I want to dynamically block specific connections that use the same IP address based on a rate or connection limit. Is this possible using Solaris/IPF or some sendmail extension? I want to limit sendmail login attempts to prevent brute force attacks.
In Linux it's easily handled on the iptables firewall layer, but I haven't been able to figure out a way to use ipf to limit it on the firewall layer. Sendmail has a built-in rate limit and connection limit, but it appears to be applied to all users so if we're experiencing a DOS or DDOS it would block all our users instead of just the attacker.