Chris Johnson <[EMAIL PROTECTED]> writes:
| On Fri, Feb 19, 1999 at 12:45:06PM -0500, Scott Schwartz wrote:
| > The question arises, however, why those aol users don't just submit their
| > mail to aol's smtp server? Presumably an aol user, just like any person on
| > the internet, can submit a message to their local smtp server (for which they
| > are authenticated) with a "From:" line that has one of your virtual domains
| > in it (or indeed, any string they like). So why do aol users need to use you
| > as their injection point?
|
| Try this with msn.com. If you're connected to their network and submit a
| message to the local smtp server using a "From" address that isn't an msn.com
| address, they'll *silently* discard your mail. They'll accept it, and without
| warning deposit it into a bitbucket. (This was the case several months ago.
| They may have wised up since, but I doubt it.) I've heard that other ISPs are
| requiring that the envelope sender domain be one of their domains in order for
| you to be able to relay, thus making them unusable as relays if you use a
| different address. At one point (and this may have changed), ibm.net would give
| you a "550: Unauthorized access" as soon as it saw a MAIL FROM with a
| non-ibm.net address.
Are you talking about envelope sender or From line? They don't need to
be the same at all. For most purposes, getting the From line right
should satisfy your virtual domain users.
| I don't recommend that anyone run an open relay and I'll continue to tell
| people not to and to refer them to FAQ 5.4, but I'm becoming increasingly
| sympathetic to people who think they need to. Whether the problem can be fixed
| without some kind of username/password authentication in SMTP I don't know, but
| I think it's something worth talking about.
Probably the easiest solution is an applet on the PC that tunnels
127.0.0.1:25 to a private smtp or qmtp server on the mail host, doing
authentication in the process. SMOP. Wasn't there a usenix paper about
this a while back?
