }
2069
2070 crypt_inc_pending(io);
2071 r = crypt_convert(cc, ctx,
2072 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true);
2073 /*
2074 * Crypto API backlogged the request, because its queue was full
2075 * and we're in softirq context, so continue from a workqueue
2076 * (TODO: is it actually possible to be in softirq in the write path?)
2077 */
2078 if (r == BLK_STS_DEV_RESOURCE) {
2079 INIT_WORK(&io->work, kcryptd_crypt_write_continue);
2080 queue_work(cc->crypt_queue, &io->work);
2081 return;
2082 }
2083 if (r)
2084 io->error = r;
2085 crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2086 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2087 /* Wait for completion signaled by kcryptd_async_done() */
2088 wait_for_completion(&ctx->restart);
2089 crypt_finished = 1;
2090 }
2091
2092 /* Encryption was already finished, submit io now */
2093 if (crypt_finished)
2094 kcryptd_crypt_write_io_submit(io, 0);
2095
2096dec:
2097 crypt_dec_pending(io);
2098}
2099
2100static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
2101{
2102 if (io->ctx.aead_recheck) {
2103 if (!io->error) {
2104 io->ctx.bio_in->bi_iter = io->saved_bi_iter;
2105 bio_copy_data(io->base_bio, io->ctx.bio_in);
2106 }
2107 crypt_free_buffer_pages(io->cc, io->ctx.bio_in);
2108 bio_put(io->ctx.bio_in);
2109 }
2110 crypt_dec_pending(io);
2111}
2112
2113static void kcryptd_crypt_read_continue(struct work_struct *work)
2114{
2115 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2116 struct crypt_config *cc = io->cc;
2117 blk_status_t r;
2118
2119 wait_for_completion(&io->ctx.restart);
2120 reinit_completion(&io->ctx.restart);
2121
2122 r = crypt_convert(cc, &io->ctx, false, false);
2123 if (r)
2124 io->error = r;
2125
2126 if (atomic_dec_and_test(&io->ctx.cc_pending))
2127 kcryptd_crypt_read_done(io);
2128
2129 crypt_dec_pending(io);
2130}
2131
2132static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
2133{
2134 struct crypt_config *cc = io->cc;
2135 blk_status_t r;
2136
2137 crypt_inc_pending(io);
2138
2139 if (io->ctx.aead_recheck) {
2140 r = crypt_convert(cc, &io->ctx,
2141 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2142 } else {
2143 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
2144 io->sector);
2145
2146 r = crypt_convert(cc, &io->ctx,
2147 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2148 }
2149 /*
2150 * Crypto API backlogged the request, because its queue was full
2151 * and we're in softirq context, so continue from a workqueue
2152 */
2153 if (r == BLK_STS_DEV_RESOURCE) {
2154 INIT_WORK(&io->work, kcryptd_crypt_read_continue);
2155 queue_work(cc->crypt_queue, &io->work);
2156 return;
2157 }
2158 if (r)
2159 io->error = r;
2160
2161 if (atomic_dec_and_test(&io->ctx.cc_pending))
2162 kcryptd_crypt_read_done(io);
2163
2164 crypt_dec_pending(io);
2165}
2166
2167static void kcryptd_async_done(void *data, int error)
2168{
2169 struct dm_crypt_request *dmreq = data;
2170 struct convert_context *ctx = dmreq->ctx;
2171 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
2172 struct crypt_config *cc = io->cc;
2173
2174 /*
2175 * A request from crypto driver backlog is going to be processed now,
2176 * finish the completion and continue in crypt_convert().
2177 * (Callback will be called for the second time for this request.)
2178 */
2179 if (error == -EINPROGRESS) {
2180 complete(&ctx->restart);
2181 return;
2182 }
2183
2184 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
2185 cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
2186
2187 if (error == -EBADMSG) {
2188 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq));
2189
2190 ctx->aead_failed = true;
2191 if (ctx->aead_recheck) {
2192 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
2193 ctx->bio_in->bi_bdev, s);
2194 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
2195 ctx->bio_in, s, 0);
2196 }
2197 io->error = BLK_STS_PROTECTION;
2198 } else if (error < 0)
2199 io->error = BLK_STS_IOERR;
2200
2201 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
2202
2203 if (!atomic_dec_and_test(&ctx->cc_pending))
2204 return;
2205
2206 /*
2207 * The request is fully completed: for inline writes, let
2208 * kcryptd_crypt_write_convert() do the IO submission.
2209 */
2210 if (bio_data_dir(io->base_bio) == READ) {
2211 kcryptd_crypt_read_done(io);
2212 return;
2213 }
2214
2215 if (kcryptd_crypt_write_inline(cc, ctx)) {
2216 complete(&ctx->restart);
2217 return;
2218 }
2219
2220 kcryptd_crypt_write_io_submit(io, 1);
2221}
2222
2223static void kcryptd_crypt(struct work_struct *work)
2224{
2225 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2226
2227 if (bio_data_dir(io->base_bio) == READ)
2228 kcryptd_crypt_read_convert(io);
2229 else
2230 kcryptd_crypt_write_convert(io);
2231}
2232
2233static void kcryptd_queue_crypt(struct dm_crypt_io *io)
2234{
2235 struct crypt_config *cc = io->cc;
2236
2237 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
2238 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
2239 /*
2240 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context.
2241 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but
2242 * it is being executed with irqs disabled.
2243 */
2244 if (in_hardirq() || irqs_disabled()) {
2245 INIT_WORK(&io->work, kcryptd_crypt);
2246 queue_work(system_bh_wq, &io->work);
2247 return;
2248 } else {
2249 kcryptd_crypt(&io->work);
2250 return;
2251 }
2252 }
2253
2254 INIT_WORK(&io->work, kcryptd_crypt);
2255 queue_work(cc->crypt_queue, &io->work);
2256}
2257
2258static void crypt_free_tfms_aead(struct crypt_config *cc)
2259{
2260 if (!cc->cipher_tfm.tfms_aead)
2261 return;
2262
2263 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2264 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
2265 cc->cipher_tfm.tfms_aead[0] = NULL;
2266 }
2267
2268 kfree(cc->cipher_tfm.tfms_aead);
2269 cc->cipher_tfm.tfms_aead = NULL;
2270}
2271
2272static void crypt_free_tfms_skcipher(struct crypt_config *cc)
2273{
2274 unsigned int i;
2275
2276 if (!cc->cipher_tfm.tfms)
2277 return;
2278
2279 for (i = 0; i < cc->tfms_count; i++)
2280 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
2281 crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
2282 cc->cipher_tfm.tfms[i] = NULL;
2283 }
2284
2285 kfree(cc->cipher_tfm.tfms);
2286 cc->cipher_tfm.tfms = NULL;
2287}
2288
2289static void crypt_free_tfms(struct crypt_config *cc)
2290{
2291 if (crypt_integrity_aead(cc))
2292 crypt_free_tfms_aead(cc);
2293 else
2294 crypt_free_tfms_skcipher(cc);
2295}
2296
2297static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
2298{
2299 unsigned int i;
2300 int err;
2301
2302 cc->cipher_tfm.tfms = kzalloc_objs(struct crypto_skcipher *,
2303 cc->tfms_count);
2304 if (!cc->cipher_tfm.tfms)
2305 return -ENOMEM;
2306
2307 for (i = 0; i < cc->tfms_count; i++) {
2308 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0,
2309 CRYPTO_ALG_ALLOCATES_MEMORY);
2310 if (IS_ERR(cc->cipher_tfm.tfms[i])) {
2311 err = PTR_ERR(cc->cipher_tfm.tfms[i]);
2312 crypt_free_tfms(cc);
2313 return err;
2314 }
2315 }
2316
2317 /*
2318 * dm-crypt performance can vary greatly depending on which crypto
2319 * algorithm implementation is used. Help people debug performance
2320 * problems by logging the ->cra_driver_name.
2321 */
2322 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2323 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
2324 return 0;
2325}
2326
2327static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
2328{
2329 int err;
2330
2331 cc->cipher_tfm.tfms = kmalloc_obj(struct crypto_skcipher *);
2332 if (!cc->cipher_tfm.tfms)
2333 return -ENOMEM;
2334
2335 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0,
2336 CRYPTO_ALG_ALLOCATES_MEMORY);
2337 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2338 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
2339 crypt_free_tfms(cc);
2340 return err;
2341 }
2342
2343 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2344 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
2345 return 0;
2346}
2347
2348static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
2349{
2350 if (crypt_integrity_aead(cc))
2351 return crypt_alloc_tfms_aead(cc, ciphermode);
2352 else
2353 return crypt_alloc_tfms_skcipher(cc, ciphermode);
2354}
2355
2356static unsigned int crypt_subkey_size(struct crypt_config *cc)
2357{
2358 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
2359}
2360
2361static unsigned int crypt_authenckey_size(struct crypt_config *cc)
2362{
2363 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
2364}
2365
2366/*
2367 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
2368 * the key must be for some reason in special format.
2369 * This funcion converts cc->key to this special format.
2370 */
2371static void crypt_copy_authenckey(char *p, const void *key,
2372 unsigned int enckeylen, unsigned int authkeylen)
2373{
2374 struct crypto_authenc_key_param *param;
2375 struct rtattr *rta;
2376
2377 rta = (struct rtattr *)p;
2378 param = RTA_DATA(rta);
2379 param->enckeylen = cpu_to_be32(enckeylen);
2380 rta->rta_len = RTA_LENGTH(sizeof(*param));
2381 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
2382 p += RTA_SPACE(sizeof(*param));
2383 memcpy(p, key + enckeylen, authkeylen);
2384 p += authkeylen;
2385 memcpy(p, key, enckeylen);
2386}
2387
2388static int crypt_setkey(struct crypt_config *cc)
2389{
2390 unsigned int subkey_size;
2391 int err = 0, i, r;
2392
2393 /* Ignore extra keys (which are used for IV etc) */
2394 subkey_size = crypt_subkey_size(cc);
2395
2396 if (crypt_integrity_hmac(cc)) {
2397 if (subkey_size < cc->key_mac_size)
2398 return -EINVAL;
2399
2400 crypt_copy_authenckey(cc->authenc_key, cc->key,
2401 subkey_size - cc->key_mac_size,
2402 cc->key_mac_size);
2403 }
2404
2405 for (i = 0; i < cc->tfms_count; i++) {
2406 if (crypt_integrity_hmac(cc))
2407 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2408 cc->authenc_key, crypt_authenckey_size(cc));
2409 else if (crypt_integrity_aead(cc))
2410 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2411 cc->key + (i * subkey_size),
2412 subkey_size);
2413 else
2414 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
2415 cc->key + (i * subkey_size),
2416 subkey_size);
2417 if (r)
2418 err = r;
2419 }
2420
2421 if (crypt_integrity_hmac(cc))
2422 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
2423
2424 return err;
2425}
2426
2427#ifdef CONFIG_KEYS
2428
2429static bool contains_whitespace(const char *str)
2430{
2431 while (*str)
2432 if (isspace(*str++))
2433 return true;
2434 return false;
2435}
2436
2437static int set_key_user(struct crypt_config *cc, struct key *key)
2438{
2439 const struct user_key_payload *ukp;
2440
2441 ukp = user_key_payload_locked(key);
2442 if (!ukp)
2443 return -EKEYREVOKED;
2444
2445 if (cc->key_size != ukp->datalen)
2446 return -EINVAL;
2447
2448 memcpy(cc->key, ukp->data, cc->key_size);
2449
2450 return 0;
2451}
2452
2453static int set_key_encrypted(struct crypt_config *cc, struct key *key)
2454{
2455 const struct encrypted_key_payload *ekp;
2456
2457 ekp = key->payload.data[0];
2458 if (!ekp)
2459 return -EKEYREVOKED;
2460
2461 if (cc->key_size != ekp->decrypted_datalen)
2462 return -EINVAL;
2463
2464 memcpy(cc->key, ekp->decrypted_data, cc->key_size);
2465
2466 return 0;
2467}
2468
2469static int set_key_trusted(struct crypt_config *cc, struct key *key)
2470{
2471 const struct trusted_key_payload *tkp;
2472
2473 tkp = key->payload.data[0];
2474 if (!tkp)
2475 return -EKEYREVOKED;
2476
2477 if (cc->key_size != tkp->key_len)
2478 return -EINVAL;
2479
2480 memcpy(cc->key, tkp->key, cc->key_size);
2481
2482 return 0;
2483}
2484
2485static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2486{
2487 char *new_key_string, *key_desc;
2488 int ret;
2489 struct key_type *type;
2490 struct key *key;
2491 int (*set_key)(struct crypt_config *cc, struct key *key);
2492
2493 /*
2494 * Reject key_string with whitespace. dm core currently lacks code for
2495 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2496 */
2497 if (contains_whitespace(key_string)) {
2498 DMERR("whitespace chars not allowed in key string");
2499 return -EINVAL;
2500 }
2501
2502 /* look for next ':' separating key_type from key_description */
2503 key_desc = strchr(key_string, ':');
2504 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2505 return -EINVAL;
2506
2507 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
2508 type = &key_type_logon;
2509 set_key = set_key_user;
2510 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
2511 type = &key_type_user;
2512 set_key = set_key_user;
2513 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) &&
2514 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
2515 type = &key_type_encrypted;
2516 set_key = set_key_encrypted;
2517 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) &&
2518 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) {
2519 type = &key_type_trusted;
2520 set_key = set_key_trusted;
2521 } else {
2522 return -EINVAL;
2523 }
2524
2525 new_key_string = kstrdup(key_string, GFP_KERNEL);
2526 if (!new_key_string)
2527 return -ENOMEM;
2528
2529 key = request_key(type, key_desc + 1, NULL);
2530 if (IS_ERR(key)) {
2531 ret = PTR_ERR(key);
2532 goto free_new_key_string;
2533 }
2534
2535 down_read(&key->sem);
2536 ret = set_key(cc, key);
2537 up_read(&key->sem);
2538 key_put(key);
2539 if (ret < 0)
2540 goto free_new_key_string;
2541
2542 /* clear the flag since following operations may invalidate previously valid key */
2543 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2544
2545 ret = crypt_setkey(cc);
2546 if (ret)
2547 goto free_new_key_string;
2548
2549 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2550 kfree_sensitive(cc->key_string);
2551 cc->key_string = new_key_string;
2552 return 0;
2553
2554free_new_key_string:
2555 kfree_sensitive(new_key_string);
2556 return ret;
2557}
2558
2559static int get_key_size(char **key_string)
2560{
2561 char *colon, dummy;
2562 int ret;
2563
2564 if (*key_string[0] != ':')
2565 return strlen(*key_string) >> 1;
2566
2567 /* look for next ':' in key string */
2568 colon = strpbrk(*key_string + 1, ":");
2569 if (!colon)
2570 return -EINVAL;
2571
2572 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2573 return -EINVAL;
2574
2575 *key_string = colon;
2576
2577 /* remaining key string should be :<logon|user>:<key_desc> */
2578
2579 return ret;
2580}
2581
2582#else
2583
2584static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2585{
2586 return -EINVAL;
2587}
2588
2589static int get_key_size(char **key_string)
2590{
2591 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1);
2592}
2593
2594#endif /* CONFIG_KEYS */
2595
2596static int crypt_set_key(struct crypt_config *cc, char *key)
2597{
2598 int r = -EINVAL;
2599 int key_string_len = strlen(key);
2600
2601 /* Hyphen (which gives a key_size of zero) means there is no key. */
2602 if (!cc->key_size && strcmp(key, "-"))
2603 goto out;
2604
2605 /* ':' means the key is in kernel keyring, short-circuit normal key processing */
2606 if (key[0] == ':') {
2607 r = crypt_set_keyring_key(cc, key + 1);
2608 goto out;
2609 }
2610
2611 /* clear the flag since following operations may invalidate previously valid key */
2612 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2613
2614 /* wipe references to any kernel keyring key */
2615 kfree_sensitive(cc->key_string);
2616 cc->key_string = NULL;
2617
2618 /* Decode key from its hex representation. */
2619 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2620 goto out;
2621
2622 r = crypt_setkey(cc);
2623 if (!r)
2624 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2625
2626out:
2627 /* Hex key string not needed after here, so wipe it. */
2628 memset(key, '0', key_string_len);
2629
2630 return r;
2631}
2632
2633static int crypt_wipe_key(struct crypt_config *cc)
2634{
2635 int r;
2636
2637 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2638 get_random_bytes(&cc->key, cc->key_size);
2639
2640 /* Wipe IV private keys */
2641 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe)
2642 cc->iv_gen_ops->wipe(cc);
2643
2644 kfree_sensitive(cc->key_string);
2645 cc->key_string = NULL;
2646 r = crypt_setkey(cc);
2647 memset(&cc->key, 0, cc->key_size * sizeof(u8));
2648
2649 return r;
2650}
2651
2652static void crypt_calculate_pages_per_client(void)
2653{
2654 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
2655
2656 if (!dm_crypt_clients_n)
2657 return;
2658
2659 pages /= dm_crypt_clients_n;
2660 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
2661 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
2662 dm_crypt_pages_per_client = pages;
2663}
2664
2665static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
2666{
2667 struct crypt_config *cc = pool_data;
2668 struct page *page;
2669
2670 /*
2671 * Note, percpu_counter_read_positive() may over (and under) estimate
2672 * the current usage by at most (batch - 1) * num_online_cpus() pages,
2673 * but avoids potential spinlock contention of an exact result.
2674 */
2675 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) &&
2676 likely(gfp_mask & __GFP_NORETRY))
2677 return NULL;
2678
2679 page = alloc_page(gfp_mask);
2680 if (likely(page != NULL))
2681 percpu_counter_add(&cc->n_allocated_pages, 1);
2682
2683 return page;
2684}
2685
2686static void crypt_page_free(void *page, void *pool_data)
2687{
2688 struct crypt_config *cc = pool_data;
2689
2690 __free_page(page);
2691 percpu_counter_sub(&cc->n_allocated_pages, 1);
2692}
2693
2694static void crypt_dtr(struct dm_target *ti)
2695{
2696 struct crypt_config *cc = ti->private;
2697
2698 ti->private = NULL;
2699
2700 if (!cc)
2701 return;
2702
2703 if (cc->write_thread)
2704 kthread_stop(cc->write_thread);
2705
2706 if (cc->io_queue)
2707 destroy_workqueue(cc->io_queue);
2708 if (cc->crypt_queue)
2709 destroy_workqueue(cc->crypt_queue);
2710
2711 if (cc->workqueue_id)
2712 ida_free(&workqueue_ida, cc->workqueue_id);
2713
2714 crypt_free_tfms(cc);
2715
2716 bioset_exit(&cc->bs);
2717
2718 mempool_exit(&cc->page_pool);
2719 mempool_exit(&cc->req_pool);
2720 mempool_exit(&cc->tag_pool);
2721
2722 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
2723 percpu_counter_destroy(&cc->n_allocated_pages);
2724
2725 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2726 cc->iv_gen_ops->dtr(cc);
2727
2728 if (cc->dev)
2729 dm_put_device(ti, cc->dev);
2730
2731 kfree_sensitive(cc->cipher_string);
2732 kfree_sensitive(cc->key_string);
2733 kfree_sensitive(cc->cipher_auth);
2734 kfree_sensitive(cc->authenc_key);
2735
2736 mutex_destroy(&cc->bio_alloc_lock);
2737
2738 /* Must zero key material before freeing */
2739 kfree_sensitive(cc);
2740
2741 spin_lock(&dm_crypt_clients_lock);
2742 WARN_ON(!dm_crypt_clients_n);
2743 dm_crypt_clients_n--;
2744 crypt_calculate_pages_per_client();
2745 spin_unlock(&dm_crypt_clients_lock);
2746
2747 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1);
2748}
2749
2750static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2751{
2752 struct crypt_config *cc = ti->private;
2753
2754 if (crypt_integrity_aead(cc))
2755 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2756 else
2757 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2758
2759 if (cc->iv_size)
2760 /* at least a 64 bit sector number should fit in our buffer */
2761 cc->iv_size = max(cc->iv_size,
2762 (unsigned int)(sizeof(u64) / sizeof(u8)));
2763 else if (ivmode) {
2764 DMWARN("Selected cipher does not support IVs");
2765 ivmode = NULL;
2766 }
2767
2768 /* Choose ivmode, see comments at iv code. */
2769 if (ivmode == NULL)
2770 cc->iv_gen_ops = NULL;
2771 else if (strcmp(ivmode, "plain") == 0)
2772 cc->iv_gen_ops = &crypt_iv_plain_ops;
2773 else if (strcmp(ivmode, "plain64") == 0)
2774 cc->iv_gen_ops = &crypt_iv_plain64_ops;
2775 else if (strcmp(ivmode, "plain64be") == 0)
2776 cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2777 else if (strcmp(ivmode, "essiv") == 0)
2778 cc->iv_gen_ops = &crypt_iv_essiv_ops;
2779 else if (strcmp(ivmode, "benbi") == 0)
2780 cc->iv_gen_ops = &crypt_iv_benbi_ops;
2781 else if (strcmp(ivmode, "null") == 0)
2782 cc->iv_gen_ops = &crypt_iv_null_ops;
2783 else if (strcmp(ivmode, "eboiv") == 0)
2784 cc->iv_gen_ops = &crypt_iv_eboiv_ops;
2785 else if (strcmp(ivmode, "elephant") == 0) {
2786 cc->iv_gen_ops = &crypt_iv_elephant_ops;
2787 cc->key_parts = 2;
2788 cc->key_extra_size = cc->key_size / 2;
2789 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
2790 return -EINVAL;
2791 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
2792 } else if (strcmp(ivmode, "lmk") == 0) {
2793 cc->iv_gen_ops = &crypt_iv_lmk_ops;
2794 /*
2795 * Version 2 and 3 is recognised according
2796 * to length of provided multi-key string.
2797 * If present (version 3), last key is used as IV seed.
2798 * All keys (including IV seed) are always the same size.
2799 */
2800 if (cc->key_size % cc->key_parts) {
2801 cc->key_parts++;
2802 cc->key_extra_size = cc->key_size / cc->key_parts;
2803 }
2804 } else if (strcmp(ivmode, "tcw") == 0) {
2805 cc->iv_gen_ops = &crypt_iv_tcw_ops;
2806 cc->key_parts += 2; /* IV + whitening */
2807 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2808 } else if (strcmp(ivmode, "random") == 0) {
2809 cc->iv_gen_ops = &crypt_iv_random_ops;
2810 /* Need storage space in integrity fields. */
2811 cc->integrity_iv_size = cc->iv_size;
2812 } else {
2813 ti->error = "Invalid IV mode";
2814 return -EINVAL;
2815 }
2816
2817 return 0;
2818}
2819
2820/*
2821 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2822 * The HMAC is needed to calculate tag size (HMAC digest size).
2823 * This should be probably done by crypto-api calls (once available...)
2824 */
2825static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2826{
2827 char *start, *end, *mac_alg = NULL;
2828 struct crypto_ahash *mac;
2829
2830 if (!strstarts(cipher_api, "authenc("))
2831 return 0;
2832
2833 start = strchr(cipher_api, '(');
2834 end = strchr(cipher_api, ',');
2835 if (!start || !end || ++start > end)
2836 return -EINVAL;
2837
2838 mac_alg = kmemdup_nul(start, end - start, GFP_KERNEL);
2839 if (!mac_alg)
2840 return -ENOMEM;
2841
2842 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY);
2843 kfree(mac_alg);
2844
2845 if (IS_ERR(mac))
2846 return PTR_ERR(mac);
2847
2848 if (!test_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags))
2849 cc->key_mac_size = crypto_ahash_digestsize(mac);
2850 crypto_free_ahash(mac);
2851
2852 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2853 if (!cc->authenc_key)
2854 return -ENOMEM;
2855
2856 return 0;
2857}
2858
2859static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2860 char **ivmode, char **ivopts)
2861{
2862 struct crypt_config *cc = ti->private;
2863 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
2864 int ret = -EINVAL;
2865
2866 cc->tfms_count = 1;
2867
2868 /*
2869 * New format (capi: prefix)
2870 * capi:cipher_api_spec-iv:ivopts
2871 */
2872 tmp = &cipher_in[strlen("capi:")];
2873
2874 /* Separate IV options if present, it can contain another '-' in hash name */
2875 *ivopts = strrchr(tmp, ':');
2876 if (*ivopts) {
2877 **ivopts = '\0';
2878 (*ivopts)++;
2879 }
2880 /* Parse IV mode */
2881 *ivmode = strrchr(tmp, '-');
2882 if (*ivmode) {
2883 **ivmode = '\0';
2884 (*ivmode)++;
2885 }
2886 /* The rest is crypto API spec */
2887 cipher_api = tmp;
2888
2889 /* Alloc AEAD, can be used only in new format. */
2890 if (crypt_integrity_aead(cc)) {
2891 ret = crypt_ctr_auth_cipher(cc, cipher_api);
2892 if (ret < 0) {
2893 ti->error = "Invalid AEAD cipher spec";
2894 return ret;
2895 }
2896 }
2897
2898 if (*ivmode && !strcmp(*ivmode, "lmk"))
2899 cc->tfms_count = 64;
2900
2901 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2902 if (!*ivopts) {
2903 ti->error = "Digest algorithm missing for ESSIV mode";
2904 return -EINVAL;
2905 }
2906 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
2907 cipher_api, *ivopts);
2908 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2909 ti->error = "Cannot allocate cipher string";
2910 return -ENOMEM;
2911 }
2912 cipher_api = buf;
2913 }
2914
2915 cc->key_parts = cc->tfms_count;
2916
2917 /* Allocate cipher */
2918 ret = crypt_alloc_tfms(cc, cipher_api);
2919 if (ret < 0) {
2920 ti->error = "Error allocating crypto tfm";
2921 return ret;
2922 }
2923
2924 if (crypt_integrity_aead(cc))
2925 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2926 else
2927 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2928
2929 return 0;
2930}
2931
2932static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2933 char **ivmode, char **ivopts)
2934{
2935 struct crypt_config *cc = ti->private;
2936 char *tmp, *cipher, *chainmode, *keycount;
2937 char *cipher_api = NULL;
2938 int ret = -EINVAL;
2939 char dummy;
2940
2941 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2942 ti->error = "Bad cipher specification";
2943 return -EINVAL;
2944 }
2945
2946 /*
2947 * Legacy dm-crypt cipher specification
2948 * cipher[:keycount]-mode-iv:ivopts
2949 */
2950 tmp = cipher_in;
2951 keycount = strsep(&tmp, "-");
2952 cipher = strsep(&keycount, ":");
2953
2954 if (!keycount)
2955 cc->tfms_count = 1;
2956 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
2957 !is_power_of_2(cc->tfms_count)) {
2958 ti->error = "Bad cipher key count specification";
2959 return -EINVAL;
2960 }
2961 cc->key_parts = cc->tfms_count;
2962
2963 chainmode = strsep(&tmp, "-");
2964 *ivmode = strsep(&tmp, ":");
2965 *ivopts = tmp;
2966
2967 /*
2968 * For compatibility with the original dm-crypt mapping format, if
2969 * only the cipher name is supplied, use cbc-plain.
2970 */
2971 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
2972 chainmode = "cbc";
2973 *ivmode = "plain";
2974 }
2975
2976 if (strcmp(chainmode, "ecb") && !*ivmode) {
2977 ti->error = "IV mechanism required";
2978 return -EINVAL;
2979 }
2980
2981 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
2982 if (!cipher_api)
2983 goto bad_mem;
2984
2985 if (*ivmode && !strcmp(*ivmode, "essiv")) {
2986 if (!*ivopts) {
2987 ti->error = "Digest algorithm missing for ESSIV mode";
2988 kfree(cipher_api);
2989 return -EINVAL;
2990 }
2991 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2992 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
2993 } else {
2994 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2995 "%s(%s)", chainmode, cipher);
2996 }
2997 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2998 kfree(cipher_api);
2999 goto bad_mem;
3000 }
3001
3002 /* Allocate cipher */
3003 ret = crypt_alloc_tfms(cc, cipher_api);
3004 if (ret < 0) {
3005 ti->error = "Error allocating crypto tfm";
3006 kfree(cipher_api);
3007 return ret;
3008 }
3009 kfree(cipher_api);
3010
3011 return 0;
3012bad_mem:
3013 ti->error = "Cannot allocate cipher strings";
3014 return -ENOMEM;
3015}
3016
3017static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
3018{
3019 struct crypt_config *cc = ti->private;
3020 char *ivmode = NULL, *ivopts = NULL;
3021 int ret;
3022
3023 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
3024 if (!cc->cipher_string) {
3025 ti->error = "Cannot allocate cipher strings";
3026 return -ENOMEM;
3027 }
3028
3029 if (strstarts(cipher_in, "capi:"))
3030 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
3031 else
3032 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
3033 if (ret)
3034 return ret;
3035
3036 /* Initialize IV */
3037 ret = crypt_ctr_ivmode(ti, ivmode);
3038 if (ret < 0)
3039 return ret;
3040
3041 /* Initialize and set key */
3042 ret = crypt_set_key(cc, key);
3043 if (ret < 0) {
3044 ti->error = "Error decoding and setting key";
3045 return ret;
3046 }
3047
3048 /* Allocate IV */
3049 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
3050 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
3051 if (ret < 0) {
3052 ti->error = "Error creating IV";
3053 return ret;
3054 }
3055 }
3056
3057 /* Initialize IV (set keys for ESSIV etc) */
3058 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
3059 ret = cc->iv_gen_ops->init(cc);
3060 if (ret < 0) {
3061 ti->error = "Error initialising IV";
3062 return ret;
3063 }
3064 }
3065
3066 /* wipe the kernel key payload copy */
3067 if (cc->key_string)
3068 memset(cc->key, 0, cc->key_size * sizeof(u8));
3069
3070 return ret;
3071}
3072
3073static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
3074{
3075 struct crypt_config *cc = ti->private;
3076 struct dm_arg_set as;
3077 static const struct dm_arg _args[] = {
3078 {0, 9, "Invalid number of feature args"},
3079 };
3080 unsigned int opt_params, val;
3081 const char *opt_string, *sval;
3082 char dummy;
3083 int ret;
3084
3085 /* Optional parameters */
3086 as.argc = argc;
3087 as.argv = argv;
3088
3089 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
3090 if (ret)
3091 return ret;
3092
3093 while (opt_params--) {
3094 opt_string = dm_shift_arg(&as);
3095 if (!opt_string) {
3096 ti->error = "Not enough feature arguments";
3097 return -EINVAL;
3098 }
3099
3100 if (!strcasecmp(opt_string, "allow_discards"))
3101 ti->num_discard_bios = 1;
3102
3103 else if (!strcasecmp(opt_string, "same_cpu_crypt"))
3104 set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3105 else if (!strcasecmp(opt_string, "high_priority"))
3106 set_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags);
3107
3108 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
3109 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3110 else if (!strcasecmp(opt_string, "no_read_workqueue"))
3111 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3112 else if (!strcasecmp(opt_string, "no_write_workqueue"))
3113 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3114 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
3115 if (val == 0 || val > MAX_TAG_SIZE) {
3116 ti->error = "Invalid integrity arguments";
3117 return -EINVAL;
3118 }
3119 cc->used_tag_size = val;
3120 sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
3121 if (!strcasecmp(sval, "aead")) {
3122 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
3123 } else if (strcasecmp(sval, "none")) {
3124 ti->error = "Unknown integrity profile";
3125 return -EINVAL;
3126 }
3127
3128 cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
3129 if (!cc->cipher_auth)
3130 return -ENOMEM;
3131 } else if (sscanf(opt_string, "integrity_key_size:%u%c", &val, &dummy) == 1) {
3132 if (!val) {
3133 ti->error = "Invalid integrity_key_size argument";
3134 return -EINVAL;
3135 }
3136 cc->key_mac_size = val;
3137 set_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags);
3138 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
3139 if (cc->sector_size < (1 << SECTOR_SHIFT) ||
3140 cc->sector_size > 4096 ||
3141 (cc->sector_size & (cc->sector_size - 1))) {
3142 ti->error = "Invalid feature value for sector_size";
3143 return -EINVAL;
3144 }
3145 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
3146 ti->error = "Device size is not multiple of sector_size feature";
3147 return -EINVAL;
3148 }
3149 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
3150 } else if (!strcasecmp(opt_string, "iv_large_sectors"))
3151 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3152 else {
3153 ti->error = "Invalid feature arguments";
3154 return -EINVAL;
3155 }
3156 }
3157
3158 return 0;
3159}
3160
3161#ifdef CONFIG_BLK_DEV_ZONED
3162static int crypt_report_zones(struct dm_target *ti,
3163 struct dm_report_zones_args *args, unsigned int nr_zones)
3164{
3165 struct crypt_config *cc = ti->private;
3166
3167 return dm_report_zones(cc->dev->bdev, cc->start,
3168 cc->start + dm_target_offset(ti, args->next_sector),
3169 args, nr_zones);
3170}
3171#else
3172#define crypt_report_zones NULL
3173#endif
3174
3175/*
3176 * Construct an encryption mapping:
3177 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
3178 */
3179static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3180{
3181 struct crypt_config *cc;
3182 const char *devname = dm_table_device_name(ti->table);
3183 int key_size, wq_id;
3184 unsigned int align_mask;
3185 unsigned int common_wq_flags;
3186 unsigned long long tmpll;
3187 int ret;
3188 size_t iv_size_padding, additional_req_size;
3189 char dummy;
3190
3191 if (argc < 5) {
3192 ti->error = "Not enough arguments";
3193 return -EINVAL;
3194 }
3195
3196 key_size = get_key_size(&argv[1]);
3197 if (key_size < 0) {
3198 ti->error = "Cannot parse key size";
3199 return -EINVAL;
3200 }
3201
3202 cc = kzalloc_flex(*cc, key, key_size);
3203 if (!cc) {
3204 ti->error = "Cannot allocate encryption context";
3205 return -ENOMEM;
3206 }
3207 cc->key_size = key_size;
3208 cc->sector_size = (1 << SECTOR_SHIFT);
3209 cc->sector_shift = 0;
3210
3211 ti->private = cc;
3212
3213 spin_lock(&dm_crypt_clients_lock);
3214 dm_crypt_clients_n++;
3215 crypt_calculate_pages_per_client();
3216 spin_unlock(&dm_crypt_clients_lock);
3217
3218 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
3219 if (ret < 0)
3220 goto bad;
3221
3222 /* Optional parameters need to be read before cipher constructor */
3223 if (argc > 5) {
3224 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
3225 if (ret)
3226 goto bad;
3227 }
3228
3229 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
3230 if (ret < 0)
3231 goto bad;
3232
3233 if (crypt_integrity_aead(cc)) {
3234 cc->dmreq_start = sizeof(struct aead_request);
3235 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
3236 align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
3237 } else {
3238 cc->dmreq_start = sizeof(struct skcipher_request);
3239 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
3240 align_mask = crypto_skcipher_alignmask(any_tfm(cc));
3241 }
3242 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
3243
3244 if (align_mask < CRYPTO_MINALIGN) {
3245 /* Allocate the padding exactly */
3246 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
3247 & align_mask;
3248 } else {
3249 /*
3250 * If the cipher requires greater alignment than kmalloc
3251 * alignment, we don't know the exact position of the
3252 * initialization vector. We must assume worst case.
3253 */
3254 iv_size_padding = align_mask;
3255 }
3256
3257 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */
3258 additional_req_size = sizeof(struct dm_crypt_request) +
3259 iv_size_padding + cc->iv_size +
3260 cc->iv_size +
3261 sizeof(uint64_t) +
3262 sizeof(unsigned int);
3263
3264 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
3265 if (ret) {
3266 ti->error = "Cannot allocate crypt request mempool";
3267 goto bad;
3268 }
3269
3270 cc->per_bio_data_size = ti->per_io_data_size =
3271 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
3272 ARCH_DMA_MINALIGN);
3273
3274 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc);
3275 if (ret) {
3276 ti->error = "Cannot allocate page mempool";
3277 goto bad;
3278 }
3279
3280 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
3281 if (ret) {
3282 ti->error = "Cannot allocate crypt bioset";
3283 goto bad;
3284 }
3285
3286 mutex_init(&cc->bio_alloc_lock);
3287
3288 ret = -EINVAL;
3289 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
3290 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
3291 ti->error = "Invalid iv_offset sector";
3292 goto bad;
3293 }
3294 cc->iv_offset = tmpll;
3295
3296 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
3297 if (ret) {
3298 ti->error = "Device lookup failed";
3299 goto bad;
3300 }
3301
3302 ret = -EINVAL;
3303 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
3304 ti->error = "Invalid device sector";
3305 goto bad;
3306 }
3307 cc->start = tmpll;
3308
3309 if (bdev_is_zoned(cc->dev->bdev)) {
3310 /*
3311 * For zoned block devices, we need to preserve the issuer write
3312 * ordering. To do so, disable write workqueues and force inline
3313 * encryption completion.
3314 */
3315 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3316 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
3317
3318 /*
3319 * All zone append writes to a zone of a zoned block device will
3320 * have the same BIO sector, the start of the zone. When the
3321 * cypher IV mode uses sector values, all data targeting a
3322 * zone will be encrypted using the first sector numbers of the
3323 * zone. This will not result in write errors but will
3324 * cause most reads to fail as reads will use the sector values
3325 * for the actual data locations, resulting in IV mismatch.
3326 * To avoid this problem, ask DM core to emulate zone append
3327 * operations with regular writes.
3328 */
3329 DMDEBUG("Zone append operations will be emulated");
3330 ti->emulate_zone_append = true;
3331 }
3332
3333 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
3334 ret = crypt_integrity_ctr(cc, ti);
3335 if (ret)
3336 goto bad;
3337
3338 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->tuple_size;
3339 if (!cc->tag_pool_max_sectors)
3340 cc->tag_pool_max_sectors = 1;
3341
3342 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
3343 cc->tag_pool_max_sectors * cc->tuple_size);
3344 if (ret) {
3345 ti->error = "Cannot allocate integrity tags mempool";
3346 goto bad;
3347 }
3348
3349 cc->tag_pool_max_sectors <<= cc->sector_shift;
3350 }
3351
3352 wq_id = ida_alloc_min(&workqueue_ida, 1, GFP_KERNEL);
3353 if (wq_id < 0) {
3354 ti->error = "Couldn't get workqueue id";
3355 ret = wq_id;
3356 goto bad;
3357 }
3358 cc->workqueue_id = wq_id;
3359
3360 ret = -ENOMEM;
3361 common_wq_flags = WQ_MEM_RECLAIM | WQ_SYSFS;
3362 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags))
3363 common_wq_flags |= WQ_HIGHPRI;
3364
3365 cc->io_queue = alloc_workqueue("kcryptd_io-%s-%d",
3366 common_wq_flags | WQ_PERCPU, 1,
3367 devname, wq_id);
3368 if (!cc->io_queue) {
3369 ti->error = "Couldn't create kcryptd io queue";
3370 goto bad;
3371 }
3372
3373 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) {
3374 cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d",
3375 common_wq_flags | WQ_CPU_INTENSIVE | WQ_PERCPU,
3376 1, devname, wq_id);
3377 } else {
3378 /*
3379 * While crypt_queue is certainly CPU intensive, the use of
3380 * WQ_CPU_INTENSIVE is meaningless with WQ_UNBOUND.
3381 */
3382 cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d",
3383 common_wq_flags | WQ_UNBOUND,
3384 num_online_cpus(), devname, wq_id);
3385 }
3386 if (!cc->crypt_queue) {
3387 ti->error = "Couldn't create kcryptd queue";
3388 goto bad;
3389 }
3390
3391 spin_lock_init(&cc->write_thread_lock);
3392 cc->write_tree = RB_ROOT;
3393
3394 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
3395 if (IS_ERR(cc->write_thread)) {
3396 ret = PTR_ERR(cc->write_thread);
3397 cc->write_thread = NULL;
3398 ti->error = "Couldn't spawn write thread";
3399 goto bad;
3400 }
3401 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags))
3402 set_user_nice(cc->write_thread, MIN_NICE);
3403
3404 ti->num_flush_bios = 1;
3405 ti->limit_swap_bios = true;
3406 ti->accounts_remapped_io = true;
3407
3408 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1);
3409 return 0;
3410
3411bad:
3412 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0);
3413 crypt_dtr(ti);
3414 return ret;
3415}
3416
3417static int crypt_map(struct dm_target *ti, struct bio *bio)
3418{
3419 struct dm_crypt_io *io;
3420 struct crypt_config *cc = ti->private;
3421 unsigned max_sectors;
3422 bool no_split;
3423
3424 /*
3425 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
3426 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
3427 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
3428 */
3429 if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
3430 bio_op(bio) == REQ_OP_DISCARD)) {
3431 bio_set_dev(bio, cc->dev->bdev);
3432 if (bio_sectors(bio))
3433 bio->bi_iter.bi_sector = cc->start +
3434 dm_target_offset(ti, bio->bi_iter.bi_sector);
3435 return DM_MAPIO_REMAPPED;
3436 }
3437
3438 /*
3439 * Check if bio is too large, split as needed.
3440 *
3441 * For zoned devices, splitting write operations creates the
3442 * risk of deadlocking queue freeze operations with zone write
3443 * plugging BIO work when the reminder of a split BIO is
3444 * issued. So always allow the entire BIO to proceed.
3445 */
3446 no_split = (ti->emulate_zone_append && op_is_write(bio_op(bio))) ||
3447 (bio->bi_opf & REQ_ATOMIC);
3448 max_sectors = get_max_request_sectors(ti, bio, no_split);
3449 if (unlikely(bio_sectors(bio) > max_sectors)) {
3450 if (unlikely(no_split))
3451 return DM_MAPIO_KILL;
3452 dm_accept_partial_bio(bio, max_sectors);
3453 }
3454
3455 /*
3456 * Ensure that bio is a multiple of internal sector encryption size
3457 * and is aligned to this size as defined in IO hints.
3458 */
3459 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
3460 return DM_MAPIO_KILL;
3461
3462 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
3463 return DM_MAPIO_KILL;
3464
3465 io = dm_per_bio_data(bio, cc->per_bio_data_size);
3466 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
3467
3468 if (cc->tuple_size) {
3469 unsigned int tag_len = cc->tuple_size * (bio_sectors(bio) >> cc->sector_shift);
3470
3471 if (unlikely(tag_len > KMALLOC_MAX_SIZE))
3472 io->integrity_metadata = NULL;
3473 else
3474 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
3475
3476 if (unlikely(!io->integrity_metadata)) {
3477 if (bio_sectors(bio) > cc->tag_pool_max_sectors)
3478 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
3479 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
3480 io->integrity_metadata_from_pool = true;
3481 }
3482 }
3483
3484 if (crypt_integrity_aead(cc))
3485 io->ctx.r.req_aead = (struct aead_request *)(io + 1);
3486 else
3487 io->ctx.r.req = (struct skcipher_request *)(io + 1);
3488
3489 if (bio_data_dir(io->base_bio) == READ) {
3490 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP))
3491 kcryptd_queue_read(io);
3492 } else
3493 kcryptd_queue_crypt(io);
3494
3495 return DM_MAPIO_SUBMITTED;
3496}
3497
3498static char hex2asc(unsigned char c)
3499{
3500 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27);
3501}
3502
3503static void crypt_status(struct dm_target *ti, status_type_t type,
3504 unsigned int status_flags, char *result, unsigned int maxlen)
3505{
3506 struct crypt_config *cc = ti->private;
3507 unsigned int i, sz = 0;
3508 int num_feature_args = 0;
3509
3510 switch (type) {
3511 case STATUSTYPE_INFO:
3512 result[0] = '\0';
3513 break;
3514
3515 case STATUSTYPE_TABLE:
3516 DMEMIT("%s ", cc->cipher_string);
3517
3518 if (cc->key_size > 0) {
3519 if (cc->key_string)
3520 DMEMIT(":%u:%s", cc->key_size, cc->key_string);
3521 else {
3522 for (i = 0; i < cc->key_size; i++) {
3523 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4),
3524 hex2asc(cc->key[i] & 0xf));
3525 }
3526 }
3527 } else
3528 DMEMIT("-");
3529
3530 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
3531 cc->dev->name, (unsigned long long)cc->start);
3532
3533 num_feature_args += !!ti->num_discard_bios;
3534 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3535 num_feature_args += test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags);
3536 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3537 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3538 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3539 num_feature_args += !!cc->used_tag_size;
3540 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
3541 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3542 num_feature_args += test_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags);
3543 if (num_feature_args) {
3544 DMEMIT(" %d", num_feature_args);
3545 if (ti->num_discard_bios)
3546 DMEMIT(" allow_discards");
3547 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3548 DMEMIT(" same_cpu_crypt");
3549 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags))
3550 DMEMIT(" high_priority");
3551 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
3552 DMEMIT(" submit_from_crypt_cpus");
3553 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
3554 DMEMIT(" no_read_workqueue");
3555 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
3556 DMEMIT(" no_write_workqueue");
3557 if (cc->used_tag_size)
3558 DMEMIT(" integrity:%u:%s", cc->used_tag_size, cc->cipher_auth);
3559 if (cc->sector_size != (1 << SECTOR_SHIFT))
3560 DMEMIT(" sector_size:%d", cc->sector_size);
3561 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
3562 DMEMIT(" iv_large_sectors");
3563 if (test_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags))
3564 DMEMIT(" integrity_key_size:%u", cc->key_mac_size);
3565 }
3566 break;
3567
3568 case STATUSTYPE_IMA:
3569 DMEMIT_TARGET_NAME_VERSION(ti->type);
3570 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n');
3571 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n');
3572 DMEMIT(",high_priority=%c", test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags) ? 'y' : 'n');
3573 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ?
3574 'y' : 'n');
3575 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ?
3576 'y' : 'n');
3577 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ?
3578 'y' : 'n');
3579 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ?
3580 'y' : 'n');
3581
3582 if (cc->used_tag_size)
3583 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s",
3584 cc->used_tag_size, cc->cipher_auth);
3585 if (cc->sector_size != (1 << SECTOR_SHIFT))
3586 DMEMIT(",sector_size=%d", cc->sector_size);
3587 if (cc->cipher_string)
3588 DMEMIT(",cipher_string=%s", cc->cipher_string);
3589
3590 DMEMIT(",key_size=%u", cc->key_size);
3591 DMEMIT(",key_parts=%u", cc->key_parts);
3592 DMEMIT(",key_extra_size=%u", cc->key_extra_size);
3593 DMEMIT(",key_mac_size=%u", cc->key_mac_size);
3594 DMEMIT(";");
3595 break;
3596 }
3597}
3598
3599static void crypt_postsuspend(struct dm_target *ti)
3600{
3601 struct crypt_config *cc = ti->private;
3602
3603 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3604}
3605
3606static int crypt_preresume(struct dm_target *ti)
3607{
3608 struct crypt_config *cc = ti->private;
3609
3610 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
3611 DMERR("aborting resume - crypt key is not set.");
3612 return -EAGAIN;
3613 }
3614
3615 return 0;
3616}
3617
3618static void crypt_resume(struct dm_target *ti)
3619{
3620 struct crypt_config *cc = ti->private;
3621
3622 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3623}
3624
3625/* Message interface
3626 * key set <key>
3627 * key wipe
3628 */
3629static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv,
3630 char *result, unsigned int maxlen)
3631{
3632 struct crypt_config *cc = ti->private;
3633 int key_size, ret = -EINVAL;
3634
3635 if (argc < 2)
3636 goto error;
3637
3638 if (!strcasecmp(argv[0], "key")) {
3639 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
3640 DMWARN("not suspended during key manipulation.");
3641 return -EINVAL;
3642 }
3643 if (argc == 3 && !strcasecmp(argv[1], "set")) {
3644 /* The key size may not be changed. */
3645 key_size = get_key_size(&argv[2]);
3646 if (key_size < 0 || cc->key_size != key_size) {
3647 memset(argv[2], '0', strlen(argv[2]));
3648 return -EINVAL;
3649 }
3650
3651 ret = crypt_set_key(cc, argv[2]);
3652 if (ret)
3653 return ret;
3654 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
3655 ret = cc->iv_gen_ops->init(cc);
3656 /* wipe the kernel key payload copy */
3657 if (cc->key_string)
3658 memset(cc->key, 0, cc->key_size * sizeof(u8));
3659 return ret;
3660 }
3661 if (argc == 2 && !strcasecmp(argv[1], "wipe"))
3662 return crypt_wipe_key(cc);
3663 }
3664
3665error:
3666 DMWARN("unrecognised message received.");
3667 return -EINVAL;
3668}
3669
3670static int crypt_iterate_devices(struct dm_target *ti,
3671 iterate_devices_callout_fn fn, void *data)
3672{
3673 struct crypt_config *cc = ti->private;
3674
3675 return fn(ti, cc->dev, cc->start, ti->len, data);
3676}
3677
3678static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
3679{
3680 struct crypt_config *cc = ti->private;
3681
3682 dm_stack_bs_limits(limits, cc->sector_size);
3683 limits->dma_alignment = limits->logical_block_size - 1;
3684
3685 /*
3686 * For zoned dm-crypt targets, there will be no internal splitting of
3687 * write BIOs to avoid exceeding BIO_MAX_VECS vectors per BIO. But
3688 * without respecting this limit, crypt_alloc_buffer() will trigger a
3689 * BUG(). Avoid this by forcing DM core to split write BIOs to this
3690 * limit.
3691 */
3692 if (ti->emulate_zone_append)
3693 limits->max_hw_sectors = min(limits->max_hw_sectors,
3694 BIO_MAX_VECS << PAGE_SECTORS_SHIFT);
3695
3696 limits->atomic_write_hw_unit_max = min(limits->atomic_write_hw_unit_max,
3697 BIO_MAX_VECS << PAGE_SHIFT);
3698 limits->atomic_write_hw_max = min(limits->atomic_write_hw_max,
3699 BIO_MAX_VECS << PAGE_SHIFT);
3700}
3701
3702static struct target_type crypt_target = {
3703 .name = "crypt",
3704 .version = {1, 29, 0},
3705 .module = THIS_MODULE,
3706 .ctr = crypt_ctr,
3707 .dtr = crypt_dtr,
3708 .features = DM_TARGET_ZONED_HM | DM_TARGET_ATOMIC_WRITES,
3709 .report_zones = crypt_report_zones,
3710 .map = crypt_map,
3711 .status = crypt_status,
3712 .postsuspend = crypt_postsuspend,
3713 .preresume = crypt_preresume,
3714 .resume = crypt_resume,
3715 .message = crypt_message,
3716 .iterate_devices = crypt_iterate_devices,
3717 .io_hints = crypt_io_hints,
3718};
3719module_dm(crypt);
3720
3721MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3722MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3723MODULE_LICENSE("GPL");