Date:   Wed, 12 Jan 2022 10:35:38 -0800
From:   Eric Biggers <ebiggers@kernel.org>
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     linux-crypto@vger.kernel.org, netdev@vger.kernel.org,
        wireguard@lists.zx2c4.com, linux-kernel@vger.kernel.org,
        bpf@vger.kernel.org, geert@linux-m68k.org, tytso@mit.edu,
        gregkh@linuxfoundation.org, jeanphilippe.aumasson@gmail.com,
        ardb@kernel.org, Herbert Xu <herbert@gondor.apana.org.au>
Subject: Re: [PATCH crypto 2/2] lib/crypto: blake2s: move hmac construction
 into wireguard
Message-ID: <Yd8fevK3n5aACJMF@gmail.com>
References: <CAHmME9qbnYmhvsuarButi6s=58=FPiti0Z-QnGMJ=OsMzy1eOg@mail.gmail.com>
 <20220111134934.324663-1-Jason@zx2c4.com>
 <20220111134934.324663-3-Jason@zx2c4.com>
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On Tue, Jan 11, 2022 at 02:49:34PM +0100, Jason A. Donenfeld wrote:
> Basically nobody should use blake2s in an HMAC construction; it already
> has a keyed variant. But for unfortunately historical reasons, Noise,
> used by WireGuard, uses HKDF quite strictly, which means we have to use
> this. Because this really shouldn't be used by others, this commit moves
> it into wireguard's noise.c locally, so that kernels that aren't using
> WireGuard don't get this superfluous code baked in. On m68k systems,
> this shaves off ~314 bytes.
> 
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Herbert Xu <herbert@gondor.apana.org.au>
> Cc: Ard Biesheuvel <ardb@kernel.org>
> Cc: netdev@vger.kernel.org
> Cc: wireguard@lists.zx2c4.com
> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
> ---

Reviewed-by: Eric Biggers <ebiggers@google.com>

- Eric