On Tue, Jun 14, 2016 at 02:36:54PM +0000, Benedetto, Salvatore wrote:
>
> My very first patch used PKCS3 and there were some objections to that.
> https://patchwork.kernel.org/patch/8311881/
>
> Both Bluetooth or keyctl KEYCTL_DH_COMPUTE would have to first pack the
> key to whatever format we choose and I don't see that very convinient. We
> only want to provide the acceleration here, without bounding the user to a
> certain key format.
Have you looked at the rtnetlink encoding used by authenc.c? It is
much more light-weight. There is no need to depend on ASN.1 parsers
at all.
To make it even easier for users such as bluetooth, you can create
helpers that convert struct dh to a byte stream, and vice versa.
For example, the interface could look like this:
struct dh key;
char *buf;
unsigned int len;
/* init key */
key = ...;
len = crypto_dh_key_len(&key);
buf = kmalloc(len, GFP_KERNEL);
if (!buf)
...;
crypto_dh_encode_key(buf, len, &key);
crypto_kpp_set_secret(tfm, buf, len);
The driver would do:
set_secret(char *buf, unsigned int len)
{
struct dh key;
int err;
err = crypto_dh_decode_key(buf, len, &key);
...
> akcipher is different as PKCS1 is a recognized standard for RSA keys.
>
> Please don't get me wrong, it's not much of an issue for me to respin the
> patchset and change that to PKCS3 for example, but I see no harm in leaving
> it as it is and moving the key check format to whatever upper layer is using
> us
> (like BT and keyctl). Just more work for who is using the API.
>
> Could you reconsider that?
I'm sorry but using a void * for this is not acceptable. We're
talking about a data structure that comes from arbitrary users
and then has to be decoded by random drivers. It's something
totally different compared to a limited environment where the
same author is writing the code that creates and consumes the
pointer.
Throwing random void pointers at drivers is not a good idea.
Thanks,
--
Email: Herbert Xu <[email protected]>
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 [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
