On Wed, 12 Jan 2000, Wilf wrote:
> I'd like to check for NULL sender in 'MAIL FROM:' but only from hosts
> outside our local domain (to stop outgoing list messages that came in
> with NULL sender from being rejected further down the line by other
> remote MTAs).
I'm not sure what you mean by "check for", but if you mean "reject", you
will come to grief because bounce messages are defined to have null
envelope senders.
> With headers_sender_verify_errmsg set, all SMTP connections are checked
> regardless of the setting of sender_verify_hosts.
headers_sender_verify_errmsg checks *header* lines, but only if the
envelope sender is null. This isn't the same thing as checking the MAIL
FROM command.
sender_verify_hosts controls the checking of the MAIL FROM command, but
null senders are always accepted. They have to be. The RFCs say so.
> local -> MTA : initiates SMTP session for an unknown user
Why is the user unknown? If "local" is running Exim, it should set up
the sender from the login id of the process that called it. I think you
should tackle the problem at this level.
> Should the setting of sender_verify_hosts affect the operation of
> headers_sender_verify_errmsg? If not, is there a way around this?
I don't believe it should.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
