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Subject: Re: [PATCH 19/22] crypto: inside-secure - add check for xts input
 length equal to zero
To:     Herbert Xu <herbert@gondor.apana.org.au>,
        "Van Leeuwen, Pascal" <pvanleeuwen@rambus.com>
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        Andrei Botila <andrei.botila@nxp.com>,
        Antoine Tenart <antoine.tenart@bootlin.com>
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On 8/10/2020 4:45 PM, Herbert Xu wrote:
> On Mon, Aug 10, 2020 at 10:20:20AM +0000, Van Leeuwen, Pascal wrote:
>>
>> With all due respect, but this makes no sense.
> 
> I agree.  This is a lot of churn for no gain.
> 
I would say the gain is that all skcipher algorithms would behave the same
when input length equals zero - i.e. treat the request as a no-op.

We can't say "no input" has any meaning to the other skcipher algorithms,
but the convention is to accept this case and just return 0.
I don't see why XTS has to be handled differently.

Thanks,
Horia