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 | ||
43d69034 | 9 | #include <linux/completion.h> |
d1806f6a | 10 | #include <linux/err.h> |
1da177e4 LT |
11 | #include <linux/module.h> |
12 | #include <linux/init.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/bio.h> | |
15 | #include <linux/blkdev.h> | |
16 | #include <linux/mempool.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/crypto.h> | |
19 | #include <linux/workqueue.h> | |
3fcfab16 | 20 | #include <linux/backing-dev.h> |
1da177e4 | 21 | #include <asm/atomic.h> |
378f058c | 22 | #include <linux/scatterlist.h> |
1da177e4 | 23 | #include <asm/page.h> |
48527fa7 | 24 | #include <asm/unaligned.h> |
1da177e4 LT |
25 | |
26 | #include "dm.h" | |
27 | ||
72d94861 | 28 | #define DM_MSG_PREFIX "crypt" |
e48d4bbf | 29 | #define MESG_STR(x) x, sizeof(x) |
1da177e4 | 30 | |
1da177e4 LT |
31 | /* |
32 | * context holding the current state of a multi-part conversion | |
33 | */ | |
34 | struct convert_context { | |
43d69034 | 35 | struct completion restart; |
1da177e4 LT |
36 | struct bio *bio_in; |
37 | struct bio *bio_out; | |
38 | unsigned int offset_in; | |
39 | unsigned int offset_out; | |
40 | unsigned int idx_in; | |
41 | unsigned int idx_out; | |
42 | sector_t sector; | |
43d69034 | 43 | atomic_t pending; |
1da177e4 LT |
44 | }; |
45 | ||
53017030 MB |
46 | /* |
47 | * per bio private data | |
48 | */ | |
49 | struct dm_crypt_io { | |
50 | struct dm_target *target; | |
51 | struct bio *base_bio; | |
52 | struct work_struct work; | |
53 | ||
54 | struct convert_context ctx; | |
55 | ||
56 | atomic_t pending; | |
57 | int error; | |
0c395b0f | 58 | sector_t sector; |
53017030 MB |
59 | }; |
60 | ||
01482b76 MB |
61 | struct dm_crypt_request { |
62 | struct scatterlist sg_in; | |
63 | struct scatterlist sg_out; | |
64 | }; | |
65 | ||
1da177e4 LT |
66 | struct crypt_config; |
67 | ||
68 | struct crypt_iv_operations { | |
69 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 70 | const char *opts); |
1da177e4 LT |
71 | void (*dtr)(struct crypt_config *cc); |
72 | const char *(*status)(struct crypt_config *cc); | |
73 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
74 | }; | |
75 | ||
76 | /* | |
77 | * Crypt: maps a linear range of a block device | |
78 | * and encrypts / decrypts at the same time. | |
79 | */ | |
e48d4bbf | 80 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
81 | struct crypt_config { |
82 | struct dm_dev *dev; | |
83 | sector_t start; | |
84 | ||
85 | /* | |
ddd42edf MB |
86 | * pool for per bio private data, crypto requests and |
87 | * encryption requeusts/buffer pages | |
1da177e4 LT |
88 | */ |
89 | mempool_t *io_pool; | |
ddd42edf | 90 | mempool_t *req_pool; |
1da177e4 | 91 | mempool_t *page_pool; |
6a24c718 | 92 | struct bio_set *bs; |
1da177e4 | 93 | |
cabf08e4 MB |
94 | struct workqueue_struct *io_queue; |
95 | struct workqueue_struct *crypt_queue; | |
1da177e4 LT |
96 | /* |
97 | * crypto related data | |
98 | */ | |
99 | struct crypt_iv_operations *iv_gen_ops; | |
100 | char *iv_mode; | |
79066ad3 HX |
101 | union { |
102 | struct crypto_cipher *essiv_tfm; | |
103 | int benbi_shift; | |
104 | } iv_gen_private; | |
1da177e4 LT |
105 | sector_t iv_offset; |
106 | unsigned int iv_size; | |
107 | ||
ddd42edf MB |
108 | /* |
109 | * Layout of each crypto request: | |
110 | * | |
111 | * struct ablkcipher_request | |
112 | * context | |
113 | * padding | |
114 | * struct dm_crypt_request | |
115 | * padding | |
116 | * IV | |
117 | * | |
118 | * The padding is added so that dm_crypt_request and the IV are | |
119 | * correctly aligned. | |
120 | */ | |
121 | unsigned int dmreq_start; | |
122 | struct ablkcipher_request *req; | |
123 | ||
d1806f6a HX |
124 | char cipher[CRYPTO_MAX_ALG_NAME]; |
125 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
126 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 127 | unsigned long flags; |
1da177e4 LT |
128 | unsigned int key_size; |
129 | u8 key[0]; | |
130 | }; | |
131 | ||
6a24c718 | 132 | #define MIN_IOS 16 |
1da177e4 LT |
133 | #define MIN_POOL_PAGES 32 |
134 | #define MIN_BIO_PAGES 8 | |
135 | ||
e18b890b | 136 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 137 | |
028867ac | 138 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 139 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 140 | |
1da177e4 LT |
141 | /* |
142 | * Different IV generation algorithms: | |
143 | * | |
3c164bd8 | 144 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 145 | * number, padded with zeros if necessary. |
1da177e4 | 146 | * |
3c164bd8 RS |
147 | * essiv: "encrypted sector|salt initial vector", the sector number is |
148 | * encrypted with the bulk cipher using a salt as key. The salt | |
149 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 150 | * |
48527fa7 RS |
151 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
152 | * (needed for LRW-32-AES and possible other narrow block modes) | |
153 | * | |
46b47730 LN |
154 | * null: the initial vector is always zero. Provides compatibility with |
155 | * obsolete loop_fish2 devices. Do not use for new devices. | |
156 | * | |
1da177e4 LT |
157 | * plumb: unimplemented, see: |
158 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
159 | */ | |
160 | ||
161 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
162 | { | |
163 | memset(iv, 0, cc->iv_size); | |
164 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
165 | ||
166 | return 0; | |
167 | } | |
168 | ||
169 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 170 | const char *opts) |
1da177e4 | 171 | { |
d1806f6a | 172 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
173 | struct crypto_hash *hash_tfm; |
174 | struct hash_desc desc; | |
1da177e4 LT |
175 | struct scatterlist sg; |
176 | unsigned int saltsize; | |
177 | u8 *salt; | |
d1806f6a | 178 | int err; |
1da177e4 LT |
179 | |
180 | if (opts == NULL) { | |
72d94861 | 181 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
182 | return -EINVAL; |
183 | } | |
184 | ||
185 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
186 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
187 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 188 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 189 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
190 | } |
191 | ||
35058687 | 192 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
193 | salt = kmalloc(saltsize, GFP_KERNEL); |
194 | if (salt == NULL) { | |
72d94861 | 195 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 196 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
197 | return -ENOMEM; |
198 | } | |
199 | ||
68e3f5dd | 200 | sg_init_one(&sg, cc->key, cc->key_size); |
35058687 HX |
201 | desc.tfm = hash_tfm; |
202 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
203 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
204 | crypto_free_hash(hash_tfm); | |
205 | ||
206 | if (err) { | |
207 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 208 | kfree(salt); |
35058687 HX |
209 | return err; |
210 | } | |
1da177e4 LT |
211 | |
212 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
213 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
214 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 215 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 216 | kfree(salt); |
d1806f6a | 217 | return PTR_ERR(essiv_tfm); |
1da177e4 | 218 | } |
d1806f6a HX |
219 | if (crypto_cipher_blocksize(essiv_tfm) != |
220 | crypto_blkcipher_ivsize(cc->tfm)) { | |
72d94861 | 221 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 222 | "not match IV size of block cipher"; |
d1806f6a | 223 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
224 | kfree(salt); |
225 | return -EINVAL; | |
226 | } | |
d1806f6a HX |
227 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
228 | if (err) { | |
72d94861 | 229 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 230 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 231 | kfree(salt); |
d1806f6a | 232 | return err; |
1da177e4 LT |
233 | } |
234 | kfree(salt); | |
235 | ||
79066ad3 | 236 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
237 | return 0; |
238 | } | |
239 | ||
240 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
241 | { | |
79066ad3 HX |
242 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
243 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
244 | } |
245 | ||
246 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
247 | { | |
1da177e4 LT |
248 | memset(iv, 0, cc->iv_size); |
249 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 250 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
251 | return 0; |
252 | } | |
253 | ||
48527fa7 RS |
254 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
255 | const char *opts) | |
256 | { | |
257 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); | |
f0d1b0b3 | 258 | int log = ilog2(bs); |
48527fa7 RS |
259 | |
260 | /* we need to calculate how far we must shift the sector count | |
261 | * to get the cipher block count, we use this shift in _gen */ | |
262 | ||
263 | if (1 << log != bs) { | |
264 | ti->error = "cypher blocksize is not a power of 2"; | |
265 | return -EINVAL; | |
266 | } | |
267 | ||
268 | if (log > 9) { | |
269 | ti->error = "cypher blocksize is > 512"; | |
270 | return -EINVAL; | |
271 | } | |
272 | ||
79066ad3 | 273 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
274 | |
275 | return 0; | |
276 | } | |
277 | ||
278 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
279 | { | |
48527fa7 RS |
280 | } |
281 | ||
282 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
283 | { | |
79066ad3 HX |
284 | __be64 val; |
285 | ||
48527fa7 | 286 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
287 | |
288 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
289 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 290 | |
1da177e4 LT |
291 | return 0; |
292 | } | |
293 | ||
46b47730 LN |
294 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
295 | { | |
296 | memset(iv, 0, cc->iv_size); | |
297 | ||
298 | return 0; | |
299 | } | |
300 | ||
1da177e4 LT |
301 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
302 | .generator = crypt_iv_plain_gen | |
303 | }; | |
304 | ||
305 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
306 | .ctr = crypt_iv_essiv_ctr, | |
307 | .dtr = crypt_iv_essiv_dtr, | |
308 | .generator = crypt_iv_essiv_gen | |
309 | }; | |
310 | ||
48527fa7 RS |
311 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
312 | .ctr = crypt_iv_benbi_ctr, | |
313 | .dtr = crypt_iv_benbi_dtr, | |
314 | .generator = crypt_iv_benbi_gen | |
315 | }; | |
1da177e4 | 316 | |
46b47730 LN |
317 | static struct crypt_iv_operations crypt_iv_null_ops = { |
318 | .generator = crypt_iv_null_gen | |
319 | }; | |
320 | ||
858119e1 | 321 | static int |
1da177e4 LT |
322 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
323 | struct scatterlist *in, unsigned int length, | |
324 | int write, sector_t sector) | |
325 | { | |
45789328 | 326 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
d1806f6a HX |
327 | struct blkcipher_desc desc = { |
328 | .tfm = cc->tfm, | |
329 | .info = iv, | |
330 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, | |
331 | }; | |
1da177e4 LT |
332 | int r; |
333 | ||
334 | if (cc->iv_gen_ops) { | |
335 | r = cc->iv_gen_ops->generator(cc, iv, sector); | |
336 | if (r < 0) | |
337 | return r; | |
338 | ||
339 | if (write) | |
d1806f6a | 340 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
1da177e4 | 341 | else |
d1806f6a | 342 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
1da177e4 LT |
343 | } else { |
344 | if (write) | |
d1806f6a | 345 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
1da177e4 | 346 | else |
d1806f6a | 347 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
1da177e4 LT |
348 | } |
349 | ||
350 | return r; | |
351 | } | |
352 | ||
d469f841 MB |
353 | static void crypt_convert_init(struct crypt_config *cc, |
354 | struct convert_context *ctx, | |
355 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 356 | sector_t sector) |
1da177e4 LT |
357 | { |
358 | ctx->bio_in = bio_in; | |
359 | ctx->bio_out = bio_out; | |
360 | ctx->offset_in = 0; | |
361 | ctx->offset_out = 0; | |
362 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
363 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
364 | ctx->sector = sector + cc->iv_offset; | |
43d69034 MB |
365 | init_completion(&ctx->restart); |
366 | /* | |
367 | * Crypto operation can be asynchronous, | |
368 | * ctx->pending is increased after request submission. | |
369 | * We need to ensure that we don't call the crypt finish | |
370 | * operation before pending got incremented | |
371 | * (dependent on crypt submission return code). | |
372 | */ | |
373 | atomic_set(&ctx->pending, 2); | |
1da177e4 LT |
374 | } |
375 | ||
01482b76 MB |
376 | static int crypt_convert_block(struct crypt_config *cc, |
377 | struct convert_context *ctx) | |
378 | { | |
379 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
380 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
381 | struct dm_crypt_request dmreq; | |
382 | ||
383 | sg_init_table(&dmreq.sg_in, 1); | |
384 | sg_set_page(&dmreq.sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
385 | bv_in->bv_offset + ctx->offset_in); | |
386 | ||
387 | sg_init_table(&dmreq.sg_out, 1); | |
388 | sg_set_page(&dmreq.sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
389 | bv_out->bv_offset + ctx->offset_out); | |
390 | ||
391 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
392 | if (ctx->offset_in >= bv_in->bv_len) { | |
393 | ctx->offset_in = 0; | |
394 | ctx->idx_in++; | |
395 | } | |
396 | ||
397 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
398 | if (ctx->offset_out >= bv_out->bv_len) { | |
399 | ctx->offset_out = 0; | |
400 | ctx->idx_out++; | |
401 | } | |
402 | ||
403 | return crypt_convert_scatterlist(cc, &dmreq.sg_out, &dmreq.sg_in, | |
404 | dmreq.sg_in.length, | |
405 | bio_data_dir(ctx->bio_in) == WRITE, | |
406 | ctx->sector); | |
407 | } | |
408 | ||
95497a96 MB |
409 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
410 | int error); | |
ddd42edf MB |
411 | static void crypt_alloc_req(struct crypt_config *cc, |
412 | struct convert_context *ctx) | |
413 | { | |
414 | if (!cc->req) | |
415 | cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
95497a96 MB |
416 | ablkcipher_request_set_tfm(cc->req, cc->tfm); |
417 | ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | | |
418 | CRYPTO_TFM_REQ_MAY_SLEEP, | |
419 | kcryptd_async_done, ctx); | |
ddd42edf MB |
420 | } |
421 | ||
1da177e4 LT |
422 | /* |
423 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
424 | */ | |
425 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 426 | struct convert_context *ctx) |
1da177e4 LT |
427 | { |
428 | int r = 0; | |
429 | ||
430 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
431 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
01482b76 | 432 | r = crypt_convert_block(cc, ctx); |
1da177e4 LT |
433 | if (r < 0) |
434 | break; | |
435 | ||
436 | ctx->sector++; | |
437 | } | |
438 | ||
43d69034 MB |
439 | /* |
440 | * If there are pending crypto operation run async | |
441 | * code. Otherwise process return code synchronously. | |
442 | * The step of 2 ensures that async finish doesn't | |
443 | * call crypto finish too early. | |
444 | */ | |
445 | if (atomic_sub_return(2, &ctx->pending)) | |
446 | return -EINPROGRESS; | |
447 | ||
1da177e4 LT |
448 | return r; |
449 | } | |
450 | ||
d469f841 MB |
451 | static void dm_crypt_bio_destructor(struct bio *bio) |
452 | { | |
028867ac | 453 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
454 | struct crypt_config *cc = io->target->private; |
455 | ||
456 | bio_free(bio, cc->bs); | |
d469f841 | 457 | } |
6a24c718 | 458 | |
1da177e4 LT |
459 | /* |
460 | * Generate a new unfragmented bio with the given size | |
461 | * This should never violate the device limitations | |
462 | * May return a smaller bio when running out of pages | |
463 | */ | |
028867ac | 464 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 465 | { |
027581f3 | 466 | struct crypt_config *cc = io->target->private; |
8b004457 | 467 | struct bio *clone; |
1da177e4 | 468 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 469 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
470 | unsigned i, len; |
471 | struct page *page; | |
1da177e4 | 472 | |
2f9941b6 | 473 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 474 | if (!clone) |
1da177e4 | 475 | return NULL; |
1da177e4 | 476 | |
027581f3 | 477 | clone_init(io, clone); |
6a24c718 | 478 | |
f97380bc | 479 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
480 | page = mempool_alloc(cc->page_pool, gfp_mask); |
481 | if (!page) | |
1da177e4 LT |
482 | break; |
483 | ||
484 | /* | |
485 | * if additional pages cannot be allocated without waiting, | |
486 | * return a partially allocated bio, the caller will then try | |
487 | * to allocate additional bios while submitting this partial bio | |
488 | */ | |
f97380bc | 489 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
490 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
491 | ||
91e10625 MB |
492 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
493 | ||
494 | if (!bio_add_page(clone, page, len, 0)) { | |
495 | mempool_free(page, cc->page_pool); | |
496 | break; | |
497 | } | |
1da177e4 | 498 | |
91e10625 | 499 | size -= len; |
1da177e4 LT |
500 | } |
501 | ||
8b004457 MB |
502 | if (!clone->bi_size) { |
503 | bio_put(clone); | |
1da177e4 LT |
504 | return NULL; |
505 | } | |
506 | ||
8b004457 | 507 | return clone; |
1da177e4 LT |
508 | } |
509 | ||
644bd2f0 | 510 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 511 | { |
644bd2f0 | 512 | unsigned int i; |
1da177e4 LT |
513 | struct bio_vec *bv; |
514 | ||
644bd2f0 | 515 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 516 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
517 | BUG_ON(!bv->bv_page); |
518 | mempool_free(bv->bv_page, cc->page_pool); | |
519 | bv->bv_page = NULL; | |
520 | } | |
521 | } | |
522 | ||
523 | /* | |
524 | * One of the bios was finished. Check for completion of | |
525 | * the whole request and correctly clean up the buffer. | |
526 | */ | |
5742fd77 | 527 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 528 | { |
5742fd77 | 529 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
530 | |
531 | if (!atomic_dec_and_test(&io->pending)) | |
532 | return; | |
533 | ||
6712ecf8 | 534 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
535 | mempool_free(io, cc->io_pool); |
536 | } | |
537 | ||
538 | /* | |
cabf08e4 | 539 | * kcryptd/kcryptd_io: |
1da177e4 LT |
540 | * |
541 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 542 | * interrupt context. |
cabf08e4 MB |
543 | * |
544 | * kcryptd performs the actual encryption or decryption. | |
545 | * | |
546 | * kcryptd_io performs the IO submission. | |
547 | * | |
548 | * They must be separated as otherwise the final stages could be | |
549 | * starved by new requests which can block in the first stages due | |
550 | * to memory allocation. | |
1da177e4 | 551 | */ |
6712ecf8 | 552 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 553 | { |
028867ac | 554 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 555 | struct crypt_config *cc = io->target->private; |
ee7a491e | 556 | unsigned rw = bio_data_dir(clone); |
8b004457 | 557 | |
adfe4770 MB |
558 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
559 | error = -EIO; | |
560 | ||
8b004457 | 561 | /* |
6712ecf8 | 562 | * free the processed pages |
8b004457 | 563 | */ |
ee7a491e | 564 | if (rw == WRITE) |
644bd2f0 | 565 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
566 | |
567 | bio_put(clone); | |
8b004457 | 568 | |
ee7a491e MB |
569 | if (rw == READ && !error) { |
570 | kcryptd_queue_crypt(io); | |
571 | return; | |
572 | } | |
5742fd77 MB |
573 | |
574 | if (unlikely(error)) | |
575 | io->error = error; | |
576 | ||
577 | crypt_dec_pending(io); | |
8b004457 MB |
578 | } |
579 | ||
028867ac | 580 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
581 | { |
582 | struct crypt_config *cc = io->target->private; | |
583 | ||
584 | clone->bi_private = io; | |
585 | clone->bi_end_io = crypt_endio; | |
586 | clone->bi_bdev = cc->dev->bdev; | |
587 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 588 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
589 | } |
590 | ||
4e4eef64 | 591 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
592 | { |
593 | struct crypt_config *cc = io->target->private; | |
594 | struct bio *base_bio = io->base_bio; | |
595 | struct bio *clone; | |
93e605c2 MB |
596 | |
597 | atomic_inc(&io->pending); | |
8b004457 MB |
598 | |
599 | /* | |
600 | * The block layer might modify the bvec array, so always | |
601 | * copy the required bvecs because we need the original | |
602 | * one in order to decrypt the whole bio data *afterwards*. | |
603 | */ | |
6a24c718 | 604 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 605 | if (unlikely(!clone)) { |
5742fd77 MB |
606 | io->error = -ENOMEM; |
607 | crypt_dec_pending(io); | |
23541d2d | 608 | return; |
93e605c2 | 609 | } |
8b004457 MB |
610 | |
611 | clone_init(io, clone); | |
612 | clone->bi_idx = 0; | |
613 | clone->bi_vcnt = bio_segments(base_bio); | |
614 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 615 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
616 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
617 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 618 | |
93e605c2 | 619 | generic_make_request(clone); |
8b004457 MB |
620 | } |
621 | ||
4e4eef64 MB |
622 | static void kcryptd_io_write(struct dm_crypt_io *io) |
623 | { | |
95497a96 MB |
624 | struct bio *clone = io->ctx.bio_out; |
625 | ||
626 | generic_make_request(clone); | |
4e4eef64 MB |
627 | } |
628 | ||
395b167c AK |
629 | static void kcryptd_io(struct work_struct *work) |
630 | { | |
631 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
632 | ||
633 | if (bio_data_dir(io->base_bio) == READ) | |
634 | kcryptd_io_read(io); | |
635 | else | |
636 | kcryptd_io_write(io); | |
637 | } | |
638 | ||
639 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
640 | { | |
641 | struct crypt_config *cc = io->target->private; | |
642 | ||
643 | INIT_WORK(&io->work, kcryptd_io); | |
644 | queue_work(cc->io_queue, &io->work); | |
645 | } | |
646 | ||
95497a96 MB |
647 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
648 | int error, int async) | |
4e4eef64 | 649 | { |
dec1cedf MB |
650 | struct bio *clone = io->ctx.bio_out; |
651 | struct crypt_config *cc = io->target->private; | |
652 | ||
653 | if (unlikely(error < 0)) { | |
654 | crypt_free_buffer_pages(cc, clone); | |
655 | bio_put(clone); | |
656 | io->error = -EIO; | |
dec1cedf MB |
657 | return; |
658 | } | |
659 | ||
660 | /* crypt_convert should have filled the clone bio */ | |
661 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
662 | ||
663 | clone->bi_sector = cc->start + io->sector; | |
664 | io->sector += bio_sectors(clone); | |
899c95d3 | 665 | |
95497a96 MB |
666 | if (async) |
667 | kcryptd_queue_io(io); | |
668 | else { | |
669 | atomic_inc(&io->pending); | |
670 | generic_make_request(clone); | |
671 | } | |
4e4eef64 MB |
672 | } |
673 | ||
84131db6 | 674 | static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io) |
8b004457 MB |
675 | { |
676 | struct crypt_config *cc = io->target->private; | |
8b004457 | 677 | struct bio *clone; |
dec1cedf MB |
678 | unsigned remaining = io->base_bio->bi_size; |
679 | int r; | |
8b004457 | 680 | |
93e605c2 MB |
681 | /* |
682 | * The allocated buffers can be smaller than the whole bio, | |
683 | * so repeat the whole process until all the data can be handled. | |
684 | */ | |
685 | while (remaining) { | |
f97380bc | 686 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 687 | if (unlikely(!clone)) { |
5742fd77 | 688 | io->error = -ENOMEM; |
23541d2d MB |
689 | return; |
690 | } | |
93e605c2 | 691 | |
53017030 MB |
692 | io->ctx.bio_out = clone; |
693 | io->ctx.idx_out = 0; | |
93e605c2 | 694 | |
dec1cedf | 695 | remaining -= clone->bi_size; |
93e605c2 | 696 | |
dec1cedf | 697 | r = crypt_convert(cc, &io->ctx); |
f97380bc | 698 | |
95497a96 | 699 | kcryptd_crypt_write_io_submit(io, r, 0); |
dec1cedf MB |
700 | if (unlikely(r < 0)) |
701 | return; | |
93e605c2 | 702 | |
93e605c2 | 703 | /* out of memory -> run queues */ |
dec1cedf | 704 | if (unlikely(remaining)) |
98221eb7 | 705 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 706 | } |
8b004457 MB |
707 | } |
708 | ||
84131db6 MB |
709 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
710 | { | |
711 | struct crypt_config *cc = io->target->private; | |
712 | ||
899c95d3 MB |
713 | /* |
714 | * Prevent io from disappearing until this function completes. | |
715 | */ | |
84131db6 MB |
716 | atomic_inc(&io->pending); |
717 | ||
718 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector); | |
719 | kcryptd_crypt_write_convert_loop(io); | |
899c95d3 MB |
720 | |
721 | crypt_dec_pending(io); | |
84131db6 MB |
722 | } |
723 | ||
4e4eef64 | 724 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
725 | { |
726 | if (unlikely(error < 0)) | |
727 | io->error = -EIO; | |
728 | ||
729 | crypt_dec_pending(io); | |
730 | } | |
731 | ||
4e4eef64 | 732 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
733 | { |
734 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 735 | int r = 0; |
1da177e4 | 736 | |
53017030 | 737 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 738 | io->sector); |
1da177e4 | 739 | |
5742fd77 MB |
740 | r = crypt_convert(cc, &io->ctx); |
741 | ||
4e4eef64 | 742 | kcryptd_crypt_read_done(io, r); |
1da177e4 LT |
743 | } |
744 | ||
95497a96 MB |
745 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
746 | int error) | |
747 | { | |
748 | struct convert_context *ctx = async_req->data; | |
749 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); | |
750 | struct crypt_config *cc = io->target->private; | |
751 | ||
752 | if (error == -EINPROGRESS) { | |
753 | complete(&ctx->restart); | |
754 | return; | |
755 | } | |
756 | ||
757 | mempool_free(ablkcipher_request_cast(async_req), cc->req_pool); | |
758 | ||
759 | if (!atomic_dec_and_test(&ctx->pending)) | |
760 | return; | |
761 | ||
762 | if (bio_data_dir(io->base_bio) == READ) | |
763 | kcryptd_crypt_read_done(io, error); | |
764 | else | |
765 | kcryptd_crypt_write_io_submit(io, error, 1); | |
766 | } | |
767 | ||
395b167c | 768 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 769 | { |
028867ac | 770 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 771 | |
cabf08e4 | 772 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 773 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 774 | else |
395b167c | 775 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
776 | } |
777 | ||
395b167c | 778 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 779 | { |
395b167c | 780 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 781 | |
395b167c AK |
782 | INIT_WORK(&io->work, kcryptd_crypt); |
783 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
784 | } |
785 | ||
786 | /* | |
787 | * Decode key from its hex representation | |
788 | */ | |
789 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
790 | { | |
791 | char buffer[3]; | |
792 | char *endp; | |
793 | unsigned int i; | |
794 | ||
795 | buffer[2] = '\0'; | |
796 | ||
8b004457 | 797 | for (i = 0; i < size; i++) { |
1da177e4 LT |
798 | buffer[0] = *hex++; |
799 | buffer[1] = *hex++; | |
800 | ||
801 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
802 | ||
803 | if (endp != &buffer[2]) | |
804 | return -EINVAL; | |
805 | } | |
806 | ||
807 | if (*hex != '\0') | |
808 | return -EINVAL; | |
809 | ||
810 | return 0; | |
811 | } | |
812 | ||
813 | /* | |
814 | * Encode key into its hex representation | |
815 | */ | |
816 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
817 | { | |
818 | unsigned int i; | |
819 | ||
8b004457 | 820 | for (i = 0; i < size; i++) { |
1da177e4 LT |
821 | sprintf(hex, "%02x", *key); |
822 | hex += 2; | |
823 | key++; | |
824 | } | |
825 | } | |
826 | ||
e48d4bbf MB |
827 | static int crypt_set_key(struct crypt_config *cc, char *key) |
828 | { | |
829 | unsigned key_size = strlen(key) >> 1; | |
830 | ||
831 | if (cc->key_size && cc->key_size != key_size) | |
832 | return -EINVAL; | |
833 | ||
834 | cc->key_size = key_size; /* initial settings */ | |
835 | ||
836 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 837 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
838 | return -EINVAL; |
839 | ||
840 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
841 | ||
842 | return 0; | |
843 | } | |
844 | ||
845 | static int crypt_wipe_key(struct crypt_config *cc) | |
846 | { | |
847 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
848 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
849 | return 0; | |
850 | } | |
851 | ||
1da177e4 LT |
852 | /* |
853 | * Construct an encryption mapping: | |
854 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
855 | */ | |
856 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
857 | { | |
858 | struct crypt_config *cc; | |
d1806f6a | 859 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
860 | char *tmp; |
861 | char *cipher; | |
862 | char *chainmode; | |
863 | char *ivmode; | |
864 | char *ivopts; | |
1da177e4 | 865 | unsigned int key_size; |
4ee218cd | 866 | unsigned long long tmpll; |
1da177e4 LT |
867 | |
868 | if (argc != 5) { | |
72d94861 | 869 | ti->error = "Not enough arguments"; |
1da177e4 LT |
870 | return -EINVAL; |
871 | } | |
872 | ||
873 | tmp = argv[0]; | |
874 | cipher = strsep(&tmp, "-"); | |
875 | chainmode = strsep(&tmp, "-"); | |
876 | ivopts = strsep(&tmp, "-"); | |
877 | ivmode = strsep(&ivopts, ":"); | |
878 | ||
879 | if (tmp) | |
72d94861 | 880 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
881 | |
882 | key_size = strlen(argv[1]) >> 1; | |
883 | ||
e48d4bbf | 884 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
885 | if (cc == NULL) { |
886 | ti->error = | |
72d94861 | 887 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
888 | return -ENOMEM; |
889 | } | |
890 | ||
e48d4bbf | 891 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 892 | ti->error = "Error decoding key"; |
636d5786 | 893 | goto bad_cipher; |
1da177e4 LT |
894 | } |
895 | ||
896 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
897 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
898 | chainmode = "cbc"; | |
899 | ivmode = "plain"; | |
900 | } | |
901 | ||
d1806f6a HX |
902 | if (strcmp(chainmode, "ecb") && !ivmode) { |
903 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 904 | goto bad_cipher; |
1da177e4 LT |
905 | } |
906 | ||
d469f841 MB |
907 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
908 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 909 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 910 | goto bad_cipher; |
1da177e4 LT |
911 | } |
912 | ||
d1806f6a HX |
913 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
914 | if (IS_ERR(tfm)) { | |
72d94861 | 915 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 916 | goto bad_cipher; |
1da177e4 | 917 | } |
1da177e4 | 918 | |
d1806f6a HX |
919 | strcpy(cc->cipher, cipher); |
920 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
921 | cc->tfm = tfm; |
922 | ||
923 | /* | |
48527fa7 | 924 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
925 | * See comments at iv code |
926 | */ | |
927 | ||
928 | if (ivmode == NULL) | |
929 | cc->iv_gen_ops = NULL; | |
930 | else if (strcmp(ivmode, "plain") == 0) | |
931 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
932 | else if (strcmp(ivmode, "essiv") == 0) | |
933 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
934 | else if (strcmp(ivmode, "benbi") == 0) |
935 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
936 | else if (strcmp(ivmode, "null") == 0) |
937 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 938 | else { |
72d94861 | 939 | ti->error = "Invalid IV mode"; |
636d5786 | 940 | goto bad_ivmode; |
1da177e4 LT |
941 | } |
942 | ||
943 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
944 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 945 | goto bad_ivmode; |
1da177e4 | 946 | |
d1806f6a HX |
947 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
948 | if (cc->iv_size) | |
1da177e4 | 949 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 950 | cc->iv_size = max(cc->iv_size, |
d469f841 | 951 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 952 | else { |
1da177e4 | 953 | if (cc->iv_gen_ops) { |
72d94861 | 954 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
955 | if (cc->iv_gen_ops->dtr) |
956 | cc->iv_gen_ops->dtr(cc); | |
957 | cc->iv_gen_ops = NULL; | |
958 | } | |
959 | } | |
960 | ||
93d2341c | 961 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 962 | if (!cc->io_pool) { |
72d94861 | 963 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 964 | goto bad_slab_pool; |
1da177e4 LT |
965 | } |
966 | ||
ddd42edf MB |
967 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
968 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); | |
969 | ||
970 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
971 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
972 | if (!cc->req_pool) { | |
973 | ti->error = "Cannot allocate crypt request mempool"; | |
974 | goto bad_req_pool; | |
975 | } | |
976 | cc->req = NULL; | |
977 | ||
a19b27ce | 978 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 979 | if (!cc->page_pool) { |
72d94861 | 980 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 981 | goto bad_page_pool; |
1da177e4 LT |
982 | } |
983 | ||
5972511b | 984 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
985 | if (!cc->bs) { |
986 | ti->error = "Cannot allocate crypt bioset"; | |
987 | goto bad_bs; | |
988 | } | |
989 | ||
d1806f6a | 990 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 991 | ti->error = "Error setting key"; |
636d5786 | 992 | goto bad_device; |
1da177e4 LT |
993 | } |
994 | ||
4ee218cd | 995 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 996 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 997 | goto bad_device; |
1da177e4 | 998 | } |
4ee218cd | 999 | cc->iv_offset = tmpll; |
1da177e4 | 1000 | |
4ee218cd | 1001 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1002 | ti->error = "Invalid device sector"; |
636d5786 | 1003 | goto bad_device; |
1da177e4 | 1004 | } |
4ee218cd | 1005 | cc->start = tmpll; |
1da177e4 LT |
1006 | |
1007 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 1008 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 1009 | ti->error = "Device lookup failed"; |
636d5786 | 1010 | goto bad_device; |
1da177e4 LT |
1011 | } |
1012 | ||
1013 | if (ivmode && cc->iv_gen_ops) { | |
1014 | if (ivopts) | |
1015 | *(ivopts - 1) = ':'; | |
1016 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
1017 | if (!cc->iv_mode) { | |
72d94861 | 1018 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 1019 | goto bad_ivmode_string; |
1da177e4 LT |
1020 | } |
1021 | strcpy(cc->iv_mode, ivmode); | |
1022 | } else | |
1023 | cc->iv_mode = NULL; | |
1024 | ||
cabf08e4 MB |
1025 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
1026 | if (!cc->io_queue) { | |
1027 | ti->error = "Couldn't create kcryptd io queue"; | |
1028 | goto bad_io_queue; | |
1029 | } | |
1030 | ||
1031 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
1032 | if (!cc->crypt_queue) { | |
9934a8be | 1033 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 1034 | goto bad_crypt_queue; |
9934a8be MB |
1035 | } |
1036 | ||
1da177e4 LT |
1037 | ti->private = cc; |
1038 | return 0; | |
1039 | ||
cabf08e4 MB |
1040 | bad_crypt_queue: |
1041 | destroy_workqueue(cc->io_queue); | |
1042 | bad_io_queue: | |
9934a8be | 1043 | kfree(cc->iv_mode); |
636d5786 | 1044 | bad_ivmode_string: |
55b42c5a | 1045 | dm_put_device(ti, cc->dev); |
636d5786 | 1046 | bad_device: |
6a24c718 MB |
1047 | bioset_free(cc->bs); |
1048 | bad_bs: | |
1da177e4 | 1049 | mempool_destroy(cc->page_pool); |
636d5786 | 1050 | bad_page_pool: |
ddd42edf MB |
1051 | mempool_destroy(cc->req_pool); |
1052 | bad_req_pool: | |
1da177e4 | 1053 | mempool_destroy(cc->io_pool); |
636d5786 | 1054 | bad_slab_pool: |
1da177e4 LT |
1055 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1056 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 1057 | bad_ivmode: |
d1806f6a | 1058 | crypto_free_blkcipher(tfm); |
636d5786 | 1059 | bad_cipher: |
9d3520a3 SR |
1060 | /* Must zero key material before freeing */ |
1061 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1062 | kfree(cc); |
1063 | return -EINVAL; | |
1064 | } | |
1065 | ||
1066 | static void crypt_dtr(struct dm_target *ti) | |
1067 | { | |
1068 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1069 | ||
cabf08e4 MB |
1070 | destroy_workqueue(cc->io_queue); |
1071 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1072 | |
ddd42edf MB |
1073 | if (cc->req) |
1074 | mempool_free(cc->req, cc->req_pool); | |
1075 | ||
6a24c718 | 1076 | bioset_free(cc->bs); |
1da177e4 | 1077 | mempool_destroy(cc->page_pool); |
ddd42edf | 1078 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1079 | mempool_destroy(cc->io_pool); |
1080 | ||
990a8baf | 1081 | kfree(cc->iv_mode); |
1da177e4 LT |
1082 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1083 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 1084 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 1085 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1086 | |
1087 | /* Must zero key material before freeing */ | |
1088 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1089 | kfree(cc); |
1090 | } | |
1091 | ||
1da177e4 LT |
1092 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1093 | union map_info *map_context) | |
1094 | { | |
8b004457 | 1095 | struct crypt_config *cc = ti->private; |
028867ac | 1096 | struct dm_crypt_io *io; |
1da177e4 | 1097 | |
e48d4bbf | 1098 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 1099 | io->target = ti; |
8b004457 | 1100 | io->base_bio = bio; |
0c395b0f | 1101 | io->sector = bio->bi_sector - ti->begin; |
cabf08e4 | 1102 | io->error = 0; |
93e605c2 | 1103 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
1104 | |
1105 | if (bio_data_dir(io->base_bio) == READ) | |
1106 | kcryptd_queue_io(io); | |
1107 | else | |
1108 | kcryptd_queue_crypt(io); | |
1da177e4 | 1109 | |
d2a7ad29 | 1110 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1111 | } |
1112 | ||
1113 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1114 | char *result, unsigned int maxlen) | |
1115 | { | |
1116 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1117 | unsigned int sz = 0; |
1118 | ||
1119 | switch (type) { | |
1120 | case STATUSTYPE_INFO: | |
1121 | result[0] = '\0'; | |
1122 | break; | |
1123 | ||
1124 | case STATUSTYPE_TABLE: | |
1da177e4 | 1125 | if (cc->iv_mode) |
37af6560 CS |
1126 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1127 | cc->iv_mode); | |
1da177e4 | 1128 | else |
37af6560 | 1129 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1130 | |
1131 | if (cc->key_size > 0) { | |
1132 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1133 | return -ENOMEM; | |
1134 | ||
1135 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1136 | sz += cc->key_size << 1; | |
1137 | } else { | |
1138 | if (sz >= maxlen) | |
1139 | return -ENOMEM; | |
1140 | result[sz++] = '-'; | |
1141 | } | |
1142 | ||
4ee218cd AM |
1143 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1144 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1145 | break; |
1146 | } | |
1147 | return 0; | |
1148 | } | |
1149 | ||
e48d4bbf MB |
1150 | static void crypt_postsuspend(struct dm_target *ti) |
1151 | { | |
1152 | struct crypt_config *cc = ti->private; | |
1153 | ||
1154 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1155 | } | |
1156 | ||
1157 | static int crypt_preresume(struct dm_target *ti) | |
1158 | { | |
1159 | struct crypt_config *cc = ti->private; | |
1160 | ||
1161 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1162 | DMERR("aborting resume - crypt key is not set."); | |
1163 | return -EAGAIN; | |
1164 | } | |
1165 | ||
1166 | return 0; | |
1167 | } | |
1168 | ||
1169 | static void crypt_resume(struct dm_target *ti) | |
1170 | { | |
1171 | struct crypt_config *cc = ti->private; | |
1172 | ||
1173 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1174 | } | |
1175 | ||
1176 | /* Message interface | |
1177 | * key set <key> | |
1178 | * key wipe | |
1179 | */ | |
1180 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1181 | { | |
1182 | struct crypt_config *cc = ti->private; | |
1183 | ||
1184 | if (argc < 2) | |
1185 | goto error; | |
1186 | ||
1187 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1188 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1189 | DMWARN("not suspended during key manipulation."); | |
1190 | return -EINVAL; | |
1191 | } | |
1192 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1193 | return crypt_set_key(cc, argv[2]); | |
1194 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1195 | return crypt_wipe_key(cc); | |
1196 | } | |
1197 | ||
1198 | error: | |
1199 | DMWARN("unrecognised message received."); | |
1200 | return -EINVAL; | |
1201 | } | |
1202 | ||
1da177e4 LT |
1203 | static struct target_type crypt_target = { |
1204 | .name = "crypt", | |
46b47730 | 1205 | .version= {1, 5, 0}, |
1da177e4 LT |
1206 | .module = THIS_MODULE, |
1207 | .ctr = crypt_ctr, | |
1208 | .dtr = crypt_dtr, | |
1209 | .map = crypt_map, | |
1210 | .status = crypt_status, | |
e48d4bbf MB |
1211 | .postsuspend = crypt_postsuspend, |
1212 | .preresume = crypt_preresume, | |
1213 | .resume = crypt_resume, | |
1214 | .message = crypt_message, | |
1da177e4 LT |
1215 | }; |
1216 | ||
1217 | static int __init dm_crypt_init(void) | |
1218 | { | |
1219 | int r; | |
1220 | ||
028867ac | 1221 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1222 | if (!_crypt_io_pool) |
1223 | return -ENOMEM; | |
1224 | ||
1da177e4 LT |
1225 | r = dm_register_target(&crypt_target); |
1226 | if (r < 0) { | |
72d94861 | 1227 | DMERR("register failed %d", r); |
9934a8be | 1228 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1229 | } |
1230 | ||
1da177e4 LT |
1231 | return r; |
1232 | } | |
1233 | ||
1234 | static void __exit dm_crypt_exit(void) | |
1235 | { | |
1236 | int r = dm_unregister_target(&crypt_target); | |
1237 | ||
1238 | if (r < 0) | |
72d94861 | 1239 | DMERR("unregister failed %d", r); |
1da177e4 | 1240 | |
1da177e4 LT |
1241 | kmem_cache_destroy(_crypt_io_pool); |
1242 | } | |
1243 | ||
1244 | module_init(dm_crypt_init); | |
1245 | module_exit(dm_crypt_exit); | |
1246 | ||
1247 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1248 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1249 | MODULE_LICENSE("GPL"); |