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From:   Stephan Mueller <smueller@chronox.de>
To:     Mahmoud Adam <mngyadam@amazon.com>,
        Herbert Xu <herbert@gondor.apana.org.au>
Cc:     davem@davemloft.net, linux-crypto@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] crypto: rsa - allow only odd e and restrict value in FIPS mode
Date:   Wed, 14 Jun 2023 13:59:23 +0200
Message-ID: <4502349.tsrQG4AIub@tauon.chronox.de>
In-Reply-To: <ZImNfECCS+22oF/D@gondor.apana.org.au>
References: <20230613161731.74081-1-mngyadam@amazon.com>
 <ZImNfECCS+22oF/D@gondor.apana.org.au>
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Am Mittwoch, 14. Juni 2023, 11:50:52 CEST schrieb Herbert Xu:

Hi Herbert,

> On Tue, Jun 13, 2023 at 04:17:31PM +0000, Mahmoud Adam wrote:
> > check if rsa public exponent is odd and check its value is between
> > 2^16 < e < 2^256.
> > 
> > FIPS 186-5 DSS (page 35)[1] specify that:
> > 
> > 1. The public exponent e shall be selected with the following constraints:
> >   (a) The public verification exponent e shall be selected prior to
> >   generating the primes, p and q, and the private signature exponent
> >   d.
> >   
> >   (b) The exponent e shall be an odd positive integer such that:
> >    2^16 < e < 2^256.
> > 
> > [1] https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-5.pdf
> > 
> > Signed-off-by: Mahmoud Adam <mngyadam@amazon.com>

Reviewed-by: Stephan Mueller <smueller@chronox.de>

Ciao
Stephan