Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
e48d4bbf | 4 | * Copyright (C) 2006 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
5 | * |
6 | * This file is released under the GPL. | |
7 | */ | |
8 | ||
d1806f6a | 9 | #include <linux/err.h> |
1da177e4 LT |
10 | #include <linux/module.h> |
11 | #include <linux/init.h> | |
12 | #include <linux/kernel.h> | |
13 | #include <linux/bio.h> | |
14 | #include <linux/blkdev.h> | |
15 | #include <linux/mempool.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/crypto.h> | |
18 | #include <linux/workqueue.h> | |
3fcfab16 | 19 | #include <linux/backing-dev.h> |
1da177e4 | 20 | #include <asm/atomic.h> |
378f058c | 21 | #include <linux/scatterlist.h> |
1da177e4 | 22 | #include <asm/page.h> |
48527fa7 | 23 | #include <asm/unaligned.h> |
1da177e4 LT |
24 | |
25 | #include "dm.h" | |
26 | ||
72d94861 | 27 | #define DM_MSG_PREFIX "crypt" |
e48d4bbf | 28 | #define MESG_STR(x) x, sizeof(x) |
1da177e4 LT |
29 | |
30 | /* | |
31 | * per bio private data | |
32 | */ | |
028867ac | 33 | struct dm_crypt_io { |
1da177e4 | 34 | struct dm_target *target; |
8b004457 | 35 | struct bio *base_bio; |
1da177e4 LT |
36 | struct work_struct work; |
37 | atomic_t pending; | |
38 | int error; | |
23541d2d | 39 | int post_process; |
1da177e4 LT |
40 | }; |
41 | ||
42 | /* | |
43 | * context holding the current state of a multi-part conversion | |
44 | */ | |
45 | struct convert_context { | |
46 | struct bio *bio_in; | |
47 | struct bio *bio_out; | |
48 | unsigned int offset_in; | |
49 | unsigned int offset_out; | |
50 | unsigned int idx_in; | |
51 | unsigned int idx_out; | |
52 | sector_t sector; | |
53 | int write; | |
54 | }; | |
55 | ||
56 | struct crypt_config; | |
57 | ||
58 | struct crypt_iv_operations { | |
59 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
60 | const char *opts); | |
61 | void (*dtr)(struct crypt_config *cc); | |
62 | const char *(*status)(struct crypt_config *cc); | |
63 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
64 | }; | |
65 | ||
66 | /* | |
67 | * Crypt: maps a linear range of a block device | |
68 | * and encrypts / decrypts at the same time. | |
69 | */ | |
e48d4bbf | 70 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
71 | struct crypt_config { |
72 | struct dm_dev *dev; | |
73 | sector_t start; | |
74 | ||
75 | /* | |
76 | * pool for per bio private data and | |
77 | * for encryption buffer pages | |
78 | */ | |
79 | mempool_t *io_pool; | |
80 | mempool_t *page_pool; | |
6a24c718 | 81 | struct bio_set *bs; |
1da177e4 | 82 | |
9934a8be | 83 | struct workqueue_struct *queue; |
1da177e4 LT |
84 | /* |
85 | * crypto related data | |
86 | */ | |
87 | struct crypt_iv_operations *iv_gen_ops; | |
88 | char *iv_mode; | |
79066ad3 HX |
89 | union { |
90 | struct crypto_cipher *essiv_tfm; | |
91 | int benbi_shift; | |
92 | } iv_gen_private; | |
1da177e4 LT |
93 | sector_t iv_offset; |
94 | unsigned int iv_size; | |
95 | ||
d1806f6a HX |
96 | char cipher[CRYPTO_MAX_ALG_NAME]; |
97 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
98 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 99 | unsigned long flags; |
1da177e4 LT |
100 | unsigned int key_size; |
101 | u8 key[0]; | |
102 | }; | |
103 | ||
6a24c718 | 104 | #define MIN_IOS 16 |
1da177e4 LT |
105 | #define MIN_POOL_PAGES 32 |
106 | #define MIN_BIO_PAGES 8 | |
107 | ||
e18b890b | 108 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 109 | |
028867ac | 110 | static void clone_init(struct dm_crypt_io *, struct bio *); |
027581f3 | 111 | |
1da177e4 LT |
112 | /* |
113 | * Different IV generation algorithms: | |
114 | * | |
3c164bd8 | 115 | * plain: the initial vector is the 32-bit little-endian version of the sector |
1da177e4 LT |
116 | * number, padded with zeros if neccessary. |
117 | * | |
3c164bd8 RS |
118 | * essiv: "encrypted sector|salt initial vector", the sector number is |
119 | * encrypted with the bulk cipher using a salt as key. The salt | |
120 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 121 | * |
48527fa7 RS |
122 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
123 | * (needed for LRW-32-AES and possible other narrow block modes) | |
124 | * | |
46b47730 LN |
125 | * null: the initial vector is always zero. Provides compatibility with |
126 | * obsolete loop_fish2 devices. Do not use for new devices. | |
127 | * | |
1da177e4 LT |
128 | * plumb: unimplemented, see: |
129 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
130 | */ | |
131 | ||
132 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
133 | { | |
134 | memset(iv, 0, cc->iv_size); | |
135 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
136 | ||
137 | return 0; | |
138 | } | |
139 | ||
140 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
141 | const char *opts) | |
142 | { | |
d1806f6a | 143 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
144 | struct crypto_hash *hash_tfm; |
145 | struct hash_desc desc; | |
1da177e4 LT |
146 | struct scatterlist sg; |
147 | unsigned int saltsize; | |
148 | u8 *salt; | |
d1806f6a | 149 | int err; |
1da177e4 LT |
150 | |
151 | if (opts == NULL) { | |
72d94861 | 152 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
153 | return -EINVAL; |
154 | } | |
155 | ||
156 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
157 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
158 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 159 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 160 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
161 | } |
162 | ||
35058687 | 163 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
164 | salt = kmalloc(saltsize, GFP_KERNEL); |
165 | if (salt == NULL) { | |
72d94861 | 166 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 167 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
168 | return -ENOMEM; |
169 | } | |
170 | ||
378f058c | 171 | sg_set_buf(&sg, cc->key, cc->key_size); |
35058687 HX |
172 | desc.tfm = hash_tfm; |
173 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
174 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
175 | crypto_free_hash(hash_tfm); | |
176 | ||
177 | if (err) { | |
178 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 179 | kfree(salt); |
35058687 HX |
180 | return err; |
181 | } | |
1da177e4 LT |
182 | |
183 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
184 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
185 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 186 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 187 | kfree(salt); |
d1806f6a | 188 | return PTR_ERR(essiv_tfm); |
1da177e4 | 189 | } |
d1806f6a HX |
190 | if (crypto_cipher_blocksize(essiv_tfm) != |
191 | crypto_blkcipher_ivsize(cc->tfm)) { | |
72d94861 | 192 | ti->error = "Block size of ESSIV cipher does " |
1da177e4 | 193 | "not match IV size of block cipher"; |
d1806f6a | 194 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
195 | kfree(salt); |
196 | return -EINVAL; | |
197 | } | |
d1806f6a HX |
198 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
199 | if (err) { | |
72d94861 | 200 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 201 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 202 | kfree(salt); |
d1806f6a | 203 | return err; |
1da177e4 LT |
204 | } |
205 | kfree(salt); | |
206 | ||
79066ad3 | 207 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
208 | return 0; |
209 | } | |
210 | ||
211 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
212 | { | |
79066ad3 HX |
213 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
214 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
215 | } |
216 | ||
217 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
218 | { | |
1da177e4 LT |
219 | memset(iv, 0, cc->iv_size); |
220 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 221 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
222 | return 0; |
223 | } | |
224 | ||
48527fa7 RS |
225 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
226 | const char *opts) | |
227 | { | |
228 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); | |
f0d1b0b3 | 229 | int log = ilog2(bs); |
48527fa7 RS |
230 | |
231 | /* we need to calculate how far we must shift the sector count | |
232 | * to get the cipher block count, we use this shift in _gen */ | |
233 | ||
234 | if (1 << log != bs) { | |
235 | ti->error = "cypher blocksize is not a power of 2"; | |
236 | return -EINVAL; | |
237 | } | |
238 | ||
239 | if (log > 9) { | |
240 | ti->error = "cypher blocksize is > 512"; | |
241 | return -EINVAL; | |
242 | } | |
243 | ||
79066ad3 | 244 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
245 | |
246 | return 0; | |
247 | } | |
248 | ||
249 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
250 | { | |
48527fa7 RS |
251 | } |
252 | ||
253 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
254 | { | |
79066ad3 HX |
255 | __be64 val; |
256 | ||
48527fa7 | 257 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
258 | |
259 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
260 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 261 | |
1da177e4 LT |
262 | return 0; |
263 | } | |
264 | ||
46b47730 LN |
265 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
266 | { | |
267 | memset(iv, 0, cc->iv_size); | |
268 | ||
269 | return 0; | |
270 | } | |
271 | ||
1da177e4 LT |
272 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
273 | .generator = crypt_iv_plain_gen | |
274 | }; | |
275 | ||
276 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
277 | .ctr = crypt_iv_essiv_ctr, | |
278 | .dtr = crypt_iv_essiv_dtr, | |
279 | .generator = crypt_iv_essiv_gen | |
280 | }; | |
281 | ||
48527fa7 RS |
282 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
283 | .ctr = crypt_iv_benbi_ctr, | |
284 | .dtr = crypt_iv_benbi_dtr, | |
285 | .generator = crypt_iv_benbi_gen | |
286 | }; | |
1da177e4 | 287 | |
46b47730 LN |
288 | static struct crypt_iv_operations crypt_iv_null_ops = { |
289 | .generator = crypt_iv_null_gen | |
290 | }; | |
291 | ||
858119e1 | 292 | static int |
1da177e4 LT |
293 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
294 | struct scatterlist *in, unsigned int length, | |
295 | int write, sector_t sector) | |
296 | { | |
45789328 | 297 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
d1806f6a HX |
298 | struct blkcipher_desc desc = { |
299 | .tfm = cc->tfm, | |
300 | .info = iv, | |
301 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, | |
302 | }; | |
1da177e4 LT |
303 | int r; |
304 | ||
305 | if (cc->iv_gen_ops) { | |
306 | r = cc->iv_gen_ops->generator(cc, iv, sector); | |
307 | if (r < 0) | |
308 | return r; | |
309 | ||
310 | if (write) | |
d1806f6a | 311 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
1da177e4 | 312 | else |
d1806f6a | 313 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
1da177e4 LT |
314 | } else { |
315 | if (write) | |
d1806f6a | 316 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
1da177e4 | 317 | else |
d1806f6a | 318 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
1da177e4 LT |
319 | } |
320 | ||
321 | return r; | |
322 | } | |
323 | ||
324 | static void | |
325 | crypt_convert_init(struct crypt_config *cc, struct convert_context *ctx, | |
326 | struct bio *bio_out, struct bio *bio_in, | |
327 | sector_t sector, int write) | |
328 | { | |
329 | ctx->bio_in = bio_in; | |
330 | ctx->bio_out = bio_out; | |
331 | ctx->offset_in = 0; | |
332 | ctx->offset_out = 0; | |
333 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
334 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
335 | ctx->sector = sector + cc->iv_offset; | |
336 | ctx->write = write; | |
337 | } | |
338 | ||
339 | /* | |
340 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
341 | */ | |
342 | static int crypt_convert(struct crypt_config *cc, | |
343 | struct convert_context *ctx) | |
344 | { | |
345 | int r = 0; | |
346 | ||
347 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
348 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
349 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
350 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
351 | struct scatterlist sg_in = { | |
352 | .page = bv_in->bv_page, | |
353 | .offset = bv_in->bv_offset + ctx->offset_in, | |
354 | .length = 1 << SECTOR_SHIFT | |
355 | }; | |
356 | struct scatterlist sg_out = { | |
357 | .page = bv_out->bv_page, | |
358 | .offset = bv_out->bv_offset + ctx->offset_out, | |
359 | .length = 1 << SECTOR_SHIFT | |
360 | }; | |
361 | ||
362 | ctx->offset_in += sg_in.length; | |
363 | if (ctx->offset_in >= bv_in->bv_len) { | |
364 | ctx->offset_in = 0; | |
365 | ctx->idx_in++; | |
366 | } | |
367 | ||
368 | ctx->offset_out += sg_out.length; | |
369 | if (ctx->offset_out >= bv_out->bv_len) { | |
370 | ctx->offset_out = 0; | |
371 | ctx->idx_out++; | |
372 | } | |
373 | ||
374 | r = crypt_convert_scatterlist(cc, &sg_out, &sg_in, sg_in.length, | |
375 | ctx->write, ctx->sector); | |
376 | if (r < 0) | |
377 | break; | |
378 | ||
379 | ctx->sector++; | |
380 | } | |
381 | ||
382 | return r; | |
383 | } | |
384 | ||
6a24c718 MB |
385 | static void dm_crypt_bio_destructor(struct bio *bio) |
386 | { | |
028867ac | 387 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
388 | struct crypt_config *cc = io->target->private; |
389 | ||
390 | bio_free(bio, cc->bs); | |
391 | } | |
392 | ||
1da177e4 LT |
393 | /* |
394 | * Generate a new unfragmented bio with the given size | |
395 | * This should never violate the device limitations | |
396 | * May return a smaller bio when running out of pages | |
397 | */ | |
028867ac | 398 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 399 | { |
027581f3 | 400 | struct crypt_config *cc = io->target->private; |
8b004457 | 401 | struct bio *clone; |
1da177e4 | 402 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 403 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
1da177e4 LT |
404 | unsigned int i; |
405 | ||
2f9941b6 | 406 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 407 | if (!clone) |
1da177e4 | 408 | return NULL; |
1da177e4 | 409 | |
027581f3 | 410 | clone_init(io, clone); |
6a24c718 | 411 | |
f97380bc | 412 | for (i = 0; i < nr_iovecs; i++) { |
8b004457 | 413 | struct bio_vec *bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
414 | |
415 | bv->bv_page = mempool_alloc(cc->page_pool, gfp_mask); | |
416 | if (!bv->bv_page) | |
417 | break; | |
418 | ||
419 | /* | |
420 | * if additional pages cannot be allocated without waiting, | |
421 | * return a partially allocated bio, the caller will then try | |
422 | * to allocate additional bios while submitting this partial bio | |
423 | */ | |
f97380bc | 424 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
425 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
426 | ||
427 | bv->bv_offset = 0; | |
428 | if (size > PAGE_SIZE) | |
429 | bv->bv_len = PAGE_SIZE; | |
430 | else | |
431 | bv->bv_len = size; | |
432 | ||
8b004457 MB |
433 | clone->bi_size += bv->bv_len; |
434 | clone->bi_vcnt++; | |
1da177e4 LT |
435 | size -= bv->bv_len; |
436 | } | |
437 | ||
8b004457 MB |
438 | if (!clone->bi_size) { |
439 | bio_put(clone); | |
1da177e4 LT |
440 | return NULL; |
441 | } | |
442 | ||
8b004457 | 443 | return clone; |
1da177e4 LT |
444 | } |
445 | ||
644bd2f0 | 446 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 447 | { |
644bd2f0 | 448 | unsigned int i; |
1da177e4 LT |
449 | struct bio_vec *bv; |
450 | ||
644bd2f0 | 451 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 452 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
453 | BUG_ON(!bv->bv_page); |
454 | mempool_free(bv->bv_page, cc->page_pool); | |
455 | bv->bv_page = NULL; | |
456 | } | |
457 | } | |
458 | ||
459 | /* | |
460 | * One of the bios was finished. Check for completion of | |
461 | * the whole request and correctly clean up the buffer. | |
462 | */ | |
028867ac | 463 | static void dec_pending(struct dm_crypt_io *io, int error) |
1da177e4 LT |
464 | { |
465 | struct crypt_config *cc = (struct crypt_config *) io->target->private; | |
466 | ||
467 | if (error < 0) | |
468 | io->error = error; | |
469 | ||
470 | if (!atomic_dec_and_test(&io->pending)) | |
471 | return; | |
472 | ||
6712ecf8 | 473 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
474 | |
475 | mempool_free(io, cc->io_pool); | |
476 | } | |
477 | ||
478 | /* | |
479 | * kcryptd: | |
480 | * | |
481 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 482 | * interrupt context. |
1da177e4 | 483 | */ |
c4028958 | 484 | static void kcryptd_do_work(struct work_struct *work); |
1da177e4 | 485 | |
028867ac | 486 | static void kcryptd_queue_io(struct dm_crypt_io *io) |
1da177e4 | 487 | { |
9934a8be MB |
488 | struct crypt_config *cc = io->target->private; |
489 | ||
c4028958 | 490 | INIT_WORK(&io->work, kcryptd_do_work); |
9934a8be | 491 | queue_work(cc->queue, &io->work); |
8b004457 MB |
492 | } |
493 | ||
6712ecf8 | 494 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 495 | { |
028867ac | 496 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 MB |
497 | struct crypt_config *cc = io->target->private; |
498 | unsigned read_io = bio_data_dir(clone) == READ; | |
499 | ||
500 | /* | |
6712ecf8 | 501 | * free the processed pages |
8b004457 | 502 | */ |
6712ecf8 | 503 | if (!read_io) { |
644bd2f0 | 504 | crypt_free_buffer_pages(cc, clone); |
8b004457 | 505 | goto out; |
6712ecf8 | 506 | } |
8b004457 MB |
507 | |
508 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE))) { | |
509 | error = -EIO; | |
510 | goto out; | |
511 | } | |
512 | ||
513 | bio_put(clone); | |
23541d2d | 514 | io->post_process = 1; |
8b004457 | 515 | kcryptd_queue_io(io); |
6712ecf8 | 516 | return; |
8b004457 MB |
517 | |
518 | out: | |
519 | bio_put(clone); | |
520 | dec_pending(io, error); | |
8b004457 MB |
521 | } |
522 | ||
028867ac | 523 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
524 | { |
525 | struct crypt_config *cc = io->target->private; | |
526 | ||
527 | clone->bi_private = io; | |
528 | clone->bi_end_io = crypt_endio; | |
529 | clone->bi_bdev = cc->dev->bdev; | |
530 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 531 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
532 | } |
533 | ||
028867ac | 534 | static void process_read(struct dm_crypt_io *io) |
8b004457 MB |
535 | { |
536 | struct crypt_config *cc = io->target->private; | |
537 | struct bio *base_bio = io->base_bio; | |
538 | struct bio *clone; | |
93e605c2 MB |
539 | sector_t sector = base_bio->bi_sector - io->target->begin; |
540 | ||
541 | atomic_inc(&io->pending); | |
8b004457 MB |
542 | |
543 | /* | |
544 | * The block layer might modify the bvec array, so always | |
545 | * copy the required bvecs because we need the original | |
546 | * one in order to decrypt the whole bio data *afterwards*. | |
547 | */ | |
6a24c718 | 548 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 MB |
549 | if (unlikely(!clone)) { |
550 | dec_pending(io, -ENOMEM); | |
23541d2d | 551 | return; |
93e605c2 | 552 | } |
8b004457 MB |
553 | |
554 | clone_init(io, clone); | |
555 | clone->bi_idx = 0; | |
556 | clone->bi_vcnt = bio_segments(base_bio); | |
557 | clone->bi_size = base_bio->bi_size; | |
93e605c2 | 558 | clone->bi_sector = cc->start + sector; |
8b004457 MB |
559 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
560 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 561 | |
93e605c2 | 562 | generic_make_request(clone); |
8b004457 MB |
563 | } |
564 | ||
028867ac | 565 | static void process_write(struct dm_crypt_io *io) |
8b004457 MB |
566 | { |
567 | struct crypt_config *cc = io->target->private; | |
568 | struct bio *base_bio = io->base_bio; | |
569 | struct bio *clone; | |
93e605c2 MB |
570 | struct convert_context ctx; |
571 | unsigned remaining = base_bio->bi_size; | |
572 | sector_t sector = base_bio->bi_sector - io->target->begin; | |
8b004457 | 573 | |
93e605c2 | 574 | atomic_inc(&io->pending); |
8b004457 | 575 | |
93e605c2 | 576 | crypt_convert_init(cc, &ctx, NULL, base_bio, sector, 1); |
8b004457 | 577 | |
93e605c2 MB |
578 | /* |
579 | * The allocated buffers can be smaller than the whole bio, | |
580 | * so repeat the whole process until all the data can be handled. | |
581 | */ | |
582 | while (remaining) { | |
f97380bc | 583 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d MB |
584 | if (unlikely(!clone)) { |
585 | dec_pending(io, -ENOMEM); | |
586 | return; | |
587 | } | |
93e605c2 MB |
588 | |
589 | ctx.bio_out = clone; | |
f97380bc | 590 | ctx.idx_out = 0; |
93e605c2 MB |
591 | |
592 | if (unlikely(crypt_convert(cc, &ctx) < 0)) { | |
644bd2f0 | 593 | crypt_free_buffer_pages(cc, clone); |
93e605c2 | 594 | bio_put(clone); |
23541d2d MB |
595 | dec_pending(io, -EIO); |
596 | return; | |
93e605c2 MB |
597 | } |
598 | ||
f97380bc OK |
599 | /* crypt_convert should have filled the clone bio */ |
600 | BUG_ON(ctx.idx_out < clone->bi_vcnt); | |
601 | ||
93e605c2 | 602 | clone->bi_sector = cc->start + sector; |
93e605c2 MB |
603 | remaining -= clone->bi_size; |
604 | sector += bio_sectors(clone); | |
605 | ||
2f9941b6 OK |
606 | /* Grab another reference to the io struct |
607 | * before we kick off the request */ | |
23541d2d MB |
608 | if (remaining) |
609 | atomic_inc(&io->pending); | |
610 | ||
93e605c2 MB |
611 | generic_make_request(clone); |
612 | ||
98221eb7 OK |
613 | /* Do not reference clone after this - it |
614 | * may be gone already. */ | |
615 | ||
93e605c2 MB |
616 | /* out of memory -> run queues */ |
617 | if (remaining) | |
98221eb7 | 618 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 619 | } |
8b004457 MB |
620 | } |
621 | ||
028867ac | 622 | static void process_read_endio(struct dm_crypt_io *io) |
8b004457 MB |
623 | { |
624 | struct crypt_config *cc = io->target->private; | |
1da177e4 | 625 | struct convert_context ctx; |
1da177e4 | 626 | |
8b004457 MB |
627 | crypt_convert_init(cc, &ctx, io->base_bio, io->base_bio, |
628 | io->base_bio->bi_sector - io->target->begin, 0); | |
1da177e4 | 629 | |
8b004457 | 630 | dec_pending(io, crypt_convert(cc, &ctx)); |
1da177e4 LT |
631 | } |
632 | ||
c4028958 | 633 | static void kcryptd_do_work(struct work_struct *work) |
1da177e4 | 634 | { |
028867ac | 635 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 636 | |
23541d2d MB |
637 | if (io->post_process) |
638 | process_read_endio(io); | |
639 | else if (bio_data_dir(io->base_bio) == READ) | |
640 | process_read(io); | |
641 | else | |
642 | process_write(io); | |
1da177e4 LT |
643 | } |
644 | ||
645 | /* | |
646 | * Decode key from its hex representation | |
647 | */ | |
648 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
649 | { | |
650 | char buffer[3]; | |
651 | char *endp; | |
652 | unsigned int i; | |
653 | ||
654 | buffer[2] = '\0'; | |
655 | ||
8b004457 | 656 | for (i = 0; i < size; i++) { |
1da177e4 LT |
657 | buffer[0] = *hex++; |
658 | buffer[1] = *hex++; | |
659 | ||
660 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
661 | ||
662 | if (endp != &buffer[2]) | |
663 | return -EINVAL; | |
664 | } | |
665 | ||
666 | if (*hex != '\0') | |
667 | return -EINVAL; | |
668 | ||
669 | return 0; | |
670 | } | |
671 | ||
672 | /* | |
673 | * Encode key into its hex representation | |
674 | */ | |
675 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
676 | { | |
677 | unsigned int i; | |
678 | ||
8b004457 | 679 | for (i = 0; i < size; i++) { |
1da177e4 LT |
680 | sprintf(hex, "%02x", *key); |
681 | hex += 2; | |
682 | key++; | |
683 | } | |
684 | } | |
685 | ||
e48d4bbf MB |
686 | static int crypt_set_key(struct crypt_config *cc, char *key) |
687 | { | |
688 | unsigned key_size = strlen(key) >> 1; | |
689 | ||
690 | if (cc->key_size && cc->key_size != key_size) | |
691 | return -EINVAL; | |
692 | ||
693 | cc->key_size = key_size; /* initial settings */ | |
694 | ||
695 | if ((!key_size && strcmp(key, "-")) || | |
696 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) | |
697 | return -EINVAL; | |
698 | ||
699 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
700 | ||
701 | return 0; | |
702 | } | |
703 | ||
704 | static int crypt_wipe_key(struct crypt_config *cc) | |
705 | { | |
706 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
707 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
708 | return 0; | |
709 | } | |
710 | ||
1da177e4 LT |
711 | /* |
712 | * Construct an encryption mapping: | |
713 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
714 | */ | |
715 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
716 | { | |
717 | struct crypt_config *cc; | |
d1806f6a | 718 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
719 | char *tmp; |
720 | char *cipher; | |
721 | char *chainmode; | |
722 | char *ivmode; | |
723 | char *ivopts; | |
1da177e4 | 724 | unsigned int key_size; |
4ee218cd | 725 | unsigned long long tmpll; |
1da177e4 LT |
726 | |
727 | if (argc != 5) { | |
72d94861 | 728 | ti->error = "Not enough arguments"; |
1da177e4 LT |
729 | return -EINVAL; |
730 | } | |
731 | ||
732 | tmp = argv[0]; | |
733 | cipher = strsep(&tmp, "-"); | |
734 | chainmode = strsep(&tmp, "-"); | |
735 | ivopts = strsep(&tmp, "-"); | |
736 | ivmode = strsep(&ivopts, ":"); | |
737 | ||
738 | if (tmp) | |
72d94861 | 739 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
740 | |
741 | key_size = strlen(argv[1]) >> 1; | |
742 | ||
e48d4bbf | 743 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
744 | if (cc == NULL) { |
745 | ti->error = | |
72d94861 | 746 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
747 | return -ENOMEM; |
748 | } | |
749 | ||
e48d4bbf | 750 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 751 | ti->error = "Error decoding key"; |
1da177e4 LT |
752 | goto bad1; |
753 | } | |
754 | ||
755 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
756 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
757 | chainmode = "cbc"; | |
758 | ivmode = "plain"; | |
759 | } | |
760 | ||
d1806f6a HX |
761 | if (strcmp(chainmode, "ecb") && !ivmode) { |
762 | ti->error = "This chaining mode requires an IV mechanism"; | |
1da177e4 LT |
763 | goto bad1; |
764 | } | |
765 | ||
d1806f6a HX |
766 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", chainmode, |
767 | cipher) >= CRYPTO_MAX_ALG_NAME) { | |
768 | ti->error = "Chain mode + cipher name is too long"; | |
1da177e4 LT |
769 | goto bad1; |
770 | } | |
771 | ||
d1806f6a HX |
772 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
773 | if (IS_ERR(tfm)) { | |
72d94861 | 774 | ti->error = "Error allocating crypto tfm"; |
1da177e4 LT |
775 | goto bad1; |
776 | } | |
1da177e4 | 777 | |
d1806f6a HX |
778 | strcpy(cc->cipher, cipher); |
779 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
780 | cc->tfm = tfm; |
781 | ||
782 | /* | |
48527fa7 | 783 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
784 | * See comments at iv code |
785 | */ | |
786 | ||
787 | if (ivmode == NULL) | |
788 | cc->iv_gen_ops = NULL; | |
789 | else if (strcmp(ivmode, "plain") == 0) | |
790 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
791 | else if (strcmp(ivmode, "essiv") == 0) | |
792 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
793 | else if (strcmp(ivmode, "benbi") == 0) |
794 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
795 | else if (strcmp(ivmode, "null") == 0) |
796 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 797 | else { |
72d94861 | 798 | ti->error = "Invalid IV mode"; |
1da177e4 LT |
799 | goto bad2; |
800 | } | |
801 | ||
802 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
803 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
804 | goto bad2; | |
805 | ||
d1806f6a HX |
806 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
807 | if (cc->iv_size) | |
1da177e4 | 808 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 809 | cc->iv_size = max(cc->iv_size, |
1da177e4 LT |
810 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
811 | else { | |
1da177e4 | 812 | if (cc->iv_gen_ops) { |
72d94861 | 813 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
814 | if (cc->iv_gen_ops->dtr) |
815 | cc->iv_gen_ops->dtr(cc); | |
816 | cc->iv_gen_ops = NULL; | |
817 | } | |
818 | } | |
819 | ||
93d2341c | 820 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 821 | if (!cc->io_pool) { |
72d94861 | 822 | ti->error = "Cannot allocate crypt io mempool"; |
1da177e4 LT |
823 | goto bad3; |
824 | } | |
825 | ||
a19b27ce | 826 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 827 | if (!cc->page_pool) { |
72d94861 | 828 | ti->error = "Cannot allocate page mempool"; |
1da177e4 LT |
829 | goto bad4; |
830 | } | |
831 | ||
5972511b | 832 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
833 | if (!cc->bs) { |
834 | ti->error = "Cannot allocate crypt bioset"; | |
835 | goto bad_bs; | |
836 | } | |
837 | ||
d1806f6a | 838 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 839 | ti->error = "Error setting key"; |
1da177e4 LT |
840 | goto bad5; |
841 | } | |
842 | ||
4ee218cd | 843 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 844 | ti->error = "Invalid iv_offset sector"; |
1da177e4 LT |
845 | goto bad5; |
846 | } | |
4ee218cd | 847 | cc->iv_offset = tmpll; |
1da177e4 | 848 | |
4ee218cd | 849 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 850 | ti->error = "Invalid device sector"; |
1da177e4 LT |
851 | goto bad5; |
852 | } | |
4ee218cd | 853 | cc->start = tmpll; |
1da177e4 LT |
854 | |
855 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
856 | dm_table_get_mode(ti->table), &cc->dev)) { | |
72d94861 | 857 | ti->error = "Device lookup failed"; |
1da177e4 LT |
858 | goto bad5; |
859 | } | |
860 | ||
861 | if (ivmode && cc->iv_gen_ops) { | |
862 | if (ivopts) | |
863 | *(ivopts - 1) = ':'; | |
864 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
865 | if (!cc->iv_mode) { | |
72d94861 | 866 | ti->error = "Error kmallocing iv_mode string"; |
55b42c5a | 867 | goto bad_iv_mode; |
1da177e4 LT |
868 | } |
869 | strcpy(cc->iv_mode, ivmode); | |
870 | } else | |
871 | cc->iv_mode = NULL; | |
872 | ||
9934a8be MB |
873 | cc->queue = create_singlethread_workqueue("kcryptd"); |
874 | if (!cc->queue) { | |
875 | ti->error = "Couldn't create kcryptd queue"; | |
876 | goto bad_queue; | |
877 | } | |
878 | ||
1da177e4 LT |
879 | ti->private = cc; |
880 | return 0; | |
881 | ||
9934a8be MB |
882 | bad_queue: |
883 | kfree(cc->iv_mode); | |
55b42c5a DM |
884 | bad_iv_mode: |
885 | dm_put_device(ti, cc->dev); | |
1da177e4 | 886 | bad5: |
6a24c718 MB |
887 | bioset_free(cc->bs); |
888 | bad_bs: | |
1da177e4 LT |
889 | mempool_destroy(cc->page_pool); |
890 | bad4: | |
891 | mempool_destroy(cc->io_pool); | |
892 | bad3: | |
893 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) | |
894 | cc->iv_gen_ops->dtr(cc); | |
895 | bad2: | |
d1806f6a | 896 | crypto_free_blkcipher(tfm); |
1da177e4 | 897 | bad1: |
9d3520a3 SR |
898 | /* Must zero key material before freeing */ |
899 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
900 | kfree(cc); |
901 | return -EINVAL; | |
902 | } | |
903 | ||
904 | static void crypt_dtr(struct dm_target *ti) | |
905 | { | |
906 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
907 | ||
9934a8be | 908 | destroy_workqueue(cc->queue); |
80b16c19 | 909 | |
6a24c718 | 910 | bioset_free(cc->bs); |
1da177e4 LT |
911 | mempool_destroy(cc->page_pool); |
912 | mempool_destroy(cc->io_pool); | |
913 | ||
990a8baf | 914 | kfree(cc->iv_mode); |
1da177e4 LT |
915 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
916 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 917 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 918 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
919 | |
920 | /* Must zero key material before freeing */ | |
921 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
922 | kfree(cc); |
923 | } | |
924 | ||
1da177e4 LT |
925 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
926 | union map_info *map_context) | |
927 | { | |
8b004457 | 928 | struct crypt_config *cc = ti->private; |
028867ac | 929 | struct dm_crypt_io *io; |
1da177e4 | 930 | |
e48d4bbf | 931 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 932 | io->target = ti; |
8b004457 | 933 | io->base_bio = bio; |
23541d2d | 934 | io->error = io->post_process = 0; |
93e605c2 | 935 | atomic_set(&io->pending, 0); |
23541d2d | 936 | kcryptd_queue_io(io); |
1da177e4 | 937 | |
d2a7ad29 | 938 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
939 | } |
940 | ||
941 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
942 | char *result, unsigned int maxlen) | |
943 | { | |
944 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
945 | unsigned int sz = 0; |
946 | ||
947 | switch (type) { | |
948 | case STATUSTYPE_INFO: | |
949 | result[0] = '\0'; | |
950 | break; | |
951 | ||
952 | case STATUSTYPE_TABLE: | |
1da177e4 | 953 | if (cc->iv_mode) |
37af6560 CS |
954 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
955 | cc->iv_mode); | |
1da177e4 | 956 | else |
37af6560 | 957 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
958 | |
959 | if (cc->key_size > 0) { | |
960 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
961 | return -ENOMEM; | |
962 | ||
963 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
964 | sz += cc->key_size << 1; | |
965 | } else { | |
966 | if (sz >= maxlen) | |
967 | return -ENOMEM; | |
968 | result[sz++] = '-'; | |
969 | } | |
970 | ||
4ee218cd AM |
971 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
972 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
973 | break; |
974 | } | |
975 | return 0; | |
976 | } | |
977 | ||
e48d4bbf MB |
978 | static void crypt_postsuspend(struct dm_target *ti) |
979 | { | |
980 | struct crypt_config *cc = ti->private; | |
981 | ||
982 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
983 | } | |
984 | ||
985 | static int crypt_preresume(struct dm_target *ti) | |
986 | { | |
987 | struct crypt_config *cc = ti->private; | |
988 | ||
989 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
990 | DMERR("aborting resume - crypt key is not set."); | |
991 | return -EAGAIN; | |
992 | } | |
993 | ||
994 | return 0; | |
995 | } | |
996 | ||
997 | static void crypt_resume(struct dm_target *ti) | |
998 | { | |
999 | struct crypt_config *cc = ti->private; | |
1000 | ||
1001 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1002 | } | |
1003 | ||
1004 | /* Message interface | |
1005 | * key set <key> | |
1006 | * key wipe | |
1007 | */ | |
1008 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1009 | { | |
1010 | struct crypt_config *cc = ti->private; | |
1011 | ||
1012 | if (argc < 2) | |
1013 | goto error; | |
1014 | ||
1015 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1016 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1017 | DMWARN("not suspended during key manipulation."); | |
1018 | return -EINVAL; | |
1019 | } | |
1020 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1021 | return crypt_set_key(cc, argv[2]); | |
1022 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1023 | return crypt_wipe_key(cc); | |
1024 | } | |
1025 | ||
1026 | error: | |
1027 | DMWARN("unrecognised message received."); | |
1028 | return -EINVAL; | |
1029 | } | |
1030 | ||
1da177e4 LT |
1031 | static struct target_type crypt_target = { |
1032 | .name = "crypt", | |
46b47730 | 1033 | .version= {1, 5, 0}, |
1da177e4 LT |
1034 | .module = THIS_MODULE, |
1035 | .ctr = crypt_ctr, | |
1036 | .dtr = crypt_dtr, | |
1037 | .map = crypt_map, | |
1038 | .status = crypt_status, | |
e48d4bbf MB |
1039 | .postsuspend = crypt_postsuspend, |
1040 | .preresume = crypt_preresume, | |
1041 | .resume = crypt_resume, | |
1042 | .message = crypt_message, | |
1da177e4 LT |
1043 | }; |
1044 | ||
1045 | static int __init dm_crypt_init(void) | |
1046 | { | |
1047 | int r; | |
1048 | ||
028867ac | 1049 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1050 | if (!_crypt_io_pool) |
1051 | return -ENOMEM; | |
1052 | ||
1da177e4 LT |
1053 | r = dm_register_target(&crypt_target); |
1054 | if (r < 0) { | |
72d94861 | 1055 | DMERR("register failed %d", r); |
9934a8be | 1056 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1057 | } |
1058 | ||
1da177e4 LT |
1059 | return r; |
1060 | } | |
1061 | ||
1062 | static void __exit dm_crypt_exit(void) | |
1063 | { | |
1064 | int r = dm_unregister_target(&crypt_target); | |
1065 | ||
1066 | if (r < 0) | |
72d94861 | 1067 | DMERR("unregister failed %d", r); |
1da177e4 | 1068 | |
1da177e4 LT |
1069 | kmem_cache_destroy(_crypt_io_pool); |
1070 | } | |
1071 | ||
1072 | module_init(dm_crypt_init); | |
1073 | module_exit(dm_crypt_exit); | |
1074 | ||
1075 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1076 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1077 | MODULE_LICENSE("GPL"); |