Salut, Stanislav,
On Mon, 19 Oct 2009 12:30:09 -0700 (PDT), Stanislav Sinyagin wrote:
Martin implemented this hack in a FreeBSD kernel module. Of course this gives more room for performance, but then it binds the solution to a specific OS and kernel release. I personally feel there's something wrong if the kernel has to deal with an application-level protocol. On the other side, you usually install a dedicated server just for incoming mail processing.
It's fairly easy to implement in Postfix:
smtpd_helo_restrictions = reject_invalid_helo_hostname, reject_non_fqdn_helo_hostname, permit_mynetworks, check_helo_access hash:/usr/pkg/etc/postfix/checks/helo_checks, sleep 30, reject_unauth_pipelining, permit
There you go.