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Re: [DNSOP] A draft about the Name:Wreck problem draft-dashevskyi-dnsrr-antipatterns

Tony Finch <dot@dotat.at> Wed, 14 April 2021 21:17 UTC

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Date: Wed, 14 Apr 2021 22:17:32 +0100
From: Tony Finch <dot@dotat.at>
To: John Levine <johnl@taugh.com>
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Subject: Re: [DNSOP] A draft about the Name:Wreck problem draft-dashevskyi-dnsrr-antipatterns
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John Levine <johnl@taugh.com> wrote:
>
> On the other hand, all of the sloppy coding people use to handle
> compressed names is embarassing.

I don't think it's entirely fair to blame the coders who make these
mistakes, because a very large number of excellent programmers have made a
mess of DNS name decompression. When I find out about new DNS code the
first thing I do is look at the name parser to see if it successfully
avoids these traps and pitfalls, because it's a good indication that the
programmer has learned from their own or others' mistakes, or has much
greater than average ability to write attack-resistant parsers.

It seems worthwhile to try to help future coders not to mess it up.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  https://dotat.at/
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