Re: 9.2.2 Cipher fallback and FF<->Jetty interop problem

On Fri, Sep 5, 2014 at 3:35 PM, Michael Sweet <msweet@apple.com> wrote:

> Martin,
>
> Responses inline...
>
> On Sep 5, 2014, at 5:44 PM, Martin Thomson <martin.thomson@gmail.com>
> wrote:
> > ...
> > I can't really do anything about that without overturning a standing
> > decision.  I'm not the chair, but I'm guessing that you'd have to
> > exhibit more than discomfort for that to happen.
>
> RFC 5246 requires a conforming implementation to be able to negotiate
> TLS_RSA_WITH_AES_128_CBC_SHA.  HTTP/2 requires conformance to RFC 5246 but
> forbids negotiation of TLS_RSA_WITH_AES_128_CBC_SHA.  Do you not see the
> problem this creates?
>

This is actually not a conformance problem, since RFC 5246 has an explicit
escape hatch for applications (https://tools.ietf.org/html/rfc5246#section-9
)

   In the absence of an application profile standard specifying
   otherwise, a TLS-compliant application MUST implement the cipher
   suite TLS_RSA_WITH_AES_128_CBC_SHA (see Appendix A.5
<https://tools.ietf.org/html/rfc5246#appendix-A.5> for the
   definition).


Note: I'm not saying that requiring AEAD is wise or unwise, but merely

that it's not a process problem for HTTP to do so.


-Ekr