Re: smtp authentication (sendmail relay)

[Harry Putnam <reader@newsguy.com>]

Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Gro_johann) writes:
> On Sun, 17 Dec 2000, Harry Putnam wrote:
> 
> > I have a second smtp.server that I can use.  The smtp side of
> > newsguy.com.  I use that pop server routinely.  But suddenly find
> > I
> > don't know how to authenticate my relay to an smtp.server that is
> > not part of the isp I'm dialed up with.  I know how to set
> > /etc/sendmail.cf to relay to that server but not how to
> > authenticate
> > my outgoing relay to that machine.
> 
> I don't know that ISP, but it is possible for them to use your IP
> address for authentication.  To get the right IP address, you have
> to
> use their server for dialin, of course.

Hoping it won't be considered too off-topic to discuss the nitty
gritty details of mail sending and retrieval here:

First let me say, that it appears the easiest temporary way may be to
just let gnus do the pop and smtp transactions.  I haven't actually
done that before but it is fairly well documented here and on
gnu.emacs.gnus. So shouldn't have too much trouble with that.

However as is ofter the case, I'm looking for a more optimal solution,
that could be used by simply overwriting sendmail.cf and restarting
sendmail.

Let me explain my situation a little better, making use of the nifty 
`picture mode' and listing the tools involved:

                My machine .. running local sendmail for send and 
                fetchmail/sendmail/procmail  for retrieval.
                             _______ 
                             |      |
                             | Me   |
                             |______| 
                             /      \  
                            /        \  
                           /          \
                          /            \
                      ISP|ISPsmtp    Newsguy|POP3
                                                
So.. I connect to a local ISP, use there SMTP server to relay my
outgoing
mail via my local sendmail.  No special authentication is required,
apparently done transparently, from the ISP authentication (login).
 (sendmail.cf set to this smtp.server as the machine to relay to)

(That is temporarily broken)

I collect mail from newsguys' POP3 server using fetchmail, in the
simplest
possible format, which includes authentication:

cat .fetchmailrc
poll pop.newsguy.com proto pop3 nodns user reader password xxxxxxxx
Fetchmail drops it in /var/spool/mail where gnus snarfs it.

To direct sendmail to deliver to a different smpt server, is no harder
than
editing the single line in sendmail.cf:

DSsmtp:smtp.MYLOCAL.ISP
                        
to read
                                                
DSsmtp:smtp.newsguy.com

And restarting sendmail.

But when doing this, the connection is rejected by newsguy since no
authentication is provided.  The hub of my question is how to provide
that
authentication and not have to make other changes in my current setup.

I want to be able to simply overwrite sendmail, restart it and....
bingo.  Now relying thru server smtp.XXX.XXX

One would expect that Newsguy.com would have this kind of info readily
available but apparently there techs only deal with `windows' clients.

 > 
 > Another common scheme is smtp-after-pop.  Here, the idea is that
 > you
 > connect to the POP server, and if that's successful, then for 5
 > minutes (or whatever) you're (your IP address is) allowed to use
 > the
 > SMTP server.

This sounds like a possible option...

 > 
 > I think there are also schemes for doing authentication within
 > SMTP,
 > but I think they are rarely used.  They are also non-standard, I
 > think. 

Is this last `within' scheme what I am describing above?


 jas@slipsten.extundo.com writes:

 > On Sun, 17 Dec 2000, Harry Putnam wrote:
 > 
 > > I have a second smtp.server that I can use.  The smtp side of
 > > newsguy.com.

[...]

 > 
 > Perhaps you could use modern smtpmail.el which support SMTP
 > authentication (RFC 2554), rather than a local sendmail?  If so,
 > customize
 > the `smtpmail' group.

Another posssible way .. thanks.

 > 
 > Hopefully Emacs will contain smtpmail.el with AUTH support in the
 > future.  XEmacs mail-lib in CVS contains it now.

 "Robin S. Socha" <robin@socha.net> writes:

 > * Harry Putnam <reader@newsguy.com> writes:
 > 
 > > Finding myself in an unusaual temporary situation where for
 > > technical
 > > reasons I cannot relay my outgoing mail through my normal ISP
 > > smtp
 > > machine.
 > 
 > You are now reader@socha.net, PWD R34d3r
 > To login, use reader@socha.net, to relay over this machine, get
 > POP3
 > first (smtp after pop). https://socha.net:666/webmail/ is also
 > there,
 > altough the account settings are slightly broken ;-)

Thanks Robin.. same as above solution `smtp after pop'.

Due to your characteristic breivity... Its not clear if there would be
a way to do what I've described above on that smtp server.  Please set
-v to the next higher level....  : )