Re: [TLS] SCSV vs RI when both specified - consensus?

Marsh Ray <marsh@extendedsubset.com> Mon, 21 December 2009 18:46 UTC

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Date: Mon, 21 Dec 2009 12:46:41 -0600
From: Marsh Ray <marsh@extendedsubset.com>
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To: Nasko Oskov <noskov@microsoft.com>
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Subject: Re: [TLS] SCSV vs RI when both specified - consensus?
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Nasko Oskov wrote:
> Marsh Ray wrote:
>>> A server receiving a Client Hello containing multiple RI extensions 
>>> MUST generate a fatal "decode_error" alert and terminate the 
>>> connection. A server receiving a Client Hello containing the SCSV and 
>>> an RI extension is to interpret the RI as usual and ignore the SCSV.
> 
> I generally agree with this wording. I find the sentence describing multiple
> RI extensions behavior redundand, since this is already part of RFC5246:
> 
> Section 7.4.1.4:
>     There MUST NOT be more than one extension of the same type.

Oh yeah. It's also in RFC 3546 'TLS Extensions'. I looked for it the
other day but didn't see it. Now I can't find where it says what to do
when it happens.

- Marsh