Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
542da317 | 4 | * Copyright (C) 2006-2009 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
5 | * |
6 | * This file is released under the GPL. | |
7 | */ | |
8 | ||
43d69034 | 9 | #include <linux/completion.h> |
d1806f6a | 10 | #include <linux/err.h> |
1da177e4 LT |
11 | #include <linux/module.h> |
12 | #include <linux/init.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/bio.h> | |
15 | #include <linux/blkdev.h> | |
16 | #include <linux/mempool.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/crypto.h> | |
19 | #include <linux/workqueue.h> | |
3fcfab16 | 20 | #include <linux/backing-dev.h> |
c0297721 | 21 | #include <linux/percpu.h> |
1da177e4 | 22 | #include <asm/atomic.h> |
378f058c | 23 | #include <linux/scatterlist.h> |
1da177e4 | 24 | #include <asm/page.h> |
48527fa7 | 25 | #include <asm/unaligned.h> |
1da177e4 | 26 | |
586e80e6 | 27 | #include <linux/device-mapper.h> |
1da177e4 | 28 | |
72d94861 | 29 | #define DM_MSG_PREFIX "crypt" |
e48d4bbf | 30 | #define MESG_STR(x) x, sizeof(x) |
1da177e4 | 31 | |
1da177e4 LT |
32 | /* |
33 | * context holding the current state of a multi-part conversion | |
34 | */ | |
35 | struct convert_context { | |
43d69034 | 36 | struct completion restart; |
1da177e4 LT |
37 | struct bio *bio_in; |
38 | struct bio *bio_out; | |
39 | unsigned int offset_in; | |
40 | unsigned int offset_out; | |
41 | unsigned int idx_in; | |
42 | unsigned int idx_out; | |
43 | sector_t sector; | |
43d69034 | 44 | atomic_t pending; |
1da177e4 LT |
45 | }; |
46 | ||
53017030 MB |
47 | /* |
48 | * per bio private data | |
49 | */ | |
50 | struct dm_crypt_io { | |
51 | struct dm_target *target; | |
52 | struct bio *base_bio; | |
53 | struct work_struct work; | |
54 | ||
55 | struct convert_context ctx; | |
56 | ||
57 | atomic_t pending; | |
58 | int error; | |
0c395b0f | 59 | sector_t sector; |
393b47ef | 60 | struct dm_crypt_io *base_io; |
53017030 MB |
61 | }; |
62 | ||
01482b76 | 63 | struct dm_crypt_request { |
b2174eeb | 64 | struct convert_context *ctx; |
01482b76 MB |
65 | struct scatterlist sg_in; |
66 | struct scatterlist sg_out; | |
67 | }; | |
68 | ||
1da177e4 LT |
69 | struct crypt_config; |
70 | ||
71 | struct crypt_iv_operations { | |
72 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 73 | const char *opts); |
1da177e4 | 74 | void (*dtr)(struct crypt_config *cc); |
b95bf2d3 | 75 | int (*init)(struct crypt_config *cc); |
542da317 | 76 | int (*wipe)(struct crypt_config *cc); |
1da177e4 LT |
77 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); |
78 | }; | |
79 | ||
60473592 | 80 | struct iv_essiv_private { |
b95bf2d3 MB |
81 | struct crypto_hash *hash_tfm; |
82 | u8 *salt; | |
60473592 MB |
83 | }; |
84 | ||
85 | struct iv_benbi_private { | |
86 | int shift; | |
87 | }; | |
88 | ||
1da177e4 LT |
89 | /* |
90 | * Crypt: maps a linear range of a block device | |
91 | * and encrypts / decrypts at the same time. | |
92 | */ | |
e48d4bbf | 93 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
c0297721 AK |
94 | |
95 | /* | |
96 | * Duplicated per-CPU state for cipher. | |
97 | */ | |
98 | struct crypt_cpu { | |
99 | struct ablkcipher_request *req; | |
100 | struct crypto_ablkcipher *tfm; | |
101 | ||
102 | /* ESSIV: struct crypto_cipher *essiv_tfm */ | |
103 | void *iv_private; | |
104 | }; | |
105 | ||
106 | /* | |
107 | * The fields in here must be read only after initialization, | |
108 | * changing state should be in crypt_cpu. | |
109 | */ | |
1da177e4 LT |
110 | struct crypt_config { |
111 | struct dm_dev *dev; | |
112 | sector_t start; | |
113 | ||
114 | /* | |
ddd42edf MB |
115 | * pool for per bio private data, crypto requests and |
116 | * encryption requeusts/buffer pages | |
1da177e4 LT |
117 | */ |
118 | mempool_t *io_pool; | |
ddd42edf | 119 | mempool_t *req_pool; |
1da177e4 | 120 | mempool_t *page_pool; |
6a24c718 | 121 | struct bio_set *bs; |
1da177e4 | 122 | |
cabf08e4 MB |
123 | struct workqueue_struct *io_queue; |
124 | struct workqueue_struct *crypt_queue; | |
3f1e9070 | 125 | |
5ebaee6d | 126 | char *cipher; |
7dbcd137 | 127 | char *cipher_string; |
5ebaee6d | 128 | |
1da177e4 | 129 | struct crypt_iv_operations *iv_gen_ops; |
79066ad3 | 130 | union { |
60473592 MB |
131 | struct iv_essiv_private essiv; |
132 | struct iv_benbi_private benbi; | |
79066ad3 | 133 | } iv_gen_private; |
1da177e4 LT |
134 | sector_t iv_offset; |
135 | unsigned int iv_size; | |
136 | ||
c0297721 AK |
137 | /* |
138 | * Duplicated per cpu state. Access through | |
139 | * per_cpu_ptr() only. | |
140 | */ | |
141 | struct crypt_cpu __percpu *cpu; | |
142 | ||
ddd42edf MB |
143 | /* |
144 | * Layout of each crypto request: | |
145 | * | |
146 | * struct ablkcipher_request | |
147 | * context | |
148 | * padding | |
149 | * struct dm_crypt_request | |
150 | * padding | |
151 | * IV | |
152 | * | |
153 | * The padding is added so that dm_crypt_request and the IV are | |
154 | * correctly aligned. | |
155 | */ | |
156 | unsigned int dmreq_start; | |
ddd42edf | 157 | |
e48d4bbf | 158 | unsigned long flags; |
1da177e4 LT |
159 | unsigned int key_size; |
160 | u8 key[0]; | |
161 | }; | |
162 | ||
6a24c718 | 163 | #define MIN_IOS 16 |
1da177e4 LT |
164 | #define MIN_POOL_PAGES 32 |
165 | #define MIN_BIO_PAGES 8 | |
166 | ||
e18b890b | 167 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 168 | |
028867ac | 169 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 170 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 171 | |
c0297721 AK |
172 | static struct crypt_cpu *this_crypt_config(struct crypt_config *cc) |
173 | { | |
174 | return this_cpu_ptr(cc->cpu); | |
175 | } | |
176 | ||
177 | /* | |
178 | * Use this to access cipher attributes that are the same for each CPU. | |
179 | */ | |
180 | static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc) | |
181 | { | |
182 | return __this_cpu_ptr(cc->cpu)->tfm; | |
183 | } | |
184 | ||
1da177e4 LT |
185 | /* |
186 | * Different IV generation algorithms: | |
187 | * | |
3c164bd8 | 188 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 189 | * number, padded with zeros if necessary. |
1da177e4 | 190 | * |
61afef61 MB |
191 | * plain64: the initial vector is the 64-bit little-endian version of the sector |
192 | * number, padded with zeros if necessary. | |
193 | * | |
3c164bd8 RS |
194 | * essiv: "encrypted sector|salt initial vector", the sector number is |
195 | * encrypted with the bulk cipher using a salt as key. The salt | |
196 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 197 | * |
48527fa7 RS |
198 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
199 | * (needed for LRW-32-AES and possible other narrow block modes) | |
200 | * | |
46b47730 LN |
201 | * null: the initial vector is always zero. Provides compatibility with |
202 | * obsolete loop_fish2 devices. Do not use for new devices. | |
203 | * | |
1da177e4 LT |
204 | * plumb: unimplemented, see: |
205 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
206 | */ | |
207 | ||
208 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
209 | { | |
210 | memset(iv, 0, cc->iv_size); | |
211 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
212 | ||
213 | return 0; | |
214 | } | |
215 | ||
61afef61 MB |
216 | static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, |
217 | sector_t sector) | |
218 | { | |
219 | memset(iv, 0, cc->iv_size); | |
220 | *(u64 *)iv = cpu_to_le64(sector); | |
221 | ||
222 | return 0; | |
223 | } | |
224 | ||
b95bf2d3 MB |
225 | /* Initialise ESSIV - compute salt but no local memory allocations */ |
226 | static int crypt_iv_essiv_init(struct crypt_config *cc) | |
227 | { | |
228 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
229 | struct hash_desc desc; | |
230 | struct scatterlist sg; | |
c0297721 AK |
231 | struct crypto_cipher *essiv_tfm; |
232 | int err, cpu; | |
b95bf2d3 MB |
233 | |
234 | sg_init_one(&sg, cc->key, cc->key_size); | |
235 | desc.tfm = essiv->hash_tfm; | |
236 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
237 | ||
238 | err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt); | |
239 | if (err) | |
240 | return err; | |
241 | ||
c0297721 AK |
242 | for_each_possible_cpu(cpu) { |
243 | essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private, | |
244 | ||
245 | err = crypto_cipher_setkey(essiv_tfm, essiv->salt, | |
b95bf2d3 | 246 | crypto_hash_digestsize(essiv->hash_tfm)); |
c0297721 AK |
247 | if (err) |
248 | return err; | |
249 | } | |
250 | ||
251 | return 0; | |
b95bf2d3 MB |
252 | } |
253 | ||
542da317 MB |
254 | /* Wipe salt and reset key derived from volume key */ |
255 | static int crypt_iv_essiv_wipe(struct crypt_config *cc) | |
256 | { | |
257 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
258 | unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm); | |
c0297721 AK |
259 | struct crypto_cipher *essiv_tfm; |
260 | int cpu, r, err = 0; | |
542da317 MB |
261 | |
262 | memset(essiv->salt, 0, salt_size); | |
263 | ||
c0297721 AK |
264 | for_each_possible_cpu(cpu) { |
265 | essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private; | |
266 | r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size); | |
267 | if (r) | |
268 | err = r; | |
269 | } | |
270 | ||
271 | return err; | |
272 | } | |
273 | ||
274 | /* Set up per cpu cipher state */ | |
275 | static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc, | |
276 | struct dm_target *ti, | |
277 | u8 *salt, unsigned saltsize) | |
278 | { | |
279 | struct crypto_cipher *essiv_tfm; | |
280 | int err; | |
281 | ||
282 | /* Setup the essiv_tfm with the given salt */ | |
283 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); | |
284 | if (IS_ERR(essiv_tfm)) { | |
285 | ti->error = "Error allocating crypto tfm for ESSIV"; | |
286 | return essiv_tfm; | |
287 | } | |
288 | ||
289 | if (crypto_cipher_blocksize(essiv_tfm) != | |
290 | crypto_ablkcipher_ivsize(any_tfm(cc))) { | |
291 | ti->error = "Block size of ESSIV cipher does " | |
292 | "not match IV size of block cipher"; | |
293 | crypto_free_cipher(essiv_tfm); | |
294 | return ERR_PTR(-EINVAL); | |
295 | } | |
296 | ||
297 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); | |
298 | if (err) { | |
299 | ti->error = "Failed to set key for ESSIV cipher"; | |
300 | crypto_free_cipher(essiv_tfm); | |
301 | return ERR_PTR(err); | |
302 | } | |
303 | ||
304 | return essiv_tfm; | |
542da317 MB |
305 | } |
306 | ||
60473592 MB |
307 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) |
308 | { | |
c0297721 AK |
309 | int cpu; |
310 | struct crypt_cpu *cpu_cc; | |
311 | struct crypto_cipher *essiv_tfm; | |
60473592 MB |
312 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; |
313 | ||
b95bf2d3 MB |
314 | crypto_free_hash(essiv->hash_tfm); |
315 | essiv->hash_tfm = NULL; | |
316 | ||
317 | kzfree(essiv->salt); | |
318 | essiv->salt = NULL; | |
c0297721 AK |
319 | |
320 | for_each_possible_cpu(cpu) { | |
321 | cpu_cc = per_cpu_ptr(cc->cpu, cpu); | |
322 | essiv_tfm = cpu_cc->iv_private; | |
323 | ||
324 | if (essiv_tfm) | |
325 | crypto_free_cipher(essiv_tfm); | |
326 | ||
327 | cpu_cc->iv_private = NULL; | |
328 | } | |
60473592 MB |
329 | } |
330 | ||
1da177e4 | 331 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, |
d469f841 | 332 | const char *opts) |
1da177e4 | 333 | { |
5861f1be MB |
334 | struct crypto_cipher *essiv_tfm = NULL; |
335 | struct crypto_hash *hash_tfm = NULL; | |
5861f1be | 336 | u8 *salt = NULL; |
c0297721 | 337 | int err, cpu; |
1da177e4 | 338 | |
5861f1be | 339 | if (!opts) { |
72d94861 | 340 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
341 | return -EINVAL; |
342 | } | |
343 | ||
b95bf2d3 | 344 | /* Allocate hash algorithm */ |
35058687 HX |
345 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
346 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 347 | ti->error = "Error initializing ESSIV hash"; |
5861f1be MB |
348 | err = PTR_ERR(hash_tfm); |
349 | goto bad; | |
1da177e4 LT |
350 | } |
351 | ||
b95bf2d3 | 352 | salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL); |
5861f1be | 353 | if (!salt) { |
72d94861 | 354 | ti->error = "Error kmallocing salt storage in ESSIV"; |
5861f1be MB |
355 | err = -ENOMEM; |
356 | goto bad; | |
1da177e4 LT |
357 | } |
358 | ||
b95bf2d3 | 359 | cc->iv_gen_private.essiv.salt = salt; |
b95bf2d3 MB |
360 | cc->iv_gen_private.essiv.hash_tfm = hash_tfm; |
361 | ||
c0297721 AK |
362 | for_each_possible_cpu(cpu) { |
363 | essiv_tfm = setup_essiv_cpu(cc, ti, salt, | |
364 | crypto_hash_digestsize(hash_tfm)); | |
365 | if (IS_ERR(essiv_tfm)) { | |
366 | crypt_iv_essiv_dtr(cc); | |
367 | return PTR_ERR(essiv_tfm); | |
368 | } | |
369 | per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm; | |
370 | } | |
371 | ||
1da177e4 | 372 | return 0; |
5861f1be MB |
373 | |
374 | bad: | |
5861f1be MB |
375 | if (hash_tfm && !IS_ERR(hash_tfm)) |
376 | crypto_free_hash(hash_tfm); | |
b95bf2d3 | 377 | kfree(salt); |
5861f1be | 378 | return err; |
1da177e4 LT |
379 | } |
380 | ||
1da177e4 LT |
381 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
382 | { | |
c0297721 AK |
383 | struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private; |
384 | ||
1da177e4 LT |
385 | memset(iv, 0, cc->iv_size); |
386 | *(u64 *)iv = cpu_to_le64(sector); | |
c0297721 AK |
387 | crypto_cipher_encrypt_one(essiv_tfm, iv, iv); |
388 | ||
1da177e4 LT |
389 | return 0; |
390 | } | |
391 | ||
48527fa7 RS |
392 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
393 | const char *opts) | |
394 | { | |
c0297721 | 395 | unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc)); |
f0d1b0b3 | 396 | int log = ilog2(bs); |
48527fa7 RS |
397 | |
398 | /* we need to calculate how far we must shift the sector count | |
399 | * to get the cipher block count, we use this shift in _gen */ | |
400 | ||
401 | if (1 << log != bs) { | |
402 | ti->error = "cypher blocksize is not a power of 2"; | |
403 | return -EINVAL; | |
404 | } | |
405 | ||
406 | if (log > 9) { | |
407 | ti->error = "cypher blocksize is > 512"; | |
408 | return -EINVAL; | |
409 | } | |
410 | ||
60473592 | 411 | cc->iv_gen_private.benbi.shift = 9 - log; |
48527fa7 RS |
412 | |
413 | return 0; | |
414 | } | |
415 | ||
416 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
417 | { | |
48527fa7 RS |
418 | } |
419 | ||
420 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
421 | { | |
79066ad3 HX |
422 | __be64 val; |
423 | ||
48527fa7 | 424 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 | 425 | |
60473592 | 426 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi.shift) + 1); |
79066ad3 | 427 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); |
48527fa7 | 428 | |
1da177e4 LT |
429 | return 0; |
430 | } | |
431 | ||
46b47730 LN |
432 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
433 | { | |
434 | memset(iv, 0, cc->iv_size); | |
435 | ||
436 | return 0; | |
437 | } | |
438 | ||
1da177e4 LT |
439 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
440 | .generator = crypt_iv_plain_gen | |
441 | }; | |
442 | ||
61afef61 MB |
443 | static struct crypt_iv_operations crypt_iv_plain64_ops = { |
444 | .generator = crypt_iv_plain64_gen | |
445 | }; | |
446 | ||
1da177e4 LT |
447 | static struct crypt_iv_operations crypt_iv_essiv_ops = { |
448 | .ctr = crypt_iv_essiv_ctr, | |
449 | .dtr = crypt_iv_essiv_dtr, | |
b95bf2d3 | 450 | .init = crypt_iv_essiv_init, |
542da317 | 451 | .wipe = crypt_iv_essiv_wipe, |
1da177e4 LT |
452 | .generator = crypt_iv_essiv_gen |
453 | }; | |
454 | ||
48527fa7 RS |
455 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
456 | .ctr = crypt_iv_benbi_ctr, | |
457 | .dtr = crypt_iv_benbi_dtr, | |
458 | .generator = crypt_iv_benbi_gen | |
459 | }; | |
1da177e4 | 460 | |
46b47730 LN |
461 | static struct crypt_iv_operations crypt_iv_null_ops = { |
462 | .generator = crypt_iv_null_gen | |
463 | }; | |
464 | ||
d469f841 MB |
465 | static void crypt_convert_init(struct crypt_config *cc, |
466 | struct convert_context *ctx, | |
467 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 468 | sector_t sector) |
1da177e4 LT |
469 | { |
470 | ctx->bio_in = bio_in; | |
471 | ctx->bio_out = bio_out; | |
472 | ctx->offset_in = 0; | |
473 | ctx->offset_out = 0; | |
474 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
475 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
476 | ctx->sector = sector + cc->iv_offset; | |
43d69034 | 477 | init_completion(&ctx->restart); |
1da177e4 LT |
478 | } |
479 | ||
b2174eeb HY |
480 | static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, |
481 | struct ablkcipher_request *req) | |
482 | { | |
483 | return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
484 | } | |
485 | ||
486 | static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc, | |
487 | struct dm_crypt_request *dmreq) | |
488 | { | |
489 | return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start); | |
490 | } | |
491 | ||
01482b76 | 492 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
493 | struct convert_context *ctx, |
494 | struct ablkcipher_request *req) | |
01482b76 MB |
495 | { |
496 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
497 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
3a7f6c99 MB |
498 | struct dm_crypt_request *dmreq; |
499 | u8 *iv; | |
500 | int r = 0; | |
501 | ||
b2174eeb | 502 | dmreq = dmreq_of_req(cc, req); |
3a7f6c99 | 503 | iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), |
c0297721 | 504 | crypto_ablkcipher_alignmask(any_tfm(cc)) + 1); |
01482b76 | 505 | |
b2174eeb | 506 | dmreq->ctx = ctx; |
3a7f6c99 MB |
507 | sg_init_table(&dmreq->sg_in, 1); |
508 | sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
509 | bv_in->bv_offset + ctx->offset_in); |
510 | ||
3a7f6c99 MB |
511 | sg_init_table(&dmreq->sg_out, 1); |
512 | sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
513 | bv_out->bv_offset + ctx->offset_out); |
514 | ||
515 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
516 | if (ctx->offset_in >= bv_in->bv_len) { | |
517 | ctx->offset_in = 0; | |
518 | ctx->idx_in++; | |
519 | } | |
520 | ||
521 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
522 | if (ctx->offset_out >= bv_out->bv_len) { | |
523 | ctx->offset_out = 0; | |
524 | ctx->idx_out++; | |
525 | } | |
526 | ||
3a7f6c99 MB |
527 | if (cc->iv_gen_ops) { |
528 | r = cc->iv_gen_ops->generator(cc, iv, ctx->sector); | |
529 | if (r < 0) | |
530 | return r; | |
531 | } | |
532 | ||
533 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
534 | 1 << SECTOR_SHIFT, iv); | |
535 | ||
536 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
537 | r = crypto_ablkcipher_encrypt(req); | |
538 | else | |
539 | r = crypto_ablkcipher_decrypt(req); | |
540 | ||
541 | return r; | |
01482b76 MB |
542 | } |
543 | ||
95497a96 MB |
544 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
545 | int error); | |
c0297721 | 546 | |
ddd42edf MB |
547 | static void crypt_alloc_req(struct crypt_config *cc, |
548 | struct convert_context *ctx) | |
549 | { | |
c0297721 AK |
550 | struct crypt_cpu *this_cc = this_crypt_config(cc); |
551 | ||
552 | if (!this_cc->req) | |
553 | this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
554 | ||
555 | ablkcipher_request_set_tfm(this_cc->req, this_cc->tfm); | |
556 | ablkcipher_request_set_callback(this_cc->req, | |
557 | CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP, | |
558 | kcryptd_async_done, dmreq_of_req(cc, this_cc->req)); | |
ddd42edf MB |
559 | } |
560 | ||
1da177e4 LT |
561 | /* |
562 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
563 | */ | |
564 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 565 | struct convert_context *ctx) |
1da177e4 | 566 | { |
c0297721 | 567 | struct crypt_cpu *this_cc = this_crypt_config(cc); |
3f1e9070 | 568 | int r; |
1da177e4 | 569 | |
c8081618 MB |
570 | atomic_set(&ctx->pending, 1); |
571 | ||
1da177e4 LT |
572 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && |
573 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
1da177e4 | 574 | |
3a7f6c99 MB |
575 | crypt_alloc_req(cc, ctx); |
576 | ||
3f1e9070 MB |
577 | atomic_inc(&ctx->pending); |
578 | ||
c0297721 | 579 | r = crypt_convert_block(cc, ctx, this_cc->req); |
3a7f6c99 MB |
580 | |
581 | switch (r) { | |
3f1e9070 | 582 | /* async */ |
3a7f6c99 MB |
583 | case -EBUSY: |
584 | wait_for_completion(&ctx->restart); | |
585 | INIT_COMPLETION(ctx->restart); | |
586 | /* fall through*/ | |
587 | case -EINPROGRESS: | |
c0297721 | 588 | this_cc->req = NULL; |
3f1e9070 MB |
589 | ctx->sector++; |
590 | continue; | |
591 | ||
592 | /* sync */ | |
3a7f6c99 | 593 | case 0: |
3f1e9070 | 594 | atomic_dec(&ctx->pending); |
3a7f6c99 | 595 | ctx->sector++; |
c7f1b204 | 596 | cond_resched(); |
3a7f6c99 | 597 | continue; |
3a7f6c99 | 598 | |
3f1e9070 MB |
599 | /* error */ |
600 | default: | |
601 | atomic_dec(&ctx->pending); | |
602 | return r; | |
603 | } | |
1da177e4 LT |
604 | } |
605 | ||
3f1e9070 | 606 | return 0; |
1da177e4 LT |
607 | } |
608 | ||
d469f841 MB |
609 | static void dm_crypt_bio_destructor(struct bio *bio) |
610 | { | |
028867ac | 611 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
612 | struct crypt_config *cc = io->target->private; |
613 | ||
614 | bio_free(bio, cc->bs); | |
d469f841 | 615 | } |
6a24c718 | 616 | |
1da177e4 LT |
617 | /* |
618 | * Generate a new unfragmented bio with the given size | |
619 | * This should never violate the device limitations | |
933f01d4 MB |
620 | * May return a smaller bio when running out of pages, indicated by |
621 | * *out_of_pages set to 1. | |
1da177e4 | 622 | */ |
933f01d4 MB |
623 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size, |
624 | unsigned *out_of_pages) | |
1da177e4 | 625 | { |
027581f3 | 626 | struct crypt_config *cc = io->target->private; |
8b004457 | 627 | struct bio *clone; |
1da177e4 | 628 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 629 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
630 | unsigned i, len; |
631 | struct page *page; | |
1da177e4 | 632 | |
2f9941b6 | 633 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 634 | if (!clone) |
1da177e4 | 635 | return NULL; |
1da177e4 | 636 | |
027581f3 | 637 | clone_init(io, clone); |
933f01d4 | 638 | *out_of_pages = 0; |
6a24c718 | 639 | |
f97380bc | 640 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 | 641 | page = mempool_alloc(cc->page_pool, gfp_mask); |
933f01d4 MB |
642 | if (!page) { |
643 | *out_of_pages = 1; | |
1da177e4 | 644 | break; |
933f01d4 | 645 | } |
1da177e4 LT |
646 | |
647 | /* | |
648 | * if additional pages cannot be allocated without waiting, | |
649 | * return a partially allocated bio, the caller will then try | |
650 | * to allocate additional bios while submitting this partial bio | |
651 | */ | |
f97380bc | 652 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
653 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
654 | ||
91e10625 MB |
655 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
656 | ||
657 | if (!bio_add_page(clone, page, len, 0)) { | |
658 | mempool_free(page, cc->page_pool); | |
659 | break; | |
660 | } | |
1da177e4 | 661 | |
91e10625 | 662 | size -= len; |
1da177e4 LT |
663 | } |
664 | ||
8b004457 MB |
665 | if (!clone->bi_size) { |
666 | bio_put(clone); | |
1da177e4 LT |
667 | return NULL; |
668 | } | |
669 | ||
8b004457 | 670 | return clone; |
1da177e4 LT |
671 | } |
672 | ||
644bd2f0 | 673 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 674 | { |
644bd2f0 | 675 | unsigned int i; |
1da177e4 LT |
676 | struct bio_vec *bv; |
677 | ||
644bd2f0 | 678 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 679 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
680 | BUG_ON(!bv->bv_page); |
681 | mempool_free(bv->bv_page, cc->page_pool); | |
682 | bv->bv_page = NULL; | |
683 | } | |
684 | } | |
685 | ||
dc440d1e MB |
686 | static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti, |
687 | struct bio *bio, sector_t sector) | |
688 | { | |
689 | struct crypt_config *cc = ti->private; | |
690 | struct dm_crypt_io *io; | |
691 | ||
692 | io = mempool_alloc(cc->io_pool, GFP_NOIO); | |
693 | io->target = ti; | |
694 | io->base_bio = bio; | |
695 | io->sector = sector; | |
696 | io->error = 0; | |
393b47ef | 697 | io->base_io = NULL; |
dc440d1e MB |
698 | atomic_set(&io->pending, 0); |
699 | ||
700 | return io; | |
701 | } | |
702 | ||
3e1a8bdd MB |
703 | static void crypt_inc_pending(struct dm_crypt_io *io) |
704 | { | |
705 | atomic_inc(&io->pending); | |
706 | } | |
707 | ||
1da177e4 LT |
708 | /* |
709 | * One of the bios was finished. Check for completion of | |
710 | * the whole request and correctly clean up the buffer. | |
393b47ef | 711 | * If base_io is set, wait for the last fragment to complete. |
1da177e4 | 712 | */ |
5742fd77 | 713 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 714 | { |
5742fd77 | 715 | struct crypt_config *cc = io->target->private; |
b35f8caa MB |
716 | struct bio *base_bio = io->base_bio; |
717 | struct dm_crypt_io *base_io = io->base_io; | |
718 | int error = io->error; | |
1da177e4 LT |
719 | |
720 | if (!atomic_dec_and_test(&io->pending)) | |
721 | return; | |
722 | ||
b35f8caa MB |
723 | mempool_free(io, cc->io_pool); |
724 | ||
725 | if (likely(!base_io)) | |
726 | bio_endio(base_bio, error); | |
393b47ef | 727 | else { |
b35f8caa MB |
728 | if (error && !base_io->error) |
729 | base_io->error = error; | |
730 | crypt_dec_pending(base_io); | |
393b47ef | 731 | } |
1da177e4 LT |
732 | } |
733 | ||
734 | /* | |
cabf08e4 | 735 | * kcryptd/kcryptd_io: |
1da177e4 LT |
736 | * |
737 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 738 | * interrupt context. |
cabf08e4 MB |
739 | * |
740 | * kcryptd performs the actual encryption or decryption. | |
741 | * | |
742 | * kcryptd_io performs the IO submission. | |
743 | * | |
744 | * They must be separated as otherwise the final stages could be | |
745 | * starved by new requests which can block in the first stages due | |
746 | * to memory allocation. | |
c0297721 AK |
747 | * |
748 | * The work is done per CPU global for all dm-crypt instances. | |
749 | * They should not depend on each other and do not block. | |
1da177e4 | 750 | */ |
6712ecf8 | 751 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 752 | { |
028867ac | 753 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 754 | struct crypt_config *cc = io->target->private; |
ee7a491e | 755 | unsigned rw = bio_data_dir(clone); |
8b004457 | 756 | |
adfe4770 MB |
757 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
758 | error = -EIO; | |
759 | ||
8b004457 | 760 | /* |
6712ecf8 | 761 | * free the processed pages |
8b004457 | 762 | */ |
ee7a491e | 763 | if (rw == WRITE) |
644bd2f0 | 764 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
765 | |
766 | bio_put(clone); | |
8b004457 | 767 | |
ee7a491e MB |
768 | if (rw == READ && !error) { |
769 | kcryptd_queue_crypt(io); | |
770 | return; | |
771 | } | |
5742fd77 MB |
772 | |
773 | if (unlikely(error)) | |
774 | io->error = error; | |
775 | ||
776 | crypt_dec_pending(io); | |
8b004457 MB |
777 | } |
778 | ||
028867ac | 779 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
780 | { |
781 | struct crypt_config *cc = io->target->private; | |
782 | ||
783 | clone->bi_private = io; | |
784 | clone->bi_end_io = crypt_endio; | |
785 | clone->bi_bdev = cc->dev->bdev; | |
786 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 787 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
788 | } |
789 | ||
4e4eef64 | 790 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
791 | { |
792 | struct crypt_config *cc = io->target->private; | |
793 | struct bio *base_bio = io->base_bio; | |
794 | struct bio *clone; | |
93e605c2 | 795 | |
3e1a8bdd | 796 | crypt_inc_pending(io); |
8b004457 MB |
797 | |
798 | /* | |
799 | * The block layer might modify the bvec array, so always | |
800 | * copy the required bvecs because we need the original | |
801 | * one in order to decrypt the whole bio data *afterwards*. | |
802 | */ | |
6a24c718 | 803 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 804 | if (unlikely(!clone)) { |
5742fd77 MB |
805 | io->error = -ENOMEM; |
806 | crypt_dec_pending(io); | |
23541d2d | 807 | return; |
93e605c2 | 808 | } |
8b004457 MB |
809 | |
810 | clone_init(io, clone); | |
811 | clone->bi_idx = 0; | |
812 | clone->bi_vcnt = bio_segments(base_bio); | |
813 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 814 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
815 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
816 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 817 | |
93e605c2 | 818 | generic_make_request(clone); |
8b004457 MB |
819 | } |
820 | ||
4e4eef64 MB |
821 | static void kcryptd_io_write(struct dm_crypt_io *io) |
822 | { | |
95497a96 | 823 | struct bio *clone = io->ctx.bio_out; |
95497a96 | 824 | generic_make_request(clone); |
4e4eef64 MB |
825 | } |
826 | ||
395b167c AK |
827 | static void kcryptd_io(struct work_struct *work) |
828 | { | |
829 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
830 | ||
831 | if (bio_data_dir(io->base_bio) == READ) | |
832 | kcryptd_io_read(io); | |
833 | else | |
834 | kcryptd_io_write(io); | |
835 | } | |
836 | ||
837 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
838 | { | |
839 | struct crypt_config *cc = io->target->private; | |
840 | ||
841 | INIT_WORK(&io->work, kcryptd_io); | |
842 | queue_work(cc->io_queue, &io->work); | |
843 | } | |
844 | ||
95497a96 MB |
845 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
846 | int error, int async) | |
4e4eef64 | 847 | { |
dec1cedf MB |
848 | struct bio *clone = io->ctx.bio_out; |
849 | struct crypt_config *cc = io->target->private; | |
850 | ||
851 | if (unlikely(error < 0)) { | |
852 | crypt_free_buffer_pages(cc, clone); | |
853 | bio_put(clone); | |
854 | io->error = -EIO; | |
6c031f41 | 855 | crypt_dec_pending(io); |
dec1cedf MB |
856 | return; |
857 | } | |
858 | ||
859 | /* crypt_convert should have filled the clone bio */ | |
860 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
861 | ||
862 | clone->bi_sector = cc->start + io->sector; | |
899c95d3 | 863 | |
95497a96 MB |
864 | if (async) |
865 | kcryptd_queue_io(io); | |
1e37bb8e | 866 | else |
95497a96 | 867 | generic_make_request(clone); |
4e4eef64 MB |
868 | } |
869 | ||
fc5a5e9a | 870 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
8b004457 MB |
871 | { |
872 | struct crypt_config *cc = io->target->private; | |
8b004457 | 873 | struct bio *clone; |
393b47ef | 874 | struct dm_crypt_io *new_io; |
c8081618 | 875 | int crypt_finished; |
933f01d4 | 876 | unsigned out_of_pages = 0; |
dec1cedf | 877 | unsigned remaining = io->base_bio->bi_size; |
b635b00e | 878 | sector_t sector = io->sector; |
dec1cedf | 879 | int r; |
8b004457 | 880 | |
fc5a5e9a MB |
881 | /* |
882 | * Prevent io from disappearing until this function completes. | |
883 | */ | |
884 | crypt_inc_pending(io); | |
b635b00e | 885 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector); |
fc5a5e9a | 886 | |
93e605c2 MB |
887 | /* |
888 | * The allocated buffers can be smaller than the whole bio, | |
889 | * so repeat the whole process until all the data can be handled. | |
890 | */ | |
891 | while (remaining) { | |
933f01d4 | 892 | clone = crypt_alloc_buffer(io, remaining, &out_of_pages); |
23541d2d | 893 | if (unlikely(!clone)) { |
5742fd77 | 894 | io->error = -ENOMEM; |
fc5a5e9a | 895 | break; |
23541d2d | 896 | } |
93e605c2 | 897 | |
53017030 MB |
898 | io->ctx.bio_out = clone; |
899 | io->ctx.idx_out = 0; | |
93e605c2 | 900 | |
dec1cedf | 901 | remaining -= clone->bi_size; |
b635b00e | 902 | sector += bio_sectors(clone); |
93e605c2 | 903 | |
4e594098 | 904 | crypt_inc_pending(io); |
dec1cedf | 905 | r = crypt_convert(cc, &io->ctx); |
c8081618 | 906 | crypt_finished = atomic_dec_and_test(&io->ctx.pending); |
f97380bc | 907 | |
c8081618 MB |
908 | /* Encryption was already finished, submit io now */ |
909 | if (crypt_finished) { | |
3a7f6c99 | 910 | kcryptd_crypt_write_io_submit(io, r, 0); |
c8081618 MB |
911 | |
912 | /* | |
913 | * If there was an error, do not try next fragments. | |
914 | * For async, error is processed in async handler. | |
915 | */ | |
6c031f41 | 916 | if (unlikely(r < 0)) |
fc5a5e9a | 917 | break; |
b635b00e MB |
918 | |
919 | io->sector = sector; | |
4e594098 | 920 | } |
93e605c2 | 921 | |
933f01d4 MB |
922 | /* |
923 | * Out of memory -> run queues | |
924 | * But don't wait if split was due to the io size restriction | |
925 | */ | |
926 | if (unlikely(out_of_pages)) | |
8aa7e847 | 927 | congestion_wait(BLK_RW_ASYNC, HZ/100); |
933f01d4 | 928 | |
393b47ef MB |
929 | /* |
930 | * With async crypto it is unsafe to share the crypto context | |
931 | * between fragments, so switch to a new dm_crypt_io structure. | |
932 | */ | |
933 | if (unlikely(!crypt_finished && remaining)) { | |
934 | new_io = crypt_io_alloc(io->target, io->base_bio, | |
935 | sector); | |
936 | crypt_inc_pending(new_io); | |
937 | crypt_convert_init(cc, &new_io->ctx, NULL, | |
938 | io->base_bio, sector); | |
939 | new_io->ctx.idx_in = io->ctx.idx_in; | |
940 | new_io->ctx.offset_in = io->ctx.offset_in; | |
941 | ||
942 | /* | |
943 | * Fragments after the first use the base_io | |
944 | * pending count. | |
945 | */ | |
946 | if (!io->base_io) | |
947 | new_io->base_io = io; | |
948 | else { | |
949 | new_io->base_io = io->base_io; | |
950 | crypt_inc_pending(io->base_io); | |
951 | crypt_dec_pending(io); | |
952 | } | |
953 | ||
954 | io = new_io; | |
955 | } | |
93e605c2 | 956 | } |
899c95d3 MB |
957 | |
958 | crypt_dec_pending(io); | |
84131db6 MB |
959 | } |
960 | ||
4e4eef64 | 961 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
962 | { |
963 | if (unlikely(error < 0)) | |
964 | io->error = -EIO; | |
965 | ||
966 | crypt_dec_pending(io); | |
967 | } | |
968 | ||
4e4eef64 | 969 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
970 | { |
971 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 972 | int r = 0; |
1da177e4 | 973 | |
3e1a8bdd | 974 | crypt_inc_pending(io); |
3a7f6c99 | 975 | |
53017030 | 976 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 977 | io->sector); |
1da177e4 | 978 | |
5742fd77 MB |
979 | r = crypt_convert(cc, &io->ctx); |
980 | ||
3f1e9070 | 981 | if (atomic_dec_and_test(&io->ctx.pending)) |
3a7f6c99 MB |
982 | kcryptd_crypt_read_done(io, r); |
983 | ||
984 | crypt_dec_pending(io); | |
1da177e4 LT |
985 | } |
986 | ||
95497a96 MB |
987 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
988 | int error) | |
989 | { | |
b2174eeb HY |
990 | struct dm_crypt_request *dmreq = async_req->data; |
991 | struct convert_context *ctx = dmreq->ctx; | |
95497a96 MB |
992 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); |
993 | struct crypt_config *cc = io->target->private; | |
994 | ||
995 | if (error == -EINPROGRESS) { | |
996 | complete(&ctx->restart); | |
997 | return; | |
998 | } | |
999 | ||
b2174eeb | 1000 | mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool); |
95497a96 MB |
1001 | |
1002 | if (!atomic_dec_and_test(&ctx->pending)) | |
1003 | return; | |
1004 | ||
1005 | if (bio_data_dir(io->base_bio) == READ) | |
1006 | kcryptd_crypt_read_done(io, error); | |
1007 | else | |
1008 | kcryptd_crypt_write_io_submit(io, error, 1); | |
1009 | } | |
1010 | ||
395b167c | 1011 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 1012 | { |
028867ac | 1013 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 1014 | |
cabf08e4 | 1015 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 1016 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 1017 | else |
395b167c | 1018 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
1019 | } |
1020 | ||
395b167c | 1021 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 1022 | { |
395b167c | 1023 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 1024 | |
395b167c AK |
1025 | INIT_WORK(&io->work, kcryptd_crypt); |
1026 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
1027 | } |
1028 | ||
1029 | /* | |
1030 | * Decode key from its hex representation | |
1031 | */ | |
1032 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
1033 | { | |
1034 | char buffer[3]; | |
1035 | char *endp; | |
1036 | unsigned int i; | |
1037 | ||
1038 | buffer[2] = '\0'; | |
1039 | ||
8b004457 | 1040 | for (i = 0; i < size; i++) { |
1da177e4 LT |
1041 | buffer[0] = *hex++; |
1042 | buffer[1] = *hex++; | |
1043 | ||
1044 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
1045 | ||
1046 | if (endp != &buffer[2]) | |
1047 | return -EINVAL; | |
1048 | } | |
1049 | ||
1050 | if (*hex != '\0') | |
1051 | return -EINVAL; | |
1052 | ||
1053 | return 0; | |
1054 | } | |
1055 | ||
1056 | /* | |
1057 | * Encode key into its hex representation | |
1058 | */ | |
1059 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
1060 | { | |
1061 | unsigned int i; | |
1062 | ||
8b004457 | 1063 | for (i = 0; i < size; i++) { |
1da177e4 LT |
1064 | sprintf(hex, "%02x", *key); |
1065 | hex += 2; | |
1066 | key++; | |
1067 | } | |
1068 | } | |
1069 | ||
c0297721 AK |
1070 | static int crypt_setkey_allcpus(struct crypt_config *cc) |
1071 | { | |
1072 | int cpu, err = 0, r; | |
1073 | ||
1074 | for_each_possible_cpu(cpu) { | |
1075 | r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfm, | |
1076 | cc->key, cc->key_size); | |
1077 | if (r) | |
1078 | err = r; | |
1079 | } | |
1080 | ||
1081 | return err; | |
1082 | } | |
1083 | ||
e48d4bbf MB |
1084 | static int crypt_set_key(struct crypt_config *cc, char *key) |
1085 | { | |
69a8cfcd MB |
1086 | /* The key size may not be changed. */ |
1087 | if (cc->key_size != (strlen(key) >> 1)) | |
e48d4bbf MB |
1088 | return -EINVAL; |
1089 | ||
69a8cfcd MB |
1090 | /* Hyphen (which gives a key_size of zero) means there is no key. */ |
1091 | if (!cc->key_size && strcmp(key, "-")) | |
1092 | return -EINVAL; | |
e48d4bbf | 1093 | |
69a8cfcd | 1094 | if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0) |
e48d4bbf MB |
1095 | return -EINVAL; |
1096 | ||
1097 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
1098 | ||
c0297721 | 1099 | return crypt_setkey_allcpus(cc); |
e48d4bbf MB |
1100 | } |
1101 | ||
1102 | static int crypt_wipe_key(struct crypt_config *cc) | |
1103 | { | |
1104 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
1105 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
c0297721 AK |
1106 | |
1107 | return crypt_setkey_allcpus(cc); | |
e48d4bbf MB |
1108 | } |
1109 | ||
28513fcc MB |
1110 | static void crypt_dtr(struct dm_target *ti) |
1111 | { | |
1112 | struct crypt_config *cc = ti->private; | |
c0297721 AK |
1113 | struct crypt_cpu *cpu_cc; |
1114 | int cpu; | |
28513fcc MB |
1115 | |
1116 | ti->private = NULL; | |
1117 | ||
1118 | if (!cc) | |
1119 | return; | |
1120 | ||
1121 | if (cc->io_queue) | |
1122 | destroy_workqueue(cc->io_queue); | |
1123 | if (cc->crypt_queue) | |
1124 | destroy_workqueue(cc->crypt_queue); | |
1125 | ||
c0297721 AK |
1126 | if (cc->cpu) |
1127 | for_each_possible_cpu(cpu) { | |
1128 | cpu_cc = per_cpu_ptr(cc->cpu, cpu); | |
1129 | if (cpu_cc->req) | |
1130 | mempool_free(cpu_cc->req, cc->req_pool); | |
1131 | if (cpu_cc->tfm) | |
1132 | crypto_free_ablkcipher(cpu_cc->tfm); | |
1133 | } | |
1134 | ||
28513fcc MB |
1135 | if (cc->bs) |
1136 | bioset_free(cc->bs); | |
1137 | ||
1138 | if (cc->page_pool) | |
1139 | mempool_destroy(cc->page_pool); | |
1140 | if (cc->req_pool) | |
1141 | mempool_destroy(cc->req_pool); | |
1142 | if (cc->io_pool) | |
1143 | mempool_destroy(cc->io_pool); | |
1144 | ||
1145 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) | |
1146 | cc->iv_gen_ops->dtr(cc); | |
1147 | ||
28513fcc MB |
1148 | if (cc->dev) |
1149 | dm_put_device(ti, cc->dev); | |
1150 | ||
c0297721 AK |
1151 | if (cc->cpu) |
1152 | free_percpu(cc->cpu); | |
1153 | ||
5ebaee6d | 1154 | kzfree(cc->cipher); |
7dbcd137 | 1155 | kzfree(cc->cipher_string); |
28513fcc MB |
1156 | |
1157 | /* Must zero key material before freeing */ | |
1158 | kzfree(cc); | |
1159 | } | |
1160 | ||
5ebaee6d MB |
1161 | static int crypt_ctr_cipher(struct dm_target *ti, |
1162 | char *cipher_in, char *key) | |
1da177e4 | 1163 | { |
5ebaee6d | 1164 | struct crypt_config *cc = ti->private; |
c0297721 | 1165 | struct crypto_ablkcipher *tfm; |
5ebaee6d MB |
1166 | char *tmp, *cipher, *chainmode, *ivmode, *ivopts; |
1167 | char *cipher_api = NULL; | |
c0297721 | 1168 | int cpu, ret = -EINVAL; |
1da177e4 | 1169 | |
5ebaee6d MB |
1170 | /* Convert to crypto api definition? */ |
1171 | if (strchr(cipher_in, '(')) { | |
1172 | ti->error = "Bad cipher specification"; | |
1da177e4 LT |
1173 | return -EINVAL; |
1174 | } | |
1175 | ||
7dbcd137 MB |
1176 | cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); |
1177 | if (!cc->cipher_string) | |
1178 | goto bad_mem; | |
1179 | ||
5ebaee6d MB |
1180 | /* |
1181 | * Legacy dm-crypt cipher specification | |
1182 | * cipher-mode-iv:ivopts | |
1183 | */ | |
1184 | tmp = cipher_in; | |
1da177e4 | 1185 | cipher = strsep(&tmp, "-"); |
5ebaee6d MB |
1186 | |
1187 | cc->cipher = kstrdup(cipher, GFP_KERNEL); | |
1188 | if (!cc->cipher) | |
1189 | goto bad_mem; | |
1190 | ||
1da177e4 LT |
1191 | chainmode = strsep(&tmp, "-"); |
1192 | ivopts = strsep(&tmp, "-"); | |
1193 | ivmode = strsep(&ivopts, ":"); | |
1194 | ||
1195 | if (tmp) | |
5ebaee6d | 1196 | DMWARN("Ignoring unexpected additional cipher options"); |
1da177e4 | 1197 | |
c0297721 AK |
1198 | cc->cpu = alloc_percpu(struct crypt_cpu); |
1199 | if (!cc->cpu) { | |
1200 | ti->error = "Cannot allocate per cpu state"; | |
1201 | goto bad_mem; | |
1202 | } | |
1203 | ||
7dbcd137 MB |
1204 | /* |
1205 | * For compatibility with the original dm-crypt mapping format, if | |
1206 | * only the cipher name is supplied, use cbc-plain. | |
1207 | */ | |
5ebaee6d | 1208 | if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) { |
1da177e4 LT |
1209 | chainmode = "cbc"; |
1210 | ivmode = "plain"; | |
1211 | } | |
1212 | ||
d1806f6a | 1213 | if (strcmp(chainmode, "ecb") && !ivmode) { |
5ebaee6d MB |
1214 | ti->error = "IV mechanism required"; |
1215 | return -EINVAL; | |
1da177e4 LT |
1216 | } |
1217 | ||
5ebaee6d MB |
1218 | cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); |
1219 | if (!cipher_api) | |
1220 | goto bad_mem; | |
1221 | ||
1222 | ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, | |
1223 | "%s(%s)", chainmode, cipher); | |
1224 | if (ret < 0) { | |
1225 | kfree(cipher_api); | |
1226 | goto bad_mem; | |
1da177e4 LT |
1227 | } |
1228 | ||
5ebaee6d | 1229 | /* Allocate cipher */ |
c0297721 AK |
1230 | for_each_possible_cpu(cpu) { |
1231 | tfm = crypto_alloc_ablkcipher(cipher_api, 0, 0); | |
1232 | if (IS_ERR(tfm)) { | |
1233 | ret = PTR_ERR(tfm); | |
1234 | ti->error = "Error allocating crypto tfm"; | |
1235 | goto bad; | |
1236 | } | |
1237 | per_cpu_ptr(cc->cpu, cpu)->tfm = tfm; | |
1da177e4 | 1238 | } |
1da177e4 | 1239 | |
5ebaee6d MB |
1240 | /* Initialize and set key */ |
1241 | ret = crypt_set_key(cc, key); | |
28513fcc | 1242 | if (ret < 0) { |
0b430958 | 1243 | ti->error = "Error decoding and setting key"; |
28513fcc | 1244 | goto bad; |
0b430958 MB |
1245 | } |
1246 | ||
5ebaee6d | 1247 | /* Initialize IV */ |
c0297721 | 1248 | cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc)); |
5ebaee6d MB |
1249 | if (cc->iv_size) |
1250 | /* at least a 64 bit sector number should fit in our buffer */ | |
1251 | cc->iv_size = max(cc->iv_size, | |
1252 | (unsigned int)(sizeof(u64) / sizeof(u8))); | |
1253 | else if (ivmode) { | |
1254 | DMWARN("Selected cipher does not support IVs"); | |
1255 | ivmode = NULL; | |
1256 | } | |
1257 | ||
1258 | /* Choose ivmode, see comments at iv code. */ | |
1da177e4 LT |
1259 | if (ivmode == NULL) |
1260 | cc->iv_gen_ops = NULL; | |
1261 | else if (strcmp(ivmode, "plain") == 0) | |
1262 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
61afef61 MB |
1263 | else if (strcmp(ivmode, "plain64") == 0) |
1264 | cc->iv_gen_ops = &crypt_iv_plain64_ops; | |
1da177e4 LT |
1265 | else if (strcmp(ivmode, "essiv") == 0) |
1266 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
1267 | else if (strcmp(ivmode, "benbi") == 0) |
1268 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
1269 | else if (strcmp(ivmode, "null") == 0) |
1270 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 1271 | else { |
5ebaee6d | 1272 | ret = -EINVAL; |
72d94861 | 1273 | ti->error = "Invalid IV mode"; |
28513fcc | 1274 | goto bad; |
1da177e4 LT |
1275 | } |
1276 | ||
28513fcc MB |
1277 | /* Allocate IV */ |
1278 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { | |
1279 | ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); | |
1280 | if (ret < 0) { | |
1281 | ti->error = "Error creating IV"; | |
1282 | goto bad; | |
1283 | } | |
1284 | } | |
1da177e4 | 1285 | |
28513fcc MB |
1286 | /* Initialize IV (set keys for ESSIV etc) */ |
1287 | if (cc->iv_gen_ops && cc->iv_gen_ops->init) { | |
1288 | ret = cc->iv_gen_ops->init(cc); | |
1289 | if (ret < 0) { | |
1290 | ti->error = "Error initialising IV"; | |
1291 | goto bad; | |
1292 | } | |
b95bf2d3 MB |
1293 | } |
1294 | ||
5ebaee6d MB |
1295 | ret = 0; |
1296 | bad: | |
1297 | kfree(cipher_api); | |
1298 | return ret; | |
1299 | ||
1300 | bad_mem: | |
1301 | ti->error = "Cannot allocate cipher strings"; | |
1302 | return -ENOMEM; | |
1303 | } | |
1304 | ||
1305 | /* | |
1306 | * Construct an encryption mapping: | |
1307 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
1308 | */ | |
1309 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
1310 | { | |
1311 | struct crypt_config *cc; | |
1312 | unsigned int key_size; | |
1313 | unsigned long long tmpll; | |
1314 | int ret; | |
1315 | ||
1316 | if (argc != 5) { | |
1317 | ti->error = "Not enough arguments"; | |
1318 | return -EINVAL; | |
1da177e4 LT |
1319 | } |
1320 | ||
5ebaee6d MB |
1321 | key_size = strlen(argv[1]) >> 1; |
1322 | ||
1323 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); | |
1324 | if (!cc) { | |
1325 | ti->error = "Cannot allocate encryption context"; | |
1326 | return -ENOMEM; | |
1327 | } | |
69a8cfcd | 1328 | cc->key_size = key_size; |
5ebaee6d MB |
1329 | |
1330 | ti->private = cc; | |
1331 | ret = crypt_ctr_cipher(ti, argv[0], argv[1]); | |
1332 | if (ret < 0) | |
1333 | goto bad; | |
1334 | ||
28513fcc | 1335 | ret = -ENOMEM; |
93d2341c | 1336 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 1337 | if (!cc->io_pool) { |
72d94861 | 1338 | ti->error = "Cannot allocate crypt io mempool"; |
28513fcc | 1339 | goto bad; |
1da177e4 LT |
1340 | } |
1341 | ||
ddd42edf | 1342 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
c0297721 | 1343 | cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc)); |
ddd42edf | 1344 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); |
c0297721 | 1345 | cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) & |
3a7f6c99 | 1346 | ~(crypto_tfm_ctx_alignment() - 1); |
ddd42edf MB |
1347 | |
1348 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
1349 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
1350 | if (!cc->req_pool) { | |
1351 | ti->error = "Cannot allocate crypt request mempool"; | |
28513fcc | 1352 | goto bad; |
ddd42edf | 1353 | } |
ddd42edf | 1354 | |
a19b27ce | 1355 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 1356 | if (!cc->page_pool) { |
72d94861 | 1357 | ti->error = "Cannot allocate page mempool"; |
28513fcc | 1358 | goto bad; |
1da177e4 LT |
1359 | } |
1360 | ||
bb799ca0 | 1361 | cc->bs = bioset_create(MIN_IOS, 0); |
6a24c718 MB |
1362 | if (!cc->bs) { |
1363 | ti->error = "Cannot allocate crypt bioset"; | |
28513fcc | 1364 | goto bad; |
6a24c718 MB |
1365 | } |
1366 | ||
28513fcc | 1367 | ret = -EINVAL; |
4ee218cd | 1368 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 1369 | ti->error = "Invalid iv_offset sector"; |
28513fcc | 1370 | goto bad; |
1da177e4 | 1371 | } |
4ee218cd | 1372 | cc->iv_offset = tmpll; |
1da177e4 | 1373 | |
28513fcc MB |
1374 | if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) { |
1375 | ti->error = "Device lookup failed"; | |
1376 | goto bad; | |
1377 | } | |
1378 | ||
4ee218cd | 1379 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1380 | ti->error = "Invalid device sector"; |
28513fcc | 1381 | goto bad; |
1da177e4 | 1382 | } |
4ee218cd | 1383 | cc->start = tmpll; |
1da177e4 | 1384 | |
28513fcc | 1385 | ret = -ENOMEM; |
c0297721 AK |
1386 | cc->io_queue = alloc_workqueue("kcryptd_io", |
1387 | WQ_NON_REENTRANT| | |
1388 | WQ_MEM_RECLAIM, | |
1389 | 1); | |
cabf08e4 MB |
1390 | if (!cc->io_queue) { |
1391 | ti->error = "Couldn't create kcryptd io queue"; | |
28513fcc | 1392 | goto bad; |
cabf08e4 MB |
1393 | } |
1394 | ||
c0297721 AK |
1395 | cc->crypt_queue = alloc_workqueue("kcryptd", |
1396 | WQ_NON_REENTRANT| | |
1397 | WQ_CPU_INTENSIVE| | |
1398 | WQ_MEM_RECLAIM, | |
1399 | 1); | |
cabf08e4 | 1400 | if (!cc->crypt_queue) { |
9934a8be | 1401 | ti->error = "Couldn't create kcryptd queue"; |
28513fcc | 1402 | goto bad; |
9934a8be MB |
1403 | } |
1404 | ||
647c7db1 | 1405 | ti->num_flush_requests = 1; |
1da177e4 LT |
1406 | return 0; |
1407 | ||
28513fcc MB |
1408 | bad: |
1409 | crypt_dtr(ti); | |
1410 | return ret; | |
1da177e4 LT |
1411 | } |
1412 | ||
1da177e4 LT |
1413 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1414 | union map_info *map_context) | |
1415 | { | |
028867ac | 1416 | struct dm_crypt_io *io; |
647c7db1 MP |
1417 | struct crypt_config *cc; |
1418 | ||
d87f4c14 | 1419 | if (bio->bi_rw & REQ_FLUSH) { |
647c7db1 MP |
1420 | cc = ti->private; |
1421 | bio->bi_bdev = cc->dev->bdev; | |
1422 | return DM_MAPIO_REMAPPED; | |
1423 | } | |
1da177e4 | 1424 | |
b441a262 | 1425 | io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector)); |
cabf08e4 MB |
1426 | |
1427 | if (bio_data_dir(io->base_bio) == READ) | |
1428 | kcryptd_queue_io(io); | |
1429 | else | |
1430 | kcryptd_queue_crypt(io); | |
1da177e4 | 1431 | |
d2a7ad29 | 1432 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1433 | } |
1434 | ||
1435 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1436 | char *result, unsigned int maxlen) | |
1437 | { | |
5ebaee6d | 1438 | struct crypt_config *cc = ti->private; |
1da177e4 LT |
1439 | unsigned int sz = 0; |
1440 | ||
1441 | switch (type) { | |
1442 | case STATUSTYPE_INFO: | |
1443 | result[0] = '\0'; | |
1444 | break; | |
1445 | ||
1446 | case STATUSTYPE_TABLE: | |
7dbcd137 | 1447 | DMEMIT("%s ", cc->cipher_string); |
1da177e4 LT |
1448 | |
1449 | if (cc->key_size > 0) { | |
1450 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1451 | return -ENOMEM; | |
1452 | ||
1453 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1454 | sz += cc->key_size << 1; | |
1455 | } else { | |
1456 | if (sz >= maxlen) | |
1457 | return -ENOMEM; | |
1458 | result[sz++] = '-'; | |
1459 | } | |
1460 | ||
4ee218cd AM |
1461 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1462 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1463 | break; |
1464 | } | |
1465 | return 0; | |
1466 | } | |
1467 | ||
e48d4bbf MB |
1468 | static void crypt_postsuspend(struct dm_target *ti) |
1469 | { | |
1470 | struct crypt_config *cc = ti->private; | |
1471 | ||
1472 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1473 | } | |
1474 | ||
1475 | static int crypt_preresume(struct dm_target *ti) | |
1476 | { | |
1477 | struct crypt_config *cc = ti->private; | |
1478 | ||
1479 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1480 | DMERR("aborting resume - crypt key is not set."); | |
1481 | return -EAGAIN; | |
1482 | } | |
1483 | ||
1484 | return 0; | |
1485 | } | |
1486 | ||
1487 | static void crypt_resume(struct dm_target *ti) | |
1488 | { | |
1489 | struct crypt_config *cc = ti->private; | |
1490 | ||
1491 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1492 | } | |
1493 | ||
1494 | /* Message interface | |
1495 | * key set <key> | |
1496 | * key wipe | |
1497 | */ | |
1498 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1499 | { | |
1500 | struct crypt_config *cc = ti->private; | |
542da317 | 1501 | int ret = -EINVAL; |
e48d4bbf MB |
1502 | |
1503 | if (argc < 2) | |
1504 | goto error; | |
1505 | ||
1506 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1507 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1508 | DMWARN("not suspended during key manipulation."); | |
1509 | return -EINVAL; | |
1510 | } | |
542da317 MB |
1511 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) { |
1512 | ret = crypt_set_key(cc, argv[2]); | |
1513 | if (ret) | |
1514 | return ret; | |
1515 | if (cc->iv_gen_ops && cc->iv_gen_ops->init) | |
1516 | ret = cc->iv_gen_ops->init(cc); | |
1517 | return ret; | |
1518 | } | |
1519 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) { | |
1520 | if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { | |
1521 | ret = cc->iv_gen_ops->wipe(cc); | |
1522 | if (ret) | |
1523 | return ret; | |
1524 | } | |
e48d4bbf | 1525 | return crypt_wipe_key(cc); |
542da317 | 1526 | } |
e48d4bbf MB |
1527 | } |
1528 | ||
1529 | error: | |
1530 | DMWARN("unrecognised message received."); | |
1531 | return -EINVAL; | |
1532 | } | |
1533 | ||
d41e26b9 MB |
1534 | static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
1535 | struct bio_vec *biovec, int max_size) | |
1536 | { | |
1537 | struct crypt_config *cc = ti->private; | |
1538 | struct request_queue *q = bdev_get_queue(cc->dev->bdev); | |
1539 | ||
1540 | if (!q->merge_bvec_fn) | |
1541 | return max_size; | |
1542 | ||
1543 | bvm->bi_bdev = cc->dev->bdev; | |
b441a262 | 1544 | bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector); |
d41e26b9 MB |
1545 | |
1546 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); | |
1547 | } | |
1548 | ||
af4874e0 MS |
1549 | static int crypt_iterate_devices(struct dm_target *ti, |
1550 | iterate_devices_callout_fn fn, void *data) | |
1551 | { | |
1552 | struct crypt_config *cc = ti->private; | |
1553 | ||
5dea271b | 1554 | return fn(ti, cc->dev, cc->start, ti->len, data); |
af4874e0 MS |
1555 | } |
1556 | ||
1da177e4 LT |
1557 | static struct target_type crypt_target = { |
1558 | .name = "crypt", | |
c0297721 | 1559 | .version = {1, 9, 0}, |
1da177e4 LT |
1560 | .module = THIS_MODULE, |
1561 | .ctr = crypt_ctr, | |
1562 | .dtr = crypt_dtr, | |
1563 | .map = crypt_map, | |
1564 | .status = crypt_status, | |
e48d4bbf MB |
1565 | .postsuspend = crypt_postsuspend, |
1566 | .preresume = crypt_preresume, | |
1567 | .resume = crypt_resume, | |
1568 | .message = crypt_message, | |
d41e26b9 | 1569 | .merge = crypt_merge, |
af4874e0 | 1570 | .iterate_devices = crypt_iterate_devices, |
1da177e4 LT |
1571 | }; |
1572 | ||
1573 | static int __init dm_crypt_init(void) | |
1574 | { | |
1575 | int r; | |
1576 | ||
028867ac | 1577 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1578 | if (!_crypt_io_pool) |
1579 | return -ENOMEM; | |
1580 | ||
1da177e4 LT |
1581 | r = dm_register_target(&crypt_target); |
1582 | if (r < 0) { | |
72d94861 | 1583 | DMERR("register failed %d", r); |
9934a8be | 1584 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1585 | } |
1586 | ||
1da177e4 LT |
1587 | return r; |
1588 | } | |
1589 | ||
1590 | static void __exit dm_crypt_exit(void) | |
1591 | { | |
10d3bd09 | 1592 | dm_unregister_target(&crypt_target); |
1da177e4 LT |
1593 | kmem_cache_destroy(_crypt_io_pool); |
1594 | } | |
1595 | ||
1596 | module_init(dm_crypt_init); | |
1597 | module_exit(dm_crypt_exit); | |
1598 | ||
1599 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1600 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1601 | MODULE_LICENSE("GPL"); |