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Re: [TLS] PR for anti-downgrade mechanism

Eric Rescorla <ekr@rtfm.com> Fri, 09 October 2015 13:17 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Fri, 09 Oct 2015 15:16:49 +0200
Message-ID: <CABcZeBP1oSGu53nF9U=CLJshDW8=ZNPHcLm5da7jzGYWti2rkg@mail.gmail.com>
To: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>
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Subject: Re: [TLS] PR for anti-downgrade mechanism
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On Fri, Oct 9, 2015 at 3:09 PM, Karthikeyan Bhargavan <
karthik.bhargavan@gmail.com> wrote:

>
> > For reference, the version field in the TLS premaster secret is not
> checked by many servers, IIRC some of them have large market shares.
>
> That’s good to know. It would be tempting to recommend that TLS 1.3
> servers disable RSA (encryption) ciphersuites for all protocol versions,
> but I guess this is not likely to happen for backwards compatibility
> reasons?


This seems like RFC 6919 Territory:
https://tools.ietf.org/html/rfc6919#section-1

-Ekr

>
> > --
> > Sincerely,
> > Yngve N. Pettersen
> >
> > _______________________________________________
> > TLS mailing list
> > TLS@ietf.org
> > https://www.ietf.org/mailman/listinfo/tls
>
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