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I want to prevent my server from port scanning from Internet. And if port scanning occurs, block source IP address for several minutes
Below mu current iptables config:
Code:
Lilith> iptables --list-rules
-P INPUT ACCEPT
-P FORWARD ACCEPT
-P OUTPUT ACCEPT
-N DOS_PROTECT
-A INPUT -i eth1 -j DOS_PROTECT
-A INPUT -i eth0 -j DOS_PROTECT
-A INPUT -i lo -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -i eth0 -p tcp -m tcp --dport 80 -j DROP
-A INPUT -i eth0 -p udp -m udp --dport 80 -j DROP
-A INPUT -i eth0 -p tcp -m tcp --dport 587 -j DROP
-A INPUT -i eth0 -p udp -m udp --dport 587 -j DROP
-A INPUT -i eth0 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 666 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 667 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 5006 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 993 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 587 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 465 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 8443 -j ACCEPT
-A INPUT -i eth1 -j DROP
-A DOS_PROTECT -i eth1 -p icmp -m icmp --icmp-type 8 -m limit --limit 1/sec -j RETURN
-A DOS_PROTECT -i eth1 -p icmp -m icmp --icmp-type 8 -j DROP
-A DOS_PROTECT -i eth1 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK RST -m limit --limit 1/sec -j RETURN
-A DOS_PROTECT -i eth1 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK RST -j DROP
-A DOS_PROTECT -i eth1 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -m limit --limit 10000/sec --limit-burst 100 -j RETURN
-A DOS_PROTECT -i eth1 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -j DROP
-A DOS_PROTECT -i eth0 -p icmp -m icmp --icmp-type 8 -m limit --limit 1/sec -j RETURN
-A DOS_PROTECT -i eth0 -p icmp -m icmp --icmp-type 8 -j DROP
-A DOS_PROTECT -i eth0 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK RST -m limit --limit 1/sec -j RETURN
-A DOS_PROTECT -i eth0 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK RST -j DROP
-A DOS_PROTECT -i eth0 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -m limit --limit 10000/sec --limit-burst 100 -j RETURN
-A DOS_PROTECT -i eth0 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -j DROP
Lilith> iptables --list
Chain INPUT (policy ACCEPT)
target prot opt source destination
DOS_PROTECT all -- anywhere anywhere
DOS_PROTECT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
DROP tcp -- anywhere anywhere tcp dpt:http
DROP udp -- anywhere anywhere udp dpt:http
DROP tcp -- anywhere anywhere tcp dpt:submission
DROP udp -- anywhere anywhere udp dpt:submission
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere tcp dpt:666
ACCEPT tcp -- anywhere anywhere tcp dpt:667
ACCEPT tcp -- anywhere anywhere tcp dpt:5006
ACCEPT tcp -- anywhere anywhere tcp dpt:imaps
ACCEPT tcp -- anywhere anywhere tcp dpt:submission
ACCEPT tcp -- anywhere anywhere tcp dpt:urd
ACCEPT tcp -- anywhere anywhere tcp dpt:8443
DROP all -- anywhere anywhere
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOS_PROTECT (2 references)
target prot opt source destination
RETURN icmp -- anywhere anywhere icmp echo-request limit: avg 1/sec burst 5
DROP icmp -- anywhere anywhere icmp echo-request
RETURN tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/RST limit: avg 1/sec burst 5
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/RST
RETURN tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/SYN limit: avg 10000/sec burst 100
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/SYN
RETURN icmp -- anywhere anywhere icmp echo-request limit: avg 1/sec burst 5
DROP icmp -- anywhere anywhere icmp echo-request
RETURN tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/RST limit: avg 1/sec burst 5
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/RST
RETURN tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/SYN limit: avg 10000/sec burst 100
DROP tcp -- anywhere anywhere tcp flags:FIN,SYN,RST,ACK/SYN
Lilith>
I want to insert for interface eth1 anti-scanning rule. How can I do it?
I try:
Code:
iptables -A INPUT -m recent –name portscan –rcheck –seconds 900 -j DROP
iptables -A FORWARD -m recent –name portscan –rcheck –seconds 900 -j DROP
but error was reported:
Code:
Lilith> iptables -A INPUT -m recent –name portscan –rcheck –seconds 900 -j DROP
iptables v1.4.21: Couldn't load match `recent':No such file or directory
Yes I know this post so I try touse similar rules. But look to my post what happens:
Code:
Lilith> iptables -A INPUT -m recent –name portscan –rcheck –seconds 900 -j DROP
iptables v1.4.21: Couldn't load match `recent':No such file or directory
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