On Tue, Jun 12, 2012 at 3:04 PM, Garrison, Jim (ETW) <[email protected]> wrote: >> -----Original Message----- >> From: [email protected] [mailto:owner-openssl- >> [email protected]] On Behalf Of Garrison, Jim (ETW) >> Sent: Tuesday, June 12, 2012 10:41 AM >> To: [email protected] >> Subject: RE: Configure OpenSSL to skip SSL1 & SSL2? >> >> > -----Original Message----- >> > From: [email protected] [mailto:owner-openssl- >> > [email protected]] On Behalf Of Jeffrey Walton >> > Sent: Monday, June 11, 2012 8:38 PM >> > To: [email protected] >> > Subject: Re: Configure OpenSSL to skip SSL1 & SSL2? >> > >> > On Mon, Jun 11, 2012 at 4:32 PM, Garrison, Jim (ETW) >> > <[email protected]> wrote: >> > > I am trying to connect to a subversion server that requires https, >> > > and for some reason, is configured to require SSL3 or TLS1. It >> > > refuses to respond to SSL or SSL2. >> > You are lucky its responds to SSLv3. I would shut it down too (TLSv1 >> > is not too far away for me, either). >> >> So, the question remains. Is this something that can be configured at >> runtime? >> >> Also, If the server disallows certain protocols, shouldn't its SSL >> implementation >> respond with a negotiation sequence when the client attempts to use a >> disallowed protocol? Is the total lack of response to an SSL1 CLIENT HELLO >> surprising, or is that the expected behavior? The server is Apache. >> >> > >> > > I’ve done some troubleshooting using s_client and confirmed that if >> > > I let s_client start with the default protocol the server never >> > > responds to the CLIENT HELLO: >> > > >> > > $ openssl s_client -connect server.domain.com:443 >> > > CONNECTED(00000003) >> > > write:errno=104 >> > > --- >> > > no peer certificate available >> > > --- >> > > No client certificate CA names sent >> > > --- >> > > SSL handshake has read 0 bytes and written 320 bytes >> > > --- >> > > New, (NONE), Cipher is (NONE) >> > > Secure Renegotiation IS NOT supported >> > > Compression: NONE >> > > Expansion: NONE >> > > --- >> > > Watching this in Wireshark I see: >> > > Client Server >> > > -------syn----------> >> > > <------ack----------- >> > > --SSL CLIENT HELLO--> >> > > <------ack----------- >> > > [60 second pause] >> > > <------rst----------- > > After more research I have discovered that the problem is not an old > protocol, but maybe a too-new protocol. Here are the two cases: > > * openssl s_client -connect gbit:443 > > This sends a TLSv1.2 handshake inside a TLSv1.0 CLIENT HELLO, and Apache > fails to respond. > > * openssl s_client -connect gbit:443 -tls1 > > This sends a TLSV1.0 handshake inside a TLSV1.0 CLIENT HELLO. Apache accepts > the connection > > Is this expected behavior? AFAICT Apache does not have a config option to > explicitly enable TLSv1.2 negotiation. http://httpd.apache.org/docs/trunk/mod/mod_ssl.html. Be mindful of secure renegotiations, also.
Jeff ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List [email protected] Automated List Manager [email protected]
