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Message-ID: <3740c569-9dd2-448d-bcac-16ca5203b206@linux.ibm.com>
Date: Mon, 4 Mar 2024 14:01:38 -0500
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v4 00/12] Add support for NIST P521 to ecdsa
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To: Lukas Wunner <lukas@wunner.de>
Cc: keyrings@vger.kernel.org, linux-crypto@vger.kernel.org,
        herbert@gondor.apana.org.au, davem@davemloft.net,
        linux-kernel@vger.kernel.org, saulo.alessandre@tse.jus.br
References: <20240301022007.344948-1-stefanb@linux.ibm.com>
 <20240304181004.GA14180@wunner.de>
From: Stefan Berger <stefanb@linux.ibm.com>
In-Reply-To: <20240304181004.GA14180@wunner.de>
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On 3/4/24 13:10, Lukas Wunner wrote:
> On Thu, Feb 29, 2024 at 09:19:55PM -0500, Stefan Berger wrote:
>> This series adds support for the NIST P521 curve to the ecdsa module
>> to enable signature verification with it.
>>
>> An issue with the current code in ecdsa is that it assumes that input
>> arrays providing key coordinates for example, are arrays of digits
>> (a 'digit' is a 'u64'). This works well for all currently supported
>> curves, such as NIST P192/256/384, but does not work for NIST P521 where
>> coordinates are 8 digits + 2 bytes long. So some of the changes deal with
>> converting byte arrays to digits and adjusting tests on input byte
>> array lengths to tolerate arrays not providing multiples of 8 bytes.
> 
> When respinning this series as v5, feel free to add my
> 
> Tested-by: Lukas Wunner <lukas@wunner.de>

Thanks.
> 
> 
> I cherry-picked the commits from your nist_p521.v5 branch...
> 
> https://github.com/stefanberger/linux-ima-namespaces/commits/nist_p521.v5/
> 
> ...onto my development branch for PCI device authentication...
> 
> https://github.com/l1k/linux/commits/doe
> 
> ...and tested against qemu+libspdm that an emulated NVMe drive
> is able to present a valid signature using NIST P521 + SHA384
> which can be verified correctly by the kernel.

FYI: I have a PR for a test suite here as well:

https://github.com/stefanberger/eckey-testing/pull/1

> 
> I needed to fix up two of my patches, one which adds P1363
> signature format support to the kernel and another fixup to
> add NIST P521 support to the in-kernel SPDM library
> (two top-most commits on my above-linked development branch).
> 
> I performed this test against your f81547267725 head and notice
> that you pushed a new version today (with "curve->nbits == 521"
> instead of strcmp), but I'm confident those two small changes
> wouldn't alter the outcone, hence my Tested-by stands.
> 
> Thanks,
> 
> Lukas
>