Re: [TLS] WGLC: draft-ietf-tls-prohibiting-rc4-00

[Hubert Kario <[e-mail]>]

----- Original Message -----
> From: "Martin Rex" <[e-mail]>
> To: "Hubert Kario" <[e-mail]>
> Cc: [e-mail], "Sean Turner" <[e-mail]>, "[e-mail] ([e-mail])" <[e-mail]>
> Sent: Friday, 8 August, 2014 4:56:58 PM
> Subject: Re: [TLS] WGLC: draft-ietf-tls-prohibiting-rc4-00
> 
> Hubert Kario wrote:
> > 
> >> There currently exists *no* known attack against the integrity
> >> protection of the TLS handshake, so this looks primarily like an
> >> attempt to promote "planned obsolesence", and a poor excuse for
> >> Microsoft to actively break interop with Windows XP (and potentially
> >> other installed base).
> > 
> > 3DES remains an option if you need to interoperate with very old
> > systems. It doesn't break interoperability with Windows XP.
> > 
> >  0 - http://blog.cloudflare.com/killing-rc4-the-long-goodbye
> 
> 
> This is the theory.
> In theory, theory an practice are the same, in practice they differ.
> 
> There seems to be stuff that breaks with TLS cipher suites that
> use padding.  This is just Windows stuff, I've also seen such
> interop problems with Java (J2SE) client (using nio it seems),
> that will simply not interop with 3DES-EDE (nor AES128-SHA),
> and RC4 is the only alternative that works.

Those are bugs, if you _need_ to work around them, then work around them,
that's what MUST means.

But don't deploy those workarounds unless you're:
 1). sure that they are needed
 2). sure that this is the only way to workaround the issue

-- 
Regards,
Hubert Kario