2017-01-13 11:41 GMT+01:00 Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>: > On Thu, Jan 12, 2017 at 01:59:52PM +0100, Ondrej Mosnacek wrote: >> the goal of this patchset is to allow those skcipher API users that need to >> process batches of small messages (especially dm-crypt) to do so efficiently. > > Please explain why this can't be done with the existing framework > using IV generators similar to the ones used for IPsec. As I already mentioned in another thread, there are basically two reasons: 1) Milan would like to add authenticated encryption support to dm-crypt (see [1]) and as part of this change, a new random IV mode would be introduced. This mode generates a random IV for each sector write, includes it in the authenticated data and stores it in the sector's metadata (in a separate part of the disk). In this case dm-crypt will need to have control over the IV generation (or at least be able to somehow retrieve it after the crypto operation... but passing RNG responsibility to drivers doesn't seem to be a good idea anyway). 2) With this API, drivers wouldn't have to provide implementations for specific IV generation modes, and just implement bulk requests for the common modes/algorithms (XTS, CBC, ...) while still getting performance benefit. Regards, Ondrej [1] https://www.redhat.com/archives/dm-devel/2017-January/msg00028.html > > Thanks, > -- > Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Home Page: http://gondor.apana.org.au/~herbert/ > PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
