> From: [email protected]  On Behalf Of Kurt Roeckx via RT
> Sent: Monday, January 13, 2014 13:35

> On Mon, Jan 13, 2014 at 05:25:55PM +0100, Jeff Hodges via RT wrote:
> > We've been testing clients using OpenSSL against
> > https://howsmyssl.com/a/check and noticed that those using
> > the OpenSSL_add_all_algorithms() have insecure export cipher suites

Aside: add_all_algorithms shouldn't affect suites offered or accepted. 
add_ssl_algorithms aka SSL_library_init provides all suite primitives, 
although in old versions (IIRC 0.9.8) it may not enable SHA-2 *certs* 
and some *PBEs* that might be needed for the privatekey file(s).

> > included by default. These cipher suites are using keys less than the
> > currently recommended 128-bit keys.
> >
By whom? NIST 800-57 only demands 112-bit strength through 2030.
That allows "3DES" (TDEA) as below. (Note we want strength not size.
For *most* symmetric ciphers key size equals strength, but not for TDEA 
as you note below, and for asymmetric and hash not even close.)

> > For instance, curl was burned by this:
> > http://sourceforge.net/p/curl/bugs/1323/
<snip>
> <snip> One major problem is that you don't always have control over the
> other side you're talking to.  <snip>

> I think we all want to have as goal that we want to have at least
> 128 bit over the whole chain.  The question is what you use as
> default and when you drop some things.
> 
Or 112. If you believe NIST, they rated 128 strength to require 
RSA, DSA or DH at 3072 which I see almost no one doing, 
though RSA *2048* is now finally widespread and rated 112. 
(For ECC it seems people are using P-256, which is 128.) Either 
112 or 128 nominally requires SHA-2 certs, which still seem rare. 
In the abstract they also require SHA-2 HMAC and thus TLSv1.2,
but HMAC is realtime only so that's much less vital.

> According to the manpage, "DEFAULT" currently stands for
> "ALL:!aNULL:!eNULL".  Maybe that should get changed to
> "ALL:!aNULL:!eNULL:!LOW:!EXPORT", dropping anything that
> uses 64 bit or less.  You'll end up with 3DES which hass 156
> bits but really only provides 112 bit, and RC4 which you might
> also want to disable.  Then there are still SEED and IDEA,
> which you also might want to disable.
> 
Actually since 1.0.0 it's ALL:!aNULL:!eNULL:!SSLv2 . But that 
effectively removes only RC2-128 (!) and some (not all!) 
HMAC=MD5 which we don't want at all. The significance 
is that it causes client Hello to use v3&TLS format which can 
have extensions, instead of v2-compatible which does not.

> Basicly you only want AES and Camellia, but you'll need
> 3DES or RC4 to be able to talk to some people.
> 
Yes.




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