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 | 25 | |
586e80e6 | 26 | #include <linux/device-mapper.h> |
1da177e4 | 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; |
393b47ef | 59 | struct dm_crypt_io *base_io; |
53017030 MB |
60 | }; |
61 | ||
01482b76 MB |
62 | struct dm_crypt_request { |
63 | struct scatterlist sg_in; | |
64 | struct scatterlist sg_out; | |
65 | }; | |
66 | ||
1da177e4 LT |
67 | struct crypt_config; |
68 | ||
69 | struct crypt_iv_operations { | |
70 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 71 | const char *opts); |
1da177e4 LT |
72 | void (*dtr)(struct crypt_config *cc); |
73 | const char *(*status)(struct crypt_config *cc); | |
74 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
75 | }; | |
76 | ||
77 | /* | |
78 | * Crypt: maps a linear range of a block device | |
79 | * and encrypts / decrypts at the same time. | |
80 | */ | |
e48d4bbf | 81 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
82 | struct crypt_config { |
83 | struct dm_dev *dev; | |
84 | sector_t start; | |
85 | ||
86 | /* | |
ddd42edf MB |
87 | * pool for per bio private data, crypto requests and |
88 | * encryption requeusts/buffer pages | |
1da177e4 LT |
89 | */ |
90 | mempool_t *io_pool; | |
ddd42edf | 91 | mempool_t *req_pool; |
1da177e4 | 92 | mempool_t *page_pool; |
6a24c718 | 93 | struct bio_set *bs; |
1da177e4 | 94 | |
cabf08e4 MB |
95 | struct workqueue_struct *io_queue; |
96 | struct workqueue_struct *crypt_queue; | |
3f1e9070 | 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); |
1da177e4 LT |
336 | } |
337 | ||
01482b76 | 338 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
339 | struct convert_context *ctx, |
340 | struct ablkcipher_request *req) | |
01482b76 MB |
341 | { |
342 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
343 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
3a7f6c99 MB |
344 | struct dm_crypt_request *dmreq; |
345 | u8 *iv; | |
346 | int r = 0; | |
347 | ||
348 | dmreq = (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
349 | iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), | |
350 | crypto_ablkcipher_alignmask(cc->tfm) + 1); | |
01482b76 | 351 | |
3a7f6c99 MB |
352 | sg_init_table(&dmreq->sg_in, 1); |
353 | sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
354 | bv_in->bv_offset + ctx->offset_in); |
355 | ||
3a7f6c99 MB |
356 | sg_init_table(&dmreq->sg_out, 1); |
357 | sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
358 | bv_out->bv_offset + ctx->offset_out); |
359 | ||
360 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
361 | if (ctx->offset_in >= bv_in->bv_len) { | |
362 | ctx->offset_in = 0; | |
363 | ctx->idx_in++; | |
364 | } | |
365 | ||
366 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
367 | if (ctx->offset_out >= bv_out->bv_len) { | |
368 | ctx->offset_out = 0; | |
369 | ctx->idx_out++; | |
370 | } | |
371 | ||
3a7f6c99 MB |
372 | if (cc->iv_gen_ops) { |
373 | r = cc->iv_gen_ops->generator(cc, iv, ctx->sector); | |
374 | if (r < 0) | |
375 | return r; | |
376 | } | |
377 | ||
378 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
379 | 1 << SECTOR_SHIFT, iv); | |
380 | ||
381 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
382 | r = crypto_ablkcipher_encrypt(req); | |
383 | else | |
384 | r = crypto_ablkcipher_decrypt(req); | |
385 | ||
386 | return r; | |
01482b76 MB |
387 | } |
388 | ||
95497a96 MB |
389 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
390 | int error); | |
ddd42edf MB |
391 | static void crypt_alloc_req(struct crypt_config *cc, |
392 | struct convert_context *ctx) | |
393 | { | |
394 | if (!cc->req) | |
395 | cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
95497a96 MB |
396 | ablkcipher_request_set_tfm(cc->req, cc->tfm); |
397 | ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | | |
398 | CRYPTO_TFM_REQ_MAY_SLEEP, | |
399 | kcryptd_async_done, ctx); | |
ddd42edf MB |
400 | } |
401 | ||
1da177e4 LT |
402 | /* |
403 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
404 | */ | |
405 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 406 | struct convert_context *ctx) |
1da177e4 | 407 | { |
3f1e9070 | 408 | int r; |
1da177e4 | 409 | |
c8081618 MB |
410 | atomic_set(&ctx->pending, 1); |
411 | ||
1da177e4 LT |
412 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && |
413 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
1da177e4 | 414 | |
3a7f6c99 MB |
415 | crypt_alloc_req(cc, ctx); |
416 | ||
3f1e9070 MB |
417 | atomic_inc(&ctx->pending); |
418 | ||
3a7f6c99 MB |
419 | r = crypt_convert_block(cc, ctx, cc->req); |
420 | ||
421 | switch (r) { | |
3f1e9070 | 422 | /* async */ |
3a7f6c99 MB |
423 | case -EBUSY: |
424 | wait_for_completion(&ctx->restart); | |
425 | INIT_COMPLETION(ctx->restart); | |
426 | /* fall through*/ | |
427 | case -EINPROGRESS: | |
3a7f6c99 | 428 | cc->req = NULL; |
3f1e9070 MB |
429 | ctx->sector++; |
430 | continue; | |
431 | ||
432 | /* sync */ | |
3a7f6c99 | 433 | case 0: |
3f1e9070 | 434 | atomic_dec(&ctx->pending); |
3a7f6c99 | 435 | ctx->sector++; |
c7f1b204 | 436 | cond_resched(); |
3a7f6c99 | 437 | continue; |
3a7f6c99 | 438 | |
3f1e9070 MB |
439 | /* error */ |
440 | default: | |
441 | atomic_dec(&ctx->pending); | |
442 | return r; | |
443 | } | |
1da177e4 LT |
444 | } |
445 | ||
3f1e9070 | 446 | return 0; |
1da177e4 LT |
447 | } |
448 | ||
d469f841 MB |
449 | static void dm_crypt_bio_destructor(struct bio *bio) |
450 | { | |
028867ac | 451 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
452 | struct crypt_config *cc = io->target->private; |
453 | ||
454 | bio_free(bio, cc->bs); | |
d469f841 | 455 | } |
6a24c718 | 456 | |
1da177e4 LT |
457 | /* |
458 | * Generate a new unfragmented bio with the given size | |
459 | * This should never violate the device limitations | |
933f01d4 MB |
460 | * May return a smaller bio when running out of pages, indicated by |
461 | * *out_of_pages set to 1. | |
1da177e4 | 462 | */ |
933f01d4 MB |
463 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size, |
464 | unsigned *out_of_pages) | |
1da177e4 | 465 | { |
027581f3 | 466 | struct crypt_config *cc = io->target->private; |
8b004457 | 467 | struct bio *clone; |
1da177e4 | 468 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 469 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
470 | unsigned i, len; |
471 | struct page *page; | |
1da177e4 | 472 | |
2f9941b6 | 473 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 474 | if (!clone) |
1da177e4 | 475 | return NULL; |
1da177e4 | 476 | |
027581f3 | 477 | clone_init(io, clone); |
933f01d4 | 478 | *out_of_pages = 0; |
6a24c718 | 479 | |
f97380bc | 480 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 | 481 | page = mempool_alloc(cc->page_pool, gfp_mask); |
933f01d4 MB |
482 | if (!page) { |
483 | *out_of_pages = 1; | |
1da177e4 | 484 | break; |
933f01d4 | 485 | } |
1da177e4 LT |
486 | |
487 | /* | |
488 | * if additional pages cannot be allocated without waiting, | |
489 | * return a partially allocated bio, the caller will then try | |
490 | * to allocate additional bios while submitting this partial bio | |
491 | */ | |
f97380bc | 492 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
493 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
494 | ||
91e10625 MB |
495 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
496 | ||
497 | if (!bio_add_page(clone, page, len, 0)) { | |
498 | mempool_free(page, cc->page_pool); | |
499 | break; | |
500 | } | |
1da177e4 | 501 | |
91e10625 | 502 | size -= len; |
1da177e4 LT |
503 | } |
504 | ||
8b004457 MB |
505 | if (!clone->bi_size) { |
506 | bio_put(clone); | |
1da177e4 LT |
507 | return NULL; |
508 | } | |
509 | ||
8b004457 | 510 | return clone; |
1da177e4 LT |
511 | } |
512 | ||
644bd2f0 | 513 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 514 | { |
644bd2f0 | 515 | unsigned int i; |
1da177e4 LT |
516 | struct bio_vec *bv; |
517 | ||
644bd2f0 | 518 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 519 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
520 | BUG_ON(!bv->bv_page); |
521 | mempool_free(bv->bv_page, cc->page_pool); | |
522 | bv->bv_page = NULL; | |
523 | } | |
524 | } | |
525 | ||
dc440d1e MB |
526 | static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti, |
527 | struct bio *bio, sector_t sector) | |
528 | { | |
529 | struct crypt_config *cc = ti->private; | |
530 | struct dm_crypt_io *io; | |
531 | ||
532 | io = mempool_alloc(cc->io_pool, GFP_NOIO); | |
533 | io->target = ti; | |
534 | io->base_bio = bio; | |
535 | io->sector = sector; | |
536 | io->error = 0; | |
393b47ef | 537 | io->base_io = NULL; |
dc440d1e MB |
538 | atomic_set(&io->pending, 0); |
539 | ||
540 | return io; | |
541 | } | |
542 | ||
3e1a8bdd MB |
543 | static void crypt_inc_pending(struct dm_crypt_io *io) |
544 | { | |
545 | atomic_inc(&io->pending); | |
546 | } | |
547 | ||
1da177e4 LT |
548 | /* |
549 | * One of the bios was finished. Check for completion of | |
550 | * the whole request and correctly clean up the buffer. | |
393b47ef | 551 | * If base_io is set, wait for the last fragment to complete. |
1da177e4 | 552 | */ |
5742fd77 | 553 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 554 | { |
5742fd77 | 555 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
556 | |
557 | if (!atomic_dec_and_test(&io->pending)) | |
558 | return; | |
559 | ||
393b47ef MB |
560 | if (likely(!io->base_io)) |
561 | bio_endio(io->base_bio, io->error); | |
562 | else { | |
563 | if (io->error && !io->base_io->error) | |
564 | io->base_io->error = io->error; | |
565 | crypt_dec_pending(io->base_io); | |
566 | } | |
567 | ||
1da177e4 LT |
568 | mempool_free(io, cc->io_pool); |
569 | } | |
570 | ||
571 | /* | |
cabf08e4 | 572 | * kcryptd/kcryptd_io: |
1da177e4 LT |
573 | * |
574 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 575 | * interrupt context. |
cabf08e4 MB |
576 | * |
577 | * kcryptd performs the actual encryption or decryption. | |
578 | * | |
579 | * kcryptd_io performs the IO submission. | |
580 | * | |
581 | * They must be separated as otherwise the final stages could be | |
582 | * starved by new requests which can block in the first stages due | |
583 | * to memory allocation. | |
1da177e4 | 584 | */ |
6712ecf8 | 585 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 586 | { |
028867ac | 587 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 588 | struct crypt_config *cc = io->target->private; |
ee7a491e | 589 | unsigned rw = bio_data_dir(clone); |
8b004457 | 590 | |
adfe4770 MB |
591 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
592 | error = -EIO; | |
593 | ||
8b004457 | 594 | /* |
6712ecf8 | 595 | * free the processed pages |
8b004457 | 596 | */ |
ee7a491e | 597 | if (rw == WRITE) |
644bd2f0 | 598 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
599 | |
600 | bio_put(clone); | |
8b004457 | 601 | |
ee7a491e MB |
602 | if (rw == READ && !error) { |
603 | kcryptd_queue_crypt(io); | |
604 | return; | |
605 | } | |
5742fd77 MB |
606 | |
607 | if (unlikely(error)) | |
608 | io->error = error; | |
609 | ||
610 | crypt_dec_pending(io); | |
8b004457 MB |
611 | } |
612 | ||
028867ac | 613 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
614 | { |
615 | struct crypt_config *cc = io->target->private; | |
616 | ||
617 | clone->bi_private = io; | |
618 | clone->bi_end_io = crypt_endio; | |
619 | clone->bi_bdev = cc->dev->bdev; | |
620 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 621 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
622 | } |
623 | ||
4e4eef64 | 624 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
625 | { |
626 | struct crypt_config *cc = io->target->private; | |
627 | struct bio *base_bio = io->base_bio; | |
628 | struct bio *clone; | |
93e605c2 | 629 | |
3e1a8bdd | 630 | crypt_inc_pending(io); |
8b004457 MB |
631 | |
632 | /* | |
633 | * The block layer might modify the bvec array, so always | |
634 | * copy the required bvecs because we need the original | |
635 | * one in order to decrypt the whole bio data *afterwards*. | |
636 | */ | |
6a24c718 | 637 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 638 | if (unlikely(!clone)) { |
5742fd77 MB |
639 | io->error = -ENOMEM; |
640 | crypt_dec_pending(io); | |
23541d2d | 641 | return; |
93e605c2 | 642 | } |
8b004457 MB |
643 | |
644 | clone_init(io, clone); | |
645 | clone->bi_idx = 0; | |
646 | clone->bi_vcnt = bio_segments(base_bio); | |
647 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 648 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
649 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
650 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 651 | |
93e605c2 | 652 | generic_make_request(clone); |
8b004457 MB |
653 | } |
654 | ||
4e4eef64 MB |
655 | static void kcryptd_io_write(struct dm_crypt_io *io) |
656 | { | |
95497a96 | 657 | struct bio *clone = io->ctx.bio_out; |
95497a96 | 658 | generic_make_request(clone); |
4e4eef64 MB |
659 | } |
660 | ||
395b167c AK |
661 | static void kcryptd_io(struct work_struct *work) |
662 | { | |
663 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
664 | ||
665 | if (bio_data_dir(io->base_bio) == READ) | |
666 | kcryptd_io_read(io); | |
667 | else | |
668 | kcryptd_io_write(io); | |
669 | } | |
670 | ||
671 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
672 | { | |
673 | struct crypt_config *cc = io->target->private; | |
674 | ||
675 | INIT_WORK(&io->work, kcryptd_io); | |
676 | queue_work(cc->io_queue, &io->work); | |
677 | } | |
678 | ||
95497a96 MB |
679 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
680 | int error, int async) | |
4e4eef64 | 681 | { |
dec1cedf MB |
682 | struct bio *clone = io->ctx.bio_out; |
683 | struct crypt_config *cc = io->target->private; | |
684 | ||
685 | if (unlikely(error < 0)) { | |
686 | crypt_free_buffer_pages(cc, clone); | |
687 | bio_put(clone); | |
688 | io->error = -EIO; | |
6c031f41 | 689 | crypt_dec_pending(io); |
dec1cedf MB |
690 | return; |
691 | } | |
692 | ||
693 | /* crypt_convert should have filled the clone bio */ | |
694 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
695 | ||
696 | clone->bi_sector = cc->start + io->sector; | |
899c95d3 | 697 | |
95497a96 MB |
698 | if (async) |
699 | kcryptd_queue_io(io); | |
1e37bb8e | 700 | else |
95497a96 | 701 | generic_make_request(clone); |
4e4eef64 MB |
702 | } |
703 | ||
fc5a5e9a | 704 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
8b004457 MB |
705 | { |
706 | struct crypt_config *cc = io->target->private; | |
8b004457 | 707 | struct bio *clone; |
393b47ef | 708 | struct dm_crypt_io *new_io; |
c8081618 | 709 | int crypt_finished; |
933f01d4 | 710 | unsigned out_of_pages = 0; |
dec1cedf | 711 | unsigned remaining = io->base_bio->bi_size; |
b635b00e | 712 | sector_t sector = io->sector; |
dec1cedf | 713 | int r; |
8b004457 | 714 | |
fc5a5e9a MB |
715 | /* |
716 | * Prevent io from disappearing until this function completes. | |
717 | */ | |
718 | crypt_inc_pending(io); | |
b635b00e | 719 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector); |
fc5a5e9a | 720 | |
93e605c2 MB |
721 | /* |
722 | * The allocated buffers can be smaller than the whole bio, | |
723 | * so repeat the whole process until all the data can be handled. | |
724 | */ | |
725 | while (remaining) { | |
933f01d4 | 726 | clone = crypt_alloc_buffer(io, remaining, &out_of_pages); |
23541d2d | 727 | if (unlikely(!clone)) { |
5742fd77 | 728 | io->error = -ENOMEM; |
fc5a5e9a | 729 | break; |
23541d2d | 730 | } |
93e605c2 | 731 | |
53017030 MB |
732 | io->ctx.bio_out = clone; |
733 | io->ctx.idx_out = 0; | |
93e605c2 | 734 | |
dec1cedf | 735 | remaining -= clone->bi_size; |
b635b00e | 736 | sector += bio_sectors(clone); |
93e605c2 | 737 | |
4e594098 | 738 | crypt_inc_pending(io); |
dec1cedf | 739 | r = crypt_convert(cc, &io->ctx); |
c8081618 | 740 | crypt_finished = atomic_dec_and_test(&io->ctx.pending); |
f97380bc | 741 | |
c8081618 MB |
742 | /* Encryption was already finished, submit io now */ |
743 | if (crypt_finished) { | |
3a7f6c99 | 744 | kcryptd_crypt_write_io_submit(io, r, 0); |
c8081618 MB |
745 | |
746 | /* | |
747 | * If there was an error, do not try next fragments. | |
748 | * For async, error is processed in async handler. | |
749 | */ | |
6c031f41 | 750 | if (unlikely(r < 0)) |
fc5a5e9a | 751 | break; |
b635b00e MB |
752 | |
753 | io->sector = sector; | |
4e594098 | 754 | } |
93e605c2 | 755 | |
933f01d4 MB |
756 | /* |
757 | * Out of memory -> run queues | |
758 | * But don't wait if split was due to the io size restriction | |
759 | */ | |
760 | if (unlikely(out_of_pages)) | |
98221eb7 | 761 | congestion_wait(WRITE, HZ/100); |
933f01d4 | 762 | |
393b47ef MB |
763 | /* |
764 | * With async crypto it is unsafe to share the crypto context | |
765 | * between fragments, so switch to a new dm_crypt_io structure. | |
766 | */ | |
767 | if (unlikely(!crypt_finished && remaining)) { | |
768 | new_io = crypt_io_alloc(io->target, io->base_bio, | |
769 | sector); | |
770 | crypt_inc_pending(new_io); | |
771 | crypt_convert_init(cc, &new_io->ctx, NULL, | |
772 | io->base_bio, sector); | |
773 | new_io->ctx.idx_in = io->ctx.idx_in; | |
774 | new_io->ctx.offset_in = io->ctx.offset_in; | |
775 | ||
776 | /* | |
777 | * Fragments after the first use the base_io | |
778 | * pending count. | |
779 | */ | |
780 | if (!io->base_io) | |
781 | new_io->base_io = io; | |
782 | else { | |
783 | new_io->base_io = io->base_io; | |
784 | crypt_inc_pending(io->base_io); | |
785 | crypt_dec_pending(io); | |
786 | } | |
787 | ||
788 | io = new_io; | |
789 | } | |
93e605c2 | 790 | } |
899c95d3 MB |
791 | |
792 | crypt_dec_pending(io); | |
84131db6 MB |
793 | } |
794 | ||
4e4eef64 | 795 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
796 | { |
797 | if (unlikely(error < 0)) | |
798 | io->error = -EIO; | |
799 | ||
800 | crypt_dec_pending(io); | |
801 | } | |
802 | ||
4e4eef64 | 803 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
804 | { |
805 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 806 | int r = 0; |
1da177e4 | 807 | |
3e1a8bdd | 808 | crypt_inc_pending(io); |
3a7f6c99 | 809 | |
53017030 | 810 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 811 | io->sector); |
1da177e4 | 812 | |
5742fd77 MB |
813 | r = crypt_convert(cc, &io->ctx); |
814 | ||
3f1e9070 | 815 | if (atomic_dec_and_test(&io->ctx.pending)) |
3a7f6c99 MB |
816 | kcryptd_crypt_read_done(io, r); |
817 | ||
818 | crypt_dec_pending(io); | |
1da177e4 LT |
819 | } |
820 | ||
95497a96 MB |
821 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
822 | int error) | |
823 | { | |
824 | struct convert_context *ctx = async_req->data; | |
825 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); | |
826 | struct crypt_config *cc = io->target->private; | |
827 | ||
828 | if (error == -EINPROGRESS) { | |
829 | complete(&ctx->restart); | |
830 | return; | |
831 | } | |
832 | ||
833 | mempool_free(ablkcipher_request_cast(async_req), cc->req_pool); | |
834 | ||
835 | if (!atomic_dec_and_test(&ctx->pending)) | |
836 | return; | |
837 | ||
838 | if (bio_data_dir(io->base_bio) == READ) | |
839 | kcryptd_crypt_read_done(io, error); | |
840 | else | |
841 | kcryptd_crypt_write_io_submit(io, error, 1); | |
842 | } | |
843 | ||
395b167c | 844 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 845 | { |
028867ac | 846 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 847 | |
cabf08e4 | 848 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 849 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 850 | else |
395b167c | 851 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
852 | } |
853 | ||
395b167c | 854 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 855 | { |
395b167c | 856 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 857 | |
395b167c AK |
858 | INIT_WORK(&io->work, kcryptd_crypt); |
859 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
860 | } |
861 | ||
862 | /* | |
863 | * Decode key from its hex representation | |
864 | */ | |
865 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
866 | { | |
867 | char buffer[3]; | |
868 | char *endp; | |
869 | unsigned int i; | |
870 | ||
871 | buffer[2] = '\0'; | |
872 | ||
8b004457 | 873 | for (i = 0; i < size; i++) { |
1da177e4 LT |
874 | buffer[0] = *hex++; |
875 | buffer[1] = *hex++; | |
876 | ||
877 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
878 | ||
879 | if (endp != &buffer[2]) | |
880 | return -EINVAL; | |
881 | } | |
882 | ||
883 | if (*hex != '\0') | |
884 | return -EINVAL; | |
885 | ||
886 | return 0; | |
887 | } | |
888 | ||
889 | /* | |
890 | * Encode key into its hex representation | |
891 | */ | |
892 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
893 | { | |
894 | unsigned int i; | |
895 | ||
8b004457 | 896 | for (i = 0; i < size; i++) { |
1da177e4 LT |
897 | sprintf(hex, "%02x", *key); |
898 | hex += 2; | |
899 | key++; | |
900 | } | |
901 | } | |
902 | ||
e48d4bbf MB |
903 | static int crypt_set_key(struct crypt_config *cc, char *key) |
904 | { | |
905 | unsigned key_size = strlen(key) >> 1; | |
906 | ||
907 | if (cc->key_size && cc->key_size != key_size) | |
908 | return -EINVAL; | |
909 | ||
910 | cc->key_size = key_size; /* initial settings */ | |
911 | ||
912 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 913 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
914 | return -EINVAL; |
915 | ||
916 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
917 | ||
918 | return 0; | |
919 | } | |
920 | ||
921 | static int crypt_wipe_key(struct crypt_config *cc) | |
922 | { | |
923 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
924 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
925 | return 0; | |
926 | } | |
927 | ||
1da177e4 LT |
928 | /* |
929 | * Construct an encryption mapping: | |
930 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
931 | */ | |
932 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
933 | { | |
934 | struct crypt_config *cc; | |
3a7f6c99 | 935 | struct crypto_ablkcipher *tfm; |
1da177e4 LT |
936 | char *tmp; |
937 | char *cipher; | |
938 | char *chainmode; | |
939 | char *ivmode; | |
940 | char *ivopts; | |
1da177e4 | 941 | unsigned int key_size; |
4ee218cd | 942 | unsigned long long tmpll; |
1da177e4 LT |
943 | |
944 | if (argc != 5) { | |
72d94861 | 945 | ti->error = "Not enough arguments"; |
1da177e4 LT |
946 | return -EINVAL; |
947 | } | |
948 | ||
949 | tmp = argv[0]; | |
950 | cipher = strsep(&tmp, "-"); | |
951 | chainmode = strsep(&tmp, "-"); | |
952 | ivopts = strsep(&tmp, "-"); | |
953 | ivmode = strsep(&ivopts, ":"); | |
954 | ||
955 | if (tmp) | |
72d94861 | 956 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
957 | |
958 | key_size = strlen(argv[1]) >> 1; | |
959 | ||
e48d4bbf | 960 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
961 | if (cc == NULL) { |
962 | ti->error = | |
72d94861 | 963 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
964 | return -ENOMEM; |
965 | } | |
966 | ||
e48d4bbf | 967 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 968 | ti->error = "Error decoding key"; |
636d5786 | 969 | goto bad_cipher; |
1da177e4 LT |
970 | } |
971 | ||
972 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
973 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
974 | chainmode = "cbc"; | |
975 | ivmode = "plain"; | |
976 | } | |
977 | ||
d1806f6a HX |
978 | if (strcmp(chainmode, "ecb") && !ivmode) { |
979 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 980 | goto bad_cipher; |
1da177e4 LT |
981 | } |
982 | ||
d469f841 MB |
983 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
984 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 985 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 986 | goto bad_cipher; |
1da177e4 LT |
987 | } |
988 | ||
3a7f6c99 | 989 | tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0); |
d1806f6a | 990 | if (IS_ERR(tfm)) { |
72d94861 | 991 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 992 | goto bad_cipher; |
1da177e4 | 993 | } |
1da177e4 | 994 | |
d1806f6a HX |
995 | strcpy(cc->cipher, cipher); |
996 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
997 | cc->tfm = tfm; |
998 | ||
999 | /* | |
48527fa7 | 1000 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
1001 | * See comments at iv code |
1002 | */ | |
1003 | ||
1004 | if (ivmode == NULL) | |
1005 | cc->iv_gen_ops = NULL; | |
1006 | else if (strcmp(ivmode, "plain") == 0) | |
1007 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
1008 | else if (strcmp(ivmode, "essiv") == 0) | |
1009 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
1010 | else if (strcmp(ivmode, "benbi") == 0) |
1011 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
1012 | else if (strcmp(ivmode, "null") == 0) |
1013 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 1014 | else { |
72d94861 | 1015 | ti->error = "Invalid IV mode"; |
636d5786 | 1016 | goto bad_ivmode; |
1da177e4 LT |
1017 | } |
1018 | ||
1019 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
1020 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 1021 | goto bad_ivmode; |
1da177e4 | 1022 | |
3a7f6c99 | 1023 | cc->iv_size = crypto_ablkcipher_ivsize(tfm); |
d1806f6a | 1024 | if (cc->iv_size) |
1da177e4 | 1025 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 1026 | cc->iv_size = max(cc->iv_size, |
d469f841 | 1027 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 1028 | else { |
1da177e4 | 1029 | if (cc->iv_gen_ops) { |
72d94861 | 1030 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
1031 | if (cc->iv_gen_ops->dtr) |
1032 | cc->iv_gen_ops->dtr(cc); | |
1033 | cc->iv_gen_ops = NULL; | |
1034 | } | |
1035 | } | |
1036 | ||
93d2341c | 1037 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 1038 | if (!cc->io_pool) { |
72d94861 | 1039 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 1040 | goto bad_slab_pool; |
1da177e4 LT |
1041 | } |
1042 | ||
ddd42edf | 1043 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
3a7f6c99 | 1044 | cc->dmreq_start += crypto_ablkcipher_reqsize(tfm); |
ddd42edf | 1045 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); |
3a7f6c99 MB |
1046 | cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) & |
1047 | ~(crypto_tfm_ctx_alignment() - 1); | |
ddd42edf MB |
1048 | |
1049 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
1050 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
1051 | if (!cc->req_pool) { | |
1052 | ti->error = "Cannot allocate crypt request mempool"; | |
1053 | goto bad_req_pool; | |
1054 | } | |
1055 | cc->req = NULL; | |
1056 | ||
a19b27ce | 1057 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 1058 | if (!cc->page_pool) { |
72d94861 | 1059 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 1060 | goto bad_page_pool; |
1da177e4 LT |
1061 | } |
1062 | ||
5972511b | 1063 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
1064 | if (!cc->bs) { |
1065 | ti->error = "Cannot allocate crypt bioset"; | |
1066 | goto bad_bs; | |
1067 | } | |
1068 | ||
3a7f6c99 | 1069 | if (crypto_ablkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 1070 | ti->error = "Error setting key"; |
636d5786 | 1071 | goto bad_device; |
1da177e4 LT |
1072 | } |
1073 | ||
4ee218cd | 1074 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 1075 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 1076 | goto bad_device; |
1da177e4 | 1077 | } |
4ee218cd | 1078 | cc->iv_offset = tmpll; |
1da177e4 | 1079 | |
4ee218cd | 1080 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1081 | ti->error = "Invalid device sector"; |
636d5786 | 1082 | goto bad_device; |
1da177e4 | 1083 | } |
4ee218cd | 1084 | cc->start = tmpll; |
1da177e4 LT |
1085 | |
1086 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 1087 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 1088 | ti->error = "Device lookup failed"; |
636d5786 | 1089 | goto bad_device; |
1da177e4 LT |
1090 | } |
1091 | ||
1092 | if (ivmode && cc->iv_gen_ops) { | |
1093 | if (ivopts) | |
1094 | *(ivopts - 1) = ':'; | |
1095 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
1096 | if (!cc->iv_mode) { | |
72d94861 | 1097 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 1098 | goto bad_ivmode_string; |
1da177e4 LT |
1099 | } |
1100 | strcpy(cc->iv_mode, ivmode); | |
1101 | } else | |
1102 | cc->iv_mode = NULL; | |
1103 | ||
cabf08e4 MB |
1104 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
1105 | if (!cc->io_queue) { | |
1106 | ti->error = "Couldn't create kcryptd io queue"; | |
1107 | goto bad_io_queue; | |
1108 | } | |
1109 | ||
1110 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
1111 | if (!cc->crypt_queue) { | |
9934a8be | 1112 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 1113 | goto bad_crypt_queue; |
9934a8be MB |
1114 | } |
1115 | ||
1da177e4 LT |
1116 | ti->private = cc; |
1117 | return 0; | |
1118 | ||
cabf08e4 MB |
1119 | bad_crypt_queue: |
1120 | destroy_workqueue(cc->io_queue); | |
1121 | bad_io_queue: | |
9934a8be | 1122 | kfree(cc->iv_mode); |
636d5786 | 1123 | bad_ivmode_string: |
55b42c5a | 1124 | dm_put_device(ti, cc->dev); |
636d5786 | 1125 | bad_device: |
6a24c718 MB |
1126 | bioset_free(cc->bs); |
1127 | bad_bs: | |
1da177e4 | 1128 | mempool_destroy(cc->page_pool); |
636d5786 | 1129 | bad_page_pool: |
ddd42edf MB |
1130 | mempool_destroy(cc->req_pool); |
1131 | bad_req_pool: | |
1da177e4 | 1132 | mempool_destroy(cc->io_pool); |
636d5786 | 1133 | bad_slab_pool: |
1da177e4 LT |
1134 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1135 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 1136 | bad_ivmode: |
3a7f6c99 | 1137 | crypto_free_ablkcipher(tfm); |
636d5786 | 1138 | bad_cipher: |
9d3520a3 SR |
1139 | /* Must zero key material before freeing */ |
1140 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1141 | kfree(cc); |
1142 | return -EINVAL; | |
1143 | } | |
1144 | ||
1145 | static void crypt_dtr(struct dm_target *ti) | |
1146 | { | |
1147 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1148 | ||
cabf08e4 MB |
1149 | destroy_workqueue(cc->io_queue); |
1150 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1151 | |
ddd42edf MB |
1152 | if (cc->req) |
1153 | mempool_free(cc->req, cc->req_pool); | |
1154 | ||
6a24c718 | 1155 | bioset_free(cc->bs); |
1da177e4 | 1156 | mempool_destroy(cc->page_pool); |
ddd42edf | 1157 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1158 | mempool_destroy(cc->io_pool); |
1159 | ||
990a8baf | 1160 | kfree(cc->iv_mode); |
1da177e4 LT |
1161 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1162 | cc->iv_gen_ops->dtr(cc); | |
3a7f6c99 | 1163 | crypto_free_ablkcipher(cc->tfm); |
1da177e4 | 1164 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1165 | |
1166 | /* Must zero key material before freeing */ | |
1167 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1168 | kfree(cc); |
1169 | } | |
1170 | ||
1da177e4 LT |
1171 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1172 | union map_info *map_context) | |
1173 | { | |
028867ac | 1174 | struct dm_crypt_io *io; |
1da177e4 | 1175 | |
dc440d1e | 1176 | io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin); |
cabf08e4 MB |
1177 | |
1178 | if (bio_data_dir(io->base_bio) == READ) | |
1179 | kcryptd_queue_io(io); | |
1180 | else | |
1181 | kcryptd_queue_crypt(io); | |
1da177e4 | 1182 | |
d2a7ad29 | 1183 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1184 | } |
1185 | ||
1186 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1187 | char *result, unsigned int maxlen) | |
1188 | { | |
1189 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1190 | unsigned int sz = 0; |
1191 | ||
1192 | switch (type) { | |
1193 | case STATUSTYPE_INFO: | |
1194 | result[0] = '\0'; | |
1195 | break; | |
1196 | ||
1197 | case STATUSTYPE_TABLE: | |
1da177e4 | 1198 | if (cc->iv_mode) |
37af6560 CS |
1199 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1200 | cc->iv_mode); | |
1da177e4 | 1201 | else |
37af6560 | 1202 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1203 | |
1204 | if (cc->key_size > 0) { | |
1205 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1206 | return -ENOMEM; | |
1207 | ||
1208 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1209 | sz += cc->key_size << 1; | |
1210 | } else { | |
1211 | if (sz >= maxlen) | |
1212 | return -ENOMEM; | |
1213 | result[sz++] = '-'; | |
1214 | } | |
1215 | ||
4ee218cd AM |
1216 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1217 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1218 | break; |
1219 | } | |
1220 | return 0; | |
1221 | } | |
1222 | ||
e48d4bbf MB |
1223 | static void crypt_postsuspend(struct dm_target *ti) |
1224 | { | |
1225 | struct crypt_config *cc = ti->private; | |
1226 | ||
1227 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1228 | } | |
1229 | ||
1230 | static int crypt_preresume(struct dm_target *ti) | |
1231 | { | |
1232 | struct crypt_config *cc = ti->private; | |
1233 | ||
1234 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1235 | DMERR("aborting resume - crypt key is not set."); | |
1236 | return -EAGAIN; | |
1237 | } | |
1238 | ||
1239 | return 0; | |
1240 | } | |
1241 | ||
1242 | static void crypt_resume(struct dm_target *ti) | |
1243 | { | |
1244 | struct crypt_config *cc = ti->private; | |
1245 | ||
1246 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1247 | } | |
1248 | ||
1249 | /* Message interface | |
1250 | * key set <key> | |
1251 | * key wipe | |
1252 | */ | |
1253 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1254 | { | |
1255 | struct crypt_config *cc = ti->private; | |
1256 | ||
1257 | if (argc < 2) | |
1258 | goto error; | |
1259 | ||
1260 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1261 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1262 | DMWARN("not suspended during key manipulation."); | |
1263 | return -EINVAL; | |
1264 | } | |
1265 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1266 | return crypt_set_key(cc, argv[2]); | |
1267 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1268 | return crypt_wipe_key(cc); | |
1269 | } | |
1270 | ||
1271 | error: | |
1272 | DMWARN("unrecognised message received."); | |
1273 | return -EINVAL; | |
1274 | } | |
1275 | ||
d41e26b9 MB |
1276 | static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
1277 | struct bio_vec *biovec, int max_size) | |
1278 | { | |
1279 | struct crypt_config *cc = ti->private; | |
1280 | struct request_queue *q = bdev_get_queue(cc->dev->bdev); | |
1281 | ||
1282 | if (!q->merge_bvec_fn) | |
1283 | return max_size; | |
1284 | ||
1285 | bvm->bi_bdev = cc->dev->bdev; | |
1286 | bvm->bi_sector = cc->start + bvm->bi_sector - ti->begin; | |
1287 | ||
1288 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); | |
1289 | } | |
1290 | ||
1da177e4 LT |
1291 | static struct target_type crypt_target = { |
1292 | .name = "crypt", | |
d41e26b9 | 1293 | .version= {1, 6, 0}, |
1da177e4 LT |
1294 | .module = THIS_MODULE, |
1295 | .ctr = crypt_ctr, | |
1296 | .dtr = crypt_dtr, | |
1297 | .map = crypt_map, | |
1298 | .status = crypt_status, | |
e48d4bbf MB |
1299 | .postsuspend = crypt_postsuspend, |
1300 | .preresume = crypt_preresume, | |
1301 | .resume = crypt_resume, | |
1302 | .message = crypt_message, | |
d41e26b9 | 1303 | .merge = crypt_merge, |
1da177e4 LT |
1304 | }; |
1305 | ||
1306 | static int __init dm_crypt_init(void) | |
1307 | { | |
1308 | int r; | |
1309 | ||
028867ac | 1310 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1311 | if (!_crypt_io_pool) |
1312 | return -ENOMEM; | |
1313 | ||
1da177e4 LT |
1314 | r = dm_register_target(&crypt_target); |
1315 | if (r < 0) { | |
72d94861 | 1316 | DMERR("register failed %d", r); |
9934a8be | 1317 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1318 | } |
1319 | ||
1da177e4 LT |
1320 | return r; |
1321 | } | |
1322 | ||
1323 | static void __exit dm_crypt_exit(void) | |
1324 | { | |
1325 | int r = dm_unregister_target(&crypt_target); | |
1326 | ||
1327 | if (r < 0) | |
72d94861 | 1328 | DMERR("unregister failed %d", r); |
1da177e4 | 1329 | |
1da177e4 LT |
1330 | kmem_cache_destroy(_crypt_io_pool); |
1331 | } | |
1332 | ||
1333 | module_init(dm_crypt_init); | |
1334 | module_exit(dm_crypt_exit); | |
1335 | ||
1336 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1337 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1338 | MODULE_LICENSE("GPL"); |