[EXT] Re: [PATCH v0 3/8] crypto: hbk flags & info added to the tfm

[Pankaj Gupta]

> -----Original Message-----
> From: Herbert Xu <herbert at gondor.apana.org.au>
> Sent: Tuesday, October 11, 2022 2:34 PM
> To: Jason A. Donenfeld <Jason at zx2c4.com>
> Cc: Pankaj Gupta <pankaj.gupta at nxp.com>; jarkko at kernel.org;
> a.fatoum at pengutronix.de; gilad at benyossef.com; jejb at linux.ibm.com;
> zohar at linux.ibm.com; dhowells at redhat.com; sumit.garg at linaro.org;
> david at sigma-star.at; michael at walle.cc; john.ernberg at actia.se;
> jmorris at namei.org; serge at hallyn.com; davem at davemloft.net;
> j.luebbe at pengutronix.de; ebiggers at kernel.org; richard at nod.at;
> keyrings at vger.kernel.org; linux-crypto at vger.kernel.org; linux-
> integrity at vger.kernel.org; linux-kernel at vger.kernel.org; linux-security-
> module at vger.kernel.org; Sahil Malhotra <sahil.malhotra at nxp.com>; Kshitiz
> Varshney <kshitiz.varshney at nxp.com>; Horia Geanta
> <horia.geanta at nxp.com>; Varun Sethi <V.Sethi at nxp.com>
> Subject: Re: [EXT] Re: [PATCH v0 3/8] crypto: hbk flags & info added to the
> tfm
> 
> Caution: EXT Email
> 
> On Mon, Oct 10, 2022 at 09:15:48AM -0600, Jason A. Donenfeld wrote:
> >
> > Do you mean to say that other drivers that use hardware-backed keys do
> > so by setting "cra_name" to something particular? Like instead of "aes"
> > it'd be "aes-but-special-for-this-driver"? If so, that would seem to
> > break the design of the crypto API. Which driver did you see that does
> > this? Or perhaps, more generally, what are the drivers that Herbert is
> > talking about when he mentions the "plenty of existing drivers" that
> > already do this?
> 
> Grep for paes for the existing drivers that support this.  I don't have anything
> against this feature per se, but the last thing we want is a proliferation of
> different ways of doing the same thing.

Our goal is to have a generic solution, which can be extended to any driver dealing with:
- Generating HBK and adding to trusted keyring.
- Using the trusted keyring's HBK for crypto operation.

With this framework in place, driver specific custom changes can be avoided, bridging the interface-gap of:
kernel-keyring <-> kernel-crypto-layer.

Thanks.
> 
> Cheers,
> --
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