blob: 49da55c1528aa01137a61c98d6033c9b84dc2e05 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C) 2003 Christophe Saout <christophe@saout.de>
3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
Milan Broz542da312009-12-10 23:51:57 +00004 * Copyright (C) 2006-2009 Red Hat, Inc. All rights reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 *
6 * This file is released under the GPL.
7 */
8
Milan Broz43d69032008-02-08 02:11:09 +00009#include <linux/completion.h>
Herbert Xud1806f62006-08-22 20:29:17 +100010#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/module.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
14#include <linux/bio.h>
15#include <linux/blkdev.h>
16#include <linux/mempool.h>
17#include <linux/slab.h>
18#include <linux/crypto.h>
19#include <linux/workqueue.h>
Andrew Morton3fcfab12006-10-19 23:28:16 -070020#include <linux/backing-dev.h>
Andi Kleenc0297722011-01-13 19:59:53 +000021#include <linux/percpu.h>
Arun Sharma600634972011-07-26 16:09:06 -070022#include <linux/atomic.h>
David Hardeman378f0582005-09-17 17:55:31 +100023#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <asm/page.h>
Rik Snel48527fa2006-09-03 08:56:39 +100025#include <asm/unaligned.h>
Milan Broz34745782011-01-13 19:59:55 +000026#include <crypto/hash.h>
27#include <crypto/md5.h>
28#include <crypto/algapi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
Mikulas Patocka586e80e2008-10-21 17:44:59 +010030#include <linux/device-mapper.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
Alasdair G Kergon72d94862006-06-26 00:27:35 -070032#define DM_MSG_PREFIX "crypt"
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
34/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 * context holding the current state of a multi-part conversion
36 */
37struct convert_context {
Milan Broz43d69032008-02-08 02:11:09 +000038 struct completion restart;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039 struct bio *bio_in;
40 struct bio *bio_out;
41 unsigned int offset_in;
42 unsigned int offset_out;
43 unsigned int idx_in;
44 unsigned int idx_out;
45 sector_t sector;
Milan Broz43d69032008-02-08 02:11:09 +000046 atomic_t pending;
Linus Torvalds1da177e2005-04-16 15:20:36 -070047};
48
Milan Broz53017032008-02-08 02:10:38 +000049/*
50 * per bio private data
51 */
52struct dm_crypt_io {
53 struct dm_target *target;
54 struct bio *base_bio;
55 struct work_struct work;
56
57 struct convert_context ctx;
58
59 atomic_t pending;
60 int error;
Milan Broz0c395b02008-02-08 02:10:54 +000061 sector_t sector;
Milan Broz393b47e2008-10-21 17:45:02 +010062 struct dm_crypt_io *base_io;
Milan Broz53017032008-02-08 02:10:38 +000063};
64
Milan Broz01482b72008-02-08 02:11:04 +000065struct dm_crypt_request {
Huang Yingb2174ee2009-03-16 17:44:33 +000066 struct convert_context *ctx;
Milan Broz01482b72008-02-08 02:11:04 +000067 struct scatterlist sg_in;
68 struct scatterlist sg_out;
Milan Broz2dc53272011-01-13 19:59:54 +000069 sector_t iv_sector;
Milan Broz01482b72008-02-08 02:11:04 +000070};
71
Linus Torvalds1da177e2005-04-16 15:20:36 -070072struct crypt_config;
73
74struct crypt_iv_operations {
75 int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
Milan Brozd469f842007-10-19 22:42:37 +010076 const char *opts);
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 void (*dtr)(struct crypt_config *cc);
Milan Brozb95bf2d2009-12-10 23:51:56 +000078 int (*init)(struct crypt_config *cc);
Milan Broz542da312009-12-10 23:51:57 +000079 int (*wipe)(struct crypt_config *cc);
Milan Broz2dc53272011-01-13 19:59:54 +000080 int (*generator)(struct crypt_config *cc, u8 *iv,
81 struct dm_crypt_request *dmreq);
82 int (*post)(struct crypt_config *cc, u8 *iv,
83 struct dm_crypt_request *dmreq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070084};
85
Milan Broz60473592009-12-10 23:51:55 +000086struct iv_essiv_private {
Milan Brozb95bf2d2009-12-10 23:51:56 +000087 struct crypto_hash *hash_tfm;
88 u8 *salt;
Milan Broz60473592009-12-10 23:51:55 +000089};
90
91struct iv_benbi_private {
92 int shift;
93};
94
Milan Broz34745782011-01-13 19:59:55 +000095#define LMK_SEED_SIZE 64 /* hash + 0 */
96struct iv_lmk_private {
97 struct crypto_shash *hash_tfm;
98 u8 *seed;
99};
100
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101/*
102 * Crypt: maps a linear range of a block device
103 * and encrypts / decrypts at the same time.
104 */
Milan Broze48d4bb2006-10-03 01:15:37 -0700105enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
Andi Kleenc0297722011-01-13 19:59:53 +0000106
107/*
108 * Duplicated per-CPU state for cipher.
109 */
110struct crypt_cpu {
111 struct ablkcipher_request *req;
Andi Kleenc0297722011-01-13 19:59:53 +0000112 /* ESSIV: struct crypto_cipher *essiv_tfm */
113 void *iv_private;
Milan Brozd1f96422011-01-13 19:59:54 +0000114 struct crypto_ablkcipher *tfms[0];
Andi Kleenc0297722011-01-13 19:59:53 +0000115};
116
117/*
118 * The fields in here must be read only after initialization,
119 * changing state should be in crypt_cpu.
120 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121struct crypt_config {
122 struct dm_dev *dev;
123 sector_t start;
124
125 /*
Milan Brozddd42ed2008-02-08 02:11:07 +0000126 * pool for per bio private data, crypto requests and
127 * encryption requeusts/buffer pages
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 */
129 mempool_t *io_pool;
Milan Brozddd42ed2008-02-08 02:11:07 +0000130 mempool_t *req_pool;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 mempool_t *page_pool;
Milan Broz6a24c712006-10-03 01:15:40 -0700132 struct bio_set *bs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133
Milan Brozcabf08e2007-10-19 22:38:58 +0100134 struct workqueue_struct *io_queue;
135 struct workqueue_struct *crypt_queue;
Milan Broz3f1e9072008-03-28 14:16:07 -0700136
Milan Broz5ebaee62010-08-12 04:14:07 +0100137 char *cipher;
Milan Broz7dbcd132011-01-13 19:59:52 +0000138 char *cipher_string;
Milan Broz5ebaee62010-08-12 04:14:07 +0100139
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 struct crypt_iv_operations *iv_gen_ops;
Herbert Xu79066ad2006-12-05 13:41:52 -0800141 union {
Milan Broz60473592009-12-10 23:51:55 +0000142 struct iv_essiv_private essiv;
143 struct iv_benbi_private benbi;
Milan Broz34745782011-01-13 19:59:55 +0000144 struct iv_lmk_private lmk;
Herbert Xu79066ad2006-12-05 13:41:52 -0800145 } iv_gen_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 sector_t iv_offset;
147 unsigned int iv_size;
148
Milan Brozddd42ed2008-02-08 02:11:07 +0000149 /*
Andi Kleenc0297722011-01-13 19:59:53 +0000150 * Duplicated per cpu state. Access through
151 * per_cpu_ptr() only.
152 */
153 struct crypt_cpu __percpu *cpu;
Milan Brozd1f96422011-01-13 19:59:54 +0000154 unsigned tfms_count;
Andi Kleenc0297722011-01-13 19:59:53 +0000155
156 /*
Milan Brozddd42ed2008-02-08 02:11:07 +0000157 * Layout of each crypto request:
158 *
159 * struct ablkcipher_request
160 * context
161 * padding
162 * struct dm_crypt_request
163 * padding
164 * IV
165 *
166 * The padding is added so that dm_crypt_request and the IV are
167 * correctly aligned.
168 */
169 unsigned int dmreq_start;
Milan Brozddd42ed2008-02-08 02:11:07 +0000170
Milan Broze48d4bb2006-10-03 01:15:37 -0700171 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 unsigned int key_size;
Milan Brozd1f96422011-01-13 19:59:54 +0000173 unsigned int key_parts;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 u8 key[0];
175};
176
Milan Broz6a24c712006-10-03 01:15:40 -0700177#define MIN_IOS 16
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178#define MIN_POOL_PAGES 32
179#define MIN_BIO_PAGES 8
180
Christoph Lametere18b8902006-12-06 20:33:20 -0800181static struct kmem_cache *_crypt_io_pool;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100183static void clone_init(struct dm_crypt_io *, struct bio *);
Alasdair G Kergon395b1672008-02-08 02:10:52 +0000184static void kcryptd_queue_crypt(struct dm_crypt_io *io);
Milan Broz2dc53272011-01-13 19:59:54 +0000185static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq);
Olaf Kirch027581f2007-05-09 02:32:52 -0700186
Andi Kleenc0297722011-01-13 19:59:53 +0000187static struct crypt_cpu *this_crypt_config(struct crypt_config *cc)
188{
189 return this_cpu_ptr(cc->cpu);
190}
191
192/*
193 * Use this to access cipher attributes that are the same for each CPU.
194 */
195static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
196{
Milan Brozd1f96422011-01-13 19:59:54 +0000197 return __this_cpu_ptr(cc->cpu)->tfms[0];
Andi Kleenc0297722011-01-13 19:59:53 +0000198}
199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 * Different IV generation algorithms:
202 *
Rik Snel3c164bd2006-09-02 18:17:33 +1000203 * plain: the initial vector is the 32-bit little-endian version of the sector
Robert P. J. Day3a4fa0a2007-10-19 23:10:43 +0200204 * number, padded with zeros if necessary.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 *
Milan Broz61afef62009-12-10 23:52:25 +0000206 * plain64: the initial vector is the 64-bit little-endian version of the sector
207 * number, padded with zeros if necessary.
208 *
Rik Snel3c164bd2006-09-02 18:17:33 +1000209 * essiv: "encrypted sector|salt initial vector", the sector number is
210 * encrypted with the bulk cipher using a salt as key. The salt
211 * should be derived from the bulk cipher's key via hashing.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 *
Rik Snel48527fa2006-09-03 08:56:39 +1000213 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
214 * (needed for LRW-32-AES and possible other narrow block modes)
215 *
Ludwig Nussel46b47732007-05-09 02:32:55 -0700216 * null: the initial vector is always zero. Provides compatibility with
217 * obsolete loop_fish2 devices. Do not use for new devices.
218 *
Milan Broz34745782011-01-13 19:59:55 +0000219 * lmk: Compatible implementation of the block chaining mode used
220 * by the Loop-AES block device encryption system
221 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
222 * It operates on full 512 byte sectors and uses CBC
223 * with an IV derived from the sector number, the data and
224 * optionally extra IV seed.
225 * This means that after decryption the first block
226 * of sector must be tweaked according to decrypted data.
227 * Loop-AES can use three encryption schemes:
228 * version 1: is plain aes-cbc mode
229 * version 2: uses 64 multikey scheme with lmk IV generator
230 * version 3: the same as version 2 with additional IV seed
231 * (it uses 65 keys, last key is used as IV seed)
232 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 * plumb: unimplemented, see:
234 * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
235 */
236
Milan Broz2dc53272011-01-13 19:59:54 +0000237static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
238 struct dm_crypt_request *dmreq)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239{
240 memset(iv, 0, cc->iv_size);
Alasdair G Kergon283a8322011-08-02 12:32:01 +0100241 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242
243 return 0;
244}
245
Milan Broz61afef62009-12-10 23:52:25 +0000246static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
Milan Broz2dc53272011-01-13 19:59:54 +0000247 struct dm_crypt_request *dmreq)
Milan Broz61afef62009-12-10 23:52:25 +0000248{
249 memset(iv, 0, cc->iv_size);
Alasdair G Kergon283a8322011-08-02 12:32:01 +0100250 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
Milan Broz61afef62009-12-10 23:52:25 +0000251
252 return 0;
253}
254
Milan Brozb95bf2d2009-12-10 23:51:56 +0000255/* Initialise ESSIV - compute salt but no local memory allocations */
256static int crypt_iv_essiv_init(struct crypt_config *cc)
257{
258 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
259 struct hash_desc desc;
260 struct scatterlist sg;
Andi Kleenc0297722011-01-13 19:59:53 +0000261 struct crypto_cipher *essiv_tfm;
262 int err, cpu;
Milan Brozb95bf2d2009-12-10 23:51:56 +0000263
264 sg_init_one(&sg, cc->key, cc->key_size);
265 desc.tfm = essiv->hash_tfm;
266 desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
267
268 err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt);
269 if (err)
270 return err;
271
Andi Kleenc0297722011-01-13 19:59:53 +0000272 for_each_possible_cpu(cpu) {
273 essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private,
274
275 err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
Milan Brozb95bf2d2009-12-10 23:51:56 +0000276 crypto_hash_digestsize(essiv->hash_tfm));
Andi Kleenc0297722011-01-13 19:59:53 +0000277 if (err)
278 return err;
279 }
280
281 return 0;
Milan Brozb95bf2d2009-12-10 23:51:56 +0000282}
283
Milan Broz542da312009-12-10 23:51:57 +0000284/* Wipe salt and reset key derived from volume key */
285static int crypt_iv_essiv_wipe(struct crypt_config *cc)
286{
287 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
288 unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
Andi Kleenc0297722011-01-13 19:59:53 +0000289 struct crypto_cipher *essiv_tfm;
290 int cpu, r, err = 0;
Milan Broz542da312009-12-10 23:51:57 +0000291
292 memset(essiv->salt, 0, salt_size);
293
Andi Kleenc0297722011-01-13 19:59:53 +0000294 for_each_possible_cpu(cpu) {
295 essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private;
296 r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
297 if (r)
298 err = r;
299 }
300
301 return err;
302}
303
304/* Set up per cpu cipher state */
305static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
306 struct dm_target *ti,
307 u8 *salt, unsigned saltsize)
308{
309 struct crypto_cipher *essiv_tfm;
310 int err;
311
312 /* Setup the essiv_tfm with the given salt */
313 essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
314 if (IS_ERR(essiv_tfm)) {
315 ti->error = "Error allocating crypto tfm for ESSIV";
316 return essiv_tfm;
317 }
318
319 if (crypto_cipher_blocksize(essiv_tfm) !=
320 crypto_ablkcipher_ivsize(any_tfm(cc))) {
321 ti->error = "Block size of ESSIV cipher does "
322 "not match IV size of block cipher";
323 crypto_free_cipher(essiv_tfm);
324 return ERR_PTR(-EINVAL);
325 }
326
327 err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
328 if (err) {
329 ti->error = "Failed to set key for ESSIV cipher";
330 crypto_free_cipher(essiv_tfm);
331 return ERR_PTR(err);
332 }
333
334 return essiv_tfm;
Milan Broz542da312009-12-10 23:51:57 +0000335}
336
Milan Broz60473592009-12-10 23:51:55 +0000337static void crypt_iv_essiv_dtr(struct crypt_config *cc)
338{
Andi Kleenc0297722011-01-13 19:59:53 +0000339 int cpu;
340 struct crypt_cpu *cpu_cc;
341 struct crypto_cipher *essiv_tfm;
Milan Broz60473592009-12-10 23:51:55 +0000342 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
343
Milan Brozb95bf2d2009-12-10 23:51:56 +0000344 crypto_free_hash(essiv->hash_tfm);
345 essiv->hash_tfm = NULL;
346
347 kzfree(essiv->salt);
348 essiv->salt = NULL;
Andi Kleenc0297722011-01-13 19:59:53 +0000349
350 for_each_possible_cpu(cpu) {
351 cpu_cc = per_cpu_ptr(cc->cpu, cpu);
352 essiv_tfm = cpu_cc->iv_private;
353
354 if (essiv_tfm)
355 crypto_free_cipher(essiv_tfm);
356
357 cpu_cc->iv_private = NULL;
358 }
Milan Broz60473592009-12-10 23:51:55 +0000359}
360
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
Milan Brozd469f842007-10-19 22:42:37 +0100362 const char *opts)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363{
Milan Broz5861f1b2009-12-10 23:51:56 +0000364 struct crypto_cipher *essiv_tfm = NULL;
365 struct crypto_hash *hash_tfm = NULL;
Milan Broz5861f1b2009-12-10 23:51:56 +0000366 u8 *salt = NULL;
Andi Kleenc0297722011-01-13 19:59:53 +0000367 int err, cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
Milan Broz5861f1b2009-12-10 23:51:56 +0000369 if (!opts) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700370 ti->error = "Digest algorithm missing for ESSIV mode";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 return -EINVAL;
372 }
373
Milan Brozb95bf2d2009-12-10 23:51:56 +0000374 /* Allocate hash algorithm */
Herbert Xu35058682006-08-24 19:10:20 +1000375 hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC);
376 if (IS_ERR(hash_tfm)) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700377 ti->error = "Error initializing ESSIV hash";
Milan Broz5861f1b2009-12-10 23:51:56 +0000378 err = PTR_ERR(hash_tfm);
379 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 }
381
Milan Brozb95bf2d2009-12-10 23:51:56 +0000382 salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL);
Milan Broz5861f1b2009-12-10 23:51:56 +0000383 if (!salt) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700384 ti->error = "Error kmallocing salt storage in ESSIV";
Milan Broz5861f1b2009-12-10 23:51:56 +0000385 err = -ENOMEM;
386 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 }
388
Milan Brozb95bf2d2009-12-10 23:51:56 +0000389 cc->iv_gen_private.essiv.salt = salt;
Milan Brozb95bf2d2009-12-10 23:51:56 +0000390 cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
391
Andi Kleenc0297722011-01-13 19:59:53 +0000392 for_each_possible_cpu(cpu) {
393 essiv_tfm = setup_essiv_cpu(cc, ti, salt,
394 crypto_hash_digestsize(hash_tfm));
395 if (IS_ERR(essiv_tfm)) {
396 crypt_iv_essiv_dtr(cc);
397 return PTR_ERR(essiv_tfm);
398 }
399 per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm;
400 }
401
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 return 0;
Milan Broz5861f1b2009-12-10 23:51:56 +0000403
404bad:
Milan Broz5861f1b2009-12-10 23:51:56 +0000405 if (hash_tfm && !IS_ERR(hash_tfm))
406 crypto_free_hash(hash_tfm);
Milan Brozb95bf2d2009-12-10 23:51:56 +0000407 kfree(salt);
Milan Broz5861f1b2009-12-10 23:51:56 +0000408 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409}
410
Milan Broz2dc53272011-01-13 19:59:54 +0000411static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
412 struct dm_crypt_request *dmreq)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413{
Andi Kleenc0297722011-01-13 19:59:53 +0000414 struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private;
415
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 memset(iv, 0, cc->iv_size);
Alasdair G Kergon283a8322011-08-02 12:32:01 +0100417 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
Andi Kleenc0297722011-01-13 19:59:53 +0000418 crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
419
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 return 0;
421}
422
Rik Snel48527fa2006-09-03 08:56:39 +1000423static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
424 const char *opts)
425{
Andi Kleenc0297722011-01-13 19:59:53 +0000426 unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
David Howellsf0d1b0b2006-12-08 02:37:49 -0800427 int log = ilog2(bs);
Rik Snel48527fa2006-09-03 08:56:39 +1000428
429 /* we need to calculate how far we must shift the sector count
430 * to get the cipher block count, we use this shift in _gen */
431
432 if (1 << log != bs) {
433 ti->error = "cypher blocksize is not a power of 2";
434 return -EINVAL;
435 }
436
437 if (log > 9) {
438 ti->error = "cypher blocksize is > 512";
439 return -EINVAL;
440 }
441
Milan Broz60473592009-12-10 23:51:55 +0000442 cc->iv_gen_private.benbi.shift = 9 - log;
Rik Snel48527fa2006-09-03 08:56:39 +1000443
444 return 0;
445}
446
447static void crypt_iv_benbi_dtr(struct crypt_config *cc)
448{
Rik Snel48527fa2006-09-03 08:56:39 +1000449}
450
Milan Broz2dc53272011-01-13 19:59:54 +0000451static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
452 struct dm_crypt_request *dmreq)
Rik Snel48527fa2006-09-03 08:56:39 +1000453{
Herbert Xu79066ad2006-12-05 13:41:52 -0800454 __be64 val;
455
Rik Snel48527fa2006-09-03 08:56:39 +1000456 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
Herbert Xu79066ad2006-12-05 13:41:52 -0800457
Milan Broz2dc53272011-01-13 19:59:54 +0000458 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
Herbert Xu79066ad2006-12-05 13:41:52 -0800459 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
Rik Snel48527fa2006-09-03 08:56:39 +1000460
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 return 0;
462}
463
Milan Broz2dc53272011-01-13 19:59:54 +0000464static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
465 struct dm_crypt_request *dmreq)
Ludwig Nussel46b47732007-05-09 02:32:55 -0700466{
467 memset(iv, 0, cc->iv_size);
468
469 return 0;
470}
471
Milan Broz34745782011-01-13 19:59:55 +0000472static void crypt_iv_lmk_dtr(struct crypt_config *cc)
473{
474 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
475
476 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
477 crypto_free_shash(lmk->hash_tfm);
478 lmk->hash_tfm = NULL;
479
480 kzfree(lmk->seed);
481 lmk->seed = NULL;
482}
483
484static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
485 const char *opts)
486{
487 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
488
489 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
490 if (IS_ERR(lmk->hash_tfm)) {
491 ti->error = "Error initializing LMK hash";
492 return PTR_ERR(lmk->hash_tfm);
493 }
494
495 /* No seed in LMK version 2 */
496 if (cc->key_parts == cc->tfms_count) {
497 lmk->seed = NULL;
498 return 0;
499 }
500
501 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
502 if (!lmk->seed) {
503 crypt_iv_lmk_dtr(cc);
504 ti->error = "Error kmallocing seed storage in LMK";
505 return -ENOMEM;
506 }
507
508 return 0;
509}
510
511static int crypt_iv_lmk_init(struct crypt_config *cc)
512{
513 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
514 int subkey_size = cc->key_size / cc->key_parts;
515
516 /* LMK seed is on the position of LMK_KEYS + 1 key */
517 if (lmk->seed)
518 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
519 crypto_shash_digestsize(lmk->hash_tfm));
520
521 return 0;
522}
523
524static int crypt_iv_lmk_wipe(struct crypt_config *cc)
525{
526 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
527
528 if (lmk->seed)
529 memset(lmk->seed, 0, LMK_SEED_SIZE);
530
531 return 0;
532}
533
534static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
535 struct dm_crypt_request *dmreq,
536 u8 *data)
537{
538 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
539 struct {
540 struct shash_desc desc;
541 char ctx[crypto_shash_descsize(lmk->hash_tfm)];
542 } sdesc;
543 struct md5_state md5state;
544 u32 buf[4];
545 int i, r;
546
547 sdesc.desc.tfm = lmk->hash_tfm;
548 sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
549
550 r = crypto_shash_init(&sdesc.desc);
551 if (r)
552 return r;
553
554 if (lmk->seed) {
555 r = crypto_shash_update(&sdesc.desc, lmk->seed, LMK_SEED_SIZE);
556 if (r)
557 return r;
558 }
559
560 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
561 r = crypto_shash_update(&sdesc.desc, data + 16, 16 * 31);
562 if (r)
563 return r;
564
565 /* Sector is cropped to 56 bits here */
566 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
567 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
568 buf[2] = cpu_to_le32(4024);
569 buf[3] = 0;
570 r = crypto_shash_update(&sdesc.desc, (u8 *)buf, sizeof(buf));
571 if (r)
572 return r;
573
574 /* No MD5 padding here */
575 r = crypto_shash_export(&sdesc.desc, &md5state);
576 if (r)
577 return r;
578
579 for (i = 0; i < MD5_HASH_WORDS; i++)
580 __cpu_to_le32s(&md5state.hash[i]);
581 memcpy(iv, &md5state.hash, cc->iv_size);
582
583 return 0;
584}
585
586static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
587 struct dm_crypt_request *dmreq)
588{
589 u8 *src;
590 int r = 0;
591
592 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
593 src = kmap_atomic(sg_page(&dmreq->sg_in), KM_USER0);
594 r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset);
595 kunmap_atomic(src, KM_USER0);
596 } else
597 memset(iv, 0, cc->iv_size);
598
599 return r;
600}
601
602static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
603 struct dm_crypt_request *dmreq)
604{
605 u8 *dst;
606 int r;
607
608 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
609 return 0;
610
611 dst = kmap_atomic(sg_page(&dmreq->sg_out), KM_USER0);
612 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + dmreq->sg_out.offset);
613
614 /* Tweak the first block of plaintext sector */
615 if (!r)
616 crypto_xor(dst + dmreq->sg_out.offset, iv, cc->iv_size);
617
618 kunmap_atomic(dst, KM_USER0);
619 return r;
620}
621
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622static struct crypt_iv_operations crypt_iv_plain_ops = {
623 .generator = crypt_iv_plain_gen
624};
625
Milan Broz61afef62009-12-10 23:52:25 +0000626static struct crypt_iv_operations crypt_iv_plain64_ops = {
627 .generator = crypt_iv_plain64_gen
628};
629
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630static struct crypt_iv_operations crypt_iv_essiv_ops = {
631 .ctr = crypt_iv_essiv_ctr,
632 .dtr = crypt_iv_essiv_dtr,
Milan Brozb95bf2d2009-12-10 23:51:56 +0000633 .init = crypt_iv_essiv_init,
Milan Broz542da312009-12-10 23:51:57 +0000634 .wipe = crypt_iv_essiv_wipe,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 .generator = crypt_iv_essiv_gen
636};
637
Rik Snel48527fa2006-09-03 08:56:39 +1000638static struct crypt_iv_operations crypt_iv_benbi_ops = {
639 .ctr = crypt_iv_benbi_ctr,
640 .dtr = crypt_iv_benbi_dtr,
641 .generator = crypt_iv_benbi_gen
642};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643
Ludwig Nussel46b47732007-05-09 02:32:55 -0700644static struct crypt_iv_operations crypt_iv_null_ops = {
645 .generator = crypt_iv_null_gen
646};
647
Milan Broz34745782011-01-13 19:59:55 +0000648static struct crypt_iv_operations crypt_iv_lmk_ops = {
649 .ctr = crypt_iv_lmk_ctr,
650 .dtr = crypt_iv_lmk_dtr,
651 .init = crypt_iv_lmk_init,
652 .wipe = crypt_iv_lmk_wipe,
653 .generator = crypt_iv_lmk_gen,
654 .post = crypt_iv_lmk_post
655};
656
Milan Brozd469f842007-10-19 22:42:37 +0100657static void crypt_convert_init(struct crypt_config *cc,
658 struct convert_context *ctx,
659 struct bio *bio_out, struct bio *bio_in,
Milan Brozfcd369d2008-02-08 02:10:41 +0000660 sector_t sector)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661{
662 ctx->bio_in = bio_in;
663 ctx->bio_out = bio_out;
664 ctx->offset_in = 0;
665 ctx->offset_out = 0;
666 ctx->idx_in = bio_in ? bio_in->bi_idx : 0;
667 ctx->idx_out = bio_out ? bio_out->bi_idx : 0;
668 ctx->sector = sector + cc->iv_offset;
Milan Broz43d69032008-02-08 02:11:09 +0000669 init_completion(&ctx->restart);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670}
671
Huang Yingb2174ee2009-03-16 17:44:33 +0000672static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
673 struct ablkcipher_request *req)
674{
675 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
676}
677
678static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
679 struct dm_crypt_request *dmreq)
680{
681 return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
682}
683
Milan Broz2dc53272011-01-13 19:59:54 +0000684static u8 *iv_of_dmreq(struct crypt_config *cc,
685 struct dm_crypt_request *dmreq)
686{
687 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
688 crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
689}
690
Milan Broz01482b72008-02-08 02:11:04 +0000691static int crypt_convert_block(struct crypt_config *cc,
Milan Broz3a7f6c92008-02-08 02:11:14 +0000692 struct convert_context *ctx,
693 struct ablkcipher_request *req)
Milan Broz01482b72008-02-08 02:11:04 +0000694{
695 struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in);
696 struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000697 struct dm_crypt_request *dmreq;
698 u8 *iv;
699 int r = 0;
Milan Broz01482b72008-02-08 02:11:04 +0000700
Huang Yingb2174ee2009-03-16 17:44:33 +0000701 dmreq = dmreq_of_req(cc, req);
Milan Broz2dc53272011-01-13 19:59:54 +0000702 iv = iv_of_dmreq(cc, dmreq);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000703
Milan Broz2dc53272011-01-13 19:59:54 +0000704 dmreq->iv_sector = ctx->sector;
Huang Yingb2174ee2009-03-16 17:44:33 +0000705 dmreq->ctx = ctx;
Milan Broz3a7f6c92008-02-08 02:11:14 +0000706 sg_init_table(&dmreq->sg_in, 1);
707 sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
Milan Broz01482b72008-02-08 02:11:04 +0000708 bv_in->bv_offset + ctx->offset_in);
709
Milan Broz3a7f6c92008-02-08 02:11:14 +0000710 sg_init_table(&dmreq->sg_out, 1);
711 sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT,
Milan Broz01482b72008-02-08 02:11:04 +0000712 bv_out->bv_offset + ctx->offset_out);
713
714 ctx->offset_in += 1 << SECTOR_SHIFT;
715 if (ctx->offset_in >= bv_in->bv_len) {
716 ctx->offset_in = 0;
717 ctx->idx_in++;
718 }
719
720 ctx->offset_out += 1 << SECTOR_SHIFT;
721 if (ctx->offset_out >= bv_out->bv_len) {
722 ctx->offset_out = 0;
723 ctx->idx_out++;
724 }
725
Milan Broz3a7f6c92008-02-08 02:11:14 +0000726 if (cc->iv_gen_ops) {
Milan Broz2dc53272011-01-13 19:59:54 +0000727 r = cc->iv_gen_ops->generator(cc, iv, dmreq);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000728 if (r < 0)
729 return r;
730 }
731
732 ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
733 1 << SECTOR_SHIFT, iv);
734
735 if (bio_data_dir(ctx->bio_in) == WRITE)
736 r = crypto_ablkcipher_encrypt(req);
737 else
738 r = crypto_ablkcipher_decrypt(req);
739
Milan Broz2dc53272011-01-13 19:59:54 +0000740 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
741 r = cc->iv_gen_ops->post(cc, iv, dmreq);
742
Milan Broz3a7f6c92008-02-08 02:11:14 +0000743 return r;
Milan Broz01482b72008-02-08 02:11:04 +0000744}
745
Milan Broz95497a92008-02-08 02:11:12 +0000746static void kcryptd_async_done(struct crypto_async_request *async_req,
747 int error);
Andi Kleenc0297722011-01-13 19:59:53 +0000748
Milan Brozddd42ed2008-02-08 02:11:07 +0000749static void crypt_alloc_req(struct crypt_config *cc,
750 struct convert_context *ctx)
751{
Andi Kleenc0297722011-01-13 19:59:53 +0000752 struct crypt_cpu *this_cc = this_crypt_config(cc);
Milan Brozd1f96422011-01-13 19:59:54 +0000753 unsigned key_index = ctx->sector & (cc->tfms_count - 1);
Andi Kleenc0297722011-01-13 19:59:53 +0000754
755 if (!this_cc->req)
756 this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
757
Milan Brozd1f96422011-01-13 19:59:54 +0000758 ablkcipher_request_set_tfm(this_cc->req, this_cc->tfms[key_index]);
Andi Kleenc0297722011-01-13 19:59:53 +0000759 ablkcipher_request_set_callback(this_cc->req,
760 CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
761 kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
Milan Brozddd42ed2008-02-08 02:11:07 +0000762}
763
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764/*
765 * Encrypt / decrypt data from one bio to another one (can be the same one)
766 */
767static int crypt_convert(struct crypt_config *cc,
Milan Brozd469f842007-10-19 22:42:37 +0100768 struct convert_context *ctx)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769{
Andi Kleenc0297722011-01-13 19:59:53 +0000770 struct crypt_cpu *this_cc = this_crypt_config(cc);
Milan Broz3f1e9072008-03-28 14:16:07 -0700771 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772
Milan Brozc8081612008-10-10 13:37:08 +0100773 atomic_set(&ctx->pending, 1);
774
Linus Torvalds1da177e2005-04-16 15:20:36 -0700775 while(ctx->idx_in < ctx->bio_in->bi_vcnt &&
776 ctx->idx_out < ctx->bio_out->bi_vcnt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777
Milan Broz3a7f6c92008-02-08 02:11:14 +0000778 crypt_alloc_req(cc, ctx);
779
Milan Broz3f1e9072008-03-28 14:16:07 -0700780 atomic_inc(&ctx->pending);
781
Andi Kleenc0297722011-01-13 19:59:53 +0000782 r = crypt_convert_block(cc, ctx, this_cc->req);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000783
784 switch (r) {
Milan Broz3f1e9072008-03-28 14:16:07 -0700785 /* async */
Milan Broz3a7f6c92008-02-08 02:11:14 +0000786 case -EBUSY:
787 wait_for_completion(&ctx->restart);
788 INIT_COMPLETION(ctx->restart);
789 /* fall through*/
790 case -EINPROGRESS:
Andi Kleenc0297722011-01-13 19:59:53 +0000791 this_cc->req = NULL;
Milan Broz3a7f6c92008-02-08 02:11:14 +0000792 ctx->sector++;
793 continue;
Milan Broz3a7f6c92008-02-08 02:11:14 +0000794
Milan Broz3f1e9072008-03-28 14:16:07 -0700795 /* sync */
796 case 0:
797 atomic_dec(&ctx->pending);
798 ctx->sector++;
Milan Brozc7f1b202008-07-02 09:34:28 +0100799 cond_resched();
Milan Broz3f1e9072008-03-28 14:16:07 -0700800 continue;
801
802 /* error */
803 default:
804 atomic_dec(&ctx->pending);
805 return r;
806 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807 }
808
Milan Broz3f1e9072008-03-28 14:16:07 -0700809 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810}
811
Milan Brozd469f842007-10-19 22:42:37 +0100812static void dm_crypt_bio_destructor(struct bio *bio)
813{
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100814 struct dm_crypt_io *io = bio->bi_private;
Milan Broz6a24c712006-10-03 01:15:40 -0700815 struct crypt_config *cc = io->target->private;
816
817 bio_free(bio, cc->bs);
Milan Brozd469f842007-10-19 22:42:37 +0100818}
Milan Broz6a24c712006-10-03 01:15:40 -0700819
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820/*
821 * Generate a new unfragmented bio with the given size
822 * This should never violate the device limitations
Milan Broz933f01d2008-10-10 13:37:08 +0100823 * May return a smaller bio when running out of pages, indicated by
824 * *out_of_pages set to 1.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 */
Milan Broz933f01d2008-10-10 13:37:08 +0100826static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size,
827 unsigned *out_of_pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828{
Olaf Kirch027581f2007-05-09 02:32:52 -0700829 struct crypt_config *cc = io->target->private;
Milan Broz8b004452006-10-03 01:15:37 -0700830 struct bio *clone;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
Al Virob4e3ca12005-10-21 03:22:34 -0400832 gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM;
Milan Broz91e10622007-12-13 14:16:10 +0000833 unsigned i, len;
834 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835
Olaf Kirch2f9941b2007-05-09 02:32:53 -0700836 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs);
Milan Broz8b004452006-10-03 01:15:37 -0700837 if (!clone)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839
Olaf Kirch027581f2007-05-09 02:32:52 -0700840 clone_init(io, clone);
Milan Broz933f01d2008-10-10 13:37:08 +0100841 *out_of_pages = 0;
Milan Broz6a24c712006-10-03 01:15:40 -0700842
Olaf Kirchf97380b2007-05-09 02:32:54 -0700843 for (i = 0; i < nr_iovecs; i++) {
Milan Broz91e10622007-12-13 14:16:10 +0000844 page = mempool_alloc(cc->page_pool, gfp_mask);
Milan Broz933f01d2008-10-10 13:37:08 +0100845 if (!page) {
846 *out_of_pages = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 break;
Milan Broz933f01d2008-10-10 13:37:08 +0100848 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849
850 /*
851 * if additional pages cannot be allocated without waiting,
852 * return a partially allocated bio, the caller will then try
853 * to allocate additional bios while submitting this partial bio
854 */
Olaf Kirchf97380b2007-05-09 02:32:54 -0700855 if (i == (MIN_BIO_PAGES - 1))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856 gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT;
857
Milan Broz91e10622007-12-13 14:16:10 +0000858 len = (size > PAGE_SIZE) ? PAGE_SIZE : size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859
Milan Broz91e10622007-12-13 14:16:10 +0000860 if (!bio_add_page(clone, page, len, 0)) {
861 mempool_free(page, cc->page_pool);
862 break;
863 }
864
865 size -= len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700866 }
867
Milan Broz8b004452006-10-03 01:15:37 -0700868 if (!clone->bi_size) {
869 bio_put(clone);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 return NULL;
871 }
872
Milan Broz8b004452006-10-03 01:15:37 -0700873 return clone;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874}
875
Neil Brown644bd2f2007-10-16 13:48:46 +0200876static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877{
Neil Brown644bd2f2007-10-16 13:48:46 +0200878 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 struct bio_vec *bv;
880
Neil Brown644bd2f2007-10-16 13:48:46 +0200881 for (i = 0; i < clone->bi_vcnt; i++) {
Milan Broz8b004452006-10-03 01:15:37 -0700882 bv = bio_iovec_idx(clone, i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883 BUG_ON(!bv->bv_page);
884 mempool_free(bv->bv_page, cc->page_pool);
885 bv->bv_page = NULL;
886 }
887}
888
Milan Brozdc440d1e2008-10-10 13:37:03 +0100889static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti,
890 struct bio *bio, sector_t sector)
891{
892 struct crypt_config *cc = ti->private;
893 struct dm_crypt_io *io;
894
895 io = mempool_alloc(cc->io_pool, GFP_NOIO);
896 io->target = ti;
897 io->base_bio = bio;
898 io->sector = sector;
899 io->error = 0;
Milan Broz393b47e2008-10-21 17:45:02 +0100900 io->base_io = NULL;
Milan Brozdc440d1e2008-10-10 13:37:03 +0100901 atomic_set(&io->pending, 0);
902
903 return io;
904}
905
Milan Broz3e1a8bd2008-10-10 13:37:02 +0100906static void crypt_inc_pending(struct dm_crypt_io *io)
907{
908 atomic_inc(&io->pending);
909}
910
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911/*
912 * One of the bios was finished. Check for completion of
913 * the whole request and correctly clean up the buffer.
Milan Broz393b47e2008-10-21 17:45:02 +0100914 * If base_io is set, wait for the last fragment to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 */
Milan Broz5742fd72008-02-08 02:10:43 +0000916static void crypt_dec_pending(struct dm_crypt_io *io)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917{
Milan Broz5742fd72008-02-08 02:10:43 +0000918 struct crypt_config *cc = io->target->private;
Milan Brozb35f8ca2009-03-16 17:44:36 +0000919 struct bio *base_bio = io->base_bio;
920 struct dm_crypt_io *base_io = io->base_io;
921 int error = io->error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922
923 if (!atomic_dec_and_test(&io->pending))
924 return;
925
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 mempool_free(io, cc->io_pool);
Milan Brozb35f8ca2009-03-16 17:44:36 +0000927
928 if (likely(!base_io))
929 bio_endio(base_bio, error);
930 else {
931 if (error && !base_io->error)
932 base_io->error = error;
933 crypt_dec_pending(base_io);
934 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935}
936
937/*
Milan Brozcabf08e2007-10-19 22:38:58 +0100938 * kcryptd/kcryptd_io:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939 *
940 * Needed because it would be very unwise to do decryption in an
Milan Broz23541d22006-10-03 01:15:39 -0700941 * interrupt context.
Milan Brozcabf08e2007-10-19 22:38:58 +0100942 *
943 * kcryptd performs the actual encryption or decryption.
944 *
945 * kcryptd_io performs the IO submission.
946 *
947 * They must be separated as otherwise the final stages could be
948 * starved by new requests which can block in the first stages due
949 * to memory allocation.
Andi Kleenc0297722011-01-13 19:59:53 +0000950 *
951 * The work is done per CPU global for all dm-crypt instances.
952 * They should not depend on each other and do not block.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700953 */
NeilBrown6712ecf2007-09-27 12:47:43 +0200954static void crypt_endio(struct bio *clone, int error)
Milan Broz8b004452006-10-03 01:15:37 -0700955{
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100956 struct dm_crypt_io *io = clone->bi_private;
Milan Broz8b004452006-10-03 01:15:37 -0700957 struct crypt_config *cc = io->target->private;
Milan Brozee7a4912008-02-08 02:10:46 +0000958 unsigned rw = bio_data_dir(clone);
Milan Broz8b004452006-10-03 01:15:37 -0700959
Milan Brozadfe4772007-12-13 14:15:51 +0000960 if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error))
961 error = -EIO;
962
Milan Broz8b004452006-10-03 01:15:37 -0700963 /*
NeilBrown6712ecf2007-09-27 12:47:43 +0200964 * free the processed pages
Milan Broz8b004452006-10-03 01:15:37 -0700965 */
Milan Brozee7a4912008-02-08 02:10:46 +0000966 if (rw == WRITE)
Neil Brown644bd2f2007-10-16 13:48:46 +0200967 crypt_free_buffer_pages(cc, clone);
Milan Brozee7a4912008-02-08 02:10:46 +0000968
969 bio_put(clone);
970
971 if (rw == READ && !error) {
972 kcryptd_queue_crypt(io);
973 return;
NeilBrown6712ecf2007-09-27 12:47:43 +0200974 }
Milan Broz8b004452006-10-03 01:15:37 -0700975
Milan Brozadfe4772007-12-13 14:15:51 +0000976 if (unlikely(error))
Milan Broz5742fd72008-02-08 02:10:43 +0000977 io->error = error;
978
979 crypt_dec_pending(io);
Milan Broz8b004452006-10-03 01:15:37 -0700980}
981
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100982static void clone_init(struct dm_crypt_io *io, struct bio *clone)
Milan Broz8b004452006-10-03 01:15:37 -0700983{
984 struct crypt_config *cc = io->target->private;
985
986 clone->bi_private = io;
987 clone->bi_end_io = crypt_endio;
988 clone->bi_bdev = cc->dev->bdev;
989 clone->bi_rw = io->base_bio->bi_rw;
Olaf Kirch027581f2007-05-09 02:32:52 -0700990 clone->bi_destructor = dm_crypt_bio_destructor;
Milan Broz8b004452006-10-03 01:15:37 -0700991}
992
Milan Broz20c82532011-01-13 19:59:53 +0000993static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
Milan Broz8b004452006-10-03 01:15:37 -0700994{
995 struct crypt_config *cc = io->target->private;
996 struct bio *base_bio = io->base_bio;
997 struct bio *clone;
Milan Broz93e605c2006-10-03 01:15:38 -0700998
Milan Broz8b004452006-10-03 01:15:37 -0700999 /*
1000 * The block layer might modify the bvec array, so always
1001 * copy the required bvecs because we need the original
1002 * one in order to decrypt the whole bio data *afterwards*.
1003 */
Milan Broz20c82532011-01-13 19:59:53 +00001004 clone = bio_alloc_bioset(gfp, bio_segments(base_bio), cc->bs);
Jens Axboe7eaceac2011-03-10 08:52:07 +01001005 if (!clone)
Milan Broz20c82532011-01-13 19:59:53 +00001006 return 1;
Milan Broz8b004452006-10-03 01:15:37 -07001007
Milan Broz20c82532011-01-13 19:59:53 +00001008 crypt_inc_pending(io);
1009
Milan Broz8b004452006-10-03 01:15:37 -07001010 clone_init(io, clone);
1011 clone->bi_idx = 0;
1012 clone->bi_vcnt = bio_segments(base_bio);
1013 clone->bi_size = base_bio->bi_size;
Milan Broz0c395b02008-02-08 02:10:54 +00001014 clone->bi_sector = cc->start + io->sector;
Milan Broz8b004452006-10-03 01:15:37 -07001015 memcpy(clone->bi_io_vec, bio_iovec(base_bio),
1016 sizeof(struct bio_vec) * clone->bi_vcnt);
Milan Broz8b004452006-10-03 01:15:37 -07001017
Milan Broz93e605c2006-10-03 01:15:38 -07001018 generic_make_request(clone);
Milan Broz20c82532011-01-13 19:59:53 +00001019 return 0;
Milan Broz8b004452006-10-03 01:15:37 -07001020}
1021
Milan Broz4e4eef62008-02-08 02:10:49 +00001022static void kcryptd_io_write(struct dm_crypt_io *io)
1023{
Milan Broz95497a92008-02-08 02:11:12 +00001024 struct bio *clone = io->ctx.bio_out;
Milan Broz95497a92008-02-08 02:11:12 +00001025 generic_make_request(clone);
Milan Broz4e4eef62008-02-08 02:10:49 +00001026}
1027
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001028static void kcryptd_io(struct work_struct *work)
1029{
1030 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1031
Milan Broz20c82532011-01-13 19:59:53 +00001032 if (bio_data_dir(io->base_bio) == READ) {
1033 crypt_inc_pending(io);
1034 if (kcryptd_io_read(io, GFP_NOIO))
1035 io->error = -ENOMEM;
1036 crypt_dec_pending(io);
1037 } else
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001038 kcryptd_io_write(io);
1039}
1040
1041static void kcryptd_queue_io(struct dm_crypt_io *io)
1042{
1043 struct crypt_config *cc = io->target->private;
1044
1045 INIT_WORK(&io->work, kcryptd_io);
1046 queue_work(cc->io_queue, &io->work);
1047}
1048
Milan Broz95497a92008-02-08 02:11:12 +00001049static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io,
1050 int error, int async)
Milan Broz4e4eef62008-02-08 02:10:49 +00001051{
Milan Brozdec1ced2008-02-08 02:10:57 +00001052 struct bio *clone = io->ctx.bio_out;
1053 struct crypt_config *cc = io->target->private;
1054
1055 if (unlikely(error < 0)) {
1056 crypt_free_buffer_pages(cc, clone);
1057 bio_put(clone);
1058 io->error = -EIO;
Milan Broz6c031f42008-10-10 13:37:06 +01001059 crypt_dec_pending(io);
Milan Brozdec1ced2008-02-08 02:10:57 +00001060 return;
1061 }
1062
1063 /* crypt_convert should have filled the clone bio */
1064 BUG_ON(io->ctx.idx_out < clone->bi_vcnt);
1065
1066 clone->bi_sector = cc->start + io->sector;
Milan Broz899c95d2008-02-08 02:11:02 +00001067
Milan Broz95497a92008-02-08 02:11:12 +00001068 if (async)
1069 kcryptd_queue_io(io);
Alasdair G Kergon1e37bb82008-10-10 13:37:05 +01001070 else
Milan Broz95497a92008-02-08 02:11:12 +00001071 generic_make_request(clone);
Milan Broz4e4eef62008-02-08 02:10:49 +00001072}
1073
Milan Brozfc5a5e92008-10-10 13:37:04 +01001074static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
Milan Broz8b004452006-10-03 01:15:37 -07001075{
1076 struct crypt_config *cc = io->target->private;
Milan Broz8b004452006-10-03 01:15:37 -07001077 struct bio *clone;
Milan Broz393b47e2008-10-21 17:45:02 +01001078 struct dm_crypt_io *new_io;
Milan Brozc8081612008-10-10 13:37:08 +01001079 int crypt_finished;
Milan Broz933f01d2008-10-10 13:37:08 +01001080 unsigned out_of_pages = 0;
Milan Brozdec1ced2008-02-08 02:10:57 +00001081 unsigned remaining = io->base_bio->bi_size;
Milan Brozb635b002008-10-21 17:45:00 +01001082 sector_t sector = io->sector;
Milan Brozdec1ced2008-02-08 02:10:57 +00001083 int r;
Milan Broz8b004452006-10-03 01:15:37 -07001084
Milan Broz93e605c2006-10-03 01:15:38 -07001085 /*
Milan Brozfc5a5e92008-10-10 13:37:04 +01001086 * Prevent io from disappearing until this function completes.
1087 */
1088 crypt_inc_pending(io);
Milan Brozb635b002008-10-21 17:45:00 +01001089 crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
Milan Brozfc5a5e92008-10-10 13:37:04 +01001090
1091 /*
Milan Broz93e605c2006-10-03 01:15:38 -07001092 * The allocated buffers can be smaller than the whole bio,
1093 * so repeat the whole process until all the data can be handled.
1094 */
1095 while (remaining) {
Milan Broz933f01d2008-10-10 13:37:08 +01001096 clone = crypt_alloc_buffer(io, remaining, &out_of_pages);
Milan Broz23541d22006-10-03 01:15:39 -07001097 if (unlikely(!clone)) {
Milan Broz5742fd72008-02-08 02:10:43 +00001098 io->error = -ENOMEM;
Milan Brozfc5a5e92008-10-10 13:37:04 +01001099 break;
Milan Broz23541d22006-10-03 01:15:39 -07001100 }
Milan Broz93e605c2006-10-03 01:15:38 -07001101
Milan Broz53017032008-02-08 02:10:38 +00001102 io->ctx.bio_out = clone;
1103 io->ctx.idx_out = 0;
Milan Broz93e605c2006-10-03 01:15:38 -07001104
Milan Broz93e605c2006-10-03 01:15:38 -07001105 remaining -= clone->bi_size;
Milan Brozb635b002008-10-21 17:45:00 +01001106 sector += bio_sectors(clone);
Milan Brozdec1ced2008-02-08 02:10:57 +00001107
Milan Broz4e594092008-10-10 13:37:07 +01001108 crypt_inc_pending(io);
Milan Brozdec1ced2008-02-08 02:10:57 +00001109 r = crypt_convert(cc, &io->ctx);
Milan Brozc8081612008-10-10 13:37:08 +01001110 crypt_finished = atomic_dec_and_test(&io->ctx.pending);
Milan Brozdec1ced2008-02-08 02:10:57 +00001111
Milan Brozc8081612008-10-10 13:37:08 +01001112 /* Encryption was already finished, submit io now */
1113 if (crypt_finished) {
Milan Broz3a7f6c92008-02-08 02:11:14 +00001114 kcryptd_crypt_write_io_submit(io, r, 0);
Milan Brozc8081612008-10-10 13:37:08 +01001115
1116 /*
1117 * If there was an error, do not try next fragments.
1118 * For async, error is processed in async handler.
1119 */
Milan Broz6c031f42008-10-10 13:37:06 +01001120 if (unlikely(r < 0))
Milan Brozfc5a5e92008-10-10 13:37:04 +01001121 break;
Milan Brozb635b002008-10-21 17:45:00 +01001122
1123 io->sector = sector;
Milan Broz4e594092008-10-10 13:37:07 +01001124 }
Milan Broz93e605c2006-10-03 01:15:38 -07001125
Milan Broz933f01d2008-10-10 13:37:08 +01001126 /*
1127 * Out of memory -> run queues
1128 * But don't wait if split was due to the io size restriction
1129 */
1130 if (unlikely(out_of_pages))
Jens Axboe8aa7e842009-07-09 14:52:32 +02001131 congestion_wait(BLK_RW_ASYNC, HZ/100);
Milan Broz933f01d2008-10-10 13:37:08 +01001132
Milan Broz393b47e2008-10-21 17:45:02 +01001133 /*
1134 * With async crypto it is unsafe to share the crypto context
1135 * between fragments, so switch to a new dm_crypt_io structure.
1136 */
1137 if (unlikely(!crypt_finished && remaining)) {
1138 new_io = crypt_io_alloc(io->target, io->base_bio,
1139 sector);
1140 crypt_inc_pending(new_io);
1141 crypt_convert_init(cc, &new_io->ctx, NULL,
1142 io->base_bio, sector);
1143 new_io->ctx.idx_in = io->ctx.idx_in;
1144 new_io->ctx.offset_in = io->ctx.offset_in;
1145
1146 /*
1147 * Fragments after the first use the base_io
1148 * pending count.
1149 */
1150 if (!io->base_io)
1151 new_io->base_io = io;
1152 else {
1153 new_io->base_io = io->base_io;
1154 crypt_inc_pending(io->base_io);
1155 crypt_dec_pending(io);
1156 }
1157
1158 io = new_io;
1159 }
Milan Broz8b004452006-10-03 01:15:37 -07001160 }
Milan Broz899c95d2008-02-08 02:11:02 +00001161
1162 crypt_dec_pending(io);
Milan Broz84131db2008-02-08 02:10:59 +00001163}
1164
Milan Broz4e4eef62008-02-08 02:10:49 +00001165static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error)
Milan Broz5742fd72008-02-08 02:10:43 +00001166{
1167 if (unlikely(error < 0))
1168 io->error = -EIO;
1169
1170 crypt_dec_pending(io);
1171}
1172
Milan Broz4e4eef62008-02-08 02:10:49 +00001173static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
Milan Broz8b004452006-10-03 01:15:37 -07001174{
1175 struct crypt_config *cc = io->target->private;
Milan Broz5742fd72008-02-08 02:10:43 +00001176 int r = 0;
Milan Broz8b004452006-10-03 01:15:37 -07001177
Milan Broz3e1a8bd2008-10-10 13:37:02 +01001178 crypt_inc_pending(io);
Milan Broz3a7f6c92008-02-08 02:11:14 +00001179
Milan Broz53017032008-02-08 02:10:38 +00001180 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
Milan Broz0c395b02008-02-08 02:10:54 +00001181 io->sector);
Milan Broz8b004452006-10-03 01:15:37 -07001182
Milan Broz5742fd72008-02-08 02:10:43 +00001183 r = crypt_convert(cc, &io->ctx);
1184
Milan Broz3f1e9072008-03-28 14:16:07 -07001185 if (atomic_dec_and_test(&io->ctx.pending))
Milan Broz3a7f6c92008-02-08 02:11:14 +00001186 kcryptd_crypt_read_done(io, r);
1187
1188 crypt_dec_pending(io);
Milan Broz8b004452006-10-03 01:15:37 -07001189}
1190
Milan Broz95497a92008-02-08 02:11:12 +00001191static void kcryptd_async_done(struct crypto_async_request *async_req,
1192 int error)
1193{
Huang Yingb2174ee2009-03-16 17:44:33 +00001194 struct dm_crypt_request *dmreq = async_req->data;
1195 struct convert_context *ctx = dmreq->ctx;
Milan Broz95497a92008-02-08 02:11:12 +00001196 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1197 struct crypt_config *cc = io->target->private;
1198
1199 if (error == -EINPROGRESS) {
1200 complete(&ctx->restart);
1201 return;
1202 }
1203
Milan Broz2dc53272011-01-13 19:59:54 +00001204 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
1205 error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq);
1206
Huang Yingb2174ee2009-03-16 17:44:33 +00001207 mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
Milan Broz95497a92008-02-08 02:11:12 +00001208
1209 if (!atomic_dec_and_test(&ctx->pending))
1210 return;
1211
1212 if (bio_data_dir(io->base_bio) == READ)
1213 kcryptd_crypt_read_done(io, error);
1214 else
1215 kcryptd_crypt_write_io_submit(io, error, 1);
1216}
1217
Milan Broz4e4eef62008-02-08 02:10:49 +00001218static void kcryptd_crypt(struct work_struct *work)
1219{
1220 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1221
1222 if (bio_data_dir(io->base_bio) == READ)
1223 kcryptd_crypt_read_convert(io);
1224 else
1225 kcryptd_crypt_write_convert(io);
Milan Broz8b004452006-10-03 01:15:37 -07001226}
1227
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001228static void kcryptd_queue_crypt(struct dm_crypt_io *io)
1229{
1230 struct crypt_config *cc = io->target->private;
1231
1232 INIT_WORK(&io->work, kcryptd_crypt);
1233 queue_work(cc->crypt_queue, &io->work);
1234}
1235
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236/*
1237 * Decode key from its hex representation
1238 */
1239static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
1240{
1241 char buffer[3];
1242 char *endp;
1243 unsigned int i;
1244
1245 buffer[2] = '\0';
1246
Milan Broz8b004452006-10-03 01:15:37 -07001247 for (i = 0; i < size; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248 buffer[0] = *hex++;
1249 buffer[1] = *hex++;
1250
1251 key[i] = (u8)simple_strtoul(buffer, &endp, 16);
1252
1253 if (endp != &buffer[2])
1254 return -EINVAL;
1255 }
1256
1257 if (*hex != '\0')
1258 return -EINVAL;
1259
1260 return 0;
1261}
1262
1263/*
1264 * Encode key into its hex representation
1265 */
1266static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
1267{
1268 unsigned int i;
1269
Milan Broz8b004452006-10-03 01:15:37 -07001270 for (i = 0; i < size; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001271 sprintf(hex, "%02x", *key);
1272 hex += 2;
1273 key++;
1274 }
1275}
1276
Milan Brozd1f96422011-01-13 19:59:54 +00001277static void crypt_free_tfms(struct crypt_config *cc, int cpu)
1278{
1279 struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1280 unsigned i;
1281
1282 for (i = 0; i < cc->tfms_count; i++)
1283 if (cpu_cc->tfms[i] && !IS_ERR(cpu_cc->tfms[i])) {
1284 crypto_free_ablkcipher(cpu_cc->tfms[i]);
1285 cpu_cc->tfms[i] = NULL;
1286 }
1287}
1288
1289static int crypt_alloc_tfms(struct crypt_config *cc, int cpu, char *ciphermode)
1290{
1291 struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1292 unsigned i;
1293 int err;
1294
1295 for (i = 0; i < cc->tfms_count; i++) {
1296 cpu_cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
1297 if (IS_ERR(cpu_cc->tfms[i])) {
1298 err = PTR_ERR(cpu_cc->tfms[i]);
1299 crypt_free_tfms(cc, cpu);
1300 return err;
1301 }
1302 }
1303
1304 return 0;
1305}
1306
Andi Kleenc0297722011-01-13 19:59:53 +00001307static int crypt_setkey_allcpus(struct crypt_config *cc)
1308{
Milan Brozd1f96422011-01-13 19:59:54 +00001309 unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count);
1310 int cpu, err = 0, i, r;
Andi Kleenc0297722011-01-13 19:59:53 +00001311
1312 for_each_possible_cpu(cpu) {
Milan Brozd1f96422011-01-13 19:59:54 +00001313 for (i = 0; i < cc->tfms_count; i++) {
1314 r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfms[i],
1315 cc->key + (i * subkey_size), subkey_size);
1316 if (r)
1317 err = r;
1318 }
Andi Kleenc0297722011-01-13 19:59:53 +00001319 }
1320
1321 return err;
1322}
1323
Milan Broze48d4bb2006-10-03 01:15:37 -07001324static int crypt_set_key(struct crypt_config *cc, char *key)
1325{
Milan Brozde8be5a2011-03-24 13:54:27 +00001326 int r = -EINVAL;
1327 int key_string_len = strlen(key);
1328
Milan Broz69a8cfc2011-01-13 19:59:49 +00001329 /* The key size may not be changed. */
Milan Brozde8be5a2011-03-24 13:54:27 +00001330 if (cc->key_size != (key_string_len >> 1))
1331 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001332
Milan Broz69a8cfc2011-01-13 19:59:49 +00001333 /* Hyphen (which gives a key_size of zero) means there is no key. */
1334 if (!cc->key_size && strcmp(key, "-"))
Milan Brozde8be5a2011-03-24 13:54:27 +00001335 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001336
Milan Broz69a8cfc2011-01-13 19:59:49 +00001337 if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
Milan Brozde8be5a2011-03-24 13:54:27 +00001338 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001339
1340 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1341
Milan Brozde8be5a2011-03-24 13:54:27 +00001342 r = crypt_setkey_allcpus(cc);
1343
1344out:
1345 /* Hex key string not needed after here, so wipe it. */
1346 memset(key, '0', key_string_len);
1347
1348 return r;
Milan Broze48d4bb2006-10-03 01:15:37 -07001349}
1350
1351static int crypt_wipe_key(struct crypt_config *cc)
1352{
1353 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1354 memset(&cc->key, 0, cc->key_size * sizeof(u8));
Andi Kleenc0297722011-01-13 19:59:53 +00001355
1356 return crypt_setkey_allcpus(cc);
Milan Broze48d4bb2006-10-03 01:15:37 -07001357}
1358
Milan Broz28513fc2010-08-12 04:14:06 +01001359static void crypt_dtr(struct dm_target *ti)
1360{
1361 struct crypt_config *cc = ti->private;
Andi Kleenc0297722011-01-13 19:59:53 +00001362 struct crypt_cpu *cpu_cc;
1363 int cpu;
Milan Broz28513fc2010-08-12 04:14:06 +01001364
1365 ti->private = NULL;
1366
1367 if (!cc)
1368 return;
1369
1370 if (cc->io_queue)
1371 destroy_workqueue(cc->io_queue);
1372 if (cc->crypt_queue)
1373 destroy_workqueue(cc->crypt_queue);
1374
Andi Kleenc0297722011-01-13 19:59:53 +00001375 if (cc->cpu)
1376 for_each_possible_cpu(cpu) {
1377 cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1378 if (cpu_cc->req)
1379 mempool_free(cpu_cc->req, cc->req_pool);
Milan Brozd1f96422011-01-13 19:59:54 +00001380 crypt_free_tfms(cc, cpu);
Andi Kleenc0297722011-01-13 19:59:53 +00001381 }
1382
Milan Broz28513fc2010-08-12 04:14:06 +01001383 if (cc->bs)
1384 bioset_free(cc->bs);
1385
1386 if (cc->page_pool)
1387 mempool_destroy(cc->page_pool);
1388 if (cc->req_pool)
1389 mempool_destroy(cc->req_pool);
1390 if (cc->io_pool)
1391 mempool_destroy(cc->io_pool);
1392
1393 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
1394 cc->iv_gen_ops->dtr(cc);
1395
Milan Broz28513fc2010-08-12 04:14:06 +01001396 if (cc->dev)
1397 dm_put_device(ti, cc->dev);
1398
Andi Kleenc0297722011-01-13 19:59:53 +00001399 if (cc->cpu)
1400 free_percpu(cc->cpu);
1401
Milan Broz5ebaee62010-08-12 04:14:07 +01001402 kzfree(cc->cipher);
Milan Broz7dbcd132011-01-13 19:59:52 +00001403 kzfree(cc->cipher_string);
Milan Broz28513fc2010-08-12 04:14:06 +01001404
1405 /* Must zero key material before freeing */
1406 kzfree(cc);
1407}
1408
Milan Broz5ebaee62010-08-12 04:14:07 +01001409static int crypt_ctr_cipher(struct dm_target *ti,
1410 char *cipher_in, char *key)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411{
Milan Broz5ebaee62010-08-12 04:14:07 +01001412 struct crypt_config *cc = ti->private;
Milan Brozd1f96422011-01-13 19:59:54 +00001413 char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
Milan Broz5ebaee62010-08-12 04:14:07 +01001414 char *cipher_api = NULL;
Andi Kleenc0297722011-01-13 19:59:53 +00001415 int cpu, ret = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416
Milan Broz5ebaee62010-08-12 04:14:07 +01001417 /* Convert to crypto api definition? */
1418 if (strchr(cipher_in, '(')) {
1419 ti->error = "Bad cipher specification";
Linus Torvalds1da177e2005-04-16 15:20:36 -07001420 return -EINVAL;
1421 }
1422
Milan Broz7dbcd132011-01-13 19:59:52 +00001423 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
1424 if (!cc->cipher_string)
1425 goto bad_mem;
1426
Milan Broz5ebaee62010-08-12 04:14:07 +01001427 /*
1428 * Legacy dm-crypt cipher specification
Milan Brozd1f96422011-01-13 19:59:54 +00001429 * cipher[:keycount]-mode-iv:ivopts
Milan Broz5ebaee62010-08-12 04:14:07 +01001430 */
1431 tmp = cipher_in;
Milan Brozd1f96422011-01-13 19:59:54 +00001432 keycount = strsep(&tmp, "-");
1433 cipher = strsep(&keycount, ":");
1434
1435 if (!keycount)
1436 cc->tfms_count = 1;
1437 else if (sscanf(keycount, "%u", &cc->tfms_count) != 1 ||
1438 !is_power_of_2(cc->tfms_count)) {
1439 ti->error = "Bad cipher key count specification";
1440 return -EINVAL;
1441 }
1442 cc->key_parts = cc->tfms_count;
Milan Broz5ebaee62010-08-12 04:14:07 +01001443
1444 cc->cipher = kstrdup(cipher, GFP_KERNEL);
1445 if (!cc->cipher)
1446 goto bad_mem;
1447
Linus Torvalds1da177e2005-04-16 15:20:36 -07001448 chainmode = strsep(&tmp, "-");
1449 ivopts = strsep(&tmp, "-");
1450 ivmode = strsep(&ivopts, ":");
1451
1452 if (tmp)
Milan Broz5ebaee62010-08-12 04:14:07 +01001453 DMWARN("Ignoring unexpected additional cipher options");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454
Milan Brozd1f96422011-01-13 19:59:54 +00001455 cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)) +
1456 cc->tfms_count * sizeof(*(cc->cpu->tfms)),
1457 __alignof__(struct crypt_cpu));
Andi Kleenc0297722011-01-13 19:59:53 +00001458 if (!cc->cpu) {
1459 ti->error = "Cannot allocate per cpu state";
1460 goto bad_mem;
1461 }
1462
Milan Broz7dbcd132011-01-13 19:59:52 +00001463 /*
1464 * For compatibility with the original dm-crypt mapping format, if
1465 * only the cipher name is supplied, use cbc-plain.
1466 */
Milan Broz5ebaee62010-08-12 04:14:07 +01001467 if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468 chainmode = "cbc";
1469 ivmode = "plain";
1470 }
1471
Herbert Xud1806f62006-08-22 20:29:17 +10001472 if (strcmp(chainmode, "ecb") && !ivmode) {
Milan Broz5ebaee62010-08-12 04:14:07 +01001473 ti->error = "IV mechanism required";
1474 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475 }
1476
Milan Broz5ebaee62010-08-12 04:14:07 +01001477 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
1478 if (!cipher_api)
1479 goto bad_mem;
1480
1481 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
1482 "%s(%s)", chainmode, cipher);
1483 if (ret < 0) {
1484 kfree(cipher_api);
1485 goto bad_mem;
Herbert Xud1806f62006-08-22 20:29:17 +10001486 }
1487
Milan Broz5ebaee62010-08-12 04:14:07 +01001488 /* Allocate cipher */
Andi Kleenc0297722011-01-13 19:59:53 +00001489 for_each_possible_cpu(cpu) {
Milan Brozd1f96422011-01-13 19:59:54 +00001490 ret = crypt_alloc_tfms(cc, cpu, cipher_api);
1491 if (ret < 0) {
Andi Kleenc0297722011-01-13 19:59:53 +00001492 ti->error = "Error allocating crypto tfm";
1493 goto bad;
1494 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496
Milan Broz5ebaee62010-08-12 04:14:07 +01001497 /* Initialize and set key */
1498 ret = crypt_set_key(cc, key);
Milan Broz28513fc2010-08-12 04:14:06 +01001499 if (ret < 0) {
Milan Broz0b430952009-12-10 23:51:55 +00001500 ti->error = "Error decoding and setting key";
Milan Broz28513fc2010-08-12 04:14:06 +01001501 goto bad;
Milan Broz0b430952009-12-10 23:51:55 +00001502 }
1503
Milan Broz5ebaee62010-08-12 04:14:07 +01001504 /* Initialize IV */
Andi Kleenc0297722011-01-13 19:59:53 +00001505 cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
Milan Broz5ebaee62010-08-12 04:14:07 +01001506 if (cc->iv_size)
1507 /* at least a 64 bit sector number should fit in our buffer */
1508 cc->iv_size = max(cc->iv_size,
1509 (unsigned int)(sizeof(u64) / sizeof(u8)));
1510 else if (ivmode) {
1511 DMWARN("Selected cipher does not support IVs");
1512 ivmode = NULL;
1513 }
1514
1515 /* Choose ivmode, see comments at iv code. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001516 if (ivmode == NULL)
1517 cc->iv_gen_ops = NULL;
1518 else if (strcmp(ivmode, "plain") == 0)
1519 cc->iv_gen_ops = &crypt_iv_plain_ops;
Milan Broz61afef62009-12-10 23:52:25 +00001520 else if (strcmp(ivmode, "plain64") == 0)
1521 cc->iv_gen_ops = &crypt_iv_plain64_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001522 else if (strcmp(ivmode, "essiv") == 0)
1523 cc->iv_gen_ops = &crypt_iv_essiv_ops;
Rik Snel48527fa2006-09-03 08:56:39 +10001524 else if (strcmp(ivmode, "benbi") == 0)
1525 cc->iv_gen_ops = &crypt_iv_benbi_ops;
Ludwig Nussel46b47732007-05-09 02:32:55 -07001526 else if (strcmp(ivmode, "null") == 0)
1527 cc->iv_gen_ops = &crypt_iv_null_ops;
Milan Broz34745782011-01-13 19:59:55 +00001528 else if (strcmp(ivmode, "lmk") == 0) {
1529 cc->iv_gen_ops = &crypt_iv_lmk_ops;
1530 /* Version 2 and 3 is recognised according
1531 * to length of provided multi-key string.
1532 * If present (version 3), last key is used as IV seed.
1533 */
1534 if (cc->key_size % cc->key_parts)
1535 cc->key_parts++;
1536 } else {
Milan Broz5ebaee62010-08-12 04:14:07 +01001537 ret = -EINVAL;
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001538 ti->error = "Invalid IV mode";
Milan Broz28513fc2010-08-12 04:14:06 +01001539 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001540 }
1541
Milan Broz28513fc2010-08-12 04:14:06 +01001542 /* Allocate IV */
1543 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
1544 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
1545 if (ret < 0) {
1546 ti->error = "Error creating IV";
1547 goto bad;
1548 }
Milan Brozb95bf2d2009-12-10 23:51:56 +00001549 }
1550
Milan Broz28513fc2010-08-12 04:14:06 +01001551 /* Initialize IV (set keys for ESSIV etc) */
1552 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
1553 ret = cc->iv_gen_ops->init(cc);
1554 if (ret < 0) {
1555 ti->error = "Error initialising IV";
1556 goto bad;
1557 }
1558 }
1559
Milan Broz5ebaee62010-08-12 04:14:07 +01001560 ret = 0;
1561bad:
1562 kfree(cipher_api);
1563 return ret;
1564
1565bad_mem:
1566 ti->error = "Cannot allocate cipher strings";
1567 return -ENOMEM;
1568}
1569
1570/*
1571 * Construct an encryption mapping:
1572 * <cipher> <key> <iv_offset> <dev_path> <start>
1573 */
1574static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
1575{
1576 struct crypt_config *cc;
Milan Broz772ae5f2011-08-02 12:32:08 +01001577 unsigned int key_size, opt_params;
Milan Broz5ebaee62010-08-12 04:14:07 +01001578 unsigned long long tmpll;
1579 int ret;
Milan Broz772ae5f2011-08-02 12:32:08 +01001580 struct dm_arg_set as;
1581 const char *opt_string;
Milan Broz5ebaee62010-08-12 04:14:07 +01001582
Milan Broz772ae5f2011-08-02 12:32:08 +01001583 static struct dm_arg _args[] = {
1584 {0, 1, "Invalid number of feature args"},
1585 };
1586
1587 if (argc < 5) {
Milan Broz5ebaee62010-08-12 04:14:07 +01001588 ti->error = "Not enough arguments";
1589 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001590 }
1591
Milan Broz5ebaee62010-08-12 04:14:07 +01001592 key_size = strlen(argv[1]) >> 1;
1593
1594 cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);
1595 if (!cc) {
1596 ti->error = "Cannot allocate encryption context";
1597 return -ENOMEM;
1598 }
Milan Broz69a8cfc2011-01-13 19:59:49 +00001599 cc->key_size = key_size;
Milan Broz5ebaee62010-08-12 04:14:07 +01001600
1601 ti->private = cc;
1602 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
1603 if (ret < 0)
1604 goto bad;
1605
Milan Broz28513fc2010-08-12 04:14:06 +01001606 ret = -ENOMEM;
Matthew Dobson93d23412006-03-26 01:37:50 -08001607 cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608 if (!cc->io_pool) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001609 ti->error = "Cannot allocate crypt io mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001610 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001611 }
1612
Milan Brozddd42ed2008-02-08 02:11:07 +00001613 cc->dmreq_start = sizeof(struct ablkcipher_request);
Andi Kleenc0297722011-01-13 19:59:53 +00001614 cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
Milan Brozddd42ed2008-02-08 02:11:07 +00001615 cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
Andi Kleenc0297722011-01-13 19:59:53 +00001616 cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) &
Milan Broz3a7f6c92008-02-08 02:11:14 +00001617 ~(crypto_tfm_ctx_alignment() - 1);
Milan Brozddd42ed2008-02-08 02:11:07 +00001618
1619 cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
1620 sizeof(struct dm_crypt_request) + cc->iv_size);
1621 if (!cc->req_pool) {
1622 ti->error = "Cannot allocate crypt request mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001623 goto bad;
Milan Brozddd42ed2008-02-08 02:11:07 +00001624 }
Milan Brozddd42ed2008-02-08 02:11:07 +00001625
Matthew Dobsona19b27c2006-03-26 01:37:45 -08001626 cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001627 if (!cc->page_pool) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001628 ti->error = "Cannot allocate page mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001629 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001630 }
1631
Jens Axboebb799ca2008-12-10 15:35:05 +01001632 cc->bs = bioset_create(MIN_IOS, 0);
Milan Broz6a24c712006-10-03 01:15:40 -07001633 if (!cc->bs) {
1634 ti->error = "Cannot allocate crypt bioset";
Milan Broz28513fc2010-08-12 04:14:06 +01001635 goto bad;
Milan Broz6a24c712006-10-03 01:15:40 -07001636 }
1637
Milan Broz28513fc2010-08-12 04:14:06 +01001638 ret = -EINVAL;
Andrew Morton4ee218c2006-03-27 01:17:48 -08001639 if (sscanf(argv[2], "%llu", &tmpll) != 1) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001640 ti->error = "Invalid iv_offset sector";
Milan Broz28513fc2010-08-12 04:14:06 +01001641 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642 }
Andrew Morton4ee218c2006-03-27 01:17:48 -08001643 cc->iv_offset = tmpll;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001644
Milan Broz28513fc2010-08-12 04:14:06 +01001645 if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) {
1646 ti->error = "Device lookup failed";
1647 goto bad;
1648 }
1649
Andrew Morton4ee218c2006-03-27 01:17:48 -08001650 if (sscanf(argv[4], "%llu", &tmpll) != 1) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001651 ti->error = "Invalid device sector";
Milan Broz28513fc2010-08-12 04:14:06 +01001652 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653 }
Andrew Morton4ee218c2006-03-27 01:17:48 -08001654 cc->start = tmpll;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655
Milan Broz772ae5f2011-08-02 12:32:08 +01001656 argv += 5;
1657 argc -= 5;
1658
1659 /* Optional parameters */
1660 if (argc) {
1661 as.argc = argc;
1662 as.argv = argv;
1663
1664 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
1665 if (ret)
1666 goto bad;
1667
1668 opt_string = dm_shift_arg(&as);
1669
1670 if (opt_params == 1 && opt_string &&
1671 !strcasecmp(opt_string, "allow_discards"))
1672 ti->num_discard_requests = 1;
1673 else if (opt_params) {
1674 ret = -EINVAL;
1675 ti->error = "Invalid feature arguments";
1676 goto bad;
1677 }
1678 }
1679
Milan Broz28513fc2010-08-12 04:14:06 +01001680 ret = -ENOMEM;
Andi Kleenc0297722011-01-13 19:59:53 +00001681 cc->io_queue = alloc_workqueue("kcryptd_io",
1682 WQ_NON_REENTRANT|
1683 WQ_MEM_RECLAIM,
1684 1);
Milan Brozcabf08e2007-10-19 22:38:58 +01001685 if (!cc->io_queue) {
1686 ti->error = "Couldn't create kcryptd io queue";
Milan Broz28513fc2010-08-12 04:14:06 +01001687 goto bad;
Milan Brozcabf08e2007-10-19 22:38:58 +01001688 }
1689
Andi Kleenc0297722011-01-13 19:59:53 +00001690 cc->crypt_queue = alloc_workqueue("kcryptd",
1691 WQ_NON_REENTRANT|
1692 WQ_CPU_INTENSIVE|
1693 WQ_MEM_RECLAIM,
1694 1);
Milan Brozcabf08e2007-10-19 22:38:58 +01001695 if (!cc->crypt_queue) {
Milan Broz9934a8b2007-10-19 22:38:57 +01001696 ti->error = "Couldn't create kcryptd queue";
Milan Broz28513fc2010-08-12 04:14:06 +01001697 goto bad;
Milan Broz9934a8b2007-10-19 22:38:57 +01001698 }
1699
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001700 ti->num_flush_requests = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001701 return 0;
1702
Milan Broz28513fc2010-08-12 04:14:06 +01001703bad:
1704 crypt_dtr(ti);
1705 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001706}
1707
Linus Torvalds1da177e2005-04-16 15:20:36 -07001708static int crypt_map(struct dm_target *ti, struct bio *bio,
1709 union map_info *map_context)
1710{
Alasdair G Kergon028867a2007-07-12 17:26:32 +01001711 struct dm_crypt_io *io;
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001712 struct crypt_config *cc;
1713
Milan Broz772ae5f2011-08-02 12:32:08 +01001714 /*
1715 * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
1716 * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight
1717 * - for REQ_DISCARD caller must use flush if IO ordering matters
1718 */
1719 if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001720 cc = ti->private;
1721 bio->bi_bdev = cc->dev->bdev;
Milan Broz772ae5f2011-08-02 12:32:08 +01001722 if (bio_sectors(bio))
1723 bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector);
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001724 return DM_MAPIO_REMAPPED;
1725 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001726
Alasdair G Kergonb441a2622010-08-12 04:14:11 +01001727 io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector));
Milan Brozcabf08e2007-10-19 22:38:58 +01001728
Milan Broz20c82532011-01-13 19:59:53 +00001729 if (bio_data_dir(io->base_bio) == READ) {
1730 if (kcryptd_io_read(io, GFP_NOWAIT))
1731 kcryptd_queue_io(io);
1732 } else
Milan Brozcabf08e2007-10-19 22:38:58 +01001733 kcryptd_queue_crypt(io);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001734
Kiyoshi Uedad2a7ad22006-12-08 02:41:06 -08001735 return DM_MAPIO_SUBMITTED;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001736}
1737
1738static int crypt_status(struct dm_target *ti, status_type_t type,
1739 char *result, unsigned int maxlen)
1740{
Milan Broz5ebaee62010-08-12 04:14:07 +01001741 struct crypt_config *cc = ti->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742 unsigned int sz = 0;
1743
1744 switch (type) {
1745 case STATUSTYPE_INFO:
1746 result[0] = '\0';
1747 break;
1748
1749 case STATUSTYPE_TABLE:
Milan Broz7dbcd132011-01-13 19:59:52 +00001750 DMEMIT("%s ", cc->cipher_string);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001751
1752 if (cc->key_size > 0) {
1753 if ((maxlen - sz) < ((cc->key_size << 1) + 1))
1754 return -ENOMEM;
1755
1756 crypt_encode_key(result + sz, cc->key, cc->key_size);
1757 sz += cc->key_size << 1;
1758 } else {
1759 if (sz >= maxlen)
1760 return -ENOMEM;
1761 result[sz++] = '-';
1762 }
1763
Andrew Morton4ee218c2006-03-27 01:17:48 -08001764 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
1765 cc->dev->name, (unsigned long long)cc->start);
Milan Broz772ae5f2011-08-02 12:32:08 +01001766
1767 if (ti->num_discard_requests)
1768 DMEMIT(" 1 allow_discards");
1769
Linus Torvalds1da177e2005-04-16 15:20:36 -07001770 break;
1771 }
1772 return 0;
1773}
1774
Milan Broze48d4bb2006-10-03 01:15:37 -07001775static void crypt_postsuspend(struct dm_target *ti)
1776{
1777 struct crypt_config *cc = ti->private;
1778
1779 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1780}
1781
1782static int crypt_preresume(struct dm_target *ti)
1783{
1784 struct crypt_config *cc = ti->private;
1785
1786 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
1787 DMERR("aborting resume - crypt key is not set.");
1788 return -EAGAIN;
1789 }
1790
1791 return 0;
1792}
1793
1794static void crypt_resume(struct dm_target *ti)
1795{
1796 struct crypt_config *cc = ti->private;
1797
1798 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1799}
1800
1801/* Message interface
1802 * key set <key>
1803 * key wipe
1804 */
1805static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
1806{
1807 struct crypt_config *cc = ti->private;
Milan Broz542da312009-12-10 23:51:57 +00001808 int ret = -EINVAL;
Milan Broze48d4bb2006-10-03 01:15:37 -07001809
1810 if (argc < 2)
1811 goto error;
1812
Mike Snitzer498f0102011-08-02 12:32:04 +01001813 if (!strcasecmp(argv[0], "key")) {
Milan Broze48d4bb2006-10-03 01:15:37 -07001814 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
1815 DMWARN("not suspended during key manipulation.");
1816 return -EINVAL;
1817 }
Mike Snitzer498f0102011-08-02 12:32:04 +01001818 if (argc == 3 && !strcasecmp(argv[1], "set")) {
Milan Broz542da312009-12-10 23:51:57 +00001819 ret = crypt_set_key(cc, argv[2]);
1820 if (ret)
1821 return ret;
1822 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
1823 ret = cc->iv_gen_ops->init(cc);
1824 return ret;
1825 }
Mike Snitzer498f0102011-08-02 12:32:04 +01001826 if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
Milan Broz542da312009-12-10 23:51:57 +00001827 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
1828 ret = cc->iv_gen_ops->wipe(cc);
1829 if (ret)
1830 return ret;
1831 }
Milan Broze48d4bb2006-10-03 01:15:37 -07001832 return crypt_wipe_key(cc);
Milan Broz542da312009-12-10 23:51:57 +00001833 }
Milan Broze48d4bb2006-10-03 01:15:37 -07001834 }
1835
1836error:
1837 DMWARN("unrecognised message received.");
1838 return -EINVAL;
1839}
1840
Milan Brozd41e26b2008-07-21 12:00:40 +01001841static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
1842 struct bio_vec *biovec, int max_size)
1843{
1844 struct crypt_config *cc = ti->private;
1845 struct request_queue *q = bdev_get_queue(cc->dev->bdev);
1846
1847 if (!q->merge_bvec_fn)
1848 return max_size;
1849
1850 bvm->bi_bdev = cc->dev->bdev;
Alasdair G Kergonb441a2622010-08-12 04:14:11 +01001851 bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector);
Milan Brozd41e26b2008-07-21 12:00:40 +01001852
1853 return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
1854}
1855
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001856static int crypt_iterate_devices(struct dm_target *ti,
1857 iterate_devices_callout_fn fn, void *data)
1858{
1859 struct crypt_config *cc = ti->private;
1860
Mike Snitzer5dea2712009-07-23 20:30:42 +01001861 return fn(ti, cc->dev, cc->start, ti->len, data);
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001862}
1863
Linus Torvalds1da177e2005-04-16 15:20:36 -07001864static struct target_type crypt_target = {
1865 .name = "crypt",
Milan Broz772ae5f2011-08-02 12:32:08 +01001866 .version = {1, 11, 0},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001867 .module = THIS_MODULE,
1868 .ctr = crypt_ctr,
1869 .dtr = crypt_dtr,
1870 .map = crypt_map,
1871 .status = crypt_status,
Milan Broze48d4bb2006-10-03 01:15:37 -07001872 .postsuspend = crypt_postsuspend,
1873 .preresume = crypt_preresume,
1874 .resume = crypt_resume,
1875 .message = crypt_message,
Milan Brozd41e26b2008-07-21 12:00:40 +01001876 .merge = crypt_merge,
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001877 .iterate_devices = crypt_iterate_devices,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001878};
1879
1880static int __init dm_crypt_init(void)
1881{
1882 int r;
1883
Alasdair G Kergon028867a2007-07-12 17:26:32 +01001884 _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001885 if (!_crypt_io_pool)
1886 return -ENOMEM;
1887
Linus Torvalds1da177e2005-04-16 15:20:36 -07001888 r = dm_register_target(&crypt_target);
1889 if (r < 0) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001890 DMERR("register failed %d", r);
Milan Broz9934a8b2007-10-19 22:38:57 +01001891 kmem_cache_destroy(_crypt_io_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001892 }
1893
Linus Torvalds1da177e2005-04-16 15:20:36 -07001894 return r;
1895}
1896
1897static void __exit dm_crypt_exit(void)
1898{
Mikulas Patocka10d3bd02009-01-06 03:04:58 +00001899 dm_unregister_target(&crypt_target);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001900 kmem_cache_destroy(_crypt_io_pool);
1901}
1902
1903module_init(dm_crypt_init);
1904module_exit(dm_crypt_exit);
1905
1906MODULE_AUTHOR("Christophe Saout <christophe@saout.de>");
1907MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
1908MODULE_LICENSE("GPL");