Alasdair G Kergon wrote: > On Wed, Feb 28, 2007 at 03:47:54PM +0100, Ludwig Nussel wrote: > > Any comments/objections on the patch? Is there any additional action > > from my side required to get this into the mainline kernel? > > This comment ought to be more descriptive: > > null: For mounting legacy images only. Ok, patch with better comment included. > I'll include it in the next set of patches I send upstream. Thanks! :-) Add IV generation method 'null' to be able to read old filesystem images created with SuSE's loop_fish2 module. Signed-off-by: Ludwig Nussel <ludwig.nussel@xxxxxxx> Acked-By: Christophe Saout <christophe@xxxxxxxx> --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -103,6 +103,10 @@ 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. * + * null: the initial vector is always zero. This method is for + * compatability with SuSE's obsolete loop_fish2 only. Do not + * use it for creating new content. + * * plumb: unimplemented, see: * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 */ @@ -203,6 +207,13 @@ static int crypt_iv_essiv_gen(struct cry 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 }; @@ -213,6 +224,9 @@ static struct crypt_iv_operations crypt_ .generator = crypt_iv_essiv_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, @@ -594,6 +608,8 @@ static int crypt_ctr(struct dm_target *t 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, "null") == 0) + cc->iv_gen_ops = &crypt_iv_null_ops; else { ti->error = "Invalid IV mode"; goto bad2; cu Ludwig -- (o_ Ludwig Nussel //\ SUSE Labs V_/_ http://www.suse.de/ SUSE LINUX Products GmbH, GF: Markus Rex, HRB 16746 (AG Nuernberg) -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
