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; | |
55 | }; | |
56 | ||
1da177e4 LT |
57 | struct crypt_config; |
58 | ||
59 | struct crypt_iv_operations { | |
60 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 61 | const char *opts); |
1da177e4 LT |
62 | void (*dtr)(struct crypt_config *cc); |
63 | const char *(*status)(struct crypt_config *cc); | |
64 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
65 | }; | |
66 | ||
67 | /* | |
68 | * Crypt: maps a linear range of a block device | |
69 | * and encrypts / decrypts at the same time. | |
70 | */ | |
e48d4bbf | 71 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
72 | struct crypt_config { |
73 | struct dm_dev *dev; | |
74 | sector_t start; | |
75 | ||
76 | /* | |
77 | * pool for per bio private data and | |
78 | * for encryption buffer pages | |
79 | */ | |
80 | mempool_t *io_pool; | |
81 | mempool_t *page_pool; | |
6a24c718 | 82 | struct bio_set *bs; |
1da177e4 | 83 | |
cabf08e4 MB |
84 | struct workqueue_struct *io_queue; |
85 | struct workqueue_struct *crypt_queue; | |
1da177e4 LT |
86 | /* |
87 | * crypto related data | |
88 | */ | |
89 | struct crypt_iv_operations *iv_gen_ops; | |
90 | char *iv_mode; | |
79066ad3 HX |
91 | union { |
92 | struct crypto_cipher *essiv_tfm; | |
93 | int benbi_shift; | |
94 | } iv_gen_private; | |
1da177e4 LT |
95 | sector_t iv_offset; |
96 | unsigned int iv_size; | |
97 | ||
d1806f6a HX |
98 | char cipher[CRYPTO_MAX_ALG_NAME]; |
99 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
100 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 101 | unsigned long flags; |
1da177e4 LT |
102 | unsigned int key_size; |
103 | u8 key[0]; | |
104 | }; | |
105 | ||
6a24c718 | 106 | #define MIN_IOS 16 |
1da177e4 LT |
107 | #define MIN_POOL_PAGES 32 |
108 | #define MIN_BIO_PAGES 8 | |
109 | ||
e18b890b | 110 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 111 | |
028867ac | 112 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 113 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 114 | |
1da177e4 LT |
115 | /* |
116 | * Different IV generation algorithms: | |
117 | * | |
3c164bd8 | 118 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 119 | * number, padded with zeros if necessary. |
1da177e4 | 120 | * |
3c164bd8 RS |
121 | * essiv: "encrypted sector|salt initial vector", the sector number is |
122 | * encrypted with the bulk cipher using a salt as key. The salt | |
123 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 124 | * |
48527fa7 RS |
125 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
126 | * (needed for LRW-32-AES and possible other narrow block modes) | |
127 | * | |
46b47730 LN |
128 | * null: the initial vector is always zero. Provides compatibility with |
129 | * obsolete loop_fish2 devices. Do not use for new devices. | |
130 | * | |
1da177e4 LT |
131 | * plumb: unimplemented, see: |
132 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
133 | */ | |
134 | ||
135 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
136 | { | |
137 | memset(iv, 0, cc->iv_size); | |
138 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
139 | ||
140 | return 0; | |
141 | } | |
142 | ||
143 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 144 | const char *opts) |
1da177e4 | 145 | { |
d1806f6a | 146 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
147 | struct crypto_hash *hash_tfm; |
148 | struct hash_desc desc; | |
1da177e4 LT |
149 | struct scatterlist sg; |
150 | unsigned int saltsize; | |
151 | u8 *salt; | |
d1806f6a | 152 | int err; |
1da177e4 LT |
153 | |
154 | if (opts == NULL) { | |
72d94861 | 155 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
156 | return -EINVAL; |
157 | } | |
158 | ||
159 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
160 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
161 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 162 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 163 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
164 | } |
165 | ||
35058687 | 166 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
167 | salt = kmalloc(saltsize, GFP_KERNEL); |
168 | if (salt == NULL) { | |
72d94861 | 169 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 170 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
171 | return -ENOMEM; |
172 | } | |
173 | ||
68e3f5dd | 174 | sg_init_one(&sg, cc->key, cc->key_size); |
35058687 HX |
175 | desc.tfm = hash_tfm; |
176 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
177 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
178 | crypto_free_hash(hash_tfm); | |
179 | ||
180 | if (err) { | |
181 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 182 | kfree(salt); |
35058687 HX |
183 | return err; |
184 | } | |
1da177e4 LT |
185 | |
186 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
187 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
188 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 189 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 190 | kfree(salt); |
d1806f6a | 191 | return PTR_ERR(essiv_tfm); |
1da177e4 | 192 | } |
d1806f6a HX |
193 | if (crypto_cipher_blocksize(essiv_tfm) != |
194 | crypto_blkcipher_ivsize(cc->tfm)) { | |
72d94861 | 195 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 196 | "not match IV size of block cipher"; |
d1806f6a | 197 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
198 | kfree(salt); |
199 | return -EINVAL; | |
200 | } | |
d1806f6a HX |
201 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
202 | if (err) { | |
72d94861 | 203 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 204 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 205 | kfree(salt); |
d1806f6a | 206 | return err; |
1da177e4 LT |
207 | } |
208 | kfree(salt); | |
209 | ||
79066ad3 | 210 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
211 | return 0; |
212 | } | |
213 | ||
214 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
215 | { | |
79066ad3 HX |
216 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
217 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
218 | } |
219 | ||
220 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
221 | { | |
1da177e4 LT |
222 | memset(iv, 0, cc->iv_size); |
223 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 224 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
225 | return 0; |
226 | } | |
227 | ||
48527fa7 RS |
228 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
229 | const char *opts) | |
230 | { | |
231 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); | |
f0d1b0b3 | 232 | int log = ilog2(bs); |
48527fa7 RS |
233 | |
234 | /* we need to calculate how far we must shift the sector count | |
235 | * to get the cipher block count, we use this shift in _gen */ | |
236 | ||
237 | if (1 << log != bs) { | |
238 | ti->error = "cypher blocksize is not a power of 2"; | |
239 | return -EINVAL; | |
240 | } | |
241 | ||
242 | if (log > 9) { | |
243 | ti->error = "cypher blocksize is > 512"; | |
244 | return -EINVAL; | |
245 | } | |
246 | ||
79066ad3 | 247 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
248 | |
249 | return 0; | |
250 | } | |
251 | ||
252 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
253 | { | |
48527fa7 RS |
254 | } |
255 | ||
256 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
257 | { | |
79066ad3 HX |
258 | __be64 val; |
259 | ||
48527fa7 | 260 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
261 | |
262 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
263 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 264 | |
1da177e4 LT |
265 | return 0; |
266 | } | |
267 | ||
46b47730 LN |
268 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
269 | { | |
270 | memset(iv, 0, cc->iv_size); | |
271 | ||
272 | return 0; | |
273 | } | |
274 | ||
1da177e4 LT |
275 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
276 | .generator = crypt_iv_plain_gen | |
277 | }; | |
278 | ||
279 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
280 | .ctr = crypt_iv_essiv_ctr, | |
281 | .dtr = crypt_iv_essiv_dtr, | |
282 | .generator = crypt_iv_essiv_gen | |
283 | }; | |
284 | ||
48527fa7 RS |
285 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
286 | .ctr = crypt_iv_benbi_ctr, | |
287 | .dtr = crypt_iv_benbi_dtr, | |
288 | .generator = crypt_iv_benbi_gen | |
289 | }; | |
1da177e4 | 290 | |
46b47730 LN |
291 | static struct crypt_iv_operations crypt_iv_null_ops = { |
292 | .generator = crypt_iv_null_gen | |
293 | }; | |
294 | ||
858119e1 | 295 | static int |
1da177e4 LT |
296 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
297 | struct scatterlist *in, unsigned int length, | |
298 | int write, sector_t sector) | |
299 | { | |
45789328 | 300 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
d1806f6a HX |
301 | struct blkcipher_desc desc = { |
302 | .tfm = cc->tfm, | |
303 | .info = iv, | |
304 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, | |
305 | }; | |
1da177e4 LT |
306 | int r; |
307 | ||
308 | if (cc->iv_gen_ops) { | |
309 | r = cc->iv_gen_ops->generator(cc, iv, sector); | |
310 | if (r < 0) | |
311 | return r; | |
312 | ||
313 | if (write) | |
d1806f6a | 314 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
1da177e4 | 315 | else |
d1806f6a | 316 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
1da177e4 LT |
317 | } else { |
318 | if (write) | |
d1806f6a | 319 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
1da177e4 | 320 | else |
d1806f6a | 321 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
1da177e4 LT |
322 | } |
323 | ||
324 | return r; | |
325 | } | |
326 | ||
d469f841 MB |
327 | static void crypt_convert_init(struct crypt_config *cc, |
328 | struct convert_context *ctx, | |
329 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 330 | sector_t sector) |
1da177e4 LT |
331 | { |
332 | ctx->bio_in = bio_in; | |
333 | ctx->bio_out = bio_out; | |
334 | ctx->offset_in = 0; | |
335 | ctx->offset_out = 0; | |
336 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
337 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
338 | ctx->sector = sector + cc->iv_offset; | |
1da177e4 LT |
339 | } |
340 | ||
341 | /* | |
342 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
343 | */ | |
344 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 345 | struct convert_context *ctx) |
1da177e4 LT |
346 | { |
347 | int r = 0; | |
348 | ||
349 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
350 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
351 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
352 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
45711f1a JA |
353 | struct scatterlist sg_in, sg_out; |
354 | ||
355 | sg_init_table(&sg_in, 1); | |
642f1490 | 356 | sg_set_page(&sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, bv_in->bv_offset + ctx->offset_in); |
45711f1a JA |
357 | |
358 | sg_init_table(&sg_out, 1); | |
642f1490 | 359 | sg_set_page(&sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, bv_out->bv_offset + ctx->offset_out); |
1da177e4 LT |
360 | |
361 | ctx->offset_in += sg_in.length; | |
362 | if (ctx->offset_in >= bv_in->bv_len) { | |
363 | ctx->offset_in = 0; | |
364 | ctx->idx_in++; | |
365 | } | |
366 | ||
367 | ctx->offset_out += sg_out.length; | |
368 | if (ctx->offset_out >= bv_out->bv_len) { | |
369 | ctx->offset_out = 0; | |
370 | ctx->idx_out++; | |
371 | } | |
372 | ||
373 | r = crypt_convert_scatterlist(cc, &sg_out, &sg_in, sg_in.length, | |
fcd369da | 374 | bio_data_dir(ctx->bio_in) == WRITE, ctx->sector); |
1da177e4 LT |
375 | if (r < 0) |
376 | break; | |
377 | ||
378 | ctx->sector++; | |
379 | } | |
380 | ||
381 | return r; | |
382 | } | |
383 | ||
d469f841 MB |
384 | static void dm_crypt_bio_destructor(struct bio *bio) |
385 | { | |
028867ac | 386 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
387 | struct crypt_config *cc = io->target->private; |
388 | ||
389 | bio_free(bio, cc->bs); | |
d469f841 | 390 | } |
6a24c718 | 391 | |
1da177e4 LT |
392 | /* |
393 | * Generate a new unfragmented bio with the given size | |
394 | * This should never violate the device limitations | |
395 | * May return a smaller bio when running out of pages | |
396 | */ | |
028867ac | 397 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 398 | { |
027581f3 | 399 | struct crypt_config *cc = io->target->private; |
8b004457 | 400 | struct bio *clone; |
1da177e4 | 401 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 402 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
403 | unsigned i, len; |
404 | struct page *page; | |
1da177e4 | 405 | |
2f9941b6 | 406 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 407 | if (!clone) |
1da177e4 | 408 | return NULL; |
1da177e4 | 409 | |
027581f3 | 410 | clone_init(io, clone); |
6a24c718 | 411 | |
f97380bc | 412 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
413 | page = mempool_alloc(cc->page_pool, gfp_mask); |
414 | if (!page) | |
1da177e4 LT |
415 | break; |
416 | ||
417 | /* | |
418 | * if additional pages cannot be allocated without waiting, | |
419 | * return a partially allocated bio, the caller will then try | |
420 | * to allocate additional bios while submitting this partial bio | |
421 | */ | |
f97380bc | 422 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
423 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
424 | ||
91e10625 MB |
425 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
426 | ||
427 | if (!bio_add_page(clone, page, len, 0)) { | |
428 | mempool_free(page, cc->page_pool); | |
429 | break; | |
430 | } | |
1da177e4 | 431 | |
91e10625 | 432 | size -= len; |
1da177e4 LT |
433 | } |
434 | ||
8b004457 MB |
435 | if (!clone->bi_size) { |
436 | bio_put(clone); | |
1da177e4 LT |
437 | return NULL; |
438 | } | |
439 | ||
8b004457 | 440 | return clone; |
1da177e4 LT |
441 | } |
442 | ||
644bd2f0 | 443 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 444 | { |
644bd2f0 | 445 | unsigned int i; |
1da177e4 LT |
446 | struct bio_vec *bv; |
447 | ||
644bd2f0 | 448 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 449 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
450 | BUG_ON(!bv->bv_page); |
451 | mempool_free(bv->bv_page, cc->page_pool); | |
452 | bv->bv_page = NULL; | |
453 | } | |
454 | } | |
455 | ||
456 | /* | |
457 | * One of the bios was finished. Check for completion of | |
458 | * the whole request and correctly clean up the buffer. | |
459 | */ | |
5742fd77 | 460 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 461 | { |
5742fd77 | 462 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
463 | |
464 | if (!atomic_dec_and_test(&io->pending)) | |
465 | return; | |
466 | ||
6712ecf8 | 467 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
468 | mempool_free(io, cc->io_pool); |
469 | } | |
470 | ||
471 | /* | |
cabf08e4 | 472 | * kcryptd/kcryptd_io: |
1da177e4 LT |
473 | * |
474 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 475 | * interrupt context. |
cabf08e4 MB |
476 | * |
477 | * kcryptd performs the actual encryption or decryption. | |
478 | * | |
479 | * kcryptd_io performs the IO submission. | |
480 | * | |
481 | * They must be separated as otherwise the final stages could be | |
482 | * starved by new requests which can block in the first stages due | |
483 | * to memory allocation. | |
1da177e4 | 484 | */ |
6712ecf8 | 485 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 486 | { |
028867ac | 487 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 488 | struct crypt_config *cc = io->target->private; |
ee7a491e | 489 | unsigned rw = bio_data_dir(clone); |
8b004457 | 490 | |
adfe4770 MB |
491 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
492 | error = -EIO; | |
493 | ||
8b004457 | 494 | /* |
6712ecf8 | 495 | * free the processed pages |
8b004457 | 496 | */ |
ee7a491e | 497 | if (rw == WRITE) |
644bd2f0 | 498 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
499 | |
500 | bio_put(clone); | |
8b004457 | 501 | |
ee7a491e MB |
502 | if (rw == READ && !error) { |
503 | kcryptd_queue_crypt(io); | |
504 | return; | |
505 | } | |
5742fd77 MB |
506 | |
507 | if (unlikely(error)) | |
508 | io->error = error; | |
509 | ||
510 | crypt_dec_pending(io); | |
8b004457 MB |
511 | } |
512 | ||
028867ac | 513 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
514 | { |
515 | struct crypt_config *cc = io->target->private; | |
516 | ||
517 | clone->bi_private = io; | |
518 | clone->bi_end_io = crypt_endio; | |
519 | clone->bi_bdev = cc->dev->bdev; | |
520 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 521 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
522 | } |
523 | ||
4e4eef64 | 524 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
525 | { |
526 | struct crypt_config *cc = io->target->private; | |
527 | struct bio *base_bio = io->base_bio; | |
528 | struct bio *clone; | |
93e605c2 MB |
529 | sector_t sector = base_bio->bi_sector - io->target->begin; |
530 | ||
531 | atomic_inc(&io->pending); | |
8b004457 MB |
532 | |
533 | /* | |
534 | * The block layer might modify the bvec array, so always | |
535 | * copy the required bvecs because we need the original | |
536 | * one in order to decrypt the whole bio data *afterwards*. | |
537 | */ | |
6a24c718 | 538 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 539 | if (unlikely(!clone)) { |
5742fd77 MB |
540 | io->error = -ENOMEM; |
541 | crypt_dec_pending(io); | |
23541d2d | 542 | return; |
93e605c2 | 543 | } |
8b004457 MB |
544 | |
545 | clone_init(io, clone); | |
546 | clone->bi_idx = 0; | |
547 | clone->bi_vcnt = bio_segments(base_bio); | |
548 | clone->bi_size = base_bio->bi_size; | |
93e605c2 | 549 | clone->bi_sector = cc->start + sector; |
8b004457 MB |
550 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
551 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 552 | |
93e605c2 | 553 | generic_make_request(clone); |
8b004457 MB |
554 | } |
555 | ||
4e4eef64 MB |
556 | static void kcryptd_io_write(struct dm_crypt_io *io) |
557 | { | |
558 | } | |
559 | ||
395b167c AK |
560 | static void kcryptd_io(struct work_struct *work) |
561 | { | |
562 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
563 | ||
564 | if (bio_data_dir(io->base_bio) == READ) | |
565 | kcryptd_io_read(io); | |
566 | else | |
567 | kcryptd_io_write(io); | |
568 | } | |
569 | ||
570 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
571 | { | |
572 | struct crypt_config *cc = io->target->private; | |
573 | ||
574 | INIT_WORK(&io->work, kcryptd_io); | |
575 | queue_work(cc->io_queue, &io->work); | |
576 | } | |
577 | ||
4e4eef64 MB |
578 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error) |
579 | { | |
580 | } | |
581 | ||
582 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) | |
8b004457 MB |
583 | { |
584 | struct crypt_config *cc = io->target->private; | |
585 | struct bio *base_bio = io->base_bio; | |
586 | struct bio *clone; | |
93e605c2 MB |
587 | unsigned remaining = base_bio->bi_size; |
588 | sector_t sector = base_bio->bi_sector - io->target->begin; | |
8b004457 | 589 | |
93e605c2 | 590 | atomic_inc(&io->pending); |
8b004457 | 591 | |
fcd369da | 592 | crypt_convert_init(cc, &io->ctx, NULL, base_bio, sector); |
8b004457 | 593 | |
93e605c2 MB |
594 | /* |
595 | * The allocated buffers can be smaller than the whole bio, | |
596 | * so repeat the whole process until all the data can be handled. | |
597 | */ | |
598 | while (remaining) { | |
f97380bc | 599 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 600 | if (unlikely(!clone)) { |
5742fd77 MB |
601 | io->error = -ENOMEM; |
602 | crypt_dec_pending(io); | |
23541d2d MB |
603 | return; |
604 | } | |
93e605c2 | 605 | |
53017030 MB |
606 | io->ctx.bio_out = clone; |
607 | io->ctx.idx_out = 0; | |
93e605c2 | 608 | |
53017030 | 609 | if (unlikely(crypt_convert(cc, &io->ctx) < 0)) { |
644bd2f0 | 610 | crypt_free_buffer_pages(cc, clone); |
93e605c2 | 611 | bio_put(clone); |
5742fd77 MB |
612 | io->error = -EIO; |
613 | crypt_dec_pending(io); | |
23541d2d | 614 | return; |
93e605c2 MB |
615 | } |
616 | ||
f97380bc | 617 | /* crypt_convert should have filled the clone bio */ |
53017030 | 618 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); |
f97380bc | 619 | |
93e605c2 | 620 | clone->bi_sector = cc->start + sector; |
93e605c2 MB |
621 | remaining -= clone->bi_size; |
622 | sector += bio_sectors(clone); | |
623 | ||
2f9941b6 OK |
624 | /* Grab another reference to the io struct |
625 | * before we kick off the request */ | |
23541d2d MB |
626 | if (remaining) |
627 | atomic_inc(&io->pending); | |
628 | ||
93e605c2 MB |
629 | generic_make_request(clone); |
630 | ||
98221eb7 OK |
631 | /* Do not reference clone after this - it |
632 | * may be gone already. */ | |
633 | ||
93e605c2 MB |
634 | /* out of memory -> run queues */ |
635 | if (remaining) | |
98221eb7 | 636 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 637 | } |
8b004457 MB |
638 | } |
639 | ||
4e4eef64 | 640 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
641 | { |
642 | if (unlikely(error < 0)) | |
643 | io->error = -EIO; | |
644 | ||
645 | crypt_dec_pending(io); | |
646 | } | |
647 | ||
4e4eef64 | 648 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
649 | { |
650 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 651 | int r = 0; |
1da177e4 | 652 | |
53017030 | 653 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
fcd369da | 654 | io->base_bio->bi_sector - io->target->begin); |
1da177e4 | 655 | |
5742fd77 MB |
656 | r = crypt_convert(cc, &io->ctx); |
657 | ||
4e4eef64 | 658 | kcryptd_crypt_read_done(io, r); |
1da177e4 LT |
659 | } |
660 | ||
395b167c | 661 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 662 | { |
028867ac | 663 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 664 | |
cabf08e4 | 665 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 666 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 667 | else |
395b167c | 668 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
669 | } |
670 | ||
395b167c | 671 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 672 | { |
395b167c | 673 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 674 | |
395b167c AK |
675 | INIT_WORK(&io->work, kcryptd_crypt); |
676 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
677 | } |
678 | ||
679 | /* | |
680 | * Decode key from its hex representation | |
681 | */ | |
682 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
683 | { | |
684 | char buffer[3]; | |
685 | char *endp; | |
686 | unsigned int i; | |
687 | ||
688 | buffer[2] = '\0'; | |
689 | ||
8b004457 | 690 | for (i = 0; i < size; i++) { |
1da177e4 LT |
691 | buffer[0] = *hex++; |
692 | buffer[1] = *hex++; | |
693 | ||
694 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
695 | ||
696 | if (endp != &buffer[2]) | |
697 | return -EINVAL; | |
698 | } | |
699 | ||
700 | if (*hex != '\0') | |
701 | return -EINVAL; | |
702 | ||
703 | return 0; | |
704 | } | |
705 | ||
706 | /* | |
707 | * Encode key into its hex representation | |
708 | */ | |
709 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
710 | { | |
711 | unsigned int i; | |
712 | ||
8b004457 | 713 | for (i = 0; i < size; i++) { |
1da177e4 LT |
714 | sprintf(hex, "%02x", *key); |
715 | hex += 2; | |
716 | key++; | |
717 | } | |
718 | } | |
719 | ||
e48d4bbf MB |
720 | static int crypt_set_key(struct crypt_config *cc, char *key) |
721 | { | |
722 | unsigned key_size = strlen(key) >> 1; | |
723 | ||
724 | if (cc->key_size && cc->key_size != key_size) | |
725 | return -EINVAL; | |
726 | ||
727 | cc->key_size = key_size; /* initial settings */ | |
728 | ||
729 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 730 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
731 | return -EINVAL; |
732 | ||
733 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
734 | ||
735 | return 0; | |
736 | } | |
737 | ||
738 | static int crypt_wipe_key(struct crypt_config *cc) | |
739 | { | |
740 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
741 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
742 | return 0; | |
743 | } | |
744 | ||
1da177e4 LT |
745 | /* |
746 | * Construct an encryption mapping: | |
747 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
748 | */ | |
749 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
750 | { | |
751 | struct crypt_config *cc; | |
d1806f6a | 752 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
753 | char *tmp; |
754 | char *cipher; | |
755 | char *chainmode; | |
756 | char *ivmode; | |
757 | char *ivopts; | |
1da177e4 | 758 | unsigned int key_size; |
4ee218cd | 759 | unsigned long long tmpll; |
1da177e4 LT |
760 | |
761 | if (argc != 5) { | |
72d94861 | 762 | ti->error = "Not enough arguments"; |
1da177e4 LT |
763 | return -EINVAL; |
764 | } | |
765 | ||
766 | tmp = argv[0]; | |
767 | cipher = strsep(&tmp, "-"); | |
768 | chainmode = strsep(&tmp, "-"); | |
769 | ivopts = strsep(&tmp, "-"); | |
770 | ivmode = strsep(&ivopts, ":"); | |
771 | ||
772 | if (tmp) | |
72d94861 | 773 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
774 | |
775 | key_size = strlen(argv[1]) >> 1; | |
776 | ||
e48d4bbf | 777 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
778 | if (cc == NULL) { |
779 | ti->error = | |
72d94861 | 780 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
781 | return -ENOMEM; |
782 | } | |
783 | ||
e48d4bbf | 784 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 785 | ti->error = "Error decoding key"; |
636d5786 | 786 | goto bad_cipher; |
1da177e4 LT |
787 | } |
788 | ||
789 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
790 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
791 | chainmode = "cbc"; | |
792 | ivmode = "plain"; | |
793 | } | |
794 | ||
d1806f6a HX |
795 | if (strcmp(chainmode, "ecb") && !ivmode) { |
796 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 797 | goto bad_cipher; |
1da177e4 LT |
798 | } |
799 | ||
d469f841 MB |
800 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
801 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 802 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 803 | goto bad_cipher; |
1da177e4 LT |
804 | } |
805 | ||
d1806f6a HX |
806 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
807 | if (IS_ERR(tfm)) { | |
72d94861 | 808 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 809 | goto bad_cipher; |
1da177e4 | 810 | } |
1da177e4 | 811 | |
d1806f6a HX |
812 | strcpy(cc->cipher, cipher); |
813 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
814 | cc->tfm = tfm; |
815 | ||
816 | /* | |
48527fa7 | 817 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
818 | * See comments at iv code |
819 | */ | |
820 | ||
821 | if (ivmode == NULL) | |
822 | cc->iv_gen_ops = NULL; | |
823 | else if (strcmp(ivmode, "plain") == 0) | |
824 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
825 | else if (strcmp(ivmode, "essiv") == 0) | |
826 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
827 | else if (strcmp(ivmode, "benbi") == 0) |
828 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
829 | else if (strcmp(ivmode, "null") == 0) |
830 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 831 | else { |
72d94861 | 832 | ti->error = "Invalid IV mode"; |
636d5786 | 833 | goto bad_ivmode; |
1da177e4 LT |
834 | } |
835 | ||
836 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
837 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 838 | goto bad_ivmode; |
1da177e4 | 839 | |
d1806f6a HX |
840 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
841 | if (cc->iv_size) | |
1da177e4 | 842 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 843 | cc->iv_size = max(cc->iv_size, |
d469f841 | 844 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 845 | else { |
1da177e4 | 846 | if (cc->iv_gen_ops) { |
72d94861 | 847 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
848 | if (cc->iv_gen_ops->dtr) |
849 | cc->iv_gen_ops->dtr(cc); | |
850 | cc->iv_gen_ops = NULL; | |
851 | } | |
852 | } | |
853 | ||
93d2341c | 854 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 855 | if (!cc->io_pool) { |
72d94861 | 856 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 857 | goto bad_slab_pool; |
1da177e4 LT |
858 | } |
859 | ||
a19b27ce | 860 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 861 | if (!cc->page_pool) { |
72d94861 | 862 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 863 | goto bad_page_pool; |
1da177e4 LT |
864 | } |
865 | ||
5972511b | 866 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
867 | if (!cc->bs) { |
868 | ti->error = "Cannot allocate crypt bioset"; | |
869 | goto bad_bs; | |
870 | } | |
871 | ||
d1806f6a | 872 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 873 | ti->error = "Error setting key"; |
636d5786 | 874 | goto bad_device; |
1da177e4 LT |
875 | } |
876 | ||
4ee218cd | 877 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 878 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 879 | goto bad_device; |
1da177e4 | 880 | } |
4ee218cd | 881 | cc->iv_offset = tmpll; |
1da177e4 | 882 | |
4ee218cd | 883 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 884 | ti->error = "Invalid device sector"; |
636d5786 | 885 | goto bad_device; |
1da177e4 | 886 | } |
4ee218cd | 887 | cc->start = tmpll; |
1da177e4 LT |
888 | |
889 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 890 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 891 | ti->error = "Device lookup failed"; |
636d5786 | 892 | goto bad_device; |
1da177e4 LT |
893 | } |
894 | ||
895 | if (ivmode && cc->iv_gen_ops) { | |
896 | if (ivopts) | |
897 | *(ivopts - 1) = ':'; | |
898 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
899 | if (!cc->iv_mode) { | |
72d94861 | 900 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 901 | goto bad_ivmode_string; |
1da177e4 LT |
902 | } |
903 | strcpy(cc->iv_mode, ivmode); | |
904 | } else | |
905 | cc->iv_mode = NULL; | |
906 | ||
cabf08e4 MB |
907 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
908 | if (!cc->io_queue) { | |
909 | ti->error = "Couldn't create kcryptd io queue"; | |
910 | goto bad_io_queue; | |
911 | } | |
912 | ||
913 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
914 | if (!cc->crypt_queue) { | |
9934a8be | 915 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 916 | goto bad_crypt_queue; |
9934a8be MB |
917 | } |
918 | ||
1da177e4 LT |
919 | ti->private = cc; |
920 | return 0; | |
921 | ||
cabf08e4 MB |
922 | bad_crypt_queue: |
923 | destroy_workqueue(cc->io_queue); | |
924 | bad_io_queue: | |
9934a8be | 925 | kfree(cc->iv_mode); |
636d5786 | 926 | bad_ivmode_string: |
55b42c5a | 927 | dm_put_device(ti, cc->dev); |
636d5786 | 928 | bad_device: |
6a24c718 MB |
929 | bioset_free(cc->bs); |
930 | bad_bs: | |
1da177e4 | 931 | mempool_destroy(cc->page_pool); |
636d5786 | 932 | bad_page_pool: |
1da177e4 | 933 | mempool_destroy(cc->io_pool); |
636d5786 | 934 | bad_slab_pool: |
1da177e4 LT |
935 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
936 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 937 | bad_ivmode: |
d1806f6a | 938 | crypto_free_blkcipher(tfm); |
636d5786 | 939 | bad_cipher: |
9d3520a3 SR |
940 | /* Must zero key material before freeing */ |
941 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
942 | kfree(cc); |
943 | return -EINVAL; | |
944 | } | |
945 | ||
946 | static void crypt_dtr(struct dm_target *ti) | |
947 | { | |
948 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
949 | ||
cabf08e4 MB |
950 | destroy_workqueue(cc->io_queue); |
951 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 952 | |
6a24c718 | 953 | bioset_free(cc->bs); |
1da177e4 LT |
954 | mempool_destroy(cc->page_pool); |
955 | mempool_destroy(cc->io_pool); | |
956 | ||
990a8baf | 957 | kfree(cc->iv_mode); |
1da177e4 LT |
958 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
959 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 960 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 961 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
962 | |
963 | /* Must zero key material before freeing */ | |
964 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
965 | kfree(cc); |
966 | } | |
967 | ||
1da177e4 LT |
968 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
969 | union map_info *map_context) | |
970 | { | |
8b004457 | 971 | struct crypt_config *cc = ti->private; |
028867ac | 972 | struct dm_crypt_io *io; |
1da177e4 | 973 | |
e48d4bbf | 974 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 975 | io->target = ti; |
8b004457 | 976 | io->base_bio = bio; |
cabf08e4 | 977 | io->error = 0; |
93e605c2 | 978 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
979 | |
980 | if (bio_data_dir(io->base_bio) == READ) | |
981 | kcryptd_queue_io(io); | |
982 | else | |
983 | kcryptd_queue_crypt(io); | |
1da177e4 | 984 | |
d2a7ad29 | 985 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
986 | } |
987 | ||
988 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
989 | char *result, unsigned int maxlen) | |
990 | { | |
991 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
992 | unsigned int sz = 0; |
993 | ||
994 | switch (type) { | |
995 | case STATUSTYPE_INFO: | |
996 | result[0] = '\0'; | |
997 | break; | |
998 | ||
999 | case STATUSTYPE_TABLE: | |
1da177e4 | 1000 | if (cc->iv_mode) |
37af6560 CS |
1001 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1002 | cc->iv_mode); | |
1da177e4 | 1003 | else |
37af6560 | 1004 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1005 | |
1006 | if (cc->key_size > 0) { | |
1007 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1008 | return -ENOMEM; | |
1009 | ||
1010 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1011 | sz += cc->key_size << 1; | |
1012 | } else { | |
1013 | if (sz >= maxlen) | |
1014 | return -ENOMEM; | |
1015 | result[sz++] = '-'; | |
1016 | } | |
1017 | ||
4ee218cd AM |
1018 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1019 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1020 | break; |
1021 | } | |
1022 | return 0; | |
1023 | } | |
1024 | ||
e48d4bbf MB |
1025 | static void crypt_postsuspend(struct dm_target *ti) |
1026 | { | |
1027 | struct crypt_config *cc = ti->private; | |
1028 | ||
1029 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1030 | } | |
1031 | ||
1032 | static int crypt_preresume(struct dm_target *ti) | |
1033 | { | |
1034 | struct crypt_config *cc = ti->private; | |
1035 | ||
1036 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1037 | DMERR("aborting resume - crypt key is not set."); | |
1038 | return -EAGAIN; | |
1039 | } | |
1040 | ||
1041 | return 0; | |
1042 | } | |
1043 | ||
1044 | static void crypt_resume(struct dm_target *ti) | |
1045 | { | |
1046 | struct crypt_config *cc = ti->private; | |
1047 | ||
1048 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1049 | } | |
1050 | ||
1051 | /* Message interface | |
1052 | * key set <key> | |
1053 | * key wipe | |
1054 | */ | |
1055 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1056 | { | |
1057 | struct crypt_config *cc = ti->private; | |
1058 | ||
1059 | if (argc < 2) | |
1060 | goto error; | |
1061 | ||
1062 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1063 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1064 | DMWARN("not suspended during key manipulation."); | |
1065 | return -EINVAL; | |
1066 | } | |
1067 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1068 | return crypt_set_key(cc, argv[2]); | |
1069 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1070 | return crypt_wipe_key(cc); | |
1071 | } | |
1072 | ||
1073 | error: | |
1074 | DMWARN("unrecognised message received."); | |
1075 | return -EINVAL; | |
1076 | } | |
1077 | ||
1da177e4 LT |
1078 | static struct target_type crypt_target = { |
1079 | .name = "crypt", | |
46b47730 | 1080 | .version= {1, 5, 0}, |
1da177e4 LT |
1081 | .module = THIS_MODULE, |
1082 | .ctr = crypt_ctr, | |
1083 | .dtr = crypt_dtr, | |
1084 | .map = crypt_map, | |
1085 | .status = crypt_status, | |
e48d4bbf MB |
1086 | .postsuspend = crypt_postsuspend, |
1087 | .preresume = crypt_preresume, | |
1088 | .resume = crypt_resume, | |
1089 | .message = crypt_message, | |
1da177e4 LT |
1090 | }; |
1091 | ||
1092 | static int __init dm_crypt_init(void) | |
1093 | { | |
1094 | int r; | |
1095 | ||
028867ac | 1096 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1097 | if (!_crypt_io_pool) |
1098 | return -ENOMEM; | |
1099 | ||
1da177e4 LT |
1100 | r = dm_register_target(&crypt_target); |
1101 | if (r < 0) { | |
72d94861 | 1102 | DMERR("register failed %d", r); |
9934a8be | 1103 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1104 | } |
1105 | ||
1da177e4 LT |
1106 | return r; |
1107 | } | |
1108 | ||
1109 | static void __exit dm_crypt_exit(void) | |
1110 | { | |
1111 | int r = dm_unregister_target(&crypt_target); | |
1112 | ||
1113 | if (r < 0) | |
72d94861 | 1114 | DMERR("unregister failed %d", r); |
1da177e4 | 1115 | |
1da177e4 LT |
1116 | kmem_cache_destroy(_crypt_io_pool); |
1117 | } | |
1118 | ||
1119 | module_init(dm_crypt_init); | |
1120 | module_exit(dm_crypt_exit); | |
1121 | ||
1122 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1123 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1124 | MODULE_LICENSE("GPL"); |