How to block flood !?

Hello, some days I am subjected to flood attacks, and not just me and half Counter-Strike 1.6 Servers in the world. The problem is that people who use Linux have been able to block packets.

Length:13 Съд:FF-FF-FF-FF-56 пакет: 45-08-00-21-01-5D-00-00-F9-11-41-94-4F-B3-6D-0E-C0-A8-01-69-00-50-69-78-00-0D-C1-38-FF-FF-FF-FF-56	

and →

Length:17 Съд:FF-FF-FF-FF-56-FF-FF-FF-FF пакет:45-00-00-25-AA-33-00-00-F8-11-20-8F-4D-1C-E8-D7-C0-A8-01-69-00-50-69-78-00-11-47-FE-FF-FF-FF-FF-56-FF-FF-FF-FF

and added this rule

-I INPUT -p udp -m udp -m string --hex-string "|45080021015D0000F91141944FB36D0EC0A8016900506978000DC138FFFFFFFF56|" --algo kmp -j DROP
-I INPUT -p udp -m udp -m string --hex-string "|FFFFFFFF56|" --algo kmp -j DROP

My question is how to COMODO Firewall can block people who are the windows that flood

ip table with lines are enough to block all floods