Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
e48d4bbf | 4 | * Copyright (C) 2006 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 LT |
29 | |
30 | /* | |
31 | * per bio private data | |
32 | */ | |
028867ac | 33 | struct dm_crypt_io { |
1da177e4 | 34 | struct dm_target *target; |
8b004457 | 35 | struct bio *base_bio; |
1da177e4 LT |
36 | struct work_struct work; |
37 | atomic_t pending; | |
38 | int error; | |
39 | }; | |
40 | ||
41 | /* | |
42 | * context holding the current state of a multi-part conversion | |
43 | */ | |
44 | struct convert_context { | |
45 | struct bio *bio_in; | |
46 | struct bio *bio_out; | |
47 | unsigned int offset_in; | |
48 | unsigned int offset_out; | |
49 | unsigned int idx_in; | |
50 | unsigned int idx_out; | |
51 | sector_t sector; | |
52 | int write; | |
53 | }; | |
54 | ||
55 | struct crypt_config; | |
56 | ||
57 | struct crypt_iv_operations { | |
58 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 59 | const char *opts); |
1da177e4 LT |
60 | void (*dtr)(struct crypt_config *cc); |
61 | const char *(*status)(struct crypt_config *cc); | |
62 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
63 | }; | |
64 | ||
65 | /* | |
66 | * Crypt: maps a linear range of a block device | |
67 | * and encrypts / decrypts at the same time. | |
68 | */ | |
e48d4bbf | 69 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
70 | struct crypt_config { |
71 | struct dm_dev *dev; | |
72 | sector_t start; | |
73 | ||
74 | /* | |
75 | * pool for per bio private data and | |
76 | * for encryption buffer pages | |
77 | */ | |
78 | mempool_t *io_pool; | |
79 | mempool_t *page_pool; | |
6a24c718 | 80 | struct bio_set *bs; |
1da177e4 | 81 | |
cabf08e4 MB |
82 | struct workqueue_struct *io_queue; |
83 | struct workqueue_struct *crypt_queue; | |
1da177e4 LT |
84 | /* |
85 | * crypto related data | |
86 | */ | |
87 | struct crypt_iv_operations *iv_gen_ops; | |
88 | char *iv_mode; | |
79066ad3 HX |
89 | union { |
90 | struct crypto_cipher *essiv_tfm; | |
91 | int benbi_shift; | |
92 | } iv_gen_private; | |
1da177e4 LT |
93 | sector_t iv_offset; |
94 | unsigned int iv_size; | |
95 | ||
d1806f6a HX |
96 | char cipher[CRYPTO_MAX_ALG_NAME]; |
97 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
98 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 99 | unsigned long flags; |
1da177e4 LT |
100 | unsigned int key_size; |
101 | u8 key[0]; | |
102 | }; | |
103 | ||
6a24c718 | 104 | #define MIN_IOS 16 |
1da177e4 LT |
105 | #define MIN_POOL_PAGES 32 |
106 | #define MIN_BIO_PAGES 8 | |
107 | ||
e18b890b | 108 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 109 | |
028867ac | 110 | static void clone_init(struct dm_crypt_io *, struct bio *); |
027581f3 | 111 | |
1da177e4 LT |
112 | /* |
113 | * Different IV generation algorithms: | |
114 | * | |
3c164bd8 | 115 | * plain: the initial vector is the 32-bit little-endian version of the sector |
1da177e4 LT |
116 | * number, padded with zeros if neccessary. |
117 | * | |
3c164bd8 RS |
118 | * essiv: "encrypted sector|salt initial vector", the sector number is |
119 | * encrypted with the bulk cipher using a salt as key. The salt | |
120 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 121 | * |
48527fa7 RS |
122 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
123 | * (needed for LRW-32-AES and possible other narrow block modes) | |
124 | * | |
46b47730 LN |
125 | * null: the initial vector is always zero. Provides compatibility with |
126 | * obsolete loop_fish2 devices. Do not use for new devices. | |
127 | * | |
1da177e4 LT |
128 | * plumb: unimplemented, see: |
129 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
130 | */ | |
131 | ||
132 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
133 | { | |
134 | memset(iv, 0, cc->iv_size); | |
135 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
136 | ||
137 | return 0; | |
138 | } | |
139 | ||
140 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 141 | const char *opts) |
1da177e4 | 142 | { |
d1806f6a | 143 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
144 | struct crypto_hash *hash_tfm; |
145 | struct hash_desc desc; | |
1da177e4 LT |
146 | struct scatterlist sg; |
147 | unsigned int saltsize; | |
148 | u8 *salt; | |
d1806f6a | 149 | int err; |
1da177e4 LT |
150 | |
151 | if (opts == NULL) { | |
72d94861 | 152 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
153 | return -EINVAL; |
154 | } | |
155 | ||
156 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
157 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
158 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 159 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 160 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
161 | } |
162 | ||
35058687 | 163 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
164 | salt = kmalloc(saltsize, GFP_KERNEL); |
165 | if (salt == NULL) { | |
72d94861 | 166 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 167 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
168 | return -ENOMEM; |
169 | } | |
170 | ||
378f058c | 171 | sg_set_buf(&sg, cc->key, cc->key_size); |
35058687 HX |
172 | desc.tfm = hash_tfm; |
173 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
174 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
175 | crypto_free_hash(hash_tfm); | |
176 | ||
177 | if (err) { | |
178 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 179 | kfree(salt); |
35058687 HX |
180 | return err; |
181 | } | |
1da177e4 LT |
182 | |
183 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
184 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
185 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 186 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 187 | kfree(salt); |
d1806f6a | 188 | return PTR_ERR(essiv_tfm); |
1da177e4 | 189 | } |
d1806f6a HX |
190 | if (crypto_cipher_blocksize(essiv_tfm) != |
191 | crypto_blkcipher_ivsize(cc->tfm)) { | |
72d94861 | 192 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 193 | "not match IV size of block cipher"; |
d1806f6a | 194 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
195 | kfree(salt); |
196 | return -EINVAL; | |
197 | } | |
d1806f6a HX |
198 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
199 | if (err) { | |
72d94861 | 200 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 201 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 202 | kfree(salt); |
d1806f6a | 203 | return err; |
1da177e4 LT |
204 | } |
205 | kfree(salt); | |
206 | ||
79066ad3 | 207 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
208 | return 0; |
209 | } | |
210 | ||
211 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
212 | { | |
79066ad3 HX |
213 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
214 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
215 | } |
216 | ||
217 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
218 | { | |
1da177e4 LT |
219 | memset(iv, 0, cc->iv_size); |
220 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 221 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
222 | return 0; |
223 | } | |
224 | ||
48527fa7 RS |
225 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
226 | const char *opts) | |
227 | { | |
228 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); | |
f0d1b0b3 | 229 | int log = ilog2(bs); |
48527fa7 RS |
230 | |
231 | /* we need to calculate how far we must shift the sector count | |
232 | * to get the cipher block count, we use this shift in _gen */ | |
233 | ||
234 | if (1 << log != bs) { | |
235 | ti->error = "cypher blocksize is not a power of 2"; | |
236 | return -EINVAL; | |
237 | } | |
238 | ||
239 | if (log > 9) { | |
240 | ti->error = "cypher blocksize is > 512"; | |
241 | return -EINVAL; | |
242 | } | |
243 | ||
79066ad3 | 244 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
245 | |
246 | return 0; | |
247 | } | |
248 | ||
249 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
250 | { | |
48527fa7 RS |
251 | } |
252 | ||
253 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
254 | { | |
79066ad3 HX |
255 | __be64 val; |
256 | ||
48527fa7 | 257 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
258 | |
259 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
260 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 261 | |
1da177e4 LT |
262 | return 0; |
263 | } | |
264 | ||
46b47730 LN |
265 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
266 | { | |
267 | memset(iv, 0, cc->iv_size); | |
268 | ||
269 | return 0; | |
270 | } | |
271 | ||
1da177e4 LT |
272 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
273 | .generator = crypt_iv_plain_gen | |
274 | }; | |
275 | ||
276 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
277 | .ctr = crypt_iv_essiv_ctr, | |
278 | .dtr = crypt_iv_essiv_dtr, | |
279 | .generator = crypt_iv_essiv_gen | |
280 | }; | |
281 | ||
48527fa7 RS |
282 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
283 | .ctr = crypt_iv_benbi_ctr, | |
284 | .dtr = crypt_iv_benbi_dtr, | |
285 | .generator = crypt_iv_benbi_gen | |
286 | }; | |
1da177e4 | 287 | |
46b47730 LN |
288 | static struct crypt_iv_operations crypt_iv_null_ops = { |
289 | .generator = crypt_iv_null_gen | |
290 | }; | |
291 | ||
858119e1 | 292 | static int |
1da177e4 LT |
293 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
294 | struct scatterlist *in, unsigned int length, | |
295 | int write, sector_t sector) | |
296 | { | |
45789328 | 297 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
d1806f6a HX |
298 | struct blkcipher_desc desc = { |
299 | .tfm = cc->tfm, | |
300 | .info = iv, | |
301 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, | |
302 | }; | |
1da177e4 LT |
303 | int r; |
304 | ||
305 | if (cc->iv_gen_ops) { | |
306 | r = cc->iv_gen_ops->generator(cc, iv, sector); | |
307 | if (r < 0) | |
308 | return r; | |
309 | ||
310 | if (write) | |
d1806f6a | 311 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
1da177e4 | 312 | else |
d1806f6a | 313 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
1da177e4 LT |
314 | } else { |
315 | if (write) | |
d1806f6a | 316 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
1da177e4 | 317 | else |
d1806f6a | 318 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
1da177e4 LT |
319 | } |
320 | ||
321 | return r; | |
322 | } | |
323 | ||
d469f841 MB |
324 | static void crypt_convert_init(struct crypt_config *cc, |
325 | struct convert_context *ctx, | |
326 | struct bio *bio_out, struct bio *bio_in, | |
327 | sector_t sector, int write) | |
1da177e4 LT |
328 | { |
329 | ctx->bio_in = bio_in; | |
330 | ctx->bio_out = bio_out; | |
331 | ctx->offset_in = 0; | |
332 | ctx->offset_out = 0; | |
333 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
334 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
335 | ctx->sector = sector + cc->iv_offset; | |
336 | ctx->write = write; | |
337 | } | |
338 | ||
339 | /* | |
340 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
341 | */ | |
342 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 343 | struct convert_context *ctx) |
1da177e4 LT |
344 | { |
345 | int r = 0; | |
346 | ||
347 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
348 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
349 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
350 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
351 | struct scatterlist sg_in = { | |
352 | .page = bv_in->bv_page, | |
353 | .offset = bv_in->bv_offset + ctx->offset_in, | |
354 | .length = 1 << SECTOR_SHIFT | |
355 | }; | |
356 | struct scatterlist sg_out = { | |
357 | .page = bv_out->bv_page, | |
358 | .offset = bv_out->bv_offset + ctx->offset_out, | |
359 | .length = 1 << SECTOR_SHIFT | |
360 | }; | |
361 | ||
362 | ctx->offset_in += sg_in.length; | |
363 | if (ctx->offset_in >= bv_in->bv_len) { | |
364 | ctx->offset_in = 0; | |
365 | ctx->idx_in++; | |
366 | } | |
367 | ||
368 | ctx->offset_out += sg_out.length; | |
369 | if (ctx->offset_out >= bv_out->bv_len) { | |
370 | ctx->offset_out = 0; | |
371 | ctx->idx_out++; | |
372 | } | |
373 | ||
374 | r = crypt_convert_scatterlist(cc, &sg_out, &sg_in, sg_in.length, | |
d469f841 | 375 | ctx->write, ctx->sector); |
1da177e4 LT |
376 | if (r < 0) |
377 | break; | |
378 | ||
379 | ctx->sector++; | |
380 | } | |
381 | ||
382 | return r; | |
383 | } | |
384 | ||
d469f841 MB |
385 | static void dm_crypt_bio_destructor(struct bio *bio) |
386 | { | |
028867ac | 387 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
388 | struct crypt_config *cc = io->target->private; |
389 | ||
390 | bio_free(bio, cc->bs); | |
d469f841 | 391 | } |
6a24c718 | 392 | |
1da177e4 LT |
393 | /* |
394 | * Generate a new unfragmented bio with the given size | |
395 | * This should never violate the device limitations | |
396 | * May return a smaller bio when running out of pages | |
397 | */ | |
028867ac | 398 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
1da177e4 | 399 | { |
027581f3 | 400 | struct crypt_config *cc = io->target->private; |
8b004457 | 401 | struct bio *clone; |
1da177e4 | 402 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 403 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
1da177e4 LT |
404 | unsigned int i; |
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++) { |
8b004457 | 413 | struct bio_vec *bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
414 | |
415 | bv->bv_page = mempool_alloc(cc->page_pool, gfp_mask); | |
416 | if (!bv->bv_page) | |
417 | break; | |
418 | ||
419 | /* | |
420 | * if additional pages cannot be allocated without waiting, | |
421 | * return a partially allocated bio, the caller will then try | |
422 | * to allocate additional bios while submitting this partial bio | |
423 | */ | |
f97380bc | 424 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
425 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
426 | ||
427 | bv->bv_offset = 0; | |
428 | if (size > PAGE_SIZE) | |
429 | bv->bv_len = PAGE_SIZE; | |
430 | else | |
431 | bv->bv_len = size; | |
432 | ||
8b004457 MB |
433 | clone->bi_size += bv->bv_len; |
434 | clone->bi_vcnt++; | |
1da177e4 LT |
435 | size -= bv->bv_len; |
436 | } | |
437 | ||
8b004457 MB |
438 | if (!clone->bi_size) { |
439 | bio_put(clone); | |
1da177e4 LT |
440 | return NULL; |
441 | } | |
442 | ||
8b004457 | 443 | return clone; |
1da177e4 LT |
444 | } |
445 | ||
644bd2f0 | 446 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 447 | { |
644bd2f0 | 448 | unsigned int i; |
1da177e4 LT |
449 | struct bio_vec *bv; |
450 | ||
644bd2f0 | 451 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 452 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
453 | BUG_ON(!bv->bv_page); |
454 | mempool_free(bv->bv_page, cc->page_pool); | |
455 | bv->bv_page = NULL; | |
456 | } | |
457 | } | |
458 | ||
459 | /* | |
460 | * One of the bios was finished. Check for completion of | |
461 | * the whole request and correctly clean up the buffer. | |
462 | */ | |
028867ac | 463 | static void dec_pending(struct dm_crypt_io *io, int error) |
1da177e4 LT |
464 | { |
465 | struct crypt_config *cc = (struct crypt_config *) io->target->private; | |
466 | ||
467 | if (error < 0) | |
468 | io->error = error; | |
469 | ||
470 | if (!atomic_dec_and_test(&io->pending)) | |
471 | return; | |
472 | ||
6712ecf8 | 473 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
474 | |
475 | mempool_free(io, cc->io_pool); | |
476 | } | |
477 | ||
478 | /* | |
cabf08e4 | 479 | * kcryptd/kcryptd_io: |
1da177e4 LT |
480 | * |
481 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 482 | * interrupt context. |
cabf08e4 MB |
483 | * |
484 | * kcryptd performs the actual encryption or decryption. | |
485 | * | |
486 | * kcryptd_io performs the IO submission. | |
487 | * | |
488 | * They must be separated as otherwise the final stages could be | |
489 | * starved by new requests which can block in the first stages due | |
490 | * to memory allocation. | |
1da177e4 | 491 | */ |
c4028958 | 492 | static void kcryptd_do_work(struct work_struct *work); |
cabf08e4 | 493 | static void kcryptd_do_crypt(struct work_struct *work); |
1da177e4 | 494 | |
028867ac | 495 | static void kcryptd_queue_io(struct dm_crypt_io *io) |
1da177e4 | 496 | { |
9934a8be MB |
497 | struct crypt_config *cc = io->target->private; |
498 | ||
c4028958 | 499 | INIT_WORK(&io->work, kcryptd_do_work); |
cabf08e4 MB |
500 | queue_work(cc->io_queue, &io->work); |
501 | } | |
502 | ||
503 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) | |
504 | { | |
505 | struct crypt_config *cc = io->target->private; | |
506 | ||
507 | INIT_WORK(&io->work, kcryptd_do_crypt); | |
508 | queue_work(cc->crypt_queue, &io->work); | |
8b004457 MB |
509 | } |
510 | ||
6712ecf8 | 511 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 512 | { |
028867ac | 513 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 MB |
514 | struct crypt_config *cc = io->target->private; |
515 | unsigned read_io = bio_data_dir(clone) == READ; | |
516 | ||
517 | /* | |
6712ecf8 | 518 | * free the processed pages |
8b004457 | 519 | */ |
6712ecf8 | 520 | if (!read_io) { |
644bd2f0 | 521 | crypt_free_buffer_pages(cc, clone); |
8b004457 | 522 | goto out; |
6712ecf8 | 523 | } |
8b004457 MB |
524 | |
525 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE))) { | |
526 | error = -EIO; | |
527 | goto out; | |
528 | } | |
529 | ||
530 | bio_put(clone); | |
cabf08e4 | 531 | kcryptd_queue_crypt(io); |
6712ecf8 | 532 | return; |
8b004457 MB |
533 | |
534 | out: | |
535 | bio_put(clone); | |
536 | dec_pending(io, error); | |
8b004457 MB |
537 | } |
538 | ||
028867ac | 539 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
540 | { |
541 | struct crypt_config *cc = io->target->private; | |
542 | ||
543 | clone->bi_private = io; | |
544 | clone->bi_end_io = crypt_endio; | |
545 | clone->bi_bdev = cc->dev->bdev; | |
546 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 547 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
548 | } |
549 | ||
028867ac | 550 | static void process_read(struct dm_crypt_io *io) |
8b004457 MB |
551 | { |
552 | struct crypt_config *cc = io->target->private; | |
553 | struct bio *base_bio = io->base_bio; | |
554 | struct bio *clone; | |
93e605c2 MB |
555 | sector_t sector = base_bio->bi_sector - io->target->begin; |
556 | ||
557 | atomic_inc(&io->pending); | |
8b004457 MB |
558 | |
559 | /* | |
560 | * The block layer might modify the bvec array, so always | |
561 | * copy the required bvecs because we need the original | |
562 | * one in order to decrypt the whole bio data *afterwards*. | |
563 | */ | |
6a24c718 | 564 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 MB |
565 | if (unlikely(!clone)) { |
566 | dec_pending(io, -ENOMEM); | |
23541d2d | 567 | return; |
93e605c2 | 568 | } |
8b004457 MB |
569 | |
570 | clone_init(io, clone); | |
571 | clone->bi_idx = 0; | |
572 | clone->bi_vcnt = bio_segments(base_bio); | |
573 | clone->bi_size = base_bio->bi_size; | |
93e605c2 | 574 | clone->bi_sector = cc->start + sector; |
8b004457 MB |
575 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
576 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 577 | |
93e605c2 | 578 | generic_make_request(clone); |
8b004457 MB |
579 | } |
580 | ||
028867ac | 581 | static void process_write(struct dm_crypt_io *io) |
8b004457 MB |
582 | { |
583 | struct crypt_config *cc = io->target->private; | |
584 | struct bio *base_bio = io->base_bio; | |
585 | struct bio *clone; | |
93e605c2 MB |
586 | struct convert_context ctx; |
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 | |
93e605c2 | 592 | crypt_convert_init(cc, &ctx, NULL, base_bio, sector, 1); |
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 MB |
600 | if (unlikely(!clone)) { |
601 | dec_pending(io, -ENOMEM); | |
602 | return; | |
603 | } | |
93e605c2 MB |
604 | |
605 | ctx.bio_out = clone; | |
f97380bc | 606 | ctx.idx_out = 0; |
93e605c2 MB |
607 | |
608 | if (unlikely(crypt_convert(cc, &ctx) < 0)) { | |
644bd2f0 | 609 | crypt_free_buffer_pages(cc, clone); |
93e605c2 | 610 | bio_put(clone); |
23541d2d MB |
611 | dec_pending(io, -EIO); |
612 | return; | |
93e605c2 MB |
613 | } |
614 | ||
f97380bc OK |
615 | /* crypt_convert should have filled the clone bio */ |
616 | BUG_ON(ctx.idx_out < clone->bi_vcnt); | |
617 | ||
93e605c2 | 618 | clone->bi_sector = cc->start + sector; |
93e605c2 MB |
619 | remaining -= clone->bi_size; |
620 | sector += bio_sectors(clone); | |
621 | ||
2f9941b6 OK |
622 | /* Grab another reference to the io struct |
623 | * before we kick off the request */ | |
23541d2d MB |
624 | if (remaining) |
625 | atomic_inc(&io->pending); | |
626 | ||
93e605c2 MB |
627 | generic_make_request(clone); |
628 | ||
98221eb7 OK |
629 | /* Do not reference clone after this - it |
630 | * may be gone already. */ | |
631 | ||
93e605c2 MB |
632 | /* out of memory -> run queues */ |
633 | if (remaining) | |
98221eb7 | 634 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 635 | } |
8b004457 MB |
636 | } |
637 | ||
028867ac | 638 | static void process_read_endio(struct dm_crypt_io *io) |
8b004457 MB |
639 | { |
640 | struct crypt_config *cc = io->target->private; | |
1da177e4 | 641 | struct convert_context ctx; |
1da177e4 | 642 | |
8b004457 MB |
643 | crypt_convert_init(cc, &ctx, io->base_bio, io->base_bio, |
644 | io->base_bio->bi_sector - io->target->begin, 0); | |
1da177e4 | 645 | |
8b004457 | 646 | dec_pending(io, crypt_convert(cc, &ctx)); |
1da177e4 LT |
647 | } |
648 | ||
c4028958 | 649 | static void kcryptd_do_work(struct work_struct *work) |
1da177e4 | 650 | { |
028867ac | 651 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 652 | |
cabf08e4 | 653 | if (bio_data_dir(io->base_bio) == READ) |
23541d2d | 654 | process_read(io); |
cabf08e4 MB |
655 | } |
656 | ||
657 | static void kcryptd_do_crypt(struct work_struct *work) | |
658 | { | |
659 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
660 | ||
661 | if (bio_data_dir(io->base_bio) == READ) | |
662 | process_read_endio(io); | |
23541d2d MB |
663 | else |
664 | process_write(io); | |
1da177e4 LT |
665 | } |
666 | ||
667 | /* | |
668 | * Decode key from its hex representation | |
669 | */ | |
670 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
671 | { | |
672 | char buffer[3]; | |
673 | char *endp; | |
674 | unsigned int i; | |
675 | ||
676 | buffer[2] = '\0'; | |
677 | ||
8b004457 | 678 | for (i = 0; i < size; i++) { |
1da177e4 LT |
679 | buffer[0] = *hex++; |
680 | buffer[1] = *hex++; | |
681 | ||
682 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
683 | ||
684 | if (endp != &buffer[2]) | |
685 | return -EINVAL; | |
686 | } | |
687 | ||
688 | if (*hex != '\0') | |
689 | return -EINVAL; | |
690 | ||
691 | return 0; | |
692 | } | |
693 | ||
694 | /* | |
695 | * Encode key into its hex representation | |
696 | */ | |
697 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
698 | { | |
699 | unsigned int i; | |
700 | ||
8b004457 | 701 | for (i = 0; i < size; i++) { |
1da177e4 LT |
702 | sprintf(hex, "%02x", *key); |
703 | hex += 2; | |
704 | key++; | |
705 | } | |
706 | } | |
707 | ||
e48d4bbf MB |
708 | static int crypt_set_key(struct crypt_config *cc, char *key) |
709 | { | |
710 | unsigned key_size = strlen(key) >> 1; | |
711 | ||
712 | if (cc->key_size && cc->key_size != key_size) | |
713 | return -EINVAL; | |
714 | ||
715 | cc->key_size = key_size; /* initial settings */ | |
716 | ||
717 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 718 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
719 | return -EINVAL; |
720 | ||
721 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
722 | ||
723 | return 0; | |
724 | } | |
725 | ||
726 | static int crypt_wipe_key(struct crypt_config *cc) | |
727 | { | |
728 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
729 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
730 | return 0; | |
731 | } | |
732 | ||
1da177e4 LT |
733 | /* |
734 | * Construct an encryption mapping: | |
735 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
736 | */ | |
737 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
738 | { | |
739 | struct crypt_config *cc; | |
d1806f6a | 740 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
741 | char *tmp; |
742 | char *cipher; | |
743 | char *chainmode; | |
744 | char *ivmode; | |
745 | char *ivopts; | |
1da177e4 | 746 | unsigned int key_size; |
4ee218cd | 747 | unsigned long long tmpll; |
1da177e4 LT |
748 | |
749 | if (argc != 5) { | |
72d94861 | 750 | ti->error = "Not enough arguments"; |
1da177e4 LT |
751 | return -EINVAL; |
752 | } | |
753 | ||
754 | tmp = argv[0]; | |
755 | cipher = strsep(&tmp, "-"); | |
756 | chainmode = strsep(&tmp, "-"); | |
757 | ivopts = strsep(&tmp, "-"); | |
758 | ivmode = strsep(&ivopts, ":"); | |
759 | ||
760 | if (tmp) | |
72d94861 | 761 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
762 | |
763 | key_size = strlen(argv[1]) >> 1; | |
764 | ||
e48d4bbf | 765 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
766 | if (cc == NULL) { |
767 | ti->error = | |
72d94861 | 768 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
769 | return -ENOMEM; |
770 | } | |
771 | ||
e48d4bbf | 772 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 773 | ti->error = "Error decoding key"; |
636d5786 | 774 | goto bad_cipher; |
1da177e4 LT |
775 | } |
776 | ||
777 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
778 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
779 | chainmode = "cbc"; | |
780 | ivmode = "plain"; | |
781 | } | |
782 | ||
d1806f6a HX |
783 | if (strcmp(chainmode, "ecb") && !ivmode) { |
784 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 785 | goto bad_cipher; |
1da177e4 LT |
786 | } |
787 | ||
d469f841 MB |
788 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
789 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 790 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 791 | goto bad_cipher; |
1da177e4 LT |
792 | } |
793 | ||
d1806f6a HX |
794 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
795 | if (IS_ERR(tfm)) { | |
72d94861 | 796 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 797 | goto bad_cipher; |
1da177e4 | 798 | } |
1da177e4 | 799 | |
d1806f6a HX |
800 | strcpy(cc->cipher, cipher); |
801 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
802 | cc->tfm = tfm; |
803 | ||
804 | /* | |
48527fa7 | 805 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
806 | * See comments at iv code |
807 | */ | |
808 | ||
809 | if (ivmode == NULL) | |
810 | cc->iv_gen_ops = NULL; | |
811 | else if (strcmp(ivmode, "plain") == 0) | |
812 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
813 | else if (strcmp(ivmode, "essiv") == 0) | |
814 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
815 | else if (strcmp(ivmode, "benbi") == 0) |
816 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
817 | else if (strcmp(ivmode, "null") == 0) |
818 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 819 | else { |
72d94861 | 820 | ti->error = "Invalid IV mode"; |
636d5786 | 821 | goto bad_ivmode; |
1da177e4 LT |
822 | } |
823 | ||
824 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
825 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 826 | goto bad_ivmode; |
1da177e4 | 827 | |
d1806f6a HX |
828 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
829 | if (cc->iv_size) | |
1da177e4 | 830 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 831 | cc->iv_size = max(cc->iv_size, |
d469f841 | 832 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 833 | else { |
1da177e4 | 834 | if (cc->iv_gen_ops) { |
72d94861 | 835 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
836 | if (cc->iv_gen_ops->dtr) |
837 | cc->iv_gen_ops->dtr(cc); | |
838 | cc->iv_gen_ops = NULL; | |
839 | } | |
840 | } | |
841 | ||
93d2341c | 842 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 843 | if (!cc->io_pool) { |
72d94861 | 844 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 845 | goto bad_slab_pool; |
1da177e4 LT |
846 | } |
847 | ||
a19b27ce | 848 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 849 | if (!cc->page_pool) { |
72d94861 | 850 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 851 | goto bad_page_pool; |
1da177e4 LT |
852 | } |
853 | ||
5972511b | 854 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
855 | if (!cc->bs) { |
856 | ti->error = "Cannot allocate crypt bioset"; | |
857 | goto bad_bs; | |
858 | } | |
859 | ||
d1806f6a | 860 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 861 | ti->error = "Error setting key"; |
636d5786 | 862 | goto bad_device; |
1da177e4 LT |
863 | } |
864 | ||
4ee218cd | 865 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 866 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 867 | goto bad_device; |
1da177e4 | 868 | } |
4ee218cd | 869 | cc->iv_offset = tmpll; |
1da177e4 | 870 | |
4ee218cd | 871 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 872 | ti->error = "Invalid device sector"; |
636d5786 | 873 | goto bad_device; |
1da177e4 | 874 | } |
4ee218cd | 875 | cc->start = tmpll; |
1da177e4 LT |
876 | |
877 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 878 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 879 | ti->error = "Device lookup failed"; |
636d5786 | 880 | goto bad_device; |
1da177e4 LT |
881 | } |
882 | ||
883 | if (ivmode && cc->iv_gen_ops) { | |
884 | if (ivopts) | |
885 | *(ivopts - 1) = ':'; | |
886 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
887 | if (!cc->iv_mode) { | |
72d94861 | 888 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 889 | goto bad_ivmode_string; |
1da177e4 LT |
890 | } |
891 | strcpy(cc->iv_mode, ivmode); | |
892 | } else | |
893 | cc->iv_mode = NULL; | |
894 | ||
cabf08e4 MB |
895 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
896 | if (!cc->io_queue) { | |
897 | ti->error = "Couldn't create kcryptd io queue"; | |
898 | goto bad_io_queue; | |
899 | } | |
900 | ||
901 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
902 | if (!cc->crypt_queue) { | |
9934a8be | 903 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 904 | goto bad_crypt_queue; |
9934a8be MB |
905 | } |
906 | ||
1da177e4 LT |
907 | ti->private = cc; |
908 | return 0; | |
909 | ||
cabf08e4 MB |
910 | bad_crypt_queue: |
911 | destroy_workqueue(cc->io_queue); | |
912 | bad_io_queue: | |
9934a8be | 913 | kfree(cc->iv_mode); |
636d5786 | 914 | bad_ivmode_string: |
55b42c5a | 915 | dm_put_device(ti, cc->dev); |
636d5786 | 916 | bad_device: |
6a24c718 MB |
917 | bioset_free(cc->bs); |
918 | bad_bs: | |
1da177e4 | 919 | mempool_destroy(cc->page_pool); |
636d5786 | 920 | bad_page_pool: |
1da177e4 | 921 | mempool_destroy(cc->io_pool); |
636d5786 | 922 | bad_slab_pool: |
1da177e4 LT |
923 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
924 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 925 | bad_ivmode: |
d1806f6a | 926 | crypto_free_blkcipher(tfm); |
636d5786 | 927 | bad_cipher: |
9d3520a3 SR |
928 | /* Must zero key material before freeing */ |
929 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
930 | kfree(cc); |
931 | return -EINVAL; | |
932 | } | |
933 | ||
934 | static void crypt_dtr(struct dm_target *ti) | |
935 | { | |
936 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
937 | ||
cabf08e4 MB |
938 | destroy_workqueue(cc->io_queue); |
939 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 940 | |
6a24c718 | 941 | bioset_free(cc->bs); |
1da177e4 LT |
942 | mempool_destroy(cc->page_pool); |
943 | mempool_destroy(cc->io_pool); | |
944 | ||
990a8baf | 945 | kfree(cc->iv_mode); |
1da177e4 LT |
946 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
947 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 948 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 949 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
950 | |
951 | /* Must zero key material before freeing */ | |
952 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
953 | kfree(cc); |
954 | } | |
955 | ||
1da177e4 LT |
956 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
957 | union map_info *map_context) | |
958 | { | |
8b004457 | 959 | struct crypt_config *cc = ti->private; |
028867ac | 960 | struct dm_crypt_io *io; |
1da177e4 | 961 | |
e48d4bbf | 962 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 963 | io->target = ti; |
8b004457 | 964 | io->base_bio = bio; |
cabf08e4 | 965 | io->error = 0; |
93e605c2 | 966 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
967 | |
968 | if (bio_data_dir(io->base_bio) == READ) | |
969 | kcryptd_queue_io(io); | |
970 | else | |
971 | kcryptd_queue_crypt(io); | |
1da177e4 | 972 | |
d2a7ad29 | 973 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
974 | } |
975 | ||
976 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
977 | char *result, unsigned int maxlen) | |
978 | { | |
979 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
980 | unsigned int sz = 0; |
981 | ||
982 | switch (type) { | |
983 | case STATUSTYPE_INFO: | |
984 | result[0] = '\0'; | |
985 | break; | |
986 | ||
987 | case STATUSTYPE_TABLE: | |
1da177e4 | 988 | if (cc->iv_mode) |
37af6560 CS |
989 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
990 | cc->iv_mode); | |
1da177e4 | 991 | else |
37af6560 | 992 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
993 | |
994 | if (cc->key_size > 0) { | |
995 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
996 | return -ENOMEM; | |
997 | ||
998 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
999 | sz += cc->key_size << 1; | |
1000 | } else { | |
1001 | if (sz >= maxlen) | |
1002 | return -ENOMEM; | |
1003 | result[sz++] = '-'; | |
1004 | } | |
1005 | ||
4ee218cd AM |
1006 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1007 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1008 | break; |
1009 | } | |
1010 | return 0; | |
1011 | } | |
1012 | ||
e48d4bbf MB |
1013 | static void crypt_postsuspend(struct dm_target *ti) |
1014 | { | |
1015 | struct crypt_config *cc = ti->private; | |
1016 | ||
1017 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1018 | } | |
1019 | ||
1020 | static int crypt_preresume(struct dm_target *ti) | |
1021 | { | |
1022 | struct crypt_config *cc = ti->private; | |
1023 | ||
1024 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1025 | DMERR("aborting resume - crypt key is not set."); | |
1026 | return -EAGAIN; | |
1027 | } | |
1028 | ||
1029 | return 0; | |
1030 | } | |
1031 | ||
1032 | static void crypt_resume(struct dm_target *ti) | |
1033 | { | |
1034 | struct crypt_config *cc = ti->private; | |
1035 | ||
1036 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1037 | } | |
1038 | ||
1039 | /* Message interface | |
1040 | * key set <key> | |
1041 | * key wipe | |
1042 | */ | |
1043 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1044 | { | |
1045 | struct crypt_config *cc = ti->private; | |
1046 | ||
1047 | if (argc < 2) | |
1048 | goto error; | |
1049 | ||
1050 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1051 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1052 | DMWARN("not suspended during key manipulation."); | |
1053 | return -EINVAL; | |
1054 | } | |
1055 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1056 | return crypt_set_key(cc, argv[2]); | |
1057 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1058 | return crypt_wipe_key(cc); | |
1059 | } | |
1060 | ||
1061 | error: | |
1062 | DMWARN("unrecognised message received."); | |
1063 | return -EINVAL; | |
1064 | } | |
1065 | ||
1da177e4 LT |
1066 | static struct target_type crypt_target = { |
1067 | .name = "crypt", | |
46b47730 | 1068 | .version= {1, 5, 0}, |
1da177e4 LT |
1069 | .module = THIS_MODULE, |
1070 | .ctr = crypt_ctr, | |
1071 | .dtr = crypt_dtr, | |
1072 | .map = crypt_map, | |
1073 | .status = crypt_status, | |
e48d4bbf MB |
1074 | .postsuspend = crypt_postsuspend, |
1075 | .preresume = crypt_preresume, | |
1076 | .resume = crypt_resume, | |
1077 | .message = crypt_message, | |
1da177e4 LT |
1078 | }; |
1079 | ||
1080 | static int __init dm_crypt_init(void) | |
1081 | { | |
1082 | int r; | |
1083 | ||
028867ac | 1084 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1085 | if (!_crypt_io_pool) |
1086 | return -ENOMEM; | |
1087 | ||
1da177e4 LT |
1088 | r = dm_register_target(&crypt_target); |
1089 | if (r < 0) { | |
72d94861 | 1090 | DMERR("register failed %d", r); |
9934a8be | 1091 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1092 | } |
1093 | ||
1da177e4 LT |
1094 | return r; |
1095 | } | |
1096 | ||
1097 | static void __exit dm_crypt_exit(void) | |
1098 | { | |
1099 | int r = dm_unregister_target(&crypt_target); | |
1100 | ||
1101 | if (r < 0) | |
72d94861 | 1102 | DMERR("unregister failed %d", r); |
1da177e4 | 1103 | |
1da177e4 LT |
1104 | kmem_cache_destroy(_crypt_io_pool); |
1105 | } | |
1106 | ||
1107 | module_init(dm_crypt_init); | |
1108 | module_exit(dm_crypt_exit); | |
1109 | ||
1110 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1111 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1112 | MODULE_LICENSE("GPL"); |