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Subject: Re: [PATCH v2] crypto: aesni - add ccm(aes) algorithm implementation
To:     Herbert Xu <herbert@gondor.apana.org.au>,
        Ard Biesheuvel <ardb@kernel.org>
Cc:     Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Steve deRosier <derosier@cal-sierra.com>
References: <20201201194556.5220-1-ardb@kernel.org>
 <20201201215722.GA31941@gondor.apana.org.au>
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 <20201201220431.GA32072@gondor.apana.org.au>
From:   Ben Greear <greearb@candelatech.com>
Organization: Candela Technologies
Message-ID: <acdaf933-e7a3-e30b-28c3-a324fe957979@candelatech.com>
Date:   Tue, 1 Dec 2020 14:12:34 -0800
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On 12/1/20 2:04 PM, Herbert Xu wrote:
> On Tue, Dec 01, 2020 at 11:01:57PM +0100, Ard Biesheuvel wrote:
>>
>> This is not the first time this has come up. The point is that CCMP in
>> the wireless stack is not used in 99% of the cases, given that any
>> wifi hardware built in the last ~10 years can do it in hardware. Only
>> in exceptional cases, such as Ben's, is there a need for exercising
>> this interface.
> 
> Either it matters or it doesn't.  If it doesn't matter why are we
> having this dicussion at all? If it does then fixing just one
> direction makes no sense.
> 
>> Also, care to explain why we have synchronous AEADs in the first place
>> if they are not supposed to be used?
> 
> Sync AEADs would make sense if you were dealing with a very small
> amount of data, e.g., one block.

Sure, I bet some part of the kernel does this.  So let the patch in to
handle that case.  It will just be happy luck that it improves some other
problems as well.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com