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Date:   Tue, 30 Aug 2022 17:00:13 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Ignat Korchagin <ignat@cloudflare.com>
Cc:     "David S . Miller" <davem@davemloft.net>,
        linux-crypto <linux-crypto@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        kernel-team <kernel-team@cloudflare.com>
Subject: Re: [PATCH] crypto: akcipher - default implementations for setting
 private/public keys
Message-ID: <Yw3Rneo6Ik1QEfbG@gondor.apana.org.au>
References: <20220729165954.991-1-ignat@cloudflare.com>
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On Mon, Aug 29, 2022 at 11:48:23AM +0100, Ignat Korchagin wrote:
>
> I can only elaborate here as I didn't encounter any real-world
> use-cases, but may assume some limited crypto hardware device, which
> may somehow "encourage" doing public key operations in software and
> providing only "private-key" operations due to its limited resources.

In general if a hardware is missing a piece of the functinoality
required by the API then it should implement a software fallback.

The only time such a NULL helper would make sense if an algorithm
had no public key.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt