FreeBSD Security Advisory FreeBSD-SA-09:15.ssl

[Maxim Dounin]

Hello!

On Thu, Dec 10, 2009 at 11:46:32AM -0800, Chris Palmer wrote:

> Maxim Dounin writes:
> 
> > It's not true.  Patch (as well as OpenSSL 0.9.8l) breaks only apps that do
> > not request client certs in initial handshake, but instead do it via
> > renegotiation.  It's not really commonly used feature.
> 
> The ideal case is not the typical case:
> 
> http://extendedsubset.com/Renegotiating_TLS_pd.pdf
> 
> The plain fact is that client cert auth often needs reneg in apps as
> deployed in the world. Often, web servers need to check (for example) a
> virtual-host-specific configuration before realizing they need to request
> client cert auth.

While talking about "often" - do you have any stats?  Anyway, this 
is quite a differenet from "all client cert-powered apps" you 
stated in your previous message.

I'm not trying to say this patch doesn't break anything.  It does, 
and most common case is probably Apache with per-location client 
cert configs.  But:

- it's not all apps with client certs which are broken, just a 
  [relatively small as far as I know] share of them;

- not patching is not an option as it leaves unsecure much more 
  installations.

Maxim Dounin