Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
542da317 | 4 | * Copyright (C) 2006-2009 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
5 | * |
6 | * This file is released under the GPL. | |
7 | */ | |
8 | ||
43d69034 | 9 | #include <linux/completion.h> |
d1806f6a | 10 | #include <linux/err.h> |
1da177e4 LT |
11 | #include <linux/module.h> |
12 | #include <linux/init.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/bio.h> | |
15 | #include <linux/blkdev.h> | |
16 | #include <linux/mempool.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/crypto.h> | |
19 | #include <linux/workqueue.h> | |
3fcfab16 | 20 | #include <linux/backing-dev.h> |
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 | 62 | struct dm_crypt_request { |
b2174eeb | 63 | struct convert_context *ctx; |
01482b76 MB |
64 | struct scatterlist sg_in; |
65 | struct scatterlist sg_out; | |
66 | }; | |
67 | ||
1da177e4 LT |
68 | struct crypt_config; |
69 | ||
70 | struct crypt_iv_operations { | |
71 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 72 | const char *opts); |
1da177e4 | 73 | void (*dtr)(struct crypt_config *cc); |
b95bf2d3 | 74 | int (*init)(struct crypt_config *cc); |
542da317 | 75 | int (*wipe)(struct crypt_config *cc); |
1da177e4 LT |
76 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); |
77 | }; | |
78 | ||
60473592 MB |
79 | struct iv_essiv_private { |
80 | struct crypto_cipher *tfm; | |
b95bf2d3 MB |
81 | struct crypto_hash *hash_tfm; |
82 | u8 *salt; | |
60473592 MB |
83 | }; |
84 | ||
85 | struct iv_benbi_private { | |
86 | int shift; | |
87 | }; | |
88 | ||
1da177e4 LT |
89 | /* |
90 | * Crypt: maps a linear range of a block device | |
91 | * and encrypts / decrypts at the same time. | |
92 | */ | |
e48d4bbf | 93 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
94 | struct crypt_config { |
95 | struct dm_dev *dev; | |
96 | sector_t start; | |
97 | ||
98 | /* | |
ddd42edf MB |
99 | * pool for per bio private data, crypto requests and |
100 | * encryption requeusts/buffer pages | |
1da177e4 LT |
101 | */ |
102 | mempool_t *io_pool; | |
ddd42edf | 103 | mempool_t *req_pool; |
1da177e4 | 104 | mempool_t *page_pool; |
6a24c718 | 105 | struct bio_set *bs; |
1da177e4 | 106 | |
cabf08e4 MB |
107 | struct workqueue_struct *io_queue; |
108 | struct workqueue_struct *crypt_queue; | |
3f1e9070 | 109 | |
1da177e4 LT |
110 | /* |
111 | * crypto related data | |
112 | */ | |
113 | struct crypt_iv_operations *iv_gen_ops; | |
114 | char *iv_mode; | |
79066ad3 | 115 | union { |
60473592 MB |
116 | struct iv_essiv_private essiv; |
117 | struct iv_benbi_private benbi; | |
79066ad3 | 118 | } iv_gen_private; |
1da177e4 LT |
119 | sector_t iv_offset; |
120 | unsigned int iv_size; | |
121 | ||
ddd42edf MB |
122 | /* |
123 | * Layout of each crypto request: | |
124 | * | |
125 | * struct ablkcipher_request | |
126 | * context | |
127 | * padding | |
128 | * struct dm_crypt_request | |
129 | * padding | |
130 | * IV | |
131 | * | |
132 | * The padding is added so that dm_crypt_request and the IV are | |
133 | * correctly aligned. | |
134 | */ | |
135 | unsigned int dmreq_start; | |
136 | struct ablkcipher_request *req; | |
137 | ||
d1806f6a HX |
138 | char cipher[CRYPTO_MAX_ALG_NAME]; |
139 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
3a7f6c99 | 140 | struct crypto_ablkcipher *tfm; |
e48d4bbf | 141 | unsigned long flags; |
1da177e4 LT |
142 | unsigned int key_size; |
143 | u8 key[0]; | |
144 | }; | |
145 | ||
6a24c718 | 146 | #define MIN_IOS 16 |
1da177e4 LT |
147 | #define MIN_POOL_PAGES 32 |
148 | #define MIN_BIO_PAGES 8 | |
149 | ||
e18b890b | 150 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 151 | |
028867ac | 152 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 153 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 154 | |
1da177e4 LT |
155 | /* |
156 | * Different IV generation algorithms: | |
157 | * | |
3c164bd8 | 158 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 159 | * number, padded with zeros if necessary. |
1da177e4 | 160 | * |
61afef61 MB |
161 | * plain64: the initial vector is the 64-bit little-endian version of the sector |
162 | * number, padded with zeros if necessary. | |
163 | * | |
3c164bd8 RS |
164 | * essiv: "encrypted sector|salt initial vector", the sector number is |
165 | * encrypted with the bulk cipher using a salt as key. The salt | |
166 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 167 | * |
48527fa7 RS |
168 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
169 | * (needed for LRW-32-AES and possible other narrow block modes) | |
170 | * | |
46b47730 LN |
171 | * null: the initial vector is always zero. Provides compatibility with |
172 | * obsolete loop_fish2 devices. Do not use for new devices. | |
173 | * | |
1da177e4 LT |
174 | * plumb: unimplemented, see: |
175 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
176 | */ | |
177 | ||
178 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
179 | { | |
180 | memset(iv, 0, cc->iv_size); | |
181 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
182 | ||
183 | return 0; | |
184 | } | |
185 | ||
61afef61 MB |
186 | static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, |
187 | sector_t sector) | |
188 | { | |
189 | memset(iv, 0, cc->iv_size); | |
190 | *(u64 *)iv = cpu_to_le64(sector); | |
191 | ||
192 | return 0; | |
193 | } | |
194 | ||
b95bf2d3 MB |
195 | /* Initialise ESSIV - compute salt but no local memory allocations */ |
196 | static int crypt_iv_essiv_init(struct crypt_config *cc) | |
197 | { | |
198 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
199 | struct hash_desc desc; | |
200 | struct scatterlist sg; | |
201 | int err; | |
202 | ||
203 | sg_init_one(&sg, cc->key, cc->key_size); | |
204 | desc.tfm = essiv->hash_tfm; | |
205 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
206 | ||
207 | err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt); | |
208 | if (err) | |
209 | return err; | |
210 | ||
211 | return crypto_cipher_setkey(essiv->tfm, essiv->salt, | |
212 | crypto_hash_digestsize(essiv->hash_tfm)); | |
213 | } | |
214 | ||
542da317 MB |
215 | /* Wipe salt and reset key derived from volume key */ |
216 | static int crypt_iv_essiv_wipe(struct crypt_config *cc) | |
217 | { | |
218 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
219 | unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm); | |
220 | ||
221 | memset(essiv->salt, 0, salt_size); | |
222 | ||
223 | return crypto_cipher_setkey(essiv->tfm, essiv->salt, salt_size); | |
224 | } | |
225 | ||
60473592 MB |
226 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) |
227 | { | |
228 | struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv; | |
229 | ||
230 | crypto_free_cipher(essiv->tfm); | |
231 | essiv->tfm = NULL; | |
b95bf2d3 MB |
232 | |
233 | crypto_free_hash(essiv->hash_tfm); | |
234 | essiv->hash_tfm = NULL; | |
235 | ||
236 | kzfree(essiv->salt); | |
237 | essiv->salt = NULL; | |
60473592 MB |
238 | } |
239 | ||
1da177e4 | 240 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, |
d469f841 | 241 | const char *opts) |
1da177e4 | 242 | { |
5861f1be MB |
243 | struct crypto_cipher *essiv_tfm = NULL; |
244 | struct crypto_hash *hash_tfm = NULL; | |
5861f1be | 245 | u8 *salt = NULL; |
d1806f6a | 246 | int err; |
1da177e4 | 247 | |
5861f1be | 248 | if (!opts) { |
72d94861 | 249 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
250 | return -EINVAL; |
251 | } | |
252 | ||
b95bf2d3 | 253 | /* Allocate hash algorithm */ |
35058687 HX |
254 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
255 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 256 | ti->error = "Error initializing ESSIV hash"; |
5861f1be MB |
257 | err = PTR_ERR(hash_tfm); |
258 | goto bad; | |
1da177e4 LT |
259 | } |
260 | ||
b95bf2d3 | 261 | salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL); |
5861f1be | 262 | if (!salt) { |
72d94861 | 263 | ti->error = "Error kmallocing salt storage in ESSIV"; |
5861f1be MB |
264 | err = -ENOMEM; |
265 | goto bad; | |
1da177e4 LT |
266 | } |
267 | ||
b95bf2d3 | 268 | /* Allocate essiv_tfm */ |
d1806f6a HX |
269 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
270 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 271 | ti->error = "Error allocating crypto tfm for ESSIV"; |
5861f1be MB |
272 | err = PTR_ERR(essiv_tfm); |
273 | goto bad; | |
1da177e4 | 274 | } |
d1806f6a | 275 | if (crypto_cipher_blocksize(essiv_tfm) != |
3a7f6c99 | 276 | crypto_ablkcipher_ivsize(cc->tfm)) { |
72d94861 | 277 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 278 | "not match IV size of block cipher"; |
5861f1be MB |
279 | err = -EINVAL; |
280 | goto bad; | |
1da177e4 | 281 | } |
1da177e4 | 282 | |
b95bf2d3 | 283 | cc->iv_gen_private.essiv.salt = salt; |
60473592 | 284 | cc->iv_gen_private.essiv.tfm = essiv_tfm; |
b95bf2d3 MB |
285 | cc->iv_gen_private.essiv.hash_tfm = hash_tfm; |
286 | ||
1da177e4 | 287 | return 0; |
5861f1be MB |
288 | |
289 | bad: | |
290 | if (essiv_tfm && !IS_ERR(essiv_tfm)) | |
291 | crypto_free_cipher(essiv_tfm); | |
292 | if (hash_tfm && !IS_ERR(hash_tfm)) | |
293 | crypto_free_hash(hash_tfm); | |
b95bf2d3 | 294 | kfree(salt); |
5861f1be | 295 | return err; |
1da177e4 LT |
296 | } |
297 | ||
1da177e4 LT |
298 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
299 | { | |
1da177e4 LT |
300 | memset(iv, 0, cc->iv_size); |
301 | *(u64 *)iv = cpu_to_le64(sector); | |
60473592 | 302 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv.tfm, iv, iv); |
1da177e4 LT |
303 | return 0; |
304 | } | |
305 | ||
48527fa7 RS |
306 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
307 | const char *opts) | |
308 | { | |
3a7f6c99 | 309 | unsigned bs = crypto_ablkcipher_blocksize(cc->tfm); |
f0d1b0b3 | 310 | int log = ilog2(bs); |
48527fa7 RS |
311 | |
312 | /* we need to calculate how far we must shift the sector count | |
313 | * to get the cipher block count, we use this shift in _gen */ | |
314 | ||
315 | if (1 << log != bs) { | |
316 | ti->error = "cypher blocksize is not a power of 2"; | |
317 | return -EINVAL; | |
318 | } | |
319 | ||
320 | if (log > 9) { | |
321 | ti->error = "cypher blocksize is > 512"; | |
322 | return -EINVAL; | |
323 | } | |
324 | ||
60473592 | 325 | cc->iv_gen_private.benbi.shift = 9 - log; |
48527fa7 RS |
326 | |
327 | return 0; | |
328 | } | |
329 | ||
330 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
331 | { | |
48527fa7 RS |
332 | } |
333 | ||
334 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
335 | { | |
79066ad3 HX |
336 | __be64 val; |
337 | ||
48527fa7 | 338 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 | 339 | |
60473592 | 340 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi.shift) + 1); |
79066ad3 | 341 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); |
48527fa7 | 342 | |
1da177e4 LT |
343 | return 0; |
344 | } | |
345 | ||
46b47730 LN |
346 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
347 | { | |
348 | memset(iv, 0, cc->iv_size); | |
349 | ||
350 | return 0; | |
351 | } | |
352 | ||
1da177e4 LT |
353 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
354 | .generator = crypt_iv_plain_gen | |
355 | }; | |
356 | ||
61afef61 MB |
357 | static struct crypt_iv_operations crypt_iv_plain64_ops = { |
358 | .generator = crypt_iv_plain64_gen | |
359 | }; | |
360 | ||
1da177e4 LT |
361 | static struct crypt_iv_operations crypt_iv_essiv_ops = { |
362 | .ctr = crypt_iv_essiv_ctr, | |
363 | .dtr = crypt_iv_essiv_dtr, | |
b95bf2d3 | 364 | .init = crypt_iv_essiv_init, |
542da317 | 365 | .wipe = crypt_iv_essiv_wipe, |
1da177e4 LT |
366 | .generator = crypt_iv_essiv_gen |
367 | }; | |
368 | ||
48527fa7 RS |
369 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
370 | .ctr = crypt_iv_benbi_ctr, | |
371 | .dtr = crypt_iv_benbi_dtr, | |
372 | .generator = crypt_iv_benbi_gen | |
373 | }; | |
1da177e4 | 374 | |
46b47730 LN |
375 | static struct crypt_iv_operations crypt_iv_null_ops = { |
376 | .generator = crypt_iv_null_gen | |
377 | }; | |
378 | ||
d469f841 MB |
379 | static void crypt_convert_init(struct crypt_config *cc, |
380 | struct convert_context *ctx, | |
381 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 382 | sector_t sector) |
1da177e4 LT |
383 | { |
384 | ctx->bio_in = bio_in; | |
385 | ctx->bio_out = bio_out; | |
386 | ctx->offset_in = 0; | |
387 | ctx->offset_out = 0; | |
388 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
389 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
390 | ctx->sector = sector + cc->iv_offset; | |
43d69034 | 391 | init_completion(&ctx->restart); |
1da177e4 LT |
392 | } |
393 | ||
b2174eeb HY |
394 | static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, |
395 | struct ablkcipher_request *req) | |
396 | { | |
397 | return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
398 | } | |
399 | ||
400 | static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc, | |
401 | struct dm_crypt_request *dmreq) | |
402 | { | |
403 | return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start); | |
404 | } | |
405 | ||
01482b76 | 406 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
407 | struct convert_context *ctx, |
408 | struct ablkcipher_request *req) | |
01482b76 MB |
409 | { |
410 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
411 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
3a7f6c99 MB |
412 | struct dm_crypt_request *dmreq; |
413 | u8 *iv; | |
414 | int r = 0; | |
415 | ||
b2174eeb | 416 | dmreq = dmreq_of_req(cc, req); |
3a7f6c99 MB |
417 | iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), |
418 | crypto_ablkcipher_alignmask(cc->tfm) + 1); | |
01482b76 | 419 | |
b2174eeb | 420 | dmreq->ctx = ctx; |
3a7f6c99 MB |
421 | sg_init_table(&dmreq->sg_in, 1); |
422 | sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
423 | bv_in->bv_offset + ctx->offset_in); |
424 | ||
3a7f6c99 MB |
425 | sg_init_table(&dmreq->sg_out, 1); |
426 | sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
427 | bv_out->bv_offset + ctx->offset_out); |
428 | ||
429 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
430 | if (ctx->offset_in >= bv_in->bv_len) { | |
431 | ctx->offset_in = 0; | |
432 | ctx->idx_in++; | |
433 | } | |
434 | ||
435 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
436 | if (ctx->offset_out >= bv_out->bv_len) { | |
437 | ctx->offset_out = 0; | |
438 | ctx->idx_out++; | |
439 | } | |
440 | ||
3a7f6c99 MB |
441 | if (cc->iv_gen_ops) { |
442 | r = cc->iv_gen_ops->generator(cc, iv, ctx->sector); | |
443 | if (r < 0) | |
444 | return r; | |
445 | } | |
446 | ||
447 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
448 | 1 << SECTOR_SHIFT, iv); | |
449 | ||
450 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
451 | r = crypto_ablkcipher_encrypt(req); | |
452 | else | |
453 | r = crypto_ablkcipher_decrypt(req); | |
454 | ||
455 | return r; | |
01482b76 MB |
456 | } |
457 | ||
95497a96 MB |
458 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
459 | int error); | |
ddd42edf MB |
460 | static void crypt_alloc_req(struct crypt_config *cc, |
461 | struct convert_context *ctx) | |
462 | { | |
463 | if (!cc->req) | |
464 | cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
95497a96 MB |
465 | ablkcipher_request_set_tfm(cc->req, cc->tfm); |
466 | ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | | |
b2174eeb HY |
467 | CRYPTO_TFM_REQ_MAY_SLEEP, |
468 | kcryptd_async_done, | |
469 | dmreq_of_req(cc, cc->req)); | |
ddd42edf MB |
470 | } |
471 | ||
1da177e4 LT |
472 | /* |
473 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
474 | */ | |
475 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 476 | struct convert_context *ctx) |
1da177e4 | 477 | { |
3f1e9070 | 478 | int r; |
1da177e4 | 479 | |
c8081618 MB |
480 | atomic_set(&ctx->pending, 1); |
481 | ||
1da177e4 LT |
482 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && |
483 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
1da177e4 | 484 | |
3a7f6c99 MB |
485 | crypt_alloc_req(cc, ctx); |
486 | ||
3f1e9070 MB |
487 | atomic_inc(&ctx->pending); |
488 | ||
3a7f6c99 MB |
489 | r = crypt_convert_block(cc, ctx, cc->req); |
490 | ||
491 | switch (r) { | |
3f1e9070 | 492 | /* async */ |
3a7f6c99 MB |
493 | case -EBUSY: |
494 | wait_for_completion(&ctx->restart); | |
495 | INIT_COMPLETION(ctx->restart); | |
496 | /* fall through*/ | |
497 | case -EINPROGRESS: | |
3a7f6c99 | 498 | cc->req = NULL; |
3f1e9070 MB |
499 | ctx->sector++; |
500 | continue; | |
501 | ||
502 | /* sync */ | |
3a7f6c99 | 503 | case 0: |
3f1e9070 | 504 | atomic_dec(&ctx->pending); |
3a7f6c99 | 505 | ctx->sector++; |
c7f1b204 | 506 | cond_resched(); |
3a7f6c99 | 507 | continue; |
3a7f6c99 | 508 | |
3f1e9070 MB |
509 | /* error */ |
510 | default: | |
511 | atomic_dec(&ctx->pending); | |
512 | return r; | |
513 | } | |
1da177e4 LT |
514 | } |
515 | ||
3f1e9070 | 516 | return 0; |
1da177e4 LT |
517 | } |
518 | ||
d469f841 MB |
519 | static void dm_crypt_bio_destructor(struct bio *bio) |
520 | { | |
028867ac | 521 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
522 | struct crypt_config *cc = io->target->private; |
523 | ||
524 | bio_free(bio, cc->bs); | |
d469f841 | 525 | } |
6a24c718 | 526 | |
1da177e4 LT |
527 | /* |
528 | * Generate a new unfragmented bio with the given size | |
529 | * This should never violate the device limitations | |
933f01d4 MB |
530 | * May return a smaller bio when running out of pages, indicated by |
531 | * *out_of_pages set to 1. | |
1da177e4 | 532 | */ |
933f01d4 MB |
533 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size, |
534 | unsigned *out_of_pages) | |
1da177e4 | 535 | { |
027581f3 | 536 | struct crypt_config *cc = io->target->private; |
8b004457 | 537 | struct bio *clone; |
1da177e4 | 538 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 539 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
540 | unsigned i, len; |
541 | struct page *page; | |
1da177e4 | 542 | |
2f9941b6 | 543 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 544 | if (!clone) |
1da177e4 | 545 | return NULL; |
1da177e4 | 546 | |
027581f3 | 547 | clone_init(io, clone); |
933f01d4 | 548 | *out_of_pages = 0; |
6a24c718 | 549 | |
f97380bc | 550 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 | 551 | page = mempool_alloc(cc->page_pool, gfp_mask); |
933f01d4 MB |
552 | if (!page) { |
553 | *out_of_pages = 1; | |
1da177e4 | 554 | break; |
933f01d4 | 555 | } |
1da177e4 LT |
556 | |
557 | /* | |
558 | * if additional pages cannot be allocated without waiting, | |
559 | * return a partially allocated bio, the caller will then try | |
560 | * to allocate additional bios while submitting this partial bio | |
561 | */ | |
f97380bc | 562 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
563 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
564 | ||
91e10625 MB |
565 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
566 | ||
567 | if (!bio_add_page(clone, page, len, 0)) { | |
568 | mempool_free(page, cc->page_pool); | |
569 | break; | |
570 | } | |
1da177e4 | 571 | |
91e10625 | 572 | size -= len; |
1da177e4 LT |
573 | } |
574 | ||
8b004457 MB |
575 | if (!clone->bi_size) { |
576 | bio_put(clone); | |
1da177e4 LT |
577 | return NULL; |
578 | } | |
579 | ||
8b004457 | 580 | return clone; |
1da177e4 LT |
581 | } |
582 | ||
644bd2f0 | 583 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 584 | { |
644bd2f0 | 585 | unsigned int i; |
1da177e4 LT |
586 | struct bio_vec *bv; |
587 | ||
644bd2f0 | 588 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 589 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
590 | BUG_ON(!bv->bv_page); |
591 | mempool_free(bv->bv_page, cc->page_pool); | |
592 | bv->bv_page = NULL; | |
593 | } | |
594 | } | |
595 | ||
dc440d1e MB |
596 | static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti, |
597 | struct bio *bio, sector_t sector) | |
598 | { | |
599 | struct crypt_config *cc = ti->private; | |
600 | struct dm_crypt_io *io; | |
601 | ||
602 | io = mempool_alloc(cc->io_pool, GFP_NOIO); | |
603 | io->target = ti; | |
604 | io->base_bio = bio; | |
605 | io->sector = sector; | |
606 | io->error = 0; | |
393b47ef | 607 | io->base_io = NULL; |
dc440d1e MB |
608 | atomic_set(&io->pending, 0); |
609 | ||
610 | return io; | |
611 | } | |
612 | ||
3e1a8bdd MB |
613 | static void crypt_inc_pending(struct dm_crypt_io *io) |
614 | { | |
615 | atomic_inc(&io->pending); | |
616 | } | |
617 | ||
1da177e4 LT |
618 | /* |
619 | * One of the bios was finished. Check for completion of | |
620 | * the whole request and correctly clean up the buffer. | |
393b47ef | 621 | * If base_io is set, wait for the last fragment to complete. |
1da177e4 | 622 | */ |
5742fd77 | 623 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 624 | { |
5742fd77 | 625 | struct crypt_config *cc = io->target->private; |
b35f8caa MB |
626 | struct bio *base_bio = io->base_bio; |
627 | struct dm_crypt_io *base_io = io->base_io; | |
628 | int error = io->error; | |
1da177e4 LT |
629 | |
630 | if (!atomic_dec_and_test(&io->pending)) | |
631 | return; | |
632 | ||
b35f8caa MB |
633 | mempool_free(io, cc->io_pool); |
634 | ||
635 | if (likely(!base_io)) | |
636 | bio_endio(base_bio, error); | |
393b47ef | 637 | else { |
b35f8caa MB |
638 | if (error && !base_io->error) |
639 | base_io->error = error; | |
640 | crypt_dec_pending(base_io); | |
393b47ef | 641 | } |
1da177e4 LT |
642 | } |
643 | ||
644 | /* | |
cabf08e4 | 645 | * kcryptd/kcryptd_io: |
1da177e4 LT |
646 | * |
647 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 648 | * interrupt context. |
cabf08e4 MB |
649 | * |
650 | * kcryptd performs the actual encryption or decryption. | |
651 | * | |
652 | * kcryptd_io performs the IO submission. | |
653 | * | |
654 | * They must be separated as otherwise the final stages could be | |
655 | * starved by new requests which can block in the first stages due | |
656 | * to memory allocation. | |
1da177e4 | 657 | */ |
6712ecf8 | 658 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 659 | { |
028867ac | 660 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 661 | struct crypt_config *cc = io->target->private; |
ee7a491e | 662 | unsigned rw = bio_data_dir(clone); |
8b004457 | 663 | |
adfe4770 MB |
664 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
665 | error = -EIO; | |
666 | ||
8b004457 | 667 | /* |
6712ecf8 | 668 | * free the processed pages |
8b004457 | 669 | */ |
ee7a491e | 670 | if (rw == WRITE) |
644bd2f0 | 671 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
672 | |
673 | bio_put(clone); | |
8b004457 | 674 | |
ee7a491e MB |
675 | if (rw == READ && !error) { |
676 | kcryptd_queue_crypt(io); | |
677 | return; | |
678 | } | |
5742fd77 MB |
679 | |
680 | if (unlikely(error)) | |
681 | io->error = error; | |
682 | ||
683 | crypt_dec_pending(io); | |
8b004457 MB |
684 | } |
685 | ||
028867ac | 686 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
687 | { |
688 | struct crypt_config *cc = io->target->private; | |
689 | ||
690 | clone->bi_private = io; | |
691 | clone->bi_end_io = crypt_endio; | |
692 | clone->bi_bdev = cc->dev->bdev; | |
693 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 694 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
695 | } |
696 | ||
4e4eef64 | 697 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
698 | { |
699 | struct crypt_config *cc = io->target->private; | |
700 | struct bio *base_bio = io->base_bio; | |
701 | struct bio *clone; | |
93e605c2 | 702 | |
3e1a8bdd | 703 | crypt_inc_pending(io); |
8b004457 MB |
704 | |
705 | /* | |
706 | * The block layer might modify the bvec array, so always | |
707 | * copy the required bvecs because we need the original | |
708 | * one in order to decrypt the whole bio data *afterwards*. | |
709 | */ | |
6a24c718 | 710 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 711 | if (unlikely(!clone)) { |
5742fd77 MB |
712 | io->error = -ENOMEM; |
713 | crypt_dec_pending(io); | |
23541d2d | 714 | return; |
93e605c2 | 715 | } |
8b004457 MB |
716 | |
717 | clone_init(io, clone); | |
718 | clone->bi_idx = 0; | |
719 | clone->bi_vcnt = bio_segments(base_bio); | |
720 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 721 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
722 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
723 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 724 | |
93e605c2 | 725 | generic_make_request(clone); |
8b004457 MB |
726 | } |
727 | ||
4e4eef64 MB |
728 | static void kcryptd_io_write(struct dm_crypt_io *io) |
729 | { | |
95497a96 | 730 | struct bio *clone = io->ctx.bio_out; |
95497a96 | 731 | generic_make_request(clone); |
4e4eef64 MB |
732 | } |
733 | ||
395b167c AK |
734 | static void kcryptd_io(struct work_struct *work) |
735 | { | |
736 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
737 | ||
738 | if (bio_data_dir(io->base_bio) == READ) | |
739 | kcryptd_io_read(io); | |
740 | else | |
741 | kcryptd_io_write(io); | |
742 | } | |
743 | ||
744 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
745 | { | |
746 | struct crypt_config *cc = io->target->private; | |
747 | ||
748 | INIT_WORK(&io->work, kcryptd_io); | |
749 | queue_work(cc->io_queue, &io->work); | |
750 | } | |
751 | ||
95497a96 MB |
752 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
753 | int error, int async) | |
4e4eef64 | 754 | { |
dec1cedf MB |
755 | struct bio *clone = io->ctx.bio_out; |
756 | struct crypt_config *cc = io->target->private; | |
757 | ||
758 | if (unlikely(error < 0)) { | |
759 | crypt_free_buffer_pages(cc, clone); | |
760 | bio_put(clone); | |
761 | io->error = -EIO; | |
6c031f41 | 762 | crypt_dec_pending(io); |
dec1cedf MB |
763 | return; |
764 | } | |
765 | ||
766 | /* crypt_convert should have filled the clone bio */ | |
767 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
768 | ||
769 | clone->bi_sector = cc->start + io->sector; | |
899c95d3 | 770 | |
95497a96 MB |
771 | if (async) |
772 | kcryptd_queue_io(io); | |
1e37bb8e | 773 | else |
95497a96 | 774 | generic_make_request(clone); |
4e4eef64 MB |
775 | } |
776 | ||
fc5a5e9a | 777 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
8b004457 MB |
778 | { |
779 | struct crypt_config *cc = io->target->private; | |
8b004457 | 780 | struct bio *clone; |
393b47ef | 781 | struct dm_crypt_io *new_io; |
c8081618 | 782 | int crypt_finished; |
933f01d4 | 783 | unsigned out_of_pages = 0; |
dec1cedf | 784 | unsigned remaining = io->base_bio->bi_size; |
b635b00e | 785 | sector_t sector = io->sector; |
dec1cedf | 786 | int r; |
8b004457 | 787 | |
fc5a5e9a MB |
788 | /* |
789 | * Prevent io from disappearing until this function completes. | |
790 | */ | |
791 | crypt_inc_pending(io); | |
b635b00e | 792 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector); |
fc5a5e9a | 793 | |
93e605c2 MB |
794 | /* |
795 | * The allocated buffers can be smaller than the whole bio, | |
796 | * so repeat the whole process until all the data can be handled. | |
797 | */ | |
798 | while (remaining) { | |
933f01d4 | 799 | clone = crypt_alloc_buffer(io, remaining, &out_of_pages); |
23541d2d | 800 | if (unlikely(!clone)) { |
5742fd77 | 801 | io->error = -ENOMEM; |
fc5a5e9a | 802 | break; |
23541d2d | 803 | } |
93e605c2 | 804 | |
53017030 MB |
805 | io->ctx.bio_out = clone; |
806 | io->ctx.idx_out = 0; | |
93e605c2 | 807 | |
dec1cedf | 808 | remaining -= clone->bi_size; |
b635b00e | 809 | sector += bio_sectors(clone); |
93e605c2 | 810 | |
4e594098 | 811 | crypt_inc_pending(io); |
dec1cedf | 812 | r = crypt_convert(cc, &io->ctx); |
c8081618 | 813 | crypt_finished = atomic_dec_and_test(&io->ctx.pending); |
f97380bc | 814 | |
c8081618 MB |
815 | /* Encryption was already finished, submit io now */ |
816 | if (crypt_finished) { | |
3a7f6c99 | 817 | kcryptd_crypt_write_io_submit(io, r, 0); |
c8081618 MB |
818 | |
819 | /* | |
820 | * If there was an error, do not try next fragments. | |
821 | * For async, error is processed in async handler. | |
822 | */ | |
6c031f41 | 823 | if (unlikely(r < 0)) |
fc5a5e9a | 824 | break; |
b635b00e MB |
825 | |
826 | io->sector = sector; | |
4e594098 | 827 | } |
93e605c2 | 828 | |
933f01d4 MB |
829 | /* |
830 | * Out of memory -> run queues | |
831 | * But don't wait if split was due to the io size restriction | |
832 | */ | |
833 | if (unlikely(out_of_pages)) | |
8aa7e847 | 834 | congestion_wait(BLK_RW_ASYNC, HZ/100); |
933f01d4 | 835 | |
393b47ef MB |
836 | /* |
837 | * With async crypto it is unsafe to share the crypto context | |
838 | * between fragments, so switch to a new dm_crypt_io structure. | |
839 | */ | |
840 | if (unlikely(!crypt_finished && remaining)) { | |
841 | new_io = crypt_io_alloc(io->target, io->base_bio, | |
842 | sector); | |
843 | crypt_inc_pending(new_io); | |
844 | crypt_convert_init(cc, &new_io->ctx, NULL, | |
845 | io->base_bio, sector); | |
846 | new_io->ctx.idx_in = io->ctx.idx_in; | |
847 | new_io->ctx.offset_in = io->ctx.offset_in; | |
848 | ||
849 | /* | |
850 | * Fragments after the first use the base_io | |
851 | * pending count. | |
852 | */ | |
853 | if (!io->base_io) | |
854 | new_io->base_io = io; | |
855 | else { | |
856 | new_io->base_io = io->base_io; | |
857 | crypt_inc_pending(io->base_io); | |
858 | crypt_dec_pending(io); | |
859 | } | |
860 | ||
861 | io = new_io; | |
862 | } | |
93e605c2 | 863 | } |
899c95d3 MB |
864 | |
865 | crypt_dec_pending(io); | |
84131db6 MB |
866 | } |
867 | ||
4e4eef64 | 868 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
869 | { |
870 | if (unlikely(error < 0)) | |
871 | io->error = -EIO; | |
872 | ||
873 | crypt_dec_pending(io); | |
874 | } | |
875 | ||
4e4eef64 | 876 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
877 | { |
878 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 879 | int r = 0; |
1da177e4 | 880 | |
3e1a8bdd | 881 | crypt_inc_pending(io); |
3a7f6c99 | 882 | |
53017030 | 883 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 884 | io->sector); |
1da177e4 | 885 | |
5742fd77 MB |
886 | r = crypt_convert(cc, &io->ctx); |
887 | ||
3f1e9070 | 888 | if (atomic_dec_and_test(&io->ctx.pending)) |
3a7f6c99 MB |
889 | kcryptd_crypt_read_done(io, r); |
890 | ||
891 | crypt_dec_pending(io); | |
1da177e4 LT |
892 | } |
893 | ||
95497a96 MB |
894 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
895 | int error) | |
896 | { | |
b2174eeb HY |
897 | struct dm_crypt_request *dmreq = async_req->data; |
898 | struct convert_context *ctx = dmreq->ctx; | |
95497a96 MB |
899 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); |
900 | struct crypt_config *cc = io->target->private; | |
901 | ||
902 | if (error == -EINPROGRESS) { | |
903 | complete(&ctx->restart); | |
904 | return; | |
905 | } | |
906 | ||
b2174eeb | 907 | mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool); |
95497a96 MB |
908 | |
909 | if (!atomic_dec_and_test(&ctx->pending)) | |
910 | return; | |
911 | ||
912 | if (bio_data_dir(io->base_bio) == READ) | |
913 | kcryptd_crypt_read_done(io, error); | |
914 | else | |
915 | kcryptd_crypt_write_io_submit(io, error, 1); | |
916 | } | |
917 | ||
395b167c | 918 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 919 | { |
028867ac | 920 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 921 | |
cabf08e4 | 922 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 923 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 924 | else |
395b167c | 925 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
926 | } |
927 | ||
395b167c | 928 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 929 | { |
395b167c | 930 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 931 | |
395b167c AK |
932 | INIT_WORK(&io->work, kcryptd_crypt); |
933 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
934 | } |
935 | ||
936 | /* | |
937 | * Decode key from its hex representation | |
938 | */ | |
939 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
940 | { | |
941 | char buffer[3]; | |
942 | char *endp; | |
943 | unsigned int i; | |
944 | ||
945 | buffer[2] = '\0'; | |
946 | ||
8b004457 | 947 | for (i = 0; i < size; i++) { |
1da177e4 LT |
948 | buffer[0] = *hex++; |
949 | buffer[1] = *hex++; | |
950 | ||
951 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
952 | ||
953 | if (endp != &buffer[2]) | |
954 | return -EINVAL; | |
955 | } | |
956 | ||
957 | if (*hex != '\0') | |
958 | return -EINVAL; | |
959 | ||
960 | return 0; | |
961 | } | |
962 | ||
963 | /* | |
964 | * Encode key into its hex representation | |
965 | */ | |
966 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
967 | { | |
968 | unsigned int i; | |
969 | ||
8b004457 | 970 | for (i = 0; i < size; i++) { |
1da177e4 LT |
971 | sprintf(hex, "%02x", *key); |
972 | hex += 2; | |
973 | key++; | |
974 | } | |
975 | } | |
976 | ||
e48d4bbf MB |
977 | static int crypt_set_key(struct crypt_config *cc, char *key) |
978 | { | |
979 | unsigned key_size = strlen(key) >> 1; | |
980 | ||
981 | if (cc->key_size && cc->key_size != key_size) | |
982 | return -EINVAL; | |
983 | ||
984 | cc->key_size = key_size; /* initial settings */ | |
985 | ||
986 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 987 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
988 | return -EINVAL; |
989 | ||
990 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
991 | ||
0b430958 | 992 | return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size); |
e48d4bbf MB |
993 | } |
994 | ||
995 | static int crypt_wipe_key(struct crypt_config *cc) | |
996 | { | |
997 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
998 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
0b430958 | 999 | return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size); |
e48d4bbf MB |
1000 | } |
1001 | ||
1da177e4 LT |
1002 | /* |
1003 | * Construct an encryption mapping: | |
1004 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
1005 | */ | |
1006 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
1007 | { | |
1008 | struct crypt_config *cc; | |
3a7f6c99 | 1009 | struct crypto_ablkcipher *tfm; |
1da177e4 LT |
1010 | char *tmp; |
1011 | char *cipher; | |
1012 | char *chainmode; | |
1013 | char *ivmode; | |
1014 | char *ivopts; | |
1da177e4 | 1015 | unsigned int key_size; |
4ee218cd | 1016 | unsigned long long tmpll; |
1da177e4 LT |
1017 | |
1018 | if (argc != 5) { | |
72d94861 | 1019 | ti->error = "Not enough arguments"; |
1da177e4 LT |
1020 | return -EINVAL; |
1021 | } | |
1022 | ||
1023 | tmp = argv[0]; | |
1024 | cipher = strsep(&tmp, "-"); | |
1025 | chainmode = strsep(&tmp, "-"); | |
1026 | ivopts = strsep(&tmp, "-"); | |
1027 | ivmode = strsep(&ivopts, ":"); | |
1028 | ||
1029 | if (tmp) | |
72d94861 | 1030 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
1031 | |
1032 | key_size = strlen(argv[1]) >> 1; | |
1033 | ||
e48d4bbf | 1034 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
1035 | if (cc == NULL) { |
1036 | ti->error = | |
72d94861 | 1037 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
1038 | return -ENOMEM; |
1039 | } | |
1040 | ||
06fe9fb4 | 1041 | /* Compatibility mode for old dm-crypt cipher strings */ |
1da177e4 LT |
1042 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { |
1043 | chainmode = "cbc"; | |
1044 | ivmode = "plain"; | |
1045 | } | |
1046 | ||
d1806f6a HX |
1047 | if (strcmp(chainmode, "ecb") && !ivmode) { |
1048 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 1049 | goto bad_cipher; |
1da177e4 LT |
1050 | } |
1051 | ||
d469f841 MB |
1052 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
1053 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 1054 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 1055 | goto bad_cipher; |
1da177e4 LT |
1056 | } |
1057 | ||
3a7f6c99 | 1058 | tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0); |
d1806f6a | 1059 | if (IS_ERR(tfm)) { |
72d94861 | 1060 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 1061 | goto bad_cipher; |
1da177e4 | 1062 | } |
1da177e4 | 1063 | |
d1806f6a HX |
1064 | strcpy(cc->cipher, cipher); |
1065 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
1066 | cc->tfm = tfm; |
1067 | ||
0b430958 MB |
1068 | if (crypt_set_key(cc, argv[1]) < 0) { |
1069 | ti->error = "Error decoding and setting key"; | |
1070 | goto bad_ivmode; | |
1071 | } | |
1072 | ||
1da177e4 | 1073 | /* |
48527fa7 | 1074 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
1075 | * See comments at iv code |
1076 | */ | |
1077 | ||
1078 | if (ivmode == NULL) | |
1079 | cc->iv_gen_ops = NULL; | |
1080 | else if (strcmp(ivmode, "plain") == 0) | |
1081 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
61afef61 MB |
1082 | else if (strcmp(ivmode, "plain64") == 0) |
1083 | cc->iv_gen_ops = &crypt_iv_plain64_ops; | |
1da177e4 LT |
1084 | else if (strcmp(ivmode, "essiv") == 0) |
1085 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
1086 | else if (strcmp(ivmode, "benbi") == 0) |
1087 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
1088 | else if (strcmp(ivmode, "null") == 0) |
1089 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 1090 | else { |
72d94861 | 1091 | ti->error = "Invalid IV mode"; |
636d5786 | 1092 | goto bad_ivmode; |
1da177e4 LT |
1093 | } |
1094 | ||
1095 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
1096 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 1097 | goto bad_ivmode; |
1da177e4 | 1098 | |
b95bf2d3 MB |
1099 | if (cc->iv_gen_ops && cc->iv_gen_ops->init && |
1100 | cc->iv_gen_ops->init(cc) < 0) { | |
1101 | ti->error = "Error initialising IV"; | |
1102 | goto bad_slab_pool; | |
1103 | } | |
1104 | ||
3a7f6c99 | 1105 | cc->iv_size = crypto_ablkcipher_ivsize(tfm); |
d1806f6a | 1106 | if (cc->iv_size) |
1da177e4 | 1107 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 1108 | cc->iv_size = max(cc->iv_size, |
d469f841 | 1109 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 1110 | else { |
1da177e4 | 1111 | if (cc->iv_gen_ops) { |
72d94861 | 1112 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
1113 | if (cc->iv_gen_ops->dtr) |
1114 | cc->iv_gen_ops->dtr(cc); | |
1115 | cc->iv_gen_ops = NULL; | |
1116 | } | |
1117 | } | |
1118 | ||
93d2341c | 1119 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 1120 | if (!cc->io_pool) { |
72d94861 | 1121 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 1122 | goto bad_slab_pool; |
1da177e4 LT |
1123 | } |
1124 | ||
ddd42edf | 1125 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
3a7f6c99 | 1126 | cc->dmreq_start += crypto_ablkcipher_reqsize(tfm); |
ddd42edf | 1127 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); |
3a7f6c99 MB |
1128 | cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) & |
1129 | ~(crypto_tfm_ctx_alignment() - 1); | |
ddd42edf MB |
1130 | |
1131 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
1132 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
1133 | if (!cc->req_pool) { | |
1134 | ti->error = "Cannot allocate crypt request mempool"; | |
1135 | goto bad_req_pool; | |
1136 | } | |
1137 | cc->req = NULL; | |
1138 | ||
a19b27ce | 1139 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 1140 | if (!cc->page_pool) { |
72d94861 | 1141 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 1142 | goto bad_page_pool; |
1da177e4 LT |
1143 | } |
1144 | ||
bb799ca0 | 1145 | cc->bs = bioset_create(MIN_IOS, 0); |
6a24c718 MB |
1146 | if (!cc->bs) { |
1147 | ti->error = "Cannot allocate crypt bioset"; | |
1148 | goto bad_bs; | |
1149 | } | |
1150 | ||
4ee218cd | 1151 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 1152 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 1153 | goto bad_device; |
1da177e4 | 1154 | } |
4ee218cd | 1155 | cc->iv_offset = tmpll; |
1da177e4 | 1156 | |
4ee218cd | 1157 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1158 | ti->error = "Invalid device sector"; |
636d5786 | 1159 | goto bad_device; |
1da177e4 | 1160 | } |
4ee218cd | 1161 | cc->start = tmpll; |
1da177e4 LT |
1162 | |
1163 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 1164 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 1165 | ti->error = "Device lookup failed"; |
636d5786 | 1166 | goto bad_device; |
1da177e4 LT |
1167 | } |
1168 | ||
1169 | if (ivmode && cc->iv_gen_ops) { | |
1170 | if (ivopts) | |
1171 | *(ivopts - 1) = ':'; | |
1172 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
1173 | if (!cc->iv_mode) { | |
72d94861 | 1174 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 1175 | goto bad_ivmode_string; |
1da177e4 LT |
1176 | } |
1177 | strcpy(cc->iv_mode, ivmode); | |
1178 | } else | |
1179 | cc->iv_mode = NULL; | |
1180 | ||
cabf08e4 MB |
1181 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
1182 | if (!cc->io_queue) { | |
1183 | ti->error = "Couldn't create kcryptd io queue"; | |
1184 | goto bad_io_queue; | |
1185 | } | |
1186 | ||
1187 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
1188 | if (!cc->crypt_queue) { | |
9934a8be | 1189 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 1190 | goto bad_crypt_queue; |
9934a8be MB |
1191 | } |
1192 | ||
647c7db1 | 1193 | ti->num_flush_requests = 1; |
1da177e4 LT |
1194 | ti->private = cc; |
1195 | return 0; | |
1196 | ||
cabf08e4 MB |
1197 | bad_crypt_queue: |
1198 | destroy_workqueue(cc->io_queue); | |
1199 | bad_io_queue: | |
9934a8be | 1200 | kfree(cc->iv_mode); |
636d5786 | 1201 | bad_ivmode_string: |
55b42c5a | 1202 | dm_put_device(ti, cc->dev); |
636d5786 | 1203 | bad_device: |
6a24c718 MB |
1204 | bioset_free(cc->bs); |
1205 | bad_bs: | |
1da177e4 | 1206 | mempool_destroy(cc->page_pool); |
636d5786 | 1207 | bad_page_pool: |
ddd42edf MB |
1208 | mempool_destroy(cc->req_pool); |
1209 | bad_req_pool: | |
1da177e4 | 1210 | mempool_destroy(cc->io_pool); |
636d5786 | 1211 | bad_slab_pool: |
1da177e4 LT |
1212 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1213 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 1214 | bad_ivmode: |
3a7f6c99 | 1215 | crypto_free_ablkcipher(tfm); |
636d5786 | 1216 | bad_cipher: |
9d3520a3 | 1217 | /* Must zero key material before freeing */ |
b81d6cf7 | 1218 | kzfree(cc); |
1da177e4 LT |
1219 | return -EINVAL; |
1220 | } | |
1221 | ||
1222 | static void crypt_dtr(struct dm_target *ti) | |
1223 | { | |
1224 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1225 | ||
cabf08e4 MB |
1226 | destroy_workqueue(cc->io_queue); |
1227 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1228 | |
ddd42edf MB |
1229 | if (cc->req) |
1230 | mempool_free(cc->req, cc->req_pool); | |
1231 | ||
6a24c718 | 1232 | bioset_free(cc->bs); |
1da177e4 | 1233 | mempool_destroy(cc->page_pool); |
ddd42edf | 1234 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1235 | mempool_destroy(cc->io_pool); |
1236 | ||
990a8baf | 1237 | kfree(cc->iv_mode); |
1da177e4 LT |
1238 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1239 | cc->iv_gen_ops->dtr(cc); | |
3a7f6c99 | 1240 | crypto_free_ablkcipher(cc->tfm); |
1da177e4 | 1241 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1242 | |
1243 | /* Must zero key material before freeing */ | |
b81d6cf7 | 1244 | kzfree(cc); |
1da177e4 LT |
1245 | } |
1246 | ||
1da177e4 LT |
1247 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1248 | union map_info *map_context) | |
1249 | { | |
028867ac | 1250 | struct dm_crypt_io *io; |
647c7db1 MP |
1251 | struct crypt_config *cc; |
1252 | ||
1253 | if (unlikely(bio_empty_barrier(bio))) { | |
1254 | cc = ti->private; | |
1255 | bio->bi_bdev = cc->dev->bdev; | |
1256 | return DM_MAPIO_REMAPPED; | |
1257 | } | |
1da177e4 | 1258 | |
dc440d1e | 1259 | io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin); |
cabf08e4 MB |
1260 | |
1261 | if (bio_data_dir(io->base_bio) == READ) | |
1262 | kcryptd_queue_io(io); | |
1263 | else | |
1264 | kcryptd_queue_crypt(io); | |
1da177e4 | 1265 | |
d2a7ad29 | 1266 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1267 | } |
1268 | ||
1269 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1270 | char *result, unsigned int maxlen) | |
1271 | { | |
1272 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1273 | unsigned int sz = 0; |
1274 | ||
1275 | switch (type) { | |
1276 | case STATUSTYPE_INFO: | |
1277 | result[0] = '\0'; | |
1278 | break; | |
1279 | ||
1280 | case STATUSTYPE_TABLE: | |
1da177e4 | 1281 | if (cc->iv_mode) |
37af6560 CS |
1282 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1283 | cc->iv_mode); | |
1da177e4 | 1284 | else |
37af6560 | 1285 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1286 | |
1287 | if (cc->key_size > 0) { | |
1288 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1289 | return -ENOMEM; | |
1290 | ||
1291 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1292 | sz += cc->key_size << 1; | |
1293 | } else { | |
1294 | if (sz >= maxlen) | |
1295 | return -ENOMEM; | |
1296 | result[sz++] = '-'; | |
1297 | } | |
1298 | ||
4ee218cd AM |
1299 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1300 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1301 | break; |
1302 | } | |
1303 | return 0; | |
1304 | } | |
1305 | ||
e48d4bbf MB |
1306 | static void crypt_postsuspend(struct dm_target *ti) |
1307 | { | |
1308 | struct crypt_config *cc = ti->private; | |
1309 | ||
1310 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1311 | } | |
1312 | ||
1313 | static int crypt_preresume(struct dm_target *ti) | |
1314 | { | |
1315 | struct crypt_config *cc = ti->private; | |
1316 | ||
1317 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1318 | DMERR("aborting resume - crypt key is not set."); | |
1319 | return -EAGAIN; | |
1320 | } | |
1321 | ||
1322 | return 0; | |
1323 | } | |
1324 | ||
1325 | static void crypt_resume(struct dm_target *ti) | |
1326 | { | |
1327 | struct crypt_config *cc = ti->private; | |
1328 | ||
1329 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1330 | } | |
1331 | ||
1332 | /* Message interface | |
1333 | * key set <key> | |
1334 | * key wipe | |
1335 | */ | |
1336 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1337 | { | |
1338 | struct crypt_config *cc = ti->private; | |
542da317 | 1339 | int ret = -EINVAL; |
e48d4bbf MB |
1340 | |
1341 | if (argc < 2) | |
1342 | goto error; | |
1343 | ||
1344 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1345 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1346 | DMWARN("not suspended during key manipulation."); | |
1347 | return -EINVAL; | |
1348 | } | |
542da317 MB |
1349 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) { |
1350 | ret = crypt_set_key(cc, argv[2]); | |
1351 | if (ret) | |
1352 | return ret; | |
1353 | if (cc->iv_gen_ops && cc->iv_gen_ops->init) | |
1354 | ret = cc->iv_gen_ops->init(cc); | |
1355 | return ret; | |
1356 | } | |
1357 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) { | |
1358 | if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { | |
1359 | ret = cc->iv_gen_ops->wipe(cc); | |
1360 | if (ret) | |
1361 | return ret; | |
1362 | } | |
e48d4bbf | 1363 | return crypt_wipe_key(cc); |
542da317 | 1364 | } |
e48d4bbf MB |
1365 | } |
1366 | ||
1367 | error: | |
1368 | DMWARN("unrecognised message received."); | |
1369 | return -EINVAL; | |
1370 | } | |
1371 | ||
d41e26b9 MB |
1372 | static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
1373 | struct bio_vec *biovec, int max_size) | |
1374 | { | |
1375 | struct crypt_config *cc = ti->private; | |
1376 | struct request_queue *q = bdev_get_queue(cc->dev->bdev); | |
1377 | ||
1378 | if (!q->merge_bvec_fn) | |
1379 | return max_size; | |
1380 | ||
1381 | bvm->bi_bdev = cc->dev->bdev; | |
1382 | bvm->bi_sector = cc->start + bvm->bi_sector - ti->begin; | |
1383 | ||
1384 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); | |
1385 | } | |
1386 | ||
af4874e0 MS |
1387 | static int crypt_iterate_devices(struct dm_target *ti, |
1388 | iterate_devices_callout_fn fn, void *data) | |
1389 | { | |
1390 | struct crypt_config *cc = ti->private; | |
1391 | ||
5dea271b | 1392 | return fn(ti, cc->dev, cc->start, ti->len, data); |
af4874e0 MS |
1393 | } |
1394 | ||
1da177e4 LT |
1395 | static struct target_type crypt_target = { |
1396 | .name = "crypt", | |
af4874e0 | 1397 | .version = {1, 7, 0}, |
1da177e4 LT |
1398 | .module = THIS_MODULE, |
1399 | .ctr = crypt_ctr, | |
1400 | .dtr = crypt_dtr, | |
1401 | .map = crypt_map, | |
1402 | .status = crypt_status, | |
e48d4bbf MB |
1403 | .postsuspend = crypt_postsuspend, |
1404 | .preresume = crypt_preresume, | |
1405 | .resume = crypt_resume, | |
1406 | .message = crypt_message, | |
d41e26b9 | 1407 | .merge = crypt_merge, |
af4874e0 | 1408 | .iterate_devices = crypt_iterate_devices, |
1da177e4 LT |
1409 | }; |
1410 | ||
1411 | static int __init dm_crypt_init(void) | |
1412 | { | |
1413 | int r; | |
1414 | ||
028867ac | 1415 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1416 | if (!_crypt_io_pool) |
1417 | return -ENOMEM; | |
1418 | ||
1da177e4 LT |
1419 | r = dm_register_target(&crypt_target); |
1420 | if (r < 0) { | |
72d94861 | 1421 | DMERR("register failed %d", r); |
9934a8be | 1422 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1423 | } |
1424 | ||
1da177e4 LT |
1425 | return r; |
1426 | } | |
1427 | ||
1428 | static void __exit dm_crypt_exit(void) | |
1429 | { | |
10d3bd09 | 1430 | dm_unregister_target(&crypt_target); |
1da177e4 LT |
1431 | kmem_cache_destroy(_crypt_io_pool); |
1432 | } | |
1433 | ||
1434 | module_init(dm_crypt_init); | |
1435 | module_exit(dm_crypt_exit); | |
1436 | ||
1437 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1438 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1439 | MODULE_LICENSE("GPL"); |