Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
bf14299f | 2 | * Copyright (C) 2003 Jana Saout <jana@saout.de> |
1da177e4 | 3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> |
54cea3f6 | 4 | * Copyright (C) 2006-2015 Red Hat, Inc. All rights reserved. |
ed04d981 | 5 | * Copyright (C) 2013 Milan Broz <gmazyland@gmail.com> |
1da177e4 LT |
6 | * |
7 | * This file is released under the GPL. | |
8 | */ | |
9 | ||
43d69034 | 10 | #include <linux/completion.h> |
d1806f6a | 11 | #include <linux/err.h> |
1da177e4 LT |
12 | #include <linux/module.h> |
13 | #include <linux/init.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/bio.h> | |
16 | #include <linux/blkdev.h> | |
17 | #include <linux/mempool.h> | |
18 | #include <linux/slab.h> | |
19 | #include <linux/crypto.h> | |
20 | #include <linux/workqueue.h> | |
dc267621 | 21 | #include <linux/kthread.h> |
3fcfab16 | 22 | #include <linux/backing-dev.h> |
60063497 | 23 | #include <linux/atomic.h> |
378f058c | 24 | #include <linux/scatterlist.h> |
b3c5fd30 | 25 | #include <linux/rbtree.h> |
1da177e4 | 26 | #include <asm/page.h> |
48527fa7 | 27 | #include <asm/unaligned.h> |
34745785 MB |
28 | #include <crypto/hash.h> |
29 | #include <crypto/md5.h> | |
30 | #include <crypto/algapi.h> | |
1da177e4 | 31 | |
586e80e6 | 32 | #include <linux/device-mapper.h> |
1da177e4 | 33 | |
72d94861 | 34 | #define DM_MSG_PREFIX "crypt" |
1da177e4 | 35 | |
1da177e4 LT |
36 | /* |
37 | * context holding the current state of a multi-part conversion | |
38 | */ | |
39 | struct convert_context { | |
43d69034 | 40 | struct completion restart; |
1da177e4 LT |
41 | struct bio *bio_in; |
42 | struct bio *bio_out; | |
003b5c57 KO |
43 | struct bvec_iter iter_in; |
44 | struct bvec_iter iter_out; | |
c66029f4 | 45 | sector_t cc_sector; |
40b6229b | 46 | atomic_t cc_pending; |
610f2de3 | 47 | struct ablkcipher_request *req; |
1da177e4 LT |
48 | }; |
49 | ||
53017030 MB |
50 | /* |
51 | * per bio private data | |
52 | */ | |
53 | struct dm_crypt_io { | |
49a8a920 | 54 | struct crypt_config *cc; |
53017030 MB |
55 | struct bio *base_bio; |
56 | struct work_struct work; | |
57 | ||
58 | struct convert_context ctx; | |
59 | ||
40b6229b | 60 | atomic_t io_pending; |
53017030 | 61 | int error; |
0c395b0f | 62 | sector_t sector; |
dc267621 | 63 | |
b3c5fd30 | 64 | struct rb_node rb_node; |
298a9fa0 | 65 | } CRYPTO_MINALIGN_ATTR; |
53017030 | 66 | |
01482b76 | 67 | struct dm_crypt_request { |
b2174eeb | 68 | struct convert_context *ctx; |
01482b76 MB |
69 | struct scatterlist sg_in; |
70 | struct scatterlist sg_out; | |
2dc5327d | 71 | sector_t iv_sector; |
01482b76 MB |
72 | }; |
73 | ||
1da177e4 LT |
74 | struct crypt_config; |
75 | ||
76 | struct crypt_iv_operations { | |
77 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 78 | const char *opts); |
1da177e4 | 79 | void (*dtr)(struct crypt_config *cc); |
b95bf2d3 | 80 | int (*init)(struct crypt_config *cc); |
542da317 | 81 | int (*wipe)(struct crypt_config *cc); |
2dc5327d MB |
82 | int (*generator)(struct crypt_config *cc, u8 *iv, |
83 | struct dm_crypt_request *dmreq); | |
84 | int (*post)(struct crypt_config *cc, u8 *iv, | |
85 | struct dm_crypt_request *dmreq); | |
1da177e4 LT |
86 | }; |
87 | ||
60473592 | 88 | struct iv_essiv_private { |
b95bf2d3 MB |
89 | struct crypto_hash *hash_tfm; |
90 | u8 *salt; | |
60473592 MB |
91 | }; |
92 | ||
93 | struct iv_benbi_private { | |
94 | int shift; | |
95 | }; | |
96 | ||
34745785 MB |
97 | #define LMK_SEED_SIZE 64 /* hash + 0 */ |
98 | struct iv_lmk_private { | |
99 | struct crypto_shash *hash_tfm; | |
100 | u8 *seed; | |
101 | }; | |
102 | ||
ed04d981 MB |
103 | #define TCW_WHITENING_SIZE 16 |
104 | struct iv_tcw_private { | |
105 | struct crypto_shash *crc32_tfm; | |
106 | u8 *iv_seed; | |
107 | u8 *whitening; | |
108 | }; | |
109 | ||
1da177e4 LT |
110 | /* |
111 | * Crypt: maps a linear range of a block device | |
112 | * and encrypts / decrypts at the same time. | |
113 | */ | |
0f5d8e6e | 114 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, |
bcbd94ff MP |
115 | DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, |
116 | DM_CRYPT_EXIT_THREAD}; | |
c0297721 AK |
117 | |
118 | /* | |
610f2de3 | 119 | * The fields in here must be read only after initialization. |
c0297721 | 120 | */ |
1da177e4 LT |
121 | struct crypt_config { |
122 | struct dm_dev *dev; | |
123 | sector_t start; | |
124 | ||
125 | /* | |
ddd42edf MB |
126 | * pool for per bio private data, crypto requests and |
127 | * encryption requeusts/buffer pages | |
1da177e4 | 128 | */ |
ddd42edf | 129 | mempool_t *req_pool; |
1da177e4 | 130 | mempool_t *page_pool; |
6a24c718 | 131 | struct bio_set *bs; |
7145c241 | 132 | struct mutex bio_alloc_lock; |
1da177e4 | 133 | |
cabf08e4 MB |
134 | struct workqueue_struct *io_queue; |
135 | struct workqueue_struct *crypt_queue; | |
3f1e9070 | 136 | |
dc267621 MP |
137 | struct task_struct *write_thread; |
138 | wait_queue_head_t write_thread_wait; | |
b3c5fd30 | 139 | struct rb_root write_tree; |
dc267621 | 140 | |
5ebaee6d | 141 | char *cipher; |
7dbcd137 | 142 | char *cipher_string; |
5ebaee6d | 143 | |
1da177e4 | 144 | struct crypt_iv_operations *iv_gen_ops; |
79066ad3 | 145 | union { |
60473592 MB |
146 | struct iv_essiv_private essiv; |
147 | struct iv_benbi_private benbi; | |
34745785 | 148 | struct iv_lmk_private lmk; |
ed04d981 | 149 | struct iv_tcw_private tcw; |
79066ad3 | 150 | } iv_gen_private; |
1da177e4 LT |
151 | sector_t iv_offset; |
152 | unsigned int iv_size; | |
153 | ||
fd2d231f MP |
154 | /* ESSIV: struct crypto_cipher *essiv_tfm */ |
155 | void *iv_private; | |
156 | struct crypto_ablkcipher **tfms; | |
d1f96423 | 157 | unsigned tfms_count; |
c0297721 | 158 | |
ddd42edf MB |
159 | /* |
160 | * Layout of each crypto request: | |
161 | * | |
162 | * struct ablkcipher_request | |
163 | * context | |
164 | * padding | |
165 | * struct dm_crypt_request | |
166 | * padding | |
167 | * IV | |
168 | * | |
169 | * The padding is added so that dm_crypt_request and the IV are | |
170 | * correctly aligned. | |
171 | */ | |
172 | unsigned int dmreq_start; | |
ddd42edf | 173 | |
298a9fa0 MP |
174 | unsigned int per_bio_data_size; |
175 | ||
e48d4bbf | 176 | unsigned long flags; |
1da177e4 | 177 | unsigned int key_size; |
da31a078 MB |
178 | unsigned int key_parts; /* independent parts in key buffer */ |
179 | unsigned int key_extra_size; /* additional keys length */ | |
1da177e4 LT |
180 | u8 key[0]; |
181 | }; | |
182 | ||
6a24c718 | 183 | #define MIN_IOS 16 |
1da177e4 | 184 | |
028867ac | 185 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 186 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
2dc5327d | 187 | static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq); |
027581f3 | 188 | |
c0297721 AK |
189 | /* |
190 | * Use this to access cipher attributes that are the same for each CPU. | |
191 | */ | |
192 | static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc) | |
193 | { | |
fd2d231f | 194 | return cc->tfms[0]; |
c0297721 AK |
195 | } |
196 | ||
1da177e4 LT |
197 | /* |
198 | * Different IV generation algorithms: | |
199 | * | |
3c164bd8 | 200 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 201 | * number, padded with zeros if necessary. |
1da177e4 | 202 | * |
61afef61 MB |
203 | * plain64: the initial vector is the 64-bit little-endian version of the sector |
204 | * number, padded with zeros if necessary. | |
205 | * | |
3c164bd8 RS |
206 | * essiv: "encrypted sector|salt initial vector", the sector number is |
207 | * encrypted with the bulk cipher using a salt as key. The salt | |
208 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 209 | * |
48527fa7 RS |
210 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
211 | * (needed for LRW-32-AES and possible other narrow block modes) | |
212 | * | |
46b47730 LN |
213 | * null: the initial vector is always zero. Provides compatibility with |
214 | * obsolete loop_fish2 devices. Do not use for new devices. | |
215 | * | |
34745785 MB |
216 | * lmk: Compatible implementation of the block chaining mode used |
217 | * by the Loop-AES block device encryption system | |
218 | * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ | |
219 | * It operates on full 512 byte sectors and uses CBC | |
220 | * with an IV derived from the sector number, the data and | |
221 | * optionally extra IV seed. | |
222 | * This means that after decryption the first block | |
223 | * of sector must be tweaked according to decrypted data. | |
224 | * Loop-AES can use three encryption schemes: | |
225 | * version 1: is plain aes-cbc mode | |
226 | * version 2: uses 64 multikey scheme with lmk IV generator | |
227 | * version 3: the same as version 2 with additional IV seed | |
228 | * (it uses 65 keys, last key is used as IV seed) | |
229 | * | |
ed04d981 MB |
230 | * tcw: Compatible implementation of the block chaining mode used |
231 | * by the TrueCrypt device encryption system (prior to version 4.1). | |
e44f23b3 | 232 | * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat |
ed04d981 MB |
233 | * It operates on full 512 byte sectors and uses CBC |
234 | * with an IV derived from initial key and the sector number. | |
235 | * In addition, whitening value is applied on every sector, whitening | |
236 | * is calculated from initial key, sector number and mixed using CRC32. | |
237 | * Note that this encryption scheme is vulnerable to watermarking attacks | |
238 | * and should be used for old compatible containers access only. | |
239 | * | |
1da177e4 LT |
240 | * plumb: unimplemented, see: |
241 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
242 | */ | |
243 | ||
2dc5327d MB |
244 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, |
245 | struct dm_crypt_request *dmreq) | |
1da177e4 LT |
246 | { |
247 | memset(iv, 0, cc->iv_size); | |
283a8328 | 248 | *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); |
1da177e4 LT |
249 | |
250 | return 0; | |
251 | } | |
252 | ||
61afef61 | 253 | static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, |
2dc5327d | 254 | struct dm_crypt_request *dmreq) |
61afef61 MB |
255 | { |
256 | memset(iv, 0, cc->iv_size); | |
283a8328 | 257 | *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); |
61afef61 MB |
258 | |
259 | return 0; | |
260 | } | |
261 | ||
b95bf2d3 MB |
262 | /* Initialise ESSIV - compute salt but no local memory allocations */ |
263 | static int crypt_iv_essiv_init(struct crypt_config *cc) | |
264 | { | |
265 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
266 | struct hash_desc desc; | |
267 | struct scatterlist sg; | |
c0297721 | 268 | struct crypto_cipher *essiv_tfm; |
fd2d231f | 269 | int err; |
b95bf2d3 MB |
270 | |
271 | sg_init_one(&sg, cc->key, cc->key_size); | |
272 | desc.tfm = essiv->hash_tfm; | |
273 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
274 | ||
275 | err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt); | |
276 | if (err) | |
277 | return err; | |
278 | ||
fd2d231f | 279 | essiv_tfm = cc->iv_private; |
c0297721 | 280 | |
fd2d231f MP |
281 | err = crypto_cipher_setkey(essiv_tfm, essiv->salt, |
282 | crypto_hash_digestsize(essiv->hash_tfm)); | |
283 | if (err) | |
284 | return err; | |
c0297721 AK |
285 | |
286 | return 0; | |
b95bf2d3 MB |
287 | } |
288 | ||
542da317 MB |
289 | /* Wipe salt and reset key derived from volume key */ |
290 | static int crypt_iv_essiv_wipe(struct crypt_config *cc) | |
291 | { | |
292 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
293 | unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm); | |
c0297721 | 294 | struct crypto_cipher *essiv_tfm; |
fd2d231f | 295 | int r, err = 0; |
542da317 MB |
296 | |
297 | memset(essiv->salt, 0, salt_size); | |
298 | ||
fd2d231f MP |
299 | essiv_tfm = cc->iv_private; |
300 | r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size); | |
301 | if (r) | |
302 | err = r; | |
c0297721 AK |
303 | |
304 | return err; | |
305 | } | |
306 | ||
307 | /* Set up per cpu cipher state */ | |
308 | static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc, | |
309 | struct dm_target *ti, | |
310 | u8 *salt, unsigned saltsize) | |
311 | { | |
312 | struct crypto_cipher *essiv_tfm; | |
313 | int err; | |
314 | ||
315 | /* Setup the essiv_tfm with the given salt */ | |
316 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); | |
317 | if (IS_ERR(essiv_tfm)) { | |
318 | ti->error = "Error allocating crypto tfm for ESSIV"; | |
319 | return essiv_tfm; | |
320 | } | |
321 | ||
322 | if (crypto_cipher_blocksize(essiv_tfm) != | |
323 | crypto_ablkcipher_ivsize(any_tfm(cc))) { | |
324 | ti->error = "Block size of ESSIV cipher does " | |
325 | "not match IV size of block cipher"; | |
326 | crypto_free_cipher(essiv_tfm); | |
327 | return ERR_PTR(-EINVAL); | |
328 | } | |
329 | ||
330 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); | |
331 | if (err) { | |
332 | ti->error = "Failed to set key for ESSIV cipher"; | |
333 | crypto_free_cipher(essiv_tfm); | |
334 | return ERR_PTR(err); | |
335 | } | |
336 | ||
337 | return essiv_tfm; | |
542da317 MB |
338 | } |
339 | ||
60473592 MB |
340 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) |
341 | { | |
c0297721 | 342 | struct crypto_cipher *essiv_tfm; |
60473592 MB |
343 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; |
344 | ||
b95bf2d3 MB |
345 | crypto_free_hash(essiv->hash_tfm); |
346 | essiv->hash_tfm = NULL; | |
347 | ||
348 | kzfree(essiv->salt); | |
349 | essiv->salt = NULL; | |
c0297721 | 350 | |
fd2d231f | 351 | essiv_tfm = cc->iv_private; |
c0297721 | 352 | |
fd2d231f MP |
353 | if (essiv_tfm) |
354 | crypto_free_cipher(essiv_tfm); | |
c0297721 | 355 | |
fd2d231f | 356 | cc->iv_private = NULL; |
60473592 MB |
357 | } |
358 | ||
1da177e4 | 359 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, |
d469f841 | 360 | const char *opts) |
1da177e4 | 361 | { |
5861f1be MB |
362 | struct crypto_cipher *essiv_tfm = NULL; |
363 | struct crypto_hash *hash_tfm = NULL; | |
5861f1be | 364 | u8 *salt = NULL; |
fd2d231f | 365 | int err; |
1da177e4 | 366 | |
5861f1be | 367 | if (!opts) { |
72d94861 | 368 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
369 | return -EINVAL; |
370 | } | |
371 | ||
b95bf2d3 | 372 | /* Allocate hash algorithm */ |
35058687 HX |
373 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
374 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 375 | ti->error = "Error initializing ESSIV hash"; |
5861f1be MB |
376 | err = PTR_ERR(hash_tfm); |
377 | goto bad; | |
1da177e4 LT |
378 | } |
379 | ||
b95bf2d3 | 380 | salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL); |
5861f1be | 381 | if (!salt) { |
72d94861 | 382 | ti->error = "Error kmallocing salt storage in ESSIV"; |
5861f1be MB |
383 | err = -ENOMEM; |
384 | goto bad; | |
1da177e4 LT |
385 | } |
386 | ||
b95bf2d3 | 387 | cc->iv_gen_private.essiv.salt = salt; |
b95bf2d3 MB |
388 | cc->iv_gen_private.essiv.hash_tfm = hash_tfm; |
389 | ||
fd2d231f MP |
390 | essiv_tfm = setup_essiv_cpu(cc, ti, salt, |
391 | crypto_hash_digestsize(hash_tfm)); | |
392 | if (IS_ERR(essiv_tfm)) { | |
393 | crypt_iv_essiv_dtr(cc); | |
394 | return PTR_ERR(essiv_tfm); | |
c0297721 | 395 | } |
fd2d231f | 396 | cc->iv_private = essiv_tfm; |
c0297721 | 397 | |
1da177e4 | 398 | return 0; |
5861f1be MB |
399 | |
400 | bad: | |
5861f1be MB |
401 | if (hash_tfm && !IS_ERR(hash_tfm)) |
402 | crypto_free_hash(hash_tfm); | |
b95bf2d3 | 403 | kfree(salt); |
5861f1be | 404 | return err; |
1da177e4 LT |
405 | } |
406 | ||
2dc5327d MB |
407 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, |
408 | struct dm_crypt_request *dmreq) | |
1da177e4 | 409 | { |
fd2d231f | 410 | struct crypto_cipher *essiv_tfm = cc->iv_private; |
c0297721 | 411 | |
1da177e4 | 412 | memset(iv, 0, cc->iv_size); |
283a8328 | 413 | *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); |
c0297721 AK |
414 | crypto_cipher_encrypt_one(essiv_tfm, iv, iv); |
415 | ||
1da177e4 LT |
416 | return 0; |
417 | } | |
418 | ||
48527fa7 RS |
419 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
420 | const char *opts) | |
421 | { | |
c0297721 | 422 | unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc)); |
f0d1b0b3 | 423 | int log = ilog2(bs); |
48527fa7 RS |
424 | |
425 | /* we need to calculate how far we must shift the sector count | |
426 | * to get the cipher block count, we use this shift in _gen */ | |
427 | ||
428 | if (1 << log != bs) { | |
429 | ti->error = "cypher blocksize is not a power of 2"; | |
430 | return -EINVAL; | |
431 | } | |
432 | ||
433 | if (log > 9) { | |
434 | ti->error = "cypher blocksize is > 512"; | |
435 | return -EINVAL; | |
436 | } | |
437 | ||
60473592 | 438 | cc->iv_gen_private.benbi.shift = 9 - log; |
48527fa7 RS |
439 | |
440 | return 0; | |
441 | } | |
442 | ||
443 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
444 | { | |
48527fa7 RS |
445 | } |
446 | ||
2dc5327d MB |
447 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, |
448 | struct dm_crypt_request *dmreq) | |
48527fa7 | 449 | { |
79066ad3 HX |
450 | __be64 val; |
451 | ||
48527fa7 | 452 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 | 453 | |
2dc5327d | 454 | val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); |
79066ad3 | 455 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); |
48527fa7 | 456 | |
1da177e4 LT |
457 | return 0; |
458 | } | |
459 | ||
2dc5327d MB |
460 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, |
461 | struct dm_crypt_request *dmreq) | |
46b47730 LN |
462 | { |
463 | memset(iv, 0, cc->iv_size); | |
464 | ||
465 | return 0; | |
466 | } | |
467 | ||
34745785 MB |
468 | static void crypt_iv_lmk_dtr(struct crypt_config *cc) |
469 | { | |
470 | struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; | |
471 | ||
472 | if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) | |
473 | crypto_free_shash(lmk->hash_tfm); | |
474 | lmk->hash_tfm = NULL; | |
475 | ||
476 | kzfree(lmk->seed); | |
477 | lmk->seed = NULL; | |
478 | } | |
479 | ||
480 | static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, | |
481 | const char *opts) | |
482 | { | |
483 | struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; | |
484 | ||
485 | lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0); | |
486 | if (IS_ERR(lmk->hash_tfm)) { | |
487 | ti->error = "Error initializing LMK hash"; | |
488 | return PTR_ERR(lmk->hash_tfm); | |
489 | } | |
490 | ||
491 | /* No seed in LMK version 2 */ | |
492 | if (cc->key_parts == cc->tfms_count) { | |
493 | lmk->seed = NULL; | |
494 | return 0; | |
495 | } | |
496 | ||
497 | lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); | |
498 | if (!lmk->seed) { | |
499 | crypt_iv_lmk_dtr(cc); | |
500 | ti->error = "Error kmallocing seed storage in LMK"; | |
501 | return -ENOMEM; | |
502 | } | |
503 | ||
504 | return 0; | |
505 | } | |
506 | ||
507 | static int crypt_iv_lmk_init(struct crypt_config *cc) | |
508 | { | |
509 | struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; | |
510 | int subkey_size = cc->key_size / cc->key_parts; | |
511 | ||
512 | /* LMK seed is on the position of LMK_KEYS + 1 key */ | |
513 | if (lmk->seed) | |
514 | memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), | |
515 | crypto_shash_digestsize(lmk->hash_tfm)); | |
516 | ||
517 | return 0; | |
518 | } | |
519 | ||
520 | static int crypt_iv_lmk_wipe(struct crypt_config *cc) | |
521 | { | |
522 | struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; | |
523 | ||
524 | if (lmk->seed) | |
525 | memset(lmk->seed, 0, LMK_SEED_SIZE); | |
526 | ||
527 | return 0; | |
528 | } | |
529 | ||
530 | static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, | |
531 | struct dm_crypt_request *dmreq, | |
532 | u8 *data) | |
533 | { | |
534 | struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; | |
b6106265 | 535 | SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); |
34745785 | 536 | struct md5_state md5state; |
da31a078 | 537 | __le32 buf[4]; |
34745785 MB |
538 | int i, r; |
539 | ||
b6106265 JSM |
540 | desc->tfm = lmk->hash_tfm; |
541 | desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
34745785 | 542 | |
b6106265 | 543 | r = crypto_shash_init(desc); |
34745785 MB |
544 | if (r) |
545 | return r; | |
546 | ||
547 | if (lmk->seed) { | |
b6106265 | 548 | r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); |
34745785 MB |
549 | if (r) |
550 | return r; | |
551 | } | |
552 | ||
553 | /* Sector is always 512B, block size 16, add data of blocks 1-31 */ | |
b6106265 | 554 | r = crypto_shash_update(desc, data + 16, 16 * 31); |
34745785 MB |
555 | if (r) |
556 | return r; | |
557 | ||
558 | /* Sector is cropped to 56 bits here */ | |
559 | buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); | |
560 | buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); | |
561 | buf[2] = cpu_to_le32(4024); | |
562 | buf[3] = 0; | |
b6106265 | 563 | r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); |
34745785 MB |
564 | if (r) |
565 | return r; | |
566 | ||
567 | /* No MD5 padding here */ | |
b6106265 | 568 | r = crypto_shash_export(desc, &md5state); |
34745785 MB |
569 | if (r) |
570 | return r; | |
571 | ||
572 | for (i = 0; i < MD5_HASH_WORDS; i++) | |
573 | __cpu_to_le32s(&md5state.hash[i]); | |
574 | memcpy(iv, &md5state.hash, cc->iv_size); | |
575 | ||
576 | return 0; | |
577 | } | |
578 | ||
579 | static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, | |
580 | struct dm_crypt_request *dmreq) | |
581 | { | |
582 | u8 *src; | |
583 | int r = 0; | |
584 | ||
585 | if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { | |
c2e022cb | 586 | src = kmap_atomic(sg_page(&dmreq->sg_in)); |
34745785 | 587 | r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset); |
c2e022cb | 588 | kunmap_atomic(src); |
34745785 MB |
589 | } else |
590 | memset(iv, 0, cc->iv_size); | |
591 | ||
592 | return r; | |
593 | } | |
594 | ||
595 | static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, | |
596 | struct dm_crypt_request *dmreq) | |
597 | { | |
598 | u8 *dst; | |
599 | int r; | |
600 | ||
601 | if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) | |
602 | return 0; | |
603 | ||
c2e022cb | 604 | dst = kmap_atomic(sg_page(&dmreq->sg_out)); |
34745785 MB |
605 | r = crypt_iv_lmk_one(cc, iv, dmreq, dst + dmreq->sg_out.offset); |
606 | ||
607 | /* Tweak the first block of plaintext sector */ | |
608 | if (!r) | |
609 | crypto_xor(dst + dmreq->sg_out.offset, iv, cc->iv_size); | |
610 | ||
c2e022cb | 611 | kunmap_atomic(dst); |
34745785 MB |
612 | return r; |
613 | } | |
614 | ||
ed04d981 MB |
615 | static void crypt_iv_tcw_dtr(struct crypt_config *cc) |
616 | { | |
617 | struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; | |
618 | ||
619 | kzfree(tcw->iv_seed); | |
620 | tcw->iv_seed = NULL; | |
621 | kzfree(tcw->whitening); | |
622 | tcw->whitening = NULL; | |
623 | ||
624 | if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) | |
625 | crypto_free_shash(tcw->crc32_tfm); | |
626 | tcw->crc32_tfm = NULL; | |
627 | } | |
628 | ||
629 | static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, | |
630 | const char *opts) | |
631 | { | |
632 | struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; | |
633 | ||
634 | if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { | |
635 | ti->error = "Wrong key size for TCW"; | |
636 | return -EINVAL; | |
637 | } | |
638 | ||
639 | tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0); | |
640 | if (IS_ERR(tcw->crc32_tfm)) { | |
641 | ti->error = "Error initializing CRC32 in TCW"; | |
642 | return PTR_ERR(tcw->crc32_tfm); | |
643 | } | |
644 | ||
645 | tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); | |
646 | tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); | |
647 | if (!tcw->iv_seed || !tcw->whitening) { | |
648 | crypt_iv_tcw_dtr(cc); | |
649 | ti->error = "Error allocating seed storage in TCW"; | |
650 | return -ENOMEM; | |
651 | } | |
652 | ||
653 | return 0; | |
654 | } | |
655 | ||
656 | static int crypt_iv_tcw_init(struct crypt_config *cc) | |
657 | { | |
658 | struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; | |
659 | int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; | |
660 | ||
661 | memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); | |
662 | memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], | |
663 | TCW_WHITENING_SIZE); | |
664 | ||
665 | return 0; | |
666 | } | |
667 | ||
668 | static int crypt_iv_tcw_wipe(struct crypt_config *cc) | |
669 | { | |
670 | struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; | |
671 | ||
672 | memset(tcw->iv_seed, 0, cc->iv_size); | |
673 | memset(tcw->whitening, 0, TCW_WHITENING_SIZE); | |
674 | ||
675 | return 0; | |
676 | } | |
677 | ||
678 | static int crypt_iv_tcw_whitening(struct crypt_config *cc, | |
679 | struct dm_crypt_request *dmreq, | |
680 | u8 *data) | |
681 | { | |
682 | struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; | |
683 | u64 sector = cpu_to_le64((u64)dmreq->iv_sector); | |
684 | u8 buf[TCW_WHITENING_SIZE]; | |
b6106265 | 685 | SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); |
ed04d981 MB |
686 | int i, r; |
687 | ||
688 | /* xor whitening with sector number */ | |
689 | memcpy(buf, tcw->whitening, TCW_WHITENING_SIZE); | |
690 | crypto_xor(buf, (u8 *)§or, 8); | |
691 | crypto_xor(&buf[8], (u8 *)§or, 8); | |
692 | ||
693 | /* calculate crc32 for every 32bit part and xor it */ | |
b6106265 JSM |
694 | desc->tfm = tcw->crc32_tfm; |
695 | desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
ed04d981 | 696 | for (i = 0; i < 4; i++) { |
b6106265 | 697 | r = crypto_shash_init(desc); |
ed04d981 MB |
698 | if (r) |
699 | goto out; | |
b6106265 | 700 | r = crypto_shash_update(desc, &buf[i * 4], 4); |
ed04d981 MB |
701 | if (r) |
702 | goto out; | |
b6106265 | 703 | r = crypto_shash_final(desc, &buf[i * 4]); |
ed04d981 MB |
704 | if (r) |
705 | goto out; | |
706 | } | |
707 | crypto_xor(&buf[0], &buf[12], 4); | |
708 | crypto_xor(&buf[4], &buf[8], 4); | |
709 | ||
710 | /* apply whitening (8 bytes) to whole sector */ | |
711 | for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) | |
712 | crypto_xor(data + i * 8, buf, 8); | |
713 | out: | |
1a71d6ff | 714 | memzero_explicit(buf, sizeof(buf)); |
ed04d981 MB |
715 | return r; |
716 | } | |
717 | ||
718 | static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, | |
719 | struct dm_crypt_request *dmreq) | |
720 | { | |
721 | struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; | |
722 | u64 sector = cpu_to_le64((u64)dmreq->iv_sector); | |
723 | u8 *src; | |
724 | int r = 0; | |
725 | ||
726 | /* Remove whitening from ciphertext */ | |
727 | if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { | |
728 | src = kmap_atomic(sg_page(&dmreq->sg_in)); | |
729 | r = crypt_iv_tcw_whitening(cc, dmreq, src + dmreq->sg_in.offset); | |
730 | kunmap_atomic(src); | |
731 | } | |
732 | ||
733 | /* Calculate IV */ | |
734 | memcpy(iv, tcw->iv_seed, cc->iv_size); | |
735 | crypto_xor(iv, (u8 *)§or, 8); | |
736 | if (cc->iv_size > 8) | |
737 | crypto_xor(&iv[8], (u8 *)§or, cc->iv_size - 8); | |
738 | ||
739 | return r; | |
740 | } | |
741 | ||
742 | static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, | |
743 | struct dm_crypt_request *dmreq) | |
744 | { | |
745 | u8 *dst; | |
746 | int r; | |
747 | ||
748 | if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) | |
749 | return 0; | |
750 | ||
751 | /* Apply whitening on ciphertext */ | |
752 | dst = kmap_atomic(sg_page(&dmreq->sg_out)); | |
753 | r = crypt_iv_tcw_whitening(cc, dmreq, dst + dmreq->sg_out.offset); | |
754 | kunmap_atomic(dst); | |
755 | ||
756 | return r; | |
757 | } | |
758 | ||
1da177e4 LT |
759 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
760 | .generator = crypt_iv_plain_gen | |
761 | }; | |
762 | ||
61afef61 MB |
763 | static struct crypt_iv_operations crypt_iv_plain64_ops = { |
764 | .generator = crypt_iv_plain64_gen | |
765 | }; | |
766 | ||
1da177e4 LT |
767 | static struct crypt_iv_operations crypt_iv_essiv_ops = { |
768 | .ctr = crypt_iv_essiv_ctr, | |
769 | .dtr = crypt_iv_essiv_dtr, | |
b95bf2d3 | 770 | .init = crypt_iv_essiv_init, |
542da317 | 771 | .wipe = crypt_iv_essiv_wipe, |
1da177e4 LT |
772 | .generator = crypt_iv_essiv_gen |
773 | }; | |
774 | ||
48527fa7 RS |
775 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
776 | .ctr = crypt_iv_benbi_ctr, | |
777 | .dtr = crypt_iv_benbi_dtr, | |
778 | .generator = crypt_iv_benbi_gen | |
779 | }; | |
1da177e4 | 780 | |
46b47730 LN |
781 | static struct crypt_iv_operations crypt_iv_null_ops = { |
782 | .generator = crypt_iv_null_gen | |
783 | }; | |
784 | ||
34745785 MB |
785 | static struct crypt_iv_operations crypt_iv_lmk_ops = { |
786 | .ctr = crypt_iv_lmk_ctr, | |
787 | .dtr = crypt_iv_lmk_dtr, | |
788 | .init = crypt_iv_lmk_init, | |
789 | .wipe = crypt_iv_lmk_wipe, | |
790 | .generator = crypt_iv_lmk_gen, | |
791 | .post = crypt_iv_lmk_post | |
792 | }; | |
793 | ||
ed04d981 MB |
794 | static struct crypt_iv_operations crypt_iv_tcw_ops = { |
795 | .ctr = crypt_iv_tcw_ctr, | |
796 | .dtr = crypt_iv_tcw_dtr, | |
797 | .init = crypt_iv_tcw_init, | |
798 | .wipe = crypt_iv_tcw_wipe, | |
799 | .generator = crypt_iv_tcw_gen, | |
800 | .post = crypt_iv_tcw_post | |
801 | }; | |
802 | ||
d469f841 MB |
803 | static void crypt_convert_init(struct crypt_config *cc, |
804 | struct convert_context *ctx, | |
805 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 806 | sector_t sector) |
1da177e4 LT |
807 | { |
808 | ctx->bio_in = bio_in; | |
809 | ctx->bio_out = bio_out; | |
003b5c57 KO |
810 | if (bio_in) |
811 | ctx->iter_in = bio_in->bi_iter; | |
812 | if (bio_out) | |
813 | ctx->iter_out = bio_out->bi_iter; | |
c66029f4 | 814 | ctx->cc_sector = sector + cc->iv_offset; |
43d69034 | 815 | init_completion(&ctx->restart); |
1da177e4 LT |
816 | } |
817 | ||
b2174eeb HY |
818 | static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, |
819 | struct ablkcipher_request *req) | |
820 | { | |
821 | return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
822 | } | |
823 | ||
824 | static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc, | |
825 | struct dm_crypt_request *dmreq) | |
826 | { | |
827 | return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start); | |
828 | } | |
829 | ||
2dc5327d MB |
830 | static u8 *iv_of_dmreq(struct crypt_config *cc, |
831 | struct dm_crypt_request *dmreq) | |
832 | { | |
833 | return (u8 *)ALIGN((unsigned long)(dmreq + 1), | |
834 | crypto_ablkcipher_alignmask(any_tfm(cc)) + 1); | |
835 | } | |
836 | ||
01482b76 | 837 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
838 | struct convert_context *ctx, |
839 | struct ablkcipher_request *req) | |
01482b76 | 840 | { |
003b5c57 KO |
841 | struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); |
842 | struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); | |
3a7f6c99 MB |
843 | struct dm_crypt_request *dmreq; |
844 | u8 *iv; | |
40b6229b | 845 | int r; |
3a7f6c99 | 846 | |
b2174eeb | 847 | dmreq = dmreq_of_req(cc, req); |
2dc5327d | 848 | iv = iv_of_dmreq(cc, dmreq); |
01482b76 | 849 | |
c66029f4 | 850 | dmreq->iv_sector = ctx->cc_sector; |
b2174eeb | 851 | dmreq->ctx = ctx; |
3a7f6c99 | 852 | sg_init_table(&dmreq->sg_in, 1); |
003b5c57 KO |
853 | sg_set_page(&dmreq->sg_in, bv_in.bv_page, 1 << SECTOR_SHIFT, |
854 | bv_in.bv_offset); | |
01482b76 | 855 | |
3a7f6c99 | 856 | sg_init_table(&dmreq->sg_out, 1); |
003b5c57 KO |
857 | sg_set_page(&dmreq->sg_out, bv_out.bv_page, 1 << SECTOR_SHIFT, |
858 | bv_out.bv_offset); | |
01482b76 | 859 | |
003b5c57 KO |
860 | bio_advance_iter(ctx->bio_in, &ctx->iter_in, 1 << SECTOR_SHIFT); |
861 | bio_advance_iter(ctx->bio_out, &ctx->iter_out, 1 << SECTOR_SHIFT); | |
01482b76 | 862 | |
3a7f6c99 | 863 | if (cc->iv_gen_ops) { |
2dc5327d | 864 | r = cc->iv_gen_ops->generator(cc, iv, dmreq); |
3a7f6c99 MB |
865 | if (r < 0) |
866 | return r; | |
867 | } | |
868 | ||
869 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
870 | 1 << SECTOR_SHIFT, iv); | |
871 | ||
872 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
873 | r = crypto_ablkcipher_encrypt(req); | |
874 | else | |
875 | r = crypto_ablkcipher_decrypt(req); | |
876 | ||
2dc5327d MB |
877 | if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) |
878 | r = cc->iv_gen_ops->post(cc, iv, dmreq); | |
879 | ||
3a7f6c99 | 880 | return r; |
01482b76 MB |
881 | } |
882 | ||
95497a96 MB |
883 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
884 | int error); | |
c0297721 | 885 | |
ddd42edf MB |
886 | static void crypt_alloc_req(struct crypt_config *cc, |
887 | struct convert_context *ctx) | |
888 | { | |
c66029f4 | 889 | unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1); |
c0297721 | 890 | |
610f2de3 MP |
891 | if (!ctx->req) |
892 | ctx->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
c0297721 | 893 | |
610f2de3 | 894 | ablkcipher_request_set_tfm(ctx->req, cc->tfms[key_index]); |
54cea3f6 MB |
895 | |
896 | /* | |
897 | * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs | |
898 | * requests if driver request queue is full. | |
899 | */ | |
610f2de3 | 900 | ablkcipher_request_set_callback(ctx->req, |
c0297721 | 901 | CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, |
610f2de3 | 902 | kcryptd_async_done, dmreq_of_req(cc, ctx->req)); |
ddd42edf MB |
903 | } |
904 | ||
298a9fa0 MP |
905 | static void crypt_free_req(struct crypt_config *cc, |
906 | struct ablkcipher_request *req, struct bio *base_bio) | |
907 | { | |
908 | struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); | |
909 | ||
910 | if ((struct ablkcipher_request *)(io + 1) != req) | |
911 | mempool_free(req, cc->req_pool); | |
912 | } | |
913 | ||
1da177e4 LT |
914 | /* |
915 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
916 | */ | |
917 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 918 | struct convert_context *ctx) |
1da177e4 | 919 | { |
3f1e9070 | 920 | int r; |
1da177e4 | 921 | |
40b6229b | 922 | atomic_set(&ctx->cc_pending, 1); |
c8081618 | 923 | |
003b5c57 | 924 | while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { |
1da177e4 | 925 | |
3a7f6c99 MB |
926 | crypt_alloc_req(cc, ctx); |
927 | ||
40b6229b | 928 | atomic_inc(&ctx->cc_pending); |
3f1e9070 | 929 | |
610f2de3 | 930 | r = crypt_convert_block(cc, ctx, ctx->req); |
3a7f6c99 MB |
931 | |
932 | switch (r) { | |
54cea3f6 MB |
933 | /* |
934 | * The request was queued by a crypto driver | |
935 | * but the driver request queue is full, let's wait. | |
936 | */ | |
3a7f6c99 MB |
937 | case -EBUSY: |
938 | wait_for_completion(&ctx->restart); | |
16735d02 | 939 | reinit_completion(&ctx->restart); |
54cea3f6 MB |
940 | /* fall through */ |
941 | /* | |
942 | * The request is queued and processed asynchronously, | |
943 | * completion function kcryptd_async_done() will be called. | |
944 | */ | |
c0403ec0 | 945 | case -EINPROGRESS: |
610f2de3 | 946 | ctx->req = NULL; |
c66029f4 | 947 | ctx->cc_sector++; |
3f1e9070 | 948 | continue; |
54cea3f6 MB |
949 | /* |
950 | * The request was already processed (synchronously). | |
951 | */ | |
3a7f6c99 | 952 | case 0: |
40b6229b | 953 | atomic_dec(&ctx->cc_pending); |
c66029f4 | 954 | ctx->cc_sector++; |
c7f1b204 | 955 | cond_resched(); |
3a7f6c99 | 956 | continue; |
3a7f6c99 | 957 | |
54cea3f6 | 958 | /* There was an error while processing the request. */ |
3f1e9070 | 959 | default: |
40b6229b | 960 | atomic_dec(&ctx->cc_pending); |
3f1e9070 MB |
961 | return r; |
962 | } | |
1da177e4 LT |
963 | } |
964 | ||
3f1e9070 | 965 | return 0; |
1da177e4 LT |
966 | } |
967 | ||
cf2f1abf MP |
968 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); |
969 | ||
1da177e4 LT |
970 | /* |
971 | * Generate a new unfragmented bio with the given size | |
586b286b MS |
972 | * This should never violate the device limitations (but only because |
973 | * max_segment_size is being constrained to PAGE_SIZE). | |
7145c241 MP |
974 | * |
975 | * This function may be called concurrently. If we allocate from the mempool | |
976 | * concurrently, there is a possibility of deadlock. For example, if we have | |
977 | * mempool of 256 pages, two processes, each wanting 256, pages allocate from | |
978 | * the mempool concurrently, it may deadlock in a situation where both processes | |
979 | * have allocated 128 pages and the mempool is exhausted. | |
980 | * | |
981 | * In order to avoid this scenario we allocate the pages under a mutex. | |
982 | * | |
983 | * In order to not degrade performance with excessive locking, we try | |
984 | * non-blocking allocations without a mutex first but on failure we fallback | |
985 | * to blocking allocations with a mutex. | |
1da177e4 | 986 | */ |
cf2f1abf | 987 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 988 | { |
49a8a920 | 989 | struct crypt_config *cc = io->cc; |
8b004457 | 990 | struct bio *clone; |
1da177e4 | 991 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
7145c241 MP |
992 | gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; |
993 | unsigned i, len, remaining_size; | |
91e10625 | 994 | struct page *page; |
cf2f1abf | 995 | struct bio_vec *bvec; |
1da177e4 | 996 | |
7145c241 | 997 | retry: |
d0164adc | 998 | if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) |
7145c241 MP |
999 | mutex_lock(&cc->bio_alloc_lock); |
1000 | ||
2f9941b6 | 1001 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 1002 | if (!clone) |
7145c241 | 1003 | goto return_clone; |
1da177e4 | 1004 | |
027581f3 | 1005 | clone_init(io, clone); |
6a24c718 | 1006 | |
7145c241 MP |
1007 | remaining_size = size; |
1008 | ||
f97380bc | 1009 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 | 1010 | page = mempool_alloc(cc->page_pool, gfp_mask); |
7145c241 MP |
1011 | if (!page) { |
1012 | crypt_free_buffer_pages(cc, clone); | |
1013 | bio_put(clone); | |
d0164adc | 1014 | gfp_mask |= __GFP_DIRECT_RECLAIM; |
7145c241 MP |
1015 | goto retry; |
1016 | } | |
1da177e4 | 1017 | |
7145c241 | 1018 | len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; |
91e10625 | 1019 | |
cf2f1abf MP |
1020 | bvec = &clone->bi_io_vec[clone->bi_vcnt++]; |
1021 | bvec->bv_page = page; | |
1022 | bvec->bv_len = len; | |
1023 | bvec->bv_offset = 0; | |
1da177e4 | 1024 | |
cf2f1abf | 1025 | clone->bi_iter.bi_size += len; |
1da177e4 | 1026 | |
7145c241 | 1027 | remaining_size -= len; |
1da177e4 LT |
1028 | } |
1029 | ||
7145c241 | 1030 | return_clone: |
d0164adc | 1031 | if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) |
7145c241 MP |
1032 | mutex_unlock(&cc->bio_alloc_lock); |
1033 | ||
8b004457 | 1034 | return clone; |
1da177e4 LT |
1035 | } |
1036 | ||
644bd2f0 | 1037 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 1038 | { |
644bd2f0 | 1039 | unsigned int i; |
1da177e4 LT |
1040 | struct bio_vec *bv; |
1041 | ||
cb34e057 | 1042 | bio_for_each_segment_all(bv, clone, i) { |
1da177e4 LT |
1043 | BUG_ON(!bv->bv_page); |
1044 | mempool_free(bv->bv_page, cc->page_pool); | |
1045 | bv->bv_page = NULL; | |
1046 | } | |
1047 | } | |
1048 | ||
298a9fa0 MP |
1049 | static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, |
1050 | struct bio *bio, sector_t sector) | |
dc440d1e | 1051 | { |
49a8a920 | 1052 | io->cc = cc; |
dc440d1e MB |
1053 | io->base_bio = bio; |
1054 | io->sector = sector; | |
1055 | io->error = 0; | |
610f2de3 | 1056 | io->ctx.req = NULL; |
40b6229b | 1057 | atomic_set(&io->io_pending, 0); |
dc440d1e MB |
1058 | } |
1059 | ||
3e1a8bdd MB |
1060 | static void crypt_inc_pending(struct dm_crypt_io *io) |
1061 | { | |
40b6229b | 1062 | atomic_inc(&io->io_pending); |
3e1a8bdd MB |
1063 | } |
1064 | ||
1da177e4 LT |
1065 | /* |
1066 | * One of the bios was finished. Check for completion of | |
1067 | * the whole request and correctly clean up the buffer. | |
1068 | */ | |
5742fd77 | 1069 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 1070 | { |
49a8a920 | 1071 | struct crypt_config *cc = io->cc; |
b35f8caa | 1072 | struct bio *base_bio = io->base_bio; |
b35f8caa | 1073 | int error = io->error; |
1da177e4 | 1074 | |
40b6229b | 1075 | if (!atomic_dec_and_test(&io->io_pending)) |
1da177e4 LT |
1076 | return; |
1077 | ||
610f2de3 | 1078 | if (io->ctx.req) |
298a9fa0 | 1079 | crypt_free_req(cc, io->ctx.req, base_bio); |
b35f8caa | 1080 | |
4246a0b6 CH |
1081 | base_bio->bi_error = error; |
1082 | bio_endio(base_bio); | |
1da177e4 LT |
1083 | } |
1084 | ||
1085 | /* | |
cabf08e4 | 1086 | * kcryptd/kcryptd_io: |
1da177e4 LT |
1087 | * |
1088 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 1089 | * interrupt context. |
cabf08e4 MB |
1090 | * |
1091 | * kcryptd performs the actual encryption or decryption. | |
1092 | * | |
1093 | * kcryptd_io performs the IO submission. | |
1094 | * | |
1095 | * They must be separated as otherwise the final stages could be | |
1096 | * starved by new requests which can block in the first stages due | |
1097 | * to memory allocation. | |
c0297721 AK |
1098 | * |
1099 | * The work is done per CPU global for all dm-crypt instances. | |
1100 | * They should not depend on each other and do not block. | |
1da177e4 | 1101 | */ |
4246a0b6 | 1102 | static void crypt_endio(struct bio *clone) |
8b004457 | 1103 | { |
028867ac | 1104 | struct dm_crypt_io *io = clone->bi_private; |
49a8a920 | 1105 | struct crypt_config *cc = io->cc; |
ee7a491e | 1106 | unsigned rw = bio_data_dir(clone); |
9b81c842 | 1107 | int error; |
8b004457 MB |
1108 | |
1109 | /* | |
6712ecf8 | 1110 | * free the processed pages |
8b004457 | 1111 | */ |
ee7a491e | 1112 | if (rw == WRITE) |
644bd2f0 | 1113 | crypt_free_buffer_pages(cc, clone); |
8b004457 | 1114 | |
9b81c842 | 1115 | error = clone->bi_error; |
8b004457 | 1116 | bio_put(clone); |
8b004457 | 1117 | |
9b81c842 | 1118 | if (rw == READ && !error) { |
ee7a491e MB |
1119 | kcryptd_queue_crypt(io); |
1120 | return; | |
1121 | } | |
5742fd77 | 1122 | |
9b81c842 SL |
1123 | if (unlikely(error)) |
1124 | io->error = error; | |
5742fd77 MB |
1125 | |
1126 | crypt_dec_pending(io); | |
8b004457 MB |
1127 | } |
1128 | ||
028867ac | 1129 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 | 1130 | { |
49a8a920 | 1131 | struct crypt_config *cc = io->cc; |
8b004457 MB |
1132 | |
1133 | clone->bi_private = io; | |
1134 | clone->bi_end_io = crypt_endio; | |
1135 | clone->bi_bdev = cc->dev->bdev; | |
1136 | clone->bi_rw = io->base_bio->bi_rw; | |
1137 | } | |
1138 | ||
20c82538 | 1139 | static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) |
8b004457 | 1140 | { |
49a8a920 | 1141 | struct crypt_config *cc = io->cc; |
8b004457 | 1142 | struct bio *clone; |
93e605c2 | 1143 | |
8b004457 | 1144 | /* |
59779079 MS |
1145 | * We need the original biovec array in order to decrypt |
1146 | * the whole bio data *afterwards* -- thanks to immutable | |
1147 | * biovecs we don't need to worry about the block layer | |
1148 | * modifying the biovec array; so leverage bio_clone_fast(). | |
8b004457 | 1149 | */ |
59779079 | 1150 | clone = bio_clone_fast(io->base_bio, gfp, cc->bs); |
7eaceacc | 1151 | if (!clone) |
20c82538 | 1152 | return 1; |
8b004457 | 1153 | |
20c82538 MB |
1154 | crypt_inc_pending(io); |
1155 | ||
8b004457 | 1156 | clone_init(io, clone); |
4f024f37 | 1157 | clone->bi_iter.bi_sector = cc->start + io->sector; |
8b004457 | 1158 | |
93e605c2 | 1159 | generic_make_request(clone); |
20c82538 | 1160 | return 0; |
8b004457 MB |
1161 | } |
1162 | ||
dc267621 MP |
1163 | static void kcryptd_io_read_work(struct work_struct *work) |
1164 | { | |
1165 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
1166 | ||
1167 | crypt_inc_pending(io); | |
1168 | if (kcryptd_io_read(io, GFP_NOIO)) | |
1169 | io->error = -ENOMEM; | |
1170 | crypt_dec_pending(io); | |
1171 | } | |
1172 | ||
1173 | static void kcryptd_queue_read(struct dm_crypt_io *io) | |
1174 | { | |
1175 | struct crypt_config *cc = io->cc; | |
1176 | ||
1177 | INIT_WORK(&io->work, kcryptd_io_read_work); | |
1178 | queue_work(cc->io_queue, &io->work); | |
1179 | } | |
1180 | ||
4e4eef64 MB |
1181 | static void kcryptd_io_write(struct dm_crypt_io *io) |
1182 | { | |
95497a96 | 1183 | struct bio *clone = io->ctx.bio_out; |
dc267621 | 1184 | |
95497a96 | 1185 | generic_make_request(clone); |
4e4eef64 MB |
1186 | } |
1187 | ||
b3c5fd30 MP |
1188 | #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) |
1189 | ||
dc267621 | 1190 | static int dmcrypt_write(void *data) |
395b167c | 1191 | { |
dc267621 | 1192 | struct crypt_config *cc = data; |
b3c5fd30 MP |
1193 | struct dm_crypt_io *io; |
1194 | ||
dc267621 | 1195 | while (1) { |
b3c5fd30 | 1196 | struct rb_root write_tree; |
dc267621 | 1197 | struct blk_plug plug; |
395b167c | 1198 | |
dc267621 | 1199 | DECLARE_WAITQUEUE(wait, current); |
395b167c | 1200 | |
dc267621 MP |
1201 | spin_lock_irq(&cc->write_thread_wait.lock); |
1202 | continue_locked: | |
395b167c | 1203 | |
b3c5fd30 | 1204 | if (!RB_EMPTY_ROOT(&cc->write_tree)) |
dc267621 MP |
1205 | goto pop_from_list; |
1206 | ||
bcbd94ff MP |
1207 | if (unlikely(test_bit(DM_CRYPT_EXIT_THREAD, &cc->flags))) { |
1208 | spin_unlock_irq(&cc->write_thread_wait.lock); | |
1209 | break; | |
1210 | } | |
1211 | ||
dc267621 MP |
1212 | __set_current_state(TASK_INTERRUPTIBLE); |
1213 | __add_wait_queue(&cc->write_thread_wait, &wait); | |
1214 | ||
1215 | spin_unlock_irq(&cc->write_thread_wait.lock); | |
1216 | ||
dc267621 MP |
1217 | schedule(); |
1218 | ||
dc267621 MP |
1219 | spin_lock_irq(&cc->write_thread_wait.lock); |
1220 | __remove_wait_queue(&cc->write_thread_wait, &wait); | |
1221 | goto continue_locked; | |
1222 | ||
1223 | pop_from_list: | |
b3c5fd30 MP |
1224 | write_tree = cc->write_tree; |
1225 | cc->write_tree = RB_ROOT; | |
dc267621 MP |
1226 | spin_unlock_irq(&cc->write_thread_wait.lock); |
1227 | ||
b3c5fd30 MP |
1228 | BUG_ON(rb_parent(write_tree.rb_node)); |
1229 | ||
1230 | /* | |
1231 | * Note: we cannot walk the tree here with rb_next because | |
1232 | * the structures may be freed when kcryptd_io_write is called. | |
1233 | */ | |
dc267621 MP |
1234 | blk_start_plug(&plug); |
1235 | do { | |
b3c5fd30 MP |
1236 | io = crypt_io_from_node(rb_first(&write_tree)); |
1237 | rb_erase(&io->rb_node, &write_tree); | |
dc267621 | 1238 | kcryptd_io_write(io); |
b3c5fd30 | 1239 | } while (!RB_EMPTY_ROOT(&write_tree)); |
dc267621 MP |
1240 | blk_finish_plug(&plug); |
1241 | } | |
1242 | return 0; | |
395b167c AK |
1243 | } |
1244 | ||
72c6e7af | 1245 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) |
4e4eef64 | 1246 | { |
dec1cedf | 1247 | struct bio *clone = io->ctx.bio_out; |
49a8a920 | 1248 | struct crypt_config *cc = io->cc; |
dc267621 | 1249 | unsigned long flags; |
b3c5fd30 MP |
1250 | sector_t sector; |
1251 | struct rb_node **rbp, *parent; | |
dec1cedf | 1252 | |
72c6e7af | 1253 | if (unlikely(io->error < 0)) { |
dec1cedf MB |
1254 | crypt_free_buffer_pages(cc, clone); |
1255 | bio_put(clone); | |
6c031f41 | 1256 | crypt_dec_pending(io); |
dec1cedf MB |
1257 | return; |
1258 | } | |
1259 | ||
1260 | /* crypt_convert should have filled the clone bio */ | |
003b5c57 | 1261 | BUG_ON(io->ctx.iter_out.bi_size); |
dec1cedf | 1262 | |
4f024f37 | 1263 | clone->bi_iter.bi_sector = cc->start + io->sector; |
899c95d3 | 1264 | |
0f5d8e6e MP |
1265 | if (likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) { |
1266 | generic_make_request(clone); | |
1267 | return; | |
1268 | } | |
1269 | ||
dc267621 | 1270 | spin_lock_irqsave(&cc->write_thread_wait.lock, flags); |
b3c5fd30 MP |
1271 | rbp = &cc->write_tree.rb_node; |
1272 | parent = NULL; | |
1273 | sector = io->sector; | |
1274 | while (*rbp) { | |
1275 | parent = *rbp; | |
1276 | if (sector < crypt_io_from_node(parent)->sector) | |
1277 | rbp = &(*rbp)->rb_left; | |
1278 | else | |
1279 | rbp = &(*rbp)->rb_right; | |
1280 | } | |
1281 | rb_link_node(&io->rb_node, parent, rbp); | |
1282 | rb_insert_color(&io->rb_node, &cc->write_tree); | |
1283 | ||
dc267621 MP |
1284 | wake_up_locked(&cc->write_thread_wait); |
1285 | spin_unlock_irqrestore(&cc->write_thread_wait.lock, flags); | |
4e4eef64 MB |
1286 | } |
1287 | ||
fc5a5e9a | 1288 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
8b004457 | 1289 | { |
49a8a920 | 1290 | struct crypt_config *cc = io->cc; |
8b004457 | 1291 | struct bio *clone; |
c8081618 | 1292 | int crypt_finished; |
b635b00e | 1293 | sector_t sector = io->sector; |
dec1cedf | 1294 | int r; |
8b004457 | 1295 | |
fc5a5e9a MB |
1296 | /* |
1297 | * Prevent io from disappearing until this function completes. | |
1298 | */ | |
1299 | crypt_inc_pending(io); | |
b635b00e | 1300 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector); |
fc5a5e9a | 1301 | |
cf2f1abf MP |
1302 | clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); |
1303 | if (unlikely(!clone)) { | |
1304 | io->error = -EIO; | |
1305 | goto dec; | |
1306 | } | |
c8081618 | 1307 | |
cf2f1abf MP |
1308 | io->ctx.bio_out = clone; |
1309 | io->ctx.iter_out = clone->bi_iter; | |
b635b00e | 1310 | |
cf2f1abf | 1311 | sector += bio_sectors(clone); |
93e605c2 | 1312 | |
cf2f1abf MP |
1313 | crypt_inc_pending(io); |
1314 | r = crypt_convert(cc, &io->ctx); | |
1315 | if (r) | |
1316 | io->error = -EIO; | |
1317 | crypt_finished = atomic_dec_and_test(&io->ctx.cc_pending); | |
933f01d4 | 1318 | |
cf2f1abf MP |
1319 | /* Encryption was already finished, submit io now */ |
1320 | if (crypt_finished) { | |
1321 | kcryptd_crypt_write_io_submit(io, 0); | |
1322 | io->sector = sector; | |
93e605c2 | 1323 | } |
899c95d3 | 1324 | |
cf2f1abf | 1325 | dec: |
899c95d3 | 1326 | crypt_dec_pending(io); |
84131db6 MB |
1327 | } |
1328 | ||
72c6e7af | 1329 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io) |
5742fd77 | 1330 | { |
5742fd77 MB |
1331 | crypt_dec_pending(io); |
1332 | } | |
1333 | ||
4e4eef64 | 1334 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 | 1335 | { |
49a8a920 | 1336 | struct crypt_config *cc = io->cc; |
5742fd77 | 1337 | int r = 0; |
1da177e4 | 1338 | |
3e1a8bdd | 1339 | crypt_inc_pending(io); |
3a7f6c99 | 1340 | |
53017030 | 1341 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 1342 | io->sector); |
1da177e4 | 1343 | |
5742fd77 | 1344 | r = crypt_convert(cc, &io->ctx); |
72c6e7af MP |
1345 | if (r < 0) |
1346 | io->error = -EIO; | |
5742fd77 | 1347 | |
40b6229b | 1348 | if (atomic_dec_and_test(&io->ctx.cc_pending)) |
72c6e7af | 1349 | kcryptd_crypt_read_done(io); |
3a7f6c99 MB |
1350 | |
1351 | crypt_dec_pending(io); | |
1da177e4 LT |
1352 | } |
1353 | ||
95497a96 MB |
1354 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
1355 | int error) | |
1356 | { | |
b2174eeb HY |
1357 | struct dm_crypt_request *dmreq = async_req->data; |
1358 | struct convert_context *ctx = dmreq->ctx; | |
95497a96 | 1359 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); |
49a8a920 | 1360 | struct crypt_config *cc = io->cc; |
95497a96 | 1361 | |
54cea3f6 MB |
1362 | /* |
1363 | * A request from crypto driver backlog is going to be processed now, | |
1364 | * finish the completion and continue in crypt_convert(). | |
1365 | * (Callback will be called for the second time for this request.) | |
1366 | */ | |
c0403ec0 RV |
1367 | if (error == -EINPROGRESS) { |
1368 | complete(&ctx->restart); | |
95497a96 | 1369 | return; |
c0403ec0 | 1370 | } |
95497a96 | 1371 | |
2dc5327d MB |
1372 | if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) |
1373 | error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq); | |
1374 | ||
72c6e7af MP |
1375 | if (error < 0) |
1376 | io->error = -EIO; | |
1377 | ||
298a9fa0 | 1378 | crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); |
95497a96 | 1379 | |
40b6229b | 1380 | if (!atomic_dec_and_test(&ctx->cc_pending)) |
c0403ec0 | 1381 | return; |
95497a96 MB |
1382 | |
1383 | if (bio_data_dir(io->base_bio) == READ) | |
72c6e7af | 1384 | kcryptd_crypt_read_done(io); |
95497a96 | 1385 | else |
72c6e7af | 1386 | kcryptd_crypt_write_io_submit(io, 1); |
95497a96 MB |
1387 | } |
1388 | ||
395b167c | 1389 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 1390 | { |
028867ac | 1391 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 1392 | |
cabf08e4 | 1393 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 1394 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 1395 | else |
395b167c | 1396 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
1397 | } |
1398 | ||
395b167c | 1399 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 1400 | { |
49a8a920 | 1401 | struct crypt_config *cc = io->cc; |
cabf08e4 | 1402 | |
395b167c AK |
1403 | INIT_WORK(&io->work, kcryptd_crypt); |
1404 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
1405 | } |
1406 | ||
1407 | /* | |
1408 | * Decode key from its hex representation | |
1409 | */ | |
1410 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
1411 | { | |
1412 | char buffer[3]; | |
1da177e4 LT |
1413 | unsigned int i; |
1414 | ||
1415 | buffer[2] = '\0'; | |
1416 | ||
8b004457 | 1417 | for (i = 0; i < size; i++) { |
1da177e4 LT |
1418 | buffer[0] = *hex++; |
1419 | buffer[1] = *hex++; | |
1420 | ||
1a66a08a | 1421 | if (kstrtou8(buffer, 16, &key[i])) |
1da177e4 LT |
1422 | return -EINVAL; |
1423 | } | |
1424 | ||
1425 | if (*hex != '\0') | |
1426 | return -EINVAL; | |
1427 | ||
1428 | return 0; | |
1429 | } | |
1430 | ||
fd2d231f | 1431 | static void crypt_free_tfms(struct crypt_config *cc) |
d1f96423 | 1432 | { |
d1f96423 MB |
1433 | unsigned i; |
1434 | ||
fd2d231f MP |
1435 | if (!cc->tfms) |
1436 | return; | |
1437 | ||
d1f96423 | 1438 | for (i = 0; i < cc->tfms_count; i++) |
fd2d231f MP |
1439 | if (cc->tfms[i] && !IS_ERR(cc->tfms[i])) { |
1440 | crypto_free_ablkcipher(cc->tfms[i]); | |
1441 | cc->tfms[i] = NULL; | |
d1f96423 | 1442 | } |
fd2d231f MP |
1443 | |
1444 | kfree(cc->tfms); | |
1445 | cc->tfms = NULL; | |
d1f96423 MB |
1446 | } |
1447 | ||
fd2d231f | 1448 | static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) |
d1f96423 | 1449 | { |
d1f96423 MB |
1450 | unsigned i; |
1451 | int err; | |
1452 | ||
fd2d231f MP |
1453 | cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_ablkcipher *), |
1454 | GFP_KERNEL); | |
1455 | if (!cc->tfms) | |
1456 | return -ENOMEM; | |
1457 | ||
d1f96423 | 1458 | for (i = 0; i < cc->tfms_count; i++) { |
fd2d231f MP |
1459 | cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0); |
1460 | if (IS_ERR(cc->tfms[i])) { | |
1461 | err = PTR_ERR(cc->tfms[i]); | |
1462 | crypt_free_tfms(cc); | |
d1f96423 MB |
1463 | return err; |
1464 | } | |
1465 | } | |
1466 | ||
1467 | return 0; | |
1468 | } | |
1469 | ||
c0297721 AK |
1470 | static int crypt_setkey_allcpus(struct crypt_config *cc) |
1471 | { | |
da31a078 | 1472 | unsigned subkey_size; |
fd2d231f MP |
1473 | int err = 0, i, r; |
1474 | ||
da31a078 MB |
1475 | /* Ignore extra keys (which are used for IV etc) */ |
1476 | subkey_size = (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); | |
1477 | ||
fd2d231f MP |
1478 | for (i = 0; i < cc->tfms_count; i++) { |
1479 | r = crypto_ablkcipher_setkey(cc->tfms[i], | |
1480 | cc->key + (i * subkey_size), | |
1481 | subkey_size); | |
1482 | if (r) | |
1483 | err = r; | |
c0297721 AK |
1484 | } |
1485 | ||
1486 | return err; | |
1487 | } | |
1488 | ||
e48d4bbf MB |
1489 | static int crypt_set_key(struct crypt_config *cc, char *key) |
1490 | { | |
de8be5ac MB |
1491 | int r = -EINVAL; |
1492 | int key_string_len = strlen(key); | |
1493 | ||
69a8cfcd | 1494 | /* The key size may not be changed. */ |
de8be5ac MB |
1495 | if (cc->key_size != (key_string_len >> 1)) |
1496 | goto out; | |
e48d4bbf | 1497 | |
69a8cfcd MB |
1498 | /* Hyphen (which gives a key_size of zero) means there is no key. */ |
1499 | if (!cc->key_size && strcmp(key, "-")) | |
de8be5ac | 1500 | goto out; |
e48d4bbf | 1501 | |
69a8cfcd | 1502 | if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0) |
de8be5ac | 1503 | goto out; |
e48d4bbf MB |
1504 | |
1505 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
1506 | ||
de8be5ac MB |
1507 | r = crypt_setkey_allcpus(cc); |
1508 | ||
1509 | out: | |
1510 | /* Hex key string not needed after here, so wipe it. */ | |
1511 | memset(key, '0', key_string_len); | |
1512 | ||
1513 | return r; | |
e48d4bbf MB |
1514 | } |
1515 | ||
1516 | static int crypt_wipe_key(struct crypt_config *cc) | |
1517 | { | |
1518 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
1519 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
c0297721 AK |
1520 | |
1521 | return crypt_setkey_allcpus(cc); | |
e48d4bbf MB |
1522 | } |
1523 | ||
28513fcc MB |
1524 | static void crypt_dtr(struct dm_target *ti) |
1525 | { | |
1526 | struct crypt_config *cc = ti->private; | |
1527 | ||
1528 | ti->private = NULL; | |
1529 | ||
1530 | if (!cc) | |
1531 | return; | |
1532 | ||
bcbd94ff MP |
1533 | if (cc->write_thread) { |
1534 | spin_lock_irq(&cc->write_thread_wait.lock); | |
1535 | set_bit(DM_CRYPT_EXIT_THREAD, &cc->flags); | |
1536 | wake_up_locked(&cc->write_thread_wait); | |
1537 | spin_unlock_irq(&cc->write_thread_wait.lock); | |
dc267621 | 1538 | kthread_stop(cc->write_thread); |
bcbd94ff | 1539 | } |
dc267621 | 1540 | |
28513fcc MB |
1541 | if (cc->io_queue) |
1542 | destroy_workqueue(cc->io_queue); | |
1543 | if (cc->crypt_queue) | |
1544 | destroy_workqueue(cc->crypt_queue); | |
1545 | ||
fd2d231f MP |
1546 | crypt_free_tfms(cc); |
1547 | ||
28513fcc MB |
1548 | if (cc->bs) |
1549 | bioset_free(cc->bs); | |
1550 | ||
6f65985e JL |
1551 | mempool_destroy(cc->page_pool); |
1552 | mempool_destroy(cc->req_pool); | |
28513fcc MB |
1553 | |
1554 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) | |
1555 | cc->iv_gen_ops->dtr(cc); | |
1556 | ||
28513fcc MB |
1557 | if (cc->dev) |
1558 | dm_put_device(ti, cc->dev); | |
1559 | ||
5ebaee6d | 1560 | kzfree(cc->cipher); |
7dbcd137 | 1561 | kzfree(cc->cipher_string); |
28513fcc MB |
1562 | |
1563 | /* Must zero key material before freeing */ | |
1564 | kzfree(cc); | |
1565 | } | |
1566 | ||
5ebaee6d MB |
1567 | static int crypt_ctr_cipher(struct dm_target *ti, |
1568 | char *cipher_in, char *key) | |
1da177e4 | 1569 | { |
5ebaee6d | 1570 | struct crypt_config *cc = ti->private; |
d1f96423 | 1571 | char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount; |
5ebaee6d | 1572 | char *cipher_api = NULL; |
fd2d231f | 1573 | int ret = -EINVAL; |
31998ef1 | 1574 | char dummy; |
1da177e4 | 1575 | |
5ebaee6d MB |
1576 | /* Convert to crypto api definition? */ |
1577 | if (strchr(cipher_in, '(')) { | |
1578 | ti->error = "Bad cipher specification"; | |
1da177e4 LT |
1579 | return -EINVAL; |
1580 | } | |
1581 | ||
7dbcd137 MB |
1582 | cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); |
1583 | if (!cc->cipher_string) | |
1584 | goto bad_mem; | |
1585 | ||
5ebaee6d MB |
1586 | /* |
1587 | * Legacy dm-crypt cipher specification | |
d1f96423 | 1588 | * cipher[:keycount]-mode-iv:ivopts |
5ebaee6d MB |
1589 | */ |
1590 | tmp = cipher_in; | |
d1f96423 MB |
1591 | keycount = strsep(&tmp, "-"); |
1592 | cipher = strsep(&keycount, ":"); | |
1593 | ||
1594 | if (!keycount) | |
1595 | cc->tfms_count = 1; | |
31998ef1 | 1596 | else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || |
d1f96423 MB |
1597 | !is_power_of_2(cc->tfms_count)) { |
1598 | ti->error = "Bad cipher key count specification"; | |
1599 | return -EINVAL; | |
1600 | } | |
1601 | cc->key_parts = cc->tfms_count; | |
da31a078 | 1602 | cc->key_extra_size = 0; |
5ebaee6d MB |
1603 | |
1604 | cc->cipher = kstrdup(cipher, GFP_KERNEL); | |
1605 | if (!cc->cipher) | |
1606 | goto bad_mem; | |
1607 | ||
1da177e4 LT |
1608 | chainmode = strsep(&tmp, "-"); |
1609 | ivopts = strsep(&tmp, "-"); | |
1610 | ivmode = strsep(&ivopts, ":"); | |
1611 | ||
1612 | if (tmp) | |
5ebaee6d | 1613 | DMWARN("Ignoring unexpected additional cipher options"); |
1da177e4 | 1614 | |
7dbcd137 MB |
1615 | /* |
1616 | * For compatibility with the original dm-crypt mapping format, if | |
1617 | * only the cipher name is supplied, use cbc-plain. | |
1618 | */ | |
5ebaee6d | 1619 | if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) { |
1da177e4 LT |
1620 | chainmode = "cbc"; |
1621 | ivmode = "plain"; | |
1622 | } | |
1623 | ||
d1806f6a | 1624 | if (strcmp(chainmode, "ecb") && !ivmode) { |
5ebaee6d MB |
1625 | ti->error = "IV mechanism required"; |
1626 | return -EINVAL; | |
1da177e4 LT |
1627 | } |
1628 | ||
5ebaee6d MB |
1629 | cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); |
1630 | if (!cipher_api) | |
1631 | goto bad_mem; | |
1632 | ||
1633 | ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, | |
1634 | "%s(%s)", chainmode, cipher); | |
1635 | if (ret < 0) { | |
1636 | kfree(cipher_api); | |
1637 | goto bad_mem; | |
1da177e4 LT |
1638 | } |
1639 | ||
5ebaee6d | 1640 | /* Allocate cipher */ |
fd2d231f MP |
1641 | ret = crypt_alloc_tfms(cc, cipher_api); |
1642 | if (ret < 0) { | |
1643 | ti->error = "Error allocating crypto tfm"; | |
1644 | goto bad; | |
1da177e4 | 1645 | } |
1da177e4 | 1646 | |
5ebaee6d | 1647 | /* Initialize IV */ |
c0297721 | 1648 | cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc)); |
5ebaee6d MB |
1649 | if (cc->iv_size) |
1650 | /* at least a 64 bit sector number should fit in our buffer */ | |
1651 | cc->iv_size = max(cc->iv_size, | |
1652 | (unsigned int)(sizeof(u64) / sizeof(u8))); | |
1653 | else if (ivmode) { | |
1654 | DMWARN("Selected cipher does not support IVs"); | |
1655 | ivmode = NULL; | |
1656 | } | |
1657 | ||
1658 | /* Choose ivmode, see comments at iv code. */ | |
1da177e4 LT |
1659 | if (ivmode == NULL) |
1660 | cc->iv_gen_ops = NULL; | |
1661 | else if (strcmp(ivmode, "plain") == 0) | |
1662 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
61afef61 MB |
1663 | else if (strcmp(ivmode, "plain64") == 0) |
1664 | cc->iv_gen_ops = &crypt_iv_plain64_ops; | |
1da177e4 LT |
1665 | else if (strcmp(ivmode, "essiv") == 0) |
1666 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
1667 | else if (strcmp(ivmode, "benbi") == 0) |
1668 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
1669 | else if (strcmp(ivmode, "null") == 0) |
1670 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
34745785 MB |
1671 | else if (strcmp(ivmode, "lmk") == 0) { |
1672 | cc->iv_gen_ops = &crypt_iv_lmk_ops; | |
ed04d981 MB |
1673 | /* |
1674 | * Version 2 and 3 is recognised according | |
34745785 MB |
1675 | * to length of provided multi-key string. |
1676 | * If present (version 3), last key is used as IV seed. | |
ed04d981 | 1677 | * All keys (including IV seed) are always the same size. |
34745785 | 1678 | */ |
da31a078 | 1679 | if (cc->key_size % cc->key_parts) { |
34745785 | 1680 | cc->key_parts++; |
da31a078 MB |
1681 | cc->key_extra_size = cc->key_size / cc->key_parts; |
1682 | } | |
ed04d981 MB |
1683 | } else if (strcmp(ivmode, "tcw") == 0) { |
1684 | cc->iv_gen_ops = &crypt_iv_tcw_ops; | |
1685 | cc->key_parts += 2; /* IV + whitening */ | |
1686 | cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; | |
34745785 | 1687 | } else { |
5ebaee6d | 1688 | ret = -EINVAL; |
72d94861 | 1689 | ti->error = "Invalid IV mode"; |
28513fcc | 1690 | goto bad; |
1da177e4 LT |
1691 | } |
1692 | ||
da31a078 MB |
1693 | /* Initialize and set key */ |
1694 | ret = crypt_set_key(cc, key); | |
1695 | if (ret < 0) { | |
1696 | ti->error = "Error decoding and setting key"; | |
1697 | goto bad; | |
1698 | } | |
1699 | ||
28513fcc MB |
1700 | /* Allocate IV */ |
1701 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { | |
1702 | ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); | |
1703 | if (ret < 0) { | |
1704 | ti->error = "Error creating IV"; | |
1705 | goto bad; | |
1706 | } | |
1707 | } | |
1da177e4 | 1708 | |
28513fcc MB |
1709 | /* Initialize IV (set keys for ESSIV etc) */ |
1710 | if (cc->iv_gen_ops && cc->iv_gen_ops->init) { | |
1711 | ret = cc->iv_gen_ops->init(cc); | |
1712 | if (ret < 0) { | |
1713 | ti->error = "Error initialising IV"; | |
1714 | goto bad; | |
1715 | } | |
b95bf2d3 MB |
1716 | } |
1717 | ||
5ebaee6d MB |
1718 | ret = 0; |
1719 | bad: | |
1720 | kfree(cipher_api); | |
1721 | return ret; | |
1722 | ||
1723 | bad_mem: | |
1724 | ti->error = "Cannot allocate cipher strings"; | |
1725 | return -ENOMEM; | |
1726 | } | |
1727 | ||
1728 | /* | |
1729 | * Construct an encryption mapping: | |
1730 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
1731 | */ | |
1732 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
1733 | { | |
1734 | struct crypt_config *cc; | |
772ae5f5 | 1735 | unsigned int key_size, opt_params; |
5ebaee6d MB |
1736 | unsigned long long tmpll; |
1737 | int ret; | |
d49ec52f | 1738 | size_t iv_size_padding; |
772ae5f5 MB |
1739 | struct dm_arg_set as; |
1740 | const char *opt_string; | |
31998ef1 | 1741 | char dummy; |
772ae5f5 MB |
1742 | |
1743 | static struct dm_arg _args[] = { | |
0f5d8e6e | 1744 | {0, 3, "Invalid number of feature args"}, |
772ae5f5 | 1745 | }; |
5ebaee6d | 1746 | |
772ae5f5 | 1747 | if (argc < 5) { |
5ebaee6d MB |
1748 | ti->error = "Not enough arguments"; |
1749 | return -EINVAL; | |
1da177e4 LT |
1750 | } |
1751 | ||
5ebaee6d MB |
1752 | key_size = strlen(argv[1]) >> 1; |
1753 | ||
1754 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); | |
1755 | if (!cc) { | |
1756 | ti->error = "Cannot allocate encryption context"; | |
1757 | return -ENOMEM; | |
1758 | } | |
69a8cfcd | 1759 | cc->key_size = key_size; |
5ebaee6d MB |
1760 | |
1761 | ti->private = cc; | |
1762 | ret = crypt_ctr_cipher(ti, argv[0], argv[1]); | |
1763 | if (ret < 0) | |
1764 | goto bad; | |
1765 | ||
ddd42edf | 1766 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
c0297721 | 1767 | cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc)); |
d49ec52f MP |
1768 | cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); |
1769 | ||
1770 | if (crypto_ablkcipher_alignmask(any_tfm(cc)) < CRYPTO_MINALIGN) { | |
1771 | /* Allocate the padding exactly */ | |
1772 | iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) | |
1773 | & crypto_ablkcipher_alignmask(any_tfm(cc)); | |
1774 | } else { | |
1775 | /* | |
1776 | * If the cipher requires greater alignment than kmalloc | |
1777 | * alignment, we don't know the exact position of the | |
1778 | * initialization vector. We must assume worst case. | |
1779 | */ | |
1780 | iv_size_padding = crypto_ablkcipher_alignmask(any_tfm(cc)); | |
1781 | } | |
ddd42edf | 1782 | |
94f5e024 | 1783 | ret = -ENOMEM; |
ddd42edf | 1784 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + |
d49ec52f | 1785 | sizeof(struct dm_crypt_request) + iv_size_padding + cc->iv_size); |
ddd42edf MB |
1786 | if (!cc->req_pool) { |
1787 | ti->error = "Cannot allocate crypt request mempool"; | |
28513fcc | 1788 | goto bad; |
ddd42edf | 1789 | } |
ddd42edf | 1790 | |
298a9fa0 | 1791 | cc->per_bio_data_size = ti->per_bio_data_size = |
d49ec52f MP |
1792 | ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + |
1793 | sizeof(struct dm_crypt_request) + iv_size_padding + cc->iv_size, | |
1794 | ARCH_KMALLOC_MINALIGN); | |
298a9fa0 | 1795 | |
cf2f1abf | 1796 | cc->page_pool = mempool_create_page_pool(BIO_MAX_PAGES, 0); |
1da177e4 | 1797 | if (!cc->page_pool) { |
72d94861 | 1798 | ti->error = "Cannot allocate page mempool"; |
28513fcc | 1799 | goto bad; |
1da177e4 LT |
1800 | } |
1801 | ||
bb799ca0 | 1802 | cc->bs = bioset_create(MIN_IOS, 0); |
6a24c718 MB |
1803 | if (!cc->bs) { |
1804 | ti->error = "Cannot allocate crypt bioset"; | |
28513fcc | 1805 | goto bad; |
6a24c718 MB |
1806 | } |
1807 | ||
7145c241 MP |
1808 | mutex_init(&cc->bio_alloc_lock); |
1809 | ||
28513fcc | 1810 | ret = -EINVAL; |
31998ef1 | 1811 | if (sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) { |
72d94861 | 1812 | ti->error = "Invalid iv_offset sector"; |
28513fcc | 1813 | goto bad; |
1da177e4 | 1814 | } |
4ee218cd | 1815 | cc->iv_offset = tmpll; |
1da177e4 | 1816 | |
e80d1c80 VG |
1817 | ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); |
1818 | if (ret) { | |
28513fcc MB |
1819 | ti->error = "Device lookup failed"; |
1820 | goto bad; | |
1821 | } | |
1822 | ||
e80d1c80 | 1823 | ret = -EINVAL; |
31998ef1 | 1824 | if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) { |
72d94861 | 1825 | ti->error = "Invalid device sector"; |
28513fcc | 1826 | goto bad; |
1da177e4 | 1827 | } |
4ee218cd | 1828 | cc->start = tmpll; |
1da177e4 | 1829 | |
772ae5f5 MB |
1830 | argv += 5; |
1831 | argc -= 5; | |
1832 | ||
1833 | /* Optional parameters */ | |
1834 | if (argc) { | |
1835 | as.argc = argc; | |
1836 | as.argv = argv; | |
1837 | ||
1838 | ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); | |
1839 | if (ret) | |
1840 | goto bad; | |
1841 | ||
44c144f9 | 1842 | ret = -EINVAL; |
f3396c58 MP |
1843 | while (opt_params--) { |
1844 | opt_string = dm_shift_arg(&as); | |
1845 | if (!opt_string) { | |
1846 | ti->error = "Not enough feature arguments"; | |
1847 | goto bad; | |
1848 | } | |
772ae5f5 | 1849 | |
f3396c58 MP |
1850 | if (!strcasecmp(opt_string, "allow_discards")) |
1851 | ti->num_discard_bios = 1; | |
1852 | ||
1853 | else if (!strcasecmp(opt_string, "same_cpu_crypt")) | |
1854 | set_bit(DM_CRYPT_SAME_CPU, &cc->flags); | |
1855 | ||
0f5d8e6e MP |
1856 | else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) |
1857 | set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); | |
1858 | ||
f3396c58 MP |
1859 | else { |
1860 | ti->error = "Invalid feature arguments"; | |
1861 | goto bad; | |
1862 | } | |
772ae5f5 MB |
1863 | } |
1864 | } | |
1865 | ||
28513fcc | 1866 | ret = -ENOMEM; |
670368a8 | 1867 | cc->io_queue = alloc_workqueue("kcryptd_io", WQ_MEM_RECLAIM, 1); |
cabf08e4 MB |
1868 | if (!cc->io_queue) { |
1869 | ti->error = "Couldn't create kcryptd io queue"; | |
28513fcc | 1870 | goto bad; |
cabf08e4 MB |
1871 | } |
1872 | ||
f3396c58 MP |
1873 | if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) |
1874 | cc->crypt_queue = alloc_workqueue("kcryptd", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1); | |
1875 | else | |
1876 | cc->crypt_queue = alloc_workqueue("kcryptd", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, | |
1877 | num_online_cpus()); | |
cabf08e4 | 1878 | if (!cc->crypt_queue) { |
9934a8be | 1879 | ti->error = "Couldn't create kcryptd queue"; |
28513fcc | 1880 | goto bad; |
9934a8be MB |
1881 | } |
1882 | ||
dc267621 | 1883 | init_waitqueue_head(&cc->write_thread_wait); |
b3c5fd30 | 1884 | cc->write_tree = RB_ROOT; |
dc267621 MP |
1885 | |
1886 | cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write"); | |
1887 | if (IS_ERR(cc->write_thread)) { | |
1888 | ret = PTR_ERR(cc->write_thread); | |
1889 | cc->write_thread = NULL; | |
1890 | ti->error = "Couldn't spawn write thread"; | |
1891 | goto bad; | |
1892 | } | |
1893 | wake_up_process(cc->write_thread); | |
1894 | ||
55a62eef | 1895 | ti->num_flush_bios = 1; |
0ac55489 | 1896 | ti->discard_zeroes_data_unsupported = true; |
983c7db3 | 1897 | |
1da177e4 LT |
1898 | return 0; |
1899 | ||
28513fcc MB |
1900 | bad: |
1901 | crypt_dtr(ti); | |
1902 | return ret; | |
1da177e4 LT |
1903 | } |
1904 | ||
7de3ee57 | 1905 | static int crypt_map(struct dm_target *ti, struct bio *bio) |
1da177e4 | 1906 | { |
028867ac | 1907 | struct dm_crypt_io *io; |
49a8a920 | 1908 | struct crypt_config *cc = ti->private; |
647c7db1 | 1909 | |
772ae5f5 MB |
1910 | /* |
1911 | * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues. | |
1912 | * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight | |
1913 | * - for REQ_DISCARD caller must use flush if IO ordering matters | |
1914 | */ | |
1915 | if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) { | |
647c7db1 | 1916 | bio->bi_bdev = cc->dev->bdev; |
772ae5f5 | 1917 | if (bio_sectors(bio)) |
4f024f37 KO |
1918 | bio->bi_iter.bi_sector = cc->start + |
1919 | dm_target_offset(ti, bio->bi_iter.bi_sector); | |
647c7db1 MP |
1920 | return DM_MAPIO_REMAPPED; |
1921 | } | |
1da177e4 | 1922 | |
298a9fa0 MP |
1923 | io = dm_per_bio_data(bio, cc->per_bio_data_size); |
1924 | crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); | |
1925 | io->ctx.req = (struct ablkcipher_request *)(io + 1); | |
cabf08e4 | 1926 | |
20c82538 MB |
1927 | if (bio_data_dir(io->base_bio) == READ) { |
1928 | if (kcryptd_io_read(io, GFP_NOWAIT)) | |
dc267621 | 1929 | kcryptd_queue_read(io); |
20c82538 | 1930 | } else |
cabf08e4 | 1931 | kcryptd_queue_crypt(io); |
1da177e4 | 1932 | |
d2a7ad29 | 1933 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1934 | } |
1935 | ||
fd7c092e MP |
1936 | static void crypt_status(struct dm_target *ti, status_type_t type, |
1937 | unsigned status_flags, char *result, unsigned maxlen) | |
1da177e4 | 1938 | { |
5ebaee6d | 1939 | struct crypt_config *cc = ti->private; |
fd7c092e | 1940 | unsigned i, sz = 0; |
f3396c58 | 1941 | int num_feature_args = 0; |
1da177e4 LT |
1942 | |
1943 | switch (type) { | |
1944 | case STATUSTYPE_INFO: | |
1945 | result[0] = '\0'; | |
1946 | break; | |
1947 | ||
1948 | case STATUSTYPE_TABLE: | |
7dbcd137 | 1949 | DMEMIT("%s ", cc->cipher_string); |
1da177e4 | 1950 | |
fd7c092e MP |
1951 | if (cc->key_size > 0) |
1952 | for (i = 0; i < cc->key_size; i++) | |
1953 | DMEMIT("%02x", cc->key[i]); | |
1954 | else | |
1955 | DMEMIT("-"); | |
1da177e4 | 1956 | |
4ee218cd AM |
1957 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1958 | cc->dev->name, (unsigned long long)cc->start); | |
772ae5f5 | 1959 | |
f3396c58 MP |
1960 | num_feature_args += !!ti->num_discard_bios; |
1961 | num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); | |
0f5d8e6e | 1962 | num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); |
f3396c58 MP |
1963 | if (num_feature_args) { |
1964 | DMEMIT(" %d", num_feature_args); | |
1965 | if (ti->num_discard_bios) | |
1966 | DMEMIT(" allow_discards"); | |
1967 | if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) | |
1968 | DMEMIT(" same_cpu_crypt"); | |
0f5d8e6e MP |
1969 | if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) |
1970 | DMEMIT(" submit_from_crypt_cpus"); | |
f3396c58 | 1971 | } |
772ae5f5 | 1972 | |
1da177e4 LT |
1973 | break; |
1974 | } | |
1da177e4 LT |
1975 | } |
1976 | ||
e48d4bbf MB |
1977 | static void crypt_postsuspend(struct dm_target *ti) |
1978 | { | |
1979 | struct crypt_config *cc = ti->private; | |
1980 | ||
1981 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1982 | } | |
1983 | ||
1984 | static int crypt_preresume(struct dm_target *ti) | |
1985 | { | |
1986 | struct crypt_config *cc = ti->private; | |
1987 | ||
1988 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1989 | DMERR("aborting resume - crypt key is not set."); | |
1990 | return -EAGAIN; | |
1991 | } | |
1992 | ||
1993 | return 0; | |
1994 | } | |
1995 | ||
1996 | static void crypt_resume(struct dm_target *ti) | |
1997 | { | |
1998 | struct crypt_config *cc = ti->private; | |
1999 | ||
2000 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
2001 | } | |
2002 | ||
2003 | /* Message interface | |
2004 | * key set <key> | |
2005 | * key wipe | |
2006 | */ | |
2007 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
2008 | { | |
2009 | struct crypt_config *cc = ti->private; | |
542da317 | 2010 | int ret = -EINVAL; |
e48d4bbf MB |
2011 | |
2012 | if (argc < 2) | |
2013 | goto error; | |
2014 | ||
498f0103 | 2015 | if (!strcasecmp(argv[0], "key")) { |
e48d4bbf MB |
2016 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { |
2017 | DMWARN("not suspended during key manipulation."); | |
2018 | return -EINVAL; | |
2019 | } | |
498f0103 | 2020 | if (argc == 3 && !strcasecmp(argv[1], "set")) { |
542da317 MB |
2021 | ret = crypt_set_key(cc, argv[2]); |
2022 | if (ret) | |
2023 | return ret; | |
2024 | if (cc->iv_gen_ops && cc->iv_gen_ops->init) | |
2025 | ret = cc->iv_gen_ops->init(cc); | |
2026 | return ret; | |
2027 | } | |
498f0103 | 2028 | if (argc == 2 && !strcasecmp(argv[1], "wipe")) { |
542da317 MB |
2029 | if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { |
2030 | ret = cc->iv_gen_ops->wipe(cc); | |
2031 | if (ret) | |
2032 | return ret; | |
2033 | } | |
e48d4bbf | 2034 | return crypt_wipe_key(cc); |
542da317 | 2035 | } |
e48d4bbf MB |
2036 | } |
2037 | ||
2038 | error: | |
2039 | DMWARN("unrecognised message received."); | |
2040 | return -EINVAL; | |
2041 | } | |
2042 | ||
af4874e0 MS |
2043 | static int crypt_iterate_devices(struct dm_target *ti, |
2044 | iterate_devices_callout_fn fn, void *data) | |
2045 | { | |
2046 | struct crypt_config *cc = ti->private; | |
2047 | ||
5dea271b | 2048 | return fn(ti, cc->dev, cc->start, ti->len, data); |
af4874e0 MS |
2049 | } |
2050 | ||
586b286b MS |
2051 | static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) |
2052 | { | |
2053 | /* | |
2054 | * Unfortunate constraint that is required to avoid the potential | |
2055 | * for exceeding underlying device's max_segments limits -- due to | |
2056 | * crypt_alloc_buffer() possibly allocating pages for the encryption | |
2057 | * bio that are not as physically contiguous as the original bio. | |
2058 | */ | |
2059 | limits->max_segment_size = PAGE_SIZE; | |
2060 | } | |
2061 | ||
1da177e4 LT |
2062 | static struct target_type crypt_target = { |
2063 | .name = "crypt", | |
586b286b | 2064 | .version = {1, 14, 1}, |
1da177e4 LT |
2065 | .module = THIS_MODULE, |
2066 | .ctr = crypt_ctr, | |
2067 | .dtr = crypt_dtr, | |
2068 | .map = crypt_map, | |
2069 | .status = crypt_status, | |
e48d4bbf MB |
2070 | .postsuspend = crypt_postsuspend, |
2071 | .preresume = crypt_preresume, | |
2072 | .resume = crypt_resume, | |
2073 | .message = crypt_message, | |
af4874e0 | 2074 | .iterate_devices = crypt_iterate_devices, |
586b286b | 2075 | .io_hints = crypt_io_hints, |
1da177e4 LT |
2076 | }; |
2077 | ||
2078 | static int __init dm_crypt_init(void) | |
2079 | { | |
2080 | int r; | |
2081 | ||
1da177e4 | 2082 | r = dm_register_target(&crypt_target); |
94f5e024 | 2083 | if (r < 0) |
72d94861 | 2084 | DMERR("register failed %d", r); |
1da177e4 | 2085 | |
1da177e4 LT |
2086 | return r; |
2087 | } | |
2088 | ||
2089 | static void __exit dm_crypt_exit(void) | |
2090 | { | |
10d3bd09 | 2091 | dm_unregister_target(&crypt_target); |
1da177e4 LT |
2092 | } |
2093 | ||
2094 | module_init(dm_crypt_init); | |
2095 | module_exit(dm_crypt_exit); | |
2096 | ||
bf14299f | 2097 | MODULE_AUTHOR("Jana Saout <jana@saout.de>"); |
1da177e4 LT |
2098 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); |
2099 | MODULE_LICENSE("GPL"); |