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Re: [TLS] DSS with other than SHA-1 algorithms

Peter Gutmann <pgut001@cs.auckland.ac.nz> Wed, 13 April 2011 06:20 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: ekr@rtfm.com, pgut001@cs.auckland.ac.nz
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Date: Wed, 13 Apr 2011 18:20:04 +1200
Cc: simon@josefsson.org, geoffk@geoffk.org, tls@ietf.org
Subject: Re: [TLS] DSS with other than SHA-1 algorithms
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Eric Rescorla <ekr@rtfm.com> writes:

>1. I'm not convinced that the requirement that relying parties check the 
>signature_algorithm should in fact be relaxed.

This despite the fact that every single person who responded considered it a 
really bad idea (and some were far more vigorous in their comments than just 
"bad idea"), and that no implementation actually checks it?  This sort of
approach sounds more like PKIX than TLS.

>3. The ECC issues you raise are not issues in 5246 at all, since ECC is 
>specified in a different document (4492).

5246 claims to be an update to 4492 (line 4 of the doc), and a far more 
drastic one than just adding a few new cipher suites since it's not 
backwards-compatible with 4492.  This would be just another update of 4492,
and one that's fully backwards-compatible.

Peter.

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