On Thu, 2009-11-12 at 18:07 -0500, Adam Katz wrote: > Neroxyr may have been asking something else. Is this regarding mail > *received* from unknown senders? Do you want to check for forged > senders? Do you want to check for invalid recipients? > > Forgery can be mitigated with SPF* and/or DKIM while invalid > recipients has no easy solution. A plugin could conceivably check > against a passwd file (and aliases, virutal users, ...) to catch for > invalid users at the local domain(s) that appear in the message > headers, but I don't know of such a thing. > Do we know the OIP is using sendmail?
Postfix checks local recipients against /etc/passwd and /etc/aliases by default. It can also be configured to apply the same checks to local senders though the defajult is not to check. I'd hope that other MTAs have the same capabilities. Martin
