Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> |
| 3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 4 | * Copyright (C) 2006 Red Hat, Inc. All rights reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | * |
| 6 | * This file is released under the GPL. |
| 7 | */ |
| 8 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 9 | #include <linux/err.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/module.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/bio.h> |
| 14 | #include <linux/blkdev.h> |
| 15 | #include <linux/mempool.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/crypto.h> |
| 18 | #include <linux/workqueue.h> |
Andrew Morton | 3fcfab1 | 2006-10-19 23:28:16 -0700 | [diff] [blame] | 19 | #include <linux/backing-dev.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <asm/atomic.h> |
David Hardeman | 378f058 | 2005-09-17 17:55:31 +1000 | [diff] [blame] | 21 | #include <linux/scatterlist.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <asm/page.h> |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 23 | #include <asm/unaligned.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | |
| 25 | #include "dm.h" |
| 26 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 27 | #define DM_MSG_PREFIX "crypt" |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 28 | #define MESG_STR(x) x, sizeof(x) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | |
| 30 | /* |
| 31 | * per bio private data |
| 32 | */ |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 33 | struct dm_crypt_io { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | struct dm_target *target; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 35 | struct bio *base_bio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | struct work_struct work; |
| 37 | atomic_t pending; |
| 38 | int error; |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 39 | int post_process; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | }; |
| 41 | |
| 42 | /* |
| 43 | * context holding the current state of a multi-part conversion |
| 44 | */ |
| 45 | struct convert_context { |
| 46 | struct bio *bio_in; |
| 47 | struct bio *bio_out; |
| 48 | unsigned int offset_in; |
| 49 | unsigned int offset_out; |
| 50 | unsigned int idx_in; |
| 51 | unsigned int idx_out; |
| 52 | sector_t sector; |
| 53 | int write; |
| 54 | }; |
| 55 | |
| 56 | struct crypt_config; |
| 57 | |
| 58 | struct crypt_iv_operations { |
| 59 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, |
| 60 | const char *opts); |
| 61 | void (*dtr)(struct crypt_config *cc); |
| 62 | const char *(*status)(struct crypt_config *cc); |
| 63 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); |
| 64 | }; |
| 65 | |
| 66 | /* |
| 67 | * Crypt: maps a linear range of a block device |
| 68 | * and encrypts / decrypts at the same time. |
| 69 | */ |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 70 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | struct crypt_config { |
| 72 | struct dm_dev *dev; |
| 73 | sector_t start; |
| 74 | |
| 75 | /* |
| 76 | * pool for per bio private data and |
| 77 | * for encryption buffer pages |
| 78 | */ |
| 79 | mempool_t *io_pool; |
| 80 | mempool_t *page_pool; |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 81 | struct bio_set *bs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | |
| 83 | /* |
| 84 | * crypto related data |
| 85 | */ |
| 86 | struct crypt_iv_operations *iv_gen_ops; |
| 87 | char *iv_mode; |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 88 | union { |
| 89 | struct crypto_cipher *essiv_tfm; |
| 90 | int benbi_shift; |
| 91 | } iv_gen_private; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | sector_t iv_offset; |
| 93 | unsigned int iv_size; |
| 94 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 95 | char cipher[CRYPTO_MAX_ALG_NAME]; |
| 96 | char chainmode[CRYPTO_MAX_ALG_NAME]; |
| 97 | struct crypto_blkcipher *tfm; |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 98 | unsigned long flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | unsigned int key_size; |
| 100 | u8 key[0]; |
| 101 | }; |
| 102 | |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 103 | #define MIN_IOS 16 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | #define MIN_POOL_PAGES 32 |
| 105 | #define MIN_BIO_PAGES 8 |
| 106 | |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 107 | static struct kmem_cache *_crypt_io_pool; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 109 | static void clone_init(struct dm_crypt_io *, struct bio *); |
Olaf Kirch | 027581f | 2007-05-09 02:32:52 -0700 | [diff] [blame] | 110 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | * Different IV generation algorithms: |
| 113 | * |
Rik Snel | 3c164bd | 2006-09-02 18:17:33 +1000 | [diff] [blame] | 114 | * plain: the initial vector is the 32-bit little-endian version of the sector |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | * number, padded with zeros if neccessary. |
| 116 | * |
Rik Snel | 3c164bd | 2006-09-02 18:17:33 +1000 | [diff] [blame] | 117 | * essiv: "encrypted sector|salt initial vector", the sector number is |
| 118 | * encrypted with the bulk cipher using a salt as key. The salt |
| 119 | * should be derived from the bulk cipher's key via hashing. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | * |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 121 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
| 122 | * (needed for LRW-32-AES and possible other narrow block modes) |
| 123 | * |
Ludwig Nussel | 46b4773 | 2007-05-09 02:32:55 -0700 | [diff] [blame] | 124 | * null: the initial vector is always zero. Provides compatibility with |
| 125 | * obsolete loop_fish2 devices. Do not use for new devices. |
| 126 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | * plumb: unimplemented, see: |
| 128 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 |
| 129 | */ |
| 130 | |
| 131 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
| 132 | { |
| 133 | memset(iv, 0, cc->iv_size); |
| 134 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); |
| 135 | |
| 136 | return 0; |
| 137 | } |
| 138 | |
| 139 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, |
| 140 | const char *opts) |
| 141 | { |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 142 | struct crypto_cipher *essiv_tfm; |
Herbert Xu | 3505868 | 2006-08-24 19:10:20 +1000 | [diff] [blame] | 143 | struct crypto_hash *hash_tfm; |
| 144 | struct hash_desc desc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | struct scatterlist sg; |
| 146 | unsigned int saltsize; |
| 147 | u8 *salt; |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 148 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | |
| 150 | if (opts == NULL) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 151 | ti->error = "Digest algorithm missing for ESSIV mode"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | return -EINVAL; |
| 153 | } |
| 154 | |
| 155 | /* Hash the cipher key with the given hash algorithm */ |
Herbert Xu | 3505868 | 2006-08-24 19:10:20 +1000 | [diff] [blame] | 156 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
| 157 | if (IS_ERR(hash_tfm)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 158 | ti->error = "Error initializing ESSIV hash"; |
Herbert Xu | 3505868 | 2006-08-24 19:10:20 +1000 | [diff] [blame] | 159 | return PTR_ERR(hash_tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | } |
| 161 | |
Herbert Xu | 3505868 | 2006-08-24 19:10:20 +1000 | [diff] [blame] | 162 | saltsize = crypto_hash_digestsize(hash_tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | salt = kmalloc(saltsize, GFP_KERNEL); |
| 164 | if (salt == NULL) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 165 | ti->error = "Error kmallocing salt storage in ESSIV"; |
Herbert Xu | 3505868 | 2006-08-24 19:10:20 +1000 | [diff] [blame] | 166 | crypto_free_hash(hash_tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | return -ENOMEM; |
| 168 | } |
| 169 | |
David Hardeman | 378f058 | 2005-09-17 17:55:31 +1000 | [diff] [blame] | 170 | sg_set_buf(&sg, cc->key, cc->key_size); |
Herbert Xu | 3505868 | 2006-08-24 19:10:20 +1000 | [diff] [blame] | 171 | desc.tfm = hash_tfm; |
| 172 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; |
| 173 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); |
| 174 | crypto_free_hash(hash_tfm); |
| 175 | |
| 176 | if (err) { |
| 177 | ti->error = "Error calculating hash in ESSIV"; |
| 178 | return err; |
| 179 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | |
| 181 | /* Setup the essiv_tfm with the given salt */ |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 182 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
| 183 | if (IS_ERR(essiv_tfm)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 184 | ti->error = "Error allocating crypto tfm for ESSIV"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | kfree(salt); |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 186 | return PTR_ERR(essiv_tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | } |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 188 | if (crypto_cipher_blocksize(essiv_tfm) != |
| 189 | crypto_blkcipher_ivsize(cc->tfm)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 190 | ti->error = "Block size of ESSIV cipher does " |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | "not match IV size of block cipher"; |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 192 | crypto_free_cipher(essiv_tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | kfree(salt); |
| 194 | return -EINVAL; |
| 195 | } |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 196 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
| 197 | if (err) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 198 | ti->error = "Failed to set key for ESSIV cipher"; |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 199 | crypto_free_cipher(essiv_tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 200 | kfree(salt); |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 201 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | } |
| 203 | kfree(salt); |
| 204 | |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 205 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | return 0; |
| 207 | } |
| 208 | |
| 209 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) |
| 210 | { |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 211 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
| 212 | cc->iv_gen_private.essiv_tfm = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | } |
| 214 | |
| 215 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
| 216 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | memset(iv, 0, cc->iv_size); |
| 218 | *(u64 *)iv = cpu_to_le64(sector); |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 219 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | return 0; |
| 221 | } |
| 222 | |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 223 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
| 224 | const char *opts) |
| 225 | { |
| 226 | unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); |
David Howells | f0d1b0b | 2006-12-08 02:37:49 -0800 | [diff] [blame] | 227 | int log = ilog2(bs); |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 228 | |
| 229 | /* we need to calculate how far we must shift the sector count |
| 230 | * to get the cipher block count, we use this shift in _gen */ |
| 231 | |
| 232 | if (1 << log != bs) { |
| 233 | ti->error = "cypher blocksize is not a power of 2"; |
| 234 | return -EINVAL; |
| 235 | } |
| 236 | |
| 237 | if (log > 9) { |
| 238 | ti->error = "cypher blocksize is > 512"; |
| 239 | return -EINVAL; |
| 240 | } |
| 241 | |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 242 | cc->iv_gen_private.benbi_shift = 9 - log; |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 243 | |
| 244 | return 0; |
| 245 | } |
| 246 | |
| 247 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) |
| 248 | { |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 249 | } |
| 250 | |
| 251 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
| 252 | { |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 253 | __be64 val; |
| 254 | |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 255 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
Herbert Xu | 79066ad | 2006-12-05 13:41:52 -0800 | [diff] [blame] | 256 | |
| 257 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); |
| 258 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 259 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | return 0; |
| 261 | } |
| 262 | |
Ludwig Nussel | 46b4773 | 2007-05-09 02:32:55 -0700 | [diff] [blame] | 263 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
| 264 | { |
| 265 | memset(iv, 0, cc->iv_size); |
| 266 | |
| 267 | return 0; |
| 268 | } |
| 269 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
| 271 | .generator = crypt_iv_plain_gen |
| 272 | }; |
| 273 | |
| 274 | static struct crypt_iv_operations crypt_iv_essiv_ops = { |
| 275 | .ctr = crypt_iv_essiv_ctr, |
| 276 | .dtr = crypt_iv_essiv_dtr, |
| 277 | .generator = crypt_iv_essiv_gen |
| 278 | }; |
| 279 | |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 280 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
| 281 | .ctr = crypt_iv_benbi_ctr, |
| 282 | .dtr = crypt_iv_benbi_dtr, |
| 283 | .generator = crypt_iv_benbi_gen |
| 284 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | |
Ludwig Nussel | 46b4773 | 2007-05-09 02:32:55 -0700 | [diff] [blame] | 286 | static struct crypt_iv_operations crypt_iv_null_ops = { |
| 287 | .generator = crypt_iv_null_gen |
| 288 | }; |
| 289 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 290 | static int |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, |
| 292 | struct scatterlist *in, unsigned int length, |
| 293 | int write, sector_t sector) |
| 294 | { |
Herbert Xu | 4578932 | 2006-09-03 08:58:41 +1000 | [diff] [blame] | 295 | u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 296 | struct blkcipher_desc desc = { |
| 297 | .tfm = cc->tfm, |
| 298 | .info = iv, |
| 299 | .flags = CRYPTO_TFM_REQ_MAY_SLEEP, |
| 300 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | int r; |
| 302 | |
| 303 | if (cc->iv_gen_ops) { |
| 304 | r = cc->iv_gen_ops->generator(cc, iv, sector); |
| 305 | if (r < 0) |
| 306 | return r; |
| 307 | |
| 308 | if (write) |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 309 | r = crypto_blkcipher_encrypt_iv(&desc, out, in, length); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | else |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 311 | r = crypto_blkcipher_decrypt_iv(&desc, out, in, length); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | } else { |
| 313 | if (write) |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 314 | r = crypto_blkcipher_encrypt(&desc, out, in, length); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | else |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 316 | r = crypto_blkcipher_decrypt(&desc, out, in, length); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | } |
| 318 | |
| 319 | return r; |
| 320 | } |
| 321 | |
| 322 | static void |
| 323 | crypt_convert_init(struct crypt_config *cc, struct convert_context *ctx, |
| 324 | struct bio *bio_out, struct bio *bio_in, |
| 325 | sector_t sector, int write) |
| 326 | { |
| 327 | ctx->bio_in = bio_in; |
| 328 | ctx->bio_out = bio_out; |
| 329 | ctx->offset_in = 0; |
| 330 | ctx->offset_out = 0; |
| 331 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; |
| 332 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; |
| 333 | ctx->sector = sector + cc->iv_offset; |
| 334 | ctx->write = write; |
| 335 | } |
| 336 | |
| 337 | /* |
| 338 | * Encrypt / decrypt data from one bio to another one (can be the same one) |
| 339 | */ |
| 340 | static int crypt_convert(struct crypt_config *cc, |
| 341 | struct convert_context *ctx) |
| 342 | { |
| 343 | int r = 0; |
| 344 | |
| 345 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && |
| 346 | ctx->idx_out < ctx->bio_out->bi_vcnt) { |
| 347 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); |
| 348 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); |
| 349 | struct scatterlist sg_in = { |
| 350 | .page = bv_in->bv_page, |
| 351 | .offset = bv_in->bv_offset + ctx->offset_in, |
| 352 | .length = 1 << SECTOR_SHIFT |
| 353 | }; |
| 354 | struct scatterlist sg_out = { |
| 355 | .page = bv_out->bv_page, |
| 356 | .offset = bv_out->bv_offset + ctx->offset_out, |
| 357 | .length = 1 << SECTOR_SHIFT |
| 358 | }; |
| 359 | |
| 360 | ctx->offset_in += sg_in.length; |
| 361 | if (ctx->offset_in >= bv_in->bv_len) { |
| 362 | ctx->offset_in = 0; |
| 363 | ctx->idx_in++; |
| 364 | } |
| 365 | |
| 366 | ctx->offset_out += sg_out.length; |
| 367 | if (ctx->offset_out >= bv_out->bv_len) { |
| 368 | ctx->offset_out = 0; |
| 369 | ctx->idx_out++; |
| 370 | } |
| 371 | |
| 372 | r = crypt_convert_scatterlist(cc, &sg_out, &sg_in, sg_in.length, |
| 373 | ctx->write, ctx->sector); |
| 374 | if (r < 0) |
| 375 | break; |
| 376 | |
| 377 | ctx->sector++; |
| 378 | } |
| 379 | |
| 380 | return r; |
| 381 | } |
| 382 | |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 383 | static void dm_crypt_bio_destructor(struct bio *bio) |
| 384 | { |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 385 | struct dm_crypt_io *io = bio->bi_private; |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 386 | struct crypt_config *cc = io->target->private; |
| 387 | |
| 388 | bio_free(bio, cc->bs); |
| 389 | } |
| 390 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | /* |
| 392 | * Generate a new unfragmented bio with the given size |
| 393 | * This should never violate the device limitations |
| 394 | * May return a smaller bio when running out of pages |
| 395 | */ |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 396 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 397 | { |
Olaf Kirch | 027581f | 2007-05-09 02:32:52 -0700 | [diff] [blame] | 398 | struct crypt_config *cc = io->target->private; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 399 | struct bio *clone; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
Al Viro | b4e3ca1 | 2005-10-21 03:22:34 -0400 | [diff] [blame] | 401 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | unsigned int i; |
| 403 | |
Olaf Kirch | 2f9941b | 2007-05-09 02:32:53 -0700 | [diff] [blame] | 404 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 405 | if (!clone) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | |
Olaf Kirch | 027581f | 2007-05-09 02:32:52 -0700 | [diff] [blame] | 408 | clone_init(io, clone); |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 409 | |
Olaf Kirch | f97380b | 2007-05-09 02:32:54 -0700 | [diff] [blame] | 410 | for (i = 0; i < nr_iovecs; i++) { |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 411 | struct bio_vec *bv = bio_iovec_idx(clone, i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 412 | |
| 413 | bv->bv_page = mempool_alloc(cc->page_pool, gfp_mask); |
| 414 | if (!bv->bv_page) |
| 415 | break; |
| 416 | |
| 417 | /* |
| 418 | * if additional pages cannot be allocated without waiting, |
| 419 | * return a partially allocated bio, the caller will then try |
| 420 | * to allocate additional bios while submitting this partial bio |
| 421 | */ |
Olaf Kirch | f97380b | 2007-05-09 02:32:54 -0700 | [diff] [blame] | 422 | if (i == (MIN_BIO_PAGES - 1)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
| 424 | |
| 425 | bv->bv_offset = 0; |
| 426 | if (size > PAGE_SIZE) |
| 427 | bv->bv_len = PAGE_SIZE; |
| 428 | else |
| 429 | bv->bv_len = size; |
| 430 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 431 | clone->bi_size += bv->bv_len; |
| 432 | clone->bi_vcnt++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | size -= bv->bv_len; |
| 434 | } |
| 435 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 436 | if (!clone->bi_size) { |
| 437 | bio_put(clone); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | return NULL; |
| 439 | } |
| 440 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 441 | return clone; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | } |
| 443 | |
| 444 | static void crypt_free_buffer_pages(struct crypt_config *cc, |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 445 | struct bio *clone, unsigned int bytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | { |
| 447 | unsigned int i, start, end; |
| 448 | struct bio_vec *bv; |
| 449 | |
| 450 | /* |
| 451 | * This is ugly, but Jens Axboe thinks that using bi_idx in the |
| 452 | * endio function is too dangerous at the moment, so I calculate the |
| 453 | * correct position using bi_vcnt and bi_size. |
| 454 | * The bv_offset and bv_len fields might already be modified but we |
| 455 | * know that we always allocated whole pages. |
| 456 | * A fix to the bi_idx issue in the kernel is in the works, so |
| 457 | * we will hopefully be able to revert to the cleaner solution soon. |
| 458 | */ |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 459 | i = clone->bi_vcnt - 1; |
| 460 | bv = bio_iovec_idx(clone, i); |
| 461 | end = (i << PAGE_SHIFT) + (bv->bv_offset + bv->bv_len) - clone->bi_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | start = end - bytes; |
| 463 | |
| 464 | start >>= PAGE_SHIFT; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 465 | if (!clone->bi_size) |
| 466 | end = clone->bi_vcnt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | else |
| 468 | end >>= PAGE_SHIFT; |
| 469 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 470 | for (i = start; i < end; i++) { |
| 471 | bv = bio_iovec_idx(clone, i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 472 | BUG_ON(!bv->bv_page); |
| 473 | mempool_free(bv->bv_page, cc->page_pool); |
| 474 | bv->bv_page = NULL; |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | /* |
| 479 | * One of the bios was finished. Check for completion of |
| 480 | * the whole request and correctly clean up the buffer. |
| 481 | */ |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 482 | static void dec_pending(struct dm_crypt_io *io, int error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | { |
| 484 | struct crypt_config *cc = (struct crypt_config *) io->target->private; |
| 485 | |
| 486 | if (error < 0) |
| 487 | io->error = error; |
| 488 | |
| 489 | if (!atomic_dec_and_test(&io->pending)) |
| 490 | return; |
| 491 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 492 | bio_endio(io->base_bio, io->base_bio->bi_size, io->error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 493 | |
| 494 | mempool_free(io, cc->io_pool); |
| 495 | } |
| 496 | |
| 497 | /* |
| 498 | * kcryptd: |
| 499 | * |
| 500 | * Needed because it would be very unwise to do decryption in an |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 501 | * interrupt context. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 502 | */ |
| 503 | static struct workqueue_struct *_kcryptd_workqueue; |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 504 | static void kcryptd_do_work(struct work_struct *work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 505 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 506 | static void kcryptd_queue_io(struct dm_crypt_io *io) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 507 | { |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 508 | INIT_WORK(&io->work, kcryptd_do_work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | queue_work(_kcryptd_workqueue, &io->work); |
| 510 | } |
| 511 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 512 | static int crypt_endio(struct bio *clone, unsigned int done, int error) |
| 513 | { |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 514 | struct dm_crypt_io *io = clone->bi_private; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 515 | struct crypt_config *cc = io->target->private; |
| 516 | unsigned read_io = bio_data_dir(clone) == READ; |
| 517 | |
| 518 | /* |
| 519 | * free the processed pages, even if |
| 520 | * it's only a partially completed write |
| 521 | */ |
| 522 | if (!read_io) |
| 523 | crypt_free_buffer_pages(cc, clone, done); |
| 524 | |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 525 | /* keep going - not finished yet */ |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 526 | if (unlikely(clone->bi_size)) |
| 527 | return 1; |
| 528 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 529 | if (!read_io) |
| 530 | goto out; |
| 531 | |
| 532 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE))) { |
| 533 | error = -EIO; |
| 534 | goto out; |
| 535 | } |
| 536 | |
| 537 | bio_put(clone); |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 538 | io->post_process = 1; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 539 | kcryptd_queue_io(io); |
| 540 | return 0; |
| 541 | |
| 542 | out: |
| 543 | bio_put(clone); |
| 544 | dec_pending(io, error); |
| 545 | return error; |
| 546 | } |
| 547 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 548 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 549 | { |
| 550 | struct crypt_config *cc = io->target->private; |
| 551 | |
| 552 | clone->bi_private = io; |
| 553 | clone->bi_end_io = crypt_endio; |
| 554 | clone->bi_bdev = cc->dev->bdev; |
| 555 | clone->bi_rw = io->base_bio->bi_rw; |
Olaf Kirch | 027581f | 2007-05-09 02:32:52 -0700 | [diff] [blame] | 556 | clone->bi_destructor = dm_crypt_bio_destructor; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 557 | } |
| 558 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 559 | static void process_read(struct dm_crypt_io *io) |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 560 | { |
| 561 | struct crypt_config *cc = io->target->private; |
| 562 | struct bio *base_bio = io->base_bio; |
| 563 | struct bio *clone; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 564 | sector_t sector = base_bio->bi_sector - io->target->begin; |
| 565 | |
| 566 | atomic_inc(&io->pending); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 567 | |
| 568 | /* |
| 569 | * The block layer might modify the bvec array, so always |
| 570 | * copy the required bvecs because we need the original |
| 571 | * one in order to decrypt the whole bio data *afterwards*. |
| 572 | */ |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 573 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 574 | if (unlikely(!clone)) { |
| 575 | dec_pending(io, -ENOMEM); |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 576 | return; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 577 | } |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 578 | |
| 579 | clone_init(io, clone); |
| 580 | clone->bi_idx = 0; |
| 581 | clone->bi_vcnt = bio_segments(base_bio); |
| 582 | clone->bi_size = base_bio->bi_size; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 583 | clone->bi_sector = cc->start + sector; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 584 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
| 585 | sizeof(struct bio_vec) * clone->bi_vcnt); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 586 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 587 | generic_make_request(clone); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 588 | } |
| 589 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 590 | static void process_write(struct dm_crypt_io *io) |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 591 | { |
| 592 | struct crypt_config *cc = io->target->private; |
| 593 | struct bio *base_bio = io->base_bio; |
| 594 | struct bio *clone; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 595 | struct convert_context ctx; |
| 596 | unsigned remaining = base_bio->bi_size; |
| 597 | sector_t sector = base_bio->bi_sector - io->target->begin; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 598 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 599 | atomic_inc(&io->pending); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 600 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 601 | crypt_convert_init(cc, &ctx, NULL, base_bio, sector, 1); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 602 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 603 | /* |
| 604 | * The allocated buffers can be smaller than the whole bio, |
| 605 | * so repeat the whole process until all the data can be handled. |
| 606 | */ |
| 607 | while (remaining) { |
Olaf Kirch | f97380b | 2007-05-09 02:32:54 -0700 | [diff] [blame] | 608 | clone = crypt_alloc_buffer(io, remaining); |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 609 | if (unlikely(!clone)) { |
| 610 | dec_pending(io, -ENOMEM); |
| 611 | return; |
| 612 | } |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 613 | |
| 614 | ctx.bio_out = clone; |
Olaf Kirch | f97380b | 2007-05-09 02:32:54 -0700 | [diff] [blame] | 615 | ctx.idx_out = 0; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 616 | |
| 617 | if (unlikely(crypt_convert(cc, &ctx) < 0)) { |
| 618 | crypt_free_buffer_pages(cc, clone, clone->bi_size); |
| 619 | bio_put(clone); |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 620 | dec_pending(io, -EIO); |
| 621 | return; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 622 | } |
| 623 | |
Olaf Kirch | f97380b | 2007-05-09 02:32:54 -0700 | [diff] [blame] | 624 | /* crypt_convert should have filled the clone bio */ |
| 625 | BUG_ON(ctx.idx_out < clone->bi_vcnt); |
| 626 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 627 | clone->bi_sector = cc->start + sector; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 628 | remaining -= clone->bi_size; |
| 629 | sector += bio_sectors(clone); |
| 630 | |
Olaf Kirch | 2f9941b | 2007-05-09 02:32:53 -0700 | [diff] [blame] | 631 | /* Grab another reference to the io struct |
| 632 | * before we kick off the request */ |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 633 | if (remaining) |
| 634 | atomic_inc(&io->pending); |
| 635 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 636 | generic_make_request(clone); |
| 637 | |
Olaf Kirch | 98221eb | 2007-05-09 02:32:52 -0700 | [diff] [blame] | 638 | /* Do not reference clone after this - it |
| 639 | * may be gone already. */ |
| 640 | |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 641 | /* out of memory -> run queues */ |
| 642 | if (remaining) |
Olaf Kirch | 98221eb | 2007-05-09 02:32:52 -0700 | [diff] [blame] | 643 | congestion_wait(WRITE, HZ/100); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 644 | } |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 645 | } |
| 646 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 647 | static void process_read_endio(struct dm_crypt_io *io) |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 648 | { |
| 649 | struct crypt_config *cc = io->target->private; |
| 650 | struct convert_context ctx; |
| 651 | |
| 652 | crypt_convert_init(cc, &ctx, io->base_bio, io->base_bio, |
| 653 | io->base_bio->bi_sector - io->target->begin, 0); |
| 654 | |
| 655 | dec_pending(io, crypt_convert(cc, &ctx)); |
| 656 | } |
| 657 | |
David Howells | c402895 | 2006-11-22 14:57:56 +0000 | [diff] [blame] | 658 | static void kcryptd_do_work(struct work_struct *work) |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 659 | { |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 660 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 661 | |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 662 | if (io->post_process) |
| 663 | process_read_endio(io); |
| 664 | else if (bio_data_dir(io->base_bio) == READ) |
| 665 | process_read(io); |
| 666 | else |
| 667 | process_write(io); |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 668 | } |
| 669 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 670 | /* |
| 671 | * Decode key from its hex representation |
| 672 | */ |
| 673 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) |
| 674 | { |
| 675 | char buffer[3]; |
| 676 | char *endp; |
| 677 | unsigned int i; |
| 678 | |
| 679 | buffer[2] = '\0'; |
| 680 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 681 | for (i = 0; i < size; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 682 | buffer[0] = *hex++; |
| 683 | buffer[1] = *hex++; |
| 684 | |
| 685 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); |
| 686 | |
| 687 | if (endp != &buffer[2]) |
| 688 | return -EINVAL; |
| 689 | } |
| 690 | |
| 691 | if (*hex != '\0') |
| 692 | return -EINVAL; |
| 693 | |
| 694 | return 0; |
| 695 | } |
| 696 | |
| 697 | /* |
| 698 | * Encode key into its hex representation |
| 699 | */ |
| 700 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) |
| 701 | { |
| 702 | unsigned int i; |
| 703 | |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 704 | for (i = 0; i < size; i++) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | sprintf(hex, "%02x", *key); |
| 706 | hex += 2; |
| 707 | key++; |
| 708 | } |
| 709 | } |
| 710 | |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 711 | static int crypt_set_key(struct crypt_config *cc, char *key) |
| 712 | { |
| 713 | unsigned key_size = strlen(key) >> 1; |
| 714 | |
| 715 | if (cc->key_size && cc->key_size != key_size) |
| 716 | return -EINVAL; |
| 717 | |
| 718 | cc->key_size = key_size; /* initial settings */ |
| 719 | |
| 720 | if ((!key_size && strcmp(key, "-")) || |
| 721 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
| 722 | return -EINVAL; |
| 723 | |
| 724 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); |
| 725 | |
| 726 | return 0; |
| 727 | } |
| 728 | |
| 729 | static int crypt_wipe_key(struct crypt_config *cc) |
| 730 | { |
| 731 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); |
| 732 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); |
| 733 | return 0; |
| 734 | } |
| 735 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 736 | /* |
| 737 | * Construct an encryption mapping: |
| 738 | * <cipher> <key> <iv_offset> <dev_path> <start> |
| 739 | */ |
| 740 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) |
| 741 | { |
| 742 | struct crypt_config *cc; |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 743 | struct crypto_blkcipher *tfm; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | char *tmp; |
| 745 | char *cipher; |
| 746 | char *chainmode; |
| 747 | char *ivmode; |
| 748 | char *ivopts; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 749 | unsigned int key_size; |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 750 | unsigned long long tmpll; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 751 | |
| 752 | if (argc != 5) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 753 | ti->error = "Not enough arguments"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | return -EINVAL; |
| 755 | } |
| 756 | |
| 757 | tmp = argv[0]; |
| 758 | cipher = strsep(&tmp, "-"); |
| 759 | chainmode = strsep(&tmp, "-"); |
| 760 | ivopts = strsep(&tmp, "-"); |
| 761 | ivmode = strsep(&ivopts, ":"); |
| 762 | |
| 763 | if (tmp) |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 764 | DMWARN("Unexpected additional cipher options"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | |
| 766 | key_size = strlen(argv[1]) >> 1; |
| 767 | |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 768 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | if (cc == NULL) { |
| 770 | ti->error = |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 771 | "Cannot allocate transparent encryption context"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | return -ENOMEM; |
| 773 | } |
| 774 | |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 775 | if (crypt_set_key(cc, argv[1])) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 776 | ti->error = "Error decoding key"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | goto bad1; |
| 778 | } |
| 779 | |
| 780 | /* Compatiblity mode for old dm-crypt cipher strings */ |
| 781 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { |
| 782 | chainmode = "cbc"; |
| 783 | ivmode = "plain"; |
| 784 | } |
| 785 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 786 | if (strcmp(chainmode, "ecb") && !ivmode) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 787 | ti->error = "This chaining mode requires an IV mechanism"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 788 | goto bad1; |
| 789 | } |
| 790 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 791 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", chainmode, |
| 792 | cipher) >= CRYPTO_MAX_ALG_NAME) { |
| 793 | ti->error = "Chain mode + cipher name is too long"; |
| 794 | goto bad1; |
| 795 | } |
| 796 | |
| 797 | tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
| 798 | if (IS_ERR(tfm)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 799 | ti->error = "Error allocating crypto tfm"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | goto bad1; |
| 801 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 803 | strcpy(cc->cipher, cipher); |
| 804 | strcpy(cc->chainmode, chainmode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | cc->tfm = tfm; |
| 806 | |
| 807 | /* |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 808 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 809 | * See comments at iv code |
| 810 | */ |
| 811 | |
| 812 | if (ivmode == NULL) |
| 813 | cc->iv_gen_ops = NULL; |
| 814 | else if (strcmp(ivmode, "plain") == 0) |
| 815 | cc->iv_gen_ops = &crypt_iv_plain_ops; |
| 816 | else if (strcmp(ivmode, "essiv") == 0) |
| 817 | cc->iv_gen_ops = &crypt_iv_essiv_ops; |
Rik Snel | 48527fa | 2006-09-03 08:56:39 +1000 | [diff] [blame] | 818 | else if (strcmp(ivmode, "benbi") == 0) |
| 819 | cc->iv_gen_ops = &crypt_iv_benbi_ops; |
Ludwig Nussel | 46b4773 | 2007-05-09 02:32:55 -0700 | [diff] [blame] | 820 | else if (strcmp(ivmode, "null") == 0) |
| 821 | cc->iv_gen_ops = &crypt_iv_null_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | else { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 823 | ti->error = "Invalid IV mode"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 824 | goto bad2; |
| 825 | } |
| 826 | |
| 827 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && |
| 828 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) |
| 829 | goto bad2; |
| 830 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 831 | cc->iv_size = crypto_blkcipher_ivsize(tfm); |
| 832 | if (cc->iv_size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | /* at least a 64 bit sector number should fit in our buffer */ |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 834 | cc->iv_size = max(cc->iv_size, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
| 836 | else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | if (cc->iv_gen_ops) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 838 | DMWARN("Selected cipher does not support IVs"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | if (cc->iv_gen_ops->dtr) |
| 840 | cc->iv_gen_ops->dtr(cc); |
| 841 | cc->iv_gen_ops = NULL; |
| 842 | } |
| 843 | } |
| 844 | |
Matthew Dobson | 93d2341 | 2006-03-26 01:37:50 -0800 | [diff] [blame] | 845 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 846 | if (!cc->io_pool) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 847 | ti->error = "Cannot allocate crypt io mempool"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 848 | goto bad3; |
| 849 | } |
| 850 | |
Matthew Dobson | a19b27c | 2006-03-26 01:37:45 -0800 | [diff] [blame] | 851 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | if (!cc->page_pool) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 853 | ti->error = "Cannot allocate page mempool"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 854 | goto bad4; |
| 855 | } |
| 856 | |
Jens Axboe | 5972511 | 2007-04-02 10:06:42 +0200 | [diff] [blame] | 857 | cc->bs = bioset_create(MIN_IOS, MIN_IOS); |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 858 | if (!cc->bs) { |
| 859 | ti->error = "Cannot allocate crypt bioset"; |
| 860 | goto bad_bs; |
| 861 | } |
| 862 | |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 863 | if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 864 | ti->error = "Error setting key"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 865 | goto bad5; |
| 866 | } |
| 867 | |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 868 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 869 | ti->error = "Invalid iv_offset sector"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 870 | goto bad5; |
| 871 | } |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 872 | cc->iv_offset = tmpll; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 874 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 875 | ti->error = "Invalid device sector"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 876 | goto bad5; |
| 877 | } |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 878 | cc->start = tmpll; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 879 | |
| 880 | if (dm_get_device(ti, argv[3], cc->start, ti->len, |
| 881 | dm_table_get_mode(ti->table), &cc->dev)) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 882 | ti->error = "Device lookup failed"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | goto bad5; |
| 884 | } |
| 885 | |
| 886 | if (ivmode && cc->iv_gen_ops) { |
| 887 | if (ivopts) |
| 888 | *(ivopts - 1) = ':'; |
| 889 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); |
| 890 | if (!cc->iv_mode) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 891 | ti->error = "Error kmallocing iv_mode string"; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 892 | goto bad5; |
| 893 | } |
| 894 | strcpy(cc->iv_mode, ivmode); |
| 895 | } else |
| 896 | cc->iv_mode = NULL; |
| 897 | |
| 898 | ti->private = cc; |
| 899 | return 0; |
| 900 | |
| 901 | bad5: |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 902 | bioset_free(cc->bs); |
| 903 | bad_bs: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 904 | mempool_destroy(cc->page_pool); |
| 905 | bad4: |
| 906 | mempool_destroy(cc->io_pool); |
| 907 | bad3: |
| 908 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
| 909 | cc->iv_gen_ops->dtr(cc); |
| 910 | bad2: |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 911 | crypto_free_blkcipher(tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 912 | bad1: |
Stefan Rompf | 9d3520a | 2006-01-06 00:20:08 -0800 | [diff] [blame] | 913 | /* Must zero key material before freeing */ |
| 914 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 915 | kfree(cc); |
| 916 | return -EINVAL; |
| 917 | } |
| 918 | |
| 919 | static void crypt_dtr(struct dm_target *ti) |
| 920 | { |
| 921 | struct crypt_config *cc = (struct crypt_config *) ti->private; |
| 922 | |
Milan Broz | 6a24c71 | 2006-10-03 01:15:40 -0700 | [diff] [blame] | 923 | bioset_free(cc->bs); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 924 | mempool_destroy(cc->page_pool); |
| 925 | mempool_destroy(cc->io_pool); |
| 926 | |
Jesper Juhl | 990a8ba | 2005-06-21 17:17:30 -0700 | [diff] [blame] | 927 | kfree(cc->iv_mode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 928 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
| 929 | cc->iv_gen_ops->dtr(cc); |
Herbert Xu | d1806f6 | 2006-08-22 20:29:17 +1000 | [diff] [blame] | 930 | crypto_free_blkcipher(cc->tfm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | dm_put_device(ti, cc->dev); |
Stefan Rompf | 9d3520a | 2006-01-06 00:20:08 -0800 | [diff] [blame] | 932 | |
| 933 | /* Must zero key material before freeing */ |
| 934 | memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | kfree(cc); |
| 936 | } |
| 937 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 938 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
| 939 | union map_info *map_context) |
| 940 | { |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 941 | struct crypt_config *cc = ti->private; |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 942 | struct dm_crypt_io *io; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 943 | |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 944 | io = mempool_alloc(cc->io_pool, GFP_NOIO); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 945 | io->target = ti; |
Milan Broz | 8b00445 | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 946 | io->base_bio = bio; |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 947 | io->error = io->post_process = 0; |
Milan Broz | 93e605c | 2006-10-03 01:15:38 -0700 | [diff] [blame] | 948 | atomic_set(&io->pending, 0); |
Milan Broz | 23541d2 | 2006-10-03 01:15:39 -0700 | [diff] [blame] | 949 | kcryptd_queue_io(io); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 950 | |
Kiyoshi Ueda | d2a7ad2 | 2006-12-08 02:41:06 -0800 | [diff] [blame] | 951 | return DM_MAPIO_SUBMITTED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 952 | } |
| 953 | |
| 954 | static int crypt_status(struct dm_target *ti, status_type_t type, |
| 955 | char *result, unsigned int maxlen) |
| 956 | { |
| 957 | struct crypt_config *cc = (struct crypt_config *) ti->private; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 958 | unsigned int sz = 0; |
| 959 | |
| 960 | switch (type) { |
| 961 | case STATUSTYPE_INFO: |
| 962 | result[0] = '\0'; |
| 963 | break; |
| 964 | |
| 965 | case STATUSTYPE_TABLE: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | if (cc->iv_mode) |
Christophe Saout | 37af656 | 2006-10-30 20:39:08 +0100 | [diff] [blame] | 967 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
| 968 | cc->iv_mode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | else |
Christophe Saout | 37af656 | 2006-10-30 20:39:08 +0100 | [diff] [blame] | 970 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 971 | |
| 972 | if (cc->key_size > 0) { |
| 973 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) |
| 974 | return -ENOMEM; |
| 975 | |
| 976 | crypt_encode_key(result + sz, cc->key, cc->key_size); |
| 977 | sz += cc->key_size << 1; |
| 978 | } else { |
| 979 | if (sz >= maxlen) |
| 980 | return -ENOMEM; |
| 981 | result[sz++] = '-'; |
| 982 | } |
| 983 | |
Andrew Morton | 4ee218c | 2006-03-27 01:17:48 -0800 | [diff] [blame] | 984 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
| 985 | cc->dev->name, (unsigned long long)cc->start); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 986 | break; |
| 987 | } |
| 988 | return 0; |
| 989 | } |
| 990 | |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 991 | static void crypt_postsuspend(struct dm_target *ti) |
| 992 | { |
| 993 | struct crypt_config *cc = ti->private; |
| 994 | |
| 995 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); |
| 996 | } |
| 997 | |
| 998 | static int crypt_preresume(struct dm_target *ti) |
| 999 | { |
| 1000 | struct crypt_config *cc = ti->private; |
| 1001 | |
| 1002 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { |
| 1003 | DMERR("aborting resume - crypt key is not set."); |
| 1004 | return -EAGAIN; |
| 1005 | } |
| 1006 | |
| 1007 | return 0; |
| 1008 | } |
| 1009 | |
| 1010 | static void crypt_resume(struct dm_target *ti) |
| 1011 | { |
| 1012 | struct crypt_config *cc = ti->private; |
| 1013 | |
| 1014 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); |
| 1015 | } |
| 1016 | |
| 1017 | /* Message interface |
| 1018 | * key set <key> |
| 1019 | * key wipe |
| 1020 | */ |
| 1021 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) |
| 1022 | { |
| 1023 | struct crypt_config *cc = ti->private; |
| 1024 | |
| 1025 | if (argc < 2) |
| 1026 | goto error; |
| 1027 | |
| 1028 | if (!strnicmp(argv[0], MESG_STR("key"))) { |
| 1029 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { |
| 1030 | DMWARN("not suspended during key manipulation."); |
| 1031 | return -EINVAL; |
| 1032 | } |
| 1033 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) |
| 1034 | return crypt_set_key(cc, argv[2]); |
| 1035 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) |
| 1036 | return crypt_wipe_key(cc); |
| 1037 | } |
| 1038 | |
| 1039 | error: |
| 1040 | DMWARN("unrecognised message received."); |
| 1041 | return -EINVAL; |
| 1042 | } |
| 1043 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1044 | static struct target_type crypt_target = { |
| 1045 | .name = "crypt", |
Ludwig Nussel | 46b4773 | 2007-05-09 02:32:55 -0700 | [diff] [blame] | 1046 | .version= {1, 5, 0}, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1047 | .module = THIS_MODULE, |
| 1048 | .ctr = crypt_ctr, |
| 1049 | .dtr = crypt_dtr, |
| 1050 | .map = crypt_map, |
| 1051 | .status = crypt_status, |
Milan Broz | e48d4bb | 2006-10-03 01:15:37 -0700 | [diff] [blame] | 1052 | .postsuspend = crypt_postsuspend, |
| 1053 | .preresume = crypt_preresume, |
| 1054 | .resume = crypt_resume, |
| 1055 | .message = crypt_message, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1056 | }; |
| 1057 | |
| 1058 | static int __init dm_crypt_init(void) |
| 1059 | { |
| 1060 | int r; |
| 1061 | |
Alasdair G Kergon | 028867a | 2007-07-12 17:26:32 +0100 | [diff] [blame] | 1062 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1063 | if (!_crypt_io_pool) |
| 1064 | return -ENOMEM; |
| 1065 | |
| 1066 | _kcryptd_workqueue = create_workqueue("kcryptd"); |
| 1067 | if (!_kcryptd_workqueue) { |
| 1068 | r = -ENOMEM; |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 1069 | DMERR("couldn't create kcryptd"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | goto bad1; |
| 1071 | } |
| 1072 | |
| 1073 | r = dm_register_target(&crypt_target); |
| 1074 | if (r < 0) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 1075 | DMERR("register failed %d", r); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1076 | goto bad2; |
| 1077 | } |
| 1078 | |
| 1079 | return 0; |
| 1080 | |
| 1081 | bad2: |
| 1082 | destroy_workqueue(_kcryptd_workqueue); |
| 1083 | bad1: |
| 1084 | kmem_cache_destroy(_crypt_io_pool); |
| 1085 | return r; |
| 1086 | } |
| 1087 | |
| 1088 | static void __exit dm_crypt_exit(void) |
| 1089 | { |
| 1090 | int r = dm_unregister_target(&crypt_target); |
| 1091 | |
| 1092 | if (r < 0) |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 1093 | DMERR("unregister failed %d", r); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1094 | |
| 1095 | destroy_workqueue(_kcryptd_workqueue); |
| 1096 | kmem_cache_destroy(_crypt_io_pool); |
| 1097 | } |
| 1098 | |
| 1099 | module_init(dm_crypt_init); |
| 1100 | module_exit(dm_crypt_exit); |
| 1101 | |
| 1102 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); |
| 1103 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); |
| 1104 | MODULE_LICENSE("GPL"); |