[cobalt-users] sendmail rule to block relay for certain email addresses

["Kevin D" <kdlists@xxxxxxxxxxxxxxx>]

I provide email services to my Dialup customers using the SMTP of my Raq.
This of course requires me to do open relay for my block of dialup IPs.

Lately, there have been a few computer viruses that send from a specific
email address (ie hahaha@xxxxxxxxxxx), and I would like to add a rule that
would block relaying for this email address. Adding it to the "Reject the
following Users/Hosts/Domains" only prevents the server from receiving the
email, but it won't block relaying of the email from trusted IPs. Is it
possible to do selective relaying like this with sendmail 8.9.x? I have
searched the sendmail.org docs, but they are somewhat difficult to
understand.

I would also like to filter any incoming email with attachments that end in
.vbs.

Thanks,
Kevin