Re: [TLS] One approach to rollback protection

Eric Rescorla <ekr@rtfm.com> Tue, 27 September 2011 00:33 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 26 Sep 2011 17:35:57 -0700
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To: mrex@sap.com
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Subject: Re: [TLS] One approach to rollback protection
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On Mon, Sep 26, 2011 at 5:33 PM, Martin Rex <mrex@sap.com>; wrote:
> Eric Rescorla wrote:
>>
>> P.S. Yes, I know this is a big stinking hack.
>
> We've been seeing a significant delay in adoption of TLSv1.1.
> So while it might smell like a dirty hack to some, I think it is a
> reasonable approach to ease the transition pain for the installed base.
>
> As it turned out, the TLS cipher suites were the only protocol extensibility
> that had been really interop tested from the beginning, probably because the
> list of cipher suites was already quite long when Netscape brought
> SSLv3 to the IETF for standardization and most new implementors
> started interop testing with much fewer cipher suites in their
> initial implementations.
>
> If you look at slowly IPv6 adoption is progressing, it looks like they
> do not have enough "dirty hacks" in place yet.  :-]

I tend to agree with you here... I was just
trying to preempt people telling me that using the cipher suites was ugly,
since I wholly agree with that criticism. I just figure it's ugly but necessary.

Best,
-Ekr