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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;
Mikulas Patockac66029f2012-07-27 15:08:05 +010045 sector_t cc_sector;
Mikulas Patocka40b62292012-07-27 15:08:04 +010046 atomic_t cc_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 {
Alasdair G Kergon49a8a922012-07-27 15:08:05 +010053 struct crypt_config *cc;
Milan Broz53017032008-02-08 02:10:38 +000054 struct bio *base_bio;
55 struct work_struct work;
56
57 struct convert_context ctx;
58
Mikulas Patocka40b62292012-07-27 15:08:04 +010059 atomic_t io_pending;
Milan Broz53017032008-02-08 02:10:38 +000060 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};
113
114/*
115 * The fields in here must be read only after initialization,
116 * changing state should be in crypt_cpu.
117 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118struct crypt_config {
119 struct dm_dev *dev;
120 sector_t start;
121
122 /*
Milan Brozddd42ed2008-02-08 02:11:07 +0000123 * pool for per bio private data, crypto requests and
124 * encryption requeusts/buffer pages
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 */
126 mempool_t *io_pool;
Milan Brozddd42ed2008-02-08 02:11:07 +0000127 mempool_t *req_pool;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 mempool_t *page_pool;
Milan Broz6a24c712006-10-03 01:15:40 -0700129 struct bio_set *bs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130
Milan Brozcabf08e2007-10-19 22:38:58 +0100131 struct workqueue_struct *io_queue;
132 struct workqueue_struct *crypt_queue;
Milan Broz3f1e9072008-03-28 14:16:07 -0700133
Milan Broz5ebaee62010-08-12 04:14:07 +0100134 char *cipher;
Milan Broz7dbcd132011-01-13 19:59:52 +0000135 char *cipher_string;
Milan Broz5ebaee62010-08-12 04:14:07 +0100136
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 struct crypt_iv_operations *iv_gen_ops;
Herbert Xu79066ad2006-12-05 13:41:52 -0800138 union {
Milan Broz60473592009-12-10 23:51:55 +0000139 struct iv_essiv_private essiv;
140 struct iv_benbi_private benbi;
Milan Broz34745782011-01-13 19:59:55 +0000141 struct iv_lmk_private lmk;
Herbert Xu79066ad2006-12-05 13:41:52 -0800142 } iv_gen_private;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 sector_t iv_offset;
144 unsigned int iv_size;
145
Milan Brozddd42ed2008-02-08 02:11:07 +0000146 /*
Andi Kleenc0297722011-01-13 19:59:53 +0000147 * Duplicated per cpu state. Access through
148 * per_cpu_ptr() only.
149 */
150 struct crypt_cpu __percpu *cpu;
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100151
152 /* ESSIV: struct crypto_cipher *essiv_tfm */
153 void *iv_private;
154 struct crypto_ablkcipher **tfms;
Milan Brozd1f96422011-01-13 19:59:54 +0000155 unsigned tfms_count;
Andi Kleenc0297722011-01-13 19:59:53 +0000156
157 /*
Milan Brozddd42ed2008-02-08 02:11:07 +0000158 * Layout of each crypto request:
159 *
160 * struct ablkcipher_request
161 * context
162 * padding
163 * struct dm_crypt_request
164 * padding
165 * IV
166 *
167 * The padding is added so that dm_crypt_request and the IV are
168 * correctly aligned.
169 */
170 unsigned int dmreq_start;
Milan Brozddd42ed2008-02-08 02:11:07 +0000171
Milan Broze48d4bb2006-10-03 01:15:37 -0700172 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 unsigned int key_size;
Milan Brozd1f96422011-01-13 19:59:54 +0000174 unsigned int key_parts;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 u8 key[0];
176};
177
Milan Broz6a24c712006-10-03 01:15:40 -0700178#define MIN_IOS 16
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179#define MIN_POOL_PAGES 32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
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{
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100197 return cc->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;
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100262 int err;
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
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100272 essiv_tfm = cc->iv_private;
Andi Kleenc0297722011-01-13 19:59:53 +0000273
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100274 err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
275 crypto_hash_digestsize(essiv->hash_tfm));
276 if (err)
277 return err;
Andi Kleenc0297722011-01-13 19:59:53 +0000278
279 return 0;
Milan Brozb95bf2d2009-12-10 23:51:56 +0000280}
281
Milan Broz542da312009-12-10 23:51:57 +0000282/* Wipe salt and reset key derived from volume key */
283static int crypt_iv_essiv_wipe(struct crypt_config *cc)
284{
285 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
286 unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
Andi Kleenc0297722011-01-13 19:59:53 +0000287 struct crypto_cipher *essiv_tfm;
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100288 int r, err = 0;
Milan Broz542da312009-12-10 23:51:57 +0000289
290 memset(essiv->salt, 0, salt_size);
291
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100292 essiv_tfm = cc->iv_private;
293 r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
294 if (r)
295 err = r;
Andi Kleenc0297722011-01-13 19:59:53 +0000296
297 return err;
298}
299
300/* Set up per cpu cipher state */
301static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
302 struct dm_target *ti,
303 u8 *salt, unsigned saltsize)
304{
305 struct crypto_cipher *essiv_tfm;
306 int err;
307
308 /* Setup the essiv_tfm with the given salt */
309 essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
310 if (IS_ERR(essiv_tfm)) {
311 ti->error = "Error allocating crypto tfm for ESSIV";
312 return essiv_tfm;
313 }
314
315 if (crypto_cipher_blocksize(essiv_tfm) !=
316 crypto_ablkcipher_ivsize(any_tfm(cc))) {
317 ti->error = "Block size of ESSIV cipher does "
318 "not match IV size of block cipher";
319 crypto_free_cipher(essiv_tfm);
320 return ERR_PTR(-EINVAL);
321 }
322
323 err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
324 if (err) {
325 ti->error = "Failed to set key for ESSIV cipher";
326 crypto_free_cipher(essiv_tfm);
327 return ERR_PTR(err);
328 }
329
330 return essiv_tfm;
Milan Broz542da312009-12-10 23:51:57 +0000331}
332
Milan Broz60473592009-12-10 23:51:55 +0000333static void crypt_iv_essiv_dtr(struct crypt_config *cc)
334{
Andi Kleenc0297722011-01-13 19:59:53 +0000335 struct crypto_cipher *essiv_tfm;
Milan Broz60473592009-12-10 23:51:55 +0000336 struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
337
Milan Brozb95bf2d2009-12-10 23:51:56 +0000338 crypto_free_hash(essiv->hash_tfm);
339 essiv->hash_tfm = NULL;
340
341 kzfree(essiv->salt);
342 essiv->salt = NULL;
Andi Kleenc0297722011-01-13 19:59:53 +0000343
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100344 essiv_tfm = cc->iv_private;
Andi Kleenc0297722011-01-13 19:59:53 +0000345
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100346 if (essiv_tfm)
347 crypto_free_cipher(essiv_tfm);
Andi Kleenc0297722011-01-13 19:59:53 +0000348
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100349 cc->iv_private = NULL;
Milan Broz60473592009-12-10 23:51:55 +0000350}
351
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
Milan Brozd469f842007-10-19 22:42:37 +0100353 const char *opts)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354{
Milan Broz5861f1b2009-12-10 23:51:56 +0000355 struct crypto_cipher *essiv_tfm = NULL;
356 struct crypto_hash *hash_tfm = NULL;
Milan Broz5861f1b2009-12-10 23:51:56 +0000357 u8 *salt = NULL;
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100358 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
Milan Broz5861f1b2009-12-10 23:51:56 +0000360 if (!opts) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700361 ti->error = "Digest algorithm missing for ESSIV mode";
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 return -EINVAL;
363 }
364
Milan Brozb95bf2d2009-12-10 23:51:56 +0000365 /* Allocate hash algorithm */
Herbert Xu35058682006-08-24 19:10:20 +1000366 hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC);
367 if (IS_ERR(hash_tfm)) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700368 ti->error = "Error initializing ESSIV hash";
Milan Broz5861f1b2009-12-10 23:51:56 +0000369 err = PTR_ERR(hash_tfm);
370 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 }
372
Milan Brozb95bf2d2009-12-10 23:51:56 +0000373 salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL);
Milan Broz5861f1b2009-12-10 23:51:56 +0000374 if (!salt) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -0700375 ti->error = "Error kmallocing salt storage in ESSIV";
Milan Broz5861f1b2009-12-10 23:51:56 +0000376 err = -ENOMEM;
377 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 }
379
Milan Brozb95bf2d2009-12-10 23:51:56 +0000380 cc->iv_gen_private.essiv.salt = salt;
Milan Brozb95bf2d2009-12-10 23:51:56 +0000381 cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
382
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100383 essiv_tfm = setup_essiv_cpu(cc, ti, salt,
384 crypto_hash_digestsize(hash_tfm));
385 if (IS_ERR(essiv_tfm)) {
386 crypt_iv_essiv_dtr(cc);
387 return PTR_ERR(essiv_tfm);
Andi Kleenc0297722011-01-13 19:59:53 +0000388 }
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100389 cc->iv_private = essiv_tfm;
Andi Kleenc0297722011-01-13 19:59:53 +0000390
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 return 0;
Milan Broz5861f1b2009-12-10 23:51:56 +0000392
393bad:
Milan Broz5861f1b2009-12-10 23:51:56 +0000394 if (hash_tfm && !IS_ERR(hash_tfm))
395 crypto_free_hash(hash_tfm);
Milan Brozb95bf2d2009-12-10 23:51:56 +0000396 kfree(salt);
Milan Broz5861f1b2009-12-10 23:51:56 +0000397 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398}
399
Milan Broz2dc53272011-01-13 19:59:54 +0000400static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
401 struct dm_crypt_request *dmreq)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402{
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100403 struct crypto_cipher *essiv_tfm = cc->iv_private;
Andi Kleenc0297722011-01-13 19:59:53 +0000404
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 memset(iv, 0, cc->iv_size);
Alasdair G Kergon283a8322011-08-02 12:32:01 +0100406 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
Andi Kleenc0297722011-01-13 19:59:53 +0000407 crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
408
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 return 0;
410}
411
Rik Snel48527fa2006-09-03 08:56:39 +1000412static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
413 const char *opts)
414{
Andi Kleenc0297722011-01-13 19:59:53 +0000415 unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
David Howellsf0d1b0b2006-12-08 02:37:49 -0800416 int log = ilog2(bs);
Rik Snel48527fa2006-09-03 08:56:39 +1000417
418 /* we need to calculate how far we must shift the sector count
419 * to get the cipher block count, we use this shift in _gen */
420
421 if (1 << log != bs) {
422 ti->error = "cypher blocksize is not a power of 2";
423 return -EINVAL;
424 }
425
426 if (log > 9) {
427 ti->error = "cypher blocksize is > 512";
428 return -EINVAL;
429 }
430
Milan Broz60473592009-12-10 23:51:55 +0000431 cc->iv_gen_private.benbi.shift = 9 - log;
Rik Snel48527fa2006-09-03 08:56:39 +1000432
433 return 0;
434}
435
436static void crypt_iv_benbi_dtr(struct crypt_config *cc)
437{
Rik Snel48527fa2006-09-03 08:56:39 +1000438}
439
Milan Broz2dc53272011-01-13 19:59:54 +0000440static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
441 struct dm_crypt_request *dmreq)
Rik Snel48527fa2006-09-03 08:56:39 +1000442{
Herbert Xu79066ad2006-12-05 13:41:52 -0800443 __be64 val;
444
Rik Snel48527fa2006-09-03 08:56:39 +1000445 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
Herbert Xu79066ad2006-12-05 13:41:52 -0800446
Milan Broz2dc53272011-01-13 19:59:54 +0000447 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
Herbert Xu79066ad2006-12-05 13:41:52 -0800448 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
Rik Snel48527fa2006-09-03 08:56:39 +1000449
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 return 0;
451}
452
Milan Broz2dc53272011-01-13 19:59:54 +0000453static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
454 struct dm_crypt_request *dmreq)
Ludwig Nussel46b47732007-05-09 02:32:55 -0700455{
456 memset(iv, 0, cc->iv_size);
457
458 return 0;
459}
460
Milan Broz34745782011-01-13 19:59:55 +0000461static void crypt_iv_lmk_dtr(struct crypt_config *cc)
462{
463 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
464
465 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
466 crypto_free_shash(lmk->hash_tfm);
467 lmk->hash_tfm = NULL;
468
469 kzfree(lmk->seed);
470 lmk->seed = NULL;
471}
472
473static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
474 const char *opts)
475{
476 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
477
478 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
479 if (IS_ERR(lmk->hash_tfm)) {
480 ti->error = "Error initializing LMK hash";
481 return PTR_ERR(lmk->hash_tfm);
482 }
483
484 /* No seed in LMK version 2 */
485 if (cc->key_parts == cc->tfms_count) {
486 lmk->seed = NULL;
487 return 0;
488 }
489
490 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
491 if (!lmk->seed) {
492 crypt_iv_lmk_dtr(cc);
493 ti->error = "Error kmallocing seed storage in LMK";
494 return -ENOMEM;
495 }
496
497 return 0;
498}
499
500static int crypt_iv_lmk_init(struct crypt_config *cc)
501{
502 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
503 int subkey_size = cc->key_size / cc->key_parts;
504
505 /* LMK seed is on the position of LMK_KEYS + 1 key */
506 if (lmk->seed)
507 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
508 crypto_shash_digestsize(lmk->hash_tfm));
509
510 return 0;
511}
512
513static int crypt_iv_lmk_wipe(struct crypt_config *cc)
514{
515 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
516
517 if (lmk->seed)
518 memset(lmk->seed, 0, LMK_SEED_SIZE);
519
520 return 0;
521}
522
523static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
524 struct dm_crypt_request *dmreq,
525 u8 *data)
526{
527 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
528 struct {
529 struct shash_desc desc;
530 char ctx[crypto_shash_descsize(lmk->hash_tfm)];
531 } sdesc;
532 struct md5_state md5state;
533 u32 buf[4];
534 int i, r;
535
536 sdesc.desc.tfm = lmk->hash_tfm;
537 sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
538
539 r = crypto_shash_init(&sdesc.desc);
540 if (r)
541 return r;
542
543 if (lmk->seed) {
544 r = crypto_shash_update(&sdesc.desc, lmk->seed, LMK_SEED_SIZE);
545 if (r)
546 return r;
547 }
548
549 /* Sector is always 512B, block size 16, add data of blocks 1-31 */
550 r = crypto_shash_update(&sdesc.desc, data + 16, 16 * 31);
551 if (r)
552 return r;
553
554 /* Sector is cropped to 56 bits here */
555 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
556 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
557 buf[2] = cpu_to_le32(4024);
558 buf[3] = 0;
559 r = crypto_shash_update(&sdesc.desc, (u8 *)buf, sizeof(buf));
560 if (r)
561 return r;
562
563 /* No MD5 padding here */
564 r = crypto_shash_export(&sdesc.desc, &md5state);
565 if (r)
566 return r;
567
568 for (i = 0; i < MD5_HASH_WORDS; i++)
569 __cpu_to_le32s(&md5state.hash[i]);
570 memcpy(iv, &md5state.hash, cc->iv_size);
571
572 return 0;
573}
574
575static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
576 struct dm_crypt_request *dmreq)
577{
578 u8 *src;
579 int r = 0;
580
581 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
Cong Wangc2e022c2011-11-28 13:26:02 +0800582 src = kmap_atomic(sg_page(&dmreq->sg_in));
Milan Broz34745782011-01-13 19:59:55 +0000583 r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset);
Cong Wangc2e022c2011-11-28 13:26:02 +0800584 kunmap_atomic(src);
Milan Broz34745782011-01-13 19:59:55 +0000585 } else
586 memset(iv, 0, cc->iv_size);
587
588 return r;
589}
590
591static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
592 struct dm_crypt_request *dmreq)
593{
594 u8 *dst;
595 int r;
596
597 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
598 return 0;
599
Cong Wangc2e022c2011-11-28 13:26:02 +0800600 dst = kmap_atomic(sg_page(&dmreq->sg_out));
Milan Broz34745782011-01-13 19:59:55 +0000601 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + dmreq->sg_out.offset);
602
603 /* Tweak the first block of plaintext sector */
604 if (!r)
605 crypto_xor(dst + dmreq->sg_out.offset, iv, cc->iv_size);
606
Cong Wangc2e022c2011-11-28 13:26:02 +0800607 kunmap_atomic(dst);
Milan Broz34745782011-01-13 19:59:55 +0000608 return r;
609}
610
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611static struct crypt_iv_operations crypt_iv_plain_ops = {
612 .generator = crypt_iv_plain_gen
613};
614
Milan Broz61afef62009-12-10 23:52:25 +0000615static struct crypt_iv_operations crypt_iv_plain64_ops = {
616 .generator = crypt_iv_plain64_gen
617};
618
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619static struct crypt_iv_operations crypt_iv_essiv_ops = {
620 .ctr = crypt_iv_essiv_ctr,
621 .dtr = crypt_iv_essiv_dtr,
Milan Brozb95bf2d2009-12-10 23:51:56 +0000622 .init = crypt_iv_essiv_init,
Milan Broz542da312009-12-10 23:51:57 +0000623 .wipe = crypt_iv_essiv_wipe,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 .generator = crypt_iv_essiv_gen
625};
626
Rik Snel48527fa2006-09-03 08:56:39 +1000627static struct crypt_iv_operations crypt_iv_benbi_ops = {
628 .ctr = crypt_iv_benbi_ctr,
629 .dtr = crypt_iv_benbi_dtr,
630 .generator = crypt_iv_benbi_gen
631};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632
Ludwig Nussel46b47732007-05-09 02:32:55 -0700633static struct crypt_iv_operations crypt_iv_null_ops = {
634 .generator = crypt_iv_null_gen
635};
636
Milan Broz34745782011-01-13 19:59:55 +0000637static struct crypt_iv_operations crypt_iv_lmk_ops = {
638 .ctr = crypt_iv_lmk_ctr,
639 .dtr = crypt_iv_lmk_dtr,
640 .init = crypt_iv_lmk_init,
641 .wipe = crypt_iv_lmk_wipe,
642 .generator = crypt_iv_lmk_gen,
643 .post = crypt_iv_lmk_post
644};
645
Milan Brozd469f842007-10-19 22:42:37 +0100646static void crypt_convert_init(struct crypt_config *cc,
647 struct convert_context *ctx,
648 struct bio *bio_out, struct bio *bio_in,
Milan Brozfcd369d2008-02-08 02:10:41 +0000649 sector_t sector)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650{
651 ctx->bio_in = bio_in;
652 ctx->bio_out = bio_out;
653 ctx->offset_in = 0;
654 ctx->offset_out = 0;
655 ctx->idx_in = bio_in ? bio_in->bi_idx : 0;
656 ctx->idx_out = bio_out ? bio_out->bi_idx : 0;
Mikulas Patockac66029f2012-07-27 15:08:05 +0100657 ctx->cc_sector = sector + cc->iv_offset;
Milan Broz43d69032008-02-08 02:11:09 +0000658 init_completion(&ctx->restart);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659}
660
Huang Yingb2174ee2009-03-16 17:44:33 +0000661static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
662 struct ablkcipher_request *req)
663{
664 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
665}
666
667static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
668 struct dm_crypt_request *dmreq)
669{
670 return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
671}
672
Milan Broz2dc53272011-01-13 19:59:54 +0000673static u8 *iv_of_dmreq(struct crypt_config *cc,
674 struct dm_crypt_request *dmreq)
675{
676 return (u8 *)ALIGN((unsigned long)(dmreq + 1),
677 crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
678}
679
Milan Broz01482b72008-02-08 02:11:04 +0000680static int crypt_convert_block(struct crypt_config *cc,
Milan Broz3a7f6c92008-02-08 02:11:14 +0000681 struct convert_context *ctx,
682 struct ablkcipher_request *req)
Milan Broz01482b72008-02-08 02:11:04 +0000683{
684 struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in);
685 struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000686 struct dm_crypt_request *dmreq;
687 u8 *iv;
Mikulas Patocka40b62292012-07-27 15:08:04 +0100688 int r;
Milan Broz01482b72008-02-08 02:11:04 +0000689
Huang Yingb2174ee2009-03-16 17:44:33 +0000690 dmreq = dmreq_of_req(cc, req);
Milan Broz2dc53272011-01-13 19:59:54 +0000691 iv = iv_of_dmreq(cc, dmreq);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000692
Mikulas Patockac66029f2012-07-27 15:08:05 +0100693 dmreq->iv_sector = ctx->cc_sector;
Huang Yingb2174ee2009-03-16 17:44:33 +0000694 dmreq->ctx = ctx;
Milan Broz3a7f6c92008-02-08 02:11:14 +0000695 sg_init_table(&dmreq->sg_in, 1);
696 sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
Milan Broz01482b72008-02-08 02:11:04 +0000697 bv_in->bv_offset + ctx->offset_in);
698
Milan Broz3a7f6c92008-02-08 02:11:14 +0000699 sg_init_table(&dmreq->sg_out, 1);
700 sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT,
Milan Broz01482b72008-02-08 02:11:04 +0000701 bv_out->bv_offset + ctx->offset_out);
702
703 ctx->offset_in += 1 << SECTOR_SHIFT;
704 if (ctx->offset_in >= bv_in->bv_len) {
705 ctx->offset_in = 0;
706 ctx->idx_in++;
707 }
708
709 ctx->offset_out += 1 << SECTOR_SHIFT;
710 if (ctx->offset_out >= bv_out->bv_len) {
711 ctx->offset_out = 0;
712 ctx->idx_out++;
713 }
714
Milan Broz3a7f6c92008-02-08 02:11:14 +0000715 if (cc->iv_gen_ops) {
Milan Broz2dc53272011-01-13 19:59:54 +0000716 r = cc->iv_gen_ops->generator(cc, iv, dmreq);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000717 if (r < 0)
718 return r;
719 }
720
721 ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out,
722 1 << SECTOR_SHIFT, iv);
723
724 if (bio_data_dir(ctx->bio_in) == WRITE)
725 r = crypto_ablkcipher_encrypt(req);
726 else
727 r = crypto_ablkcipher_decrypt(req);
728
Milan Broz2dc53272011-01-13 19:59:54 +0000729 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
730 r = cc->iv_gen_ops->post(cc, iv, dmreq);
731
Milan Broz3a7f6c92008-02-08 02:11:14 +0000732 return r;
Milan Broz01482b72008-02-08 02:11:04 +0000733}
734
Milan Broz95497a92008-02-08 02:11:12 +0000735static void kcryptd_async_done(struct crypto_async_request *async_req,
736 int error);
Andi Kleenc0297722011-01-13 19:59:53 +0000737
Milan Brozddd42ed2008-02-08 02:11:07 +0000738static void crypt_alloc_req(struct crypt_config *cc,
739 struct convert_context *ctx)
740{
Andi Kleenc0297722011-01-13 19:59:53 +0000741 struct crypt_cpu *this_cc = this_crypt_config(cc);
Mikulas Patockac66029f2012-07-27 15:08:05 +0100742 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
Andi Kleenc0297722011-01-13 19:59:53 +0000743
744 if (!this_cc->req)
745 this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
746
Mikulas Patockafd2d2312012-07-27 15:08:05 +0100747 ablkcipher_request_set_tfm(this_cc->req, cc->tfms[key_index]);
Andi Kleenc0297722011-01-13 19:59:53 +0000748 ablkcipher_request_set_callback(this_cc->req,
749 CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
750 kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
Milan Brozddd42ed2008-02-08 02:11:07 +0000751}
752
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753/*
754 * Encrypt / decrypt data from one bio to another one (can be the same one)
755 */
756static int crypt_convert(struct crypt_config *cc,
Milan Brozd469f842007-10-19 22:42:37 +0100757 struct convert_context *ctx)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758{
Andi Kleenc0297722011-01-13 19:59:53 +0000759 struct crypt_cpu *this_cc = this_crypt_config(cc);
Milan Broz3f1e9072008-03-28 14:16:07 -0700760 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761
Mikulas Patocka40b62292012-07-27 15:08:04 +0100762 atomic_set(&ctx->cc_pending, 1);
Milan Brozc8081612008-10-10 13:37:08 +0100763
Linus Torvalds1da177e2005-04-16 15:20:36 -0700764 while(ctx->idx_in < ctx->bio_in->bi_vcnt &&
765 ctx->idx_out < ctx->bio_out->bi_vcnt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766
Milan Broz3a7f6c92008-02-08 02:11:14 +0000767 crypt_alloc_req(cc, ctx);
768
Mikulas Patocka40b62292012-07-27 15:08:04 +0100769 atomic_inc(&ctx->cc_pending);
Milan Broz3f1e9072008-03-28 14:16:07 -0700770
Andi Kleenc0297722011-01-13 19:59:53 +0000771 r = crypt_convert_block(cc, ctx, this_cc->req);
Milan Broz3a7f6c92008-02-08 02:11:14 +0000772
773 switch (r) {
Milan Broz3f1e9072008-03-28 14:16:07 -0700774 /* async */
Milan Broz3a7f6c92008-02-08 02:11:14 +0000775 case -EBUSY:
776 wait_for_completion(&ctx->restart);
777 INIT_COMPLETION(ctx->restart);
778 /* fall through*/
779 case -EINPROGRESS:
Andi Kleenc0297722011-01-13 19:59:53 +0000780 this_cc->req = NULL;
Mikulas Patockac66029f2012-07-27 15:08:05 +0100781 ctx->cc_sector++;
Milan Broz3a7f6c92008-02-08 02:11:14 +0000782 continue;
Milan Broz3a7f6c92008-02-08 02:11:14 +0000783
Milan Broz3f1e9072008-03-28 14:16:07 -0700784 /* sync */
785 case 0:
Mikulas Patocka40b62292012-07-27 15:08:04 +0100786 atomic_dec(&ctx->cc_pending);
Mikulas Patockac66029f2012-07-27 15:08:05 +0100787 ctx->cc_sector++;
Milan Brozc7f1b202008-07-02 09:34:28 +0100788 cond_resched();
Milan Broz3f1e9072008-03-28 14:16:07 -0700789 continue;
790
791 /* error */
792 default:
Mikulas Patocka40b62292012-07-27 15:08:04 +0100793 atomic_dec(&ctx->cc_pending);
Milan Broz3f1e9072008-03-28 14:16:07 -0700794 return r;
795 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 }
797
Milan Broz3f1e9072008-03-28 14:16:07 -0700798 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799}
800
801/*
802 * Generate a new unfragmented bio with the given size
803 * This should never violate the device limitations
Milan Broz933f01d2008-10-10 13:37:08 +0100804 * May return a smaller bio when running out of pages, indicated by
805 * *out_of_pages set to 1.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806 */
Milan Broz933f01d2008-10-10 13:37:08 +0100807static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size,
808 unsigned *out_of_pages)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100810 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -0700811 struct bio *clone;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
Al Virob4e3ca12005-10-21 03:22:34 -0400813 gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM;
Milan Broz91e10622007-12-13 14:16:10 +0000814 unsigned i, len;
815 struct page *page;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816
Olaf Kirch2f9941b2007-05-09 02:32:53 -0700817 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs);
Milan Broz8b004452006-10-03 01:15:37 -0700818 if (!clone)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820
Olaf Kirch027581f2007-05-09 02:32:52 -0700821 clone_init(io, clone);
Milan Broz933f01d2008-10-10 13:37:08 +0100822 *out_of_pages = 0;
Milan Broz6a24c712006-10-03 01:15:40 -0700823
Olaf Kirchf97380b2007-05-09 02:32:54 -0700824 for (i = 0; i < nr_iovecs; i++) {
Milan Broz91e10622007-12-13 14:16:10 +0000825 page = mempool_alloc(cc->page_pool, gfp_mask);
Milan Broz933f01d2008-10-10 13:37:08 +0100826 if (!page) {
827 *out_of_pages = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 break;
Milan Broz933f01d2008-10-10 13:37:08 +0100829 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830
831 /*
Mikulas Patockaaeb2dea2012-03-28 18:41:22 +0100832 * If additional pages cannot be allocated without waiting,
833 * return a partially-allocated bio. The caller will then try
834 * to allocate more bios while submitting this partial bio.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 */
Mikulas Patockaaeb2dea2012-03-28 18:41:22 +0100836 gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837
Milan Broz91e10622007-12-13 14:16:10 +0000838 len = (size > PAGE_SIZE) ? PAGE_SIZE : size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839
Milan Broz91e10622007-12-13 14:16:10 +0000840 if (!bio_add_page(clone, page, len, 0)) {
841 mempool_free(page, cc->page_pool);
842 break;
843 }
844
845 size -= len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 }
847
Milan Broz8b004452006-10-03 01:15:37 -0700848 if (!clone->bi_size) {
849 bio_put(clone);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700850 return NULL;
851 }
852
Milan Broz8b004452006-10-03 01:15:37 -0700853 return clone;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854}
855
Neil Brown644bd2f2007-10-16 13:48:46 +0200856static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857{
Neil Brown644bd2f2007-10-16 13:48:46 +0200858 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 struct bio_vec *bv;
860
Kent Overstreetcb34e052012-09-05 15:22:02 -0700861 bio_for_each_segment_all(bv, clone, i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 BUG_ON(!bv->bv_page);
863 mempool_free(bv->bv_page, cc->page_pool);
864 bv->bv_page = NULL;
865 }
866}
867
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100868static struct dm_crypt_io *crypt_io_alloc(struct crypt_config *cc,
Milan Brozdc440d1e2008-10-10 13:37:03 +0100869 struct bio *bio, sector_t sector)
870{
Milan Brozdc440d1e2008-10-10 13:37:03 +0100871 struct dm_crypt_io *io;
872
873 io = mempool_alloc(cc->io_pool, GFP_NOIO);
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100874 io->cc = cc;
Milan Brozdc440d1e2008-10-10 13:37:03 +0100875 io->base_bio = bio;
876 io->sector = sector;
877 io->error = 0;
Milan Broz393b47e2008-10-21 17:45:02 +0100878 io->base_io = NULL;
Mikulas Patocka40b62292012-07-27 15:08:04 +0100879 atomic_set(&io->io_pending, 0);
Milan Brozdc440d1e2008-10-10 13:37:03 +0100880
881 return io;
882}
883
Milan Broz3e1a8bd2008-10-10 13:37:02 +0100884static void crypt_inc_pending(struct dm_crypt_io *io)
885{
Mikulas Patocka40b62292012-07-27 15:08:04 +0100886 atomic_inc(&io->io_pending);
Milan Broz3e1a8bd2008-10-10 13:37:02 +0100887}
888
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889/*
890 * One of the bios was finished. Check for completion of
891 * the whole request and correctly clean up the buffer.
Milan Broz393b47e2008-10-21 17:45:02 +0100892 * If base_io is set, wait for the last fragment to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 */
Milan Broz5742fd72008-02-08 02:10:43 +0000894static void crypt_dec_pending(struct dm_crypt_io *io)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100896 struct crypt_config *cc = io->cc;
Milan Brozb35f8ca2009-03-16 17:44:36 +0000897 struct bio *base_bio = io->base_bio;
898 struct dm_crypt_io *base_io = io->base_io;
899 int error = io->error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900
Mikulas Patocka40b62292012-07-27 15:08:04 +0100901 if (!atomic_dec_and_test(&io->io_pending))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700902 return;
903
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 mempool_free(io, cc->io_pool);
Milan Brozb35f8ca2009-03-16 17:44:36 +0000905
906 if (likely(!base_io))
907 bio_endio(base_bio, error);
908 else {
909 if (error && !base_io->error)
910 base_io->error = error;
911 crypt_dec_pending(base_io);
912 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913}
914
915/*
Milan Brozcabf08e2007-10-19 22:38:58 +0100916 * kcryptd/kcryptd_io:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917 *
918 * Needed because it would be very unwise to do decryption in an
Milan Broz23541d22006-10-03 01:15:39 -0700919 * interrupt context.
Milan Brozcabf08e2007-10-19 22:38:58 +0100920 *
921 * kcryptd performs the actual encryption or decryption.
922 *
923 * kcryptd_io performs the IO submission.
924 *
925 * They must be separated as otherwise the final stages could be
926 * starved by new requests which can block in the first stages due
927 * to memory allocation.
Andi Kleenc0297722011-01-13 19:59:53 +0000928 *
929 * The work is done per CPU global for all dm-crypt instances.
930 * They should not depend on each other and do not block.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 */
NeilBrown6712ecf2007-09-27 12:47:43 +0200932static void crypt_endio(struct bio *clone, int error)
Milan Broz8b004452006-10-03 01:15:37 -0700933{
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100934 struct dm_crypt_io *io = clone->bi_private;
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100935 struct crypt_config *cc = io->cc;
Milan Brozee7a4912008-02-08 02:10:46 +0000936 unsigned rw = bio_data_dir(clone);
Milan Broz8b004452006-10-03 01:15:37 -0700937
Milan Brozadfe4772007-12-13 14:15:51 +0000938 if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error))
939 error = -EIO;
940
Milan Broz8b004452006-10-03 01:15:37 -0700941 /*
NeilBrown6712ecf2007-09-27 12:47:43 +0200942 * free the processed pages
Milan Broz8b004452006-10-03 01:15:37 -0700943 */
Milan Brozee7a4912008-02-08 02:10:46 +0000944 if (rw == WRITE)
Neil Brown644bd2f2007-10-16 13:48:46 +0200945 crypt_free_buffer_pages(cc, clone);
Milan Brozee7a4912008-02-08 02:10:46 +0000946
947 bio_put(clone);
948
949 if (rw == READ && !error) {
950 kcryptd_queue_crypt(io);
951 return;
NeilBrown6712ecf2007-09-27 12:47:43 +0200952 }
Milan Broz8b004452006-10-03 01:15:37 -0700953
Milan Brozadfe4772007-12-13 14:15:51 +0000954 if (unlikely(error))
Milan Broz5742fd72008-02-08 02:10:43 +0000955 io->error = error;
956
957 crypt_dec_pending(io);
Milan Broz8b004452006-10-03 01:15:37 -0700958}
959
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100960static void clone_init(struct dm_crypt_io *io, struct bio *clone)
Milan Broz8b004452006-10-03 01:15:37 -0700961{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100962 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -0700963
964 clone->bi_private = io;
965 clone->bi_end_io = crypt_endio;
966 clone->bi_bdev = cc->dev->bdev;
967 clone->bi_rw = io->base_bio->bi_rw;
968}
969
Milan Broz20c82532011-01-13 19:59:53 +0000970static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
Milan Broz8b004452006-10-03 01:15:37 -0700971{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100972 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -0700973 struct bio *base_bio = io->base_bio;
974 struct bio *clone;
Milan Broz93e605c2006-10-03 01:15:38 -0700975
Milan Broz8b004452006-10-03 01:15:37 -0700976 /*
977 * The block layer might modify the bvec array, so always
978 * copy the required bvecs because we need the original
979 * one in order to decrypt the whole bio data *afterwards*.
980 */
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700981 clone = bio_clone_bioset(base_bio, gfp, cc->bs);
Jens Axboe7eaceac2011-03-10 08:52:07 +0100982 if (!clone)
Milan Broz20c82532011-01-13 19:59:53 +0000983 return 1;
Milan Broz8b004452006-10-03 01:15:37 -0700984
Milan Broz20c82532011-01-13 19:59:53 +0000985 crypt_inc_pending(io);
986
Milan Broz8b004452006-10-03 01:15:37 -0700987 clone_init(io, clone);
Milan Broz0c395b02008-02-08 02:10:54 +0000988 clone->bi_sector = cc->start + io->sector;
Milan Broz8b004452006-10-03 01:15:37 -0700989
Milan Broz93e605c2006-10-03 01:15:38 -0700990 generic_make_request(clone);
Milan Broz20c82532011-01-13 19:59:53 +0000991 return 0;
Milan Broz8b004452006-10-03 01:15:37 -0700992}
993
Milan Broz4e4eef62008-02-08 02:10:49 +0000994static void kcryptd_io_write(struct dm_crypt_io *io)
995{
Milan Broz95497a92008-02-08 02:11:12 +0000996 struct bio *clone = io->ctx.bio_out;
Milan Broz95497a92008-02-08 02:11:12 +0000997 generic_make_request(clone);
Milan Broz4e4eef62008-02-08 02:10:49 +0000998}
999
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001000static void kcryptd_io(struct work_struct *work)
1001{
1002 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1003
Milan Broz20c82532011-01-13 19:59:53 +00001004 if (bio_data_dir(io->base_bio) == READ) {
1005 crypt_inc_pending(io);
1006 if (kcryptd_io_read(io, GFP_NOIO))
1007 io->error = -ENOMEM;
1008 crypt_dec_pending(io);
1009 } else
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001010 kcryptd_io_write(io);
1011}
1012
1013static void kcryptd_queue_io(struct dm_crypt_io *io)
1014{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001015 struct crypt_config *cc = io->cc;
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001016
1017 INIT_WORK(&io->work, kcryptd_io);
1018 queue_work(cc->io_queue, &io->work);
1019}
1020
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001021static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
Milan Broz4e4eef62008-02-08 02:10:49 +00001022{
Milan Brozdec1ced2008-02-08 02:10:57 +00001023 struct bio *clone = io->ctx.bio_out;
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001024 struct crypt_config *cc = io->cc;
Milan Brozdec1ced2008-02-08 02:10:57 +00001025
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001026 if (unlikely(io->error < 0)) {
Milan Brozdec1ced2008-02-08 02:10:57 +00001027 crypt_free_buffer_pages(cc, clone);
1028 bio_put(clone);
Milan Broz6c031f42008-10-10 13:37:06 +01001029 crypt_dec_pending(io);
Milan Brozdec1ced2008-02-08 02:10:57 +00001030 return;
1031 }
1032
1033 /* crypt_convert should have filled the clone bio */
1034 BUG_ON(io->ctx.idx_out < clone->bi_vcnt);
1035
1036 clone->bi_sector = cc->start + io->sector;
Milan Broz899c95d2008-02-08 02:11:02 +00001037
Milan Broz95497a92008-02-08 02:11:12 +00001038 if (async)
1039 kcryptd_queue_io(io);
Alasdair G Kergon1e37bb82008-10-10 13:37:05 +01001040 else
Milan Broz95497a92008-02-08 02:11:12 +00001041 generic_make_request(clone);
Milan Broz4e4eef62008-02-08 02:10:49 +00001042}
1043
Milan Brozfc5a5e92008-10-10 13:37:04 +01001044static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
Milan Broz8b004452006-10-03 01:15:37 -07001045{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001046 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -07001047 struct bio *clone;
Milan Broz393b47e2008-10-21 17:45:02 +01001048 struct dm_crypt_io *new_io;
Milan Brozc8081612008-10-10 13:37:08 +01001049 int crypt_finished;
Milan Broz933f01d2008-10-10 13:37:08 +01001050 unsigned out_of_pages = 0;
Milan Brozdec1ced2008-02-08 02:10:57 +00001051 unsigned remaining = io->base_bio->bi_size;
Milan Brozb635b002008-10-21 17:45:00 +01001052 sector_t sector = io->sector;
Milan Brozdec1ced2008-02-08 02:10:57 +00001053 int r;
Milan Broz8b004452006-10-03 01:15:37 -07001054
Milan Broz93e605c2006-10-03 01:15:38 -07001055 /*
Milan Brozfc5a5e92008-10-10 13:37:04 +01001056 * Prevent io from disappearing until this function completes.
1057 */
1058 crypt_inc_pending(io);
Milan Brozb635b002008-10-21 17:45:00 +01001059 crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
Milan Brozfc5a5e92008-10-10 13:37:04 +01001060
1061 /*
Milan Broz93e605c2006-10-03 01:15:38 -07001062 * The allocated buffers can be smaller than the whole bio,
1063 * so repeat the whole process until all the data can be handled.
1064 */
1065 while (remaining) {
Milan Broz933f01d2008-10-10 13:37:08 +01001066 clone = crypt_alloc_buffer(io, remaining, &out_of_pages);
Milan Broz23541d22006-10-03 01:15:39 -07001067 if (unlikely(!clone)) {
Milan Broz5742fd72008-02-08 02:10:43 +00001068 io->error = -ENOMEM;
Milan Brozfc5a5e92008-10-10 13:37:04 +01001069 break;
Milan Broz23541d22006-10-03 01:15:39 -07001070 }
Milan Broz93e605c2006-10-03 01:15:38 -07001071
Milan Broz53017032008-02-08 02:10:38 +00001072 io->ctx.bio_out = clone;
1073 io->ctx.idx_out = 0;
Milan Broz93e605c2006-10-03 01:15:38 -07001074
Milan Broz93e605c2006-10-03 01:15:38 -07001075 remaining -= clone->bi_size;
Milan Brozb635b002008-10-21 17:45:00 +01001076 sector += bio_sectors(clone);
Milan Brozdec1ced2008-02-08 02:10:57 +00001077
Milan Broz4e594092008-10-10 13:37:07 +01001078 crypt_inc_pending(io);
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001079
Milan Brozdec1ced2008-02-08 02:10:57 +00001080 r = crypt_convert(cc, &io->ctx);
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001081 if (r < 0)
1082 io->error = -EIO;
1083
Mikulas Patocka40b62292012-07-27 15:08:04 +01001084 crypt_finished = atomic_dec_and_test(&io->ctx.cc_pending);
Milan Brozdec1ced2008-02-08 02:10:57 +00001085
Milan Brozc8081612008-10-10 13:37:08 +01001086 /* Encryption was already finished, submit io now */
1087 if (crypt_finished) {
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001088 kcryptd_crypt_write_io_submit(io, 0);
Milan Brozc8081612008-10-10 13:37:08 +01001089
1090 /*
1091 * If there was an error, do not try next fragments.
1092 * For async, error is processed in async handler.
1093 */
Milan Broz6c031f42008-10-10 13:37:06 +01001094 if (unlikely(r < 0))
Milan Brozfc5a5e92008-10-10 13:37:04 +01001095 break;
Milan Brozb635b002008-10-21 17:45:00 +01001096
1097 io->sector = sector;
Milan Broz4e594092008-10-10 13:37:07 +01001098 }
Milan Broz93e605c2006-10-03 01:15:38 -07001099
Milan Broz933f01d2008-10-10 13:37:08 +01001100 /*
1101 * Out of memory -> run queues
1102 * But don't wait if split was due to the io size restriction
1103 */
1104 if (unlikely(out_of_pages))
Jens Axboe8aa7e842009-07-09 14:52:32 +02001105 congestion_wait(BLK_RW_ASYNC, HZ/100);
Milan Broz933f01d2008-10-10 13:37:08 +01001106
Milan Broz393b47e2008-10-21 17:45:02 +01001107 /*
1108 * With async crypto it is unsafe to share the crypto context
1109 * between fragments, so switch to a new dm_crypt_io structure.
1110 */
1111 if (unlikely(!crypt_finished && remaining)) {
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001112 new_io = crypt_io_alloc(io->cc, io->base_bio,
Milan Broz393b47e2008-10-21 17:45:02 +01001113 sector);
1114 crypt_inc_pending(new_io);
1115 crypt_convert_init(cc, &new_io->ctx, NULL,
1116 io->base_bio, sector);
1117 new_io->ctx.idx_in = io->ctx.idx_in;
1118 new_io->ctx.offset_in = io->ctx.offset_in;
1119
1120 /*
1121 * Fragments after the first use the base_io
1122 * pending count.
1123 */
1124 if (!io->base_io)
1125 new_io->base_io = io;
1126 else {
1127 new_io->base_io = io->base_io;
1128 crypt_inc_pending(io->base_io);
1129 crypt_dec_pending(io);
1130 }
1131
1132 io = new_io;
1133 }
Milan Broz8b004452006-10-03 01:15:37 -07001134 }
Milan Broz899c95d2008-02-08 02:11:02 +00001135
1136 crypt_dec_pending(io);
Milan Broz84131db2008-02-08 02:10:59 +00001137}
1138
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001139static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
Milan Broz5742fd72008-02-08 02:10:43 +00001140{
Milan Broz5742fd72008-02-08 02:10:43 +00001141 crypt_dec_pending(io);
1142}
1143
Milan Broz4e4eef62008-02-08 02:10:49 +00001144static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
Milan Broz8b004452006-10-03 01:15:37 -07001145{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001146 struct crypt_config *cc = io->cc;
Milan Broz5742fd72008-02-08 02:10:43 +00001147 int r = 0;
Milan Broz8b004452006-10-03 01:15:37 -07001148
Milan Broz3e1a8bd2008-10-10 13:37:02 +01001149 crypt_inc_pending(io);
Milan Broz3a7f6c92008-02-08 02:11:14 +00001150
Milan Broz53017032008-02-08 02:10:38 +00001151 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
Milan Broz0c395b02008-02-08 02:10:54 +00001152 io->sector);
Milan Broz8b004452006-10-03 01:15:37 -07001153
Milan Broz5742fd72008-02-08 02:10:43 +00001154 r = crypt_convert(cc, &io->ctx);
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001155 if (r < 0)
1156 io->error = -EIO;
Milan Broz5742fd72008-02-08 02:10:43 +00001157
Mikulas Patocka40b62292012-07-27 15:08:04 +01001158 if (atomic_dec_and_test(&io->ctx.cc_pending))
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001159 kcryptd_crypt_read_done(io);
Milan Broz3a7f6c92008-02-08 02:11:14 +00001160
1161 crypt_dec_pending(io);
Milan Broz8b004452006-10-03 01:15:37 -07001162}
1163
Milan Broz95497a92008-02-08 02:11:12 +00001164static void kcryptd_async_done(struct crypto_async_request *async_req,
1165 int error)
1166{
Huang Yingb2174ee2009-03-16 17:44:33 +00001167 struct dm_crypt_request *dmreq = async_req->data;
1168 struct convert_context *ctx = dmreq->ctx;
Milan Broz95497a92008-02-08 02:11:12 +00001169 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001170 struct crypt_config *cc = io->cc;
Milan Broz95497a92008-02-08 02:11:12 +00001171
1172 if (error == -EINPROGRESS) {
1173 complete(&ctx->restart);
1174 return;
1175 }
1176
Milan Broz2dc53272011-01-13 19:59:54 +00001177 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
1178 error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq);
1179
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001180 if (error < 0)
1181 io->error = -EIO;
1182
Huang Yingb2174ee2009-03-16 17:44:33 +00001183 mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
Milan Broz95497a92008-02-08 02:11:12 +00001184
Mikulas Patocka40b62292012-07-27 15:08:04 +01001185 if (!atomic_dec_and_test(&ctx->cc_pending))
Milan Broz95497a92008-02-08 02:11:12 +00001186 return;
1187
1188 if (bio_data_dir(io->base_bio) == READ)
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001189 kcryptd_crypt_read_done(io);
Milan Broz95497a92008-02-08 02:11:12 +00001190 else
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001191 kcryptd_crypt_write_io_submit(io, 1);
Milan Broz95497a92008-02-08 02:11:12 +00001192}
1193
Milan Broz4e4eef62008-02-08 02:10:49 +00001194static void kcryptd_crypt(struct work_struct *work)
1195{
1196 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1197
1198 if (bio_data_dir(io->base_bio) == READ)
1199 kcryptd_crypt_read_convert(io);
1200 else
1201 kcryptd_crypt_write_convert(io);
Milan Broz8b004452006-10-03 01:15:37 -07001202}
1203
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001204static void kcryptd_queue_crypt(struct dm_crypt_io *io)
1205{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001206 struct crypt_config *cc = io->cc;
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001207
1208 INIT_WORK(&io->work, kcryptd_crypt);
1209 queue_work(cc->crypt_queue, &io->work);
1210}
1211
Linus Torvalds1da177e2005-04-16 15:20:36 -07001212/*
1213 * Decode key from its hex representation
1214 */
1215static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
1216{
1217 char buffer[3];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001218 unsigned int i;
1219
1220 buffer[2] = '\0';
1221
Milan Broz8b004452006-10-03 01:15:37 -07001222 for (i = 0; i < size; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223 buffer[0] = *hex++;
1224 buffer[1] = *hex++;
1225
majianpeng1a66a082012-07-27 15:07:59 +01001226 if (kstrtou8(buffer, 16, &key[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227 return -EINVAL;
1228 }
1229
1230 if (*hex != '\0')
1231 return -EINVAL;
1232
1233 return 0;
1234}
1235
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001236static void crypt_free_tfms(struct crypt_config *cc)
Milan Brozd1f96422011-01-13 19:59:54 +00001237{
Milan Brozd1f96422011-01-13 19:59:54 +00001238 unsigned i;
1239
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001240 if (!cc->tfms)
1241 return;
1242
Milan Brozd1f96422011-01-13 19:59:54 +00001243 for (i = 0; i < cc->tfms_count; i++)
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001244 if (cc->tfms[i] && !IS_ERR(cc->tfms[i])) {
1245 crypto_free_ablkcipher(cc->tfms[i]);
1246 cc->tfms[i] = NULL;
Milan Brozd1f96422011-01-13 19:59:54 +00001247 }
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001248
1249 kfree(cc->tfms);
1250 cc->tfms = NULL;
Milan Brozd1f96422011-01-13 19:59:54 +00001251}
1252
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001253static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
Milan Brozd1f96422011-01-13 19:59:54 +00001254{
Milan Brozd1f96422011-01-13 19:59:54 +00001255 unsigned i;
1256 int err;
1257
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001258 cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_ablkcipher *),
1259 GFP_KERNEL);
1260 if (!cc->tfms)
1261 return -ENOMEM;
1262
Milan Brozd1f96422011-01-13 19:59:54 +00001263 for (i = 0; i < cc->tfms_count; i++) {
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001264 cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
1265 if (IS_ERR(cc->tfms[i])) {
1266 err = PTR_ERR(cc->tfms[i]);
1267 crypt_free_tfms(cc);
Milan Brozd1f96422011-01-13 19:59:54 +00001268 return err;
1269 }
1270 }
1271
1272 return 0;
1273}
1274
Andi Kleenc0297722011-01-13 19:59:53 +00001275static int crypt_setkey_allcpus(struct crypt_config *cc)
1276{
Milan Brozd1f96422011-01-13 19:59:54 +00001277 unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count);
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001278 int err = 0, i, r;
Andi Kleenc0297722011-01-13 19:59:53 +00001279
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001280 for (i = 0; i < cc->tfms_count; i++) {
1281 r = crypto_ablkcipher_setkey(cc->tfms[i],
1282 cc->key + (i * subkey_size),
1283 subkey_size);
1284 if (r)
1285 err = r;
Andi Kleenc0297722011-01-13 19:59:53 +00001286 }
1287
1288 return err;
1289}
1290
Milan Broze48d4bb2006-10-03 01:15:37 -07001291static int crypt_set_key(struct crypt_config *cc, char *key)
1292{
Milan Brozde8be5a2011-03-24 13:54:27 +00001293 int r = -EINVAL;
1294 int key_string_len = strlen(key);
1295
Milan Broz69a8cfc2011-01-13 19:59:49 +00001296 /* The key size may not be changed. */
Milan Brozde8be5a2011-03-24 13:54:27 +00001297 if (cc->key_size != (key_string_len >> 1))
1298 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001299
Milan Broz69a8cfc2011-01-13 19:59:49 +00001300 /* Hyphen (which gives a key_size of zero) means there is no key. */
1301 if (!cc->key_size && strcmp(key, "-"))
Milan Brozde8be5a2011-03-24 13:54:27 +00001302 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001303
Milan Broz69a8cfc2011-01-13 19:59:49 +00001304 if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
Milan Brozde8be5a2011-03-24 13:54:27 +00001305 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001306
1307 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1308
Milan Brozde8be5a2011-03-24 13:54:27 +00001309 r = crypt_setkey_allcpus(cc);
1310
1311out:
1312 /* Hex key string not needed after here, so wipe it. */
1313 memset(key, '0', key_string_len);
1314
1315 return r;
Milan Broze48d4bb2006-10-03 01:15:37 -07001316}
1317
1318static int crypt_wipe_key(struct crypt_config *cc)
1319{
1320 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1321 memset(&cc->key, 0, cc->key_size * sizeof(u8));
Andi Kleenc0297722011-01-13 19:59:53 +00001322
1323 return crypt_setkey_allcpus(cc);
Milan Broze48d4bb2006-10-03 01:15:37 -07001324}
1325
Milan Broz28513fc2010-08-12 04:14:06 +01001326static void crypt_dtr(struct dm_target *ti)
1327{
1328 struct crypt_config *cc = ti->private;
Andi Kleenc0297722011-01-13 19:59:53 +00001329 struct crypt_cpu *cpu_cc;
1330 int cpu;
Milan Broz28513fc2010-08-12 04:14:06 +01001331
1332 ti->private = NULL;
1333
1334 if (!cc)
1335 return;
1336
1337 if (cc->io_queue)
1338 destroy_workqueue(cc->io_queue);
1339 if (cc->crypt_queue)
1340 destroy_workqueue(cc->crypt_queue);
1341
Andi Kleenc0297722011-01-13 19:59:53 +00001342 if (cc->cpu)
1343 for_each_possible_cpu(cpu) {
1344 cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1345 if (cpu_cc->req)
1346 mempool_free(cpu_cc->req, cc->req_pool);
Andi Kleenc0297722011-01-13 19:59:53 +00001347 }
1348
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001349 crypt_free_tfms(cc);
1350
Milan Broz28513fc2010-08-12 04:14:06 +01001351 if (cc->bs)
1352 bioset_free(cc->bs);
1353
1354 if (cc->page_pool)
1355 mempool_destroy(cc->page_pool);
1356 if (cc->req_pool)
1357 mempool_destroy(cc->req_pool);
1358 if (cc->io_pool)
1359 mempool_destroy(cc->io_pool);
1360
1361 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
1362 cc->iv_gen_ops->dtr(cc);
1363
Milan Broz28513fc2010-08-12 04:14:06 +01001364 if (cc->dev)
1365 dm_put_device(ti, cc->dev);
1366
Andi Kleenc0297722011-01-13 19:59:53 +00001367 if (cc->cpu)
1368 free_percpu(cc->cpu);
1369
Milan Broz5ebaee62010-08-12 04:14:07 +01001370 kzfree(cc->cipher);
Milan Broz7dbcd132011-01-13 19:59:52 +00001371 kzfree(cc->cipher_string);
Milan Broz28513fc2010-08-12 04:14:06 +01001372
1373 /* Must zero key material before freeing */
1374 kzfree(cc);
1375}
1376
Milan Broz5ebaee62010-08-12 04:14:07 +01001377static int crypt_ctr_cipher(struct dm_target *ti,
1378 char *cipher_in, char *key)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379{
Milan Broz5ebaee62010-08-12 04:14:07 +01001380 struct crypt_config *cc = ti->private;
Milan Brozd1f96422011-01-13 19:59:54 +00001381 char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
Milan Broz5ebaee62010-08-12 04:14:07 +01001382 char *cipher_api = NULL;
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001383 int ret = -EINVAL;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001384 char dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385
Milan Broz5ebaee62010-08-12 04:14:07 +01001386 /* Convert to crypto api definition? */
1387 if (strchr(cipher_in, '(')) {
1388 ti->error = "Bad cipher specification";
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389 return -EINVAL;
1390 }
1391
Milan Broz7dbcd132011-01-13 19:59:52 +00001392 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
1393 if (!cc->cipher_string)
1394 goto bad_mem;
1395
Milan Broz5ebaee62010-08-12 04:14:07 +01001396 /*
1397 * Legacy dm-crypt cipher specification
Milan Brozd1f96422011-01-13 19:59:54 +00001398 * cipher[:keycount]-mode-iv:ivopts
Milan Broz5ebaee62010-08-12 04:14:07 +01001399 */
1400 tmp = cipher_in;
Milan Brozd1f96422011-01-13 19:59:54 +00001401 keycount = strsep(&tmp, "-");
1402 cipher = strsep(&keycount, ":");
1403
1404 if (!keycount)
1405 cc->tfms_count = 1;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001406 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
Milan Brozd1f96422011-01-13 19:59:54 +00001407 !is_power_of_2(cc->tfms_count)) {
1408 ti->error = "Bad cipher key count specification";
1409 return -EINVAL;
1410 }
1411 cc->key_parts = cc->tfms_count;
Milan Broz5ebaee62010-08-12 04:14:07 +01001412
1413 cc->cipher = kstrdup(cipher, GFP_KERNEL);
1414 if (!cc->cipher)
1415 goto bad_mem;
1416
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 chainmode = strsep(&tmp, "-");
1418 ivopts = strsep(&tmp, "-");
1419 ivmode = strsep(&ivopts, ":");
1420
1421 if (tmp)
Milan Broz5ebaee62010-08-12 04:14:07 +01001422 DMWARN("Ignoring unexpected additional cipher options");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001423
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001424 cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)),
Milan Brozd1f96422011-01-13 19:59:54 +00001425 __alignof__(struct crypt_cpu));
Andi Kleenc0297722011-01-13 19:59:53 +00001426 if (!cc->cpu) {
1427 ti->error = "Cannot allocate per cpu state";
1428 goto bad_mem;
1429 }
1430
Milan Broz7dbcd132011-01-13 19:59:52 +00001431 /*
1432 * For compatibility with the original dm-crypt mapping format, if
1433 * only the cipher name is supplied, use cbc-plain.
1434 */
Milan Broz5ebaee62010-08-12 04:14:07 +01001435 if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001436 chainmode = "cbc";
1437 ivmode = "plain";
1438 }
1439
Herbert Xud1806f62006-08-22 20:29:17 +10001440 if (strcmp(chainmode, "ecb") && !ivmode) {
Milan Broz5ebaee62010-08-12 04:14:07 +01001441 ti->error = "IV mechanism required";
1442 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001443 }
1444
Milan Broz5ebaee62010-08-12 04:14:07 +01001445 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
1446 if (!cipher_api)
1447 goto bad_mem;
1448
1449 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
1450 "%s(%s)", chainmode, cipher);
1451 if (ret < 0) {
1452 kfree(cipher_api);
1453 goto bad_mem;
Herbert Xud1806f62006-08-22 20:29:17 +10001454 }
1455
Milan Broz5ebaee62010-08-12 04:14:07 +01001456 /* Allocate cipher */
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001457 ret = crypt_alloc_tfms(cc, cipher_api);
1458 if (ret < 0) {
1459 ti->error = "Error allocating crypto tfm";
1460 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462
Milan Broz5ebaee62010-08-12 04:14:07 +01001463 /* Initialize and set key */
1464 ret = crypt_set_key(cc, key);
Milan Broz28513fc2010-08-12 04:14:06 +01001465 if (ret < 0) {
Milan Broz0b430952009-12-10 23:51:55 +00001466 ti->error = "Error decoding and setting key";
Milan Broz28513fc2010-08-12 04:14:06 +01001467 goto bad;
Milan Broz0b430952009-12-10 23:51:55 +00001468 }
1469
Milan Broz5ebaee62010-08-12 04:14:07 +01001470 /* Initialize IV */
Andi Kleenc0297722011-01-13 19:59:53 +00001471 cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
Milan Broz5ebaee62010-08-12 04:14:07 +01001472 if (cc->iv_size)
1473 /* at least a 64 bit sector number should fit in our buffer */
1474 cc->iv_size = max(cc->iv_size,
1475 (unsigned int)(sizeof(u64) / sizeof(u8)));
1476 else if (ivmode) {
1477 DMWARN("Selected cipher does not support IVs");
1478 ivmode = NULL;
1479 }
1480
1481 /* Choose ivmode, see comments at iv code. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482 if (ivmode == NULL)
1483 cc->iv_gen_ops = NULL;
1484 else if (strcmp(ivmode, "plain") == 0)
1485 cc->iv_gen_ops = &crypt_iv_plain_ops;
Milan Broz61afef62009-12-10 23:52:25 +00001486 else if (strcmp(ivmode, "plain64") == 0)
1487 cc->iv_gen_ops = &crypt_iv_plain64_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001488 else if (strcmp(ivmode, "essiv") == 0)
1489 cc->iv_gen_ops = &crypt_iv_essiv_ops;
Rik Snel48527fa2006-09-03 08:56:39 +10001490 else if (strcmp(ivmode, "benbi") == 0)
1491 cc->iv_gen_ops = &crypt_iv_benbi_ops;
Ludwig Nussel46b47732007-05-09 02:32:55 -07001492 else if (strcmp(ivmode, "null") == 0)
1493 cc->iv_gen_ops = &crypt_iv_null_ops;
Milan Broz34745782011-01-13 19:59:55 +00001494 else if (strcmp(ivmode, "lmk") == 0) {
1495 cc->iv_gen_ops = &crypt_iv_lmk_ops;
1496 /* Version 2 and 3 is recognised according
1497 * to length of provided multi-key string.
1498 * If present (version 3), last key is used as IV seed.
1499 */
1500 if (cc->key_size % cc->key_parts)
1501 cc->key_parts++;
1502 } else {
Milan Broz5ebaee62010-08-12 04:14:07 +01001503 ret = -EINVAL;
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001504 ti->error = "Invalid IV mode";
Milan Broz28513fc2010-08-12 04:14:06 +01001505 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001506 }
1507
Milan Broz28513fc2010-08-12 04:14:06 +01001508 /* Allocate IV */
1509 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
1510 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
1511 if (ret < 0) {
1512 ti->error = "Error creating IV";
1513 goto bad;
1514 }
Milan Brozb95bf2d2009-12-10 23:51:56 +00001515 }
1516
Milan Broz28513fc2010-08-12 04:14:06 +01001517 /* Initialize IV (set keys for ESSIV etc) */
1518 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
1519 ret = cc->iv_gen_ops->init(cc);
1520 if (ret < 0) {
1521 ti->error = "Error initialising IV";
1522 goto bad;
1523 }
1524 }
1525
Milan Broz5ebaee62010-08-12 04:14:07 +01001526 ret = 0;
1527bad:
1528 kfree(cipher_api);
1529 return ret;
1530
1531bad_mem:
1532 ti->error = "Cannot allocate cipher strings";
1533 return -ENOMEM;
1534}
1535
1536/*
1537 * Construct an encryption mapping:
1538 * <cipher> <key> <iv_offset> <dev_path> <start>
1539 */
1540static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
1541{
1542 struct crypt_config *cc;
Milan Broz772ae5f2011-08-02 12:32:08 +01001543 unsigned int key_size, opt_params;
Milan Broz5ebaee62010-08-12 04:14:07 +01001544 unsigned long long tmpll;
1545 int ret;
Milan Broz772ae5f2011-08-02 12:32:08 +01001546 struct dm_arg_set as;
1547 const char *opt_string;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001548 char dummy;
Milan Broz5ebaee62010-08-12 04:14:07 +01001549
Milan Broz772ae5f2011-08-02 12:32:08 +01001550 static struct dm_arg _args[] = {
1551 {0, 1, "Invalid number of feature args"},
1552 };
1553
1554 if (argc < 5) {
Milan Broz5ebaee62010-08-12 04:14:07 +01001555 ti->error = "Not enough arguments";
1556 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557 }
1558
Milan Broz5ebaee62010-08-12 04:14:07 +01001559 key_size = strlen(argv[1]) >> 1;
1560
1561 cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);
1562 if (!cc) {
1563 ti->error = "Cannot allocate encryption context";
1564 return -ENOMEM;
1565 }
Milan Broz69a8cfc2011-01-13 19:59:49 +00001566 cc->key_size = key_size;
Milan Broz5ebaee62010-08-12 04:14:07 +01001567
1568 ti->private = cc;
1569 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
1570 if (ret < 0)
1571 goto bad;
1572
Milan Broz28513fc2010-08-12 04:14:06 +01001573 ret = -ENOMEM;
Matthew Dobson93d23412006-03-26 01:37:50 -08001574 cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001575 if (!cc->io_pool) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001576 ti->error = "Cannot allocate crypt io mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001577 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578 }
1579
Milan Brozddd42ed2008-02-08 02:11:07 +00001580 cc->dmreq_start = sizeof(struct ablkcipher_request);
Andi Kleenc0297722011-01-13 19:59:53 +00001581 cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
Milan Brozddd42ed2008-02-08 02:11:07 +00001582 cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
Andi Kleenc0297722011-01-13 19:59:53 +00001583 cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) &
Milan Broz3a7f6c92008-02-08 02:11:14 +00001584 ~(crypto_tfm_ctx_alignment() - 1);
Milan Brozddd42ed2008-02-08 02:11:07 +00001585
1586 cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
1587 sizeof(struct dm_crypt_request) + cc->iv_size);
1588 if (!cc->req_pool) {
1589 ti->error = "Cannot allocate crypt request mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001590 goto bad;
Milan Brozddd42ed2008-02-08 02:11:07 +00001591 }
Milan Brozddd42ed2008-02-08 02:11:07 +00001592
Matthew Dobsona19b27c2006-03-26 01:37:45 -08001593 cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001594 if (!cc->page_pool) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001595 ti->error = "Cannot allocate page mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001596 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 }
1598
Jens Axboebb799ca2008-12-10 15:35:05 +01001599 cc->bs = bioset_create(MIN_IOS, 0);
Milan Broz6a24c712006-10-03 01:15:40 -07001600 if (!cc->bs) {
1601 ti->error = "Cannot allocate crypt bioset";
Milan Broz28513fc2010-08-12 04:14:06 +01001602 goto bad;
Milan Broz6a24c712006-10-03 01:15:40 -07001603 }
1604
Milan Broz28513fc2010-08-12 04:14:06 +01001605 ret = -EINVAL;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001606 if (sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001607 ti->error = "Invalid iv_offset sector";
Milan Broz28513fc2010-08-12 04:14:06 +01001608 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001609 }
Andrew Morton4ee218c2006-03-27 01:17:48 -08001610 cc->iv_offset = tmpll;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001611
Milan Broz28513fc2010-08-12 04:14:06 +01001612 if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) {
1613 ti->error = "Device lookup failed";
1614 goto bad;
1615 }
1616
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001617 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001618 ti->error = "Invalid device sector";
Milan Broz28513fc2010-08-12 04:14:06 +01001619 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620 }
Andrew Morton4ee218c2006-03-27 01:17:48 -08001621 cc->start = tmpll;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001622
Milan Broz772ae5f2011-08-02 12:32:08 +01001623 argv += 5;
1624 argc -= 5;
1625
1626 /* Optional parameters */
1627 if (argc) {
1628 as.argc = argc;
1629 as.argv = argv;
1630
1631 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
1632 if (ret)
1633 goto bad;
1634
1635 opt_string = dm_shift_arg(&as);
1636
1637 if (opt_params == 1 && opt_string &&
1638 !strcasecmp(opt_string, "allow_discards"))
Alasdair G Kergon55a62ee2013-03-01 22:45:47 +00001639 ti->num_discard_bios = 1;
Milan Broz772ae5f2011-08-02 12:32:08 +01001640 else if (opt_params) {
1641 ret = -EINVAL;
1642 ti->error = "Invalid feature arguments";
1643 goto bad;
1644 }
1645 }
1646
Milan Broz28513fc2010-08-12 04:14:06 +01001647 ret = -ENOMEM;
Tejun Heo670368a2013-07-30 08:40:21 -04001648 cc->io_queue = alloc_workqueue("kcryptd_io", WQ_MEM_RECLAIM, 1);
Milan Brozcabf08e2007-10-19 22:38:58 +01001649 if (!cc->io_queue) {
1650 ti->error = "Couldn't create kcryptd io queue";
Milan Broz28513fc2010-08-12 04:14:06 +01001651 goto bad;
Milan Brozcabf08e2007-10-19 22:38:58 +01001652 }
1653
Andi Kleenc0297722011-01-13 19:59:53 +00001654 cc->crypt_queue = alloc_workqueue("kcryptd",
Tejun Heo670368a2013-07-30 08:40:21 -04001655 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
Milan Brozcabf08e2007-10-19 22:38:58 +01001656 if (!cc->crypt_queue) {
Milan Broz9934a8b2007-10-19 22:38:57 +01001657 ti->error = "Couldn't create kcryptd queue";
Milan Broz28513fc2010-08-12 04:14:06 +01001658 goto bad;
Milan Broz9934a8b2007-10-19 22:38:57 +01001659 }
1660
Alasdair G Kergon55a62ee2013-03-01 22:45:47 +00001661 ti->num_flush_bios = 1;
Alasdair G Kergon0ac55482012-07-27 15:08:08 +01001662 ti->discard_zeroes_data_unsupported = true;
Milan Broz983c7db2011-09-25 23:26:21 +01001663
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 return 0;
1665
Milan Broz28513fc2010-08-12 04:14:06 +01001666bad:
1667 crypt_dtr(ti);
1668 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669}
1670
Mikulas Patocka7de3ee52012-12-21 20:23:41 +00001671static int crypt_map(struct dm_target *ti, struct bio *bio)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672{
Alasdair G Kergon028867a2007-07-12 17:26:32 +01001673 struct dm_crypt_io *io;
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001674 struct crypt_config *cc = ti->private;
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001675
Milan Broz772ae5f2011-08-02 12:32:08 +01001676 /*
1677 * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
1678 * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight
1679 * - for REQ_DISCARD caller must use flush if IO ordering matters
1680 */
1681 if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001682 bio->bi_bdev = cc->dev->bdev;
Milan Broz772ae5f2011-08-02 12:32:08 +01001683 if (bio_sectors(bio))
1684 bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector);
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001685 return DM_MAPIO_REMAPPED;
1686 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001687
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001688 io = crypt_io_alloc(cc, bio, dm_target_offset(ti, bio->bi_sector));
Milan Brozcabf08e2007-10-19 22:38:58 +01001689
Milan Broz20c82532011-01-13 19:59:53 +00001690 if (bio_data_dir(io->base_bio) == READ) {
1691 if (kcryptd_io_read(io, GFP_NOWAIT))
1692 kcryptd_queue_io(io);
1693 } else
Milan Brozcabf08e2007-10-19 22:38:58 +01001694 kcryptd_queue_crypt(io);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001695
Kiyoshi Uedad2a7ad22006-12-08 02:41:06 -08001696 return DM_MAPIO_SUBMITTED;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001697}
1698
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001699static void crypt_status(struct dm_target *ti, status_type_t type,
1700 unsigned status_flags, char *result, unsigned maxlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001701{
Milan Broz5ebaee62010-08-12 04:14:07 +01001702 struct crypt_config *cc = ti->private;
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001703 unsigned i, sz = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001704
1705 switch (type) {
1706 case STATUSTYPE_INFO:
1707 result[0] = '\0';
1708 break;
1709
1710 case STATUSTYPE_TABLE:
Milan Broz7dbcd132011-01-13 19:59:52 +00001711 DMEMIT("%s ", cc->cipher_string);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001712
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001713 if (cc->key_size > 0)
1714 for (i = 0; i < cc->key_size; i++)
1715 DMEMIT("%02x", cc->key[i]);
1716 else
1717 DMEMIT("-");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718
Andrew Morton4ee218c2006-03-27 01:17:48 -08001719 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
1720 cc->dev->name, (unsigned long long)cc->start);
Milan Broz772ae5f2011-08-02 12:32:08 +01001721
Alasdair G Kergon55a62ee2013-03-01 22:45:47 +00001722 if (ti->num_discard_bios)
Milan Broz772ae5f2011-08-02 12:32:08 +01001723 DMEMIT(" 1 allow_discards");
1724
Linus Torvalds1da177e2005-04-16 15:20:36 -07001725 break;
1726 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001727}
1728
Milan Broze48d4bb2006-10-03 01:15:37 -07001729static void crypt_postsuspend(struct dm_target *ti)
1730{
1731 struct crypt_config *cc = ti->private;
1732
1733 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1734}
1735
1736static int crypt_preresume(struct dm_target *ti)
1737{
1738 struct crypt_config *cc = ti->private;
1739
1740 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
1741 DMERR("aborting resume - crypt key is not set.");
1742 return -EAGAIN;
1743 }
1744
1745 return 0;
1746}
1747
1748static void crypt_resume(struct dm_target *ti)
1749{
1750 struct crypt_config *cc = ti->private;
1751
1752 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1753}
1754
1755/* Message interface
1756 * key set <key>
1757 * key wipe
1758 */
1759static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
1760{
1761 struct crypt_config *cc = ti->private;
Milan Broz542da312009-12-10 23:51:57 +00001762 int ret = -EINVAL;
Milan Broze48d4bb2006-10-03 01:15:37 -07001763
1764 if (argc < 2)
1765 goto error;
1766
Mike Snitzer498f0102011-08-02 12:32:04 +01001767 if (!strcasecmp(argv[0], "key")) {
Milan Broze48d4bb2006-10-03 01:15:37 -07001768 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
1769 DMWARN("not suspended during key manipulation.");
1770 return -EINVAL;
1771 }
Mike Snitzer498f0102011-08-02 12:32:04 +01001772 if (argc == 3 && !strcasecmp(argv[1], "set")) {
Milan Broz542da312009-12-10 23:51:57 +00001773 ret = crypt_set_key(cc, argv[2]);
1774 if (ret)
1775 return ret;
1776 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
1777 ret = cc->iv_gen_ops->init(cc);
1778 return ret;
1779 }
Mike Snitzer498f0102011-08-02 12:32:04 +01001780 if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
Milan Broz542da312009-12-10 23:51:57 +00001781 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
1782 ret = cc->iv_gen_ops->wipe(cc);
1783 if (ret)
1784 return ret;
1785 }
Milan Broze48d4bb2006-10-03 01:15:37 -07001786 return crypt_wipe_key(cc);
Milan Broz542da312009-12-10 23:51:57 +00001787 }
Milan Broze48d4bb2006-10-03 01:15:37 -07001788 }
1789
1790error:
1791 DMWARN("unrecognised message received.");
1792 return -EINVAL;
1793}
1794
Milan Brozd41e26b2008-07-21 12:00:40 +01001795static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
1796 struct bio_vec *biovec, int max_size)
1797{
1798 struct crypt_config *cc = ti->private;
1799 struct request_queue *q = bdev_get_queue(cc->dev->bdev);
1800
1801 if (!q->merge_bvec_fn)
1802 return max_size;
1803
1804 bvm->bi_bdev = cc->dev->bdev;
Alasdair G Kergonb441a2622010-08-12 04:14:11 +01001805 bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector);
Milan Brozd41e26b2008-07-21 12:00:40 +01001806
1807 return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
1808}
1809
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001810static int crypt_iterate_devices(struct dm_target *ti,
1811 iterate_devices_callout_fn fn, void *data)
1812{
1813 struct crypt_config *cc = ti->private;
1814
Mike Snitzer5dea2712009-07-23 20:30:42 +01001815 return fn(ti, cc->dev, cc->start, ti->len, data);
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001816}
1817
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818static struct target_type crypt_target = {
1819 .name = "crypt",
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001820 .version = {1, 12, 1},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001821 .module = THIS_MODULE,
1822 .ctr = crypt_ctr,
1823 .dtr = crypt_dtr,
1824 .map = crypt_map,
1825 .status = crypt_status,
Milan Broze48d4bb2006-10-03 01:15:37 -07001826 .postsuspend = crypt_postsuspend,
1827 .preresume = crypt_preresume,
1828 .resume = crypt_resume,
1829 .message = crypt_message,
Milan Brozd41e26b2008-07-21 12:00:40 +01001830 .merge = crypt_merge,
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001831 .iterate_devices = crypt_iterate_devices,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001832};
1833
1834static int __init dm_crypt_init(void)
1835{
1836 int r;
1837
Alasdair G Kergon028867a2007-07-12 17:26:32 +01001838 _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001839 if (!_crypt_io_pool)
1840 return -ENOMEM;
1841
Linus Torvalds1da177e2005-04-16 15:20:36 -07001842 r = dm_register_target(&crypt_target);
1843 if (r < 0) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001844 DMERR("register failed %d", r);
Milan Broz9934a8b2007-10-19 22:38:57 +01001845 kmem_cache_destroy(_crypt_io_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001846 }
1847
Linus Torvalds1da177e2005-04-16 15:20:36 -07001848 return r;
1849}
1850
1851static void __exit dm_crypt_exit(void)
1852{
Mikulas Patocka10d3bd02009-01-06 03:04:58 +00001853 dm_unregister_target(&crypt_target);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001854 kmem_cache_destroy(_crypt_io_pool);
1855}
1856
1857module_init(dm_crypt_init);
1858module_exit(dm_crypt_exit);
1859
1860MODULE_AUTHOR("Christophe Saout <christophe@saout.de>");
1861MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
1862MODULE_LICENSE("GPL");