Hi Joe,

this sound quite reasonable, especially the "dedicated port" argument is
a good one. And, of course, if the -transport-tls connection fails, a
local syslog sender may still be configured to fall back to some other
mode (e.g RFC 3195 or RFC 3164). It just isn't then using
-transport-tls.

However, I think this "MUST fail" should be explicitly spelled out in
the draft. Otherwise we have some confusion. The issue arose from this
conversation with Martin:

http://mail-index.netbsd.org/tech-userlevel/2008/05/06/msg000553.html

I remember similar discussions when implementing RFC 3195 and they lead
to interop problems between different implementations (namely SDSC
syslogd vs. liblogging vs. Cisco IOS). In that case, there was a
somewhat unclear definition about the session closure (which stems back
to RFC 3080 and is not a 3195 issue).  Would like to prevent this for
-transport-tls if at all possible. OF course, we won't catch anything,
but now that we begin implement (and still have a draft and not a final
RFC), we should feedback experience into the draft. At least this is my
humble POV.

Rainer

> -----Original Message-----
> From: Joseph Salowey (jsalowey) [mailto:[EMAIL PROTECTED]
> Sent: Tuesday, May 06, 2008 11:56 PM
> To: Rainer Gerhards; [email protected]
> Subject: RE: [Syslog] -transport-tls, section 4.2
> 
> Since Syslog TLS is taking the approach of a separate TCP port for TLS
> I
> think it would be more appropriate to reject the connection instead of
> falling back to insecure.  I am inclined to say that if the handshake
> fails the connection MUST be terminated.   If the client wants an
> insecure session they can connect to the insecure port.
> 
> Joe
> 
> > -----Original Message-----
> > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED] On Behalf Of Rainer Gerhards
> > Sent: Tuesday, May 06, 2008 5:38 AM
> > To: [email protected]
> > Subject: [Syslog] -transport-tls, section 4.2
> >
> > Hi there,
> >
> > I have today released a basic version of rsyslog with an
> > experimental first -transport-tls implementation
> > (announcement at http://www.rsyslog.com/Article222.phtml ). I
> > am now digging deeper and refining the implementation. I try
> > to convey some thoughts and ask some questions along this
> > route - in the hopes to gather some feedback.
> >
> > The initial feedback is that it is quite trivial to implement
> > -transport-tls - just as anticipated. But I think it is good
> > to see it works out in practice.
> >
> > My first question is on section 4.2. It does not tell what to
> > do if the TLS handshake fails. One can argue that the second
> > sentence implies that the connection should be dropped on
> > handshake failure. However, this is not explicitly stated. It
> > may be desirable to continue without TLS in that case.
> >
> > When GSSAPI support was implemented in rsyslog, there was a
> > strong community demand for such a fallback mode. Thus, if
> > the GSSAPI handshake fails, and rsyslog is configured
> > accordingly, it falls back to plain TCP syslog (unencrypted).
> > I know this is dangerous, as a man in the middle may force
> > unencrypted transfer in this case. But provided it is an
> > operator-selectable option (and by default off), I think it
> > is an acceptable risk.
> >
> > Question now: how to handle this in spite of -transport-tls?
> > With the current text, would my application compliant to it
> > if it permits to run without TLS support when the handshake
> > fails (in that case obviously not complying to any standard)?
> >
> > I would suggest that this case is being at least mentioned. I
> > would also like to hear some opinions on this topic.
> >
> > Thanks,
> > Rainer
> > _______________________________________________
> > Syslog mailing list
> > [email protected]
> > https://www.ietf.org/mailman/listinfo/syslog
> >
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