Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
4e4eef64 | 4 | * Copyright (C) 2006-2007 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 | 29 | |
1da177e4 LT |
30 | /* |
31 | * context holding the current state of a multi-part conversion | |
32 | */ | |
33 | struct convert_context { | |
34 | struct bio *bio_in; | |
35 | struct bio *bio_out; | |
36 | unsigned int offset_in; | |
37 | unsigned int offset_out; | |
38 | unsigned int idx_in; | |
39 | unsigned int idx_out; | |
40 | sector_t sector; | |
1da177e4 LT |
41 | }; |
42 | ||
53017030 MB |
43 | /* |
44 | * per bio private data | |
45 | */ | |
46 | struct dm_crypt_io { | |
47 | struct dm_target *target; | |
48 | struct bio *base_bio; | |
49 | struct work_struct work; | |
50 | ||
51 | struct convert_context ctx; | |
52 | ||
53 | atomic_t pending; | |
54 | int error; | |
0c395b0f | 55 | sector_t sector; |
53017030 MB |
56 | }; |
57 | ||
01482b76 MB |
58 | struct dm_crypt_request { |
59 | struct scatterlist sg_in; | |
60 | struct scatterlist sg_out; | |
61 | }; | |
62 | ||
1da177e4 LT |
63 | struct crypt_config; |
64 | ||
65 | struct crypt_iv_operations { | |
66 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 67 | const char *opts); |
1da177e4 LT |
68 | void (*dtr)(struct crypt_config *cc); |
69 | const char *(*status)(struct crypt_config *cc); | |
70 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
71 | }; | |
72 | ||
73 | /* | |
74 | * Crypt: maps a linear range of a block device | |
75 | * and encrypts / decrypts at the same time. | |
76 | */ | |
e48d4bbf | 77 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
78 | struct crypt_config { |
79 | struct dm_dev *dev; | |
80 | sector_t start; | |
81 | ||
82 | /* | |
ddd42edf MB |
83 | * pool for per bio private data, crypto requests and |
84 | * encryption requeusts/buffer pages | |
1da177e4 LT |
85 | */ |
86 | mempool_t *io_pool; | |
ddd42edf | 87 | mempool_t *req_pool; |
1da177e4 | 88 | mempool_t *page_pool; |
6a24c718 | 89 | struct bio_set *bs; |
1da177e4 | 90 | |
cabf08e4 MB |
91 | struct workqueue_struct *io_queue; |
92 | struct workqueue_struct *crypt_queue; | |
1da177e4 LT |
93 | /* |
94 | * crypto related data | |
95 | */ | |
96 | struct crypt_iv_operations *iv_gen_ops; | |
97 | char *iv_mode; | |
79066ad3 HX |
98 | union { |
99 | struct crypto_cipher *essiv_tfm; | |
100 | int benbi_shift; | |
101 | } iv_gen_private; | |
1da177e4 LT |
102 | sector_t iv_offset; |
103 | unsigned int iv_size; | |
104 | ||
ddd42edf MB |
105 | /* |
106 | * Layout of each crypto request: | |
107 | * | |
108 | * struct ablkcipher_request | |
109 | * context | |
110 | * padding | |
111 | * struct dm_crypt_request | |
112 | * padding | |
113 | * IV | |
114 | * | |
115 | * The padding is added so that dm_crypt_request and the IV are | |
116 | * correctly aligned. | |
117 | */ | |
118 | unsigned int dmreq_start; | |
119 | struct ablkcipher_request *req; | |
120 | ||
d1806f6a HX |
121 | char cipher[CRYPTO_MAX_ALG_NAME]; |
122 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
123 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 124 | unsigned long flags; |
1da177e4 LT |
125 | unsigned int key_size; |
126 | u8 key[0]; | |
127 | }; | |
128 | ||
6a24c718 | 129 | #define MIN_IOS 16 |
1da177e4 LT |
130 | #define MIN_POOL_PAGES 32 |
131 | #define MIN_BIO_PAGES 8 | |
132 | ||
e18b890b | 133 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 134 | |
028867ac | 135 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 136 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 137 | |
1da177e4 LT |
138 | /* |
139 | * Different IV generation algorithms: | |
140 | * | |
3c164bd8 | 141 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 142 | * number, padded with zeros if necessary. |
1da177e4 | 143 | * |
3c164bd8 RS |
144 | * essiv: "encrypted sector|salt initial vector", the sector number is |
145 | * encrypted with the bulk cipher using a salt as key. The salt | |
146 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 147 | * |
48527fa7 RS |
148 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
149 | * (needed for LRW-32-AES and possible other narrow block modes) | |
150 | * | |
46b47730 LN |
151 | * null: the initial vector is always zero. Provides compatibility with |
152 | * obsolete loop_fish2 devices. Do not use for new devices. | |
153 | * | |
1da177e4 LT |
154 | * plumb: unimplemented, see: |
155 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
156 | */ | |
157 | ||
158 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
159 | { | |
160 | memset(iv, 0, cc->iv_size); | |
161 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
162 | ||
163 | return 0; | |
164 | } | |
165 | ||
166 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 167 | const char *opts) |
1da177e4 | 168 | { |
d1806f6a | 169 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
170 | struct crypto_hash *hash_tfm; |
171 | struct hash_desc desc; | |
1da177e4 LT |
172 | struct scatterlist sg; |
173 | unsigned int saltsize; | |
174 | u8 *salt; | |
d1806f6a | 175 | int err; |
1da177e4 LT |
176 | |
177 | if (opts == NULL) { | |
72d94861 | 178 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
179 | return -EINVAL; |
180 | } | |
181 | ||
182 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
183 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
184 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 185 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 186 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
187 | } |
188 | ||
35058687 | 189 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
190 | salt = kmalloc(saltsize, GFP_KERNEL); |
191 | if (salt == NULL) { | |
72d94861 | 192 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 193 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
194 | return -ENOMEM; |
195 | } | |
196 | ||
68e3f5dd | 197 | sg_init_one(&sg, cc->key, cc->key_size); |
35058687 HX |
198 | desc.tfm = hash_tfm; |
199 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
200 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
201 | crypto_free_hash(hash_tfm); | |
202 | ||
203 | if (err) { | |
204 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 205 | kfree(salt); |
35058687 HX |
206 | return err; |
207 | } | |
1da177e4 LT |
208 | |
209 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
210 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
211 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 212 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 213 | kfree(salt); |
d1806f6a | 214 | return PTR_ERR(essiv_tfm); |
1da177e4 | 215 | } |
d1806f6a HX |
216 | if (crypto_cipher_blocksize(essiv_tfm) != |
217 | crypto_blkcipher_ivsize(cc->tfm)) { | |
72d94861 | 218 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 219 | "not match IV size of block cipher"; |
d1806f6a | 220 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
221 | kfree(salt); |
222 | return -EINVAL; | |
223 | } | |
d1806f6a HX |
224 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
225 | if (err) { | |
72d94861 | 226 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 227 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 228 | kfree(salt); |
d1806f6a | 229 | return err; |
1da177e4 LT |
230 | } |
231 | kfree(salt); | |
232 | ||
79066ad3 | 233 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
234 | return 0; |
235 | } | |
236 | ||
237 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
238 | { | |
79066ad3 HX |
239 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
240 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
241 | } |
242 | ||
243 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
244 | { | |
1da177e4 LT |
245 | memset(iv, 0, cc->iv_size); |
246 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 247 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
248 | return 0; |
249 | } | |
250 | ||
48527fa7 RS |
251 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
252 | const char *opts) | |
253 | { | |
254 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); | |
f0d1b0b3 | 255 | int log = ilog2(bs); |
48527fa7 RS |
256 | |
257 | /* we need to calculate how far we must shift the sector count | |
258 | * to get the cipher block count, we use this shift in _gen */ | |
259 | ||
260 | if (1 << log != bs) { | |
261 | ti->error = "cypher blocksize is not a power of 2"; | |
262 | return -EINVAL; | |
263 | } | |
264 | ||
265 | if (log > 9) { | |
266 | ti->error = "cypher blocksize is > 512"; | |
267 | return -EINVAL; | |
268 | } | |
269 | ||
79066ad3 | 270 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
271 | |
272 | return 0; | |
273 | } | |
274 | ||
275 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
276 | { | |
48527fa7 RS |
277 | } |
278 | ||
279 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
280 | { | |
79066ad3 HX |
281 | __be64 val; |
282 | ||
48527fa7 | 283 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
284 | |
285 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
286 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 287 | |
1da177e4 LT |
288 | return 0; |
289 | } | |
290 | ||
46b47730 LN |
291 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
292 | { | |
293 | memset(iv, 0, cc->iv_size); | |
294 | ||
295 | return 0; | |
296 | } | |
297 | ||
1da177e4 LT |
298 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
299 | .generator = crypt_iv_plain_gen | |
300 | }; | |
301 | ||
302 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
303 | .ctr = crypt_iv_essiv_ctr, | |
304 | .dtr = crypt_iv_essiv_dtr, | |
305 | .generator = crypt_iv_essiv_gen | |
306 | }; | |
307 | ||
48527fa7 RS |
308 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
309 | .ctr = crypt_iv_benbi_ctr, | |
310 | .dtr = crypt_iv_benbi_dtr, | |
311 | .generator = crypt_iv_benbi_gen | |
312 | }; | |
1da177e4 | 313 | |
46b47730 LN |
314 | static struct crypt_iv_operations crypt_iv_null_ops = { |
315 | .generator = crypt_iv_null_gen | |
316 | }; | |
317 | ||
858119e1 | 318 | static int |
1da177e4 LT |
319 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
320 | struct scatterlist *in, unsigned int length, | |
321 | int write, sector_t sector) | |
322 | { | |
45789328 | 323 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
d1806f6a HX |
324 | struct blkcipher_desc desc = { |
325 | .tfm = cc->tfm, | |
326 | .info = iv, | |
327 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, | |
328 | }; | |
1da177e4 LT |
329 | int r; |
330 | ||
331 | if (cc->iv_gen_ops) { | |
332 | r = cc->iv_gen_ops->generator(cc, iv, sector); | |
333 | if (r < 0) | |
334 | return r; | |
335 | ||
336 | if (write) | |
d1806f6a | 337 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
1da177e4 | 338 | else |
d1806f6a | 339 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
1da177e4 LT |
340 | } else { |
341 | if (write) | |
d1806f6a | 342 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
1da177e4 | 343 | else |
d1806f6a | 344 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
1da177e4 LT |
345 | } |
346 | ||
347 | return r; | |
348 | } | |
349 | ||
d469f841 MB |
350 | static void crypt_convert_init(struct crypt_config *cc, |
351 | struct convert_context *ctx, | |
352 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 353 | sector_t sector) |
1da177e4 LT |
354 | { |
355 | ctx->bio_in = bio_in; | |
356 | ctx->bio_out = bio_out; | |
357 | ctx->offset_in = 0; | |
358 | ctx->offset_out = 0; | |
359 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
360 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
361 | ctx->sector = sector + cc->iv_offset; | |
1da177e4 LT |
362 | } |
363 | ||
01482b76 MB |
364 | static int crypt_convert_block(struct crypt_config *cc, |
365 | struct convert_context *ctx) | |
366 | { | |
367 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
368 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
369 | struct dm_crypt_request dmreq; | |
370 | ||
371 | sg_init_table(&dmreq.sg_in, 1); | |
372 | sg_set_page(&dmreq.sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
373 | bv_in->bv_offset + ctx->offset_in); | |
374 | ||
375 | sg_init_table(&dmreq.sg_out, 1); | |
376 | sg_set_page(&dmreq.sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
377 | bv_out->bv_offset + ctx->offset_out); | |
378 | ||
379 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
380 | if (ctx->offset_in >= bv_in->bv_len) { | |
381 | ctx->offset_in = 0; | |
382 | ctx->idx_in++; | |
383 | } | |
384 | ||
385 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
386 | if (ctx->offset_out >= bv_out->bv_len) { | |
387 | ctx->offset_out = 0; | |
388 | ctx->idx_out++; | |
389 | } | |
390 | ||
391 | return crypt_convert_scatterlist(cc, &dmreq.sg_out, &dmreq.sg_in, | |
392 | dmreq.sg_in.length, | |
393 | bio_data_dir(ctx->bio_in) == WRITE, | |
394 | ctx->sector); | |
395 | } | |
396 | ||
ddd42edf MB |
397 | static void crypt_alloc_req(struct crypt_config *cc, |
398 | struct convert_context *ctx) | |
399 | { | |
400 | if (!cc->req) | |
401 | cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
402 | } | |
403 | ||
1da177e4 LT |
404 | /* |
405 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
406 | */ | |
407 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 408 | struct convert_context *ctx) |
1da177e4 LT |
409 | { |
410 | int r = 0; | |
411 | ||
412 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
413 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
01482b76 | 414 | r = crypt_convert_block(cc, ctx); |
1da177e4 LT |
415 | if (r < 0) |
416 | break; | |
417 | ||
418 | ctx->sector++; | |
419 | } | |
420 | ||
421 | return r; | |
422 | } | |
423 | ||
d469f841 MB |
424 | static void dm_crypt_bio_destructor(struct bio *bio) |
425 | { | |
028867ac | 426 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
427 | struct crypt_config *cc = io->target->private; |
428 | ||
429 | bio_free(bio, cc->bs); | |
d469f841 | 430 | } |
6a24c718 | 431 | |
1da177e4 LT |
432 | /* |
433 | * Generate a new unfragmented bio with the given size | |
434 | * This should never violate the device limitations | |
435 | * May return a smaller bio when running out of pages | |
436 | */ | |
028867ac | 437 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 438 | { |
027581f3 | 439 | struct crypt_config *cc = io->target->private; |
8b004457 | 440 | struct bio *clone; |
1da177e4 | 441 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 442 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
443 | unsigned i, len; |
444 | struct page *page; | |
1da177e4 | 445 | |
2f9941b6 | 446 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 447 | if (!clone) |
1da177e4 | 448 | return NULL; |
1da177e4 | 449 | |
027581f3 | 450 | clone_init(io, clone); |
6a24c718 | 451 | |
f97380bc | 452 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
453 | page = mempool_alloc(cc->page_pool, gfp_mask); |
454 | if (!page) | |
1da177e4 LT |
455 | break; |
456 | ||
457 | /* | |
458 | * if additional pages cannot be allocated without waiting, | |
459 | * return a partially allocated bio, the caller will then try | |
460 | * to allocate additional bios while submitting this partial bio | |
461 | */ | |
f97380bc | 462 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
463 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
464 | ||
91e10625 MB |
465 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
466 | ||
467 | if (!bio_add_page(clone, page, len, 0)) { | |
468 | mempool_free(page, cc->page_pool); | |
469 | break; | |
470 | } | |
1da177e4 | 471 | |
91e10625 | 472 | size -= len; |
1da177e4 LT |
473 | } |
474 | ||
8b004457 MB |
475 | if (!clone->bi_size) { |
476 | bio_put(clone); | |
1da177e4 LT |
477 | return NULL; |
478 | } | |
479 | ||
8b004457 | 480 | return clone; |
1da177e4 LT |
481 | } |
482 | ||
644bd2f0 | 483 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 484 | { |
644bd2f0 | 485 | unsigned int i; |
1da177e4 LT |
486 | struct bio_vec *bv; |
487 | ||
644bd2f0 | 488 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 489 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
490 | BUG_ON(!bv->bv_page); |
491 | mempool_free(bv->bv_page, cc->page_pool); | |
492 | bv->bv_page = NULL; | |
493 | } | |
494 | } | |
495 | ||
496 | /* | |
497 | * One of the bios was finished. Check for completion of | |
498 | * the whole request and correctly clean up the buffer. | |
499 | */ | |
5742fd77 | 500 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 501 | { |
5742fd77 | 502 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
503 | |
504 | if (!atomic_dec_and_test(&io->pending)) | |
505 | return; | |
506 | ||
6712ecf8 | 507 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
508 | mempool_free(io, cc->io_pool); |
509 | } | |
510 | ||
511 | /* | |
cabf08e4 | 512 | * kcryptd/kcryptd_io: |
1da177e4 LT |
513 | * |
514 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 515 | * interrupt context. |
cabf08e4 MB |
516 | * |
517 | * kcryptd performs the actual encryption or decryption. | |
518 | * | |
519 | * kcryptd_io performs the IO submission. | |
520 | * | |
521 | * They must be separated as otherwise the final stages could be | |
522 | * starved by new requests which can block in the first stages due | |
523 | * to memory allocation. | |
1da177e4 | 524 | */ |
6712ecf8 | 525 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 526 | { |
028867ac | 527 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 528 | struct crypt_config *cc = io->target->private; |
ee7a491e | 529 | unsigned rw = bio_data_dir(clone); |
8b004457 | 530 | |
adfe4770 MB |
531 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
532 | error = -EIO; | |
533 | ||
8b004457 | 534 | /* |
6712ecf8 | 535 | * free the processed pages |
8b004457 | 536 | */ |
ee7a491e | 537 | if (rw == WRITE) |
644bd2f0 | 538 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
539 | |
540 | bio_put(clone); | |
8b004457 | 541 | |
ee7a491e MB |
542 | if (rw == READ && !error) { |
543 | kcryptd_queue_crypt(io); | |
544 | return; | |
545 | } | |
5742fd77 MB |
546 | |
547 | if (unlikely(error)) | |
548 | io->error = error; | |
549 | ||
550 | crypt_dec_pending(io); | |
8b004457 MB |
551 | } |
552 | ||
028867ac | 553 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
554 | { |
555 | struct crypt_config *cc = io->target->private; | |
556 | ||
557 | clone->bi_private = io; | |
558 | clone->bi_end_io = crypt_endio; | |
559 | clone->bi_bdev = cc->dev->bdev; | |
560 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 561 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
562 | } |
563 | ||
4e4eef64 | 564 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
565 | { |
566 | struct crypt_config *cc = io->target->private; | |
567 | struct bio *base_bio = io->base_bio; | |
568 | struct bio *clone; | |
93e605c2 MB |
569 | |
570 | atomic_inc(&io->pending); | |
8b004457 MB |
571 | |
572 | /* | |
573 | * The block layer might modify the bvec array, so always | |
574 | * copy the required bvecs because we need the original | |
575 | * one in order to decrypt the whole bio data *afterwards*. | |
576 | */ | |
6a24c718 | 577 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 578 | if (unlikely(!clone)) { |
5742fd77 MB |
579 | io->error = -ENOMEM; |
580 | crypt_dec_pending(io); | |
23541d2d | 581 | return; |
93e605c2 | 582 | } |
8b004457 MB |
583 | |
584 | clone_init(io, clone); | |
585 | clone->bi_idx = 0; | |
586 | clone->bi_vcnt = bio_segments(base_bio); | |
587 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 588 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
589 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
590 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 591 | |
93e605c2 | 592 | generic_make_request(clone); |
8b004457 MB |
593 | } |
594 | ||
4e4eef64 MB |
595 | static void kcryptd_io_write(struct dm_crypt_io *io) |
596 | { | |
597 | } | |
598 | ||
395b167c AK |
599 | static void kcryptd_io(struct work_struct *work) |
600 | { | |
601 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
602 | ||
603 | if (bio_data_dir(io->base_bio) == READ) | |
604 | kcryptd_io_read(io); | |
605 | else | |
606 | kcryptd_io_write(io); | |
607 | } | |
608 | ||
609 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
610 | { | |
611 | struct crypt_config *cc = io->target->private; | |
612 | ||
613 | INIT_WORK(&io->work, kcryptd_io); | |
614 | queue_work(cc->io_queue, &io->work); | |
615 | } | |
616 | ||
4e4eef64 MB |
617 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error) |
618 | { | |
dec1cedf MB |
619 | struct bio *clone = io->ctx.bio_out; |
620 | struct crypt_config *cc = io->target->private; | |
621 | ||
622 | if (unlikely(error < 0)) { | |
623 | crypt_free_buffer_pages(cc, clone); | |
624 | bio_put(clone); | |
625 | io->error = -EIO; | |
dec1cedf MB |
626 | return; |
627 | } | |
628 | ||
629 | /* crypt_convert should have filled the clone bio */ | |
630 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
631 | ||
632 | clone->bi_sector = cc->start + io->sector; | |
633 | io->sector += bio_sectors(clone); | |
899c95d3 MB |
634 | |
635 | atomic_inc(&io->pending); | |
636 | generic_make_request(clone); | |
4e4eef64 MB |
637 | } |
638 | ||
84131db6 | 639 | static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io) |
8b004457 MB |
640 | { |
641 | struct crypt_config *cc = io->target->private; | |
8b004457 | 642 | struct bio *clone; |
dec1cedf MB |
643 | unsigned remaining = io->base_bio->bi_size; |
644 | int r; | |
8b004457 | 645 | |
93e605c2 MB |
646 | /* |
647 | * The allocated buffers can be smaller than the whole bio, | |
648 | * so repeat the whole process until all the data can be handled. | |
649 | */ | |
650 | while (remaining) { | |
f97380bc | 651 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 652 | if (unlikely(!clone)) { |
5742fd77 | 653 | io->error = -ENOMEM; |
23541d2d MB |
654 | return; |
655 | } | |
93e605c2 | 656 | |
53017030 MB |
657 | io->ctx.bio_out = clone; |
658 | io->ctx.idx_out = 0; | |
93e605c2 | 659 | |
dec1cedf | 660 | remaining -= clone->bi_size; |
93e605c2 | 661 | |
dec1cedf | 662 | r = crypt_convert(cc, &io->ctx); |
f97380bc | 663 | |
dec1cedf MB |
664 | kcryptd_crypt_write_io_submit(io, r); |
665 | if (unlikely(r < 0)) | |
666 | return; | |
93e605c2 | 667 | |
93e605c2 | 668 | /* out of memory -> run queues */ |
dec1cedf | 669 | if (unlikely(remaining)) |
98221eb7 | 670 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 671 | } |
8b004457 MB |
672 | } |
673 | ||
84131db6 MB |
674 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
675 | { | |
676 | struct crypt_config *cc = io->target->private; | |
677 | ||
899c95d3 MB |
678 | /* |
679 | * Prevent io from disappearing until this function completes. | |
680 | */ | |
84131db6 MB |
681 | atomic_inc(&io->pending); |
682 | ||
683 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector); | |
684 | kcryptd_crypt_write_convert_loop(io); | |
899c95d3 MB |
685 | |
686 | crypt_dec_pending(io); | |
84131db6 MB |
687 | } |
688 | ||
4e4eef64 | 689 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
690 | { |
691 | if (unlikely(error < 0)) | |
692 | io->error = -EIO; | |
693 | ||
694 | crypt_dec_pending(io); | |
695 | } | |
696 | ||
4e4eef64 | 697 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
698 | { |
699 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 700 | int r = 0; |
1da177e4 | 701 | |
53017030 | 702 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 703 | io->sector); |
1da177e4 | 704 | |
5742fd77 MB |
705 | r = crypt_convert(cc, &io->ctx); |
706 | ||
4e4eef64 | 707 | kcryptd_crypt_read_done(io, r); |
1da177e4 LT |
708 | } |
709 | ||
395b167c | 710 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 711 | { |
028867ac | 712 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 713 | |
cabf08e4 | 714 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 715 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 716 | else |
395b167c | 717 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
718 | } |
719 | ||
395b167c | 720 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 721 | { |
395b167c | 722 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 723 | |
395b167c AK |
724 | INIT_WORK(&io->work, kcryptd_crypt); |
725 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
726 | } |
727 | ||
728 | /* | |
729 | * Decode key from its hex representation | |
730 | */ | |
731 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
732 | { | |
733 | char buffer[3]; | |
734 | char *endp; | |
735 | unsigned int i; | |
736 | ||
737 | buffer[2] = '\0'; | |
738 | ||
8b004457 | 739 | for (i = 0; i < size; i++) { |
1da177e4 LT |
740 | buffer[0] = *hex++; |
741 | buffer[1] = *hex++; | |
742 | ||
743 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
744 | ||
745 | if (endp != &buffer[2]) | |
746 | return -EINVAL; | |
747 | } | |
748 | ||
749 | if (*hex != '\0') | |
750 | return -EINVAL; | |
751 | ||
752 | return 0; | |
753 | } | |
754 | ||
755 | /* | |
756 | * Encode key into its hex representation | |
757 | */ | |
758 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
759 | { | |
760 | unsigned int i; | |
761 | ||
8b004457 | 762 | for (i = 0; i < size; i++) { |
1da177e4 LT |
763 | sprintf(hex, "%02x", *key); |
764 | hex += 2; | |
765 | key++; | |
766 | } | |
767 | } | |
768 | ||
e48d4bbf MB |
769 | static int crypt_set_key(struct crypt_config *cc, char *key) |
770 | { | |
771 | unsigned key_size = strlen(key) >> 1; | |
772 | ||
773 | if (cc->key_size && cc->key_size != key_size) | |
774 | return -EINVAL; | |
775 | ||
776 | cc->key_size = key_size; /* initial settings */ | |
777 | ||
778 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 779 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
780 | return -EINVAL; |
781 | ||
782 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
783 | ||
784 | return 0; | |
785 | } | |
786 | ||
787 | static int crypt_wipe_key(struct crypt_config *cc) | |
788 | { | |
789 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
790 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
791 | return 0; | |
792 | } | |
793 | ||
1da177e4 LT |
794 | /* |
795 | * Construct an encryption mapping: | |
796 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
797 | */ | |
798 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
799 | { | |
800 | struct crypt_config *cc; | |
d1806f6a | 801 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
802 | char *tmp; |
803 | char *cipher; | |
804 | char *chainmode; | |
805 | char *ivmode; | |
806 | char *ivopts; | |
1da177e4 | 807 | unsigned int key_size; |
4ee218cd | 808 | unsigned long long tmpll; |
1da177e4 LT |
809 | |
810 | if (argc != 5) { | |
72d94861 | 811 | ti->error = "Not enough arguments"; |
1da177e4 LT |
812 | return -EINVAL; |
813 | } | |
814 | ||
815 | tmp = argv[0]; | |
816 | cipher = strsep(&tmp, "-"); | |
817 | chainmode = strsep(&tmp, "-"); | |
818 | ivopts = strsep(&tmp, "-"); | |
819 | ivmode = strsep(&ivopts, ":"); | |
820 | ||
821 | if (tmp) | |
72d94861 | 822 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
823 | |
824 | key_size = strlen(argv[1]) >> 1; | |
825 | ||
e48d4bbf | 826 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
827 | if (cc == NULL) { |
828 | ti->error = | |
72d94861 | 829 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
830 | return -ENOMEM; |
831 | } | |
832 | ||
e48d4bbf | 833 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 834 | ti->error = "Error decoding key"; |
636d5786 | 835 | goto bad_cipher; |
1da177e4 LT |
836 | } |
837 | ||
838 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
839 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
840 | chainmode = "cbc"; | |
841 | ivmode = "plain"; | |
842 | } | |
843 | ||
d1806f6a HX |
844 | if (strcmp(chainmode, "ecb") && !ivmode) { |
845 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 846 | goto bad_cipher; |
1da177e4 LT |
847 | } |
848 | ||
d469f841 MB |
849 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
850 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 851 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 852 | goto bad_cipher; |
1da177e4 LT |
853 | } |
854 | ||
d1806f6a HX |
855 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
856 | if (IS_ERR(tfm)) { | |
72d94861 | 857 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 858 | goto bad_cipher; |
1da177e4 | 859 | } |
1da177e4 | 860 | |
d1806f6a HX |
861 | strcpy(cc->cipher, cipher); |
862 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
863 | cc->tfm = tfm; |
864 | ||
865 | /* | |
48527fa7 | 866 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
867 | * See comments at iv code |
868 | */ | |
869 | ||
870 | if (ivmode == NULL) | |
871 | cc->iv_gen_ops = NULL; | |
872 | else if (strcmp(ivmode, "plain") == 0) | |
873 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
874 | else if (strcmp(ivmode, "essiv") == 0) | |
875 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
876 | else if (strcmp(ivmode, "benbi") == 0) |
877 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
878 | else if (strcmp(ivmode, "null") == 0) |
879 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 880 | else { |
72d94861 | 881 | ti->error = "Invalid IV mode"; |
636d5786 | 882 | goto bad_ivmode; |
1da177e4 LT |
883 | } |
884 | ||
885 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
886 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 887 | goto bad_ivmode; |
1da177e4 | 888 | |
d1806f6a HX |
889 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
890 | if (cc->iv_size) | |
1da177e4 | 891 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 892 | cc->iv_size = max(cc->iv_size, |
d469f841 | 893 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 894 | else { |
1da177e4 | 895 | if (cc->iv_gen_ops) { |
72d94861 | 896 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
897 | if (cc->iv_gen_ops->dtr) |
898 | cc->iv_gen_ops->dtr(cc); | |
899 | cc->iv_gen_ops = NULL; | |
900 | } | |
901 | } | |
902 | ||
93d2341c | 903 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 904 | if (!cc->io_pool) { |
72d94861 | 905 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 906 | goto bad_slab_pool; |
1da177e4 LT |
907 | } |
908 | ||
ddd42edf MB |
909 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
910 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); | |
911 | ||
912 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
913 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
914 | if (!cc->req_pool) { | |
915 | ti->error = "Cannot allocate crypt request mempool"; | |
916 | goto bad_req_pool; | |
917 | } | |
918 | cc->req = NULL; | |
919 | ||
a19b27ce | 920 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 921 | if (!cc->page_pool) { |
72d94861 | 922 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 923 | goto bad_page_pool; |
1da177e4 LT |
924 | } |
925 | ||
5972511b | 926 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
927 | if (!cc->bs) { |
928 | ti->error = "Cannot allocate crypt bioset"; | |
929 | goto bad_bs; | |
930 | } | |
931 | ||
d1806f6a | 932 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 933 | ti->error = "Error setting key"; |
636d5786 | 934 | goto bad_device; |
1da177e4 LT |
935 | } |
936 | ||
4ee218cd | 937 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 938 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 939 | goto bad_device; |
1da177e4 | 940 | } |
4ee218cd | 941 | cc->iv_offset = tmpll; |
1da177e4 | 942 | |
4ee218cd | 943 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 944 | ti->error = "Invalid device sector"; |
636d5786 | 945 | goto bad_device; |
1da177e4 | 946 | } |
4ee218cd | 947 | cc->start = tmpll; |
1da177e4 LT |
948 | |
949 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 950 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 951 | ti->error = "Device lookup failed"; |
636d5786 | 952 | goto bad_device; |
1da177e4 LT |
953 | } |
954 | ||
955 | if (ivmode && cc->iv_gen_ops) { | |
956 | if (ivopts) | |
957 | *(ivopts - 1) = ':'; | |
958 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
959 | if (!cc->iv_mode) { | |
72d94861 | 960 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 961 | goto bad_ivmode_string; |
1da177e4 LT |
962 | } |
963 | strcpy(cc->iv_mode, ivmode); | |
964 | } else | |
965 | cc->iv_mode = NULL; | |
966 | ||
cabf08e4 MB |
967 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
968 | if (!cc->io_queue) { | |
969 | ti->error = "Couldn't create kcryptd io queue"; | |
970 | goto bad_io_queue; | |
971 | } | |
972 | ||
973 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
974 | if (!cc->crypt_queue) { | |
9934a8be | 975 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 976 | goto bad_crypt_queue; |
9934a8be MB |
977 | } |
978 | ||
1da177e4 LT |
979 | ti->private = cc; |
980 | return 0; | |
981 | ||
cabf08e4 MB |
982 | bad_crypt_queue: |
983 | destroy_workqueue(cc->io_queue); | |
984 | bad_io_queue: | |
9934a8be | 985 | kfree(cc->iv_mode); |
636d5786 | 986 | bad_ivmode_string: |
55b42c5a | 987 | dm_put_device(ti, cc->dev); |
636d5786 | 988 | bad_device: |
6a24c718 MB |
989 | bioset_free(cc->bs); |
990 | bad_bs: | |
1da177e4 | 991 | mempool_destroy(cc->page_pool); |
636d5786 | 992 | bad_page_pool: |
ddd42edf MB |
993 | mempool_destroy(cc->req_pool); |
994 | bad_req_pool: | |
1da177e4 | 995 | mempool_destroy(cc->io_pool); |
636d5786 | 996 | bad_slab_pool: |
1da177e4 LT |
997 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
998 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 999 | bad_ivmode: |
d1806f6a | 1000 | crypto_free_blkcipher(tfm); |
636d5786 | 1001 | bad_cipher: |
9d3520a3 SR |
1002 | /* Must zero key material before freeing */ |
1003 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1004 | kfree(cc); |
1005 | return -EINVAL; | |
1006 | } | |
1007 | ||
1008 | static void crypt_dtr(struct dm_target *ti) | |
1009 | { | |
1010 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1011 | ||
cabf08e4 MB |
1012 | destroy_workqueue(cc->io_queue); |
1013 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1014 | |
ddd42edf MB |
1015 | if (cc->req) |
1016 | mempool_free(cc->req, cc->req_pool); | |
1017 | ||
6a24c718 | 1018 | bioset_free(cc->bs); |
1da177e4 | 1019 | mempool_destroy(cc->page_pool); |
ddd42edf | 1020 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1021 | mempool_destroy(cc->io_pool); |
1022 | ||
990a8baf | 1023 | kfree(cc->iv_mode); |
1da177e4 LT |
1024 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1025 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 1026 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 1027 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1028 | |
1029 | /* Must zero key material before freeing */ | |
1030 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1031 | kfree(cc); |
1032 | } | |
1033 | ||
1da177e4 LT |
1034 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1035 | union map_info *map_context) | |
1036 | { | |
8b004457 | 1037 | struct crypt_config *cc = ti->private; |
028867ac | 1038 | struct dm_crypt_io *io; |
1da177e4 | 1039 | |
e48d4bbf | 1040 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 1041 | io->target = ti; |
8b004457 | 1042 | io->base_bio = bio; |
0c395b0f | 1043 | io->sector = bio->bi_sector - ti->begin; |
cabf08e4 | 1044 | io->error = 0; |
93e605c2 | 1045 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
1046 | |
1047 | if (bio_data_dir(io->base_bio) == READ) | |
1048 | kcryptd_queue_io(io); | |
1049 | else | |
1050 | kcryptd_queue_crypt(io); | |
1da177e4 | 1051 | |
d2a7ad29 | 1052 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1053 | } |
1054 | ||
1055 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1056 | char *result, unsigned int maxlen) | |
1057 | { | |
1058 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1059 | unsigned int sz = 0; |
1060 | ||
1061 | switch (type) { | |
1062 | case STATUSTYPE_INFO: | |
1063 | result[0] = '\0'; | |
1064 | break; | |
1065 | ||
1066 | case STATUSTYPE_TABLE: | |
1da177e4 | 1067 | if (cc->iv_mode) |
37af6560 CS |
1068 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1069 | cc->iv_mode); | |
1da177e4 | 1070 | else |
37af6560 | 1071 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1072 | |
1073 | if (cc->key_size > 0) { | |
1074 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1075 | return -ENOMEM; | |
1076 | ||
1077 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1078 | sz += cc->key_size << 1; | |
1079 | } else { | |
1080 | if (sz >= maxlen) | |
1081 | return -ENOMEM; | |
1082 | result[sz++] = '-'; | |
1083 | } | |
1084 | ||
4ee218cd AM |
1085 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1086 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1087 | break; |
1088 | } | |
1089 | return 0; | |
1090 | } | |
1091 | ||
e48d4bbf MB |
1092 | static void crypt_postsuspend(struct dm_target *ti) |
1093 | { | |
1094 | struct crypt_config *cc = ti->private; | |
1095 | ||
1096 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1097 | } | |
1098 | ||
1099 | static int crypt_preresume(struct dm_target *ti) | |
1100 | { | |
1101 | struct crypt_config *cc = ti->private; | |
1102 | ||
1103 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1104 | DMERR("aborting resume - crypt key is not set."); | |
1105 | return -EAGAIN; | |
1106 | } | |
1107 | ||
1108 | return 0; | |
1109 | } | |
1110 | ||
1111 | static void crypt_resume(struct dm_target *ti) | |
1112 | { | |
1113 | struct crypt_config *cc = ti->private; | |
1114 | ||
1115 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1116 | } | |
1117 | ||
1118 | /* Message interface | |
1119 | * key set <key> | |
1120 | * key wipe | |
1121 | */ | |
1122 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1123 | { | |
1124 | struct crypt_config *cc = ti->private; | |
1125 | ||
1126 | if (argc < 2) | |
1127 | goto error; | |
1128 | ||
1129 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1130 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1131 | DMWARN("not suspended during key manipulation."); | |
1132 | return -EINVAL; | |
1133 | } | |
1134 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1135 | return crypt_set_key(cc, argv[2]); | |
1136 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1137 | return crypt_wipe_key(cc); | |
1138 | } | |
1139 | ||
1140 | error: | |
1141 | DMWARN("unrecognised message received."); | |
1142 | return -EINVAL; | |
1143 | } | |
1144 | ||
1da177e4 LT |
1145 | static struct target_type crypt_target = { |
1146 | .name = "crypt", | |
46b47730 | 1147 | .version= {1, 5, 0}, |
1da177e4 LT |
1148 | .module = THIS_MODULE, |
1149 | .ctr = crypt_ctr, | |
1150 | .dtr = crypt_dtr, | |
1151 | .map = crypt_map, | |
1152 | .status = crypt_status, | |
e48d4bbf MB |
1153 | .postsuspend = crypt_postsuspend, |
1154 | .preresume = crypt_preresume, | |
1155 | .resume = crypt_resume, | |
1156 | .message = crypt_message, | |
1da177e4 LT |
1157 | }; |
1158 | ||
1159 | static int __init dm_crypt_init(void) | |
1160 | { | |
1161 | int r; | |
1162 | ||
028867ac | 1163 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1164 | if (!_crypt_io_pool) |
1165 | return -ENOMEM; | |
1166 | ||
1da177e4 LT |
1167 | r = dm_register_target(&crypt_target); |
1168 | if (r < 0) { | |
72d94861 | 1169 | DMERR("register failed %d", r); |
9934a8be | 1170 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1171 | } |
1172 | ||
1da177e4 LT |
1173 | return r; |
1174 | } | |
1175 | ||
1176 | static void __exit dm_crypt_exit(void) | |
1177 | { | |
1178 | int r = dm_unregister_target(&crypt_target); | |
1179 | ||
1180 | if (r < 0) | |
72d94861 | 1181 | DMERR("unregister failed %d", r); |
1da177e4 | 1182 | |
1da177e4 LT |
1183 | kmem_cache_destroy(_crypt_io_pool); |
1184 | } | |
1185 | ||
1186 | module_init(dm_crypt_init); | |
1187 | module_exit(dm_crypt_exit); | |
1188 | ||
1189 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1190 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1191 | MODULE_LICENSE("GPL"); |