Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
3f1e9070 | 4 | * Copyright (C) 2006-2008 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> |
1da177e4 | 21 | #include <asm/atomic.h> |
378f058c | 22 | #include <linux/scatterlist.h> |
1da177e4 | 23 | #include <asm/page.h> |
48527fa7 | 24 | #include <asm/unaligned.h> |
1da177e4 LT |
25 | |
26 | #include "dm.h" | |
27 | ||
72d94861 | 28 | #define DM_MSG_PREFIX "crypt" |
e48d4bbf | 29 | #define MESG_STR(x) x, sizeof(x) |
1da177e4 | 30 | |
1da177e4 LT |
31 | /* |
32 | * context holding the current state of a multi-part conversion | |
33 | */ | |
34 | struct convert_context { | |
43d69034 | 35 | struct completion restart; |
1da177e4 LT |
36 | struct bio *bio_in; |
37 | struct bio *bio_out; | |
38 | unsigned int offset_in; | |
39 | unsigned int offset_out; | |
40 | unsigned int idx_in; | |
41 | unsigned int idx_out; | |
42 | sector_t sector; | |
43d69034 | 43 | atomic_t pending; |
1da177e4 LT |
44 | }; |
45 | ||
53017030 MB |
46 | /* |
47 | * per bio private data | |
48 | */ | |
49 | struct dm_crypt_io { | |
50 | struct dm_target *target; | |
51 | struct bio *base_bio; | |
52 | struct work_struct work; | |
53 | ||
54 | struct convert_context ctx; | |
55 | ||
56 | atomic_t pending; | |
57 | int error; | |
0c395b0f | 58 | sector_t sector; |
53017030 MB |
59 | }; |
60 | ||
01482b76 MB |
61 | struct dm_crypt_request { |
62 | struct scatterlist sg_in; | |
63 | struct scatterlist sg_out; | |
64 | }; | |
65 | ||
1da177e4 LT |
66 | struct crypt_config; |
67 | ||
68 | struct crypt_iv_operations { | |
69 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 70 | const char *opts); |
1da177e4 LT |
71 | void (*dtr)(struct crypt_config *cc); |
72 | const char *(*status)(struct crypt_config *cc); | |
73 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
74 | }; | |
75 | ||
76 | /* | |
77 | * Crypt: maps a linear range of a block device | |
78 | * and encrypts / decrypts at the same time. | |
79 | */ | |
e48d4bbf | 80 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
81 | struct crypt_config { |
82 | struct dm_dev *dev; | |
83 | sector_t start; | |
84 | ||
85 | /* | |
ddd42edf MB |
86 | * pool for per bio private data, crypto requests and |
87 | * encryption requeusts/buffer pages | |
1da177e4 LT |
88 | */ |
89 | mempool_t *io_pool; | |
ddd42edf | 90 | mempool_t *req_pool; |
1da177e4 | 91 | mempool_t *page_pool; |
6a24c718 | 92 | struct bio_set *bs; |
1da177e4 | 93 | |
cabf08e4 MB |
94 | struct workqueue_struct *io_queue; |
95 | struct workqueue_struct *crypt_queue; | |
3f1e9070 MB |
96 | wait_queue_head_t writeq; |
97 | ||
1da177e4 LT |
98 | /* |
99 | * crypto related data | |
100 | */ | |
101 | struct crypt_iv_operations *iv_gen_ops; | |
102 | char *iv_mode; | |
79066ad3 HX |
103 | union { |
104 | struct crypto_cipher *essiv_tfm; | |
105 | int benbi_shift; | |
106 | } iv_gen_private; | |
1da177e4 LT |
107 | sector_t iv_offset; |
108 | unsigned int iv_size; | |
109 | ||
ddd42edf MB |
110 | /* |
111 | * Layout of each crypto request: | |
112 | * | |
113 | * struct ablkcipher_request | |
114 | * context | |
115 | * padding | |
116 | * struct dm_crypt_request | |
117 | * padding | |
118 | * IV | |
119 | * | |
120 | * The padding is added so that dm_crypt_request and the IV are | |
121 | * correctly aligned. | |
122 | */ | |
123 | unsigned int dmreq_start; | |
124 | struct ablkcipher_request *req; | |
125 | ||
d1806f6a HX |
126 | char cipher[CRYPTO_MAX_ALG_NAME]; |
127 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
3a7f6c99 | 128 | struct crypto_ablkcipher *tfm; |
e48d4bbf | 129 | unsigned long flags; |
1da177e4 LT |
130 | unsigned int key_size; |
131 | u8 key[0]; | |
132 | }; | |
133 | ||
6a24c718 | 134 | #define MIN_IOS 16 |
1da177e4 LT |
135 | #define MIN_POOL_PAGES 32 |
136 | #define MIN_BIO_PAGES 8 | |
137 | ||
e18b890b | 138 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 139 | |
028867ac | 140 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 141 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 142 | |
1da177e4 LT |
143 | /* |
144 | * Different IV generation algorithms: | |
145 | * | |
3c164bd8 | 146 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 147 | * number, padded with zeros if necessary. |
1da177e4 | 148 | * |
3c164bd8 RS |
149 | * essiv: "encrypted sector|salt initial vector", the sector number is |
150 | * encrypted with the bulk cipher using a salt as key. The salt | |
151 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 152 | * |
48527fa7 RS |
153 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
154 | * (needed for LRW-32-AES and possible other narrow block modes) | |
155 | * | |
46b47730 LN |
156 | * null: the initial vector is always zero. Provides compatibility with |
157 | * obsolete loop_fish2 devices. Do not use for new devices. | |
158 | * | |
1da177e4 LT |
159 | * plumb: unimplemented, see: |
160 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
161 | */ | |
162 | ||
163 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
164 | { | |
165 | memset(iv, 0, cc->iv_size); | |
166 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
167 | ||
168 | return 0; | |
169 | } | |
170 | ||
171 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 172 | const char *opts) |
1da177e4 | 173 | { |
d1806f6a | 174 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
175 | struct crypto_hash *hash_tfm; |
176 | struct hash_desc desc; | |
1da177e4 LT |
177 | struct scatterlist sg; |
178 | unsigned int saltsize; | |
179 | u8 *salt; | |
d1806f6a | 180 | int err; |
1da177e4 LT |
181 | |
182 | if (opts == NULL) { | |
72d94861 | 183 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
184 | return -EINVAL; |
185 | } | |
186 | ||
187 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
188 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
189 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 190 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 191 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
192 | } |
193 | ||
35058687 | 194 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
195 | salt = kmalloc(saltsize, GFP_KERNEL); |
196 | if (salt == NULL) { | |
72d94861 | 197 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 198 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
199 | return -ENOMEM; |
200 | } | |
201 | ||
68e3f5dd | 202 | sg_init_one(&sg, cc->key, cc->key_size); |
35058687 HX |
203 | desc.tfm = hash_tfm; |
204 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
205 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
206 | crypto_free_hash(hash_tfm); | |
207 | ||
208 | if (err) { | |
209 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 210 | kfree(salt); |
35058687 HX |
211 | return err; |
212 | } | |
1da177e4 LT |
213 | |
214 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
215 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
216 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 217 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 218 | kfree(salt); |
d1806f6a | 219 | return PTR_ERR(essiv_tfm); |
1da177e4 | 220 | } |
d1806f6a | 221 | if (crypto_cipher_blocksize(essiv_tfm) != |
3a7f6c99 | 222 | crypto_ablkcipher_ivsize(cc->tfm)) { |
72d94861 | 223 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 224 | "not match IV size of block cipher"; |
d1806f6a | 225 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
226 | kfree(salt); |
227 | return -EINVAL; | |
228 | } | |
d1806f6a HX |
229 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
230 | if (err) { | |
72d94861 | 231 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 232 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 233 | kfree(salt); |
d1806f6a | 234 | return err; |
1da177e4 LT |
235 | } |
236 | kfree(salt); | |
237 | ||
79066ad3 | 238 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
239 | return 0; |
240 | } | |
241 | ||
242 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
243 | { | |
79066ad3 HX |
244 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
245 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
246 | } |
247 | ||
248 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
249 | { | |
1da177e4 LT |
250 | memset(iv, 0, cc->iv_size); |
251 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 252 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
253 | return 0; |
254 | } | |
255 | ||
48527fa7 RS |
256 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
257 | const char *opts) | |
258 | { | |
3a7f6c99 | 259 | unsigned bs = crypto_ablkcipher_blocksize(cc->tfm); |
f0d1b0b3 | 260 | int log = ilog2(bs); |
48527fa7 RS |
261 | |
262 | /* we need to calculate how far we must shift the sector count | |
263 | * to get the cipher block count, we use this shift in _gen */ | |
264 | ||
265 | if (1 << log != bs) { | |
266 | ti->error = "cypher blocksize is not a power of 2"; | |
267 | return -EINVAL; | |
268 | } | |
269 | ||
270 | if (log > 9) { | |
271 | ti->error = "cypher blocksize is > 512"; | |
272 | return -EINVAL; | |
273 | } | |
274 | ||
79066ad3 | 275 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
276 | |
277 | return 0; | |
278 | } | |
279 | ||
280 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
281 | { | |
48527fa7 RS |
282 | } |
283 | ||
284 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
285 | { | |
79066ad3 HX |
286 | __be64 val; |
287 | ||
48527fa7 | 288 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
289 | |
290 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
291 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 292 | |
1da177e4 LT |
293 | return 0; |
294 | } | |
295 | ||
46b47730 LN |
296 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
297 | { | |
298 | memset(iv, 0, cc->iv_size); | |
299 | ||
300 | return 0; | |
301 | } | |
302 | ||
1da177e4 LT |
303 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
304 | .generator = crypt_iv_plain_gen | |
305 | }; | |
306 | ||
307 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
308 | .ctr = crypt_iv_essiv_ctr, | |
309 | .dtr = crypt_iv_essiv_dtr, | |
310 | .generator = crypt_iv_essiv_gen | |
311 | }; | |
312 | ||
48527fa7 RS |
313 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
314 | .ctr = crypt_iv_benbi_ctr, | |
315 | .dtr = crypt_iv_benbi_dtr, | |
316 | .generator = crypt_iv_benbi_gen | |
317 | }; | |
1da177e4 | 318 | |
46b47730 LN |
319 | static struct crypt_iv_operations crypt_iv_null_ops = { |
320 | .generator = crypt_iv_null_gen | |
321 | }; | |
322 | ||
d469f841 MB |
323 | static void crypt_convert_init(struct crypt_config *cc, |
324 | struct convert_context *ctx, | |
325 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 326 | sector_t sector) |
1da177e4 LT |
327 | { |
328 | ctx->bio_in = bio_in; | |
329 | ctx->bio_out = bio_out; | |
330 | ctx->offset_in = 0; | |
331 | ctx->offset_out = 0; | |
332 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
333 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
334 | ctx->sector = sector + cc->iv_offset; | |
43d69034 | 335 | init_completion(&ctx->restart); |
3f1e9070 | 336 | atomic_set(&ctx->pending, 1); |
1da177e4 LT |
337 | } |
338 | ||
01482b76 | 339 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
340 | struct convert_context *ctx, |
341 | struct ablkcipher_request *req) | |
01482b76 MB |
342 | { |
343 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
344 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
3a7f6c99 MB |
345 | struct dm_crypt_request *dmreq; |
346 | u8 *iv; | |
347 | int r = 0; | |
348 | ||
349 | dmreq = (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
350 | iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), | |
351 | crypto_ablkcipher_alignmask(cc->tfm) + 1); | |
01482b76 | 352 | |
3a7f6c99 MB |
353 | sg_init_table(&dmreq->sg_in, 1); |
354 | sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
355 | bv_in->bv_offset + ctx->offset_in); |
356 | ||
3a7f6c99 MB |
357 | sg_init_table(&dmreq->sg_out, 1); |
358 | sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
359 | bv_out->bv_offset + ctx->offset_out); |
360 | ||
361 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
362 | if (ctx->offset_in >= bv_in->bv_len) { | |
363 | ctx->offset_in = 0; | |
364 | ctx->idx_in++; | |
365 | } | |
366 | ||
367 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
368 | if (ctx->offset_out >= bv_out->bv_len) { | |
369 | ctx->offset_out = 0; | |
370 | ctx->idx_out++; | |
371 | } | |
372 | ||
3a7f6c99 MB |
373 | if (cc->iv_gen_ops) { |
374 | r = cc->iv_gen_ops->generator(cc, iv, ctx->sector); | |
375 | if (r < 0) | |
376 | return r; | |
377 | } | |
378 | ||
379 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
380 | 1 << SECTOR_SHIFT, iv); | |
381 | ||
382 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
383 | r = crypto_ablkcipher_encrypt(req); | |
384 | else | |
385 | r = crypto_ablkcipher_decrypt(req); | |
386 | ||
387 | return r; | |
01482b76 MB |
388 | } |
389 | ||
95497a96 MB |
390 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
391 | int error); | |
ddd42edf MB |
392 | static void crypt_alloc_req(struct crypt_config *cc, |
393 | struct convert_context *ctx) | |
394 | { | |
395 | if (!cc->req) | |
396 | cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
95497a96 MB |
397 | ablkcipher_request_set_tfm(cc->req, cc->tfm); |
398 | ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | | |
399 | CRYPTO_TFM_REQ_MAY_SLEEP, | |
400 | kcryptd_async_done, ctx); | |
ddd42edf MB |
401 | } |
402 | ||
1da177e4 LT |
403 | /* |
404 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
405 | */ | |
406 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 407 | struct convert_context *ctx) |
1da177e4 | 408 | { |
3f1e9070 | 409 | int r; |
1da177e4 LT |
410 | |
411 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
412 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
1da177e4 | 413 | |
3a7f6c99 MB |
414 | crypt_alloc_req(cc, ctx); |
415 | ||
3f1e9070 MB |
416 | atomic_inc(&ctx->pending); |
417 | ||
3a7f6c99 MB |
418 | r = crypt_convert_block(cc, ctx, cc->req); |
419 | ||
420 | switch (r) { | |
3f1e9070 | 421 | /* async */ |
3a7f6c99 MB |
422 | case -EBUSY: |
423 | wait_for_completion(&ctx->restart); | |
424 | INIT_COMPLETION(ctx->restart); | |
425 | /* fall through*/ | |
426 | case -EINPROGRESS: | |
3a7f6c99 | 427 | cc->req = NULL; |
3f1e9070 MB |
428 | ctx->sector++; |
429 | continue; | |
430 | ||
431 | /* sync */ | |
3a7f6c99 | 432 | case 0: |
3f1e9070 | 433 | atomic_dec(&ctx->pending); |
3a7f6c99 | 434 | ctx->sector++; |
c7f1b204 | 435 | cond_resched(); |
3a7f6c99 | 436 | continue; |
3a7f6c99 | 437 | |
3f1e9070 MB |
438 | /* error */ |
439 | default: | |
440 | atomic_dec(&ctx->pending); | |
441 | return r; | |
442 | } | |
1da177e4 LT |
443 | } |
444 | ||
3f1e9070 | 445 | return 0; |
1da177e4 LT |
446 | } |
447 | ||
d469f841 MB |
448 | static void dm_crypt_bio_destructor(struct bio *bio) |
449 | { | |
028867ac | 450 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
451 | struct crypt_config *cc = io->target->private; |
452 | ||
453 | bio_free(bio, cc->bs); | |
d469f841 | 454 | } |
6a24c718 | 455 | |
1da177e4 LT |
456 | /* |
457 | * Generate a new unfragmented bio with the given size | |
458 | * This should never violate the device limitations | |
459 | * May return a smaller bio when running out of pages | |
460 | */ | |
028867ac | 461 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 462 | { |
027581f3 | 463 | struct crypt_config *cc = io->target->private; |
8b004457 | 464 | struct bio *clone; |
1da177e4 | 465 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 466 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
467 | unsigned i, len; |
468 | struct page *page; | |
1da177e4 | 469 | |
2f9941b6 | 470 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 471 | if (!clone) |
1da177e4 | 472 | return NULL; |
1da177e4 | 473 | |
027581f3 | 474 | clone_init(io, clone); |
6a24c718 | 475 | |
f97380bc | 476 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
477 | page = mempool_alloc(cc->page_pool, gfp_mask); |
478 | if (!page) | |
1da177e4 LT |
479 | break; |
480 | ||
481 | /* | |
482 | * if additional pages cannot be allocated without waiting, | |
483 | * return a partially allocated bio, the caller will then try | |
484 | * to allocate additional bios while submitting this partial bio | |
485 | */ | |
f97380bc | 486 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
487 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
488 | ||
91e10625 MB |
489 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
490 | ||
491 | if (!bio_add_page(clone, page, len, 0)) { | |
492 | mempool_free(page, cc->page_pool); | |
493 | break; | |
494 | } | |
1da177e4 | 495 | |
91e10625 | 496 | size -= len; |
1da177e4 LT |
497 | } |
498 | ||
8b004457 MB |
499 | if (!clone->bi_size) { |
500 | bio_put(clone); | |
1da177e4 LT |
501 | return NULL; |
502 | } | |
503 | ||
8b004457 | 504 | return clone; |
1da177e4 LT |
505 | } |
506 | ||
644bd2f0 | 507 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 508 | { |
644bd2f0 | 509 | unsigned int i; |
1da177e4 LT |
510 | struct bio_vec *bv; |
511 | ||
644bd2f0 | 512 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 513 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
514 | BUG_ON(!bv->bv_page); |
515 | mempool_free(bv->bv_page, cc->page_pool); | |
516 | bv->bv_page = NULL; | |
517 | } | |
518 | } | |
519 | ||
dc440d1e MB |
520 | static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti, |
521 | struct bio *bio, sector_t sector) | |
522 | { | |
523 | struct crypt_config *cc = ti->private; | |
524 | struct dm_crypt_io *io; | |
525 | ||
526 | io = mempool_alloc(cc->io_pool, GFP_NOIO); | |
527 | io->target = ti; | |
528 | io->base_bio = bio; | |
529 | io->sector = sector; | |
530 | io->error = 0; | |
531 | atomic_set(&io->pending, 0); | |
532 | ||
533 | return io; | |
534 | } | |
535 | ||
3e1a8bdd MB |
536 | static void crypt_inc_pending(struct dm_crypt_io *io) |
537 | { | |
538 | atomic_inc(&io->pending); | |
539 | } | |
540 | ||
1da177e4 LT |
541 | /* |
542 | * One of the bios was finished. Check for completion of | |
543 | * the whole request and correctly clean up the buffer. | |
544 | */ | |
5742fd77 | 545 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 546 | { |
5742fd77 | 547 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
548 | |
549 | if (!atomic_dec_and_test(&io->pending)) | |
550 | return; | |
551 | ||
6712ecf8 | 552 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
553 | mempool_free(io, cc->io_pool); |
554 | } | |
555 | ||
556 | /* | |
cabf08e4 | 557 | * kcryptd/kcryptd_io: |
1da177e4 LT |
558 | * |
559 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 560 | * interrupt context. |
cabf08e4 MB |
561 | * |
562 | * kcryptd performs the actual encryption or decryption. | |
563 | * | |
564 | * kcryptd_io performs the IO submission. | |
565 | * | |
566 | * They must be separated as otherwise the final stages could be | |
567 | * starved by new requests which can block in the first stages due | |
568 | * to memory allocation. | |
1da177e4 | 569 | */ |
6712ecf8 | 570 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 571 | { |
028867ac | 572 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 573 | struct crypt_config *cc = io->target->private; |
ee7a491e | 574 | unsigned rw = bio_data_dir(clone); |
8b004457 | 575 | |
adfe4770 MB |
576 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
577 | error = -EIO; | |
578 | ||
8b004457 | 579 | /* |
6712ecf8 | 580 | * free the processed pages |
8b004457 | 581 | */ |
ee7a491e | 582 | if (rw == WRITE) |
644bd2f0 | 583 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
584 | |
585 | bio_put(clone); | |
8b004457 | 586 | |
ee7a491e MB |
587 | if (rw == READ && !error) { |
588 | kcryptd_queue_crypt(io); | |
589 | return; | |
590 | } | |
5742fd77 MB |
591 | |
592 | if (unlikely(error)) | |
593 | io->error = error; | |
594 | ||
595 | crypt_dec_pending(io); | |
8b004457 MB |
596 | } |
597 | ||
028867ac | 598 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
599 | { |
600 | struct crypt_config *cc = io->target->private; | |
601 | ||
602 | clone->bi_private = io; | |
603 | clone->bi_end_io = crypt_endio; | |
604 | clone->bi_bdev = cc->dev->bdev; | |
605 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 606 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
607 | } |
608 | ||
4e4eef64 | 609 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
610 | { |
611 | struct crypt_config *cc = io->target->private; | |
612 | struct bio *base_bio = io->base_bio; | |
613 | struct bio *clone; | |
93e605c2 | 614 | |
3e1a8bdd | 615 | crypt_inc_pending(io); |
8b004457 MB |
616 | |
617 | /* | |
618 | * The block layer might modify the bvec array, so always | |
619 | * copy the required bvecs because we need the original | |
620 | * one in order to decrypt the whole bio data *afterwards*. | |
621 | */ | |
6a24c718 | 622 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 623 | if (unlikely(!clone)) { |
5742fd77 MB |
624 | io->error = -ENOMEM; |
625 | crypt_dec_pending(io); | |
23541d2d | 626 | return; |
93e605c2 | 627 | } |
8b004457 MB |
628 | |
629 | clone_init(io, clone); | |
630 | clone->bi_idx = 0; | |
631 | clone->bi_vcnt = bio_segments(base_bio); | |
632 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 633 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
634 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
635 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 636 | |
93e605c2 | 637 | generic_make_request(clone); |
8b004457 MB |
638 | } |
639 | ||
4e4eef64 MB |
640 | static void kcryptd_io_write(struct dm_crypt_io *io) |
641 | { | |
95497a96 | 642 | struct bio *clone = io->ctx.bio_out; |
3f1e9070 | 643 | struct crypt_config *cc = io->target->private; |
95497a96 MB |
644 | |
645 | generic_make_request(clone); | |
3f1e9070 | 646 | wake_up(&cc->writeq); |
4e4eef64 MB |
647 | } |
648 | ||
395b167c AK |
649 | static void kcryptd_io(struct work_struct *work) |
650 | { | |
651 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
652 | ||
653 | if (bio_data_dir(io->base_bio) == READ) | |
654 | kcryptd_io_read(io); | |
655 | else | |
656 | kcryptd_io_write(io); | |
657 | } | |
658 | ||
659 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
660 | { | |
661 | struct crypt_config *cc = io->target->private; | |
662 | ||
663 | INIT_WORK(&io->work, kcryptd_io); | |
664 | queue_work(cc->io_queue, &io->work); | |
665 | } | |
666 | ||
95497a96 MB |
667 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
668 | int error, int async) | |
4e4eef64 | 669 | { |
dec1cedf MB |
670 | struct bio *clone = io->ctx.bio_out; |
671 | struct crypt_config *cc = io->target->private; | |
672 | ||
673 | if (unlikely(error < 0)) { | |
674 | crypt_free_buffer_pages(cc, clone); | |
675 | bio_put(clone); | |
676 | io->error = -EIO; | |
6c031f41 | 677 | crypt_dec_pending(io); |
dec1cedf MB |
678 | return; |
679 | } | |
680 | ||
681 | /* crypt_convert should have filled the clone bio */ | |
682 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
683 | ||
684 | clone->bi_sector = cc->start + io->sector; | |
685 | io->sector += bio_sectors(clone); | |
899c95d3 | 686 | |
95497a96 MB |
687 | if (async) |
688 | kcryptd_queue_io(io); | |
1e37bb8e | 689 | else |
95497a96 | 690 | generic_make_request(clone); |
4e4eef64 MB |
691 | } |
692 | ||
fc5a5e9a | 693 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
8b004457 MB |
694 | { |
695 | struct crypt_config *cc = io->target->private; | |
8b004457 | 696 | struct bio *clone; |
dec1cedf MB |
697 | unsigned remaining = io->base_bio->bi_size; |
698 | int r; | |
8b004457 | 699 | |
fc5a5e9a MB |
700 | /* |
701 | * Prevent io from disappearing until this function completes. | |
702 | */ | |
703 | crypt_inc_pending(io); | |
704 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector); | |
705 | ||
93e605c2 MB |
706 | /* |
707 | * The allocated buffers can be smaller than the whole bio, | |
708 | * so repeat the whole process until all the data can be handled. | |
709 | */ | |
710 | while (remaining) { | |
f97380bc | 711 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 712 | if (unlikely(!clone)) { |
5742fd77 | 713 | io->error = -ENOMEM; |
fc5a5e9a | 714 | break; |
23541d2d | 715 | } |
93e605c2 | 716 | |
53017030 MB |
717 | io->ctx.bio_out = clone; |
718 | io->ctx.idx_out = 0; | |
93e605c2 | 719 | |
dec1cedf | 720 | remaining -= clone->bi_size; |
93e605c2 | 721 | |
4e594098 | 722 | crypt_inc_pending(io); |
dec1cedf | 723 | r = crypt_convert(cc, &io->ctx); |
f97380bc | 724 | |
3f1e9070 MB |
725 | if (atomic_dec_and_test(&io->ctx.pending)) { |
726 | /* processed, no running async crypto */ | |
3a7f6c99 | 727 | kcryptd_crypt_write_io_submit(io, r, 0); |
6c031f41 | 728 | if (unlikely(r < 0)) |
fc5a5e9a | 729 | break; |
4e594098 | 730 | } |
93e605c2 | 731 | |
93e605c2 | 732 | /* out of memory -> run queues */ |
3f1e9070 MB |
733 | if (unlikely(remaining)) { |
734 | /* wait for async crypto then reinitialize pending */ | |
735 | wait_event(cc->writeq, !atomic_read(&io->ctx.pending)); | |
736 | atomic_set(&io->ctx.pending, 1); | |
98221eb7 | 737 | congestion_wait(WRITE, HZ/100); |
3f1e9070 | 738 | } |
93e605c2 | 739 | } |
899c95d3 MB |
740 | |
741 | crypt_dec_pending(io); | |
84131db6 MB |
742 | } |
743 | ||
4e4eef64 | 744 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
745 | { |
746 | if (unlikely(error < 0)) | |
747 | io->error = -EIO; | |
748 | ||
749 | crypt_dec_pending(io); | |
750 | } | |
751 | ||
4e4eef64 | 752 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
753 | { |
754 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 755 | int r = 0; |
1da177e4 | 756 | |
3e1a8bdd | 757 | crypt_inc_pending(io); |
3a7f6c99 | 758 | |
53017030 | 759 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 760 | io->sector); |
1da177e4 | 761 | |
5742fd77 MB |
762 | r = crypt_convert(cc, &io->ctx); |
763 | ||
3f1e9070 | 764 | if (atomic_dec_and_test(&io->ctx.pending)) |
3a7f6c99 MB |
765 | kcryptd_crypt_read_done(io, r); |
766 | ||
767 | crypt_dec_pending(io); | |
1da177e4 LT |
768 | } |
769 | ||
95497a96 MB |
770 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
771 | int error) | |
772 | { | |
773 | struct convert_context *ctx = async_req->data; | |
774 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); | |
775 | struct crypt_config *cc = io->target->private; | |
776 | ||
777 | if (error == -EINPROGRESS) { | |
778 | complete(&ctx->restart); | |
779 | return; | |
780 | } | |
781 | ||
782 | mempool_free(ablkcipher_request_cast(async_req), cc->req_pool); | |
783 | ||
784 | if (!atomic_dec_and_test(&ctx->pending)) | |
785 | return; | |
786 | ||
787 | if (bio_data_dir(io->base_bio) == READ) | |
788 | kcryptd_crypt_read_done(io, error); | |
789 | else | |
790 | kcryptd_crypt_write_io_submit(io, error, 1); | |
791 | } | |
792 | ||
395b167c | 793 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 794 | { |
028867ac | 795 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 796 | |
cabf08e4 | 797 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 798 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 799 | else |
395b167c | 800 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
801 | } |
802 | ||
395b167c | 803 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 804 | { |
395b167c | 805 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 806 | |
395b167c AK |
807 | INIT_WORK(&io->work, kcryptd_crypt); |
808 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
809 | } |
810 | ||
811 | /* | |
812 | * Decode key from its hex representation | |
813 | */ | |
814 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
815 | { | |
816 | char buffer[3]; | |
817 | char *endp; | |
818 | unsigned int i; | |
819 | ||
820 | buffer[2] = '\0'; | |
821 | ||
8b004457 | 822 | for (i = 0; i < size; i++) { |
1da177e4 LT |
823 | buffer[0] = *hex++; |
824 | buffer[1] = *hex++; | |
825 | ||
826 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
827 | ||
828 | if (endp != &buffer[2]) | |
829 | return -EINVAL; | |
830 | } | |
831 | ||
832 | if (*hex != '\0') | |
833 | return -EINVAL; | |
834 | ||
835 | return 0; | |
836 | } | |
837 | ||
838 | /* | |
839 | * Encode key into its hex representation | |
840 | */ | |
841 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
842 | { | |
843 | unsigned int i; | |
844 | ||
8b004457 | 845 | for (i = 0; i < size; i++) { |
1da177e4 LT |
846 | sprintf(hex, "%02x", *key); |
847 | hex += 2; | |
848 | key++; | |
849 | } | |
850 | } | |
851 | ||
e48d4bbf MB |
852 | static int crypt_set_key(struct crypt_config *cc, char *key) |
853 | { | |
854 | unsigned key_size = strlen(key) >> 1; | |
855 | ||
856 | if (cc->key_size && cc->key_size != key_size) | |
857 | return -EINVAL; | |
858 | ||
859 | cc->key_size = key_size; /* initial settings */ | |
860 | ||
861 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 862 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
863 | return -EINVAL; |
864 | ||
865 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
866 | ||
867 | return 0; | |
868 | } | |
869 | ||
870 | static int crypt_wipe_key(struct crypt_config *cc) | |
871 | { | |
872 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
873 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
874 | return 0; | |
875 | } | |
876 | ||
1da177e4 LT |
877 | /* |
878 | * Construct an encryption mapping: | |
879 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
880 | */ | |
881 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
882 | { | |
883 | struct crypt_config *cc; | |
3a7f6c99 | 884 | struct crypto_ablkcipher *tfm; |
1da177e4 LT |
885 | char *tmp; |
886 | char *cipher; | |
887 | char *chainmode; | |
888 | char *ivmode; | |
889 | char *ivopts; | |
1da177e4 | 890 | unsigned int key_size; |
4ee218cd | 891 | unsigned long long tmpll; |
1da177e4 LT |
892 | |
893 | if (argc != 5) { | |
72d94861 | 894 | ti->error = "Not enough arguments"; |
1da177e4 LT |
895 | return -EINVAL; |
896 | } | |
897 | ||
898 | tmp = argv[0]; | |
899 | cipher = strsep(&tmp, "-"); | |
900 | chainmode = strsep(&tmp, "-"); | |
901 | ivopts = strsep(&tmp, "-"); | |
902 | ivmode = strsep(&ivopts, ":"); | |
903 | ||
904 | if (tmp) | |
72d94861 | 905 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
906 | |
907 | key_size = strlen(argv[1]) >> 1; | |
908 | ||
e48d4bbf | 909 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
910 | if (cc == NULL) { |
911 | ti->error = | |
72d94861 | 912 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
913 | return -ENOMEM; |
914 | } | |
915 | ||
e48d4bbf | 916 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 917 | ti->error = "Error decoding key"; |
636d5786 | 918 | goto bad_cipher; |
1da177e4 LT |
919 | } |
920 | ||
921 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
922 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
923 | chainmode = "cbc"; | |
924 | ivmode = "plain"; | |
925 | } | |
926 | ||
d1806f6a HX |
927 | if (strcmp(chainmode, "ecb") && !ivmode) { |
928 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 929 | goto bad_cipher; |
1da177e4 LT |
930 | } |
931 | ||
d469f841 MB |
932 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
933 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 934 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 935 | goto bad_cipher; |
1da177e4 LT |
936 | } |
937 | ||
3a7f6c99 | 938 | tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0); |
d1806f6a | 939 | if (IS_ERR(tfm)) { |
72d94861 | 940 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 941 | goto bad_cipher; |
1da177e4 | 942 | } |
1da177e4 | 943 | |
d1806f6a HX |
944 | strcpy(cc->cipher, cipher); |
945 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
946 | cc->tfm = tfm; |
947 | ||
948 | /* | |
48527fa7 | 949 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
950 | * See comments at iv code |
951 | */ | |
952 | ||
953 | if (ivmode == NULL) | |
954 | cc->iv_gen_ops = NULL; | |
955 | else if (strcmp(ivmode, "plain") == 0) | |
956 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
957 | else if (strcmp(ivmode, "essiv") == 0) | |
958 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
959 | else if (strcmp(ivmode, "benbi") == 0) |
960 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
961 | else if (strcmp(ivmode, "null") == 0) |
962 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 963 | else { |
72d94861 | 964 | ti->error = "Invalid IV mode"; |
636d5786 | 965 | goto bad_ivmode; |
1da177e4 LT |
966 | } |
967 | ||
968 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
969 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 970 | goto bad_ivmode; |
1da177e4 | 971 | |
3a7f6c99 | 972 | cc->iv_size = crypto_ablkcipher_ivsize(tfm); |
d1806f6a | 973 | if (cc->iv_size) |
1da177e4 | 974 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 975 | cc->iv_size = max(cc->iv_size, |
d469f841 | 976 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 977 | else { |
1da177e4 | 978 | if (cc->iv_gen_ops) { |
72d94861 | 979 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
980 | if (cc->iv_gen_ops->dtr) |
981 | cc->iv_gen_ops->dtr(cc); | |
982 | cc->iv_gen_ops = NULL; | |
983 | } | |
984 | } | |
985 | ||
93d2341c | 986 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 987 | if (!cc->io_pool) { |
72d94861 | 988 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 989 | goto bad_slab_pool; |
1da177e4 LT |
990 | } |
991 | ||
ddd42edf | 992 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
3a7f6c99 | 993 | cc->dmreq_start += crypto_ablkcipher_reqsize(tfm); |
ddd42edf | 994 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); |
3a7f6c99 MB |
995 | cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) & |
996 | ~(crypto_tfm_ctx_alignment() - 1); | |
ddd42edf MB |
997 | |
998 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
999 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
1000 | if (!cc->req_pool) { | |
1001 | ti->error = "Cannot allocate crypt request mempool"; | |
1002 | goto bad_req_pool; | |
1003 | } | |
1004 | cc->req = NULL; | |
1005 | ||
a19b27ce | 1006 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 1007 | if (!cc->page_pool) { |
72d94861 | 1008 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 1009 | goto bad_page_pool; |
1da177e4 LT |
1010 | } |
1011 | ||
5972511b | 1012 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
1013 | if (!cc->bs) { |
1014 | ti->error = "Cannot allocate crypt bioset"; | |
1015 | goto bad_bs; | |
1016 | } | |
1017 | ||
3a7f6c99 | 1018 | if (crypto_ablkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 1019 | ti->error = "Error setting key"; |
636d5786 | 1020 | goto bad_device; |
1da177e4 LT |
1021 | } |
1022 | ||
4ee218cd | 1023 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 1024 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 1025 | goto bad_device; |
1da177e4 | 1026 | } |
4ee218cd | 1027 | cc->iv_offset = tmpll; |
1da177e4 | 1028 | |
4ee218cd | 1029 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1030 | ti->error = "Invalid device sector"; |
636d5786 | 1031 | goto bad_device; |
1da177e4 | 1032 | } |
4ee218cd | 1033 | cc->start = tmpll; |
1da177e4 LT |
1034 | |
1035 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 1036 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 1037 | ti->error = "Device lookup failed"; |
636d5786 | 1038 | goto bad_device; |
1da177e4 LT |
1039 | } |
1040 | ||
1041 | if (ivmode && cc->iv_gen_ops) { | |
1042 | if (ivopts) | |
1043 | *(ivopts - 1) = ':'; | |
1044 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
1045 | if (!cc->iv_mode) { | |
72d94861 | 1046 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 1047 | goto bad_ivmode_string; |
1da177e4 LT |
1048 | } |
1049 | strcpy(cc->iv_mode, ivmode); | |
1050 | } else | |
1051 | cc->iv_mode = NULL; | |
1052 | ||
cabf08e4 MB |
1053 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
1054 | if (!cc->io_queue) { | |
1055 | ti->error = "Couldn't create kcryptd io queue"; | |
1056 | goto bad_io_queue; | |
1057 | } | |
1058 | ||
1059 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
1060 | if (!cc->crypt_queue) { | |
9934a8be | 1061 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 1062 | goto bad_crypt_queue; |
9934a8be MB |
1063 | } |
1064 | ||
3f1e9070 | 1065 | init_waitqueue_head(&cc->writeq); |
1da177e4 LT |
1066 | ti->private = cc; |
1067 | return 0; | |
1068 | ||
cabf08e4 MB |
1069 | bad_crypt_queue: |
1070 | destroy_workqueue(cc->io_queue); | |
1071 | bad_io_queue: | |
9934a8be | 1072 | kfree(cc->iv_mode); |
636d5786 | 1073 | bad_ivmode_string: |
55b42c5a | 1074 | dm_put_device(ti, cc->dev); |
636d5786 | 1075 | bad_device: |
6a24c718 MB |
1076 | bioset_free(cc->bs); |
1077 | bad_bs: | |
1da177e4 | 1078 | mempool_destroy(cc->page_pool); |
636d5786 | 1079 | bad_page_pool: |
ddd42edf MB |
1080 | mempool_destroy(cc->req_pool); |
1081 | bad_req_pool: | |
1da177e4 | 1082 | mempool_destroy(cc->io_pool); |
636d5786 | 1083 | bad_slab_pool: |
1da177e4 LT |
1084 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1085 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 1086 | bad_ivmode: |
3a7f6c99 | 1087 | crypto_free_ablkcipher(tfm); |
636d5786 | 1088 | bad_cipher: |
9d3520a3 SR |
1089 | /* Must zero key material before freeing */ |
1090 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1091 | kfree(cc); |
1092 | return -EINVAL; | |
1093 | } | |
1094 | ||
1095 | static void crypt_dtr(struct dm_target *ti) | |
1096 | { | |
1097 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1098 | ||
cabf08e4 MB |
1099 | destroy_workqueue(cc->io_queue); |
1100 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1101 | |
ddd42edf MB |
1102 | if (cc->req) |
1103 | mempool_free(cc->req, cc->req_pool); | |
1104 | ||
6a24c718 | 1105 | bioset_free(cc->bs); |
1da177e4 | 1106 | mempool_destroy(cc->page_pool); |
ddd42edf | 1107 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1108 | mempool_destroy(cc->io_pool); |
1109 | ||
990a8baf | 1110 | kfree(cc->iv_mode); |
1da177e4 LT |
1111 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1112 | cc->iv_gen_ops->dtr(cc); | |
3a7f6c99 | 1113 | crypto_free_ablkcipher(cc->tfm); |
1da177e4 | 1114 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1115 | |
1116 | /* Must zero key material before freeing */ | |
1117 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1118 | kfree(cc); |
1119 | } | |
1120 | ||
1da177e4 LT |
1121 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1122 | union map_info *map_context) | |
1123 | { | |
028867ac | 1124 | struct dm_crypt_io *io; |
1da177e4 | 1125 | |
dc440d1e | 1126 | io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin); |
cabf08e4 MB |
1127 | |
1128 | if (bio_data_dir(io->base_bio) == READ) | |
1129 | kcryptd_queue_io(io); | |
1130 | else | |
1131 | kcryptd_queue_crypt(io); | |
1da177e4 | 1132 | |
d2a7ad29 | 1133 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1134 | } |
1135 | ||
1136 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1137 | char *result, unsigned int maxlen) | |
1138 | { | |
1139 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1140 | unsigned int sz = 0; |
1141 | ||
1142 | switch (type) { | |
1143 | case STATUSTYPE_INFO: | |
1144 | result[0] = '\0'; | |
1145 | break; | |
1146 | ||
1147 | case STATUSTYPE_TABLE: | |
1da177e4 | 1148 | if (cc->iv_mode) |
37af6560 CS |
1149 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1150 | cc->iv_mode); | |
1da177e4 | 1151 | else |
37af6560 | 1152 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1153 | |
1154 | if (cc->key_size > 0) { | |
1155 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1156 | return -ENOMEM; | |
1157 | ||
1158 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1159 | sz += cc->key_size << 1; | |
1160 | } else { | |
1161 | if (sz >= maxlen) | |
1162 | return -ENOMEM; | |
1163 | result[sz++] = '-'; | |
1164 | } | |
1165 | ||
4ee218cd AM |
1166 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1167 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1168 | break; |
1169 | } | |
1170 | return 0; | |
1171 | } | |
1172 | ||
e48d4bbf MB |
1173 | static void crypt_postsuspend(struct dm_target *ti) |
1174 | { | |
1175 | struct crypt_config *cc = ti->private; | |
1176 | ||
1177 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1178 | } | |
1179 | ||
1180 | static int crypt_preresume(struct dm_target *ti) | |
1181 | { | |
1182 | struct crypt_config *cc = ti->private; | |
1183 | ||
1184 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1185 | DMERR("aborting resume - crypt key is not set."); | |
1186 | return -EAGAIN; | |
1187 | } | |
1188 | ||
1189 | return 0; | |
1190 | } | |
1191 | ||
1192 | static void crypt_resume(struct dm_target *ti) | |
1193 | { | |
1194 | struct crypt_config *cc = ti->private; | |
1195 | ||
1196 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1197 | } | |
1198 | ||
1199 | /* Message interface | |
1200 | * key set <key> | |
1201 | * key wipe | |
1202 | */ | |
1203 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1204 | { | |
1205 | struct crypt_config *cc = ti->private; | |
1206 | ||
1207 | if (argc < 2) | |
1208 | goto error; | |
1209 | ||
1210 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1211 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1212 | DMWARN("not suspended during key manipulation."); | |
1213 | return -EINVAL; | |
1214 | } | |
1215 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1216 | return crypt_set_key(cc, argv[2]); | |
1217 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1218 | return crypt_wipe_key(cc); | |
1219 | } | |
1220 | ||
1221 | error: | |
1222 | DMWARN("unrecognised message received."); | |
1223 | return -EINVAL; | |
1224 | } | |
1225 | ||
d41e26b9 MB |
1226 | static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
1227 | struct bio_vec *biovec, int max_size) | |
1228 | { | |
1229 | struct crypt_config *cc = ti->private; | |
1230 | struct request_queue *q = bdev_get_queue(cc->dev->bdev); | |
1231 | ||
1232 | if (!q->merge_bvec_fn) | |
1233 | return max_size; | |
1234 | ||
1235 | bvm->bi_bdev = cc->dev->bdev; | |
1236 | bvm->bi_sector = cc->start + bvm->bi_sector - ti->begin; | |
1237 | ||
1238 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); | |
1239 | } | |
1240 | ||
1da177e4 LT |
1241 | static struct target_type crypt_target = { |
1242 | .name = "crypt", | |
d41e26b9 | 1243 | .version= {1, 6, 0}, |
1da177e4 LT |
1244 | .module = THIS_MODULE, |
1245 | .ctr = crypt_ctr, | |
1246 | .dtr = crypt_dtr, | |
1247 | .map = crypt_map, | |
1248 | .status = crypt_status, | |
e48d4bbf MB |
1249 | .postsuspend = crypt_postsuspend, |
1250 | .preresume = crypt_preresume, | |
1251 | .resume = crypt_resume, | |
1252 | .message = crypt_message, | |
d41e26b9 | 1253 | .merge = crypt_merge, |
1da177e4 LT |
1254 | }; |
1255 | ||
1256 | static int __init dm_crypt_init(void) | |
1257 | { | |
1258 | int r; | |
1259 | ||
028867ac | 1260 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1261 | if (!_crypt_io_pool) |
1262 | return -ENOMEM; | |
1263 | ||
1da177e4 LT |
1264 | r = dm_register_target(&crypt_target); |
1265 | if (r < 0) { | |
72d94861 | 1266 | DMERR("register failed %d", r); |
9934a8be | 1267 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1268 | } |
1269 | ||
1da177e4 LT |
1270 | return r; |
1271 | } | |
1272 | ||
1273 | static void __exit dm_crypt_exit(void) | |
1274 | { | |
1275 | int r = dm_unregister_target(&crypt_target); | |
1276 | ||
1277 | if (r < 0) | |
72d94861 | 1278 | DMERR("unregister failed %d", r); |
1da177e4 | 1279 | |
1da177e4 LT |
1280 | kmem_cache_destroy(_crypt_io_pool); |
1281 | } | |
1282 | ||
1283 | module_init(dm_crypt_init); | |
1284 | module_exit(dm_crypt_exit); | |
1285 | ||
1286 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1287 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1288 | MODULE_LICENSE("GPL"); |