Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
4e4eef64 | 4 | * Copyright (C) 2006-2007 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
5 | * |
6 | * This file is released under the GPL. | |
7 | */ | |
8 | ||
d1806f6a | 9 | #include <linux/err.h> |
1da177e4 LT |
10 | #include <linux/module.h> |
11 | #include <linux/init.h> | |
12 | #include <linux/kernel.h> | |
13 | #include <linux/bio.h> | |
14 | #include <linux/blkdev.h> | |
15 | #include <linux/mempool.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/crypto.h> | |
18 | #include <linux/workqueue.h> | |
3fcfab16 | 19 | #include <linux/backing-dev.h> |
1da177e4 | 20 | #include <asm/atomic.h> |
378f058c | 21 | #include <linux/scatterlist.h> |
1da177e4 | 22 | #include <asm/page.h> |
48527fa7 | 23 | #include <asm/unaligned.h> |
1da177e4 LT |
24 | |
25 | #include "dm.h" | |
26 | ||
72d94861 | 27 | #define DM_MSG_PREFIX "crypt" |
e48d4bbf | 28 | #define MESG_STR(x) x, sizeof(x) |
1da177e4 | 29 | |
1da177e4 LT |
30 | /* |
31 | * context holding the current state of a multi-part conversion | |
32 | */ | |
33 | struct convert_context { | |
34 | struct bio *bio_in; | |
35 | struct bio *bio_out; | |
36 | unsigned int offset_in; | |
37 | unsigned int offset_out; | |
38 | unsigned int idx_in; | |
39 | unsigned int idx_out; | |
40 | sector_t sector; | |
1da177e4 LT |
41 | }; |
42 | ||
53017030 MB |
43 | /* |
44 | * per bio private data | |
45 | */ | |
46 | struct dm_crypt_io { | |
47 | struct dm_target *target; | |
48 | struct bio *base_bio; | |
49 | struct work_struct work; | |
50 | ||
51 | struct convert_context ctx; | |
52 | ||
53 | atomic_t pending; | |
54 | int error; | |
0c395b0f | 55 | sector_t sector; |
53017030 MB |
56 | }; |
57 | ||
01482b76 MB |
58 | struct dm_crypt_request { |
59 | struct scatterlist sg_in; | |
60 | struct scatterlist sg_out; | |
61 | }; | |
62 | ||
1da177e4 LT |
63 | struct crypt_config; |
64 | ||
65 | struct crypt_iv_operations { | |
66 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 67 | const char *opts); |
1da177e4 LT |
68 | void (*dtr)(struct crypt_config *cc); |
69 | const char *(*status)(struct crypt_config *cc); | |
70 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
71 | }; | |
72 | ||
73 | /* | |
74 | * Crypt: maps a linear range of a block device | |
75 | * and encrypts / decrypts at the same time. | |
76 | */ | |
e48d4bbf | 77 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
78 | struct crypt_config { |
79 | struct dm_dev *dev; | |
80 | sector_t start; | |
81 | ||
82 | /* | |
83 | * pool for per bio private data and | |
84 | * for encryption buffer pages | |
85 | */ | |
86 | mempool_t *io_pool; | |
87 | mempool_t *page_pool; | |
6a24c718 | 88 | struct bio_set *bs; |
1da177e4 | 89 | |
cabf08e4 MB |
90 | struct workqueue_struct *io_queue; |
91 | struct workqueue_struct *crypt_queue; | |
1da177e4 LT |
92 | /* |
93 | * crypto related data | |
94 | */ | |
95 | struct crypt_iv_operations *iv_gen_ops; | |
96 | char *iv_mode; | |
79066ad3 HX |
97 | union { |
98 | struct crypto_cipher *essiv_tfm; | |
99 | int benbi_shift; | |
100 | } iv_gen_private; | |
1da177e4 LT |
101 | sector_t iv_offset; |
102 | unsigned int iv_size; | |
103 | ||
d1806f6a HX |
104 | char cipher[CRYPTO_MAX_ALG_NAME]; |
105 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
106 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 107 | unsigned long flags; |
1da177e4 LT |
108 | unsigned int key_size; |
109 | u8 key[0]; | |
110 | }; | |
111 | ||
6a24c718 | 112 | #define MIN_IOS 16 |
1da177e4 LT |
113 | #define MIN_POOL_PAGES 32 |
114 | #define MIN_BIO_PAGES 8 | |
115 | ||
e18b890b | 116 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 117 | |
028867ac | 118 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 119 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 120 | |
1da177e4 LT |
121 | /* |
122 | * Different IV generation algorithms: | |
123 | * | |
3c164bd8 | 124 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 125 | * number, padded with zeros if necessary. |
1da177e4 | 126 | * |
3c164bd8 RS |
127 | * essiv: "encrypted sector|salt initial vector", the sector number is |
128 | * encrypted with the bulk cipher using a salt as key. The salt | |
129 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 130 | * |
48527fa7 RS |
131 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
132 | * (needed for LRW-32-AES and possible other narrow block modes) | |
133 | * | |
46b47730 LN |
134 | * null: the initial vector is always zero. Provides compatibility with |
135 | * obsolete loop_fish2 devices. Do not use for new devices. | |
136 | * | |
1da177e4 LT |
137 | * plumb: unimplemented, see: |
138 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
139 | */ | |
140 | ||
141 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
142 | { | |
143 | memset(iv, 0, cc->iv_size); | |
144 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
145 | ||
146 | return 0; | |
147 | } | |
148 | ||
149 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 150 | const char *opts) |
1da177e4 | 151 | { |
d1806f6a | 152 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
153 | struct crypto_hash *hash_tfm; |
154 | struct hash_desc desc; | |
1da177e4 LT |
155 | struct scatterlist sg; |
156 | unsigned int saltsize; | |
157 | u8 *salt; | |
d1806f6a | 158 | int err; |
1da177e4 LT |
159 | |
160 | if (opts == NULL) { | |
72d94861 | 161 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
162 | return -EINVAL; |
163 | } | |
164 | ||
165 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
166 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
167 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 168 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 169 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
170 | } |
171 | ||
35058687 | 172 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
173 | salt = kmalloc(saltsize, GFP_KERNEL); |
174 | if (salt == NULL) { | |
72d94861 | 175 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 176 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
177 | return -ENOMEM; |
178 | } | |
179 | ||
68e3f5dd | 180 | sg_init_one(&sg, cc->key, cc->key_size); |
35058687 HX |
181 | desc.tfm = hash_tfm; |
182 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
183 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
184 | crypto_free_hash(hash_tfm); | |
185 | ||
186 | if (err) { | |
187 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 188 | kfree(salt); |
35058687 HX |
189 | return err; |
190 | } | |
1da177e4 LT |
191 | |
192 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
193 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
194 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 195 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 196 | kfree(salt); |
d1806f6a | 197 | return PTR_ERR(essiv_tfm); |
1da177e4 | 198 | } |
d1806f6a HX |
199 | if (crypto_cipher_blocksize(essiv_tfm) != |
200 | crypto_blkcipher_ivsize(cc->tfm)) { | |
72d94861 | 201 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 202 | "not match IV size of block cipher"; |
d1806f6a | 203 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
204 | kfree(salt); |
205 | return -EINVAL; | |
206 | } | |
d1806f6a HX |
207 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
208 | if (err) { | |
72d94861 | 209 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 210 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 211 | kfree(salt); |
d1806f6a | 212 | return err; |
1da177e4 LT |
213 | } |
214 | kfree(salt); | |
215 | ||
79066ad3 | 216 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
217 | return 0; |
218 | } | |
219 | ||
220 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
221 | { | |
79066ad3 HX |
222 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
223 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
224 | } |
225 | ||
226 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
227 | { | |
1da177e4 LT |
228 | memset(iv, 0, cc->iv_size); |
229 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 230 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
231 | return 0; |
232 | } | |
233 | ||
48527fa7 RS |
234 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
235 | const char *opts) | |
236 | { | |
237 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); | |
f0d1b0b3 | 238 | int log = ilog2(bs); |
48527fa7 RS |
239 | |
240 | /* we need to calculate how far we must shift the sector count | |
241 | * to get the cipher block count, we use this shift in _gen */ | |
242 | ||
243 | if (1 << log != bs) { | |
244 | ti->error = "cypher blocksize is not a power of 2"; | |
245 | return -EINVAL; | |
246 | } | |
247 | ||
248 | if (log > 9) { | |
249 | ti->error = "cypher blocksize is > 512"; | |
250 | return -EINVAL; | |
251 | } | |
252 | ||
79066ad3 | 253 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
254 | |
255 | return 0; | |
256 | } | |
257 | ||
258 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
259 | { | |
48527fa7 RS |
260 | } |
261 | ||
262 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
263 | { | |
79066ad3 HX |
264 | __be64 val; |
265 | ||
48527fa7 | 266 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
267 | |
268 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
269 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 270 | |
1da177e4 LT |
271 | return 0; |
272 | } | |
273 | ||
46b47730 LN |
274 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
275 | { | |
276 | memset(iv, 0, cc->iv_size); | |
277 | ||
278 | return 0; | |
279 | } | |
280 | ||
1da177e4 LT |
281 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
282 | .generator = crypt_iv_plain_gen | |
283 | }; | |
284 | ||
285 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
286 | .ctr = crypt_iv_essiv_ctr, | |
287 | .dtr = crypt_iv_essiv_dtr, | |
288 | .generator = crypt_iv_essiv_gen | |
289 | }; | |
290 | ||
48527fa7 RS |
291 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
292 | .ctr = crypt_iv_benbi_ctr, | |
293 | .dtr = crypt_iv_benbi_dtr, | |
294 | .generator = crypt_iv_benbi_gen | |
295 | }; | |
1da177e4 | 296 | |
46b47730 LN |
297 | static struct crypt_iv_operations crypt_iv_null_ops = { |
298 | .generator = crypt_iv_null_gen | |
299 | }; | |
300 | ||
858119e1 | 301 | static int |
1da177e4 LT |
302 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
303 | struct scatterlist *in, unsigned int length, | |
304 | int write, sector_t sector) | |
305 | { | |
45789328 | 306 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
d1806f6a HX |
307 | struct blkcipher_desc desc = { |
308 | .tfm = cc->tfm, | |
309 | .info = iv, | |
310 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, | |
311 | }; | |
1da177e4 LT |
312 | int r; |
313 | ||
314 | if (cc->iv_gen_ops) { | |
315 | r = cc->iv_gen_ops->generator(cc, iv, sector); | |
316 | if (r < 0) | |
317 | return r; | |
318 | ||
319 | if (write) | |
d1806f6a | 320 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
1da177e4 | 321 | else |
d1806f6a | 322 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
1da177e4 LT |
323 | } else { |
324 | if (write) | |
d1806f6a | 325 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
1da177e4 | 326 | else |
d1806f6a | 327 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
1da177e4 LT |
328 | } |
329 | ||
330 | return r; | |
331 | } | |
332 | ||
d469f841 MB |
333 | static void crypt_convert_init(struct crypt_config *cc, |
334 | struct convert_context *ctx, | |
335 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 336 | sector_t sector) |
1da177e4 LT |
337 | { |
338 | ctx->bio_in = bio_in; | |
339 | ctx->bio_out = bio_out; | |
340 | ctx->offset_in = 0; | |
341 | ctx->offset_out = 0; | |
342 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
343 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
344 | ctx->sector = sector + cc->iv_offset; | |
1da177e4 LT |
345 | } |
346 | ||
01482b76 MB |
347 | static int crypt_convert_block(struct crypt_config *cc, |
348 | struct convert_context *ctx) | |
349 | { | |
350 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
351 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
352 | struct dm_crypt_request dmreq; | |
353 | ||
354 | sg_init_table(&dmreq.sg_in, 1); | |
355 | sg_set_page(&dmreq.sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
356 | bv_in->bv_offset + ctx->offset_in); | |
357 | ||
358 | sg_init_table(&dmreq.sg_out, 1); | |
359 | sg_set_page(&dmreq.sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
360 | bv_out->bv_offset + ctx->offset_out); | |
361 | ||
362 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
363 | if (ctx->offset_in >= bv_in->bv_len) { | |
364 | ctx->offset_in = 0; | |
365 | ctx->idx_in++; | |
366 | } | |
367 | ||
368 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
369 | if (ctx->offset_out >= bv_out->bv_len) { | |
370 | ctx->offset_out = 0; | |
371 | ctx->idx_out++; | |
372 | } | |
373 | ||
374 | return crypt_convert_scatterlist(cc, &dmreq.sg_out, &dmreq.sg_in, | |
375 | dmreq.sg_in.length, | |
376 | bio_data_dir(ctx->bio_in) == WRITE, | |
377 | ctx->sector); | |
378 | } | |
379 | ||
1da177e4 LT |
380 | /* |
381 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
382 | */ | |
383 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 384 | struct convert_context *ctx) |
1da177e4 LT |
385 | { |
386 | int r = 0; | |
387 | ||
388 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
389 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
01482b76 | 390 | r = crypt_convert_block(cc, ctx); |
1da177e4 LT |
391 | if (r < 0) |
392 | break; | |
393 | ||
394 | ctx->sector++; | |
395 | } | |
396 | ||
397 | return r; | |
398 | } | |
399 | ||
d469f841 MB |
400 | static void dm_crypt_bio_destructor(struct bio *bio) |
401 | { | |
028867ac | 402 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
403 | struct crypt_config *cc = io->target->private; |
404 | ||
405 | bio_free(bio, cc->bs); | |
d469f841 | 406 | } |
6a24c718 | 407 | |
1da177e4 LT |
408 | /* |
409 | * Generate a new unfragmented bio with the given size | |
410 | * This should never violate the device limitations | |
411 | * May return a smaller bio when running out of pages | |
412 | */ | |
028867ac | 413 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 414 | { |
027581f3 | 415 | struct crypt_config *cc = io->target->private; |
8b004457 | 416 | struct bio *clone; |
1da177e4 | 417 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 418 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
419 | unsigned i, len; |
420 | struct page *page; | |
1da177e4 | 421 | |
2f9941b6 | 422 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 423 | if (!clone) |
1da177e4 | 424 | return NULL; |
1da177e4 | 425 | |
027581f3 | 426 | clone_init(io, clone); |
6a24c718 | 427 | |
f97380bc | 428 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
429 | page = mempool_alloc(cc->page_pool, gfp_mask); |
430 | if (!page) | |
1da177e4 LT |
431 | break; |
432 | ||
433 | /* | |
434 | * if additional pages cannot be allocated without waiting, | |
435 | * return a partially allocated bio, the caller will then try | |
436 | * to allocate additional bios while submitting this partial bio | |
437 | */ | |
f97380bc | 438 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
439 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
440 | ||
91e10625 MB |
441 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
442 | ||
443 | if (!bio_add_page(clone, page, len, 0)) { | |
444 | mempool_free(page, cc->page_pool); | |
445 | break; | |
446 | } | |
1da177e4 | 447 | |
91e10625 | 448 | size -= len; |
1da177e4 LT |
449 | } |
450 | ||
8b004457 MB |
451 | if (!clone->bi_size) { |
452 | bio_put(clone); | |
1da177e4 LT |
453 | return NULL; |
454 | } | |
455 | ||
8b004457 | 456 | return clone; |
1da177e4 LT |
457 | } |
458 | ||
644bd2f0 | 459 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 460 | { |
644bd2f0 | 461 | unsigned int i; |
1da177e4 LT |
462 | struct bio_vec *bv; |
463 | ||
644bd2f0 | 464 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 465 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
466 | BUG_ON(!bv->bv_page); |
467 | mempool_free(bv->bv_page, cc->page_pool); | |
468 | bv->bv_page = NULL; | |
469 | } | |
470 | } | |
471 | ||
472 | /* | |
473 | * One of the bios was finished. Check for completion of | |
474 | * the whole request and correctly clean up the buffer. | |
475 | */ | |
5742fd77 | 476 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 477 | { |
5742fd77 | 478 | struct crypt_config *cc = io->target->private; |
1da177e4 LT |
479 | |
480 | if (!atomic_dec_and_test(&io->pending)) | |
481 | return; | |
482 | ||
6712ecf8 | 483 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
484 | mempool_free(io, cc->io_pool); |
485 | } | |
486 | ||
487 | /* | |
cabf08e4 | 488 | * kcryptd/kcryptd_io: |
1da177e4 LT |
489 | * |
490 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 491 | * interrupt context. |
cabf08e4 MB |
492 | * |
493 | * kcryptd performs the actual encryption or decryption. | |
494 | * | |
495 | * kcryptd_io performs the IO submission. | |
496 | * | |
497 | * They must be separated as otherwise the final stages could be | |
498 | * starved by new requests which can block in the first stages due | |
499 | * to memory allocation. | |
1da177e4 | 500 | */ |
6712ecf8 | 501 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 502 | { |
028867ac | 503 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 504 | struct crypt_config *cc = io->target->private; |
ee7a491e | 505 | unsigned rw = bio_data_dir(clone); |
8b004457 | 506 | |
adfe4770 MB |
507 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
508 | error = -EIO; | |
509 | ||
8b004457 | 510 | /* |
6712ecf8 | 511 | * free the processed pages |
8b004457 | 512 | */ |
ee7a491e | 513 | if (rw == WRITE) |
644bd2f0 | 514 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
515 | |
516 | bio_put(clone); | |
8b004457 | 517 | |
ee7a491e MB |
518 | if (rw == READ && !error) { |
519 | kcryptd_queue_crypt(io); | |
520 | return; | |
521 | } | |
5742fd77 MB |
522 | |
523 | if (unlikely(error)) | |
524 | io->error = error; | |
525 | ||
526 | crypt_dec_pending(io); | |
8b004457 MB |
527 | } |
528 | ||
028867ac | 529 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
530 | { |
531 | struct crypt_config *cc = io->target->private; | |
532 | ||
533 | clone->bi_private = io; | |
534 | clone->bi_end_io = crypt_endio; | |
535 | clone->bi_bdev = cc->dev->bdev; | |
536 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 537 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
538 | } |
539 | ||
4e4eef64 | 540 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
541 | { |
542 | struct crypt_config *cc = io->target->private; | |
543 | struct bio *base_bio = io->base_bio; | |
544 | struct bio *clone; | |
93e605c2 MB |
545 | |
546 | atomic_inc(&io->pending); | |
8b004457 MB |
547 | |
548 | /* | |
549 | * The block layer might modify the bvec array, so always | |
550 | * copy the required bvecs because we need the original | |
551 | * one in order to decrypt the whole bio data *afterwards*. | |
552 | */ | |
6a24c718 | 553 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 554 | if (unlikely(!clone)) { |
5742fd77 MB |
555 | io->error = -ENOMEM; |
556 | crypt_dec_pending(io); | |
23541d2d | 557 | return; |
93e605c2 | 558 | } |
8b004457 MB |
559 | |
560 | clone_init(io, clone); | |
561 | clone->bi_idx = 0; | |
562 | clone->bi_vcnt = bio_segments(base_bio); | |
563 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 564 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
565 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
566 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 567 | |
93e605c2 | 568 | generic_make_request(clone); |
8b004457 MB |
569 | } |
570 | ||
4e4eef64 MB |
571 | static void kcryptd_io_write(struct dm_crypt_io *io) |
572 | { | |
573 | } | |
574 | ||
395b167c AK |
575 | static void kcryptd_io(struct work_struct *work) |
576 | { | |
577 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
578 | ||
579 | if (bio_data_dir(io->base_bio) == READ) | |
580 | kcryptd_io_read(io); | |
581 | else | |
582 | kcryptd_io_write(io); | |
583 | } | |
584 | ||
585 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
586 | { | |
587 | struct crypt_config *cc = io->target->private; | |
588 | ||
589 | INIT_WORK(&io->work, kcryptd_io); | |
590 | queue_work(cc->io_queue, &io->work); | |
591 | } | |
592 | ||
4e4eef64 MB |
593 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int error) |
594 | { | |
dec1cedf MB |
595 | struct bio *clone = io->ctx.bio_out; |
596 | struct crypt_config *cc = io->target->private; | |
597 | ||
598 | if (unlikely(error < 0)) { | |
599 | crypt_free_buffer_pages(cc, clone); | |
600 | bio_put(clone); | |
601 | io->error = -EIO; | |
dec1cedf MB |
602 | return; |
603 | } | |
604 | ||
605 | /* crypt_convert should have filled the clone bio */ | |
606 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
607 | ||
608 | clone->bi_sector = cc->start + io->sector; | |
609 | io->sector += bio_sectors(clone); | |
899c95d3 MB |
610 | |
611 | atomic_inc(&io->pending); | |
612 | generic_make_request(clone); | |
4e4eef64 MB |
613 | } |
614 | ||
84131db6 | 615 | static void kcryptd_crypt_write_convert_loop(struct dm_crypt_io *io) |
8b004457 MB |
616 | { |
617 | struct crypt_config *cc = io->target->private; | |
8b004457 | 618 | struct bio *clone; |
dec1cedf MB |
619 | unsigned remaining = io->base_bio->bi_size; |
620 | int r; | |
8b004457 | 621 | |
93e605c2 MB |
622 | /* |
623 | * The allocated buffers can be smaller than the whole bio, | |
624 | * so repeat the whole process until all the data can be handled. | |
625 | */ | |
626 | while (remaining) { | |
f97380bc | 627 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 628 | if (unlikely(!clone)) { |
5742fd77 | 629 | io->error = -ENOMEM; |
23541d2d MB |
630 | return; |
631 | } | |
93e605c2 | 632 | |
53017030 MB |
633 | io->ctx.bio_out = clone; |
634 | io->ctx.idx_out = 0; | |
93e605c2 | 635 | |
dec1cedf | 636 | remaining -= clone->bi_size; |
93e605c2 | 637 | |
dec1cedf | 638 | r = crypt_convert(cc, &io->ctx); |
f97380bc | 639 | |
dec1cedf MB |
640 | kcryptd_crypt_write_io_submit(io, r); |
641 | if (unlikely(r < 0)) | |
642 | return; | |
93e605c2 | 643 | |
93e605c2 | 644 | /* out of memory -> run queues */ |
dec1cedf | 645 | if (unlikely(remaining)) |
98221eb7 | 646 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 647 | } |
8b004457 MB |
648 | } |
649 | ||
84131db6 MB |
650 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
651 | { | |
652 | struct crypt_config *cc = io->target->private; | |
653 | ||
899c95d3 MB |
654 | /* |
655 | * Prevent io from disappearing until this function completes. | |
656 | */ | |
84131db6 MB |
657 | atomic_inc(&io->pending); |
658 | ||
659 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, io->sector); | |
660 | kcryptd_crypt_write_convert_loop(io); | |
899c95d3 MB |
661 | |
662 | crypt_dec_pending(io); | |
84131db6 MB |
663 | } |
664 | ||
4e4eef64 | 665 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
666 | { |
667 | if (unlikely(error < 0)) | |
668 | io->error = -EIO; | |
669 | ||
670 | crypt_dec_pending(io); | |
671 | } | |
672 | ||
4e4eef64 | 673 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
674 | { |
675 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 676 | int r = 0; |
1da177e4 | 677 | |
53017030 | 678 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 679 | io->sector); |
1da177e4 | 680 | |
5742fd77 MB |
681 | r = crypt_convert(cc, &io->ctx); |
682 | ||
4e4eef64 | 683 | kcryptd_crypt_read_done(io, r); |
1da177e4 LT |
684 | } |
685 | ||
395b167c | 686 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 687 | { |
028867ac | 688 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 689 | |
cabf08e4 | 690 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 691 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 692 | else |
395b167c | 693 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
694 | } |
695 | ||
395b167c | 696 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 697 | { |
395b167c | 698 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 699 | |
395b167c AK |
700 | INIT_WORK(&io->work, kcryptd_crypt); |
701 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
702 | } |
703 | ||
704 | /* | |
705 | * Decode key from its hex representation | |
706 | */ | |
707 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
708 | { | |
709 | char buffer[3]; | |
710 | char *endp; | |
711 | unsigned int i; | |
712 | ||
713 | buffer[2] = '\0'; | |
714 | ||
8b004457 | 715 | for (i = 0; i < size; i++) { |
1da177e4 LT |
716 | buffer[0] = *hex++; |
717 | buffer[1] = *hex++; | |
718 | ||
719 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
720 | ||
721 | if (endp != &buffer[2]) | |
722 | return -EINVAL; | |
723 | } | |
724 | ||
725 | if (*hex != '\0') | |
726 | return -EINVAL; | |
727 | ||
728 | return 0; | |
729 | } | |
730 | ||
731 | /* | |
732 | * Encode key into its hex representation | |
733 | */ | |
734 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
735 | { | |
736 | unsigned int i; | |
737 | ||
8b004457 | 738 | for (i = 0; i < size; i++) { |
1da177e4 LT |
739 | sprintf(hex, "%02x", *key); |
740 | hex += 2; | |
741 | key++; | |
742 | } | |
743 | } | |
744 | ||
e48d4bbf MB |
745 | static int crypt_set_key(struct crypt_config *cc, char *key) |
746 | { | |
747 | unsigned key_size = strlen(key) >> 1; | |
748 | ||
749 | if (cc->key_size && cc->key_size != key_size) | |
750 | return -EINVAL; | |
751 | ||
752 | cc->key_size = key_size; /* initial settings */ | |
753 | ||
754 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 755 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
756 | return -EINVAL; |
757 | ||
758 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
759 | ||
760 | return 0; | |
761 | } | |
762 | ||
763 | static int crypt_wipe_key(struct crypt_config *cc) | |
764 | { | |
765 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
766 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
767 | return 0; | |
768 | } | |
769 | ||
1da177e4 LT |
770 | /* |
771 | * Construct an encryption mapping: | |
772 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
773 | */ | |
774 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
775 | { | |
776 | struct crypt_config *cc; | |
d1806f6a | 777 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
778 | char *tmp; |
779 | char *cipher; | |
780 | char *chainmode; | |
781 | char *ivmode; | |
782 | char *ivopts; | |
1da177e4 | 783 | unsigned int key_size; |
4ee218cd | 784 | unsigned long long tmpll; |
1da177e4 LT |
785 | |
786 | if (argc != 5) { | |
72d94861 | 787 | ti->error = "Not enough arguments"; |
1da177e4 LT |
788 | return -EINVAL; |
789 | } | |
790 | ||
791 | tmp = argv[0]; | |
792 | cipher = strsep(&tmp, "-"); | |
793 | chainmode = strsep(&tmp, "-"); | |
794 | ivopts = strsep(&tmp, "-"); | |
795 | ivmode = strsep(&ivopts, ":"); | |
796 | ||
797 | if (tmp) | |
72d94861 | 798 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
799 | |
800 | key_size = strlen(argv[1]) >> 1; | |
801 | ||
e48d4bbf | 802 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
803 | if (cc == NULL) { |
804 | ti->error = | |
72d94861 | 805 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
806 | return -ENOMEM; |
807 | } | |
808 | ||
e48d4bbf | 809 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 810 | ti->error = "Error decoding key"; |
636d5786 | 811 | goto bad_cipher; |
1da177e4 LT |
812 | } |
813 | ||
814 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
815 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
816 | chainmode = "cbc"; | |
817 | ivmode = "plain"; | |
818 | } | |
819 | ||
d1806f6a HX |
820 | if (strcmp(chainmode, "ecb") && !ivmode) { |
821 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 822 | goto bad_cipher; |
1da177e4 LT |
823 | } |
824 | ||
d469f841 MB |
825 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
826 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 827 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 828 | goto bad_cipher; |
1da177e4 LT |
829 | } |
830 | ||
d1806f6a HX |
831 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
832 | if (IS_ERR(tfm)) { | |
72d94861 | 833 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 834 | goto bad_cipher; |
1da177e4 | 835 | } |
1da177e4 | 836 | |
d1806f6a HX |
837 | strcpy(cc->cipher, cipher); |
838 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
839 | cc->tfm = tfm; |
840 | ||
841 | /* | |
48527fa7 | 842 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
843 | * See comments at iv code |
844 | */ | |
845 | ||
846 | if (ivmode == NULL) | |
847 | cc->iv_gen_ops = NULL; | |
848 | else if (strcmp(ivmode, "plain") == 0) | |
849 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
850 | else if (strcmp(ivmode, "essiv") == 0) | |
851 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
852 | else if (strcmp(ivmode, "benbi") == 0) |
853 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
854 | else if (strcmp(ivmode, "null") == 0) |
855 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 856 | else { |
72d94861 | 857 | ti->error = "Invalid IV mode"; |
636d5786 | 858 | goto bad_ivmode; |
1da177e4 LT |
859 | } |
860 | ||
861 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
862 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 863 | goto bad_ivmode; |
1da177e4 | 864 | |
d1806f6a HX |
865 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
866 | if (cc->iv_size) | |
1da177e4 | 867 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 868 | cc->iv_size = max(cc->iv_size, |
d469f841 | 869 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 870 | else { |
1da177e4 | 871 | if (cc->iv_gen_ops) { |
72d94861 | 872 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
873 | if (cc->iv_gen_ops->dtr) |
874 | cc->iv_gen_ops->dtr(cc); | |
875 | cc->iv_gen_ops = NULL; | |
876 | } | |
877 | } | |
878 | ||
93d2341c | 879 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 880 | if (!cc->io_pool) { |
72d94861 | 881 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 882 | goto bad_slab_pool; |
1da177e4 LT |
883 | } |
884 | ||
a19b27ce | 885 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 886 | if (!cc->page_pool) { |
72d94861 | 887 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 888 | goto bad_page_pool; |
1da177e4 LT |
889 | } |
890 | ||
5972511b | 891 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
892 | if (!cc->bs) { |
893 | ti->error = "Cannot allocate crypt bioset"; | |
894 | goto bad_bs; | |
895 | } | |
896 | ||
d1806f6a | 897 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 898 | ti->error = "Error setting key"; |
636d5786 | 899 | goto bad_device; |
1da177e4 LT |
900 | } |
901 | ||
4ee218cd | 902 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 903 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 904 | goto bad_device; |
1da177e4 | 905 | } |
4ee218cd | 906 | cc->iv_offset = tmpll; |
1da177e4 | 907 | |
4ee218cd | 908 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 909 | ti->error = "Invalid device sector"; |
636d5786 | 910 | goto bad_device; |
1da177e4 | 911 | } |
4ee218cd | 912 | cc->start = tmpll; |
1da177e4 LT |
913 | |
914 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 915 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 916 | ti->error = "Device lookup failed"; |
636d5786 | 917 | goto bad_device; |
1da177e4 LT |
918 | } |
919 | ||
920 | if (ivmode && cc->iv_gen_ops) { | |
921 | if (ivopts) | |
922 | *(ivopts - 1) = ':'; | |
923 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
924 | if (!cc->iv_mode) { | |
72d94861 | 925 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 926 | goto bad_ivmode_string; |
1da177e4 LT |
927 | } |
928 | strcpy(cc->iv_mode, ivmode); | |
929 | } else | |
930 | cc->iv_mode = NULL; | |
931 | ||
cabf08e4 MB |
932 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
933 | if (!cc->io_queue) { | |
934 | ti->error = "Couldn't create kcryptd io queue"; | |
935 | goto bad_io_queue; | |
936 | } | |
937 | ||
938 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
939 | if (!cc->crypt_queue) { | |
9934a8be | 940 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 941 | goto bad_crypt_queue; |
9934a8be MB |
942 | } |
943 | ||
1da177e4 LT |
944 | ti->private = cc; |
945 | return 0; | |
946 | ||
cabf08e4 MB |
947 | bad_crypt_queue: |
948 | destroy_workqueue(cc->io_queue); | |
949 | bad_io_queue: | |
9934a8be | 950 | kfree(cc->iv_mode); |
636d5786 | 951 | bad_ivmode_string: |
55b42c5a | 952 | dm_put_device(ti, cc->dev); |
636d5786 | 953 | bad_device: |
6a24c718 MB |
954 | bioset_free(cc->bs); |
955 | bad_bs: | |
1da177e4 | 956 | mempool_destroy(cc->page_pool); |
636d5786 | 957 | bad_page_pool: |
1da177e4 | 958 | mempool_destroy(cc->io_pool); |
636d5786 | 959 | bad_slab_pool: |
1da177e4 LT |
960 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
961 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 962 | bad_ivmode: |
d1806f6a | 963 | crypto_free_blkcipher(tfm); |
636d5786 | 964 | bad_cipher: |
9d3520a3 SR |
965 | /* Must zero key material before freeing */ |
966 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
967 | kfree(cc); |
968 | return -EINVAL; | |
969 | } | |
970 | ||
971 | static void crypt_dtr(struct dm_target *ti) | |
972 | { | |
973 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
974 | ||
cabf08e4 MB |
975 | destroy_workqueue(cc->io_queue); |
976 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 977 | |
6a24c718 | 978 | bioset_free(cc->bs); |
1da177e4 LT |
979 | mempool_destroy(cc->page_pool); |
980 | mempool_destroy(cc->io_pool); | |
981 | ||
990a8baf | 982 | kfree(cc->iv_mode); |
1da177e4 LT |
983 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
984 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 985 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 986 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
987 | |
988 | /* Must zero key material before freeing */ | |
989 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
990 | kfree(cc); |
991 | } | |
992 | ||
1da177e4 LT |
993 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
994 | union map_info *map_context) | |
995 | { | |
8b004457 | 996 | struct crypt_config *cc = ti->private; |
028867ac | 997 | struct dm_crypt_io *io; |
1da177e4 | 998 | |
e48d4bbf | 999 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 1000 | io->target = ti; |
8b004457 | 1001 | io->base_bio = bio; |
0c395b0f | 1002 | io->sector = bio->bi_sector - ti->begin; |
cabf08e4 | 1003 | io->error = 0; |
93e605c2 | 1004 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
1005 | |
1006 | if (bio_data_dir(io->base_bio) == READ) | |
1007 | kcryptd_queue_io(io); | |
1008 | else | |
1009 | kcryptd_queue_crypt(io); | |
1da177e4 | 1010 | |
d2a7ad29 | 1011 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1012 | } |
1013 | ||
1014 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1015 | char *result, unsigned int maxlen) | |
1016 | { | |
1017 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1018 | unsigned int sz = 0; |
1019 | ||
1020 | switch (type) { | |
1021 | case STATUSTYPE_INFO: | |
1022 | result[0] = '\0'; | |
1023 | break; | |
1024 | ||
1025 | case STATUSTYPE_TABLE: | |
1da177e4 | 1026 | if (cc->iv_mode) |
37af6560 CS |
1027 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1028 | cc->iv_mode); | |
1da177e4 | 1029 | else |
37af6560 | 1030 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1031 | |
1032 | if (cc->key_size > 0) { | |
1033 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1034 | return -ENOMEM; | |
1035 | ||
1036 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1037 | sz += cc->key_size << 1; | |
1038 | } else { | |
1039 | if (sz >= maxlen) | |
1040 | return -ENOMEM; | |
1041 | result[sz++] = '-'; | |
1042 | } | |
1043 | ||
4ee218cd AM |
1044 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1045 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1046 | break; |
1047 | } | |
1048 | return 0; | |
1049 | } | |
1050 | ||
e48d4bbf MB |
1051 | static void crypt_postsuspend(struct dm_target *ti) |
1052 | { | |
1053 | struct crypt_config *cc = ti->private; | |
1054 | ||
1055 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1056 | } | |
1057 | ||
1058 | static int crypt_preresume(struct dm_target *ti) | |
1059 | { | |
1060 | struct crypt_config *cc = ti->private; | |
1061 | ||
1062 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1063 | DMERR("aborting resume - crypt key is not set."); | |
1064 | return -EAGAIN; | |
1065 | } | |
1066 | ||
1067 | return 0; | |
1068 | } | |
1069 | ||
1070 | static void crypt_resume(struct dm_target *ti) | |
1071 | { | |
1072 | struct crypt_config *cc = ti->private; | |
1073 | ||
1074 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1075 | } | |
1076 | ||
1077 | /* Message interface | |
1078 | * key set <key> | |
1079 | * key wipe | |
1080 | */ | |
1081 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1082 | { | |
1083 | struct crypt_config *cc = ti->private; | |
1084 | ||
1085 | if (argc < 2) | |
1086 | goto error; | |
1087 | ||
1088 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1089 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1090 | DMWARN("not suspended during key manipulation."); | |
1091 | return -EINVAL; | |
1092 | } | |
1093 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1094 | return crypt_set_key(cc, argv[2]); | |
1095 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1096 | return crypt_wipe_key(cc); | |
1097 | } | |
1098 | ||
1099 | error: | |
1100 | DMWARN("unrecognised message received."); | |
1101 | return -EINVAL; | |
1102 | } | |
1103 | ||
1da177e4 LT |
1104 | static struct target_type crypt_target = { |
1105 | .name = "crypt", | |
46b47730 | 1106 | .version= {1, 5, 0}, |
1da177e4 LT |
1107 | .module = THIS_MODULE, |
1108 | .ctr = crypt_ctr, | |
1109 | .dtr = crypt_dtr, | |
1110 | .map = crypt_map, | |
1111 | .status = crypt_status, | |
e48d4bbf MB |
1112 | .postsuspend = crypt_postsuspend, |
1113 | .preresume = crypt_preresume, | |
1114 | .resume = crypt_resume, | |
1115 | .message = crypt_message, | |
1da177e4 LT |
1116 | }; |
1117 | ||
1118 | static int __init dm_crypt_init(void) | |
1119 | { | |
1120 | int r; | |
1121 | ||
028867ac | 1122 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1123 | if (!_crypt_io_pool) |
1124 | return -ENOMEM; | |
1125 | ||
1da177e4 LT |
1126 | r = dm_register_target(&crypt_target); |
1127 | if (r < 0) { | |
72d94861 | 1128 | DMERR("register failed %d", r); |
9934a8be | 1129 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1130 | } |
1131 | ||
1da177e4 LT |
1132 | return r; |
1133 | } | |
1134 | ||
1135 | static void __exit dm_crypt_exit(void) | |
1136 | { | |
1137 | int r = dm_unregister_target(&crypt_target); | |
1138 | ||
1139 | if (r < 0) | |
72d94861 | 1140 | DMERR("unregister failed %d", r); |
1da177e4 | 1141 | |
1da177e4 LT |
1142 | kmem_cache_destroy(_crypt_io_pool); |
1143 | } | |
1144 | ||
1145 | module_init(dm_crypt_init); | |
1146 | module_exit(dm_crypt_exit); | |
1147 | ||
1148 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1149 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1150 | MODULE_LICENSE("GPL"); |