Re: HELO vs. MAIL FROM

Gordon Fecyk - Home wrote:
> 
> > I'm still thinking about the proposal to verify
> > the host name given in HELO/EHLO instead of
> > MAIL FROM sender envelope address.
> >
> > I agree on two details:
> >
> > - It is a good idea to consider the sending MTA as
> >   an originator of an error message if the sender
> >   envelope address is empty (<>) and to use the
> >   given host name (or it's domain part?) instead for the
> >   RMX lookup.
> 
> I think we've agreed on that a long time ago.  DMP and SPF use HELO for null
> reverse path messages.
> 
> > - It does not break any forwarding mechanism.
> 
> > I'll give a real world example:
> >
> > This particular message is sent with a sender envelope
> > address  <[email protected]>, because I am the originator
> > and initiator of the message. correct.
> >
> > But it is delivered to the world through my ISP's relay
> > which's host name is sklave3.rackland.de, which is also
> > used in the EHLO command.
> 
> Hm, I wonder if some kind of provision could be made such that, if checking
> MAIL FROM fails, at least ensure the HELO'd hostname is valid so we know who
> is responsible for sending the mail.  I'm interested in restoring
> accountability, but it actually doesn't matter who I restore accountability
> TO.

There can be multiple accountabilities: the SMTP MAIL FROM accountability, and
the SMTP HELO accountability.


Raymond S Brand