dm crypt: add null iv

Add a new IV generation method 'null' to read old filesystem images created
with SuSE's loop_fish2 module.

Signed-off-by: Ludwig Nussel <ludwig.nussel@suse.de>
Acked-By: Christophe Saout <christophe@saout.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ludwig Nussel 2007-05-09 02:32:55 -07:00 committed by Linus Torvalds
parent f97380bcad
commit 46b477306a
1 changed files with 17 additions and 1 deletions

View File

@ -121,6 +121,9 @@ static void clone_init(struct crypt_io *, struct bio *);
* benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
* (needed for LRW-32-AES and possible other narrow block modes)
*
* null: the initial vector is always zero. Provides compatibility with
* obsolete loop_fish2 devices. Do not use for new devices.
*
* plumb: unimplemented, see:
* http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
*/
@ -257,6 +260,13 @@ static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
return 0;
}
static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
{
memset(iv, 0, cc->iv_size);
return 0;
}
static struct crypt_iv_operations crypt_iv_plain_ops = {
.generator = crypt_iv_plain_gen
};
@ -273,6 +283,10 @@ static struct crypt_iv_operations crypt_iv_benbi_ops = {
.generator = crypt_iv_benbi_gen
};
static struct crypt_iv_operations crypt_iv_null_ops = {
.generator = crypt_iv_null_gen
};
static int
crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out,
struct scatterlist *in, unsigned int length,
@ -803,6 +817,8 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
cc->iv_gen_ops = &crypt_iv_essiv_ops;
else if (strcmp(ivmode, "benbi") == 0)
cc->iv_gen_ops = &crypt_iv_benbi_ops;
else if (strcmp(ivmode, "null") == 0)
cc->iv_gen_ops = &crypt_iv_null_ops;
else {
ti->error = "Invalid IV mode";
goto bad2;
@ -1030,7 +1046,7 @@ error:
static struct target_type crypt_target = {
.name = "crypt",
.version= {1, 3, 0},
.version= {1, 5, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,