I wan't a more secure way of relaying messages. Is it possible to do this:
roaming-users (if access pop3 sucessfully, than he can send messages from the ip he is for 180 mins)
If the sender is in the tcp.smtpd file (he can relay), than check that the from address is valid on the system. If it is not, than deny. If it is, than accept mail for relaying.
Is this idea too stupid, or not ?
This kind of solution exists ?
of course i am using qmail + vpopmail (currently installing 5.4)
The qmail-smtpd-chkusr patch checks if a user is exists on the vpopmail system, than delivers the mail locally. It will deliver the mail if the domain is using catch-all enabled ?
Is it possible to user this patch (with modifications) to do relay check ?