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Re: [DNSOP] [secdir] Secdir last call review of draft-ietf-dnsop-server-cookies-04

Ondřej Surý <ondrej@isc.org> Wed, 02 December 2020 22:18 UTC

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From: Ondřej Surý <ondrej@isc.org>
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Date: Wed, 02 Dec 2020 23:18:29 +0100
Cc: Stephen Farrell <stephen.farrell@cs.tcd.ie>, last-call@ietf.org, draft-ietf-dnsop-server-cookies.all@ietf.org, dnsop WG <dnsop@ietf.org>, secdir@ietf.org
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To: Eric Rescorla <ekr@rtfm.com>
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Subject: Re: [DNSOP] [secdir] Secdir last call review of draft-ietf-dnsop-server-cookies-04
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SYN cookies in both Linux and FreeBSD uses siphash.

* FreeBSD: https://svnweb.freebsd.org/base?view=revision&revision=253210 (since 2013)
* Linux: https://github.com/torvalds/linux/commit/fe62d05b295bde037fa324767674540907c89362#diff-14feef60c3dbcf67539f089de04546c907233cbae09e1b2dd2c2bc6d6eae4416 (since 2017)

I believe that the SYN cookies have exactly the same properties as DNS cookies.

Ondrej
--
Ondřej Surý (He/Him)
ondrej@isc.org

> On 2. 12. 2020, at 22:15, Eric Rescorla <ekr@rtfm.com> wrote:
> 
> Well hash tables are an application with somewhat different security properties than MACs, so I don't think this is dispositive.
>

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