Re: [DNSOP] Review of draft-ietf-dnsop-rfc2845bis-02.txt

Ray Bellis <ray@bellis.me.uk> Tue, 20 November 2018 11:42 UTC

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From: Ray Bellis <ray@bellis.me.uk>
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Subject: Re: [DNSOP] Review of draft-ietf-dnsop-rfc2845bis-02.txt
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On 19/11/2018 13:45, Mukund Sivaraman wrote:

> Soon after this TSIG authentication bypass attack was reported, during a
> review of the BIND TSIG implementation by Ray Bellis and me, we found a
> couple of other issues. One of them is not a real-world issue (to do
> with under-specification of what to do with full MAC length having
> non-integral number of octets - there are no such common HMACs
> currently), and another that I'm not able to remember that had to do
> with an off-by-1 (or something similar) on the fudge and time signed
> fields. Do you have any recollection of it Ray?

I vaguely recall the discussion but not the detail of it.

ISTR it was something to do with using a <= comparison rather than <, or 
vice versa.

Ray