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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
Neil Brown644bd2f2007-10-16 13:48:46 +0200861 for (i = 0; i < clone->bi_vcnt; i++) {
Milan Broz8b004452006-10-03 01:15:37 -0700862 bv = bio_iovec_idx(clone, i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 BUG_ON(!bv->bv_page);
864 mempool_free(bv->bv_page, cc->page_pool);
865 bv->bv_page = NULL;
866 }
867}
868
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100869static struct dm_crypt_io *crypt_io_alloc(struct crypt_config *cc,
Milan Brozdc440d1e2008-10-10 13:37:03 +0100870 struct bio *bio, sector_t sector)
871{
Milan Brozdc440d1e2008-10-10 13:37:03 +0100872 struct dm_crypt_io *io;
873
874 io = mempool_alloc(cc->io_pool, GFP_NOIO);
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100875 io->cc = cc;
Milan Brozdc440d1e2008-10-10 13:37:03 +0100876 io->base_bio = bio;
877 io->sector = sector;
878 io->error = 0;
Milan Broz393b47e2008-10-21 17:45:02 +0100879 io->base_io = NULL;
Mikulas Patocka40b62292012-07-27 15:08:04 +0100880 atomic_set(&io->io_pending, 0);
Milan Brozdc440d1e2008-10-10 13:37:03 +0100881
882 return io;
883}
884
Milan Broz3e1a8bd2008-10-10 13:37:02 +0100885static void crypt_inc_pending(struct dm_crypt_io *io)
886{
Mikulas Patocka40b62292012-07-27 15:08:04 +0100887 atomic_inc(&io->io_pending);
Milan Broz3e1a8bd2008-10-10 13:37:02 +0100888}
889
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890/*
891 * One of the bios was finished. Check for completion of
892 * the whole request and correctly clean up the buffer.
Milan Broz393b47e2008-10-21 17:45:02 +0100893 * If base_io is set, wait for the last fragment to complete.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894 */
Milan Broz5742fd72008-02-08 02:10:43 +0000895static void crypt_dec_pending(struct dm_crypt_io *io)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700896{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100897 struct crypt_config *cc = io->cc;
Milan Brozb35f8ca2009-03-16 17:44:36 +0000898 struct bio *base_bio = io->base_bio;
899 struct dm_crypt_io *base_io = io->base_io;
900 int error = io->error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
Mikulas Patocka40b62292012-07-27 15:08:04 +0100902 if (!atomic_dec_and_test(&io->io_pending))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903 return;
904
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 mempool_free(io, cc->io_pool);
Milan Brozb35f8ca2009-03-16 17:44:36 +0000906
907 if (likely(!base_io))
908 bio_endio(base_bio, error);
909 else {
910 if (error && !base_io->error)
911 base_io->error = error;
912 crypt_dec_pending(base_io);
913 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914}
915
916/*
Milan Brozcabf08e2007-10-19 22:38:58 +0100917 * kcryptd/kcryptd_io:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 *
919 * Needed because it would be very unwise to do decryption in an
Milan Broz23541d22006-10-03 01:15:39 -0700920 * interrupt context.
Milan Brozcabf08e2007-10-19 22:38:58 +0100921 *
922 * kcryptd performs the actual encryption or decryption.
923 *
924 * kcryptd_io performs the IO submission.
925 *
926 * They must be separated as otherwise the final stages could be
927 * starved by new requests which can block in the first stages due
928 * to memory allocation.
Andi Kleenc0297722011-01-13 19:59:53 +0000929 *
930 * The work is done per CPU global for all dm-crypt instances.
931 * They should not depend on each other and do not block.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 */
NeilBrown6712ecf2007-09-27 12:47:43 +0200933static void crypt_endio(struct bio *clone, int error)
Milan Broz8b004452006-10-03 01:15:37 -0700934{
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100935 struct dm_crypt_io *io = clone->bi_private;
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100936 struct crypt_config *cc = io->cc;
Milan Brozee7a4912008-02-08 02:10:46 +0000937 unsigned rw = bio_data_dir(clone);
Milan Broz8b004452006-10-03 01:15:37 -0700938
Milan Brozadfe4772007-12-13 14:15:51 +0000939 if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error))
940 error = -EIO;
941
Milan Broz8b004452006-10-03 01:15:37 -0700942 /*
NeilBrown6712ecf2007-09-27 12:47:43 +0200943 * free the processed pages
Milan Broz8b004452006-10-03 01:15:37 -0700944 */
Milan Brozee7a4912008-02-08 02:10:46 +0000945 if (rw == WRITE)
Neil Brown644bd2f2007-10-16 13:48:46 +0200946 crypt_free_buffer_pages(cc, clone);
Milan Brozee7a4912008-02-08 02:10:46 +0000947
948 bio_put(clone);
949
950 if (rw == READ && !error) {
951 kcryptd_queue_crypt(io);
952 return;
NeilBrown6712ecf2007-09-27 12:47:43 +0200953 }
Milan Broz8b004452006-10-03 01:15:37 -0700954
Milan Brozadfe4772007-12-13 14:15:51 +0000955 if (unlikely(error))
Milan Broz5742fd72008-02-08 02:10:43 +0000956 io->error = error;
957
958 crypt_dec_pending(io);
Milan Broz8b004452006-10-03 01:15:37 -0700959}
960
Alasdair G Kergon028867a2007-07-12 17:26:32 +0100961static void clone_init(struct dm_crypt_io *io, struct bio *clone)
Milan Broz8b004452006-10-03 01:15:37 -0700962{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100963 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -0700964
965 clone->bi_private = io;
966 clone->bi_end_io = crypt_endio;
967 clone->bi_bdev = cc->dev->bdev;
968 clone->bi_rw = io->base_bio->bi_rw;
969}
970
Milan Broz20c82532011-01-13 19:59:53 +0000971static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
Milan Broz8b004452006-10-03 01:15:37 -0700972{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +0100973 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -0700974 struct bio *base_bio = io->base_bio;
975 struct bio *clone;
Milan Broz93e605c2006-10-03 01:15:38 -0700976
Milan Broz8b004452006-10-03 01:15:37 -0700977 /*
978 * The block layer might modify the bvec array, so always
979 * copy the required bvecs because we need the original
980 * one in order to decrypt the whole bio data *afterwards*.
981 */
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700982 clone = bio_clone_bioset(base_bio, gfp, cc->bs);
Jens Axboe7eaceac2011-03-10 08:52:07 +0100983 if (!clone)
Milan Broz20c82532011-01-13 19:59:53 +0000984 return 1;
Milan Broz8b004452006-10-03 01:15:37 -0700985
Milan Broz20c82532011-01-13 19:59:53 +0000986 crypt_inc_pending(io);
987
Milan Broz8b004452006-10-03 01:15:37 -0700988 clone_init(io, clone);
Milan Broz0c395b02008-02-08 02:10:54 +0000989 clone->bi_sector = cc->start + io->sector;
Milan Broz8b004452006-10-03 01:15:37 -0700990
Milan Broz93e605c2006-10-03 01:15:38 -0700991 generic_make_request(clone);
Milan Broz20c82532011-01-13 19:59:53 +0000992 return 0;
Milan Broz8b004452006-10-03 01:15:37 -0700993}
994
Milan Broz4e4eef62008-02-08 02:10:49 +0000995static void kcryptd_io_write(struct dm_crypt_io *io)
996{
Milan Broz95497a92008-02-08 02:11:12 +0000997 struct bio *clone = io->ctx.bio_out;
Milan Broz95497a92008-02-08 02:11:12 +0000998 generic_make_request(clone);
Milan Broz4e4eef62008-02-08 02:10:49 +0000999}
1000
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001001static void kcryptd_io(struct work_struct *work)
1002{
1003 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1004
Milan Broz20c82532011-01-13 19:59:53 +00001005 if (bio_data_dir(io->base_bio) == READ) {
1006 crypt_inc_pending(io);
1007 if (kcryptd_io_read(io, GFP_NOIO))
1008 io->error = -ENOMEM;
1009 crypt_dec_pending(io);
1010 } else
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001011 kcryptd_io_write(io);
1012}
1013
1014static void kcryptd_queue_io(struct dm_crypt_io *io)
1015{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001016 struct crypt_config *cc = io->cc;
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001017
1018 INIT_WORK(&io->work, kcryptd_io);
1019 queue_work(cc->io_queue, &io->work);
1020}
1021
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001022static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
Milan Broz4e4eef62008-02-08 02:10:49 +00001023{
Milan Brozdec1ced2008-02-08 02:10:57 +00001024 struct bio *clone = io->ctx.bio_out;
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001025 struct crypt_config *cc = io->cc;
Milan Brozdec1ced2008-02-08 02:10:57 +00001026
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001027 if (unlikely(io->error < 0)) {
Milan Brozdec1ced2008-02-08 02:10:57 +00001028 crypt_free_buffer_pages(cc, clone);
1029 bio_put(clone);
Milan Broz6c031f42008-10-10 13:37:06 +01001030 crypt_dec_pending(io);
Milan Brozdec1ced2008-02-08 02:10:57 +00001031 return;
1032 }
1033
1034 /* crypt_convert should have filled the clone bio */
1035 BUG_ON(io->ctx.idx_out < clone->bi_vcnt);
1036
1037 clone->bi_sector = cc->start + io->sector;
Milan Broz899c95d2008-02-08 02:11:02 +00001038
Milan Broz95497a92008-02-08 02:11:12 +00001039 if (async)
1040 kcryptd_queue_io(io);
Alasdair G Kergon1e37bb82008-10-10 13:37:05 +01001041 else
Milan Broz95497a92008-02-08 02:11:12 +00001042 generic_make_request(clone);
Milan Broz4e4eef62008-02-08 02:10:49 +00001043}
1044
Milan Brozfc5a5e92008-10-10 13:37:04 +01001045static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
Milan Broz8b004452006-10-03 01:15:37 -07001046{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001047 struct crypt_config *cc = io->cc;
Milan Broz8b004452006-10-03 01:15:37 -07001048 struct bio *clone;
Milan Broz393b47e2008-10-21 17:45:02 +01001049 struct dm_crypt_io *new_io;
Milan Brozc8081612008-10-10 13:37:08 +01001050 int crypt_finished;
Milan Broz933f01d2008-10-10 13:37:08 +01001051 unsigned out_of_pages = 0;
Milan Brozdec1ced2008-02-08 02:10:57 +00001052 unsigned remaining = io->base_bio->bi_size;
Milan Brozb635b002008-10-21 17:45:00 +01001053 sector_t sector = io->sector;
Milan Brozdec1ced2008-02-08 02:10:57 +00001054 int r;
Milan Broz8b004452006-10-03 01:15:37 -07001055
Milan Broz93e605c2006-10-03 01:15:38 -07001056 /*
Milan Brozfc5a5e92008-10-10 13:37:04 +01001057 * Prevent io from disappearing until this function completes.
1058 */
1059 crypt_inc_pending(io);
Milan Brozb635b002008-10-21 17:45:00 +01001060 crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector);
Milan Brozfc5a5e92008-10-10 13:37:04 +01001061
1062 /*
Milan Broz93e605c2006-10-03 01:15:38 -07001063 * The allocated buffers can be smaller than the whole bio,
1064 * so repeat the whole process until all the data can be handled.
1065 */
1066 while (remaining) {
Milan Broz933f01d2008-10-10 13:37:08 +01001067 clone = crypt_alloc_buffer(io, remaining, &out_of_pages);
Milan Broz23541d22006-10-03 01:15:39 -07001068 if (unlikely(!clone)) {
Milan Broz5742fd72008-02-08 02:10:43 +00001069 io->error = -ENOMEM;
Milan Brozfc5a5e92008-10-10 13:37:04 +01001070 break;
Milan Broz23541d22006-10-03 01:15:39 -07001071 }
Milan Broz93e605c2006-10-03 01:15:38 -07001072
Milan Broz53017032008-02-08 02:10:38 +00001073 io->ctx.bio_out = clone;
1074 io->ctx.idx_out = 0;
Milan Broz93e605c2006-10-03 01:15:38 -07001075
Milan Broz93e605c2006-10-03 01:15:38 -07001076 remaining -= clone->bi_size;
Milan Brozb635b002008-10-21 17:45:00 +01001077 sector += bio_sectors(clone);
Milan Brozdec1ced2008-02-08 02:10:57 +00001078
Milan Broz4e594092008-10-10 13:37:07 +01001079 crypt_inc_pending(io);
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001080
Milan Brozdec1ced2008-02-08 02:10:57 +00001081 r = crypt_convert(cc, &io->ctx);
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001082 if (r < 0)
1083 io->error = -EIO;
1084
Mikulas Patocka40b62292012-07-27 15:08:04 +01001085 crypt_finished = atomic_dec_and_test(&io->ctx.cc_pending);
Milan Brozdec1ced2008-02-08 02:10:57 +00001086
Milan Brozc8081612008-10-10 13:37:08 +01001087 /* Encryption was already finished, submit io now */
1088 if (crypt_finished) {
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001089 kcryptd_crypt_write_io_submit(io, 0);
Milan Brozc8081612008-10-10 13:37:08 +01001090
1091 /*
1092 * If there was an error, do not try next fragments.
1093 * For async, error is processed in async handler.
1094 */
Milan Broz6c031f42008-10-10 13:37:06 +01001095 if (unlikely(r < 0))
Milan Brozfc5a5e92008-10-10 13:37:04 +01001096 break;
Milan Brozb635b002008-10-21 17:45:00 +01001097
1098 io->sector = sector;
Milan Broz4e594092008-10-10 13:37:07 +01001099 }
Milan Broz93e605c2006-10-03 01:15:38 -07001100
Milan Broz933f01d2008-10-10 13:37:08 +01001101 /*
1102 * Out of memory -> run queues
1103 * But don't wait if split was due to the io size restriction
1104 */
1105 if (unlikely(out_of_pages))
Jens Axboe8aa7e842009-07-09 14:52:32 +02001106 congestion_wait(BLK_RW_ASYNC, HZ/100);
Milan Broz933f01d2008-10-10 13:37:08 +01001107
Milan Broz393b47e2008-10-21 17:45:02 +01001108 /*
1109 * With async crypto it is unsafe to share the crypto context
1110 * between fragments, so switch to a new dm_crypt_io structure.
1111 */
1112 if (unlikely(!crypt_finished && remaining)) {
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001113 new_io = crypt_io_alloc(io->cc, io->base_bio,
Milan Broz393b47e2008-10-21 17:45:02 +01001114 sector);
1115 crypt_inc_pending(new_io);
1116 crypt_convert_init(cc, &new_io->ctx, NULL,
1117 io->base_bio, sector);
1118 new_io->ctx.idx_in = io->ctx.idx_in;
1119 new_io->ctx.offset_in = io->ctx.offset_in;
1120
1121 /*
1122 * Fragments after the first use the base_io
1123 * pending count.
1124 */
1125 if (!io->base_io)
1126 new_io->base_io = io;
1127 else {
1128 new_io->base_io = io->base_io;
1129 crypt_inc_pending(io->base_io);
1130 crypt_dec_pending(io);
1131 }
1132
1133 io = new_io;
1134 }
Milan Broz8b004452006-10-03 01:15:37 -07001135 }
Milan Broz899c95d2008-02-08 02:11:02 +00001136
1137 crypt_dec_pending(io);
Milan Broz84131db2008-02-08 02:10:59 +00001138}
1139
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001140static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
Milan Broz5742fd72008-02-08 02:10:43 +00001141{
Milan Broz5742fd72008-02-08 02:10:43 +00001142 crypt_dec_pending(io);
1143}
1144
Milan Broz4e4eef62008-02-08 02:10:49 +00001145static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
Milan Broz8b004452006-10-03 01:15:37 -07001146{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001147 struct crypt_config *cc = io->cc;
Milan Broz5742fd72008-02-08 02:10:43 +00001148 int r = 0;
Milan Broz8b004452006-10-03 01:15:37 -07001149
Milan Broz3e1a8bd2008-10-10 13:37:02 +01001150 crypt_inc_pending(io);
Milan Broz3a7f6c92008-02-08 02:11:14 +00001151
Milan Broz53017032008-02-08 02:10:38 +00001152 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
Milan Broz0c395b02008-02-08 02:10:54 +00001153 io->sector);
Milan Broz8b004452006-10-03 01:15:37 -07001154
Milan Broz5742fd72008-02-08 02:10:43 +00001155 r = crypt_convert(cc, &io->ctx);
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001156 if (r < 0)
1157 io->error = -EIO;
Milan Broz5742fd72008-02-08 02:10:43 +00001158
Mikulas Patocka40b62292012-07-27 15:08:04 +01001159 if (atomic_dec_and_test(&io->ctx.cc_pending))
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001160 kcryptd_crypt_read_done(io);
Milan Broz3a7f6c92008-02-08 02:11:14 +00001161
1162 crypt_dec_pending(io);
Milan Broz8b004452006-10-03 01:15:37 -07001163}
1164
Milan Broz95497a92008-02-08 02:11:12 +00001165static void kcryptd_async_done(struct crypto_async_request *async_req,
1166 int error)
1167{
Huang Yingb2174ee2009-03-16 17:44:33 +00001168 struct dm_crypt_request *dmreq = async_req->data;
1169 struct convert_context *ctx = dmreq->ctx;
Milan Broz95497a92008-02-08 02:11:12 +00001170 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001171 struct crypt_config *cc = io->cc;
Milan Broz95497a92008-02-08 02:11:12 +00001172
1173 if (error == -EINPROGRESS) {
1174 complete(&ctx->restart);
1175 return;
1176 }
1177
Milan Broz2dc53272011-01-13 19:59:54 +00001178 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
1179 error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq);
1180
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001181 if (error < 0)
1182 io->error = -EIO;
1183
Huang Yingb2174ee2009-03-16 17:44:33 +00001184 mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
Milan Broz95497a92008-02-08 02:11:12 +00001185
Mikulas Patocka40b62292012-07-27 15:08:04 +01001186 if (!atomic_dec_and_test(&ctx->cc_pending))
Milan Broz95497a92008-02-08 02:11:12 +00001187 return;
1188
1189 if (bio_data_dir(io->base_bio) == READ)
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001190 kcryptd_crypt_read_done(io);
Milan Broz95497a92008-02-08 02:11:12 +00001191 else
Mikulas Patocka72c6e7a2012-03-28 18:41:22 +01001192 kcryptd_crypt_write_io_submit(io, 1);
Milan Broz95497a92008-02-08 02:11:12 +00001193}
1194
Milan Broz4e4eef62008-02-08 02:10:49 +00001195static void kcryptd_crypt(struct work_struct *work)
1196{
1197 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1198
1199 if (bio_data_dir(io->base_bio) == READ)
1200 kcryptd_crypt_read_convert(io);
1201 else
1202 kcryptd_crypt_write_convert(io);
Milan Broz8b004452006-10-03 01:15:37 -07001203}
1204
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001205static void kcryptd_queue_crypt(struct dm_crypt_io *io)
1206{
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001207 struct crypt_config *cc = io->cc;
Alasdair G Kergon395b1672008-02-08 02:10:52 +00001208
1209 INIT_WORK(&io->work, kcryptd_crypt);
1210 queue_work(cc->crypt_queue, &io->work);
1211}
1212
Linus Torvalds1da177e2005-04-16 15:20:36 -07001213/*
1214 * Decode key from its hex representation
1215 */
1216static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
1217{
1218 char buffer[3];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001219 unsigned int i;
1220
1221 buffer[2] = '\0';
1222
Milan Broz8b004452006-10-03 01:15:37 -07001223 for (i = 0; i < size; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224 buffer[0] = *hex++;
1225 buffer[1] = *hex++;
1226
majianpeng1a66a082012-07-27 15:07:59 +01001227 if (kstrtou8(buffer, 16, &key[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 return -EINVAL;
1229 }
1230
1231 if (*hex != '\0')
1232 return -EINVAL;
1233
1234 return 0;
1235}
1236
1237/*
1238 * Encode key into its hex representation
1239 */
1240static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
1241{
1242 unsigned int i;
1243
Milan Broz8b004452006-10-03 01:15:37 -07001244 for (i = 0; i < size; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245 sprintf(hex, "%02x", *key);
1246 hex += 2;
1247 key++;
1248 }
1249}
1250
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001251static void crypt_free_tfms(struct crypt_config *cc)
Milan Brozd1f96422011-01-13 19:59:54 +00001252{
Milan Brozd1f96422011-01-13 19:59:54 +00001253 unsigned i;
1254
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001255 if (!cc->tfms)
1256 return;
1257
Milan Brozd1f96422011-01-13 19:59:54 +00001258 for (i = 0; i < cc->tfms_count; i++)
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001259 if (cc->tfms[i] && !IS_ERR(cc->tfms[i])) {
1260 crypto_free_ablkcipher(cc->tfms[i]);
1261 cc->tfms[i] = NULL;
Milan Brozd1f96422011-01-13 19:59:54 +00001262 }
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001263
1264 kfree(cc->tfms);
1265 cc->tfms = NULL;
Milan Brozd1f96422011-01-13 19:59:54 +00001266}
1267
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001268static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
Milan Brozd1f96422011-01-13 19:59:54 +00001269{
Milan Brozd1f96422011-01-13 19:59:54 +00001270 unsigned i;
1271 int err;
1272
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001273 cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_ablkcipher *),
1274 GFP_KERNEL);
1275 if (!cc->tfms)
1276 return -ENOMEM;
1277
Milan Brozd1f96422011-01-13 19:59:54 +00001278 for (i = 0; i < cc->tfms_count; i++) {
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001279 cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
1280 if (IS_ERR(cc->tfms[i])) {
1281 err = PTR_ERR(cc->tfms[i]);
1282 crypt_free_tfms(cc);
Milan Brozd1f96422011-01-13 19:59:54 +00001283 return err;
1284 }
1285 }
1286
1287 return 0;
1288}
1289
Andi Kleenc0297722011-01-13 19:59:53 +00001290static int crypt_setkey_allcpus(struct crypt_config *cc)
1291{
Milan Brozd1f96422011-01-13 19:59:54 +00001292 unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count);
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001293 int err = 0, i, r;
Andi Kleenc0297722011-01-13 19:59:53 +00001294
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001295 for (i = 0; i < cc->tfms_count; i++) {
1296 r = crypto_ablkcipher_setkey(cc->tfms[i],
1297 cc->key + (i * subkey_size),
1298 subkey_size);
1299 if (r)
1300 err = r;
Andi Kleenc0297722011-01-13 19:59:53 +00001301 }
1302
1303 return err;
1304}
1305
Milan Broze48d4bb2006-10-03 01:15:37 -07001306static int crypt_set_key(struct crypt_config *cc, char *key)
1307{
Milan Brozde8be5a2011-03-24 13:54:27 +00001308 int r = -EINVAL;
1309 int key_string_len = strlen(key);
1310
Milan Broz69a8cfc2011-01-13 19:59:49 +00001311 /* The key size may not be changed. */
Milan Brozde8be5a2011-03-24 13:54:27 +00001312 if (cc->key_size != (key_string_len >> 1))
1313 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001314
Milan Broz69a8cfc2011-01-13 19:59:49 +00001315 /* Hyphen (which gives a key_size of zero) means there is no key. */
1316 if (!cc->key_size && strcmp(key, "-"))
Milan Brozde8be5a2011-03-24 13:54:27 +00001317 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001318
Milan Broz69a8cfc2011-01-13 19:59:49 +00001319 if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
Milan Brozde8be5a2011-03-24 13:54:27 +00001320 goto out;
Milan Broze48d4bb2006-10-03 01:15:37 -07001321
1322 set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1323
Milan Brozde8be5a2011-03-24 13:54:27 +00001324 r = crypt_setkey_allcpus(cc);
1325
1326out:
1327 /* Hex key string not needed after here, so wipe it. */
1328 memset(key, '0', key_string_len);
1329
1330 return r;
Milan Broze48d4bb2006-10-03 01:15:37 -07001331}
1332
1333static int crypt_wipe_key(struct crypt_config *cc)
1334{
1335 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
1336 memset(&cc->key, 0, cc->key_size * sizeof(u8));
Andi Kleenc0297722011-01-13 19:59:53 +00001337
1338 return crypt_setkey_allcpus(cc);
Milan Broze48d4bb2006-10-03 01:15:37 -07001339}
1340
Milan Broz28513fc2010-08-12 04:14:06 +01001341static void crypt_dtr(struct dm_target *ti)
1342{
1343 struct crypt_config *cc = ti->private;
Andi Kleenc0297722011-01-13 19:59:53 +00001344 struct crypt_cpu *cpu_cc;
1345 int cpu;
Milan Broz28513fc2010-08-12 04:14:06 +01001346
1347 ti->private = NULL;
1348
1349 if (!cc)
1350 return;
1351
1352 if (cc->io_queue)
1353 destroy_workqueue(cc->io_queue);
1354 if (cc->crypt_queue)
1355 destroy_workqueue(cc->crypt_queue);
1356
Andi Kleenc0297722011-01-13 19:59:53 +00001357 if (cc->cpu)
1358 for_each_possible_cpu(cpu) {
1359 cpu_cc = per_cpu_ptr(cc->cpu, cpu);
1360 if (cpu_cc->req)
1361 mempool_free(cpu_cc->req, cc->req_pool);
Andi Kleenc0297722011-01-13 19:59:53 +00001362 }
1363
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001364 crypt_free_tfms(cc);
1365
Milan Broz28513fc2010-08-12 04:14:06 +01001366 if (cc->bs)
1367 bioset_free(cc->bs);
1368
1369 if (cc->page_pool)
1370 mempool_destroy(cc->page_pool);
1371 if (cc->req_pool)
1372 mempool_destroy(cc->req_pool);
1373 if (cc->io_pool)
1374 mempool_destroy(cc->io_pool);
1375
1376 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
1377 cc->iv_gen_ops->dtr(cc);
1378
Milan Broz28513fc2010-08-12 04:14:06 +01001379 if (cc->dev)
1380 dm_put_device(ti, cc->dev);
1381
Andi Kleenc0297722011-01-13 19:59:53 +00001382 if (cc->cpu)
1383 free_percpu(cc->cpu);
1384
Milan Broz5ebaee62010-08-12 04:14:07 +01001385 kzfree(cc->cipher);
Milan Broz7dbcd132011-01-13 19:59:52 +00001386 kzfree(cc->cipher_string);
Milan Broz28513fc2010-08-12 04:14:06 +01001387
1388 /* Must zero key material before freeing */
1389 kzfree(cc);
1390}
1391
Milan Broz5ebaee62010-08-12 04:14:07 +01001392static int crypt_ctr_cipher(struct dm_target *ti,
1393 char *cipher_in, char *key)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394{
Milan Broz5ebaee62010-08-12 04:14:07 +01001395 struct crypt_config *cc = ti->private;
Milan Brozd1f96422011-01-13 19:59:54 +00001396 char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
Milan Broz5ebaee62010-08-12 04:14:07 +01001397 char *cipher_api = NULL;
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001398 int ret = -EINVAL;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001399 char dummy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001400
Milan Broz5ebaee62010-08-12 04:14:07 +01001401 /* Convert to crypto api definition? */
1402 if (strchr(cipher_in, '(')) {
1403 ti->error = "Bad cipher specification";
Linus Torvalds1da177e2005-04-16 15:20:36 -07001404 return -EINVAL;
1405 }
1406
Milan Broz7dbcd132011-01-13 19:59:52 +00001407 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
1408 if (!cc->cipher_string)
1409 goto bad_mem;
1410
Milan Broz5ebaee62010-08-12 04:14:07 +01001411 /*
1412 * Legacy dm-crypt cipher specification
Milan Brozd1f96422011-01-13 19:59:54 +00001413 * cipher[:keycount]-mode-iv:ivopts
Milan Broz5ebaee62010-08-12 04:14:07 +01001414 */
1415 tmp = cipher_in;
Milan Brozd1f96422011-01-13 19:59:54 +00001416 keycount = strsep(&tmp, "-");
1417 cipher = strsep(&keycount, ":");
1418
1419 if (!keycount)
1420 cc->tfms_count = 1;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001421 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
Milan Brozd1f96422011-01-13 19:59:54 +00001422 !is_power_of_2(cc->tfms_count)) {
1423 ti->error = "Bad cipher key count specification";
1424 return -EINVAL;
1425 }
1426 cc->key_parts = cc->tfms_count;
Milan Broz5ebaee62010-08-12 04:14:07 +01001427
1428 cc->cipher = kstrdup(cipher, GFP_KERNEL);
1429 if (!cc->cipher)
1430 goto bad_mem;
1431
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432 chainmode = strsep(&tmp, "-");
1433 ivopts = strsep(&tmp, "-");
1434 ivmode = strsep(&ivopts, ":");
1435
1436 if (tmp)
Milan Broz5ebaee62010-08-12 04:14:07 +01001437 DMWARN("Ignoring unexpected additional cipher options");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001439 cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)),
Milan Brozd1f96422011-01-13 19:59:54 +00001440 __alignof__(struct crypt_cpu));
Andi Kleenc0297722011-01-13 19:59:53 +00001441 if (!cc->cpu) {
1442 ti->error = "Cannot allocate per cpu state";
1443 goto bad_mem;
1444 }
1445
Milan Broz7dbcd132011-01-13 19:59:52 +00001446 /*
1447 * For compatibility with the original dm-crypt mapping format, if
1448 * only the cipher name is supplied, use cbc-plain.
1449 */
Milan Broz5ebaee62010-08-12 04:14:07 +01001450 if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001451 chainmode = "cbc";
1452 ivmode = "plain";
1453 }
1454
Herbert Xud1806f62006-08-22 20:29:17 +10001455 if (strcmp(chainmode, "ecb") && !ivmode) {
Milan Broz5ebaee62010-08-12 04:14:07 +01001456 ti->error = "IV mechanism required";
1457 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001458 }
1459
Milan Broz5ebaee62010-08-12 04:14:07 +01001460 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
1461 if (!cipher_api)
1462 goto bad_mem;
1463
1464 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
1465 "%s(%s)", chainmode, cipher);
1466 if (ret < 0) {
1467 kfree(cipher_api);
1468 goto bad_mem;
Herbert Xud1806f62006-08-22 20:29:17 +10001469 }
1470
Milan Broz5ebaee62010-08-12 04:14:07 +01001471 /* Allocate cipher */
Mikulas Patockafd2d2312012-07-27 15:08:05 +01001472 ret = crypt_alloc_tfms(cc, cipher_api);
1473 if (ret < 0) {
1474 ti->error = "Error allocating crypto tfm";
1475 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001477
Milan Broz5ebaee62010-08-12 04:14:07 +01001478 /* Initialize and set key */
1479 ret = crypt_set_key(cc, key);
Milan Broz28513fc2010-08-12 04:14:06 +01001480 if (ret < 0) {
Milan Broz0b430952009-12-10 23:51:55 +00001481 ti->error = "Error decoding and setting key";
Milan Broz28513fc2010-08-12 04:14:06 +01001482 goto bad;
Milan Broz0b430952009-12-10 23:51:55 +00001483 }
1484
Milan Broz5ebaee62010-08-12 04:14:07 +01001485 /* Initialize IV */
Andi Kleenc0297722011-01-13 19:59:53 +00001486 cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
Milan Broz5ebaee62010-08-12 04:14:07 +01001487 if (cc->iv_size)
1488 /* at least a 64 bit sector number should fit in our buffer */
1489 cc->iv_size = max(cc->iv_size,
1490 (unsigned int)(sizeof(u64) / sizeof(u8)));
1491 else if (ivmode) {
1492 DMWARN("Selected cipher does not support IVs");
1493 ivmode = NULL;
1494 }
1495
1496 /* Choose ivmode, see comments at iv code. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001497 if (ivmode == NULL)
1498 cc->iv_gen_ops = NULL;
1499 else if (strcmp(ivmode, "plain") == 0)
1500 cc->iv_gen_ops = &crypt_iv_plain_ops;
Milan Broz61afef62009-12-10 23:52:25 +00001501 else if (strcmp(ivmode, "plain64") == 0)
1502 cc->iv_gen_ops = &crypt_iv_plain64_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001503 else if (strcmp(ivmode, "essiv") == 0)
1504 cc->iv_gen_ops = &crypt_iv_essiv_ops;
Rik Snel48527fa2006-09-03 08:56:39 +10001505 else if (strcmp(ivmode, "benbi") == 0)
1506 cc->iv_gen_ops = &crypt_iv_benbi_ops;
Ludwig Nussel46b47732007-05-09 02:32:55 -07001507 else if (strcmp(ivmode, "null") == 0)
1508 cc->iv_gen_ops = &crypt_iv_null_ops;
Milan Broz34745782011-01-13 19:59:55 +00001509 else if (strcmp(ivmode, "lmk") == 0) {
1510 cc->iv_gen_ops = &crypt_iv_lmk_ops;
1511 /* Version 2 and 3 is recognised according
1512 * to length of provided multi-key string.
1513 * If present (version 3), last key is used as IV seed.
1514 */
1515 if (cc->key_size % cc->key_parts)
1516 cc->key_parts++;
1517 } else {
Milan Broz5ebaee62010-08-12 04:14:07 +01001518 ret = -EINVAL;
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001519 ti->error = "Invalid IV mode";
Milan Broz28513fc2010-08-12 04:14:06 +01001520 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521 }
1522
Milan Broz28513fc2010-08-12 04:14:06 +01001523 /* Allocate IV */
1524 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
1525 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
1526 if (ret < 0) {
1527 ti->error = "Error creating IV";
1528 goto bad;
1529 }
Milan Brozb95bf2d2009-12-10 23:51:56 +00001530 }
1531
Milan Broz28513fc2010-08-12 04:14:06 +01001532 /* Initialize IV (set keys for ESSIV etc) */
1533 if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
1534 ret = cc->iv_gen_ops->init(cc);
1535 if (ret < 0) {
1536 ti->error = "Error initialising IV";
1537 goto bad;
1538 }
1539 }
1540
Milan Broz5ebaee62010-08-12 04:14:07 +01001541 ret = 0;
1542bad:
1543 kfree(cipher_api);
1544 return ret;
1545
1546bad_mem:
1547 ti->error = "Cannot allocate cipher strings";
1548 return -ENOMEM;
1549}
1550
1551/*
1552 * Construct an encryption mapping:
1553 * <cipher> <key> <iv_offset> <dev_path> <start>
1554 */
1555static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
1556{
1557 struct crypt_config *cc;
Milan Broz772ae5f2011-08-02 12:32:08 +01001558 unsigned int key_size, opt_params;
Milan Broz5ebaee62010-08-12 04:14:07 +01001559 unsigned long long tmpll;
1560 int ret;
Milan Broz772ae5f2011-08-02 12:32:08 +01001561 struct dm_arg_set as;
1562 const char *opt_string;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001563 char dummy;
Milan Broz5ebaee62010-08-12 04:14:07 +01001564
Milan Broz772ae5f2011-08-02 12:32:08 +01001565 static struct dm_arg _args[] = {
1566 {0, 1, "Invalid number of feature args"},
1567 };
1568
1569 if (argc < 5) {
Milan Broz5ebaee62010-08-12 04:14:07 +01001570 ti->error = "Not enough arguments";
1571 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001572 }
1573
Milan Broz5ebaee62010-08-12 04:14:07 +01001574 key_size = strlen(argv[1]) >> 1;
1575
1576 cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL);
1577 if (!cc) {
1578 ti->error = "Cannot allocate encryption context";
1579 return -ENOMEM;
1580 }
Milan Broz69a8cfc2011-01-13 19:59:49 +00001581 cc->key_size = key_size;
Milan Broz5ebaee62010-08-12 04:14:07 +01001582
1583 ti->private = cc;
1584 ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
1585 if (ret < 0)
1586 goto bad;
1587
Milan Broz28513fc2010-08-12 04:14:06 +01001588 ret = -ENOMEM;
Matthew Dobson93d23412006-03-26 01:37:50 -08001589 cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001590 if (!cc->io_pool) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001591 ti->error = "Cannot allocate crypt io mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001592 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 }
1594
Milan Brozddd42ed2008-02-08 02:11:07 +00001595 cc->dmreq_start = sizeof(struct ablkcipher_request);
Andi Kleenc0297722011-01-13 19:59:53 +00001596 cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
Milan Brozddd42ed2008-02-08 02:11:07 +00001597 cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
Andi Kleenc0297722011-01-13 19:59:53 +00001598 cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) &
Milan Broz3a7f6c92008-02-08 02:11:14 +00001599 ~(crypto_tfm_ctx_alignment() - 1);
Milan Brozddd42ed2008-02-08 02:11:07 +00001600
1601 cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
1602 sizeof(struct dm_crypt_request) + cc->iv_size);
1603 if (!cc->req_pool) {
1604 ti->error = "Cannot allocate crypt request mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001605 goto bad;
Milan Brozddd42ed2008-02-08 02:11:07 +00001606 }
Milan Brozddd42ed2008-02-08 02:11:07 +00001607
Matthew Dobsona19b27c2006-03-26 01:37:45 -08001608 cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001609 if (!cc->page_pool) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001610 ti->error = "Cannot allocate page mempool";
Milan Broz28513fc2010-08-12 04:14:06 +01001611 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001612 }
1613
Jens Axboebb799ca2008-12-10 15:35:05 +01001614 cc->bs = bioset_create(MIN_IOS, 0);
Milan Broz6a24c712006-10-03 01:15:40 -07001615 if (!cc->bs) {
1616 ti->error = "Cannot allocate crypt bioset";
Milan Broz28513fc2010-08-12 04:14:06 +01001617 goto bad;
Milan Broz6a24c712006-10-03 01:15:40 -07001618 }
1619
Milan Broz28513fc2010-08-12 04:14:06 +01001620 ret = -EINVAL;
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001621 if (sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001622 ti->error = "Invalid iv_offset sector";
Milan Broz28513fc2010-08-12 04:14:06 +01001623 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001624 }
Andrew Morton4ee218c2006-03-27 01:17:48 -08001625 cc->iv_offset = tmpll;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001626
Milan Broz28513fc2010-08-12 04:14:06 +01001627 if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) {
1628 ti->error = "Device lookup failed";
1629 goto bad;
1630 }
1631
Mikulas Patocka31998ef2012-03-28 18:41:26 +01001632 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001633 ti->error = "Invalid device sector";
Milan Broz28513fc2010-08-12 04:14:06 +01001634 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001635 }
Andrew Morton4ee218c2006-03-27 01:17:48 -08001636 cc->start = tmpll;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637
Milan Broz772ae5f2011-08-02 12:32:08 +01001638 argv += 5;
1639 argc -= 5;
1640
1641 /* Optional parameters */
1642 if (argc) {
1643 as.argc = argc;
1644 as.argv = argv;
1645
1646 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
1647 if (ret)
1648 goto bad;
1649
1650 opt_string = dm_shift_arg(&as);
1651
1652 if (opt_params == 1 && opt_string &&
1653 !strcasecmp(opt_string, "allow_discards"))
1654 ti->num_discard_requests = 1;
1655 else if (opt_params) {
1656 ret = -EINVAL;
1657 ti->error = "Invalid feature arguments";
1658 goto bad;
1659 }
1660 }
1661
Milan Broz28513fc2010-08-12 04:14:06 +01001662 ret = -ENOMEM;
Andi Kleenc0297722011-01-13 19:59:53 +00001663 cc->io_queue = alloc_workqueue("kcryptd_io",
1664 WQ_NON_REENTRANT|
1665 WQ_MEM_RECLAIM,
1666 1);
Milan Brozcabf08e2007-10-19 22:38:58 +01001667 if (!cc->io_queue) {
1668 ti->error = "Couldn't create kcryptd io queue";
Milan Broz28513fc2010-08-12 04:14:06 +01001669 goto bad;
Milan Brozcabf08e2007-10-19 22:38:58 +01001670 }
1671
Andi Kleenc0297722011-01-13 19:59:53 +00001672 cc->crypt_queue = alloc_workqueue("kcryptd",
1673 WQ_NON_REENTRANT|
1674 WQ_CPU_INTENSIVE|
1675 WQ_MEM_RECLAIM,
1676 1);
Milan Brozcabf08e2007-10-19 22:38:58 +01001677 if (!cc->crypt_queue) {
Milan Broz9934a8b2007-10-19 22:38:57 +01001678 ti->error = "Couldn't create kcryptd queue";
Milan Broz28513fc2010-08-12 04:14:06 +01001679 goto bad;
Milan Broz9934a8b2007-10-19 22:38:57 +01001680 }
1681
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001682 ti->num_flush_requests = 1;
Alasdair G Kergon0ac55482012-07-27 15:08:08 +01001683 ti->discard_zeroes_data_unsupported = true;
Milan Broz983c7db2011-09-25 23:26:21 +01001684
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 return 0;
1686
Milan Broz28513fc2010-08-12 04:14:06 +01001687bad:
1688 crypt_dtr(ti);
1689 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690}
1691
Linus Torvalds1da177e2005-04-16 15:20:36 -07001692static int crypt_map(struct dm_target *ti, struct bio *bio,
1693 union map_info *map_context)
1694{
Alasdair G Kergon028867a2007-07-12 17:26:32 +01001695 struct dm_crypt_io *io;
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001696 struct crypt_config *cc = ti->private;
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001697
Milan Broz772ae5f2011-08-02 12:32:08 +01001698 /*
1699 * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
1700 * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight
1701 * - for REQ_DISCARD caller must use flush if IO ordering matters
1702 */
1703 if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001704 bio->bi_bdev = cc->dev->bdev;
Milan Broz772ae5f2011-08-02 12:32:08 +01001705 if (bio_sectors(bio))
1706 bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector);
Mikulas Patocka647c7db2009-06-22 10:12:23 +01001707 return DM_MAPIO_REMAPPED;
1708 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001709
Alasdair G Kergon49a8a922012-07-27 15:08:05 +01001710 io = crypt_io_alloc(cc, bio, dm_target_offset(ti, bio->bi_sector));
Milan Brozcabf08e2007-10-19 22:38:58 +01001711
Milan Broz20c82532011-01-13 19:59:53 +00001712 if (bio_data_dir(io->base_bio) == READ) {
1713 if (kcryptd_io_read(io, GFP_NOWAIT))
1714 kcryptd_queue_io(io);
1715 } else
Milan Brozcabf08e2007-10-19 22:38:58 +01001716 kcryptd_queue_crypt(io);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001717
Kiyoshi Uedad2a7ad22006-12-08 02:41:06 -08001718 return DM_MAPIO_SUBMITTED;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001719}
1720
1721static int crypt_status(struct dm_target *ti, status_type_t type,
Alasdair G Kergon1f4e0ff2012-07-27 15:08:16 +01001722 unsigned status_flags, char *result, unsigned maxlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001723{
Milan Broz5ebaee62010-08-12 04:14:07 +01001724 struct crypt_config *cc = ti->private;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001725 unsigned int sz = 0;
1726
1727 switch (type) {
1728 case STATUSTYPE_INFO:
1729 result[0] = '\0';
1730 break;
1731
1732 case STATUSTYPE_TABLE:
Milan Broz7dbcd132011-01-13 19:59:52 +00001733 DMEMIT("%s ", cc->cipher_string);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001734
1735 if (cc->key_size > 0) {
1736 if ((maxlen - sz) < ((cc->key_size << 1) + 1))
1737 return -ENOMEM;
1738
1739 crypt_encode_key(result + sz, cc->key, cc->key_size);
1740 sz += cc->key_size << 1;
1741 } else {
1742 if (sz >= maxlen)
1743 return -ENOMEM;
1744 result[sz++] = '-';
1745 }
1746
Andrew Morton4ee218c2006-03-27 01:17:48 -08001747 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
1748 cc->dev->name, (unsigned long long)cc->start);
Milan Broz772ae5f2011-08-02 12:32:08 +01001749
1750 if (ti->num_discard_requests)
1751 DMEMIT(" 1 allow_discards");
1752
Linus Torvalds1da177e2005-04-16 15:20:36 -07001753 break;
1754 }
1755 return 0;
1756}
1757
Milan Broze48d4bb2006-10-03 01:15:37 -07001758static void crypt_postsuspend(struct dm_target *ti)
1759{
1760 struct crypt_config *cc = ti->private;
1761
1762 set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1763}
1764
1765static int crypt_preresume(struct dm_target *ti)
1766{
1767 struct crypt_config *cc = ti->private;
1768
1769 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
1770 DMERR("aborting resume - crypt key is not set.");
1771 return -EAGAIN;
1772 }
1773
1774 return 0;
1775}
1776
1777static void crypt_resume(struct dm_target *ti)
1778{
1779 struct crypt_config *cc = ti->private;
1780
1781 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
1782}
1783
1784/* Message interface
1785 * key set <key>
1786 * key wipe
1787 */
1788static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
1789{
1790 struct crypt_config *cc = ti->private;
Milan Broz542da312009-12-10 23:51:57 +00001791 int ret = -EINVAL;
Milan Broze48d4bb2006-10-03 01:15:37 -07001792
1793 if (argc < 2)
1794 goto error;
1795
Mike Snitzer498f0102011-08-02 12:32:04 +01001796 if (!strcasecmp(argv[0], "key")) {
Milan Broze48d4bb2006-10-03 01:15:37 -07001797 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
1798 DMWARN("not suspended during key manipulation.");
1799 return -EINVAL;
1800 }
Mike Snitzer498f0102011-08-02 12:32:04 +01001801 if (argc == 3 && !strcasecmp(argv[1], "set")) {
Milan Broz542da312009-12-10 23:51:57 +00001802 ret = crypt_set_key(cc, argv[2]);
1803 if (ret)
1804 return ret;
1805 if (cc->iv_gen_ops && cc->iv_gen_ops->init)
1806 ret = cc->iv_gen_ops->init(cc);
1807 return ret;
1808 }
Mike Snitzer498f0102011-08-02 12:32:04 +01001809 if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
Milan Broz542da312009-12-10 23:51:57 +00001810 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
1811 ret = cc->iv_gen_ops->wipe(cc);
1812 if (ret)
1813 return ret;
1814 }
Milan Broze48d4bb2006-10-03 01:15:37 -07001815 return crypt_wipe_key(cc);
Milan Broz542da312009-12-10 23:51:57 +00001816 }
Milan Broze48d4bb2006-10-03 01:15:37 -07001817 }
1818
1819error:
1820 DMWARN("unrecognised message received.");
1821 return -EINVAL;
1822}
1823
Milan Brozd41e26b2008-07-21 12:00:40 +01001824static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
1825 struct bio_vec *biovec, int max_size)
1826{
1827 struct crypt_config *cc = ti->private;
1828 struct request_queue *q = bdev_get_queue(cc->dev->bdev);
1829
1830 if (!q->merge_bvec_fn)
1831 return max_size;
1832
1833 bvm->bi_bdev = cc->dev->bdev;
Alasdair G Kergonb441a2622010-08-12 04:14:11 +01001834 bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector);
Milan Brozd41e26b2008-07-21 12:00:40 +01001835
1836 return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
1837}
1838
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001839static int crypt_iterate_devices(struct dm_target *ti,
1840 iterate_devices_callout_fn fn, void *data)
1841{
1842 struct crypt_config *cc = ti->private;
1843
Mike Snitzer5dea2712009-07-23 20:30:42 +01001844 return fn(ti, cc->dev, cc->start, ti->len, data);
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001845}
1846
Linus Torvalds1da177e2005-04-16 15:20:36 -07001847static struct target_type crypt_target = {
1848 .name = "crypt",
Milan Broz772ae5f2011-08-02 12:32:08 +01001849 .version = {1, 11, 0},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001850 .module = THIS_MODULE,
1851 .ctr = crypt_ctr,
1852 .dtr = crypt_dtr,
1853 .map = crypt_map,
1854 .status = crypt_status,
Milan Broze48d4bb2006-10-03 01:15:37 -07001855 .postsuspend = crypt_postsuspend,
1856 .preresume = crypt_preresume,
1857 .resume = crypt_resume,
1858 .message = crypt_message,
Milan Brozd41e26b2008-07-21 12:00:40 +01001859 .merge = crypt_merge,
Mike Snitzeraf4874e2009-06-22 10:12:33 +01001860 .iterate_devices = crypt_iterate_devices,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001861};
1862
1863static int __init dm_crypt_init(void)
1864{
1865 int r;
1866
Alasdair G Kergon028867a2007-07-12 17:26:32 +01001867 _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001868 if (!_crypt_io_pool)
1869 return -ENOMEM;
1870
Linus Torvalds1da177e2005-04-16 15:20:36 -07001871 r = dm_register_target(&crypt_target);
1872 if (r < 0) {
Alasdair G Kergon72d94862006-06-26 00:27:35 -07001873 DMERR("register failed %d", r);
Milan Broz9934a8b2007-10-19 22:38:57 +01001874 kmem_cache_destroy(_crypt_io_pool);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001875 }
1876
Linus Torvalds1da177e2005-04-16 15:20:36 -07001877 return r;
1878}
1879
1880static void __exit dm_crypt_exit(void)
1881{
Mikulas Patocka10d3bd02009-01-06 03:04:58 +00001882 dm_unregister_target(&crypt_target);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001883 kmem_cache_destroy(_crypt_io_pool);
1884}
1885
1886module_init(dm_crypt_init);
1887module_exit(dm_crypt_exit);
1888
1889MODULE_AUTHOR("Christophe Saout <christophe@saout.de>");
1890MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
1891MODULE_LICENSE("GPL");