Subject: Re: [PATCH 17/18] crypto: dh - try to match domain parameters to a
 known safe-prime group
To:     Nicolai Stange <nstange@suse.de>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>
Cc:     =?UTF-8?Q?Stephan_M=c3=bcller?= <smueller@chronox.de>,
        Torsten Duwe <duwe@suse.de>, Zaibo Xu <xuzaibo@huawei.com>,
        Giovanni Cabiddu <giovanni.cabiddu@intel.com>,
        David Howells <dhowells@redhat.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        qat-linux@intel.com, keyrings@vger.kernel.org
References: <20211201004858.19831-1-nstange@suse.de>
 <20211201004858.19831-18-nstange@suse.de>
From:   Hannes Reinecke <hare@suse.de>
Message-ID: <1d8eb859-1d41-32e1-98b8-3ddd60e2e0ab@suse.de>
Date:   Wed, 1 Dec 2021 08:34:16 +0100
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On 12/1/21 1:48 AM, Nicolai Stange wrote:
> A subsequent patch will make the DH implementation to reject any input
> domain parameter set with ->group_id == dh_group_id_unknown in FIPS mode.
> However, as the keyctl(KEYCTL_DH_COMPUTE) implementation simply passes
> forward keys from userspace, it does not (and cannot) set ->group_id to
> anything else than dh_group_id_unknown.
> 
> In order to still allow for keyctl(KEYCTL_DH_COMPUTE) to work on approved
> domain parameters passed in from userspace in FIPS mode, make
> crypto_dh_decode_key() to compare them against any of the known groups and
> set ->group_id upon having found a match, if any.
> 
> Signed-off-by: Nicolai Stange <nstange@suse.de>
> ---
>   crypto/dh_helper.c | 33 +++++++++++++++++++++++++++++++++
>   1 file changed, 33 insertions(+)
> 
Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                Kernel Storage Architect
hare@suse.de                              +49 911 74053 688
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