diff options
Diffstat (limited to 'drivers/md/dm-crypt.c')
| -rw-r--r-- | drivers/md/dm-crypt.c | 80 |
1 files changed, 67 insertions, 13 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 08a40f4e4f60..4c2471ee054a 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -20,6 +20,7 @@ #include <asm/atomic.h> #include <linux/scatterlist.h> #include <asm/page.h> +#include <asm/unaligned.h> #include "dm.h" @@ -85,7 +86,10 @@ struct crypt_config { */ struct crypt_iv_operations *iv_gen_ops; char *iv_mode; - struct crypto_cipher *iv_gen_private; + union { + struct crypto_cipher *essiv_tfm; + int benbi_shift; + } iv_gen_private; sector_t iv_offset; unsigned int iv_size; @@ -101,7 +105,7 @@ struct crypt_config { #define MIN_POOL_PAGES 32 #define MIN_BIO_PAGES 8 -static kmem_cache_t *_crypt_io_pool; +static struct kmem_cache *_crypt_io_pool; /* * Different IV generation algorithms: @@ -113,6 +117,9 @@ static kmem_cache_t *_crypt_io_pool; * encrypted with the bulk cipher using a salt as key. The salt * should be derived from the bulk cipher's key via hashing. * + * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 + * (needed for LRW-32-AES and possible other narrow block modes) + * * plumb: unimplemented, see: * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 */ @@ -191,21 +198,61 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, } kfree(salt); - cc->iv_gen_private = essiv_tfm; + cc->iv_gen_private.essiv_tfm = essiv_tfm; return 0; } static void crypt_iv_essiv_dtr(struct crypt_config *cc) { - crypto_free_cipher(cc->iv_gen_private); - cc->iv_gen_private = NULL; + crypto_free_cipher(cc->iv_gen_private.essiv_tfm); + cc->iv_gen_private.essiv_tfm = NULL; } static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) { memset(iv, 0, cc->iv_size); *(u64 *)iv = cpu_to_le64(sector); - crypto_cipher_encrypt_one(cc->iv_gen_private, iv, iv); + crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); + return 0; +} + +static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, + const char *opts) +{ + unsigned int bs = crypto_blkcipher_blocksize(cc->tfm); + int log = ilog2(bs); + + /* we need to calculate how far we must shift the sector count + * to get the cipher block count, we use this shift in _gen */ + + if (1 << log != bs) { + ti->error = "cypher blocksize is not a power of 2"; + return -EINVAL; + } + + if (log > 9) { + ti->error = "cypher blocksize is > 512"; + return -EINVAL; + } + + cc->iv_gen_private.benbi_shift = 9 - log; + + return 0; +} + +static void crypt_iv_benbi_dtr(struct crypt_config *cc) +{ +} + +static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) +{ + __be64 val; + + memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ + + val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); + put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); + return 0; } @@ -219,13 +266,18 @@ static struct crypt_iv_operations crypt_iv_essiv_ops = { .generator = crypt_iv_essiv_gen }; +static struct crypt_iv_operations crypt_iv_benbi_ops = { + .ctr = crypt_iv_benbi_ctr, + .dtr = crypt_iv_benbi_dtr, + .generator = crypt_iv_benbi_gen +}; static int crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out, struct scatterlist *in, unsigned int length, int write, sector_t sector) { - u8 iv[cc->iv_size]; + u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64)))); struct blkcipher_desc desc = { .tfm = cc->tfm, .info = iv, @@ -458,11 +510,11 @@ static void dec_pending(struct crypt_io *io, int error) * interrupt context. */ static struct workqueue_struct *_kcryptd_workqueue; -static void kcryptd_do_work(void *data); +static void kcryptd_do_work(struct work_struct *work); static void kcryptd_queue_io(struct crypt_io *io) { - INIT_WORK(&io->work, kcryptd_do_work, io); + INIT_WORK(&io->work, kcryptd_do_work); queue_work(_kcryptd_workqueue, &io->work); } @@ -618,9 +670,9 @@ static void process_read_endio(struct crypt_io *io) dec_pending(io, crypt_convert(cc, &ctx)); } -static void kcryptd_do_work(void *data) +static void kcryptd_do_work(struct work_struct *work) { - struct crypt_io *io = data; + struct crypt_io *io = container_of(work, struct crypt_io, work); if (io->post_process) process_read_endio(io); @@ -768,7 +820,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) cc->tfm = tfm; /* - * Choose ivmode. Valid modes: "plain", "essiv:<esshash>". + * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". * See comments at iv code */ @@ -778,6 +830,8 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) cc->iv_gen_ops = &crypt_iv_plain_ops; else if (strcmp(ivmode, "essiv") == 0) cc->iv_gen_ops = &crypt_iv_essiv_ops; + else if (strcmp(ivmode, "benbi") == 0) + cc->iv_gen_ops = &crypt_iv_benbi_ops; else { ti->error = "Invalid IV mode"; goto bad2; @@ -908,7 +962,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio, atomic_set(&io->pending, 0); kcryptd_queue_io(io); - return 0; + return DM_MAPIO_SUBMITTED; } static int crypt_status(struct dm_target *ti, status_type_t type, |