Hack Security Pro.pdf - Index of

The rules take the following values:
INPUT Entering traffic
OUTPUT Outgoing traffic
FORWARD Will be used to carry out port forwarding
The chains take the following values:
MASQUERADE Will be used to carry out ip masquerading
ACCEPT Accept the communication
REJECT Forbid the communication and send a reject packet
DROP Forbid the communication, but do not send any packet
You can now create your own iptables configuration script. Here are a few examples. Beware, these
are only simplistic examples, and in no way efficient filtering rules. We will see more efficient
configurations in the following course.
First of all, for the policy by default to be to forbid everything:
iptables -P INPUT DROP
iptables -P OUTPUT DROP
iptables -P FORWARD DROP
To authorize communications on the local network and on the interface lo:
iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT
iptables -A INPUT -s 192.168.1.0/24 -j ACCEPT
iptables -A OUTPUT -d 192.168.1.0/24 -j ACCEPT
iptables -A FORWARD -s 192.168.1.0/24 -j ACCEPT
To authorize outgoing dns requests:
iptables -A INPUT -i ppp0 --protocol udp --source-port 53 -j ACCEPT
iptables -A OUTPUT -o ppp0 --protocol udp --destination-port 53 -j ACCEPT
iptables -A INPUT -i ppp0 --protocol tcp --source-port 53 -j ACCEPT
iptables -A OUTPUT -o ppp0 --protocol tcp --destination-port 53 -j ACCEPT
To authorize the outgoing web navigation:
iptables -A INPUT -i ppp0 --protocol tcp --source-port 80 -m state --state ESTABLISHED
iptables -A OUTPUT -o ppp0 --protocol tcp --destination-port 80 -m state --state
NEW,ESTABLISHED
The Hackademy DMP -203/209- SYSDREAM