From: Amnon Cohen <[EMAIL PROTECTED]>

There are very few (if at all?) browsers that do TLS1 by default, as
far as I remember.

This can be shown with s_client this way (Oscar, s_client does SSLv23
by default, just so you know :-)):

   openssl s_client  -connect commerce.www.ibm.com:443 -no_tls1

Also, adding the flags '-state' and '-debug' gives you more output on
what's really happening.

amnonc> How do browsers manage to connect to these defective servers?
amnonc> 
amnonc> Is there any way we can make OpenSSL emulate browser behaviour?
amnonc> 
amnonc> Thanks
amnonc>         Amnon
amnonc> 
amnonc> -----Original Message-----
amnonc> From: Oscar Jacobsson [mailto:[EMAIL PROTECTED]]
amnonc> Sent: Wednesday, October 10, 2001 7:42 PM
amnonc> To: [EMAIL PROTECTED]
amnonc> Cc: Amnon Cohen
amnonc> Subject: Re: SSL3_GET_RECORD:bad mac decode on SSLv23
amnonc> 
amnonc> 
amnonc> Hi!
amnonc> 
amnonc> I *think* the problem you are describing is actually on the server side.
amnonc> 
amnonc> IIRC this is because your s_client by default will attempt to use TLS
amnonc> 1.0 (SSL 3.1), which the server incorrectly parses as SSL 3.0 (ignoring
amnonc> the minor version number).
amnonc> 
amnonc> TLS 1, which s_client assumes both parties have agreed to use, uses a
amnonc> different message authentication strategy than SSL 3.0, which is what
amnonc> the server thinks has been agreed.
amnonc> 
amnonc> Thus, the server ends up generating a MAC which s_client is not able to
amnonc> verify, thus the error.
amnonc> 
amnonc> If you explicitly tell s_client to only use SSL 2 or 3 this problem gets
amnonc> worked around.
amnonc> 
amnonc> I'd better apologize in advance in case I've got this wrong. :-)
amnonc> 
amnonc> //oscar
amnonc> 
amnonc> Amnon Cohen wrote:
amnonc> > 
amnonc> > Hi,
amnonc> > 
amnonc> > I am having trouble performing a SSLv23 handshake to a large number of
amnonc> > servers
amnonc> > e.g.
amnonc> > 
amnonc> > OpenSSL> s_client  -connect commerce.www.ibm.com:443
amnonc> > Loading 'screen' into random state - done
amnonc> > CONNECTED(00000028)
amnonc> > 497:error:1408F071:SSL routines:SSL3_GET_RECORD:bad mac
amnonc> > decode:.\ssl\s3_pkt.c:383:
amnonc> > 
amnonc> > with -ssl3 or ssl2, the connect succeeds.
amnonc> > 
amnonc> > I have searched the archives and found this problem mentioned a number of
amnonc> > times,
amnonc> > but no explanation or solution.
amnonc> > 
amnonc> > Is this a bug in the openssl client or in IBM's server.
amnonc> > If it is a bug in openssl, is a fix planned?
amnonc> > 
amnonc> > If it is a bug in IBM's server, is there an argument to SSL_set_options()
amnonc> > which will work around this bug?
amnonc> > 
amnonc> > Many Thanks!
amnonc> >     Amnon Cohen
amnonc> > ______________________________________________________________________
amnonc> > OpenSSL Project                                 http://www.openssl.org
amnonc> > Development Mailing List                       [EMAIL PROTECTED]
amnonc> > Automated List Manager                           [EMAIL PROTECTED]
amnonc> ______________________________________________________________________
amnonc> OpenSSL Project                                 http://www.openssl.org
amnonc> Development Mailing List                       [EMAIL PROTECTED]
amnonc> Automated List Manager                           [EMAIL PROTECTED]
______________________________________________________________________
OpenSSL Project                                 http://www.openssl.org
Development Mailing List                       [EMAIL PROTECTED]
Automated List Manager                           [EMAIL PROTECTED]

Reply via email to