Firewall Adalah sistem keamanan jaringan
komputer yang
digunakan untuk melindungi komputer dari beberapa jenis serangan dari komputer
luar.
A.Firewall ini
Ditujukan Untuk Firewall Debian 6
iptables -F
iptables -X
iptables -t filter -F
iptables -t filter -X
iptables -t filter -P INPUT DROP
iptables -t filter -P FORWARD
DROP
iptables -t filter -P OUTPUT
ACCEPT
iptables -t nat -X
iptables -t nat -F
iptables -t nat -P POSTROUTING
ACCEPT
iptables -t nat -P PREROUTING
ACCEPT
iptables -t nat -P OUTPUT ACCEPT
iptables -t mangle -F
iptables -t mangle -X
iptables -t mangle -P PREROUTING
ACCEPT
iptables -t mangle -P OUTPUT
ACCEPT
iptables -t mangle -P POSTROUTING
ACCEPT > /dev/null 2>&1
iptables -t mangle -P FORWARD
ACCEPT > /dev/null 2>&1
iptables -t mangle -P INPUT
ACCEPT > /dev/null 2>&1
iptables -t filter -A INPUT -p
icmp -j ACCEPT
iptables -t filter -A FORWARD -p
icmp -j ACCEPT
iptables -t filter -A OUTPUT -p
icmp -j ACCEPT
iptables -t filter -A OUTPUT -p
icmp -m state --state INVALID -j DROP
iptables -t nat -A POSTROUTING -s
172.16.15.0/28 -o eth0 -j MASQUERADE
iptables -t nat -A PREROUTING -p
tcp --dport 80 -s 172.16.15.0/28 -j DNAT --to-destination 192.168.15.1:3128
iptables -t filter -A INPUT -p
udp -m multiport --ports 21,23,53,123,2049,1723,111 -j ACCEPT
iptables -t filter -A INPUT -p
tcp -m multiport --ports 21,22,25,53,143,443,1723,67:69,3128,2049,111 -j ACCEPT
iptables -t filter -A INPUT -p
udp -m multiport --ports 137,138 -j ACCEPT
iptables -t filter -A FORWARD -p
udp -m multiport --ports 137,138 -j ACCEPT
iptables -t filter -A INPUT -p
tcp -m multiport --ports 139,445 -j ACCEPT
iptables -t filter -A FORWARD -p
tcp -m multiport --ports 139,445 -j ACCEPT
iptables -t filter -A INPUT -m
state --state ESTABLISHED,RELATED -j ACCEPT
iptables -t filter -A FORWARD -m
state --state ESTABLISHED,RELATED -j ACCEPT
iptables -t filter -A INPUT -m
state --state NEW -d 172.16.15.0/28 -j ACCEPT
iptables -t filter -A FORWARD -m
state --state NEW -d 172.16.15.0/28 -j ACCEPT
iptables -t filter -A INPUT -m
state --state NEW -d 192.168.15.0/29 -j ACCEPT
iptables -t filter -A FORWARD -m
state --state NEW -d 192.168.15.0/29 -j ACCEPT
echo "30" >
/proc/sys/net/ipv4/tcp_fin_timeout
echo "1800" >
/proc/sys/net/ipv4/tcp_keepalive_time
echo "1" >
/proc/sys/net/ipv4/tcp_window_scaling
echo "0" >
/proc/sys/net/ipv4/tcp_sack
echo "1280" >
/proc/sys/net/ipv4/tcp_max_syn_backlog
