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Subject: Re: [PATCH 0/2] nfsd: add principal to the data being tracked by
 nfsdcld
From:   Simo Sorce <simo@redhat.com>
To:     Scott Mayhew <smayhew@redhat.com>
Cc:     Chuck Lever <chuck.lever@oracle.com>,
        Bruce Fields <bfields@fieldses.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Date:   Wed, 04 Sep 2019 20:50:01 -0400
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On Wed, 2019-09-04 at 16:58 -0400, Scott Mayhew wrote:
> > While thinking about this I wondered, why not simply hash (SHA-256 for
> > example) the principal name and store the hash instead?
> > 
> > It will make the length fixed and uniform and probably often shorter
> > than the real principal names, so saving space in the general case.
> > 
> > I am not against truncating to 1024, but a hash would be more elegant
> > and correct.
> 
> I can do that.  Is there any reason I would want to convert the hash to
> to a human-readable format (i.e. something that would match the
> sha256sum command-line tool's output) or can I just use the raw buffer?
> Note that if we wanted to print the hash in an error message or
> something, I can just use printk's %*phN format specifier...

I do not see a reason to waste time turning to ascii before the time
you really need to. A byte buffer is perfectly fine.

Simo.

-- 
Simo Sorce
RHEL Crypto Team
Red Hat, Inc