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]; | |
3a7f6c99 | 126 | struct crypto_ablkcipher *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 | 219 | if (crypto_cipher_blocksize(essiv_tfm) != |
3a7f6c99 | 220 | crypto_ablkcipher_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 | { | |
3a7f6c99 | 257 | unsigned bs = crypto_ablkcipher_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 | ||
d469f841 MB |
321 | static void crypt_convert_init(struct crypt_config *cc, |
322 | struct convert_context *ctx, | |
323 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 324 | sector_t sector) |
1da177e4 LT |
325 | { |
326 | ctx->bio_in = bio_in; | |
327 | ctx->bio_out = bio_out; | |
328 | ctx->offset_in = 0; | |
329 | ctx->offset_out = 0; | |
330 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
331 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
332 | ctx->sector = sector + cc->iv_offset; | |
43d69034 MB |
333 | init_completion(&ctx->restart); |
334 | /* | |
335 | * Crypto operation can be asynchronous, | |
336 | * ctx->pending is increased after request submission. | |
337 | * We need to ensure that we don't call the crypt finish | |
338 | * operation before pending got incremented | |
339 | * (dependent on crypt submission return code). | |
340 | */ | |
341 | atomic_set(&ctx->pending, 2); | |
1da177e4 LT |
342 | } |
343 | ||
01482b76 | 344 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
345 | struct convert_context *ctx, |
346 | struct ablkcipher_request *req) | |
01482b76 MB |
347 | { |
348 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
349 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
3a7f6c99 MB |
350 | struct dm_crypt_request *dmreq; |
351 | u8 *iv; | |
352 | int r = 0; | |
353 | ||
354 | dmreq = (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
355 | iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), | |
356 | crypto_ablkcipher_alignmask(cc->tfm) + 1); | |
01482b76 | 357 | |
3a7f6c99 MB |
358 | sg_init_table(&dmreq->sg_in, 1); |
359 | sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
360 | bv_in->bv_offset + ctx->offset_in); |
361 | ||
3a7f6c99 MB |
362 | sg_init_table(&dmreq->sg_out, 1); |
363 | sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
364 | bv_out->bv_offset + ctx->offset_out); |
365 | ||
366 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
367 | if (ctx->offset_in >= bv_in->bv_len) { | |
368 | ctx->offset_in = 0; | |
369 | ctx->idx_in++; | |
370 | } | |
371 | ||
372 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
373 | if (ctx->offset_out >= bv_out->bv_len) { | |
374 | ctx->offset_out = 0; | |
375 | ctx->idx_out++; | |
376 | } | |
377 | ||
3a7f6c99 MB |
378 | if (cc->iv_gen_ops) { |
379 | r = cc->iv_gen_ops->generator(cc, iv, ctx->sector); | |
380 | if (r < 0) | |
381 | return r; | |
382 | } | |
383 | ||
384 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
385 | 1 << SECTOR_SHIFT, iv); | |
386 | ||
387 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
388 | r = crypto_ablkcipher_encrypt(req); | |
389 | else | |
390 | r = crypto_ablkcipher_decrypt(req); | |
391 | ||
392 | return r; | |
01482b76 MB |
393 | } |
394 | ||
95497a96 MB |
395 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
396 | int error); | |
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); | |
95497a96 MB |
402 | ablkcipher_request_set_tfm(cc->req, cc->tfm); |
403 | ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | | |
404 | CRYPTO_TFM_REQ_MAY_SLEEP, | |
405 | kcryptd_async_done, ctx); | |
ddd42edf MB |
406 | } |
407 | ||
1da177e4 LT |
408 | /* |
409 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
410 | */ | |
411 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 412 | struct convert_context *ctx) |
1da177e4 LT |
413 | { |
414 | int r = 0; | |
415 | ||
416 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
417 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
1da177e4 | 418 | |
3a7f6c99 MB |
419 | crypt_alloc_req(cc, ctx); |
420 | ||
421 | r = crypt_convert_block(cc, ctx, cc->req); | |
422 | ||
423 | switch (r) { | |
424 | case -EBUSY: | |
425 | wait_for_completion(&ctx->restart); | |
426 | INIT_COMPLETION(ctx->restart); | |
427 | /* fall through*/ | |
428 | case -EINPROGRESS: | |
429 | atomic_inc(&ctx->pending); | |
430 | cc->req = NULL; | |
431 | r = 0; | |
432 | /* fall through*/ | |
433 | case 0: | |
434 | ctx->sector++; | |
435 | continue; | |
436 | } | |
437 | ||
438 | break; | |
1da177e4 LT |
439 | } |
440 | ||
43d69034 MB |
441 | /* |
442 | * If there are pending crypto operation run async | |
443 | * code. Otherwise process return code synchronously. | |
444 | * The step of 2 ensures that async finish doesn't | |
445 | * call crypto finish too early. | |
446 | */ | |
447 | if (atomic_sub_return(2, &ctx->pending)) | |
448 | return -EINPROGRESS; | |
449 | ||
1da177e4 LT |
450 | return r; |
451 | } | |
452 | ||
d469f841 MB |
453 | static void dm_crypt_bio_destructor(struct bio *bio) |
454 | { | |
028867ac | 455 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
456 | struct crypt_config *cc = io->target->private; |
457 | ||
458 | bio_free(bio, cc->bs); | |
d469f841 | 459 | } |
6a24c718 | 460 | |
1da177e4 LT |
461 | /* |
462 | * Generate a new unfragmented bio with the given size | |
463 | * This should never violate the device limitations | |
464 | * May return a smaller bio when running out of pages | |
465 | */ | |
028867ac | 466 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 467 | { |
027581f3 | 468 | struct crypt_config *cc = io->target->private; |
8b004457 | 469 | struct bio *clone; |
1da177e4 | 470 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 471 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
472 | unsigned i, len; |
473 | struct page *page; | |
1da177e4 | 474 | |
2f9941b6 | 475 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 476 | if (!clone) |
1da177e4 | 477 | return NULL; |
1da177e4 | 478 | |
027581f3 | 479 | clone_init(io, clone); |
6a24c718 | 480 | |
f97380bc | 481 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
482 | page = mempool_alloc(cc->page_pool, gfp_mask); |
483 | if (!page) | |
1da177e4 LT |
484 | break; |
485 | ||
486 | /* | |
487 | * if additional pages cannot be allocated without waiting, | |
488 | * return a partially allocated bio, the caller will then try | |
489 | * to allocate additional bios while submitting this partial bio | |
490 | */ | |
f97380bc | 491 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
492 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
493 | ||
91e10625 MB |
494 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
495 | ||
496 | if (!bio_add_page(clone, page, len, 0)) { | |
497 | mempool_free(page, cc->page_pool); | |
498 | break; | |
499 | } | |
1da177e4 | 500 | |
91e10625 | 501 | size -= len; |
1da177e4 LT |
502 | } |
503 | ||
8b004457 MB |
504 | if (!clone->bi_size) { |
505 | bio_put(clone); | |
1da177e4 LT |
506 | return NULL; |
507 | } | |
508 | ||
8b004457 | 509 | return clone; |
1da177e4 LT |
510 | } |
511 | ||
644bd2f0 | 512 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 513 | { |
644bd2f0 | 514 | unsigned int i; |
1da177e4 LT |
515 | struct bio_vec *bv; |
516 | ||
644bd2f0 | 517 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 518 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
519 | BUG_ON(!bv->bv_page); |
520 | mempool_free(bv->bv_page, cc->page_pool); | |
521 | bv->bv_page = NULL; | |
522 | } | |
523 | } | |
524 | ||
525 | /* | |
526 | * One of the bios was finished. Check for completion of | |
527 | * the whole request and correctly clean up the buffer. | |
528 | */ | |
5742fd77 | 529 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 530 | { |
5742fd77 | 531 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
532 | |
533 | if (!atomic_dec_and_test(&io->pending)) | |
534 | return; | |
535 | ||
6712ecf8 | 536 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
537 | mempool_free(io, cc->io_pool); |
538 | } | |
539 | ||
540 | /* | |
cabf08e4 | 541 | * kcryptd/kcryptd_io: |
1da177e4 LT |
542 | * |
543 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 544 | * interrupt context. |
cabf08e4 MB |
545 | * |
546 | * kcryptd performs the actual encryption or decryption. | |
547 | * | |
548 | * kcryptd_io performs the IO submission. | |
549 | * | |
550 | * They must be separated as otherwise the final stages could be | |
551 | * starved by new requests which can block in the first stages due | |
552 | * to memory allocation. | |
1da177e4 | 553 | */ |
6712ecf8 | 554 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 555 | { |
028867ac | 556 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 557 | struct crypt_config *cc = io->target->private; |
ee7a491e | 558 | unsigned rw = bio_data_dir(clone); |
8b004457 | 559 | |
adfe4770 MB |
560 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
561 | error = -EIO; | |
562 | ||
8b004457 | 563 | /* |
6712ecf8 | 564 | * free the processed pages |
8b004457 | 565 | */ |
ee7a491e | 566 | if (rw == WRITE) |
644bd2f0 | 567 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
568 | |
569 | bio_put(clone); | |
8b004457 | 570 | |
ee7a491e MB |
571 | if (rw == READ && !error) { |
572 | kcryptd_queue_crypt(io); | |
573 | return; | |
574 | } | |
5742fd77 MB |
575 | |
576 | if (unlikely(error)) | |
577 | io->error = error; | |
578 | ||
579 | crypt_dec_pending(io); | |
8b004457 MB |
580 | } |
581 | ||
028867ac | 582 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
583 | { |
584 | struct crypt_config *cc = io->target->private; | |
585 | ||
586 | clone->bi_private = io; | |
587 | clone->bi_end_io = crypt_endio; | |
588 | clone->bi_bdev = cc->dev->bdev; | |
589 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 590 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
591 | } |
592 | ||
4e4eef64 | 593 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
594 | { |
595 | struct crypt_config *cc = io->target->private; | |
596 | struct bio *base_bio = io->base_bio; | |
597 | struct bio *clone; | |
93e605c2 MB |
598 | |
599 | atomic_inc(&io->pending); | |
8b004457 MB |
600 | |
601 | /* | |
602 | * The block layer might modify the bvec array, so always | |
603 | * copy the required bvecs because we need the original | |
604 | * one in order to decrypt the whole bio data *afterwards*. | |
605 | */ | |
6a24c718 | 606 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 607 | if (unlikely(!clone)) { |
5742fd77 MB |
608 | io->error = -ENOMEM; |
609 | crypt_dec_pending(io); | |
23541d2d | 610 | return; |
93e605c2 | 611 | } |
8b004457 MB |
612 | |
613 | clone_init(io, clone); | |
614 | clone->bi_idx = 0; | |
615 | clone->bi_vcnt = bio_segments(base_bio); | |
616 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 617 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
618 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
619 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 620 | |
93e605c2 | 621 | generic_make_request(clone); |
8b004457 MB |
622 | } |
623 | ||
4e4eef64 MB |
624 | static void kcryptd_io_write(struct dm_crypt_io *io) |
625 | { | |
95497a96 MB |
626 | struct bio *clone = io->ctx.bio_out; |
627 | ||
628 | generic_make_request(clone); | |
4e4eef64 MB |
629 | } |
630 | ||
395b167c AK |
631 | static void kcryptd_io(struct work_struct *work) |
632 | { | |
633 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
634 | ||
635 | if (bio_data_dir(io->base_bio) == READ) | |
636 | kcryptd_io_read(io); | |
637 | else | |
638 | kcryptd_io_write(io); | |
639 | } | |
640 | ||
641 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
642 | { | |
643 | struct crypt_config *cc = io->target->private; | |
644 | ||
645 | INIT_WORK(&io->work, kcryptd_io); | |
646 | queue_work(cc->io_queue, &io->work); | |
647 | } | |
648 | ||
95497a96 MB |
649 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
650 | int error, int async) | |
4e4eef64 | 651 | { |
dec1cedf MB |
652 | struct bio *clone = io->ctx.bio_out; |
653 | struct crypt_config *cc = io->target->private; | |
654 | ||
655 | if (unlikely(error < 0)) { | |
656 | crypt_free_buffer_pages(cc, clone); | |
657 | bio_put(clone); | |
658 | io->error = -EIO; | |
dec1cedf MB |
659 | return; |
660 | } | |
661 | ||
662 | /* crypt_convert should have filled the clone bio */ | |
663 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
664 | ||
665 | clone->bi_sector = cc->start + io->sector; | |
666 | io->sector += bio_sectors(clone); | |
899c95d3 | 667 | |
95497a96 MB |
668 | if (async) |
669 | kcryptd_queue_io(io); | |
670 | else { | |
671 | atomic_inc(&io->pending); | |
672 | generic_make_request(clone); | |
673 | } | |
4e4eef64 MB |
674 | } |
675 | ||
84131db6 | 676 | static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io) |
8b004457 MB |
677 | { |
678 | struct crypt_config *cc = io->target->private; | |
8b004457 | 679 | struct bio *clone; |
dec1cedf MB |
680 | unsigned remaining = io->base_bio->bi_size; |
681 | int r; | |
8b004457 | 682 | |
93e605c2 MB |
683 | /* |
684 | * The allocated buffers can be smaller than the whole bio, | |
685 | * so repeat the whole process until all the data can be handled. | |
686 | */ | |
687 | while (remaining) { | |
f97380bc | 688 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 689 | if (unlikely(!clone)) { |
5742fd77 | 690 | io->error = -ENOMEM; |
23541d2d MB |
691 | return; |
692 | } | |
93e605c2 | 693 | |
53017030 MB |
694 | io->ctx.bio_out = clone; |
695 | io->ctx.idx_out = 0; | |
93e605c2 | 696 | |
dec1cedf | 697 | remaining -= clone->bi_size; |
93e605c2 | 698 | |
dec1cedf | 699 | r = crypt_convert(cc, &io->ctx); |
f97380bc | 700 | |
3a7f6c99 MB |
701 | if (r != -EINPROGRESS) { |
702 | kcryptd_crypt_write_io_submit(io, r, 0); | |
703 | if (unlikely(r < 0)) | |
704 | return; | |
705 | } else | |
706 | atomic_inc(&io->pending); | |
93e605c2 | 707 | |
93e605c2 | 708 | /* out of memory -> run queues */ |
dec1cedf | 709 | if (unlikely(remaining)) |
98221eb7 | 710 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 711 | } |
8b004457 MB |
712 | } |
713 | ||
84131db6 MB |
714 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
715 | { | |
716 | struct crypt_config *cc = io->target->private; | |
717 | ||
899c95d3 MB |
718 | /* |
719 | * Prevent io from disappearing until this function completes. | |
720 | */ | |
84131db6 MB |
721 | atomic_inc(&io->pending); |
722 | ||
723 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector); | |
724 | kcryptd_crypt_write_convert_loop(io); | |
899c95d3 MB |
725 | |
726 | crypt_dec_pending(io); | |
84131db6 MB |
727 | } |
728 | ||
4e4eef64 | 729 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
730 | { |
731 | if (unlikely(error < 0)) | |
732 | io->error = -EIO; | |
733 | ||
734 | crypt_dec_pending(io); | |
735 | } | |
736 | ||
4e4eef64 | 737 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
738 | { |
739 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 740 | int r = 0; |
1da177e4 | 741 | |
3a7f6c99 MB |
742 | atomic_inc(&io->pending); |
743 | ||
53017030 | 744 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 745 | io->sector); |
1da177e4 | 746 | |
5742fd77 MB |
747 | r = crypt_convert(cc, &io->ctx); |
748 | ||
3a7f6c99 MB |
749 | if (r != -EINPROGRESS) |
750 | kcryptd_crypt_read_done(io, r); | |
751 | ||
752 | crypt_dec_pending(io); | |
1da177e4 LT |
753 | } |
754 | ||
95497a96 MB |
755 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
756 | int error) | |
757 | { | |
758 | struct convert_context *ctx = async_req->data; | |
759 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); | |
760 | struct crypt_config *cc = io->target->private; | |
761 | ||
762 | if (error == -EINPROGRESS) { | |
763 | complete(&ctx->restart); | |
764 | return; | |
765 | } | |
766 | ||
767 | mempool_free(ablkcipher_request_cast(async_req), cc->req_pool); | |
768 | ||
769 | if (!atomic_dec_and_test(&ctx->pending)) | |
770 | return; | |
771 | ||
772 | if (bio_data_dir(io->base_bio) == READ) | |
773 | kcryptd_crypt_read_done(io, error); | |
774 | else | |
775 | kcryptd_crypt_write_io_submit(io, error, 1); | |
776 | } | |
777 | ||
395b167c | 778 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 779 | { |
028867ac | 780 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 781 | |
cabf08e4 | 782 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 783 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 784 | else |
395b167c | 785 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
786 | } |
787 | ||
395b167c | 788 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 789 | { |
395b167c | 790 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 791 | |
395b167c AK |
792 | INIT_WORK(&io->work, kcryptd_crypt); |
793 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
794 | } |
795 | ||
796 | /* | |
797 | * Decode key from its hex representation | |
798 | */ | |
799 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
800 | { | |
801 | char buffer[3]; | |
802 | char *endp; | |
803 | unsigned int i; | |
804 | ||
805 | buffer[2] = '\0'; | |
806 | ||
8b004457 | 807 | for (i = 0; i < size; i++) { |
1da177e4 LT |
808 | buffer[0] = *hex++; |
809 | buffer[1] = *hex++; | |
810 | ||
811 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
812 | ||
813 | if (endp != &buffer[2]) | |
814 | return -EINVAL; | |
815 | } | |
816 | ||
817 | if (*hex != '\0') | |
818 | return -EINVAL; | |
819 | ||
820 | return 0; | |
821 | } | |
822 | ||
823 | /* | |
824 | * Encode key into its hex representation | |
825 | */ | |
826 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
827 | { | |
828 | unsigned int i; | |
829 | ||
8b004457 | 830 | for (i = 0; i < size; i++) { |
1da177e4 LT |
831 | sprintf(hex, "%02x", *key); |
832 | hex += 2; | |
833 | key++; | |
834 | } | |
835 | } | |
836 | ||
e48d4bbf MB |
837 | static int crypt_set_key(struct crypt_config *cc, char *key) |
838 | { | |
839 | unsigned key_size = strlen(key) >> 1; | |
840 | ||
841 | if (cc->key_size && cc->key_size != key_size) | |
842 | return -EINVAL; | |
843 | ||
844 | cc->key_size = key_size; /* initial settings */ | |
845 | ||
846 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 847 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
848 | return -EINVAL; |
849 | ||
850 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
851 | ||
852 | return 0; | |
853 | } | |
854 | ||
855 | static int crypt_wipe_key(struct crypt_config *cc) | |
856 | { | |
857 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
858 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
859 | return 0; | |
860 | } | |
861 | ||
1da177e4 LT |
862 | /* |
863 | * Construct an encryption mapping: | |
864 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
865 | */ | |
866 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
867 | { | |
868 | struct crypt_config *cc; | |
3a7f6c99 | 869 | struct crypto_ablkcipher *tfm; |
1da177e4 LT |
870 | char *tmp; |
871 | char *cipher; | |
872 | char *chainmode; | |
873 | char *ivmode; | |
874 | char *ivopts; | |
1da177e4 | 875 | unsigned int key_size; |
4ee218cd | 876 | unsigned long long tmpll; |
1da177e4 LT |
877 | |
878 | if (argc != 5) { | |
72d94861 | 879 | ti->error = "Not enough arguments"; |
1da177e4 LT |
880 | return -EINVAL; |
881 | } | |
882 | ||
883 | tmp = argv[0]; | |
884 | cipher = strsep(&tmp, "-"); | |
885 | chainmode = strsep(&tmp, "-"); | |
886 | ivopts = strsep(&tmp, "-"); | |
887 | ivmode = strsep(&ivopts, ":"); | |
888 | ||
889 | if (tmp) | |
72d94861 | 890 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
891 | |
892 | key_size = strlen(argv[1]) >> 1; | |
893 | ||
e48d4bbf | 894 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
895 | if (cc == NULL) { |
896 | ti->error = | |
72d94861 | 897 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
898 | return -ENOMEM; |
899 | } | |
900 | ||
e48d4bbf | 901 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 902 | ti->error = "Error decoding key"; |
636d5786 | 903 | goto bad_cipher; |
1da177e4 LT |
904 | } |
905 | ||
906 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
907 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
908 | chainmode = "cbc"; | |
909 | ivmode = "plain"; | |
910 | } | |
911 | ||
d1806f6a HX |
912 | if (strcmp(chainmode, "ecb") && !ivmode) { |
913 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 914 | goto bad_cipher; |
1da177e4 LT |
915 | } |
916 | ||
d469f841 MB |
917 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
918 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 919 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 920 | goto bad_cipher; |
1da177e4 LT |
921 | } |
922 | ||
3a7f6c99 | 923 | tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0); |
d1806f6a | 924 | if (IS_ERR(tfm)) { |
72d94861 | 925 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 926 | goto bad_cipher; |
1da177e4 | 927 | } |
1da177e4 | 928 | |
d1806f6a HX |
929 | strcpy(cc->cipher, cipher); |
930 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
931 | cc->tfm = tfm; |
932 | ||
933 | /* | |
48527fa7 | 934 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
935 | * See comments at iv code |
936 | */ | |
937 | ||
938 | if (ivmode == NULL) | |
939 | cc->iv_gen_ops = NULL; | |
940 | else if (strcmp(ivmode, "plain") == 0) | |
941 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
942 | else if (strcmp(ivmode, "essiv") == 0) | |
943 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
944 | else if (strcmp(ivmode, "benbi") == 0) |
945 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
946 | else if (strcmp(ivmode, "null") == 0) |
947 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 948 | else { |
72d94861 | 949 | ti->error = "Invalid IV mode"; |
636d5786 | 950 | goto bad_ivmode; |
1da177e4 LT |
951 | } |
952 | ||
953 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
954 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 955 | goto bad_ivmode; |
1da177e4 | 956 | |
3a7f6c99 | 957 | cc->iv_size = crypto_ablkcipher_ivsize(tfm); |
d1806f6a | 958 | if (cc->iv_size) |
1da177e4 | 959 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 960 | cc->iv_size = max(cc->iv_size, |
d469f841 | 961 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 962 | else { |
1da177e4 | 963 | if (cc->iv_gen_ops) { |
72d94861 | 964 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
965 | if (cc->iv_gen_ops->dtr) |
966 | cc->iv_gen_ops->dtr(cc); | |
967 | cc->iv_gen_ops = NULL; | |
968 | } | |
969 | } | |
970 | ||
93d2341c | 971 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 972 | if (!cc->io_pool) { |
72d94861 | 973 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 974 | goto bad_slab_pool; |
1da177e4 LT |
975 | } |
976 | ||
ddd42edf | 977 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
3a7f6c99 | 978 | cc->dmreq_start += crypto_ablkcipher_reqsize(tfm); |
ddd42edf | 979 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); |
3a7f6c99 MB |
980 | cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) & |
981 | ~(crypto_tfm_ctx_alignment() - 1); | |
ddd42edf MB |
982 | |
983 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
984 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
985 | if (!cc->req_pool) { | |
986 | ti->error = "Cannot allocate crypt request mempool"; | |
987 | goto bad_req_pool; | |
988 | } | |
989 | cc->req = NULL; | |
990 | ||
a19b27ce | 991 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 992 | if (!cc->page_pool) { |
72d94861 | 993 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 994 | goto bad_page_pool; |
1da177e4 LT |
995 | } |
996 | ||
5972511b | 997 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
998 | if (!cc->bs) { |
999 | ti->error = "Cannot allocate crypt bioset"; | |
1000 | goto bad_bs; | |
1001 | } | |
1002 | ||
3a7f6c99 | 1003 | if (crypto_ablkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 1004 | ti->error = "Error setting key"; |
636d5786 | 1005 | goto bad_device; |
1da177e4 LT |
1006 | } |
1007 | ||
4ee218cd | 1008 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 1009 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 1010 | goto bad_device; |
1da177e4 | 1011 | } |
4ee218cd | 1012 | cc->iv_offset = tmpll; |
1da177e4 | 1013 | |
4ee218cd | 1014 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1015 | ti->error = "Invalid device sector"; |
636d5786 | 1016 | goto bad_device; |
1da177e4 | 1017 | } |
4ee218cd | 1018 | cc->start = tmpll; |
1da177e4 LT |
1019 | |
1020 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 1021 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 1022 | ti->error = "Device lookup failed"; |
636d5786 | 1023 | goto bad_device; |
1da177e4 LT |
1024 | } |
1025 | ||
1026 | if (ivmode && cc->iv_gen_ops) { | |
1027 | if (ivopts) | |
1028 | *(ivopts - 1) = ':'; | |
1029 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
1030 | if (!cc->iv_mode) { | |
72d94861 | 1031 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 1032 | goto bad_ivmode_string; |
1da177e4 LT |
1033 | } |
1034 | strcpy(cc->iv_mode, ivmode); | |
1035 | } else | |
1036 | cc->iv_mode = NULL; | |
1037 | ||
cabf08e4 MB |
1038 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
1039 | if (!cc->io_queue) { | |
1040 | ti->error = "Couldn't create kcryptd io queue"; | |
1041 | goto bad_io_queue; | |
1042 | } | |
1043 | ||
1044 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
1045 | if (!cc->crypt_queue) { | |
9934a8be | 1046 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 1047 | goto bad_crypt_queue; |
9934a8be MB |
1048 | } |
1049 | ||
1da177e4 LT |
1050 | ti->private = cc; |
1051 | return 0; | |
1052 | ||
cabf08e4 MB |
1053 | bad_crypt_queue: |
1054 | destroy_workqueue(cc->io_queue); | |
1055 | bad_io_queue: | |
9934a8be | 1056 | kfree(cc->iv_mode); |
636d5786 | 1057 | bad_ivmode_string: |
55b42c5a | 1058 | dm_put_device(ti, cc->dev); |
636d5786 | 1059 | bad_device: |
6a24c718 MB |
1060 | bioset_free(cc->bs); |
1061 | bad_bs: | |
1da177e4 | 1062 | mempool_destroy(cc->page_pool); |
636d5786 | 1063 | bad_page_pool: |
ddd42edf MB |
1064 | mempool_destroy(cc->req_pool); |
1065 | bad_req_pool: | |
1da177e4 | 1066 | mempool_destroy(cc->io_pool); |
636d5786 | 1067 | bad_slab_pool: |
1da177e4 LT |
1068 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1069 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 1070 | bad_ivmode: |
3a7f6c99 | 1071 | crypto_free_ablkcipher(tfm); |
636d5786 | 1072 | bad_cipher: |
9d3520a3 SR |
1073 | /* Must zero key material before freeing */ |
1074 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1075 | kfree(cc); |
1076 | return -EINVAL; | |
1077 | } | |
1078 | ||
1079 | static void crypt_dtr(struct dm_target *ti) | |
1080 | { | |
1081 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1082 | ||
cabf08e4 MB |
1083 | destroy_workqueue(cc->io_queue); |
1084 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1085 | |
ddd42edf MB |
1086 | if (cc->req) |
1087 | mempool_free(cc->req, cc->req_pool); | |
1088 | ||
6a24c718 | 1089 | bioset_free(cc->bs); |
1da177e4 | 1090 | mempool_destroy(cc->page_pool); |
ddd42edf | 1091 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1092 | mempool_destroy(cc->io_pool); |
1093 | ||
990a8baf | 1094 | kfree(cc->iv_mode); |
1da177e4 LT |
1095 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1096 | cc->iv_gen_ops->dtr(cc); | |
3a7f6c99 | 1097 | crypto_free_ablkcipher(cc->tfm); |
1da177e4 | 1098 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1099 | |
1100 | /* Must zero key material before freeing */ | |
1101 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
1102 | kfree(cc); |
1103 | } | |
1104 | ||
1da177e4 LT |
1105 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1106 | union map_info *map_context) | |
1107 | { | |
8b004457 | 1108 | struct crypt_config *cc = ti->private; |
028867ac | 1109 | struct dm_crypt_io *io; |
1da177e4 | 1110 | |
e48d4bbf | 1111 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 1112 | io->target = ti; |
8b004457 | 1113 | io->base_bio = bio; |
0c395b0f | 1114 | io->sector = bio->bi_sector - ti->begin; |
cabf08e4 | 1115 | io->error = 0; |
93e605c2 | 1116 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
1117 | |
1118 | if (bio_data_dir(io->base_bio) == READ) | |
1119 | kcryptd_queue_io(io); | |
1120 | else | |
1121 | kcryptd_queue_crypt(io); | |
1da177e4 | 1122 | |
d2a7ad29 | 1123 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1124 | } |
1125 | ||
1126 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1127 | char *result, unsigned int maxlen) | |
1128 | { | |
1129 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1130 | unsigned int sz = 0; |
1131 | ||
1132 | switch (type) { | |
1133 | case STATUSTYPE_INFO: | |
1134 | result[0] = '\0'; | |
1135 | break; | |
1136 | ||
1137 | case STATUSTYPE_TABLE: | |
1da177e4 | 1138 | if (cc->iv_mode) |
37af6560 CS |
1139 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1140 | cc->iv_mode); | |
1da177e4 | 1141 | else |
37af6560 | 1142 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1143 | |
1144 | if (cc->key_size > 0) { | |
1145 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1146 | return -ENOMEM; | |
1147 | ||
1148 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1149 | sz += cc->key_size << 1; | |
1150 | } else { | |
1151 | if (sz >= maxlen) | |
1152 | return -ENOMEM; | |
1153 | result[sz++] = '-'; | |
1154 | } | |
1155 | ||
4ee218cd AM |
1156 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1157 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1158 | break; |
1159 | } | |
1160 | return 0; | |
1161 | } | |
1162 | ||
e48d4bbf MB |
1163 | static void crypt_postsuspend(struct dm_target *ti) |
1164 | { | |
1165 | struct crypt_config *cc = ti->private; | |
1166 | ||
1167 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1168 | } | |
1169 | ||
1170 | static int crypt_preresume(struct dm_target *ti) | |
1171 | { | |
1172 | struct crypt_config *cc = ti->private; | |
1173 | ||
1174 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1175 | DMERR("aborting resume - crypt key is not set."); | |
1176 | return -EAGAIN; | |
1177 | } | |
1178 | ||
1179 | return 0; | |
1180 | } | |
1181 | ||
1182 | static void crypt_resume(struct dm_target *ti) | |
1183 | { | |
1184 | struct crypt_config *cc = ti->private; | |
1185 | ||
1186 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1187 | } | |
1188 | ||
1189 | /* Message interface | |
1190 | * key set <key> | |
1191 | * key wipe | |
1192 | */ | |
1193 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1194 | { | |
1195 | struct crypt_config *cc = ti->private; | |
1196 | ||
1197 | if (argc < 2) | |
1198 | goto error; | |
1199 | ||
1200 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1201 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1202 | DMWARN("not suspended during key manipulation."); | |
1203 | return -EINVAL; | |
1204 | } | |
1205 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1206 | return crypt_set_key(cc, argv[2]); | |
1207 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1208 | return crypt_wipe_key(cc); | |
1209 | } | |
1210 | ||
1211 | error: | |
1212 | DMWARN("unrecognised message received."); | |
1213 | return -EINVAL; | |
1214 | } | |
1215 | ||
1da177e4 LT |
1216 | static struct target_type crypt_target = { |
1217 | .name = "crypt", | |
46b47730 | 1218 | .version= {1, 5, 0}, |
1da177e4 LT |
1219 | .module = THIS_MODULE, |
1220 | .ctr = crypt_ctr, | |
1221 | .dtr = crypt_dtr, | |
1222 | .map = crypt_map, | |
1223 | .status = crypt_status, | |
e48d4bbf MB |
1224 | .postsuspend = crypt_postsuspend, |
1225 | .preresume = crypt_preresume, | |
1226 | .resume = crypt_resume, | |
1227 | .message = crypt_message, | |
1da177e4 LT |
1228 | }; |
1229 | ||
1230 | static int __init dm_crypt_init(void) | |
1231 | { | |
1232 | int r; | |
1233 | ||
028867ac | 1234 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1235 | if (!_crypt_io_pool) |
1236 | return -ENOMEM; | |
1237 | ||
1da177e4 LT |
1238 | r = dm_register_target(&crypt_target); |
1239 | if (r < 0) { | |
72d94861 | 1240 | DMERR("register failed %d", r); |
9934a8be | 1241 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1242 | } |
1243 | ||
1da177e4 LT |
1244 | return r; |
1245 | } | |
1246 | ||
1247 | static void __exit dm_crypt_exit(void) | |
1248 | { | |
1249 | int r = dm_unregister_target(&crypt_target); | |
1250 | ||
1251 | if (r < 0) | |
72d94861 | 1252 | DMERR("unregister failed %d", r); |
1da177e4 | 1253 | |
1da177e4 LT |
1254 | kmem_cache_destroy(_crypt_io_pool); |
1255 | } | |
1256 | ||
1257 | module_init(dm_crypt_init); | |
1258 | module_exit(dm_crypt_exit); | |
1259 | ||
1260 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1261 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1262 | MODULE_LICENSE("GPL"); |