> [[email protected] - Sun Mar 25 04:51:32 2012]:
> 
> On Fri, Mar 23, 2012 at 06:49:43PM +0100, Stephen Henson via RT wrote:
> > > [[email protected] - Fri Mar 23 18:21:39 2012]:
> > >
> > > OpenSSL negotiation times out when connecting to Outlook Exchange
> 2007
> > > both through Outlook Web Access (webmail) and IMAP (POP untested).
> This
> > > bug appeared between version 1.0.0h and 1.0.1-beta1.
> > >
> > > OS: Arch Linux
> > > Applications tested: Offlineimap (IMAP), elinks (webmail), wget
> (webmail).
> > > Version: 1.0.1, 1.0.1-beta{3,2,1}.
> > > Versions-not-affected: 1.0.0h
> > >
> > > To reproduce, run `wget https://owa.mit.edu/`.
> > >
> >
> > It isn't clear that this is a problem with OpenSSL. The server
> doesn't
> > seem to be responding to the OpenSSL client hello. If you disable
> > TLSv1.2 (with -no_tls1_2) or disable AES or ECDH ciphersuites or
> various
> > other things it responds OK.
> 
> -no_tls1_2 and -no_tls1_1 doesn't work for me, I need to use -tls1
> (or -ssl3) to be able to get a connection.
> 
> gnutls-cli which also supports TLS 1.1 and 1.2 works with that
> site without problem.
> 
> https://sourceforge.net/ has the same problem, both report BigIP
> as the server.
> 

Disabling TLSv1.2 will eliminate some ciphersuites and the signature
algorithm extension. Due to a bug it still sends that extension in
OpenSSL 1.0.1 if you specify -no_tls1_2. This fixes it:

http://cvs.openssl.org/chngview?cn=22286

It should then also work with -no_tls1_2. Without that option some
arguments also allow a connection. For example -cipher 'DEFAULT:!ECDH'
or -cipher 'DEFAULT:!AES'.

I've done some more tests and it seems that the size of the client hello
message is significant: all the options that work reduce the size of
client hello. If you use the -debug option and check out the first
message bytes 4 and 5 it seems those servers hang if the length exceeds
0xFF (using two bytes instead of one).

Steve.
-- 
Dr Stephen N. Henson. OpenSSL project core developer.
Commercial tech support now available see: http://www.openssl.org

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