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Commit | Line | Data |
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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 | 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; | |
41 | int write; | |
42 | }; | |
43 | ||
53017030 MB |
44 | /* |
45 | * per bio private data | |
46 | */ | |
47 | struct dm_crypt_io { | |
48 | struct dm_target *target; | |
49 | struct bio *base_bio; | |
50 | struct work_struct work; | |
51 | ||
52 | struct convert_context ctx; | |
53 | ||
54 | atomic_t pending; | |
55 | int error; | |
56 | }; | |
57 | ||
1da177e4 LT |
58 | struct crypt_config; |
59 | ||
60 | struct crypt_iv_operations { | |
61 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 62 | const char *opts); |
1da177e4 LT |
63 | void (*dtr)(struct crypt_config *cc); |
64 | const char *(*status)(struct crypt_config *cc); | |
65 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
66 | }; | |
67 | ||
68 | /* | |
69 | * Crypt: maps a linear range of a block device | |
70 | * and encrypts / decrypts at the same time. | |
71 | */ | |
e48d4bbf | 72 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
73 | struct crypt_config { |
74 | struct dm_dev *dev; | |
75 | sector_t start; | |
76 | ||
77 | /* | |
78 | * pool for per bio private data and | |
79 | * for encryption buffer pages | |
80 | */ | |
81 | mempool_t *io_pool; | |
82 | mempool_t *page_pool; | |
6a24c718 | 83 | struct bio_set *bs; |
1da177e4 | 84 | |
cabf08e4 MB |
85 | struct workqueue_struct *io_queue; |
86 | struct workqueue_struct *crypt_queue; | |
1da177e4 LT |
87 | /* |
88 | * crypto related data | |
89 | */ | |
90 | struct crypt_iv_operations *iv_gen_ops; | |
91 | char *iv_mode; | |
79066ad3 HX |
92 | union { |
93 | struct crypto_cipher *essiv_tfm; | |
94 | int benbi_shift; | |
95 | } iv_gen_private; | |
1da177e4 LT |
96 | sector_t iv_offset; |
97 | unsigned int iv_size; | |
98 | ||
d1806f6a HX |
99 | char cipher[CRYPTO_MAX_ALG_NAME]; |
100 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
101 | struct crypto_blkcipher *tfm; | |
e48d4bbf | 102 | unsigned long flags; |
1da177e4 LT |
103 | unsigned int key_size; |
104 | u8 key[0]; | |
105 | }; | |
106 | ||
6a24c718 | 107 | #define MIN_IOS 16 |
1da177e4 LT |
108 | #define MIN_POOL_PAGES 32 |
109 | #define MIN_BIO_PAGES 8 | |
110 | ||
e18b890b | 111 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 112 | |
028867ac | 113 | static void clone_init(struct dm_crypt_io *, struct bio *); |
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, | |
330 | sector_t sector, int write) | |
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; | |
339 | ctx->write = write; | |
340 | } | |
341 | ||
342 | /* | |
343 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
344 | */ | |
345 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 346 | struct convert_context *ctx) |
1da177e4 LT |
347 | { |
348 | int r = 0; | |
349 | ||
350 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && | |
351 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
352 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
353 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
45711f1a JA |
354 | struct scatterlist sg_in, sg_out; |
355 | ||
356 | sg_init_table(&sg_in, 1); | |
642f1490 | 357 | sg_set_page(&sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, bv_in->bv_offset + ctx->offset_in); |
45711f1a JA |
358 | |
359 | sg_init_table(&sg_out, 1); | |
642f1490 | 360 | sg_set_page(&sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, bv_out->bv_offset + ctx->offset_out); |
1da177e4 LT |
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; |
91e10625 MB |
404 | unsigned i, len; |
405 | struct page *page; | |
1da177e4 | 406 | |
2f9941b6 | 407 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 408 | if (!clone) |
1da177e4 | 409 | return NULL; |
1da177e4 | 410 | |
027581f3 | 411 | clone_init(io, clone); |
6a24c718 | 412 | |
f97380bc | 413 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 MB |
414 | page = mempool_alloc(cc->page_pool, gfp_mask); |
415 | if (!page) | |
1da177e4 LT |
416 | break; |
417 | ||
418 | /* | |
419 | * if additional pages cannot be allocated without waiting, | |
420 | * return a partially allocated bio, the caller will then try | |
421 | * to allocate additional bios while submitting this partial bio | |
422 | */ | |
f97380bc | 423 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
424 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
425 | ||
91e10625 MB |
426 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
427 | ||
428 | if (!bio_add_page(clone, page, len, 0)) { | |
429 | mempool_free(page, cc->page_pool); | |
430 | break; | |
431 | } | |
1da177e4 | 432 | |
91e10625 | 433 | size -= len; |
1da177e4 LT |
434 | } |
435 | ||
8b004457 MB |
436 | if (!clone->bi_size) { |
437 | bio_put(clone); | |
1da177e4 LT |
438 | return NULL; |
439 | } | |
440 | ||
8b004457 | 441 | return clone; |
1da177e4 LT |
442 | } |
443 | ||
644bd2f0 | 444 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 445 | { |
644bd2f0 | 446 | unsigned int i; |
1da177e4 LT |
447 | struct bio_vec *bv; |
448 | ||
644bd2f0 | 449 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 450 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
451 | BUG_ON(!bv->bv_page); |
452 | mempool_free(bv->bv_page, cc->page_pool); | |
453 | bv->bv_page = NULL; | |
454 | } | |
455 | } | |
456 | ||
457 | /* | |
458 | * One of the bios was finished. Check for completion of | |
459 | * the whole request and correctly clean up the buffer. | |
460 | */ | |
80fd6626 | 461 | static void crypt_dec_pending(struct dm_crypt_io *io, int error) |
1da177e4 LT |
462 | { |
463 | struct crypt_config *cc = (struct crypt_config *) io->target->private; | |
464 | ||
465 | if (error < 0) | |
466 | io->error = error; | |
467 | ||
468 | if (!atomic_dec_and_test(&io->pending)) | |
469 | return; | |
470 | ||
6712ecf8 | 471 | bio_endio(io->base_bio, io->error); |
1da177e4 LT |
472 | |
473 | mempool_free(io, cc->io_pool); | |
474 | } | |
475 | ||
476 | /* | |
cabf08e4 | 477 | * kcryptd/kcryptd_io: |
1da177e4 LT |
478 | * |
479 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 480 | * interrupt context. |
cabf08e4 MB |
481 | * |
482 | * kcryptd performs the actual encryption or decryption. | |
483 | * | |
484 | * kcryptd_io performs the IO submission. | |
485 | * | |
486 | * They must be separated as otherwise the final stages could be | |
487 | * starved by new requests which can block in the first stages due | |
488 | * to memory allocation. | |
1da177e4 | 489 | */ |
c4028958 | 490 | static void kcryptd_do_work(struct work_struct *work); |
cabf08e4 | 491 | static void kcryptd_do_crypt(struct work_struct *work); |
1da177e4 | 492 | |
028867ac | 493 | static void kcryptd_queue_io(struct dm_crypt_io *io) |
1da177e4 | 494 | { |
9934a8be MB |
495 | struct crypt_config *cc = io->target->private; |
496 | ||
c4028958 | 497 | INIT_WORK(&io->work, kcryptd_do_work); |
cabf08e4 MB |
498 | queue_work(cc->io_queue, &io->work); |
499 | } | |
500 | ||
501 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) | |
502 | { | |
503 | struct crypt_config *cc = io->target->private; | |
504 | ||
505 | INIT_WORK(&io->work, kcryptd_do_crypt); | |
506 | queue_work(cc->crypt_queue, &io->work); | |
8b004457 MB |
507 | } |
508 | ||
6712ecf8 | 509 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 510 | { |
028867ac | 511 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 MB |
512 | struct crypt_config *cc = io->target->private; |
513 | unsigned read_io = bio_data_dir(clone) == READ; | |
514 | ||
adfe4770 MB |
515 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
516 | error = -EIO; | |
517 | ||
8b004457 | 518 | /* |
6712ecf8 | 519 | * free the processed pages |
8b004457 | 520 | */ |
6712ecf8 | 521 | if (!read_io) { |
644bd2f0 | 522 | crypt_free_buffer_pages(cc, clone); |
8b004457 | 523 | goto out; |
6712ecf8 | 524 | } |
8b004457 | 525 | |
adfe4770 | 526 | if (unlikely(error)) |
8b004457 | 527 | goto out; |
8b004457 MB |
528 | |
529 | bio_put(clone); | |
cabf08e4 | 530 | kcryptd_queue_crypt(io); |
6712ecf8 | 531 | return; |
8b004457 MB |
532 | |
533 | out: | |
534 | bio_put(clone); | |
80fd6626 | 535 | crypt_dec_pending(io, error); |
8b004457 MB |
536 | } |
537 | ||
028867ac | 538 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
539 | { |
540 | struct crypt_config *cc = io->target->private; | |
541 | ||
542 | clone->bi_private = io; | |
543 | clone->bi_end_io = crypt_endio; | |
544 | clone->bi_bdev = cc->dev->bdev; | |
545 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 546 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
547 | } |
548 | ||
028867ac | 549 | static void process_read(struct dm_crypt_io *io) |
8b004457 MB |
550 | { |
551 | struct crypt_config *cc = io->target->private; | |
552 | struct bio *base_bio = io->base_bio; | |
553 | struct bio *clone; | |
93e605c2 MB |
554 | sector_t sector = base_bio->bi_sector - io->target->begin; |
555 | ||
556 | atomic_inc(&io->pending); | |
8b004457 MB |
557 | |
558 | /* | |
559 | * The block layer might modify the bvec array, so always | |
560 | * copy the required bvecs because we need the original | |
561 | * one in order to decrypt the whole bio data *afterwards*. | |
562 | */ | |
6a24c718 | 563 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 564 | if (unlikely(!clone)) { |
80fd6626 | 565 | crypt_dec_pending(io, -ENOMEM); |
23541d2d | 566 | return; |
93e605c2 | 567 | } |
8b004457 MB |
568 | |
569 | clone_init(io, clone); | |
570 | clone->bi_idx = 0; | |
571 | clone->bi_vcnt = bio_segments(base_bio); | |
572 | clone->bi_size = base_bio->bi_size; | |
93e605c2 | 573 | clone->bi_sector = cc->start + sector; |
8b004457 MB |
574 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
575 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 576 | |
93e605c2 | 577 | generic_make_request(clone); |
8b004457 MB |
578 | } |
579 | ||
028867ac | 580 | static void process_write(struct dm_crypt_io *io) |
8b004457 MB |
581 | { |
582 | struct crypt_config *cc = io->target->private; | |
583 | struct bio *base_bio = io->base_bio; | |
584 | struct bio *clone; | |
93e605c2 MB |
585 | unsigned remaining = base_bio->bi_size; |
586 | sector_t sector = base_bio->bi_sector - io->target->begin; | |
8b004457 | 587 | |
93e605c2 | 588 | atomic_inc(&io->pending); |
8b004457 | 589 | |
53017030 | 590 | crypt_convert_init(cc, &io->ctx, NULL, base_bio, sector, 1); |
8b004457 | 591 | |
93e605c2 MB |
592 | /* |
593 | * The allocated buffers can be smaller than the whole bio, | |
594 | * so repeat the whole process until all the data can be handled. | |
595 | */ | |
596 | while (remaining) { | |
f97380bc | 597 | clone = crypt_alloc_buffer(io, remaining); |
23541d2d | 598 | if (unlikely(!clone)) { |
80fd6626 | 599 | crypt_dec_pending(io, -ENOMEM); |
23541d2d MB |
600 | return; |
601 | } | |
93e605c2 | 602 | |
53017030 MB |
603 | io->ctx.bio_out = clone; |
604 | io->ctx.idx_out = 0; | |
93e605c2 | 605 | |
53017030 | 606 | if (unlikely(crypt_convert(cc, &io->ctx) < 0)) { |
644bd2f0 | 607 | crypt_free_buffer_pages(cc, clone); |
93e605c2 | 608 | bio_put(clone); |
80fd6626 | 609 | crypt_dec_pending(io, -EIO); |
23541d2d | 610 | return; |
93e605c2 MB |
611 | } |
612 | ||
f97380bc | 613 | /* crypt_convert should have filled the clone bio */ |
53017030 | 614 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); |
f97380bc | 615 | |
93e605c2 | 616 | clone->bi_sector = cc->start + sector; |
93e605c2 MB |
617 | remaining -= clone->bi_size; |
618 | sector += bio_sectors(clone); | |
619 | ||
2f9941b6 OK |
620 | /* Grab another reference to the io struct |
621 | * before we kick off the request */ | |
23541d2d MB |
622 | if (remaining) |
623 | atomic_inc(&io->pending); | |
624 | ||
93e605c2 MB |
625 | generic_make_request(clone); |
626 | ||
98221eb7 OK |
627 | /* Do not reference clone after this - it |
628 | * may be gone already. */ | |
629 | ||
93e605c2 MB |
630 | /* out of memory -> run queues */ |
631 | if (remaining) | |
98221eb7 | 632 | congestion_wait(WRITE, HZ/100); |
93e605c2 | 633 | } |
8b004457 MB |
634 | } |
635 | ||
028867ac | 636 | static void process_read_endio(struct dm_crypt_io *io) |
8b004457 MB |
637 | { |
638 | struct crypt_config *cc = io->target->private; | |
1da177e4 | 639 | |
53017030 | 640 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
8b004457 | 641 | io->base_bio->bi_sector - io->target->begin, 0); |
1da177e4 | 642 | |
53017030 | 643 | crypt_dec_pending(io, crypt_convert(cc, &io->ctx)); |
1da177e4 LT |
644 | } |
645 | ||
c4028958 | 646 | static void kcryptd_do_work(struct work_struct *work) |
1da177e4 | 647 | { |
028867ac | 648 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 649 | |
cabf08e4 | 650 | if (bio_data_dir(io->base_bio) == READ) |
23541d2d | 651 | process_read(io); |
cabf08e4 MB |
652 | } |
653 | ||
654 | static void kcryptd_do_crypt(struct work_struct *work) | |
655 | { | |
656 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
657 | ||
658 | if (bio_data_dir(io->base_bio) == READ) | |
659 | process_read_endio(io); | |
23541d2d MB |
660 | else |
661 | process_write(io); | |
1da177e4 LT |
662 | } |
663 | ||
664 | /* | |
665 | * Decode key from its hex representation | |
666 | */ | |
667 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
668 | { | |
669 | char buffer[3]; | |
670 | char *endp; | |
671 | unsigned int i; | |
672 | ||
673 | buffer[2] = '\0'; | |
674 | ||
8b004457 | 675 | for (i = 0; i < size; i++) { |
1da177e4 LT |
676 | buffer[0] = *hex++; |
677 | buffer[1] = *hex++; | |
678 | ||
679 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
680 | ||
681 | if (endp != &buffer[2]) | |
682 | return -EINVAL; | |
683 | } | |
684 | ||
685 | if (*hex != '\0') | |
686 | return -EINVAL; | |
687 | ||
688 | return 0; | |
689 | } | |
690 | ||
691 | /* | |
692 | * Encode key into its hex representation | |
693 | */ | |
694 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
695 | { | |
696 | unsigned int i; | |
697 | ||
8b004457 | 698 | for (i = 0; i < size; i++) { |
1da177e4 LT |
699 | sprintf(hex, "%02x", *key); |
700 | hex += 2; | |
701 | key++; | |
702 | } | |
703 | } | |
704 | ||
e48d4bbf MB |
705 | static int crypt_set_key(struct crypt_config *cc, char *key) |
706 | { | |
707 | unsigned key_size = strlen(key) >> 1; | |
708 | ||
709 | if (cc->key_size && cc->key_size != key_size) | |
710 | return -EINVAL; | |
711 | ||
712 | cc->key_size = key_size; /* initial settings */ | |
713 | ||
714 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 715 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
716 | return -EINVAL; |
717 | ||
718 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
719 | ||
720 | return 0; | |
721 | } | |
722 | ||
723 | static int crypt_wipe_key(struct crypt_config *cc) | |
724 | { | |
725 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
726 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
727 | return 0; | |
728 | } | |
729 | ||
1da177e4 LT |
730 | /* |
731 | * Construct an encryption mapping: | |
732 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
733 | */ | |
734 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
735 | { | |
736 | struct crypt_config *cc; | |
d1806f6a | 737 | struct crypto_blkcipher *tfm; |
1da177e4 LT |
738 | char *tmp; |
739 | char *cipher; | |
740 | char *chainmode; | |
741 | char *ivmode; | |
742 | char *ivopts; | |
1da177e4 | 743 | unsigned int key_size; |
4ee218cd | 744 | unsigned long long tmpll; |
1da177e4 LT |
745 | |
746 | if (argc != 5) { | |
72d94861 | 747 | ti->error = "Not enough arguments"; |
1da177e4 LT |
748 | return -EINVAL; |
749 | } | |
750 | ||
751 | tmp = argv[0]; | |
752 | cipher = strsep(&tmp, "-"); | |
753 | chainmode = strsep(&tmp, "-"); | |
754 | ivopts = strsep(&tmp, "-"); | |
755 | ivmode = strsep(&ivopts, ":"); | |
756 | ||
757 | if (tmp) | |
72d94861 | 758 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
759 | |
760 | key_size = strlen(argv[1]) >> 1; | |
761 | ||
e48d4bbf | 762 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
763 | if (cc == NULL) { |
764 | ti->error = | |
72d94861 | 765 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
766 | return -ENOMEM; |
767 | } | |
768 | ||
e48d4bbf | 769 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 770 | ti->error = "Error decoding key"; |
636d5786 | 771 | goto bad_cipher; |
1da177e4 LT |
772 | } |
773 | ||
774 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
775 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
776 | chainmode = "cbc"; | |
777 | ivmode = "plain"; | |
778 | } | |
779 | ||
d1806f6a HX |
780 | if (strcmp(chainmode, "ecb") && !ivmode) { |
781 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 782 | goto bad_cipher; |
1da177e4 LT |
783 | } |
784 | ||
d469f841 MB |
785 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
786 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 787 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 788 | goto bad_cipher; |
1da177e4 LT |
789 | } |
790 | ||
d1806f6a HX |
791 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
792 | if (IS_ERR(tfm)) { | |
72d94861 | 793 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 794 | goto bad_cipher; |
1da177e4 | 795 | } |
1da177e4 | 796 | |
d1806f6a HX |
797 | strcpy(cc->cipher, cipher); |
798 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
799 | cc->tfm = tfm; |
800 | ||
801 | /* | |
48527fa7 | 802 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
803 | * See comments at iv code |
804 | */ | |
805 | ||
806 | if (ivmode == NULL) | |
807 | cc->iv_gen_ops = NULL; | |
808 | else if (strcmp(ivmode, "plain") == 0) | |
809 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
810 | else if (strcmp(ivmode, "essiv") == 0) | |
811 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
812 | else if (strcmp(ivmode, "benbi") == 0) |
813 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
814 | else if (strcmp(ivmode, "null") == 0) |
815 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 816 | else { |
72d94861 | 817 | ti->error = "Invalid IV mode"; |
636d5786 | 818 | goto bad_ivmode; |
1da177e4 LT |
819 | } |
820 | ||
821 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
822 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 823 | goto bad_ivmode; |
1da177e4 | 824 | |
d1806f6a HX |
825 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
826 | if (cc->iv_size) | |
1da177e4 | 827 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 828 | cc->iv_size = max(cc->iv_size, |
d469f841 | 829 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 830 | else { |
1da177e4 | 831 | if (cc->iv_gen_ops) { |
72d94861 | 832 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
833 | if (cc->iv_gen_ops->dtr) |
834 | cc->iv_gen_ops->dtr(cc); | |
835 | cc->iv_gen_ops = NULL; | |
836 | } | |
837 | } | |
838 | ||
93d2341c | 839 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 840 | if (!cc->io_pool) { |
72d94861 | 841 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 842 | goto bad_slab_pool; |
1da177e4 LT |
843 | } |
844 | ||
a19b27ce | 845 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 846 | if (!cc->page_pool) { |
72d94861 | 847 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 848 | goto bad_page_pool; |
1da177e4 LT |
849 | } |
850 | ||
5972511b | 851 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
6a24c718 MB |
852 | if (!cc->bs) { |
853 | ti->error = "Cannot allocate crypt bioset"; | |
854 | goto bad_bs; | |
855 | } | |
856 | ||
d1806f6a | 857 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 858 | ti->error = "Error setting key"; |
636d5786 | 859 | goto bad_device; |
1da177e4 LT |
860 | } |
861 | ||
4ee218cd | 862 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 863 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 864 | goto bad_device; |
1da177e4 | 865 | } |
4ee218cd | 866 | cc->iv_offset = tmpll; |
1da177e4 | 867 | |
4ee218cd | 868 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 869 | ti->error = "Invalid device sector"; |
636d5786 | 870 | goto bad_device; |
1da177e4 | 871 | } |
4ee218cd | 872 | cc->start = tmpll; |
1da177e4 LT |
873 | |
874 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 875 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 876 | ti->error = "Device lookup failed"; |
636d5786 | 877 | goto bad_device; |
1da177e4 LT |
878 | } |
879 | ||
880 | if (ivmode && cc->iv_gen_ops) { | |
881 | if (ivopts) | |
882 | *(ivopts - 1) = ':'; | |
883 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
884 | if (!cc->iv_mode) { | |
72d94861 | 885 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 886 | goto bad_ivmode_string; |
1da177e4 LT |
887 | } |
888 | strcpy(cc->iv_mode, ivmode); | |
889 | } else | |
890 | cc->iv_mode = NULL; | |
891 | ||
cabf08e4 MB |
892 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
893 | if (!cc->io_queue) { | |
894 | ti->error = "Couldn't create kcryptd io queue"; | |
895 | goto bad_io_queue; | |
896 | } | |
897 | ||
898 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
899 | if (!cc->crypt_queue) { | |
9934a8be | 900 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 901 | goto bad_crypt_queue; |
9934a8be MB |
902 | } |
903 | ||
1da177e4 LT |
904 | ti->private = cc; |
905 | return 0; | |
906 | ||
cabf08e4 MB |
907 | bad_crypt_queue: |
908 | destroy_workqueue(cc->io_queue); | |
909 | bad_io_queue: | |
9934a8be | 910 | kfree(cc->iv_mode); |
636d5786 | 911 | bad_ivmode_string: |
55b42c5a | 912 | dm_put_device(ti, cc->dev); |
636d5786 | 913 | bad_device: |
6a24c718 MB |
914 | bioset_free(cc->bs); |
915 | bad_bs: | |
1da177e4 | 916 | mempool_destroy(cc->page_pool); |
636d5786 | 917 | bad_page_pool: |
1da177e4 | 918 | mempool_destroy(cc->io_pool); |
636d5786 | 919 | bad_slab_pool: |
1da177e4 LT |
920 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
921 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 922 | bad_ivmode: |
d1806f6a | 923 | crypto_free_blkcipher(tfm); |
636d5786 | 924 | bad_cipher: |
9d3520a3 SR |
925 | /* Must zero key material before freeing */ |
926 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
927 | kfree(cc); |
928 | return -EINVAL; | |
929 | } | |
930 | ||
931 | static void crypt_dtr(struct dm_target *ti) | |
932 | { | |
933 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
934 | ||
cabf08e4 MB |
935 | destroy_workqueue(cc->io_queue); |
936 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 937 | |
6a24c718 | 938 | bioset_free(cc->bs); |
1da177e4 LT |
939 | mempool_destroy(cc->page_pool); |
940 | mempool_destroy(cc->io_pool); | |
941 | ||
990a8baf | 942 | kfree(cc->iv_mode); |
1da177e4 LT |
943 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
944 | cc->iv_gen_ops->dtr(cc); | |
d1806f6a | 945 | crypto_free_blkcipher(cc->tfm); |
1da177e4 | 946 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
947 | |
948 | /* Must zero key material before freeing */ | |
949 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); | |
1da177e4 LT |
950 | kfree(cc); |
951 | } | |
952 | ||
1da177e4 LT |
953 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
954 | union map_info *map_context) | |
955 | { | |
8b004457 | 956 | struct crypt_config *cc = ti->private; |
028867ac | 957 | struct dm_crypt_io *io; |
1da177e4 | 958 | |
e48d4bbf | 959 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
1da177e4 | 960 | io->target = ti; |
8b004457 | 961 | io->base_bio = bio; |
cabf08e4 | 962 | io->error = 0; |
93e605c2 | 963 | atomic_set(&io->pending, 0); |
cabf08e4 MB |
964 | |
965 | if (bio_data_dir(io->base_bio) == READ) | |
966 | kcryptd_queue_io(io); | |
967 | else | |
968 | kcryptd_queue_crypt(io); | |
1da177e4 | 969 | |
d2a7ad29 | 970 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
971 | } |
972 | ||
973 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
974 | char *result, unsigned int maxlen) | |
975 | { | |
976 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
977 | unsigned int sz = 0; |
978 | ||
979 | switch (type) { | |
980 | case STATUSTYPE_INFO: | |
981 | result[0] = '\0'; | |
982 | break; | |
983 | ||
984 | case STATUSTYPE_TABLE: | |
1da177e4 | 985 | if (cc->iv_mode) |
37af6560 CS |
986 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
987 | cc->iv_mode); | |
1da177e4 | 988 | else |
37af6560 | 989 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
990 | |
991 | if (cc->key_size > 0) { | |
992 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
993 | return -ENOMEM; | |
994 | ||
995 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
996 | sz += cc->key_size << 1; | |
997 | } else { | |
998 | if (sz >= maxlen) | |
999 | return -ENOMEM; | |
1000 | result[sz++] = '-'; | |
1001 | } | |
1002 | ||
4ee218cd AM |
1003 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1004 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1005 | break; |
1006 | } | |
1007 | return 0; | |
1008 | } | |
1009 | ||
e48d4bbf MB |
1010 | static void crypt_postsuspend(struct dm_target *ti) |
1011 | { | |
1012 | struct crypt_config *cc = ti->private; | |
1013 | ||
1014 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1015 | } | |
1016 | ||
1017 | static int crypt_preresume(struct dm_target *ti) | |
1018 | { | |
1019 | struct crypt_config *cc = ti->private; | |
1020 | ||
1021 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1022 | DMERR("aborting resume - crypt key is not set."); | |
1023 | return -EAGAIN; | |
1024 | } | |
1025 | ||
1026 | return 0; | |
1027 | } | |
1028 | ||
1029 | static void crypt_resume(struct dm_target *ti) | |
1030 | { | |
1031 | struct crypt_config *cc = ti->private; | |
1032 | ||
1033 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1034 | } | |
1035 | ||
1036 | /* Message interface | |
1037 | * key set <key> | |
1038 | * key wipe | |
1039 | */ | |
1040 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1041 | { | |
1042 | struct crypt_config *cc = ti->private; | |
1043 | ||
1044 | if (argc < 2) | |
1045 | goto error; | |
1046 | ||
1047 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1048 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1049 | DMWARN("not suspended during key manipulation."); | |
1050 | return -EINVAL; | |
1051 | } | |
1052 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1053 | return crypt_set_key(cc, argv[2]); | |
1054 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1055 | return crypt_wipe_key(cc); | |
1056 | } | |
1057 | ||
1058 | error: | |
1059 | DMWARN("unrecognised message received."); | |
1060 | return -EINVAL; | |
1061 | } | |
1062 | ||
1da177e4 LT |
1063 | static struct target_type crypt_target = { |
1064 | .name = "crypt", | |
46b47730 | 1065 | .version= {1, 5, 0}, |
1da177e4 LT |
1066 | .module = THIS_MODULE, |
1067 | .ctr = crypt_ctr, | |
1068 | .dtr = crypt_dtr, | |
1069 | .map = crypt_map, | |
1070 | .status = crypt_status, | |
e48d4bbf MB |
1071 | .postsuspend = crypt_postsuspend, |
1072 | .preresume = crypt_preresume, | |
1073 | .resume = crypt_resume, | |
1074 | .message = crypt_message, | |
1da177e4 LT |
1075 | }; |
1076 | ||
1077 | static int __init dm_crypt_init(void) | |
1078 | { | |
1079 | int r; | |
1080 | ||
028867ac | 1081 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1082 | if (!_crypt_io_pool) |
1083 | return -ENOMEM; | |
1084 | ||
1da177e4 LT |
1085 | r = dm_register_target(&crypt_target); |
1086 | if (r < 0) { | |
72d94861 | 1087 | DMERR("register failed %d", r); |
9934a8be | 1088 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1089 | } |
1090 | ||
1da177e4 LT |
1091 | return r; |
1092 | } | |
1093 | ||
1094 | static void __exit dm_crypt_exit(void) | |
1095 | { | |
1096 | int r = dm_unregister_target(&crypt_target); | |
1097 | ||
1098 | if (r < 0) | |
72d94861 | 1099 | DMERR("unregister failed %d", r); |
1da177e4 | 1100 | |
1da177e4 LT |
1101 | kmem_cache_destroy(_crypt_io_pool); |
1102 | } | |
1103 | ||
1104 | module_init(dm_crypt_init); | |
1105 | module_exit(dm_crypt_exit); | |
1106 | ||
1107 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1108 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1109 | MODULE_LICENSE("GPL"); |