From: Stephan Mueller <smueller@chronox.de>
Subject: Re: [PATCH] crypto: implement DH primitives under akcipher API
Date: Tue, 01 Mar 2016 12:17:15 +0100
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Cc: tadeusz.struk@intel.com, linux-crypto@vger.kernel.org,
	herbert@gondor.apana.org.au
To: Salvatore Benedetto <salvatore.benedetto@intel.com>
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Am Dienstag, 1. M=E4rz 2016, 11:08:34 schrieb Salvatore Benedetto:

Hi Salvatore,

> > > +static int dh_check_params_length(unsigned int p_len)
> > > +{
> > > +	switch (p_len) {
> > > +	case 768:
> > > +	case 1024:
> > > +	case 1536:
> > > +	case 2048:
> > > +	case 3072:
> > > +	case 4096:
> > > +		return 0;
> > > +	}
> > > +	return -EINVAL;
> > > +}
> >=20
> > What is the reason for restricting the size to 4096?
>=20
> Honestly no reason.
> Could not find restrictions in the spec about the params length.

I am just wondering because other DH impls allow longer sizes.

And besides, I would like to disallow all < 2048 right from the start.
>=20
> > > +
> > > +static int dh_no_op(struct akcipher_request *req)
> > > +{
> > > +	return -ENOPROTOOPT;
> > > +}
> > > +
> > > +static int dh_set_priv_key(struct crypto_akcipher *tfm, const vo=
id
> > > *key,
> > > +			   unsigned int keylen)
> > > +{
> > > +	struct dh_params *params =3D akcipher_tfm_ctx(tfm);
> >=20
> > dh_get_params?
>=20
> You mean adding a helper function? OK.

Not adding, but using your helper function -- why do you have it there =
in the=20
first place? :-)

Ciao
Stephan