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Re: [TLS] Deprecate SHA1 for signatures in TLS 1.3 (was Re: TLS 1.3 draft-07 sneak peek)

mrex@sap.com (Martin Rex) Mon, 13 July 2015 16:10 UTC

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To: Dave Garrett <davemgarrett@gmail.com>
Date: Mon, 13 Jul 2015 18:10:52 +0200
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Subject: Re: [TLS] Deprecate SHA1 for signatures in TLS 1.3 (was Re: TLS 1.3 draft-07 sneak peek)
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Dave Garrett wrote:
> On Monday, July 13, 2015 10:30:06 am Martin Rex wrote:
>> Section 7.4.1.4 Hello Extensions and its subsections are clearly
>> IRRELEVANT for a client that does not use Hello Extensions.
> 
> If you want to put it that way, sure, however they are NOT irrelevant
> for a _server_ that does use hello extensions. This is a direct part
> of the TLS 1.2 spec,

That particular MUST in 7.4.1.4.1 is *VOID* because it is incompatible with
rfc2119 section 6.  As it can be easily verified, the behaviour
described in rfc5246 is detrimental to interoperability and security.


-Martin

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