Messages in this thread | | | Date | Sat, 21 Feb 2004 12:36:57 -0500 | From | Jean-Luc Cooke <> | Subject | Re: dm-crypt, new IV and standards |
| |
On Sat, Feb 21, 2004 at 11:48:21AM -0500, Jean-Luc Cooke wrote: > > Please focus your recommendations on security, not backward compatibility > > with something that is new to the kernel tree, broken and maintainerless.
> I'll start writing OMAC now.
FYI OMAC spec: http://crypt.cis.ibaraki.ac.jp/omac/omac.html
As you can see, there is a fixed output no matter how large the input it, the output is always 128 bits.
So how will this fit into the cipher.c interface?
case CRYPTO_TFM_MODE_CTR: ops->cit_encrypt = omac_compute; ops->cit_decrypt = nocrypt; ops->cit_encrypt_iv = nocrypt_iv; ops->cit_decrypt_iv = nocrypt_iv; break;
But now the user will have to call cit_encrypt(tfm, dst[0], src[i], nbytes); Notice how dest will always have to be dst[0]. Unless we use the hash interface.
Thoughts?
static int omac_encrypt(struct crypto_tfm *tfm, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { return crypt(tfm, dst, src, nbytes, tfm->__crt_alg->cra_cipher.cia_encrypt, omac_process, 1, tfm->crt_cipher.cit_iv); }
JLC - has CTR mode implemented and will post once he has OMAC done as well.
-- http://www.certainkey.com Suite 4560 CTTC 1125 Colonel By Dr. Ottawa ON, K1S 5B6 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |